137 results on '"Akihito Yamamoto"'
Search Results
2. Carcinosarcoma of the uterus, derived from subserous cystic adenomyosis, presenting as an acute abdomen: A case report and review of the literature
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Kaoru Hashizume, Masafumi Toyoshima, Tatsunori Shiraishi, Yuta Ueno, Akihito Yamamoto, Rieko Kawase, Yoshimitsu Kuwabara, Takashi Sakatani, and Shunji Suzuki
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Acute abdomen ,Carcinosarcoma ,Cystic adenomyosis ,Malignant transformation ,Subserous ,Gynecology and obstetrics ,RG1-991 ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
When a woman presents with an acute abdomen with cystic lesions in the abdominal cavity, the differential diagnosis includes torsion or rupture of an ovarian tumor. We report our experience with a 54-year-old nulliparous woman who underwent emergency surgery for a suspected ruptured ovarian tumor. Intraoperative examination revealed disruption of a cystic tumor that had developed externally from the fundus of the uterus. The patient, who was taking aspirin because of a history of medullary infarction, reported lower abdominal discomfort for several days. When she sought care, she was referred to the gynecology department where transvaginal ultrasonography and contrast-enhanced computed tomography showed a poorly toned mass with a maximum diameter of 20 cm posterior to the uterus. She also had a large amount of ascites reaching around the liver and the spleen.She underwent an emergency laparotomy for a presumed diagnosis of acute abdomen caused by a ruptured ovarian tumor with intra-abdominal bleeding. Intraoperative examination revealed normal adnexae bilaterally, but there was a cystic tumor in the pouch of Douglas that was strongly adherent to the surrounding intestines. This mass was connected to the posterior uterus by a stalk and appeared to be continuous with the uterine tissue. The postoperative pathological diagnosis was carcinosarcoma derived from subserous cystic adenomyosis. This is the first case report of carcinosarcoma developing from subserous cystic adenomyosis in the English literature as far as we know.
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- 2023
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3. Spontaneous rupture of the ovarian vein in association with nutcracker syndrome: a case report
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Akihito Yamamoto, Seiryu Kamoi, and Shunji Suzuki
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Nutcracker syndrome ,Nutcracker phenomenon ,Pelvic congestion syndrome ,Ovarian vein ,Gonadal vein ,Pelvic venous plexus ,Medicine - Abstract
Abstract Background Nutcracker syndrome is a condition in which the left renal vein is pinched between the abdominal aorta and the superior mesenteric artery, resulting in an increase in renal vein pressure and certain symptoms. We report a very rare case of retroperitoneal hematoma caused by the rupture of varicose veins of the left ovary. Case presentation A 77-year-old Japanese woman, para 7, experienced sudden left lower abdominal pain. She had no history of trauma or treatment complications. Computed tomography revealed a left retroperitoneal hematoma, but her abdominal pain subsided quickly; thus, urgent treatment was not required. We then scheduled her for an assessment regarding the cause of her bleeding. However, 6 days after the pain onset, abdominal pain symptoms recurred, confirming hematoma regrowth. Magnetic resonance imaging and three-dimensional computed tomography revealed an abnormal vascular network from the left side of the uterus to the left adnexa. Subsequent angiography revealed that the retroperitoneal bleeding originated from rupture of the distended left ovarian vein, which caused blood reflux from the left renal vein to the left ovarian vein. Although angiography confirmed a passage between the left renal vein and inferior vena cava, computed tomography showed obvious stenosis in the left renal vein. In accordance with these findings, we diagnosed the cause of the distention and rupture of the left ovarian vein as nutcracker syndrome. She underwent embolization of the left ovarian vein as hemostasis treatment, and had a good course thereafter. Conclusions This is the first report of a spontaneous rupture of the left ovarian vein caused by nutcracker syndrome. Nutcracker syndrome is not yet well known to clinicians and should be considered as part of the differential diagnosis when an abnormal vascular network in the pelvis is found.
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- 2021
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4. Conditioned medium from stem cells derived from human exfoliated deciduous teeth ameliorates NASH via the Gut-Liver axis
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Hisanori Muto, Takanori Ito, Taku Tanaka, Shinya Yokoyama, Kenta Yamamoto, Norihiro Imai, Yoji Ishizu, Keiko Maeda, Takashi Honda, Tetsuya Ishikawa, Asuka Kato, Taichi Ohshiro, Fumiya Kano, Akihito Yamamoto, Kiyoshi Sakai, Hideharu Hibi, Masatoshi Ishigami, and Mitsuhiro Fujishiro
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Medicine ,Science - Abstract
Abstract Non-alcoholic steatohepatitis (NASH) occurrence has been increasing and is becoming a major cause of liver cirrhosis and liver cancer. However, effective treatments for NASH are still lacking. We examined the benefits of serum-free conditioned medium from stem cells derived from human exfoliated deciduous teeth (SHED-CM) on a murine non-alcoholic steatohepatitis (NASH) model induced by a combination of Western diet (WD) and repeated administration of low doses of carbon tetrachloride intraperitoneally, focusing on the gut-liver axis. We showed that repeated intravenous administration of SHED-CM significantly ameliorated histological liver fibrosis and inflammation in a murine NASH model. SHED-CM inhibited parenchymal cell apoptosis and reduced the activation of inflammatory macrophages. Gene expression of pro-inflammatory and pro-fibrotic mediators (such as Tnf-α , Tgf-β, and Ccl-2) in the liver was reduced in mice treated with SHED-CM. Furthermore, SHED-CM protected intestinal tight junctions and maintained intestinal barrier function, while suppressing gene expression of the receptor for endotoxin, Toll-like receptor 4, in the liver. SHED-CM promoted the recovery of Caco-2 monolayer dysfunction induced by IFN-γ and TNF-α in vitro. Our findings suggest that SHED-CM may inhibit NASH fibrosis via the gut-liver axis, in addition to its protective effect on hepatocytes and the induction of macrophages with unique anti-inflammatory phenotypes.
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- 2021
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5. The immunoregulatory role of p21 in the development of the temporomandibular joint‐osteoarthritis
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Tsendsuren Khurel‐Ochir, Takashi Izawa, Akihiko Iwasa, Fumiya Kano, Akihito Yamamoto, and Eiji Tanaka
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chondrocyte ,metalloprotease ,osteoarthritis ,p21 ,temporomandibular joint ,Dentistry ,RK1-715 - Abstract
Abstract Objective We aimed to identify the immunoregulatory role of the cyclin‐dependent kinase inhibitor p21 in the homeostasis of mandibular condylar cartilage affected by mechanical stress. Materials and methods Ten C57BL/6 wild‐type (WT) and ten p21−/− mice aged 8 weeks were divided into the untreated and treated groups. In the treated groups, mechanical stress was applied to the temporomandibular joint (TMJ) through forced mouth opening for 3 hr/day for 7 days. The dissected TMJs were assessed using micro‐CT, histology, and immunohistochemistry. Results Treated p21−/− condyles with mechanical stress revealed more severe subchondral bone destruction, with thinner cartilage layers and smaller proteoglycan area relative to treated WT condyles; untreated WT and p21−/− condyles had smoother surfaces. Immunohistochemistry revealed significant increases in the numbers of caspase‐3, interleukin‐1β, matrix metalloprotease (MMP)‐9, and MMP‐13 positive cells, and few aggrecan positive cells, in treated p21−/− than in treated WT samples. Moreover, the number of TUNEL positive cells markedly increased in p21−/− condyles affected by mechanical stress. Conclusions Our findings indicate that p21 in chondrocytes contributes to regulate matrix synthesis via the control ofm aggrecan and MMP‐13 expression under mechanical stress. Thus, p21 might regulate the pathogenesis of osteoarthritis in the TMJ.
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- 2021
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6. Conditioned Medium From the Stem Cells of Human Exfoliated Deciduous Teeth Ameliorates Neuropathic Pain in a Partial Sciatic Nerve Ligation Model
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Yao Liu, Fumiya Kano, Noboru Hashimoto, Linze Xia, Qiao Zhou, Xingmei Feng, Hideharu Hibi, Aya Miyazaki, Tsutomu Iwamoto, Yoshizo Matsuka, Zhijun Zhang, Eiji Tanaka, and Akihito Yamamoto
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neuropathic pain ,dental pulp stem cells ,macrophage ,MCP-1 ,siglec-9 ,conditioned medium ,Therapeutics. Pharmacology ,RM1-950 - Abstract
In neuropathic pain (NP), injury or diseases of the somatosensory system often result in highly debilitating chronic pain. Currently, there is no effective drug for the complete and definitive treatment of NP. We investigated the therapeutic potential of conditioned medium (CM) derived from stem cells from human exfoliated deciduous teeth (SHED-CM) against NP using a mouse partial sciatic nerve ligation (PSL) model. Abnormal pain sensation, such as tactile allodynia and hyperalgesia, can be caused by PSL. In the behavioral test, intravenous administration of SHED-CM greatly improved the PSL-induced hypersensitivity. We found that treatment with SHED-CM resulted in the recruitment of M2 macrophages in the injured sciatic nerve and ipsilateral L4/L5 dorsal root ganglion and suppressed microglial activation in the spinal cord. Notably, specific depletion of the anti-inflammatory M2 macrophages by mannosylated-Clodrosome markedly reduced the antinociceptive effect of SHED-CM. Intravenous administration of CM from M2 induced by SHED-CM (M2-CM) ameliorated the PSL-induced hypersensitivity. We found that M2-CM directly suppressed the expression of nociceptive receptors as well as proinflammatory mediators in Schwann cells. Taken together, our data suggest that SHED-CM ameliorates NP through the induction of the analgesic anti-inflammatory M2 macrophages. Thus, SHED-CM may be a novel therapeutic candidate for NP.
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- 2022
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7. Stem Cells From Human Exfoliated Deciduous Teeth-Conditioned Medium (SHED-CM) is a Promising Treatment for Amyotrophic Lateral Sclerosis
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Tomoyuki Ueda, Taisei Ito, Masatoshi Inden, Hisaka Kurita, Akihito Yamamoto, and Isao Hozumi
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amyotrophic lateral sclerosis ,copper-zinc superoxide dismutase 1 ,stem cells from human exfoliated deciduous teeth ,induced pluripotent stem cells ,aggregation ,Therapeutics. Pharmacology ,RM1-950 - Abstract
Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disorder, characterized by the loss of upper and lower motor neurons, for which an effective treatment has yet to be developed. Previous reports have shown that excessive oxidative stress, related to mitochondrial dysfunction and the accumulation of misfolding protein, contributes to ALS pathology. In terms of treatment, it remains necessary to identify effective medicines for multiple therapeutic targets and have additive effects against several disorders. In this study, we investigated stem cells from human exfoliated deciduous teeth (SHED), which release many factors, such as neurotrophic factors and cytokines, and are applied to treat neurological diseases. Specifically, we examined whether SHED-conditioned medium (CM), i.e., the serum-free culture supernatant of SHED, reduced mutant SOD1-induced intracellular aggregates and neurotoxicity. We found that SHED-CM significantly suppressed the mutant SOD1-induced intracellular aggregates and neurotoxicity. The neuroprotective effects of SHED-CM are partly related to heat shock protein and the activation of insulin-like growth factor-1 receptor. SHED-CM also had a protective effect on induced pluripotent stem cell-derived motor neurons. Moreover, SHED-CM was effective against not only familial ALS but also sporadic ALS. Overall, these results suggest that SHED-CM could be a promising treatment for slowing the progression of ALS.
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- 2022
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8. Secreted factors from cultured dental pulp stem cells promoted neurite outgrowth of dorsal root ganglion neurons and ameliorated neural functions in streptozotocin‐induced diabetic mice
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Emiri Miura‐Yura, Shin Tsunekawa, Keiko Naruse, Nobuhisa Nakamura, Mikio Motegi, Hiromi Nakai‐Shimoda, Saeko Asano, Makoto Kato, Yuichiro Yamada, Takako Izumoto‐Akita, Akihito Yamamoto, Tatsuhito Himeno, Masaki Kondo, Yoshiro Kato, Jiro Nakamura, and Hideki Kamiya
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Conditioned medium ,Diabetic polyneuropathy ,Stem cells from human exfoliated deciduous teeth ,Diseases of the endocrine glands. Clinical endocrinology ,RC648-665 - Abstract
Abstract Aims/Introduction Transplantation of stem cells promotes axonal regeneration and angiogenesis in a paracrine manner. In the present study, we examined whether the secreted factors in conditioned medium of stem cells from human exfoliated deciduous teeth (SHED‐CM) had beneficial effects on diabetic polyneuropathy in mice. Materials and Methods Conditioned medium of stem cells from human exfoliated deciduous teeth was collected 48 h after culturing in serum‐free Dulbecco's modified Eagle's medium (DMEM), and separated into four fractions according to molecular weight. Dorsal root ganglion neurons from C57BL/6J mice were cultured with SHED‐CM or DMEM to evaluate the effect on neurite outgrowth. Streptozotocin‐induced diabetic mice were injected with 100 μL of SHED‐CM or DMEM into the unilateral hindlimb muscles twice a week over a period of 4 weeks. Peripheral nerve functions were evaluated by the plantar test, and motor and sensory nerve conduction velocities. Intraepidermal nerve fiber densities, capillary number‐to‐muscle fiber ratio, capillary blood flow and morphometry of sural nerves were also evaluated. Results Conditioned medium of stem cells from human exfoliated deciduous teeth significantly promoted neurite outgrowth of dorsal root ganglion neurons compared with DMEM. Among four fractions of SHED‐CM, the only fraction of
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- 2020
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9. Efficacy and Adverse Events of Carboplatin Desensitisation Therapy for Gynaecological Cancer: A Retrospective Study
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Akihito Yamamoto, Seiryu Kamoi, Shigeru Matsuda, Rieko Kawase, Kazuho Nakanishi, and Shunji Suzuki
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carboplatin ,desensitisation ,hypersensitivity ,malignancy ,gynaecology ,therapeutic effects ,Medicine - Abstract
Background: Carboplatin, the key drug used in treating gynaecological cancer, has an approximately 12–16% risk of hypersensitivity reactions. We aimed to investigate the efficacy and adverse effects of carboplatin desensitisation therapy for gynaecological cancer. Methods: The desensitisation protocol was standardised as a four-step, 4-h, carboplatin administration in the hospital. A retrospective medical record review was conducted on 15 patients who underwent carboplatin desensitisation for gynaecological malignancies at our hospital. Patients’ data were analysed to evaluate the treatment success rate, therapeutic effect of desensitisation, adverse events, and treatment. Results: Of 91 carboplatin desensitisation cycles scheduled; the completion rate was 93.4% (85/91). Adverse events occurred in 23 of these 91 (25.3%). In four (4.4%) of the 23 cycles, hypersensitivity reactions could be treated only by discontinuing the infusion and slowing the administration, while in the remaining 19 (20.9%), medication was administered intravenously after discontinuing the infusion to manage hypersensitivity reactions. No treatment-related deaths occurred. Overall, 23 series of anti-cancer agent regimens, including carboplatin desensitisation, were administered to the 15 patients. The therapeutic response rate was 82.6% and the disease control rate was 95.7%. Conclusions: Carboplatin desensitisation was beneficial in patients with a history of carboplatin-induced hypersensitivity reactions.
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- 2022
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10. Peripherally Administered Botulinum Toxin Type A Localizes Bilaterally in Trigeminal Ganglia of Animal Model
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Arief Waskitho, Yumiko Yamamoto, Swarnalakshmi Raman, Fumiya Kano, Huijiao Yan, Resmi Raju, Shaista Afroz, Tsuyoshi Morita, Daisuke Ikutame, Kazuo Okura, Masamitsu Oshima, Akihito Yamamoto, Otto Baba, and Yoshizo Matsuka
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botulinum toxin ,trigeminal ganglion ,neuropathic pain ,Medicine - Abstract
Peripheral nerve injury leads to sensory ganglion hyperexcitation, which increases neurotransmitter release and neuropathic pain. Botulinum toxin type A (BoNT/A) regulates pain transmission by reducing neurotransmitter release, thereby attenuating neuropathic pain. Despite multiple studies on the use of BoNT/A for managing neuropathic pain in the orofacial region, its exact mechanism of transport remains unclear. In this study, we investigated the effects of BoNT/A in managing neuropathic pain in two different animal models and its transport mechanism in the trigeminal nerve. Intraperitoneal administration of cisplatin induced bilateral neuropathic pain in the orofacial region, reducing the head withdrawal threshold to mechanical stimulation. Unilateral infraorbital nerve constriction (IONC) also reduced the ipsilateral head withdrawal threshold to mechanical stimulation. Unilateral peripheral administration of BoNT/A to the rat whisker pad attenuated cisplatin-induced pain behavior bilaterally. Furthermore, contralateral peripheral administration of BoNT/A attenuated neuropathy-induced behavior caused by IONC. We also noted the presence of BoNT/A in the blood using the mouse bioassay. In addition, the Alexa Fluor-488-labeled C-terminal half of the heavy chain of BoNT/A (BoNT/A-Hc) was localized in the neurons of the bilateral trigeminal ganglia following its unilateral administration. These findings suggest that axonal and hematogenous transport are involved in the therapeutic effects of peripherally administered BoNT/A in the orofacial region.
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- 2021
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11. Secreted Factors from Stem Cells of Human Exfoliated Deciduous Teeth Directly Activate Endothelial Cells to Promote All Processes of Angiogenesis
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Makoto Kato, Shin Tsunekawa, Nobuhisa Nakamura, Emiri Miura-Yura, Yuichiro Yamada, Yusuke Hayashi, Hiromi Nakai-Shimoda, Saeko Asano, Tomohide Hayami, Mikio Motegi, Emi Asano-Hayami, Sachiko Sasajima, Yoshiaki Morishita, Tatsuhito Himeno, Masaki Kondo, Yoshiro Kato, Takako Izumoto-Akita, Akihito Yamamoto, Keiko Naruse, Jiro Nakamura, and Hideki Kamiya
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angiogenesis ,endothelial cell ,SHED ,conditioned medium ,Cytology ,QH573-671 - Abstract
Diabetes is a major risk factor for atherosclerosis and ischemic vascular diseases. Recently, regenerative medicine is expected to be a novel therapy for ischemic diseases. Our previous studies have reported that transplantation of stem cells promoted therapeutic angiogenesis for diabetic neuropathy and ischemic vascular disease in a paracrine manner, but the precise mechanism is unclear. Therefore, we examined whether secreted factors from stem cells had direct beneficial effects on endothelial cells to promote angiogenesis. The soluble factors were collected as conditioned medium (CM) 48 h after culturing stem cells from human exfoliated deciduous teeth (SHED) in serum-free DMEM. SHED-CM significantly increased cell viability of human umbilical vein endothelial cells (HUVECs) in MTT assays and accelerated HUVECs migration in wound healing and Boyden chamber assays. In a Matrigel plug assay of mice, the migrated number of primary endothelial cells was markedly increased in the plug containing SHED-CM or SHED suspension. SHED-CM induced complex tubular structures of HUVECs in a tube formation assay. Furthermore, SHED-CM significantly increased neovascularization from the primary rat aorta, indicating that SHED-CM stimulated primary endothelial cells to promote comprehensive angiogenesis processes. The angiogenic effects of SHED-CM were the same or greater than the effective concentration of VEGF. In conclusion, SHED-CM directly stimulates vascular endothelial cells to promote angiogenesis and is promising for future clinical application.
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- 2020
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12. Allelic Imbalance in Regulation of ANRIL through Chromatin Interaction at 9p21 Endometriosis Risk Locus.
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Hirofumi Nakaoka, Aishwarya Gurumurthy, Takahide Hayano, Somayeh Ahmadloo, Waleed H Omer, Kosuke Yoshihara, Akihito Yamamoto, Keisuke Kurose, Takayuki Enomoto, Shigeo Akira, Kazuyoshi Hosomichi, and Ituro Inoue
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Genetics ,QH426-470 - Abstract
Genome-wide association studies (GWASs) have discovered numerous single nucleotide polymorphisms (SNPs) associated with human complex disorders. However, functional characterization of the disease-associated SNPs remains a formidable challenge. Here we explored regulatory mechanism of a SNP on chromosome 9p21 associated with endometriosis by leveraging "allele-specific" functional genomic approaches. By re-sequencing 1.29 Mb of 9p21 region and scrutinizing DNase-seq data from the ENCODE project, we prioritized rs17761446 as a candidate functional variant that was in perfect linkage disequilibrium with the original GWAS SNP (rs10965235) and located on DNase I hypersensitive site. Chromosome conformation capture followed by high-throughput sequencing revealed that the protective G allele of rs17761446 exerted stronger chromatin interaction with ANRIL promoter. We demonstrated that the protective allele exhibited preferential binding affinities to TCF7L2 and EP300 by bioinformatics and chromatin immunoprecipitation (ChIP) analyses. ChIP assays for histone H3 lysine 27 acetylation and RNA polymerase II reinforced the enhancer activity of the SNP site. The allele specific expression analysis for eutopic endometrial tissues and endometrial carcinoma cell lines showed that rs17761446 was a cis-regulatory variant where G allele was associated with increased ANRIL expression. Our work illuminates the allelic imbalances in a series of transcriptional regulation from factor binding to gene expression mediated by chromatin interaction underlie the molecular mechanism of 9p21 endometriosis risk locus. Functional genomics on common disease will unlock functional aspect of genotype-phenotype correlations in the post-GWAS stage.
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- 2016
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13. Correction: Therapeutic Potential of Stem Cells from Human Exfoliated Deciduous Teeth in Models of Acute Kidney Injury.
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Yuka Hattori, Hangsoo Kim, Naotake Tsuboi, Akihito Yamamoto, Shinichi Akiyama, Yiqin Shi, Takayuki Katsuno, Tomoki Kosugi, Minoru Ueda, Seiichi Matsuo, and Shoichi Maruyama
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Medicine ,Science - Published
- 2015
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14. Therapeutic Potential of Stem Cells from Human Exfoliated Deciduous Teeth in Models of Acute Kidney Injury.
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Yuka Hattori, Hangsoo Kim, Naotake Tsuboi, Akihito Yamamoto, Shinichi Akiyama, Yiqin Shi, Takayuki Katsuno, Tomoki Kosugi, Minoru Ueda, Seiichi Matsuo, and Shoichi Maruyama
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Medicine ,Science - Abstract
Acute kidney injury (AKI) is a critical condition associated with high mortality. However, the available treatments for AKI are limited. Stem cells from human exfoliated deciduous teeth (SHED) have recently gained attention as a novel source of stem cells. The purpose of this study was to clarify whether SHED have a therapeutic effect on AKI induced by ischemia-reperfusion injury.The left renal artery and vein of the mice were clamped for 20 min to induce ischemia. SHED, bone marrow derived mesenchymal stem cells (BMMSC) or phosphate-buffered saline (control) were administered into the subrenal capsule. To confirm the potency of SHED in vitro, H2O2 stimulation assays and scratch assays were performed.The serum creatinine and blood urea nitrogen levels of the SHED group were significantly lower than those of the control group, while BMMSC showed no therapeutic effect. Infiltration of macrophages and neutrophils in the kidney was significantly attenuated in mice treated with SHED. Cytokine levels (MIP-2, IL-1β, and MCP-1) in mice kidneys were significantly reduced in the SHED group. In in vitro experiments, SHED significantly decreased MCP-1 secretion in tubular epithelial cells (TEC) stimulated with H2O2. In addition, SHED promoted wound healing in the scratch assays, which was blunted by anti-HGF antibodies.SHED attenuated the levels of inflammatory cytokines and improved kidney function in AKI induced by IRI. SHED secreted factors reduced MCP-1 and increased HGF expression, which promoted wound healing. These results suggest that SHED might provide a novel stem cell resource, which can be applied for the treatment of ischemic kidney injury.
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- 2015
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15. Iroquois homeobox 3 regulates odontoblast proliferation and differentiation mediated by Wnt5a expression
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Anrizandy Narwidina, Aya Miyazaki, Kokoro Iwata, Rika Kurogoushi, Asuna Sugimoto, Yasusei Kudo, Keita Kawarabayashi, Yoshihito Yamakawa, Yuki Akazawa, Takamasa Kitamura, Hiroshi Nakagawa, Kimiko Yamaguchi-Ueda, Tomokazu Hasegawa, Keigo Yoshizaki, Satoshi Fukumoto, Akihito Yamamoto, Naozumi Ishimaru, Tomonori Iwasaki, and Tsutomu Iwamoto
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Odontoblasts ,Cell differentiation ,Biophysics ,Irx3 ,Cell Biology ,Wnt5a ,Molecular Biology ,Biochemistry ,Iroquois homeobox genes ,Cell proliferation - Abstract
Iroquois homeobox (Irx) genes are TALE-class homeobox genes that are evolutionarily conserved across species and have multiple critical cellular functions in fundamental tissue development processes. Previous studies have shown that Irxs genes are expressed during tooth development. However, the precise roles of genes in teeth remain unclear. Here, we demonstrated for the first time that Irx3 is an essential molecule for the proliferation and differentiation of odontoblasts. Using cDNA synthesized from postnatal day 1 (P1) tooth germs, we examined the expression of all Irx genes (Irx1-Irx6) by RT-PCR and found that all genes except Irx4 were expressed in the tooth tissue. Irx1-Irx3 a were expressed in the dental epithelial cell line M3H1 cells, while Irx3 and Irx5 were expressed in the dental mesenchymal cell line mDP cells. Only Irx3 was expressed in both undifferentiated cell lines. Immunostaining also revealed the presence of IRX3 in the dental epithelial cells and mesenchymal condensation. Inhibition of endogenous Irx3 by siRNA blocks the proliferation and differentiation of mDP cells. Wnt3a, Wnt5a, and Bmp4 are factors involved in odontoblast differentiation and were highly expressed in mDP cells by quantitative PCR analysis. Interestingly, the expression of Wnt5a (but not Wnt3a or Bmp4) was suppressed by Irx3 siRNA. These results suggest that Irx3 plays an essential role in part through the regulation of Wnt5a expression during odontoblast proliferation and differentiation.
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- 2023
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16. Improving Accuracy of Printed Character Recognition Using Hexagonal Zoning of Directional Histogram Feature.
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Wataru Ohyama, Akihito Yamamoto, Tetsushi Wakabayashi, and Fumitaka Kimura
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- 2014
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17. von Willebrand factor D and EGF domains regulate ameloblast differentiation and enamel formation
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Kokoro Iwata, Keita Kawarabayashi, Keigo Yoshizaki, Tian Tian, Kan Saito, Asuna Sugimoto, Rika Kurogoushi, Aya Yamada, Akihito Yamamoto, Yasuei Kudo, Naozumi Ishimaru, Satoshi Fukumoto, and Tsutomu Iwamoto
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Mice, Knockout ,Extracellular Matrix Proteins ,Mice ,Physiology ,Clinical Biochemistry ,Ameloblasts ,Animals ,Cell Differentiation ,Cell Biology ,Cadherins ,Dental Enamel - Abstract
Cell- and tissue-specific extracellular matrix (ECM) composition plays an important role in organ development, including teeth, by regulating cell behaviors, such as cell proliferation and differentiation. Here, we demonstrate for the first time that von Willebrand factor D and epidermal growth factor (EGF) domains (Vwde), a previously uncharacterized ECM protein, is specifically expressed in teeth and regulates cell proliferation and differentiation in inner enamel epithelial cells (IEEs) and enamel formation. We identified the Vwde as a novel ECM protein through bioinformatics using the NCBI expressed sequence tag database for mice. Vwde complementary DNA encodes 1773 amino acids containing a signal peptide, a von Willebrand factor type D domain, and tandem calcium-binding EGF-like domains. Real-time polymerase chain reaction demonstrated that Vwde is highly expressed in tooth tissue but not in other tissues including the brain, lung, heart, liver, kidney, and bone. In situ hybridization revealed that the IEEs expressed Vwde messenger RNA in developing teeth. Immunostaining showed that VWDE was localized at the proximal and the distal ends of the pericellular regions of the IEEs. Vwde was induced during the differentiation of mouse dental epithelium-derived M3H1 cells. Vwde-transfected M3H1 cells secreted VWDE protein into the culture medium and inhibited cell proliferation, whereas ameloblastic differentiation was promoted. Furthermore, Vwde increased the phosphorylation of extracellular signal-regulated kinase 1/2 and protein kinase B and strongly induced the expression of the intercellular junction protein, N-cadherin (Ncad). Interestingly, the suppression of endogenous Vwde inhibited the expression of Ncad. Finally, we created Vwde-knockout mice using the CRISPR-Cas9 system. Vwde-null mice showed low mineral density, rough surface, and cracks in the enamel, indicating the enamel hypoplasia phenotype. Our findings suggest that Vwde assembling the matrix underneath the IEEs is essential for Ncad expression and enamel formation.
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- 2021
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18. 23.5 A 4Gb LPDDR2 STT-MRAM with compact 9F2 1T1MTJ cell and hierarchical bitline architecture.
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Kwangmyoung Rho, Kenji Tsuchida, Dongkeun Kim, Yutaka Shirai, Jihyae Bae, Tsuneo Inaba, Hiromi Noro, Hyunin Moon, Sungwoong Chung, Kazumasa Sunouchi, Jinwon Park, Kiseon Park, Akihito Yamamoto, Seoungju Chung, Hyeongon Kim, Hisato Oyamatsu, and Jonghoon Oh
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- 2017
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19. Effectiveness and Long-term Outcomes of Nerve-Sparing Radical Hysterectomy for Cervical Cancer
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Akihito, Yamamoto, Seiryu, Kamoi, Mariko, Ikeda, Takashi, Yamada, Koichi, Yoneyama, Toshiyuki, Takeshita, Yamamoto, Akihito, Kamoi, Seiryu, Ikeda, Mariko, Yamada, Takashi, Yoneyama, Koichi, and Takeshita, Toshiyuki
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Adult ,medicine.medical_specialty ,Urinary system ,medicine.medical_treatment ,Uterine Cervical Neoplasms ,Hysterectomy ,Pelvis ,Postoperative Complications ,medicine ,Humans ,Radical surgery ,Radical Hysterectomy ,Survival rate ,Retrospective Studies ,Cervical cancer ,business.industry ,Urination disorder ,General Medicine ,Middle Aged ,Urination Disorders ,Urinary function ,medicine.disease ,Surgery ,Carcinoma, Squamous Cell ,Quality of Life ,Female ,business ,Organ Sparing Treatments ,Follow-Up Studies - Abstract
BackgroundRadical hysterectomy (RH) is a type of radical surgery performed for cervical cancer. Urinary dysfunction due to RH exacerbates the postoperative quality of life of cervical cancer patients. The nerve-sparing RH (NSRH) technique has been used as an effective measure to conserve urinary function. However, few reports have been published on the long-term prognosis. This study described performance of our nerve-sparing technique and the long-term prognosis of patients.MethodsSixty-one patients underwent radical hysterectomy in a 5-year period during which the nerve-sparing technique was introduced; of these, 31 patients underwent NSRH and 30 underwent conventional RH. We retrospectively examined the medical records and compared postoperative urinary function and treatment outcome between the two groups.ResultsThe median time required for urinary residual volume to fall to ≤50 ml after removal of the urinary catheter was 6 days (range, 2-20 days) in the NSRH group and 13.5 days (range, 3-46 days) in the RH group. The results were significantly better in the NSRH group (p < 0.05). The mean follow-up period was 2,456.3 days (range, 48-4,213 days). Investigations on curability revealed no significant difference between the two groups in local recurrence and long-term survival rates. The 5-year survival rate was 0.861 in the NSRH group and 0.782 in the RH group; the 10-year survival rate was 0.861 in the NSRH group and 0.679 in the RH group.ConclusionsSurgical procedures for NSRH significantly improved postoperative urinary function without deteriorating local recurrence rates and long-term prognosis.
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- 2021
20. Effectiveness of low-intensity pulsed ultrasound on osteoarthritis of the temporomandibular joint: A review
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Yao Liu, Akihito Yamamoto, Noboru Hashimoto, Eiji Tanaka, Xingmei Feng, Takuma Sakamaki, Naoko Ogasawara, Linze Xia, and Fumiya Kano
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Orthodontics ,Temporomandibular Joint ,business.industry ,Ultrasonic Therapy ,Cartilage ,Regeneration (biology) ,Mandibular Condyle ,Biomedical Engineering ,Bone healing ,Osteoarthritis ,Low-intensity pulsed ultrasound ,medicine.disease ,Condyle ,Temporomandibular joint ,Occlusal Splints ,stomatognathic diseases ,medicine.anatomical_structure ,Ultrasonic Waves ,stomatognathic system ,medicine ,Humans ,business - Abstract
Loading is indispensable for the growth, development, and maintenance of joint tissues, including mandibular condylar cartilage, but excessive loading or reduced host adaptive capacity can considerably damage the temporomandibular joint (TMJ), leading to temporomandibular joint osteoarthritis (TMJ-OA). TMJ-OA, associated with other pathological conditions and aging processes, is a highly degenerative disease affecting the articular cartilage. Many treatment modalities for TMJ-OA have been developed. Traditional clinical treatment includes mainly nonsurgical options, such as occlusal splints. However, non-invasive therapy does not achieve joint tissue repair and regeneration. Growing evidence suggests that low-intensity pulsed ultrasound (LIPUS) accelerates bone fracture healing and regeneration, as well as having extraordinary effects in terms of soft tissue repair and regeneration. The latter have received much attention, and various studies have been performed to evaluate the potential role of LIPUS in tissue regeneration including that applied to articular cartilage. The present article provides an overview of the status of LIPUS stimulation used to prevent the onset and progression of TMJ-OA and enhance the tissue regeneration of mandibular condylar cartilage. The etiology and management of TMJ-OA are explained briefly, animal models of TMJ-OA are described, and the effectiveness of LIPUS on cell metabolism and tissue regeneration in the TMJ is discussed.
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- 2020
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21. Factors secreted from dental pulp stem cells show multifaceted benefits for treating experimental temporomandibular joint osteoarthritis
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Naoko Ogasawara, Noboru Hashimoto, Linze Xia, Eiji Tanaka, Akihito Yamamoto, Tsutomu Iwamoto, Yao Liu, Takuma Sakamaki, Fumiya Kano, Hideharu Hibi, and Hiroki Mori
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Male ,0301 basic medicine ,Pathology ,medicine.medical_specialty ,Biomedical Engineering ,Osteoarthritis ,Bone remodeling ,Mice ,03 medical and health sciences ,0302 clinical medicine ,Rheumatology ,Dental pulp stem cells ,Animals ,Humans ,Medicine ,Orthopedics and Sports Medicine ,Dental Pulp ,030203 arthritis & rheumatology ,Biological Products ,TUNEL assay ,Temporomandibular Joint ,business.industry ,Stem Cells ,Cartilage ,Regeneration (biology) ,medicine.disease ,Temporomandibular joint ,Disease Models, Animal ,030104 developmental biology ,medicine.anatomical_structure ,Stem cell ,business - Abstract
Summary Objective Temporomandibular joint osteoarthritis (TMJOA) is a degenerative disease characterized by progressive cartilage degeneration, abnormal bone remodeling, and chronic pain. In this study, we aimed to investigate effective therapies to reverse or suppress TMJOA progression. Design To this end, we performed intravenous administration of serum free conditioned media from human exfoliated deciduous teeth stem cells (SHED-CM) into a mechanical-stress induced murine TMJOA model. Results SHED-CM administration markedly suppressed temporal muscle inflammation, and improved bone integrity and surface smoothness of the destroyed condylar cartilage. Moreover, SHED-CM treatment decreased the number of IL-1β, iNOS, and MMP-13 expressing chondrocytes, whereas it specifically increased PCNA-positive cells in the multipotent polymorphic cell layer. Notably, the numbers of TdT-mediated dUTP nick end labeling (TUNEL)-positive apoptotic chondrocytes in the SHED-CM treated condyles were significantly lower than in those treated with DMEM, whereas the proteoglycan positive area was restored to a level similar to that of the sham treated group, demonstrating that SHED-CM treatment regenerated the mechanical-stress injured condylar cartilage and subchondral bone. Secretome analysis revealed that SHED-CM contained multiple therapeutic factors that act in osteochondral regeneration. Conclusions Our data demonstrated that SHED-CM treatment promoted the regeneration and repair of mechanical-stress induced mouse TMJOA. Our observations suggest that SHED-CM has potential to be a potent tissue-regenerating therapeutic agent for patients with severe TMJOA.
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- 2020
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22. Case of ovarian steroid cell tumor diagnosed after presenting acute heart failure
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Yuu Yamaguchi, Hanako Kaseki, Shigeru Matsuda, Kenichiro Watanabe, Shigeo Akira, Akihito Yamamoto, Shuichi Ono, Toshiyuki Takeshita, and Masao Ichikawa
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medicine.medical_specialty ,business.industry ,Virilization ,Obstetrics and Gynecology ,medicine.disease ,Surgery ,Menstruation ,Ovarian tumor ,Heart failure ,medicine ,Histopathology ,Exertion ,Ovarian Steroid Cell Tumor ,medicine.symptom ,business ,hirsutism - Abstract
We report a rare case of an ovarian steroid cell tumor with a diagnosis prompted by heart failure symptoms. A 28-year-old Japanese nulligravida/nullipara with a chief complaint of respiratory discomfort during physical exertion and exhibiting heart failure symptoms was referred to our hospital. She also had signs of virilization, including secondary menorrhea since the age of 20, hirsutism and balding. Cushing's syndrome was suspected, and further examinations showed hypertestosteronemia and right ovarian tumor. Symptomatic treatment for heart failure with diuretics and antihypertensives was followed by abdominal right adnexectomy performed due to the androgen-producing ovarian tumor. The tumor was solid and larger than a fist, and confirmed as a steroid cell tumor through postoperative histopathology. Serum total testosterone levels normalized at day 3 postoperatively, and menstruation resumed 2 months later. Our case was diagnosed due to heart failure symptoms, and its treatment resulted in improvement in virilization signs.
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- 2020
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23. Effectiveness and Long-term Outcomes of Nerve-Sparing Radical Hysterectomy for Cervical Cancer
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Akihito, Yamamoto, Seiryu, Kamoi, Mariko, Ikeda, Takashi, Yamada, Koichi, Yoneyama, Toshiyuki, Takeshita, Yamamoto, Akihito, Kamoi, Seiryu, Ikeda, Mariko, Yamada, Takashi, Yoneyama, Koichi, Takeshita, Toshiyuki, Akihito, Yamamoto, Seiryu, Kamoi, Mariko, Ikeda, Takashi, Yamada, Koichi, Yoneyama, Toshiyuki, Takeshita, Yamamoto, Akihito, Kamoi, Seiryu, Ikeda, Mariko, Yamada, Takashi, Yoneyama, Koichi, and Takeshita, Toshiyuki
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source:https://www.nms.ac.jp/sh/jnms/2021/088050386.pdf
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- 2022
24. Cover Image, Volume 237, Number 3, March 2022
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Kokoro Iwata, Keita Kawarabayashi, Keigo Yoshizaki, Tian Tian, Kan Saito, Asuna Sugimoto, Rika Kurogoushi, Aya Yamada, Akihito Yamamoto, Yasuei Kudo, Naozumi Ishimaru, Satoshi Fukumoto, and Tsutomu Iwamoto
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Physiology ,Clinical Biochemistry ,Cell Biology - Published
- 2022
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25. Preoperative screening endometrial cytology discovered incidental gynaecological malignancy in two patients undergoing risk-reducing salpingo-oophorectomy
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Riho Kojima, Masafumi Toyoshima, Akihito Yamamoto, and Shunji Suzuki
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General Medicine - Abstract
Pelvic ultrasonography and measurement of serum cancer antigen 125 (CA-125) are recommended for preoperative evaluation before performing risk-reducing salpingo-oophorectomy (RRSO). We report our experience with two patients in whom an incidental gynaecological malignancy was found using endometrial cytology as a preoperative screening test for RRSO. Patient 1 was an early 50s woman with a pathologic variant ofBRCA1. Transvaginal ultrasonography showed no endometrial abnormalities, but preoperative endometrial cytology revealed high-grade serous carcinoma. The patient underwent total hysterectomy, bilateral adnexectomy, pelvic and para-aortic lymph node dissection, and omentectomy. Patient 2 was a late 40s woman with a pathological variant ofBRCA1. Transvaginal ultrasonography showed mild enlargement of the left ovary, and her CA-125 level was elevated. Preoperative endometrial cytology revealed high-grade serous cancer. She underwent total hysterectomy, bilateral adnexectomy and omentectomy. These case reports illustrate the importance of preoperative screening—including endometrial cytology—before performing RRSO.
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- 2023
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26. 片側末梢投与されたA型ボツリヌス毒素は動物モデルにおいて両側三叉神経節に局在する
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Akihito Yamamoto, Yumiko Yamamoto, Daisuke Ikutame, Masamitsu Oshima, Kazuo Okura, Shaista Afroz, Yoshizo Matsuka, Huijiao Yan, Resmi Raju, Otto Baba, Arief Waskitho, Tsuyoshi Morita, Fumiya Kano, and Swarnalakshmi Raman
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Male ,trigeminal ganglion ,Health, Toxicology and Mutagenesis ,Stimulation ,Pharmacology ,Toxicology ,Article ,Rats, Sprague-Dawley ,Trigeminal ganglion ,Infraorbital nerve ,Mice ,medicine ,Animals ,botulinum toxin ,Botulinum Toxins, Type A ,Trigeminal nerve ,neuropathic pain ,Mice, Inbred ICR ,business.industry ,Botulinum toxin ,Rats ,Disease Models, Animal ,Sensory Ganglion ,Peripheral nerve injury ,Neuropathic pain ,Neuralgia ,Medicine ,Female ,business ,medicine.drug - Abstract
Peripheral nerve injury leads to sensory ganglion hyperexcitation, which increases neurotransmitter release and neuropathic pain. Botulinum toxin type A (BoNT/A) regulates pain transmission by reducing neurotransmitter release, thereby attenuating neuropathic pain. Despite multiple studies on the use of BoNT/A for managing neuropathic pain in the orofacial region, its exact mechanism of transport remains unclear. In this study, we investigated the effects of BoNT/A in managing neuropathic pain in two different animal models and its transport mechanism in the trigeminal nerve. Intraperitoneal administration of cisplatin induced bilateral neuropathic pain in the orofacial region, reducing the head withdrawal threshold to mechanical stimulation. Unilateral infraorbital nerve constriction (IONC) also reduced the ipsilateral head withdrawal threshold to mechanical stimulation. Unilateral peripheral administration of BoNT/A to the rat whisker pad attenuated cisplatin-induced pain behavior bilaterally. Furthermore, contralateral peripheral administration of BoNT/A attenuated neuropathy-induced behavior caused by IONC. We also noted the presence of BoNT/A in the blood using the mouse bioassay. In addition, the Alexa Fluor-488-labeled C-terminal half of the heavy chain of BoNT/A (BoNT/A-Hc) was localized in the neurons of the bilateral trigeminal ganglia following its unilateral administration. These findings suggest that axonal and hematogenous transport are involved in the therapeutic effects of peripherally administered BoNT/A in the orofacial region.
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- 2021
27. Effect of the Adoption of Metronidazole Injection Formulation on the Use of Meropenem and Tazobactam/piperacillin
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Keita Sakaguchi, Ayako Matsumura, Masashi Toyoda, Sachiko Okuyama, Akihito Yamamoto, Hiroyuki Jinnai, Megumi Andou, and Akemi Kataoka
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business.industry ,Tazobactam piperacillin ,Anesthesia ,medicine ,MetroNIDAZOLE Injection ,business ,Meropenem ,medicine.drug - Published
- 2020
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28. A Novel Treatment with Stem Cells from Human Exfoliated Deciduous Teeth for Hypoxic-Ischemic Encephalopathy in Neonatal Rats
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Yuichiro Sugiyama, Toshihiko Suzuki, Alkisti Mikrogeorgiou, Akihito Yamamoto, Hiroshi Yukawa, Masahiro Tsuji, Kohki Matsubara, Hitoshi Hirata, Shinobu Shimizu, Kazuto Ueda, Yoshinobu Baba, Masahiro Hayakawa, Yuka Tsukagoshi Okabe, Yuma Kitase, Yoshiyuki Takahashi, and Yoshiaki Sato
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Male ,0301 basic medicine ,Pathology ,medicine.medical_specialty ,Transplantation, Heterologous ,Encephalopathy ,Neurological disorder ,Motor Activity ,Biology ,Mesenchymal Stem Cell Transplantation ,medicine.disease_cause ,Hypoxic Ischemic Encephalopathy ,Cell therapy ,03 medical and health sciences ,0302 clinical medicine ,Avoidance Learning ,Deciduous teeth ,medicine ,Animals ,Humans ,Rats, Wistar ,Tooth, Deciduous ,Child ,Cells, Cultured ,Mesenchymal Stem Cells ,Cell Biology ,Hematology ,medicine.disease ,Disease Models, Animal ,Treatment Outcome ,030104 developmental biology ,medicine.anatomical_structure ,Animals, Newborn ,Hypoxia-Ischemia, Brain ,Administration, Intravenous ,Perinatal hypoxic - ischemic encephalopathy ,Microglia ,Stem cell ,030217 neurology & neurosurgery ,Oxidative stress ,Developmental Biology - Abstract
Recently, cell therapy has been developed as a novel treatment for perinatal hypoxic-ischemic encephalopathy (HIE), which is an important cause of neurological disorder and death, and stem cells from human exfoliated deciduous teeth (SHED) express early markers for mesenchymal and neuroectodermal stem cells. We investigated the treatment effect of SHED for HIE in neonatal rats. Seven-day-old rats underwent ligation of the left carotid artery and were exposed to 8% hypoxic treatment. SHED (1 × 10
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- 2020
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29. Secreted factors from cultured dental pulp stem cells promoted neurite outgrowth of dorsal root ganglion neurons and ameliorated neural functions in streptozotocin‐induced diabetic mice
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Shin Tsunekawa, Keiko Naruse, Tatsuhito Himeno, Mikio Motegi, Hiromi Nakai-Shimoda, Hideki Kamiya, Nobuhisa Nakamura, Yoshiro Kato, Jiro Nakamura, Saeko Asano, Masaki Kondo, Makoto Kato, Takako Izumoto-Akita, Yuichiro Yamada, Emiri Miura-Yura, and Akihito Yamamoto
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Male ,0301 basic medicine ,Basic Science and Research ,medicine.medical_specialty ,Diabetic polyneuropathy ,Neurite ,Endocrinology, Diabetes and Metabolism ,Neuronal Outgrowth ,Nerve fiber ,Diseases of the endocrine glands. Clinical endocrinology ,Diabetes Mellitus, Experimental ,Mice ,03 medical and health sciences ,0302 clinical medicine ,Diabetic Neuropathies ,Dorsal root ganglion ,Ganglia, Spinal ,Internal medicine ,Dental pulp stem cells ,Internal Medicine ,medicine ,Animals ,Conditioned medium ,Dental Pulp ,Neurons ,business.industry ,Stem cells from human exfoliated deciduous teeth ,Stem Cells ,Articles ,General Medicine ,Streptozotocin ,RC648-665 ,Mice, Inbred C57BL ,Transplantation ,030104 developmental biology ,medicine.anatomical_structure ,Endocrinology ,Original Article ,Stem cell ,business ,030217 neurology & neurosurgery ,Stem Cell Transplantation ,medicine.drug ,Sensory nerve - Abstract
Aims/Introduction Transplantation of stem cells promotes axonal regeneration and angiogenesis in a paracrine manner. In the present study, we examined whether the secreted factors in conditioned medium of stem cells from human exfoliated deciduous teeth (SHED‐CM) had beneficial effects on diabetic polyneuropathy in mice. Materials and Methods Conditioned medium of stem cells from human exfoliated deciduous teeth was collected 48 h after culturing in serum‐free Dulbecco's modified Eagle's medium (DMEM), and separated into four fractions according to molecular weight. Dorsal root ganglion neurons from C57BL/6J mice were cultured with SHED‐CM or DMEM to evaluate the effect on neurite outgrowth. Streptozotocin‐induced diabetic mice were injected with 100 μL of SHED‐CM or DMEM into the unilateral hindlimb muscles twice a week over a period of 4 weeks. Peripheral nerve functions were evaluated by the plantar test, and motor and sensory nerve conduction velocities. Intraepidermal nerve fiber densities, capillary number‐to‐muscle fiber ratio, capillary blood flow and morphometry of sural nerves were also evaluated. Results Conditioned medium of stem cells from human exfoliated deciduous teeth significantly promoted neurite outgrowth of dorsal root ganglion neurons compared with DMEM. Among four fractions of SHED‐CM, the only fraction of, In this study, we examined whether the secreted factors could be collected from conditioned medium of stem cells from human exfoliated deciduous teeth had beneficial effects on diabetic polyneuropathy. Conditioned medium of stem cells from human exfoliated deciduous teeth might have a therapeutic effect on diabetic polyneuropathy through promoting neurite outgrowth, and the increase in capillaries might contribute to the improvement of neural function.
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- 2020
30. The ceramide moiety of disialoganglioside (GD3) is essential for GD3 recognition by the sialic acid–binding lectin SIGLEC7 on the cell surface
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Tetsuya Okajima, Noboru Hashimoto, Keiko Furukawa, Yuhsuke Ohmi, Robiul H. Bhuiyan, Akihito Yamamoto, Koichi Furukawa, Akiko Tsuchida, and Shizuka Ito
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0301 basic medicine ,Ceramide ,Cell ,Glycobiology and Extracellular Matrices ,Antigens, Differentiation, Myelomonocytic ,Sialic acid binding ,Ceramides ,Biochemistry ,Glycosphingolipids ,Substrate Specificity ,Cell membrane ,03 medical and health sciences ,chemistry.chemical_compound ,Cell Line, Tumor ,Gangliosides ,Lectins ,medicine ,Humans ,Cytotoxicity ,Molecular Biology ,Ganglioside ,030102 biochemistry & molecular biology ,biology ,Chemistry ,Cell Membrane ,Cell Biology ,Sphingolipid ,N-Acetylneuraminic Acid ,Sialyltransferases ,030104 developmental biology ,medicine.anatomical_structure ,Leukocytes, Mononuclear ,biology.protein ,lipids (amino acids, peptides, and proteins) ,Antibody ,Protein Binding - Abstract
To analyze the binding specificity of a sialic acid–recognizing lectin, sialic acid-binding Ig-like lectin 7 (SIGLEC7), to disialyl gangliosides (GD3s), here we established GD3-expressing cells by introducing GD3 synthase (GD3S or ST8SIA1) cDNA into a colon cancer cell line, DLD-1, that expresses no ligands for the recombinant protein SIGLEC7-Fc. SIGLEC7-Fc did not recognize newly-expressed GD3 on DLD-1 cells, even though GD3 was highly expressed, as detected by an anti-GD3 antibody. Because milk-derived GD3 could be recognized by this fusion protein when incorporated onto the surface of DLD-1 cells, we compared the ceramides in DLD-1–generated and milk-derived GD3s to identify the SIGLEC7-specific GD3 structures on the cell membrane, revealing that SIGLEC7 recognizes only GD3-containing regular ceramides but not phytoceramides. This was confirmed by knockdown/knockout of the sphingolipid delta(4)-desaturase/C4-monooxygenase (DES2) gene, involved in phytoceramide synthesis, disclosing that DES2 inhibition confers SIGLEC7 binding. Furthermore, knocking out fatty acid 2-hydroxylase also resulted in the emergence of SIGLEC7 binding to the cell surface. To analyze the effects of binding between SIGLEC7 and various GD3 species on natural killer function, we investigated cytotoxicity of peripheral blood mononuclear cells from healthy donors toward GD3S-transfected DLD-1 (DLD-1–GD3S) cells and DLD-1–GD3S cells with modified ceramides. We found that cytotoxicity is suppressed in DLD-1–GD3S cells with dehydroxylated GD3s. These results indicate that the ceramide structures in glycosphingolipids affect SIGLEC7 binding and distribution on the cell surface and influence cell sensitivity to killing by SIGLEC7-expressing effector cells.
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- 2019
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31. Stromal cell-derived factor-1 accelerates bone regeneration through multiple regenerative mechanisms
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Jun Ishikawa, Masahito Fujio, Akihito Yamamoto, Hirotaka Wakayama, Yuji Ando, Yoshihiro Matsushita, and Hideharu Hibi
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biology ,business.industry ,Angiogenesis ,Mesenchymal stem cell ,Cell migration ,030206 dentistry ,Pathology and Forensic Medicine ,Cell biology ,Transplantation ,03 medical and health sciences ,0302 clinical medicine ,Otorhinolaryngology ,030220 oncology & carcinogenesis ,biology.protein ,Medicine ,Surgery ,Stromal cell-derived factor 1 ,Oral Surgery ,Progenitor cell ,Stem cell ,business ,Bone regeneration - Abstract
Objective Stem cell transplantation has become a popular and promising therapeutic approach for many clinical conditions. Engrafted mesenchymal stem cells (MSCs) can promote bone regeneration in both humans and model animals; however, the differentiation and survival rates of the engrafted MSCs are reported to be poor. We hypothesized that MSCs promote bone regeneration primarily through paracrine mechanisms. SDF-1 is a factor secreted from MSCs that is known to be involved in cell-recruitment and angiogenesis. In this study, we examined the bone-regenerating activity of SDF-1 in the rat calvarial bone defect model. Methods Collagen sponge containing SDF-1 was transplanted into the rat calvarial bone defect. The effects of treatment were examined both histological and microcomputed tomography analysis. The effects of SDF-1 on cellular migration and proliferationin vitro were assessed by transwell and WST-assay, respectively. Results SDF-1 significantly enhanced the bone regeneration in rat calvarial bone defect model. SDF-1 promoted the recruitment of endogenous MSCs/osteogenic progenitors and promoted angiogenesisin vivo. Furthermore, SDF-1 directly enhanced the cell-migration activity of human bone marrow MSCs (hBMMSCs), human umbilical vein endothelial cells (HUVECs), and rat calvarial periosteum cells (rCPCs), without affecting their proliferative activities, in vitro. Conclusions Our findings suggest that the local administration of SDF-1 enhances bone regeneration by inducing multiple endogenous tissue-regenerating activities.
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- 2019
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32. Monocyte chemoattractant protein-1 and secreted ectodomain of sialic acid-binding Ig-like lectin-9 enhance bone regeneration by inducing M2 macrophages
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Jun Ishikawa, Yuji Ando, Akihito Yamamoto, Hideharu Hibi, and Fumiya Kano
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business.industry ,Monocyte ,030206 dentistry ,Bone healing ,Sialic Acid-Binding Ig-Like Lectin 9 ,M2 Macrophage ,Bone morphogenetic protein 2 ,Pathology and Forensic Medicine ,Cell biology ,03 medical and health sciences ,0302 clinical medicine ,medicine.anatomical_structure ,Immune system ,Otorhinolaryngology ,Ectodomain ,030220 oncology & carcinogenesis ,medicine ,Surgery ,Oral Surgery ,business ,Bone regeneration - Abstract
Objective The bone-healing process consists of a primary inflammatory phase and a subsequent anti-inflammatory bone-forming phase. It was recently suggested that macrophages play an indispensable role in bone healing. Macrophages are plastic immune cells consisting of several subtypes, including pro-inflammatory M1-type and anti-inflammatory M2-type macrophages. Recently, a set of M2 macrophage inducers was described, monocyte chemoattractant protein-1 (MCP-1) and the secreted ectodomain of sialic acid-binding Ig-like lectin-9 (sSiglec-9), and applied them to a rat spinal cord injury model. Here, we hypothesized that MCP-1/sSiglec-9 enhance bone regeneration by inducing M2 macrophages. Methods We investigated the osteogenic activity of MCP-1/sSiglec-9 in vitro and in the rat calvarial bone defect model. Results We found that MCP-1/sSiglec-9 induced M2 macrophagesin vitro, which expressed increased levels of multiple mRNAs that encode osteogenic factors, including Igf-1, Tgf-β, Hgf, Bmp2, and Fgf2. We then demonstrated that MCP-1/sSiglec-9 accelerated bone formation and caused anti-inflammatory M2 macrophages to accumulate in the rat calvarial bone defect in vivo. Conclusions Collectively, our data suggest that the local administration of MCP-1/sSiglec-9 promotes bone formation by inducing anti-inflammatory M2 macrophages that express a variety of osteogenic factors. MCP-1/sSiglec-9 may be beneficial in bone regenerative therapy.
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- 2019
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33. Successful surgical treatment of a giant uterine leiomyoma: A case report
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Akihito Yamamoto and Shunji Suzuki
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medicine.medical_specialty ,Uterine leiomyoma ,business.industry ,Deep vein ,Abdominal aorta ,Balloon catheter ,Myoma ,medicine.disease ,Inferior vena cava ,Thrombosis ,female genital diseases and pregnancy complications ,Surgery ,Leiomyoma ,medicine.anatomical_structure ,medicine.vein ,medicine.artery ,medicine ,business - Abstract
Introduction and importance Uterine leiomyoma is a common disease. The tumor gradually increases and becomes a target for treatment when accompanied by certain symptoms. It rarely grows into a giant uterine leiomyoma, which is defined as leiomyoma weighing >11.34 kg. Case presentation A 58-year-old Japanese woman had a history of putamen hemorrhage and deep vein thrombosis. A giant uterine leiomyoma prevented her from walking, and she scheduled surgery for its removal. The tumor was 46 × 35 × 27 cm, and the uterine arteries and veins were extremely dilated. A blocking balloon catheter was placed in the abdominal aorta to prevent massive bleeding, and a filter was placed in the inferior vena cava to prevent pulmonary thromboembolism. The surgery focused on careful vascular treatment, with selective ligation of the ovarian arteries and veins and the uterine arteries. The total amount of bleeding was 1130 g, and the uterus was removed without complications. The weight of the excised tissue was 22.6 kg. Clinical discussion Surgical treatment of the largest giant uterine leiomyomas is rare and challenging. Previous reports addressed the risk of massive bleeding and perioperative death. Surgery is the best treatment for giant uterine leiomyomas, but perioperative management and surgical procedures require complex and elaborate planning. Conclusion Very few gynecologists have experience treating giant uterine leiomyomas. Successful surgery requires careful surgical preparation, and the gynecological oncologist must have extensive experience with giant leiomyomas.
- Published
- 2021
34. Die Schwerter des Masamune: Perfektion in Stahl : Die Technik und das Erbe der berühmtesten Klingen Japans
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Akihito Yamamoto and Akihito Yamamoto
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Masamune, der legendäre Schwertschmied aus der Kamakura-Zeit, gilt als unübertroffener Meister der japanischen Schwertkunst. Seine Klingen, berühmt für ihre außergewöhnliche Schärfe und Schönheit, sind bis heute Symbole für höchste handwerkliche Präzision und spirituelle Bedeutung. Doch was machte seine Schwerter so einzigartig? Und wie gelang es ihm, Techniken zu entwickeln, die bis in die moderne Zeit bewundert werden? Akihito Yamamoto entführt Sie in die faszinierende Welt von Masamune und seinen unsterblichen Klingen. Mit tiefem Einblick in die historischen und technischen Aspekte der Schwertschmiedekunst zeigt er, wie Masamunes Arbeiten das Erbe der Samurai-Kultur prägten und über Jahrhunderte hinweg bewahrt wurden. Detaillierte Beschreibungen der Techniken, die Geheimnisse hinter dem mythischen'Hamon'-Muster und die Geschichten berühmter Klingen wie dem'Honjō Masamune'machen dieses Buch zu einem unverzichtbaren Werk für Kenner und Liebhaber japanischer Kultur und Handwerkskunst. Entdecken Sie das Leben und die Werke eines Mannes, dessen Kunst bis heute eine unvergängliche Faszination ausübt.
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- 2024
35. Conditioned medium from the stem cells of human exfoliated deciduous teeth ameliorates neuropathic pain in a partial sciatic nerve ligation model
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Fumiya Kano, Noboru Hashimoto, Tsutomu Iwamoto, Linze Xia, Hideharu Hibi, Yao Liu, Yoshizo Matsuka, Eiji Tanaka, and Akihito Yamamoto
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Pathology ,medicine.medical_specialty ,medicine.anatomical_structure ,business.industry ,Neuropathic pain ,Deciduous teeth ,medicine ,Conditioned medium ,Sciatic nerve ,Stem cell ,business ,Ligation - Abstract
BackgroundAlthough recent studies have revealed the powerful antinociceptive effect of human dental pulp stem cells in an animal model for diabetes and osteoarthritis, its analgesic mechanisms are still largely elusive. We have previously reported that conditioned medium (CM) from dental pulp stem cells of deciduous teeth (SHED-CM) or its components, monocyte chemoattractant protein-1 (MCP-1) and the secreted ectodomain of sialic acid-binding Ig-like lectin-9 (sSiglec-9), directly induces anti-inflammatory M2 macrophages, however the antinociceptive activity of induced M2 is unknown. In this study, we investigated the antinociceptive effect of SHED-CM, MCP-1, and sSiglec-9 or secretome from M2-induced by SHED-CM (M2-CM) against neuropathic pain (NP) using a partial sciatic nerve ligation (PSL) mouse model and analyzed the mechanical bases of their antinociceptive effects. MethodsPSL mice were treated using SHED-CM with or without mannosylated-Clodrosome, specifically depleting M2 macrophages, recombinant MCP-1 and sSiglec-9 protein, M2-CM, or fibroblast-CM. Human Schwann cells activated by TNF-α in vitro were treated with M2-CM. The expression of pro-inflammatory mediators, neuroprotective factors, the nociceptive receptor, and markers for M1, M2, and activated glial cells in injured sciatic nerve (SCN), dorsal root ganglion, or spinal cord were evaluated by RT-PCR and immunohistochemistry. Mechanical allodynia of PSL mice was analyzed via von Frey test. ResultsIn the behavioral test, intravenous administration of SHED-CM greatly improved the PSL-induced hypersensitivity. SHED-CM treatment recruited M2 macrophages in the injured SCN and ipsilateral L4/L5 dorsal root ganglion and suppressed microglial activation in the spinal cord. Specific depletion of the M2 by mannosylated-Clodrosome markedly reduced the antinociceptive effect of SHED-CM. Intravenous administration of both MCP-1/sSiglec-9 and M2-CM ameliorated the PSL-induced hypersensitivity. We found that M2-CM directly suppressed the expression of nociceptive receptors as well as proinflammatory mediators in Schwann cells. ConclusionTaken together, our data suggest that SHED-CM ameliorates NP through the induction of the analgesic anti-inflammatory M2 macrophages. Thus, SHED-CM may present as a potential novel therapeutic candidate for NP.
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- 2021
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36. Secreted Factors from Stem Cells of Human Exfoliated Deciduous Teeth Directly Activate Endothelial Cells to Promote All Processes of Angiogenesis
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Hideki Kamiya, Mikio Motegi, Hiromi Nakai-Shimoda, Tatsuhito Himeno, Saeko Asano, Nobuhisa Nakamura, Jiro Nakamura, Yoshiaki Morishita, Shin Tsunekawa, Sachiko Sasajima, Keiko Naruse, Akihito Yamamoto, Takako Izumoto-Akita, Makoto Kato, Tomohide Hayami, Emi Asano-Hayami, Emiri Miura-Yura, Yusuke Hayashi, Yuichiro Yamada, Yoshiro Kato, and Masaki Kondo
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Male ,Angiogenesis ,SHED ,Cell Separation ,Tooth Exfoliation ,Article ,Neovascularization ,Paracrine signalling ,Mice ,angiogenesis ,Cell Movement ,medicine ,Human Umbilical Vein Endothelial Cells ,Animals ,Humans ,Viability assay ,Therapeutic angiogenesis ,Tooth, Deciduous ,Child ,lcsh:QH301-705.5 ,Cells, Cultured ,Chemistry ,Stem Cells ,General Medicine ,Rats ,Endothelial stem cell ,Mice, Inbred C57BL ,conditioned medium ,lcsh:Biology (General) ,Culture Media, Conditioned ,Cancer research ,endothelial cell ,Angiogenesis Inducing Agents ,Stem cell ,medicine.symptom ,Wound healing - Abstract
Diabetes is a major risk factor for atherosclerosis and ischemic vascular diseases. Recently, regenerative medicine is expected to be a novel therapy for ischemic diseases. Our previous studies have reported that transplantation of stem cells promoted therapeutic angiogenesis for diabetic neuropathy and ischemic vascular disease in a paracrine manner, but the precise mechanism is unclear. Therefore, we examined whether secreted factors from stem cells had direct beneficial effects on endothelial cells to promote angiogenesis. The soluble factors were collected as conditioned medium (CM) 48 h after culturing stem cells from human exfoliated deciduous teeth (SHED) in serum-free DMEM. SHED-CM significantly increased cell viability of human umbilical vein endothelial cells (HUVECs) in MTT assays and accelerated HUVECs migration in wound healing and Boyden chamber assays. In a Matrigel plug assay of mice, the migrated number of primary endothelial cells was markedly increased in the plug containing SHED-CM or SHED suspension. SHED-CM induced complex tubular structures of HUVECs in a tube formation assay. Furthermore, SHED-CM significantly increased neovascularization from the primary rat aorta, indicating that SHED-CM stimulated primary endothelial cells to promote comprehensive angiogenesis processes. The angiogenic effects of SHED-CM were the same or greater than the effective concentration of VEGF. In conclusion, SHED-CM directly stimulates vascular endothelial cells to promote angiogenesis and is promising for future clinical application.
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- 2020
37. Secreted Ectodomain of Sialic Acid-Binding Ig-Like Lectin-9 and Monocyte Chemoattractant Protein-1 Synergistically Regenerate Transected Rat Peripheral Nerves by Altering Macrophage Polarity
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Akihito Yamamoto, Kohki Matsubara, Hideharu Hibi, Fumiya Kano, and Minoru Ueda
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0301 basic medicine ,Cellular differentiation ,Neuronal Outgrowth ,Nerve fiber ,Biology ,Rats, Sprague-Dawley ,03 medical and health sciences ,Cell Movement ,Ganglia, Spinal ,medicine ,Animals ,Humans ,Macrophage ,Peripheral Nerves ,Tooth, Deciduous ,Child ,Chemokine CCL2 ,Cell Proliferation ,Inflammation ,Sialic Acid Binding Immunoglobulin-like Lectins ,Macrophages ,Stem Cells ,Monocyte ,Cell Polarity ,Cell Differentiation ,Recovery of Function ,Cell Biology ,M2 Macrophage ,Nerve Regeneration ,Cell biology ,Facial Nerve ,030104 developmental biology ,medicine.anatomical_structure ,Ectodomain ,Immunology ,Peripheral nerve injury ,Molecular Medicine ,Female ,Schwann Cells ,Stem cell ,Signal Transduction ,Developmental Biology - Abstract
Peripheral nerves (PNs) exhibit remarkable self-repairing reparative activity after a simple crush or cut injury. However, the neuronal transection involving a nerve gap overwhelms their repairing activity and causes persistent paralysis. Here, we show that an implantation of the serum-free conditioned medium from stem cells from human exfoliated deciduous teeth (SHED-CM) immersed in a collagen sponge into the nerve gap formed by rat facial nerves transection restored the neurological function. In contrast, SHED-CM specifically depleted of a set of anti-inflammatory M2 macrophage inducers, monocyte chemoattractant protein-1 (MCP-1) and the secreted ectodomain of sialic acid-binding Ig-like lectin-9 (sSiglec-9) lost the ability to restore neurological function in this model. Notably, the combination of MCP-1 and sSiglec-9 induced the polarization of M2 macrophages in vitro, resulting in the expression of multiple trophic factors that enhanced proliferation, migration, and differentiation of Schwann cells, blood vessel formation, and nerve fiber extension. Furthermore, the implantation of a collagen graft containing MCP-1/sSiglec-9 into the nerve gap induced anti-inflammatory M2 macrophage polarization, generated a Schwann-cell bridge instead of fibrotic scar, induced axonal regrowth, and restored nerve function. The specific elimination of M2 macrophages by Mannosylated-Clodrosome suppressed the MCP-1/sSiglec-9-mediated neurological recovery. Taken together, our data suggest that MCP-1/sSiglec-9 regenerates PNs by inducing tissue-repairing M2 macrophages and may provide therapeutic benefits for severe peripheral nerve injuries.
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- 2016
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38. Multifaceted Therapeutic Benefits of Factors Derived From Dental Pulp Stem Cells for Mouse Liver Fibrosis
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Minoru Ueda, Akihito Yamamoto, Marina Hirata, Takanori Ito, Masatoshi Ishigami, Hisashi Hattori, Hidemi Goto, Hideharu Hibi, and Yoshihiro Matsushita
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Liver Cirrhosis ,0301 basic medicine ,Pathology ,medicine.medical_specialty ,Cirrhosis ,Inflammation ,Mesenchymal Stem Cell Transplantation ,Real-Time Polymerase Chain Reaction ,Proinflammatory cytokine ,Mice ,03 medical and health sciences ,Tissue Engineering and Regenerative Medicine ,Dental pulp stem cells ,medicine ,Animals ,Humans ,Carbon Tetrachloride ,Dental Pulp ,Hepatocyte Growth Factor ,business.industry ,Mesenchymal Stem Cells ,Cell Biology ,General Medicine ,medicine.disease ,Immunohistochemistry ,Mice, Inbred C57BL ,Disease Models, Animal ,030104 developmental biology ,Apoptosis ,Culture Media, Conditioned ,Cancer research ,Hepatic stellate cell ,Female ,Hepatocyte growth factor ,Stem cell ,medicine.symptom ,business ,Developmental Biology ,medicine.drug - Abstract
Chronic liver injury from various causes often results in liver fibrosis (LF). Although the liver possesses endogenous tissue-repairing activities, these can be overcome by sustained inflammation and excessive fibrotic scar formation. Advanced LF leads to irreversible cirrhosis and subsequent liver failure and/or hepatic cancer. Here, using the mouse carbon tetrachloride (CCl4)-induced LF model, we showed that a single intravenous administration of stem cells derived from human exfoliated deciduous teeth (SHEDs) or of SHED-derived serum-free conditioned medium (SHED-CM) resulted in fibrotic scar resolution. SHED-CM suppressed the gene expression of proinflammatory mediators, such as TNF-α, IL-1β, and iNOS, and eliminated activated hepatic stellate cells by inducing their apoptosis, but protected parenchymal hepatocytes from undergoing apoptosis. In addition, SHED-CM induced tissue-repairing macrophages that expressed high levels of the profibrinolytic factor, matrix metalloproteinase 13. Furthermore, SHED-CM suppressed the CCl4-induced apoptosis of primary cultured hepatocytes. SHED-CM contained a high level of hepatocyte growth factor (HGF). Notably, HGF-depleted SHED-CM (dHGF-CM) did not suppress the proinflammatory response or resolve fibrotic scarring. Furthermore, SHED-CM, but not dHGF-CM, inhibited CCl4-induced hepatocyte apoptosis. These results suggest that HGF plays a central role in the SHED-CM-mediated resolution of LF. Taken together, our findings suggest that SHED-CM provides multifaceted therapeutic benefits for the treatment of LF. Significance This study demonstrated that a single intravenous administration of stem cells from human exfoliated deciduous teeth (SHEDs) or of the serum-free conditioned medium (CM) derived from SHEDs markedly improved mouse liver fibrosis (LF). SHED-CM suppressed chronic inflammation, eliminated activated hepatic stellate cells by inducing their apoptosis, protected hepatocytes from undergoing apoptosis, and induced differentiation of tissue-repairing macrophages expressing high levels of the profibrinolytic factor matrix metalloproteinase 13. Furthermore, hepatocyte growth factor played a central role in the SHED-CM-mediated resolution of LF. This is the first report demonstrating the multifaceted therapeutic benefits of secreted factors derived from SHEDs for LF.
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- 2016
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39. Conditioned Medium from the Stem Cells of Human Exfoliated Deciduous Teeth Ameliorates Experimental Autoimmune Encephalomyelitis
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Chiaki Shimojima, Hideharu Hibi, Akihito Yamamoto, Minoru Ueda, Akio Suzumura, Hideyuki Takeuchi, Hisashi Hattori, Shijie Jin, and Bijay Parajuli
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CD4-Positive T-Lymphocytes ,0301 basic medicine ,Encephalomyelitis, Autoimmune, Experimental ,Multiple Sclerosis ,Encephalomyelitis ,Immunology ,Lymphocyte Activation ,Proinflammatory cytokine ,Myelin oligodendrocyte glycoprotein ,Mice ,03 medical and health sciences ,Myelin ,Antigens, CD ,Demyelinating disease ,medicine ,Animals ,Humans ,Immunology and Allergy ,Tooth, Deciduous ,Cells, Cultured ,Sialic Acid Binding Immunoglobulin-like Lectins ,biology ,Microglia ,Macrophages ,Experimental autoimmune encephalomyelitis ,Mesenchymal Stem Cells ,medicine.disease ,Peptide Fragments ,Mice, Inbred C57BL ,Disease Models, Animal ,030104 developmental biology ,medicine.anatomical_structure ,Culture Media, Conditioned ,biology.protein ,Cytokines ,Female ,Myelin-Oligodendrocyte Glycoprotein ,Stem cell - Abstract
Multiple sclerosis (MS) is a major neuroinflammatory demyelinating disease of the CNS. Current MS treatments, including immunomodulators and immunosuppressants, do not result in complete remission. Stem cells from human exfoliated deciduous teeth (SHEDs) are mesenchymal stem cells derived from dental pulp. Both SHED and SHED-conditioned medium (SHED-CM) exhibit immunomodulatory and regenerative activities and have the potential to treat various diseases. In this study, we investigated the efficacy of SHED-CM in treating experimental autoimmune encephalomyelitis (EAE), a mouse model of MS. EAE mice treated with a single injection of SHED-CM exhibited significantly improved disease scores, reduced demyelination and axonal injury, and reduced inflammatory cell infiltration and proinflammatory cytokine expression in the spinal cord, which was associated with a shift in the microglia/macrophage phenotype from M1 to M2. SHED-CM also inhibited the proliferation of myelin oligodendrocyte glycoprotein–specific CD4+ T cells, as well as their production of proinflammatory cytokines in vitro. Treatment of EAE mice with the secreted ectodomain of sialic acid–binding Ig-like lectin-9, a major component of SHED-CM, recapitulated the effects of SHED-CM treatment. Our data suggest that SHED-CM and secreted ectodomain of sialic acid–binding Ig-like lectin-9 may be novel therapeutic treatments for autoimmune diseases, such as MS.
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- 2016
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40. Study of Observer Considering Damper Force Dynamics for Semi Active Suspension Systems
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Akihito Yamamoto, Shunya Tanaka, Wataru Tanaka, Takafumi Makino, and Ken Tahara
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050210 logistics & transportation ,Semi active ,020303 mechanical engineering & transports ,0203 mechanical engineering ,Observer (quantum physics) ,Computer science ,Control theory ,0502 economics and business ,05 social sciences ,Force dynamics ,02 engineering and technology ,General Medicine ,Damper - Published
- 2016
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41. Conditioned media from hypoxic-cultured human dental pulp cells promotes bone healing during distraction osteogenesis
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Ying Xue, Inge Fristad, Masahito Fujio, Minoru Ueda, Kamal Mustafa, Niyaz Sharabi, Zhe Xing, Akihito Yamamoto, and Hideharu Hibi
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0301 basic medicine ,business.industry ,medicine.medical_treatment ,Biomedical Engineering ,Medicine (miscellaneous) ,Bone healing ,Hypoxia (medical) ,Regenerative medicine ,Umbilical vein ,Staining ,Biomaterials ,Andrology ,03 medical and health sciences ,030104 developmental biology ,Tissue engineering ,In vivo ,medicine ,Distraction osteogenesis ,medicine.symptom ,business ,Biomedical engineering - Abstract
Distraction osteogenesis (DO) is a surgical procedure used to correct various skeletal disorders. Improving the technique by reducing the healing time would be of clinical relevance. The aim of this study was to determine the angiogenic and regenerative potential of conditioned media (CMs) collected from human dental pulp cells (hDPCs) grown under different culture conditions. CM collected from cells under hypoxia was used to improve bone healing and the DO procedure in vivo. The angiogenic potentials of CMs collected from hDPCs grown under normoxic (-Nor) and hypoxic (-Hyp) conditions were evaluated by quantitative PCR (VEGF-A, angiopoietin-1, angiopoietin-2, interleukin-6 (IL-6) and CXCL12), ELISA assays (VEGF-A, Ang-2), tube-formation and wound-healing assays, using human umbilical vein endothelial cells. The results demonstrated that hypoxic CM had significantly higher angiogenic potential than normoxic CM. Human fetal osteoblasts (hFOBs) were exposed to CM, followed by alizarin red staining, to assess the osteogenic potential. It was found that CM did not enhance the mineralization capacity of hFOBs. DO was performed in the tibiae of 30 mice, followed by a local injection of 20 µl CM (CM-Nor and CM-Hyp groups) or serum-free DMEM (control group) into the distraction zone every second day. The mice were sacrificed at days 13 and 27. The CM-Hyp treatment revealed a higher X-ray density than the control group (p
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- 2015
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42. Multifaceted therapeutic benefits of factors derived from stem cells from human exfoliated deciduous teeth for acute liver failure in rats
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Minoru Ueda, Hidemi Goto, Yoshihiro Matsushita, Hirotaka Wakayama, Masatoshi Ishigami, Kohki Matsubara, Megumi Kondo, and Akihito Yamamoto
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0301 basic medicine ,Pathology ,medicine.medical_specialty ,Innate immune system ,Angiogenesis ,business.industry ,Biomedical Engineering ,Medicine (miscellaneous) ,Inflammation ,Sudden death ,Liver regeneration ,Biomaterials ,03 medical and health sciences ,030104 developmental biology ,medicine.anatomical_structure ,Hepatocyte ,Cancer research ,Medicine ,Progenitor cell ,medicine.symptom ,Stem cell ,business - Abstract
In acute liver failure (ALF), a poorly controlled innate immune response causes massive hepatic destruction, which elicits a systemic inflammatory response, progressive multiple organ failure and ultimate sudden death. Although the liver has inherent tissue-repairing activities, its regeneration during ALF fails, and orthotopic liver transplantation is the only curative approach. Here we show that a single intravenous administration of stem cells derived from human exfoliated deciduous teeth (SHEDs) or of SHED-derived serum-free conditioned medium (SHED-CM) into the d-galactosamine-induced rat model of ALF markedly improved the condition of the injured liver and the animals' survival rate. The engraftment of infused SHEDs was very low, and both SHEDs and SHED-CM exerted similar levels of therapeutic effect, suggesting that the SHEDs reversed ALF by paracrine mechanisms. Importantly, SHED-CM attenuated the ALF-induced pro-inflammatory response and generated an anti-inflammatory/tissue-regenerating environment, which was accompanied by the induction of anti-inflammatory M2-like hepatic macrophages. Secretome analysis by cytokine antibody array revealed that the SHED-CM contained multiple tissue-regenerating factors with known roles in anti-apoptosis/hepatocyte protection, angiogenesis, macrophage differentiation and the proliferation/differentiation of liver progenitor cells. Taken together, our findings suggest that SHEDs produce factors that provide multifaceted therapeutic benefits for AFL. Copyright © 2015 John Wiley & Sons, Ltd.
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- 2015
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43. Dopaminergic differentiation of stem cells from human deciduous teeth and their therapeutic benefits for Parkinsonian rats
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Kinji Ohno, Kiyoshi Sakai, Hiromi Fujii, Akihito Yamamoto, Minoru Ueda, Kohki Matsubara, and Mikako Ito
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Neurite ,Cell Survival ,Nerve Tissue Proteins ,Neuroprotection ,Paracrine signalling ,Neural Stem Cells ,Neurotrophic factors ,Basic Helix-Loop-Helix Transcription Factors ,Glial cell line-derived neurotrophic factor ,medicine ,Animals ,Humans ,Tooth, Deciduous ,Child ,Molecular Biology ,Epidermal Growth Factor ,biology ,Brain-Derived Neurotrophic Factor ,Dopaminergic Neurons ,General Neuroscience ,Neurodegeneration ,Dopaminergic ,Cell Differentiation ,Parkinson Disease ,medicine.disease ,Rats ,Cell biology ,nervous system ,biology.protein ,Fibroblast Growth Factor 2 ,Neurology (clinical) ,Stem cell ,Neuroscience ,Developmental Biology - Abstract
Parkinson's disease (PD) is a progressive neurodegenerative disorder caused by the loss of nigrostriatal dopaminergic (DAergic) neurons and the depletion of striatal dopamine. Here we show that DAergic-neuron-like cells could be efficiently induced from stem cells derived from human exfoliated deciduous teeth (SHEDs), and that these induced cells had therapeutic benefits in a 6-OHDA-induced Parkinsonian rat model. In our protocol, EGF and bFGF signaling activated the SHED's expression of proneural genes, Ngn2 and Mash1, and subsequent treatment with brain-derived neurotrophic factor (BDNF) promoted their maturation into DAergic neuron-like SHEDs (dSHEDs). A hypoxic DAergic differentiation protocol improved cell viability and enhanced the expression of multiple neurotrophic factors, including BDNF, GDNF, NT-3, and HGF. Engrafted dSHEDs survived in the striatum of Parkinsonian rats, improved the DA level more efficiently than engrafted undifferentiated SHEDs, and promoted the recovery from neurological deficits. Our findings further suggested that paracrine effects of dSHEDs contributed to neuroprotection against 6-OHDA-induced neurodegeneration and to nigrostriatal tract restoration. In addition, we found that the conditioned medium derived from dSHEDs protected primary neurons against 6-OHDA toxicity and accelerated neurite outgrowth in vitro. Thus, our data suggest that stem cells derived from dental pulp may have therapeutic benefits for PD.
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- 2015
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44. Reinforced Degradable Biocomposite by Homogenously Distributed Functionalized Nanodiamond Particles
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Anke Krueger, Akihito Yamamoto, Mohamed A. Yassin, Kamal Mustafa, Doris Steinmüller-Nethl, Ann-Christine Albertsson, Zhe Xing, Yang Sun, Thilo Waag, and Anna Finne-Wistrand
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chemistry.chemical_classification ,Scaffold ,Materials science ,Polymers and Plastics ,General Chemical Engineering ,Organic Chemistry ,02 engineering and technology ,Polymer ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,Contact angle ,Tissue engineering ,chemistry ,Chemical engineering ,Materials Chemistry ,Fiber ,Composite material ,Biocomposite ,0210 nano-technology ,Nanodiamond ,Bone regeneration - Abstract
The treatment of bone defects is facing the situation of lacking donations for autotransplantation. As a valid approach, scaffold-based tissue engineering combines the construction of well-defined porous scaffolds with advanced cell culturing technology to guide tissue regeneration. The role for the scaffold is to provide a suitable environment with a sufficient mechanical stiffness, supports for cell attachment, migration, nutrients and metabolite transport and space for cell remodeling and tissue regeneration. The random copolymers poly(L-lactide-co-ɛ-caprolactone) (poly(LLA-co-CL)) and poly(L-lactide-co-1,5-dioxepan-2-one) (poly(LLA-co-DXO)) have been successfully incorporated into 3D porous scaffolds to induce specific interactions with cells and direct osteogenic cell differentiation. In this thesis, these scaffolds have been modified in chemical and physical ways to map and understand requirements for bone regeneration. Scaffold functionalities and properties, such as hydrophilicity, stiffness, size/shape, and reproducibility, were studied. The hydrophilicity was varied by adding 3–20 % (w/w) Tween 80 to poly(LLA-co-CL) and poly(LLA-co-DXO) respectively, which resulted in contact angles from 35° to 15°. With 3 % Tween 80, the resultant mechanical and thermal properties were similar to pristine polymer materials. Tween 80 did not significantly influence cell attachment or proliferation but did stimulate the mRNA expression of osteogenetic markers. The surface functionality and mechanical properties were altered by introducing nanodiamond particles (n-DP) into poly(LLA-co-CL) scaffolds by means of surface physisorption or hybrid blending. Scaffold with n-DP physisorbed showed improved cell attachment, differentiation, and bone reformation. Hybrid n-DP/poly(LLA-co-CL) composites were obtained by direct blending of polylactide modified n-DP (n-DP-PLA) with poly(LLA-coCL). The n-DP-PLA was prepared by sodium hydride-mediated anionic polymerization using n-DP as the initiator. Prepared n-DP-PLA could be dispersed homogenously in organic solvents and blended with poly(LLA-coCL) solution. The n-DP-PLA particles were homogenously distributed in the composite material, which significantly improved mechanical properties. For comparison, the addition of benzoquinone-modified n-DP (n-DP-BQ) did not reinforce poly(LLA-co-CL). This indicated the importance of specific surface grafting, which determined different particle-polymer interactions. For the treatment of critical size defects, a large porous poly(LLA-co-CL) scaffold (12.5 mm diameter × 25 mm thickness) was developed and produced by molding and salt-leaching methods. The large porous scaffolds were evaluated in a scaffold-customized perfusion-based bioreactor system. It was obvious that the scaffold could support improved cell distribution and support the stimulation of human mesenchymal stem cell (hMSC) especially with dynamic flow in a bioreactor. To improve the scaffolding technique, a three-dimensional fiber deposition (3DF) technique was employed to build layer-based scaffolds. Poly(LLA-coCL) scaffolds produced by the 3DF method showed enhanced mechanical properties and a homogeneous distribution of human osteoblasts (hOBs) in the scaffolds. Although poly(LLA-co-CL) was thermally degraded, the degradation did not influence the scaffold mechanical properties. Based on the computerized design, a 3DF scaffold of amorphous copolymer poly(LLAco-CL) provides high-precision control and reproducibility. In summary, the design of porous scaffolds is one of the essential factors in tissue engineering as to mimicking the intrinsic extracellular environment. For bone tissue engineering, an optimized scaffold can maintain a contact angle greater than 35 degrees. Pristine or modified n-DP, introduced as an additive by surface physisorption or direct blending, can improve scaffold mechanical properties and cell response. Various sizes of scaffolds can be easily produced by a mold-mediated salt-leaching method. However, when 100 % reproducibility is required, the 3DF method can be used to create customizable scaffolds.
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- 2015
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45. Serum CA 125 Level after Neoadjuvant Chemotherapy is Predictive of Prognosis and Debulking Surgery Outcomes in Advanced Epithelial Ovarian Cancer
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Hisamori Kato, Tomohiko Matsuhashi, Daisuke Doi, Takashi Yamada, Toshiyuki Takeshita, Ryo Onose, Keisuke Kurose, Akihito Yamamoto, Katsuyuki Konnai, and Rieko Kawase
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Oncology ,Adult ,medicine.medical_specialty ,medicine.medical_treatment ,Ovariectomy ,Disease-Free Survival ,03 medical and health sciences ,0302 clinical medicine ,Predictive Value of Tests ,Internal medicine ,medicine ,Biomarkers, Tumor ,Humans ,030212 general & internal medicine ,Stage (cooking) ,Neoadjuvant therapy ,Aged ,Neoplasm Staging ,Retrospective Studies ,Ovarian Neoplasms ,Chemotherapy ,business.industry ,Cancer ,Membrane Proteins ,Retrospective cohort study ,General Medicine ,Middle Aged ,Debulking ,medicine.disease ,Prognosis ,Neoadjuvant Therapy ,Treatment Outcome ,Chemotherapy, Adjuvant ,030220 oncology & carcinogenesis ,Predictive value of tests ,CA-125 Antigen ,Female ,business ,Ovarian cancer - Abstract
Recently, neoadjuvant chemotherapy followed by interval debulking surgery (NACT-IDS) has been recommended for selected patients with International Federation of Gynecology and Obstetrics (FIGO) stage III or IV disease and bulky tumors. The aim of this study was to evaluate associations between post-NACT serum CA 125 levels, surgical outcomes, and clinical outcomes in patients with advanced epithelial ovarian cancer. We retrospectively analyzed 107 patients with FIGO stage III or IV ovarian cancer who were treated with NACT-IDS at the Gynecology Department of Kanagawa Cancer Center between January 2001 and December 2012. Serum CA 125 levels after NACT were significantly lower in the complete/optimal IDS group compared to the suboptimal IDS group (mean±standard deviation: 48.1±27.6 vs. 346.5±295.2 U/mL, p0.01). Patients with low preoperative CA 125 levels (35 U/mL) had a higher probability of optimal IDS (78.1±41.9% vs. 33.3±19.2%, p0.01) and longer progression-free survival (mean±standard deviation: 30.4±14.3 months vs. 21.3±7.3 months, p0.05) than patients with high CA 125 levels (100 U/mL). Patients with low CA 125 levels (35 U/mL) had a higher probability of complete/optimal IDS and longer progression-free survival compared to patients with high CA 125 levels (100 U/mL).
- Published
- 2017
46. Accuracy Improvement of Character Recognition by Hexagonal Zoning
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Fumitaka Kimura, Wataru Ohyama, Tetsushi Wakabayashi, and Akihito Yamamoto
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Engineering drawing ,Hexagonal crystal system ,Computer science ,Electrical and Electronic Engineering ,Accuracy improvement ,Zoning ,Character recognition - Published
- 2014
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47. Secreted Ectodomain of SIGLEC-9 and MCP-1 Synergistically Improve Acute Liver Failure in Rats by Altering Macrophage Polarity
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Akihito Yamamoto, Kohki Matsubara, Tetsuya Ishikawa, Hidemi Goto, Hideharu Hibi, Masatoshi Ishigami, Minoru Ueda, Yoshihiro Matsushita, Marina Hirata, Yoshiki Hirooka, and Takanori Ito
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0301 basic medicine ,Apoptosis ,Tooth Exfoliation ,Culture Media, Serum-Free ,Article ,Rats, Sprague-Dawley ,03 medical and health sciences ,medicine ,Animals ,Macrophage ,Tooth, Deciduous ,Chemokine CCL2 ,Cell Proliferation ,Inflammation ,Sialic Acid Binding Immunoglobulin-like Lectins ,Liver injury ,Multidisciplinary ,Chemistry ,Macrophages ,Stem Cells ,SIGLEC ,Liver Failure, Acute ,M2 Macrophage ,medicine.disease ,Liver regeneration ,Cell biology ,030104 developmental biology ,medicine.anatomical_structure ,Ectodomain ,Hepatocyte ,Female - Abstract
Effective treatments for acute liver failure (ALF) are still lacking. We recently reported that a single intravenous administration of serum-free conditioned medium from stem cells derived from human exfoliated deciduous teeth (SHED-CM) into the D-galactosamine (D-Gal)-induced rat ALF model improves the liver injury. However, the specific factors in SHED-CM that are responsible for resolving ALF remain unclear. Here we found that depleting SHED-CM of two anti-inflammatory M2 macrophage inducers—monocyte chemoattractant protein-1 (MCP-1) and the secreted ectodomain of sialic acid-binding Ig-like lectin-9 (sSiglec-9)—abolished its ability to resolve rat ALF. Furthermore, treatment with MCP-1/sSiglec-9 alone dramatically improved the survival of ALF rats. This treatment induced anti-inflammatory M2, suppressed hepatocyte apoptosis, and promoted hepatocyte proliferation. Treatment with an M2-depletion reagent (mannosylated clodronate liposomes) suppressed the recovery. In addition, MCP-1 and sSiglec-9 synergistically promoted the M2 differentiation of bone marrow-derived macrophages via CCR2, accompanied by the production of multiple liver-regenerating factors. The conditioned medium from MCP-1/sSiglec-9-activated M2 macrophages, but not from interleukin-4-induced ones, suppressed the D-Gal- and LPS-induced apoptosis of primary hepatocytes and promoted their proliferation in vitro. The unique combination of MCP-1/sSiglec-9 ameliorates rat ALF by inhibiting hepatocellular apoptosis and promoting liver regeneration through the induction of anti-inflammatory/tissue-repairing M2 macrophages.
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- 2017
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48. Human Dental Pulp-Derived Stem Cells Protect Against Hypoxic-Ischemic Brain Injury in Neonatal Mice
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Kiyoshi Sakai, Mari Yamagata, Kohki Matsubara, Kazunobu Sawamoto, Eisuke Kako, Akihito Yamamoto, Minoru Ueda, and Naoko Kaneko
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Pathology ,medicine.medical_specialty ,Inflammation ,Neuroprotection ,Proinflammatory cytokine ,Mice ,Paracrine signalling ,Animals ,Humans ,Medicine ,Cells, Cultured ,Dental Pulp ,Advanced and Specialized Nursing ,business.industry ,Pathophysiology ,Transplantation ,Animals, Newborn ,Apoptosis ,Brain Injuries ,Hypoxia-Ischemia, Brain ,Neurology (clinical) ,Stem cell ,medicine.symptom ,Cardiology and Cardiovascular Medicine ,business ,Stem Cell Transplantation - Abstract
Background and Purpose— Perinatal hypoxia-ischemia (HI) has high rates of neurological deficits and mortality. So far, no effective treatment for HI brain injury has been developed. In this study, we investigated the therapeutic effects of stem cells from human exfoliated deciduous teeth (SHED) for the treatment of neonatal HI brain injury. Methods— Unilateral HI was induced in postnatal day 5 (P5) mice. Twenty-four hours later, SHED, human skin fibroblasts, or serum-free conditioned medium derived from these cells was injected into the injured brain. The effects of cell transplantation or conditioned medium injection on the animals’ neurological and pathophysiological recovery were evaluated. Results— Transplanted SHED, but not fibroblasts, significantly reduced the HI-induced brain-tissue loss and improved neurological function. SHED also improved the survival of the HI mice. The engrafted SHED rarely differentiated into neural lineages; however, their transplantation inhibited the expression of proinflammatory cytokines, increased the expression of anti-inflammatory ones, and significantly reduced apoptosis. Notably, the intracerebral administration of SHED-conditioned medium also significantly improved the neurological outcome, inhibited apoptosis, and reduced tissue loss. Conclusions— SHED transplantation into the HI-injured brain resulted in remarkable neurological and pathophysiological recovery. Our findings indicate that paracrine factors derived from SHED support a neuroprotective microenvironment in the HI brain. SHED graft and SHED-conditioned medium may provide a novel neuroprotective therapy for HI.
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- 2013
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49. Human umbilical cord-derived mesenchymal stromal cells promote sensory recovery in a spinal cord injury rat model
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Sachiko Takikawa, Akira Iwase, Kiyoshi Sakai, Ryutaro Shohara, Akihito Yamamoto, Fumitaka Kikkawa, and Minoru Ueda
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Pathology ,medicine.medical_specialty ,business.industry ,Mesenchymal stem cell ,Chronic pain ,medicine.disease ,Spinal cord ,Umbilical cord ,medicine.anatomical_structure ,Anesthesia ,Neuropathic pain ,medicine ,Paralysis ,Immunohistochemistry ,medicine.symptom ,business ,Spinal cord injury - Abstract
While paralysis is widely appreciated to impact the quality-of-life after spinal cord injuries (SCIs), neuropathic chronic pain may also occur in many cases. In this study, we investigated whether human umbilical cord-derived mesenchymal stromal cells (hUCMSCs) possess the therapeutic potential to reduce neuropathic pain following SCI in rats. Spinal cord hemitransection, which was used as a rat SCI pain model, induced tactile hypersensitivity in the hind paw and hyperexcitability of wild dynamic range neurons in response to natural cutaneous stimuli. Following hemitransection, we transplanted hUCMSCs into the spinal cord. Attenuation of neuronal hyperexcitability was observed in the hUCMSC-treated group compared with that observed in the vehicle-treated group. Immunohistochemistry showed that the transplanted hUCMSCs retained the expression of gammaamino butyric acid (GABA). The results suggest that transplanted hUCMSCs ameliorate GABAergic inhibition in the spinal cord. In summary, the production of GABA plays a critical role in the plasticity of neuropathic pain after implantation of hUCMSCs.
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- 2013
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50. Role of Protein Phosphatase 2A in Osteoblast Differentiation and Function
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Akihito Yamamoto, Kaya Yoshida, Hirohiko Okamura, Jumpei Teramachi, Kazuhiko Ochiai, Tatsuji Haneji, and Hiroyuki Morimoto
- Subjects
0301 basic medicine ,Phosphatase ,lcsh:Medicine ,macromolecular substances ,Review ,environment and public health ,adipogenesis ,03 medical and health sciences ,medicine ,Protein phosphorylation ,osteoclastogenesis ,bone formation ,business.industry ,Kinase ,Mesenchymal stem cell ,lcsh:R ,protein phosphatase ,Osteoblast ,General Medicine ,Protein phosphatase 2 ,osteosarcoma cells ,Cell biology ,enzymes and coenzymes (carbohydrates) ,030104 developmental biology ,medicine.anatomical_structure ,Biochemistry ,Adipogenesis ,osteoblast differentiation ,Phosphorylation ,business - Abstract
The reversible phosphorylation of proteins plays hugely important roles in a variety of cellular processes, such as differentiation, proliferation, and apoptosis. These processes are strictly controlled by protein kinases (phosphorylation) and phosphatases (de-phosphorylation). Here we provide a brief history of the study of protein phosphorylation, including a summary of different types of protein kinases and phosphatases. One of the most physiologically important serine/threonine phosphatases is PP2A. This review provides a description of the phenotypes of various PP2A transgenic mice and further focuses on the known functions of PP2A in bone formation, including its role in osteoblast differentiation and function. A reduction in PP2A promotes bone formation and osteoblast differentiation through the regulation of bone-related transcription factors such as Osterix. Interestingly, downregulation of PP2A also stimulates adipocyte differentiation from undifferentiated mesenchymal cells under the appropriate adipogenic differentiation conditions. In osteoblasts, PP2A is also involved in the ability to control osteoclastogenesis as well as in the proliferation and metastasis of osteosarcoma cells. Thus, PP2A is considered to be a comprehensive factor in controlling the differentiation and function of cells derived from mesenchymal cells such as osteoblasts and adipocytes.
- Published
- 2016
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