80 results on '"Kobayashi, Naoya"'
Search Results
2. Safety and outcome of three‐dimensional transoral videolaryngoscopic surgery.
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Ebisumoto, Koji, Sakai, Akihiro, Iijima, Hiroaki, Maki, Daisuke, Yamauchi, Mayu, Saito, Kosuke, Kaneda, Shoji, Teramura, Takanobu, Watanabe, Takane, Inagi, Toshihide, Yanagiya, Ryoko, Yamazaki, Aritomo, Ashida, Hiroshi, Ota, Yoshiyuki, Sato, Yurina, Yamamoto, Ai, Kobayashi, Naoya, and Okami, Kenji
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PHARYNGEAL cancer ,OROPHARYNGEAL cancer ,DEPTH perception ,STEREOSCOPIC views ,ENDOSCOPIC surgery ,NECK dissection - Abstract
Background: Transoral videolaryngoscopic surgery (TOVS) is widely used in Japan, and conventional two‐dimensional (2D) endoscopic methods have been established. Three‐dimensional (3D) endoscopic surgery offers superior distance perception because it provides stereoscopic views. Recently, we have developed 3D endoscopy for TOVS (3D TOVS). Methods: This study included 46 patients with pharyngeal cancer who underwent 3D TOVS. The perioperative complications and survival curves were retrospectively analyzed. Results: One patient with oropharyngeal cancer who underwent neck dissection and transoral resection simultaneously experienced postoperative hemorrhage of the neck. Another patient with oropharyngeal cancer underwent hemostasis for postoperative pharyngeal hemorrhage. There was one case of aspiration pneumonia. One patient developed cervical lymph node recurrence; however, there was no local recurrence or primary mortality. The 2‐year overall survival, disease‐specific survival, local control rates, locoregional control rate, and invasive disease‐free survival were 90.9%, 100%, 100%, 97.4%, and 79.9%, respectively. Conclusions: Three‐dimensional endoscopy can be safely applied to TOVS. [ABSTRACT FROM AUTHOR]
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- 2024
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3. FUCA1 : An Underexplored p53 Target Gene Linking Glycosylation and Cancer Progression.
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Hu, Die, Kobayashi, Naoya, and Ohki, Rieko
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ENZYME metabolism ,GLYCOSYLATION ,PROTEIN kinases ,GLYCOLYSIS ,PHOSPHORYLATION ,EPITHELIAL-mesenchymal transition ,DRUG resistance in cancer cells ,CELL physiology ,CELL proliferation ,TUMOR markers ,CELLULAR signal transduction ,CELL motility ,POLYSACCHARIDES ,ENERGY metabolism ,METASTASIS ,ONCOGENES ,METABOLISM ,TUMORS ,STEM cells ,DISEASE progression ,EPIDERMAL growth factor receptors - Abstract
Simple Summary: Cancer is a difficult-to-cure disease with high worldwide incidence and mortality. Among the many changes observed in cancer cells and patient samples is altered glycosylation, a commonly observed modification of biomolecules such as proteins. These glycan structures can dictate protein function, and dysregulation of glycosylation can contribute to tumor migration and metastasis. Thus, manipulation of glycosylation states may be a novel approach to cancer treatment. One target of the well-known tumor suppressor p53 is FUCA1, encoding alpha-L-fucosidase, which plays a role in glycosylation, although the exact mechanism linking FUCA1 to cancer is unclear. Investigation into these glycosylation processes and the mechanisms linking the p53-FUCA1 axis to cancer development may provide new insights into this disease and suggest new drug targets for cancer therapies. Cancer is a difficult-to-cure disease with high worldwide incidence and mortality, in large part due to drug resistance and disease relapse. Glycosylation, which is a common modification of cellular biomolecules, was discovered decades ago and has been of interest in cancer research due to its ability to influence cellular function and to promote carcinogenesis. A variety of glycosylation types and structures regulate the function of biomolecules and are potential targets for investigating and treating cancer. The link between glycosylation and carcinogenesis has been more recently revealed by the role of p53 in energy metabolism, including the p53 target gene alpha-L-fucosidase 1 (FUCA1), which plays an essential role in fucosylation. In this review, we summarize roles of glycan structures and glycosylation-related enzymes to cancer development. The interplay between glycosylation and tumor microenvironmental factors is also discussed, together with involvement of glycosylation in well-characterized cancer-promoting mechanisms, such as the epidermal growth factor receptor (EGFR), phosphatidylinositol-3-kinase/protein kinase B (PI3K/Akt) and p53-mediated pathways. Glycan structures also modulate cell–matrix interactions, cell–cell adhesion as well as cell migration and settlement, dysfunction of which can contribute to cancer. Thus, further investigation of the mechanistic relationships among glycosylation, related enzymes and cancer progression may provide insights into potential novel cancer treatments. [ABSTRACT FROM AUTHOR]
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- 2024
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4. Continuous visualization and validation of pain in critically ill patients using artificial intelligence: a retrospective observational study.
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Kobayashi, Naoya, Watanabe, Kazuki, Murakami, Hitoshi, and Yamauchi, Masanori
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ARTIFICIAL intelligence ,RECEIVER operating characteristic curves ,SIMULATED patients ,CRITICALLY ill ,INTENSIVE care patients - Abstract
Machine learning tools have demonstrated viability in visualizing pain accurately using vital sign data; however, it remains uncertain whether incorporating individual patient baselines could enhance accuracy. This study aimed to investigate improving the accuracy by incorporating deviations from baseline patient vital signs and the concurrence of the predicted artificial intelligence values with the probability of critical care pain observation tool (CPOT) ≥ 3 after fentanyl administration. The study included adult patients in intensive care who underwent multiple pain-related assessments. We employed a random forest model, utilizing arterial pressure, heart rate, respiratory rate, gender, age, and Richmond Agitation–Sedation Scale score as explanatory variables. Pain was measured as the probability of CPOT scores of ≥ 3, and subsequently adjusted based on each patient's baseline. The study included 10,299 patients with 117,190 CPOT assessments. Of these, 3.3% had CPOT scores of ≥ 3. The random forest model demonstrated strong accuracy with an area under the receiver operating characteristic curve of 0.903. Patients treated with fentanyl were grouped based on CPOT score improvement. Those with ≥ 1-h of improvement after fentanyl administration had a significantly lower pain index (P = 0.020). Therefore, incorporating deviations from baseline patient vital signs improved the accuracy of pain visualization using machine learning techniques. [ABSTRACT FROM AUTHOR]
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- 2023
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5. Continuous visualization and validation of pain in critically ill patients using artificial intelligence: a retrospective observational study.
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Kobayashi, Naoya, Watanabe, Kazuki, Murakami, Hitoshi, and Yamauchi, Masanori
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ARTIFICIAL intelligence ,RECEIVER operating characteristic curves ,SIMULATED patients ,CRITICALLY ill ,INTENSIVE care patients - Abstract
Machine learning tools have demonstrated viability in visualizing pain accurately using vital sign data; however, it remains uncertain whether incorporating individual patient baselines could enhance accuracy. This study aimed to investigate improving the accuracy by incorporating deviations from baseline patient vital signs and the concurrence of the predicted artificial intelligence values with the probability of critical care pain observation tool (CPOT) ≥ 3 after fentanyl administration. The study included adult patients in intensive care who underwent multiple pain-related assessments. We employed a random forest model, utilizing arterial pressure, heart rate, respiratory rate, gender, age, and Richmond Agitation–Sedation Scale score as explanatory variables. Pain was measured as the probability of CPOT scores of ≥ 3, and subsequently adjusted based on each patient's baseline. The study included 10,299 patients with 117,190 CPOT assessments. Of these, 3.3% had CPOT scores of ≥ 3. The random forest model demonstrated strong accuracy with an area under the receiver operating characteristic curve of 0.903. Patients treated with fentanyl were grouped based on CPOT score improvement. Those with ≥ 1-h of improvement after fentanyl administration had a significantly lower pain index (P = 0.020). Therefore, incorporating deviations from baseline patient vital signs improved the accuracy of pain visualization using machine learning techniques. [ABSTRACT FROM AUTHOR]
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- 2023
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6. Investigation of Risk Factors for Postoperative Delirium after Transcatheter Aortic Valve Implantation: A Retrospective Study.
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Ogata, Yuko, Kobayashi, Naoya, and Yamauchi, Masanori
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PREOPERATIVE risk factors ,RECEIVER operating characteristic curves ,DELIRIUM ,MULTIPLE regression analysis ,AORTIC stenosis - Abstract
Transcatheter aortic valve implantation (TAVI) is an effective treatment for severe aortic stenosis (AS); however, postoperative delirium (POD) can worsen patient outcomes. This study aimed to examine the risk factors for POD after TAVI, including possible intervening factors. We included 87 patients (mean age: 83) who underwent TAVI between May 2014 and September 2018. POD was defined by the presence or absence of delirium on ICU admission, assessed using the Confusion Assessment Method for the ICU. Factors that showed significant differences in the univariate analysis were analyzed using a multiple logistic regression analysis. In total, 31 patients (36%) had POD after ICU admission, and 56 (64%) did not. The preoperative frailty score and aortic valve opening area (AVA) were significant risk factors for POD. The multivariate analysis also showed that both factors were independent risk factors for POD (area under the receiver operating characteristic curve: 0.805). There were no significant differences in the number of ICU days. However, postoperative hospitalization was significantly longer in the POD group (19 (17–31) days vs. 16 (13–22) days; p = 0.002). POD was associated with a narrow AVA and frailty; this suggests that frailty prevention interventions according to the AVA may be important. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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7. A case of strongly suspected Lynch syndrome with colorectal neuroendocrine carcinoma.
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Kobayashi, Naoya, Yoshida, Hiroshi, Kawaguchi, Shinya, Shiraso, Satoru, Nemoto, Noriko, Fujikawa, Nanako, Haji, Yoichi, Kono, Emiko, Kokubo, Shoji, Tsukuda, Kazuhiko, Asano, Shigeyuki, and Shinya, Fumiaki
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HEREDITARY nonpolyposis colorectal cancer ,NEUROENDOCRINE tumors ,COLORECTAL cancer ,COLON cancer ,SIGMOID colon ,RECTUM tumors - Abstract
Background: Neuroendocrine cell carcinomas (NEC) of the colon and rectum are uncommon, representing ~ 0.1% of all colorectal carcinomas. They are associated with a much worse prognosis compared to adenocarcinoma of the colon and rectum, as death occurs in approximately half of all patients within 1 year. Lynch syndrome (LS) is the most common cause of inherited colorectal cancer, accounting for 2–4% of newly diagnosed colorectal cancer cases. This case is extremely rare which was strongly suspected LS as the background, and NEC as the histological type of colorectal cancer. Case presentation: The patient was a 44-year-old man presenting with vomiting as the main complaint. He had undergone ileocecal resection for cecal cancer at age 29. The diagnosis was obstructive descending colorectal cancer, and colonoscopy revealed tumors in the rectum and sigmoid colon in addition. Due to multiple occurrences of colorectal cancer and its prevalence in the patient's family, LS was suspected. The operation which was a subtotal proctocolectomy was performed. Pathological analysis revealed complete curative resection and the descending colon cancer of the obstructed portion was at the most advanced pathological Stage IIIC in UICC TNM classification, and the tissue type was a NEC. The Ki-67 index was 70%. The results of the microsatellite instability (MSI) test showed high-frequency MSI. The BRAF V600E variant was negative. The immunoexpression of MLH1 was positive, MSH2 was negative, PMS2 was positive, and MSH6 was negative. Conclusions: Extended surgery is recommended for incipient colorectal cancer in LS cases in order to reliably reduce the risk of developing metachronous colorectal cancer. The survival outcome of surgery alone on digestive tract NECs, even locoregional lesions that are completely resection, is extremely poor. It is currently unclear if digestive tract NECs develop more readily in patients with LS. The accumulation of additional cases is necessary. [ABSTRACT FROM AUTHOR]
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- 2022
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8. Formation of alkali metal titanate nanocrystals using titanium alkoxide.
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Nishikiori, Hiromasa, Ebara, Hiroyoshi, Takayama, Hitoshi, Adachi, Shinnosuke, Kobayashi, Naoya, Hayashi, Fumitaka, and Teshima, Katsuya
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TITANATES ,LITHIUM titanate ,ALKALI metals ,ALKALI metal compounds ,TITANIUM ,METAL nanoparticles ,METALS at low temperatures ,NANOCRYSTALS - Abstract
Nanocrystalline powders of alkali metal titanates were prepared using titanium tetraisopropoxide and alkali metal salts by a sol–gel method. The influences of the kinds of alkali metal salts and heating temperature on the reaction of the titanium precursor compounds with the alkali metal salts, its phase transition, and crystal growth were investigated by thermal analyses, XRD measurement, and SEM observation in order to prepare lithium, sodium, and potassium titanates at relatively low temperatures. The amorphous titania gel or its product, very small titania crystals, as an intermediate phase reacted with the alkali metal salts at around 500–600 °C while it was still highly active and formed alkali metal titanate nanoparticles before forming the stable titania crystals. It is important that the active amorphous titania gels react with the dispersed alkali metal salts at a temperature as low as possible in order to form the alkali metal titanate nanocrystals. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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9. Use of 3D domain swapping in constructing supramolecular metalloproteins.
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Hirota, Shun, Mashima, Tsuyoshi, and Kobayashi, Naoya
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METALLOPROTEINS ,COORDINATION polymers ,SINGLE molecules ,SUPRAMOLECULES ,MYOGLOBIN ,DRUG delivery systems ,CYTOCHROME c - Abstract
Supramolecules, which are formed by assembling multiple molecules by noncovalent intermolecular interactions instead of covalent bonds, often show additional properties that cannot be exhibited by a single molecule. Supramolecules have evolved into molecular machines in the field of chemistry, and various supramolecular proteins are responsible for life activities in the field of biology. The design and creation of supramolecular proteins will lead to development of new enzymes, functional biomaterials, drug delivery systems, etc.; thus, the number of studies on the regulation of supramolecular proteins is increasing year by year. Several methods, including disulfide bond, metal coordination, and surface–surface interaction, have been utilized to construct supramolecular proteins. In nature, proteins have been shown to form oligomers by 3D domain swapping (3D-DS), a phenomenon in which a structural region is exchanged between molecules of the same protein. We have been studying the mechanism of 3D-DS and utilizing 3D-DS to construct supramolecular metalloproteins. Cytochrome c forms cyclic oligomers and polymers by 3D-DS, whereas other metalloproteins, such as various c-type cytochromes and azurin form small oligomers and myoglobin forms a compact dimer. We have also utilized 3D-DS to construct heterodimers with different active sites, a protein nanocage encapsulating a Zn–SO
4 cluster in the internal cavity, and a tetrahedron with a designed building block protein. Protein oligomer formation was controlled for the 3D-DS dimer of a dimer-monomer transition protein. This article reviews our research on supramolecular metalloproteins. [ABSTRACT FROM AUTHOR]- Published
- 2021
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10. Semi-automated tracking of pain in critical care patients using artificial intelligence: a retrospective observational study.
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Kobayashi, Naoya, Shiga, Takuya, Ikumi, Saori, Watanabe, Kazuki, Murakami, Hitoshi, and Yamauchi, Masanori
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CRITICALLY ill ,PAIN measurement ,MACHINE learning ,CRITICAL care medicine ,PAIN - Abstract
Monitoring the pain intensity in critically ill patients is crucial because intense pain can cause adverse events, including poor survival rates; however, continuous pain evaluation is difficult. Vital signs have traditionally been considered ineffective in pain assessment; nevertheless, the use of machine learning may automate pain assessment using vital signs. This retrospective observational study was performed at a university hospital in Sendai, Japan. Objective pain assessments were performed in eligible patients using the Critical-Care Pain Observation Tool (CPOT). Three machine-learning methods—random forest (RF), support vector machine (SVM), and logistic regression (LR)—were employed to predict pain using parameters, such as vital signs, age group, and sedation levels. Prediction accuracy was calculated as the harmonic mean of sensitivity, specificity, and area under the receiver operating characteristic curve (AUROC). Furthermore, 117,190 CPOT assessments were performed in 11,507 eligible patients (median age: 65 years; 58.0% males). We found that pain prediction was possible with all three machine-learning methods. RF demonstrated the highest AUROC for the test data (RF: 0.853, SVM: 0.823, and LR: 0.787). With this method, pain can be objectively, continuously, and semi-automatically evaluated in critically ill patients. [ABSTRACT FROM AUTHOR]
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- 2021
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11. Impact of marginal resection for hepatocellular carcinoma.
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Kobayashi, Naoya, Aramaki, Osamu, Midorikawa, Yutaka, Higaki, Tokio, Nakayama, Hisashi, Moriguchi, Masamichi, and Takayama, Tadatoshi
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HEPATOCELLULAR carcinoma ,PROPENSITY score matching ,SURGICAL site ,MULTIVARIATE analysis - Abstract
Purpose: The surgical margin for liver resection to treat hepatocellular carcinoma (HCC) is occasionally < 1 mm. This study determined the impact of a surgical margin < 1 mm [marginal resection (MR)] on the types of recurrence and the prognosis in solitary HCC. Methods: The data of 454 patients undergoing curative liver resection for solitary HCC in our institution were analyzed. The patients were divided into the MR (n = 90) and non-MR (n = 364) groups. The clinicopathological data and outcomes after liver resection were compared. A case-matching analysis using a propensity scoring method was also performed. Results: The recurrence-free survival was significantly and overall survival was marginally significantly lower in the MR group than in the non-MR group (p = 0.012–0.051, respectively). According to a multivariate analysis, MR was not a significant independent factor for recurrence-free survival (p = 0.056). After propensity score matching, there were no significant differences in the recurrence-free and overall survival between the two groups (p = 0.375–0.496, respectively). Furthermore, there were no significant differences in the intrahepatic recurrence patterns between the two groups before and after matching. Conclusion: MR for solitary HCC might be sufficient in patients with a limited liver functional reserve. [ABSTRACT FROM AUTHOR]
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- 2020
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12. Favorable outcomes of surgical resection for extrahepatic recurrent hepatocellular carcinoma.
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Midorikawa, Yutaka, Takayama, Tadatoshi, Nakayama, Hisashi, Moriguchi, Masamichi, Aramaki, Osamu, Yamazaki, Shintaro, Teramoto, Kenichi, Yoshida, Nao, Kobayashi, Naoya, Tsuji, Shingo, and Higaki, Tokio
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SURGICAL excision ,HEPATOCELLULAR carcinoma ,RADIOEMBOLIZATION ,ADRENAL glands ,SURGICAL complications ,LYMPH nodes - Abstract
Aim: Repeat resection for intrahepatic recurrent hepatocellular carcinoma (HCC) is effective for the long‐term survival of patients; however, little is known about the surgical outcomes of extrahepatic nodules. The aim of this study is to investigate whether resection can contribute to the survival of patients with extrahepatic recurrent HCC. Methods: Under the conditions that intrahepatic recurrent HCC was absent or controlled by locoregional therapies, patients who had resectable extrahepatic recurrent HCC in the lymph nodes, adrenal gland, peritoneum, lung, or brain were included in this study. The survival of patients who did (Surgical group) and did not (Non‐surgical group, underwent other therapies) undergo resection for extrahepatic recurrent HCC was compared. Results: Thirty‐eight and 26 patients were included in the Surgical and Non‐surgical groups, respectively. No patient had severe postoperative complications. After a median follow‐up of 1.2 (range, 0.2–8.8) years, the median cumulative incidence of extrahepatic recurrent HCC was 1.2 years (95% confidence interval [CI], 0.4–3.5) in the Surgical group. The median overall survival was 5.3 (95% CI, 2.5–8.8) and 1.1 (0.8–2.3) years in the Surgical and Non‐surgical groups, respectively (P < 0.001). The 5‐year rates of survival were 60.5% and 9.1% in the Surgical and Non‐surgical groups, respectively. Surgical resection, α‐fetoprotein, disease‐free interval, and metastasis at the adrenal gland were the independent factors for overall survival. Conclusions: Due to the favorable surgical outcomes, resection should be considered as one of the therapeutic choices for patients with extrahepatic recurrent HCC if intrahepatic recurrent HCC can be controlled by locoregional therapies. [ABSTRACT FROM AUTHOR]
- Published
- 2020
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13. Be careful of splenic rupture caused by hit by a pitch during a baseball game: a case report.
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Kobayashi, Naoya, Kano, Hisao, Kuwana, Tsukasa, Nakagawa, Katsuhiro, Matsuoka, Masaru, Ihara, Shingo, Sawada, Nami, Yamaguchi, Junko, and Kinoshita, Kosaku
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PITCHING (Baseball) ,SPLENECTOMY ,BASEBALL competitions ,SPLENIC rupture ,BATTING (Baseball) ,BASEBALL ,CURRICULUM - Abstract
Background: To the best of our knowledge, splenic rupture caused by hit by a pitch (HBP) has not been previously reported. We present a patient who underwent emergency laparotomy for splenic rupture after being HBP during a baseball game.Case Presentation: A 41-year-old male was HBP in the left abdomen during his first at-bat during a baseball game. During the operation, vascular injury of the splenic hilum and a deeply extending parenchymal injury were observed, and splenectomy was performed. Histologic findings were consistent with splenic rupture.Conclusions: The patient's postoperative course was uneventful. Although extremely rare, the possibility of intra-abdominal organ injury should be considered in batters who are hit in the abdomen by a pitched baseball, as illustrated by our patient. [ABSTRACT FROM AUTHOR]- Published
- 2021
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14. Arterial blood pressure correlates with 90-day mortality in sepsis patients: a retrospective multicenter derivation and validation study using high-frequency continuous data.
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Kobayashi, Naoya, Nakagawa, Atsuhiro, Kudo, Daisuke, Ishigaki, Tsukasa, Ishizuka, Haruya, Saito, Kohji, Ejima, Yutaka, Wagatsuma, Toshihiro, Toyama, Hiroaki, Kawaguchi, Tomohiro, Niizuma, Kuniyasu, Ando, Kokichi, Kurotaki, Kenji, Kumagai, Michio, Kushimoto, Shigeki, Tominaga, Teiji, and Yamauchi, Masanori
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- 2019
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15. 4.4 V supercapacitors based on super-stable mesoporous carbon sheet made of edge-free graphene walls.
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Nomura, Keita, Nishihara, Hirotomo, Kobayashi, Naoya, Asada, Toshihiro, and Kyotani, Takashi
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- 2019
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16. Insight into the origin of carbon corrosion in positive electrodes of supercapacitors.
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Tang, Rui, Taguchi, Kaishi, Nishihara, Hirotomo, Ishii, Takafumi, Morallón, Emilia, Cazorla-Amorós, Diego, Asada, Toshihiro, Kobayashi, Naoya, Muramatsu, Yasuji, and Kyotani, Takashi
- Abstract
While activated carbons are used as electrode materials in commercial supercapacitors, they are not stable under high voltage operation especially at a positive-electrode side, and this limits the working voltage of supercapacitors to about 2.8 V in organic electrolytes. Thus, revealing the specific carbon chemical structures causing the corrosion is of great significance to come up with ideas of avoiding the corrosion reactions and eventually to achieve high energy density by expanding the working voltage. In this work, a variety of carbon materials are analyzed with many characterization techniques such as X-ray diffraction, Raman spectroscopy, N
2 adsorption, magnetic susceptibility measurement, and temperature programmed desorption up to 1800 °C, to find out the origin of corrosion reactions in an organic electrolyte. While carbon crystallinity and porosity are not directly related to the positive-electrode corrosion, a good correlation is found between the corrosion charge and the number of carbon edge sites terminated by H and oxygen-functional groups which are decomposed and release CO. It is thus concluded that the H-terminated edge sites, phenol, ether and carbonyl groups are electroactive sites for the carbon materials used in the positive electrode of supercapacitors. [ABSTRACT FROM AUTHOR]- Published
- 2019
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17. A Novel Preservation Solution Containing a JNK Inhibitory Peptide Efficiently Improves Islet Yield for Porcine Islet Isolation.
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Noguchi, Hirofumi, Miyagi-Shiohira, Chika, Nakashima, Yoshiki, Ebi, Nana, Hamada, Eri, Tamaki, Yoshihito, Kuwae, Kazuho, Kitamura, Shinji, Kobayashi, Naoya, Saitoh, Issei, and Watanabe, Masami
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- 2019
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18. A Liquid Chromatography with Tandem Mass Spectrometry-Based Proteomic Analysis of Primary Cultured Cells and Subcultured Cells Using Mouse Adipose-Derived Mesenchymal Stem Cells.
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Nakashima, Yoshiki, Nahar, Saifun, Miyagi-Shiohira, Chika, Kinjo, Takao, Kobayashi, Naoya, Saitoh, Issei, Watanabe, Masami, Fujita, Jiro, and Noguchi, Hirofumi
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MESENCHYMAL stem cells ,PROTEIN expression ,LIQUID chromatography-mass spectrometry ,CELL culture ,CELLULAR therapy ,REGENERATIVE medicine - Abstract
Adipose-derived mesenchymal stem cells (MSC-ATs) are representative cell sources for cell therapy. However, how cell stress resulting from passage influences the MSC-AT protein expression has been unclear. In this study, a protein expression analysis was performed by liquid chromatography with tandem mass spectrometry (LC-MS/MS) using mouse primary cultured cells (P0) and cells passaged three times (P3) as samples. A total of 256 proteins were classified as cellular process-related proteins, while 179 were classified as metabolic process-related proteins in P0. These were considered to be adaptive responses of the cells to an in vitro environment. However, seven proteins of growth were identified (Csf1, App, Adam15, Alcam, Tbl1xr1, Ninj1, and Sbds) in P0. In addition, four proteins of antioxidant activity were also identified (Srxn1, Txndc17, Fam213b, and Apoe) in P0. We identified 1139 proteins expressed in both P0 and P3 cells that had their expression decreased to 69.4% in P3 cells compared with P0 cells, but 1139 proteins are very likely proteins that are derived from MSC-AT. The function of MSC-ATs was maintained after three passages. However, the LC-MS/MS analysis data showed that the protein expression was degraded after three passages. MSC-ATs retained about 70% of their protein expression ability in P3 cells. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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19. Age-related changes in factors associated with delayed extubation after general anesthesia: a retrospective study.
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Kobayashi, Naoya, Wagatsuma, Toshihiro, Shiga, Takuya, Toyama, Hiroaki, Ejima, Yutaka, and Yamauchi, Masanori
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EXTUBATION ,GENERAL anesthesia ,RETROSPECTIVE studies - Abstract
Although delayed extubation occurs more frequently in older than younger patients, age-related changes in factors influencing extubation times remain relatively unexplored. In the >= 65 years group, delayed extubation was associated with age ( I P i < 0.001), cervical surgery ( I P i < 0.001), abdominal surgery ( I P i = 0.032), and orthopedic surgery ( I P i = 0.028). [Extracted from the article]
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- 2020
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20. A Comparison of the Preservation of Mouse Adipose Tissue-Derived Mesenchymal Stem Cells Using the University of Wisconsin Solution and Hank’s Balanced Salt Solution.
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Nahar, Saifun, Nakashima, Yoshiki, Miyagi-Shiohira, Chika, Kinjo, Takao, Kobayashi, Naoya, Saitoh, Issei, Watanabe, Masami, Noguchi, Hirofumi, and Fujita, Jiro
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ADIPOSE tissues ,MESENCHYMAL stem cells ,CELL survival ,TRANSPLANTATION of organs, tissues, etc. - Abstract
Preservation of adipose tissue before the isolation of cells is one of the most important steps in maintaining the cell viability of adipose tissue-derived mesenchymal stem cells (ADSCs) for clinical use. Hank’s balanced salt solution (HBSS) is one of the main ADSC preservation solutions used clinically. However, this step is known to lead to decreased cell viability. The University of Wisconsin (UW) solution is recognized by transplant physicians as an excellent organ preservation solution. We aimed to investigate the effectiveness of UW solution in preservation of the viability of ADSCs. We collected adipose tissue from the inguinal fat pad of mice and compared preservation in UW solution and HBSS overnight by measuring cell viability after isolation. We found that the number of viable cells harvested per gram of adipose tissue mass was higher in UW solution- than HBSS-preserved tissue. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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21. Characterization of induced tissue-specific stem cells from pancreas by a synthetic self-replicative RNA.
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Miyagi-Shiohira, Chika, Nakashima, Yoshiki, Kobayashi, Naoya, Saitoh, Issei, Watanabe, Masami, and Noguchi, Hirofumi
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- 2018
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22. Significant Effect of Pore Sizes on Energy Storage in Nanoporous Carbon Supercapacitors.
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Young, Christine, Lin, Jianjian, Wang, Jie, Ding, Bing, Zhang, Xiaogang, Alshehri, Saad M., Ahamad, Tansir, Salunkhe, Rahul R., Hossain, Shahriar A., Khan, Junayet Hossain, Ide, Yusuke, Kim, Jeonghun, Henzie, Joel, Wu, Kevin C.‐W., Kobayashi, Naoya, and Yamauchi, Yusuke
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MESOPOROUS silica ,MESOPOROUS materials ,POROSITY ,SUPERCAPACITORS ,MATERIALS - Abstract
Abstract: Mesoporous carbon can be synthesized with good control of surface area, pore‐size distribution, and porous architecture. Although the relationship between porosity and supercapacitor performance is well known, there are no thorough reports that compare the performance of numerous types of carbon samples side by side. In this manuscript, we describe the performance of 13 porous carbon samples in supercapacitor devices. We suggest that there is a “critical pore size” at which guest molecules can pass through the pores effectively. In this context, the specific surface area (SSA) and pore‐size distribution (PSD) are used to show the point at which the pore size crosses the threshold of critical size. These measurements provide a guide for the development of new kinds of carbon materials for supercapacitor devices. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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23. Self‐Template‐Directed Metal–Organic Frameworks Network and the Derived Honeycomb‐Like Carbon Flakes via Confinement Pyrolysis.
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Wang, Jie, Tang, Jing, Ding, Bing, Chang, Zhi, Hao, Xiaodong, Takei, Toshiaki, Kobayashi, Naoya, Bando, Yoshio, Zhang, Xiaogang, and Yamauchi, Yusuke
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- 2018
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24. A proteome analysis of pig pancreatic islets and exocrine tissue by liquid chromatography with tandem mass spectrometry.
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Nakashima, Yoshiki, Miyagi-Shiohira, Chika, Kobayashi, Naoya, Saitoh, Issei, Watanabe, Masami, and Noguchi, Hirofumi
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- 2017
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25. Ferroelectric and magnetic properties for nano particles of multiferroic YbFe 2 O 4.
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Kobayashi, Hiroyuki, Fujiwara, Kosuke, Kobayashi, Naoya, Karasudani, Tomoyuki, Sakai, Masahiro, Ikeda, Naoshi, Mori, Shigeo, and Seri, Osami
- Subjects
YTTERBIUM compounds ,FERROELECTRICITY ,MAGNETIC properties of metals ,METAL nanoparticles ,MULTIFERROIC materials - Abstract
Size effect and lattice strain effect for charge ordered structure and magnetic properties were investigated on the nano particles of geometrically spin and charge frustrated system YbFe2O4. The lattice strain of the nano particle was controlled with the ratio of Yb and Fe (2.00 ≤ Fe/Yb ≤ 2.04) in liquid synthesizing method. It was found that the lattice strain is not affected by the magnetic transition temperature, however the anomalous behavior at a lower magnetic transition (TLT) with an increment of the Fe / Yb ratio was detected. The development of charge ordering was two-dimensional and magnetic ordering goes down for all samples in spite of the variation of the local lattice strain. This is the first report of the coupling of charge and spin ordering to the size effect in this material. These results suggest that the discussion on the electric polarization induced from the charge ordering in this material need to care the long-range interaction like surface effect. [ABSTRACT FROM AUTHOR]
- Published
- 2017
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26. Ultrahigh performance supercapacitors utilizing core–shell nanoarchitectures from a metal–organic framework-derived nanoporous carbon and a conducting polymer.
- Author
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Salunkhe, Rahul R., Tang, Jing, Kobayashi, Naoya, Kim, Jeonghun, Ide, Yusuke, Tominaka, Satoshi, Kim, Jung Ho, and Yamauchi, Yusuke
- Published
- 2016
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27. A high-performance supercapacitor cell based on ZIF-8-derived nanoporous carbon using an organic electrolyte.
- Author
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Salunkhe, Rahul R., Young, Christine, Tang, Jing, Takei, Toshiaki, Ide, Yusuke, Kobayashi, Naoya, and Yamauchi, Yusuke
- Subjects
CARBON ,NANOPOROUS materials ,SUPERCAPACITORS ,ZEOLITES ,STORAGE batteries - Abstract
Low-cost supercapacitors have the ability to rapidly store a large amount of charge, which makes them the best alternative to batteries in portable electronics. Here, we demonstrate the fabrication of all-carbon supercapacitors using an organic electrolyte. By using ZIF-derived nanoporous carbon electrodes, we have realized a high-performance supercapacitor cell using 2 M NEt
4 BF4 /PC as the electrolyte. Our device shows good energy storage capacity that is comparable to the other previously reported supercapacitors. [ABSTRACT FROM AUTHOR]- Published
- 2016
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- View/download PDF
28. Hepatocytes.
- Author
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Soto-Gutierrez, Alejandro, Navarro-Alvarez, Nalu, and Kobayashi, Naoya
- Abstract
The ability of the liver to regenerate was recognized by the Greeks in the ancient myth of Prometheus, the Titan god of forethought, who gave fire to the mortals and angered Zeus. Zeus then punished him for his crime by having him bound to a rock while a great eagle ate his liver every day only to have it grow back to be eaten again the next day [1]. In contrast to other solid organs, the human liver has the unique ability to regenerate after toxic injury, chronic inflammation, and surgical resection and is able to restore its original mass, cellular structure and functions [1–3]. [ABSTRACT FROM AUTHOR]
- Published
- 2011
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- View/download PDF
29. Hepatic Stem Cells and Liver Development.
- Author
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Navarro-Alvarez, Nalu, Soto-Gutierrez, Alejandro, and Kobayashi, Naoya
- Published
- 2010
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- View/download PDF
30. A preliminary study for constructing a bioartificial liver device with induced pluripotent stem cell-derived hepatocytes.
- Author
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Iwamuro, Masaya, Shiraha, Hidenori, Nakaji, Shuhei, Furutani, Masumi, Kobayashi, Naoya, Takaki, Akinobu, and Yamamoto, Kazuhide
- Subjects
PLURIPOTENT stem cells ,LIVER cells ,BIOREACTORS ,IMMUNOLOGY ,ENDODERM - Abstract
Background: Bioartificial liver systems, designed to support patients with liver failure,are composed of bioreactors and functional hepatocytes. Immunological rejection of the embedded hepatocytes by the host immune system is a serious concern that crucially degrades the performance of the device. Induced pluripotent stem (iPS) cells are considered a desirable source for bioartificial liver systems, because patient-derived iPS cells are free from immunological rejection. The purpose of this paper was to test the feasibility of a bioartificial liver system with iPS cell-derived hepatocyte-like cells.Methods: Mouse iPS cells were differentiated into hepatocyte-like cells by a multi-step differentiation protocol via embryoid bodies and definitive endoderm. Differentiation of iPS cells was evaluated by morphology, PCR assay, and functional assays. iPS cell-derived hepatocyte-like cells were cultured in a bioreactor module with a pore size of 0.2 μm for 7 days. The amount of albumin secreted into the circulating medium was analyzed by ELISA. Additionally, after a 7-day culture in a bioreactor module, cells were observed by a scanning electron microscope.Results: At the final stage of the differentiation program, iPS cells changed their morphology to a polygonal shape with two nucleoli and enriched cytoplasmic granules. Transmission electron microscope analysis revealed their polygonal shape,glycogen deposition in the cytoplasm, microvilli on their surfaces, and a duct-like arrangement. PCR analysis showed increased expression of albumin mRNA over the course of the differentiation program. Albumin and urea production was also observed.iPS-Heps culture in bioreactor modules showed the accumulation of albumin in the medium for up to 7 days. Scanning electron microscopy revealed the attachment of cell clusters to the hollow fibers of the module. These results indicated that iPS cells were differentiated into hepatocyte-like cells after culture for 7 days in a bioreactor module with a pore size of 0.2 μm.Conclusion: We consider the combination of a bioreactor module with a 0.2-μm pore membrane and embedded hepatocytes differentiated from iPS cells to be a promising option for bioartificial liver systems. This paper provides the basic concept and preliminary data for an iPS cell-oriented bioartificial liver system.PACS code: 87. Biological and medical physics, 87.85.-d Biomedical engineering, 87.85.Lf Tissue engineering, 87.85.Tu Modeling biomedical systems. [ABSTRACT FROM AUTHOR]
- Published
- 2012
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31. Effect of Risedronate on Osteoblast Differentiation, Expression of Receptor Activator of NF-κB Ligand and Apoptosis in Mesenchymal Stem Cells.
- Author
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Fujita, Hirofumi, Kurokawa, Kazuko, Ogino, Tetsuya, Ono, Mio, Yamamoto, Masanao, Oka, Takashi, Nakanishi, Tohru, Kobayashi, Naoya, Tanaka, Noriaki, Ogawa, Tomohiro, Suzaki, Etsuko, Utsumi, Kozo, and Sasaki, Junzo
- Subjects
DIPHOSPHONATES ,MESENCHYMAL stem cells ,OSTEOCLASTS ,APOPTOSIS ,RECEPTOR-ligand complexes ,WESTERN immunoblotting - Abstract
Nitrogen-containing bisphosphonates (BPs) are antiresorptive drugs used for the treatment of metabolic bone diseases. Bone marrow stromal cells such as mesenchymal stem cells (MSCs) and MSC-derived osteoblasts that originate from MSCs are known to regulate osteoclast differentiation and activation via the expression of receptor activator of NF-
K B ligand (RANKL). Although the effects of nitrogen-containing BPs on osteoclasts and osteoblasts have been well investigated, their effects in MSCs have not been clarified. In this study, we investigated the effects of risedronate (RIS), a nitrogen-containing BP, on osteoblast differentiation, RANKL expression and apoptosis in human and rat MSCs. RIS suppressed the formation of mineralized nodules and mRNA expression of differentiation marker genes such as bone sialoprotein and osteocalcin in MSC-derived osteoblasts. The RANKL expression induced by 1,25-(OH)2 vitamin D3 was not affected by RIS in human MSC-derived osteoblasts. In addition, treatment with high-concentration RIS induced chromatin condensation, an apoptosis feature, in MSCs. RIS-induced chromatin condensation was suppressed by a pan-caspase inhibitorZ VAD-FMK and a cellpermeable isoprenoid analogue geranylgeraniol. These results indicate that RIS suppressed osteoblast differentiation and induced caspase- and isoprenoid depletion-dependent apoptosis and suggest that the antiresorptive effect of RIS is not mediated by a decrease in the RANKL expression in MSC-derived osteoblasts. [ABSTRACT FROM AUTHOR]- Published
- 2011
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- View/download PDF
32. Organ reengineering through development of a transplantable recellularized liver graft using decellularized liver matrix.
- Author
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Uygun, Basak E., Soto-Gutierrez, Alejandro, Yagi, Hiroshi, Izamis, Maria-Louisa, Guzzardi, Maria A., Shulman, Carley, Milwid, Jack, Kobayashi, Naoya, Tilles, Arno, Berthiaume, Francois, Hertl, Martin, Nahmias, Yaakov, Yarmush, Martin L., and Uygun, Korkut
- Subjects
LIVER transplantation ,LIVER failure ,TISSUE engineering ,REGENERATIVE medicine ,REGENERATION (Biology) ,BIOMEDICAL engineering - Abstract
Orthotopic liver transplantation is the only available treatment for severe liver failure, but it is currently limited by organ shortage. One technical challenge that has thus far limited the development of a tissue-engineered liver graft is oxygen and nutrient transport. Here we demonstrate a novel approach to generate transplantable liver grafts using decellularized liver matrix. The decellularization process preserves the structural and functional characteristics of the native microvascular network, allowing efficient recellularization of the liver matrix with adult hepatocytes and subsequent perfusion for in vitro culture. The recellularized graft supports liver-specific function including albumin secretion, urea synthesis and cytochrome P450 expression at comparable levels to normal liver in vitro. The recellularized liver grafts can be transplanted into rats, supporting hepatocyte survival and function with minimal ischemic damage. These results provide a proof of principle for the generation of a transplantable liver graft as a potential treatment for liver disease. [ABSTRACT FROM AUTHOR]
- Published
- 2010
- Full Text
- View/download PDF
33. Low-Temperature Preservation of Isolated Islets is Superior to Conventional Islet Culture Before Islet Transplantation.
- Author
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Noguchi, Hirofumi, Naziruddin, Bashoo, Jackson, Andrew, Shimoda, Masayuki, Ikemoto, Tetsuya, Fujita, Yasutaka, Chujo, Daisuke, Takita, Morihito, Kobayashi, Naoya, Onaca, Nicholas, Levy, Marlon F., and Matsumoto, Shinichi
- Published
- 2010
- Full Text
- View/download PDF
34. Bone Repair by Transplantation of hTERT-Immortalized Human Mesenchymal Stem Cells in Mice.
- Author
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Nakahara, Hiroyuki, Misawa, Haruo, Hayashi, Takahiro, Kondo, Eisaku, Yuasa, Takeshi, Kubota, Yasuhiro, Seita, Masayuki, Kawamoto, Hironobu, Hassan, Wael A. R. A., Hassan, Reham A. R. A., Javed, Shahid M., Tanaka, Masato, Endo, Hirosuke, Noguchi, Hirofumi, Matsumoto, Shinichi, Takata, Katsuyoshi, Tashiro, Yuichi, Nakaji, Shuhei, Ozaki, Toshifumi, and Kobayashi, Naoya
- Published
- 2009
- Full Text
- View/download PDF
35. Iodixanol-Controlled Density Gradient During Islet Purification Improves Recovery Rate in Human Islet Isolation.
- Author
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Noguchi, Hirofumi, Ikemoto, Tetsuya, Naziruddin, Bashoo, Jackson, Andrew, Shimoda, Masayuki, Fujita, Yasutaka, Chujo, Daisuke, Takita, Morihito, Kobayashi, Naoya, Onaca, Nicholas, Levy, Marlon F., and Matsumoto, Shinichi
- Published
- 2009
- Full Text
- View/download PDF
36. Differentiating Stem Cells into Liver.
- Author
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SOTO-GUTIERREZ, ALEJANDRO, BASMA, HESHAM, NAVARRO-ALVAREZ, NALU, UYGUN, BASAK E., YARMUSH, MARTIN L., KOBAYASHI, NAOYA, and FOX, IRA J.
- Subjects
EMBRYONIC stem cells ,LIVER cells ,STEM cells ,CELLS ,LIVER - Abstract
The article considers the challenges and future opportunities in development and use of embryonic stem (ES) cell-derived liver cells. ES cell technology provides the opportunity to create functional differentiated hepatocytes for in vitro analysis. Innovations in microfabrication and bioimaging technologies have allowed microscale control and evaluation of the cellular microenvironment in vitro.
- Published
- 2008
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- View/download PDF
37. Hepatocyte transplantation: a step forward.
- Author
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Navarro-Alvarez, Nalu, Soto-Gutierrez, Alejandro, and Kobayashi, Naoya
- Published
- 2007
- Full Text
- View/download PDF
38. Comparison of M-Kyoto Solution and Histidine-Tryptophan-Ketoglutarate Solution With a Trypsin Inhibitor for Pancreas Preservation in Islet Transplantation.
- Author
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Noguchi, Hirofumi, Ueda, Michiko, Hayashi, Shuji, Kobayashi, Naoya, Nagata, Hideo, Iwanaga, Yasuhiro, Okitsu, Teru, and Matsumoto, Shinichi
- Published
- 2007
- Full Text
- View/download PDF
39. Cell-Permeable Pentapeptide V5 Inhibits Apoptosis and Enhances Insulin Secretion, Allowing Experimental Single-Donor Islet Transplantation in Mice.
- Author
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Rivas-Carrillo, Jorge D., Soto-Gutierrez, Alejandro, Navarro-Alvarez, Nalu, Noguchi, Hirofumi, Okitsu, Teru, Chen, Yong, Yuasa, Takeshi, Tanaka, Kimiaki, Narushima, Michiki, Mild, Atsushi, Misawa, Haruo, Tabata, Yasuhiko, Jun, Hee-Sook, Matsumoto, Shinichi, Fox, Ira J., Tanaka, Noriaki, and Kobayashi, Naoya
- Subjects
TREATMENT of diabetes ,PEOPLE with diabetes ,ISLANDS of Langerhans transplantation ,INSULIN ,APOPTOSIS - Abstract
OBJECTIVE--Treatment of diabetic patients by pancreatic islet transplantation often requires the use of islets from two to four donors to produce insulin independence in a single recipient. Following isolation and transplantation, islets are susceptible to apoptosis, which limits their function and probably long-term islet graft survival. RESEARCH DESIGN AND METHODS--To address this issue, we examined the effect of the cell-permeable apoptosis inhibitor pentapeptide Val-Pro-Met-Leu-Lys, V5, on pancreatic islets in a mouse model. RESULTS--V5 treatment upregulated expression of anti-apoptotic proteins Bcl-2 and XIAP (X-linked inhibitor of apoptosis protein) by more than 3- and 11-fold and downregulated expression of apoptosis-inducing proteins Bax, Bad, and nuclear factor-κB-p65 by 10, 30, and nearly 50%, respectively. Treatment improved the recovered islet mass following collagenase digestion and isolation by 44% and in vitro glucose-responsive insulin secretion nearly fourfold. Following transplantation in streptozotocin-induced diabetic mice, 150 V5-treated islet equivalents functioned as well as 450 control untreated islet equivalents in normalizing blood glucose. CONCLUSIONS--These studies indicate that inhibition of apoptosis by V5 significantly improves islet function following isolation and improves islet graft function following transplantation. Use of this reagent in clinical islet transplantation could have a dramatic impact on the number of patients that might benefit from this therapy and could affect long-term graft survival. Diabetes 56:1259-1267, 2007 [ABSTRACT FROM AUTHOR]
- Published
- 2007
- Full Text
- View/download PDF
40. Construction and Transplantation of an Engineered Hepatic Tissue Using a Polyaminourethane-Coated Nonwoven Polytetrafluoroethylene Fabric.
- Author
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Soto-Gutierrez, Alejandro, Navarro-Alvarez, Nalu, Rivas-Carrillo, Jorge D., Tanaka, Kimiaki, Chen, Yong, Misawa, Haruo, Okitsu, Teru, Noguchi, Hirofumi, Tanaka, Noriaki, and Kobayashi, Naoya
- Published
- 2007
- Full Text
- View/download PDF
41. Current Cell-based Approaches for the Treatment of Diabetes Mellitus.
- Author
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Rivas-Carrillo, Jorge David, Okitsu, Teru, and Kobayashi, Naoya
- Subjects
DIABETES ,MESENCHYME ,EMBRYONIC stem cells ,CELLULAR therapy ,CONNECTIVE tissues - Abstract
The article describes the potential cell-based approaches for the treatment of diabetes mellitus. It discusses the role of the surrounding mesenchyme in providing most of the regulatory factors for the proper pancreatic development. An overview of the differentiation of embryonic stem cells into pancreatic ß-like-cells is offered. It is stated that the discovery of multipotent stem cells in adult tissue has resulted in a widespread belief in the possible effectiveness of cell therapy.
- Published
- 2007
- Full Text
- View/download PDF
42. Follow-up Study of the First Successful Living Donor Islet Transplantation.
- Author
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Matsumoto, Shinichi, Okitsu, Teru, Iwanaga, Yasuhiro, Noguchi, Hirofumi, Nagata, Hideo, Yonekawa, Yukihide, Liu, Xiaoling, Kamiya, Hiroki, Ueda, Michiko, Hatanaka, Nobuyo, Kobayashi, Naoya, Yamada, Yuichiro, Miyakawa, Shuichi, Seino, Yutaka, Shapiro, A M. James, and Tanaka, Koichi
- Published
- 2006
- Full Text
- View/download PDF
43. Stem cell-derived hepatocytes.
- Author
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Navarro-Alvarez, Nalu, Soto-Gutierrez, Alejandro, Rivas-Carrillo, Jorge David, Fox, Ira J, Tanaka, Noriaki, and Kobayashi, Naoya
- Published
- 2006
- Full Text
- View/download PDF
44. Reversal of mouse hepatic failure using an implanted liver-assist device containing ES cell–derived hepatocytes.
- Author
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Soto-Gutiérrez, Alejandro, Kobayashi, Naoya, Rivas-Carrillo, Jorge David, Navarro-Álvarez, Nalu, Debaio Zhao, Okitsu, Teru, Noguchi, Hirofumi, Basma, Hesham, Tabata, Yashuhiko, Yong Chen, Tanaka, Kimiaki, Narushima, Michiki, Miki, Atsushi, Ueda, Tadayoshi, Hee-Sook Jun, Ji-Won Yoon, Lebkowski, Jane, Tanaka, Noriaki, and Fox, Ira J.
- Subjects
LIVER failure ,IMMUNOSUPPRESSION ,EMBRYONIC stem cells ,CELLULAR therapy ,LIVER cells - Abstract
Severe acute liver failure, even when transient, must be treated by transplantation and lifelong immune suppression. Treatment could be improved by bioartificial liver (BAL) support, but this approach is hindered by a shortage of human hepatocytes. To generate an alternative source of cells for BAL support, we differentiated mouse embryonic stem (ES) cells into hepatocytes by coculture with a combination of human liver nonparenchymal cell lines and fibroblast growth factor-2, human activin-A and hepatocyte growth factor. Functional hepatocytes were isolated using albumin promoter–based cell sorting. ES cell–derived hepatocytes expressed liver-specific genes, secreted albumin and metabolized ammonia, lidocaine and diazepam. Treatment of 90% hepatectomized mice with a subcutaneously implanted BAL seeded with ES cell–derived hepatocytes or primary hepatocytes improved liver function and prolonged survival, whereas treatment with a BAL seeded with control cells did not. After functioning in the BAL, ES cell–derived hepatocytes developed characteristics nearly identical to those of primary hepatocytes. [ABSTRACT FROM AUTHOR]
- Published
- 2006
- Full Text
- View/download PDF
45. A New Mouse Model for Intraportal Islet Transplantation with Limited Hepatic Lobe as a Graft Site.
- Author
-
Yonekawa, Yukihide, Okitsu, Teru, Wake, Kenjiro, Iwanaga, Yasuhiro, Noguchi, Hirofumi, Nagata, Hideo, Liu, Xiaoling, Kobayashi, Naoya, and Matsumoto, Shinichi
- Published
- 2006
- Full Text
- View/download PDF
46. A human β-cell line for transplantation therapy to control type 1 diabetes.
- Author
-
Narushima, Michiki, Kobayashi, Naoya, Okitsu, Teru, Tanaka, Yoshihito, Shun-Ai Li, Yong Chen, Miki, Atsushi, Tanaka, Kimiaki, Nakaji, Shuhei, Takei, Kohji, Gutierrez, Alejandro Soto, Rivas-Carrillo, Jorge David, Navarro-Álvarez, Nalu, Hee-Sook Jun, Westerman, Karen A., Noguchi, Hirofumi, Lakey, Jonathan R. T., Leboulch, Philippe, Tanaka, Noriaki, and Ji-Won Yoon
- Subjects
TRANSPLANTATION of organs, tissues, etc. ,CELL lines ,DIAGNOSIS of diabetes ,CELL culture ,DNA polymerases ,PROTEINS - Abstract
A human pancreatic β-cell line that is functionally equivalent to primary β-cells has not been available. We established a reversibly immortalized human β-cell clone (NAKT-15) by transfection of primary human β-cells with a retroviral vector containing simian virus 40 large T-antigen (SV40T) and human telomerase reverse transcriptase (hTERT) cDNAs flanked by paired loxP recombination targets, which allow deletion of SV40T and TERT by Cre recombinase. Reverted NAKT-15 cells expressed β-cell transcription factors (Isl-1, Pax 6, Nkx 6.1, Pdx-1), prohormone convertases 1/3 and 2, and secretory granule proteins, and secreted insulin in response to glucose, similar to normal human islets. Transplantation of NAKT-15 cells into streptozotocin-induced diabetic severe combined immunodeficiency mice resulted in perfect control of blood glucose within 2 weeks; mice remained normoglycemic for longer than 30 weeks. The establishment of this cell line is one step toward a potential cure of diabetes by transplantation. [ABSTRACT FROM AUTHOR]
- Published
- 2005
- Full Text
- View/download PDF
47. Fasudil hydrochloride hydrate, a Rho-kinase (ROCK) inhibitor, suppresses collagen production and enhances collagenase activity in hepatic stellate cells.
- Author
-
Fukushima, Marie, Nakamuta, Makoto, Kohjima, Motoyuki, Kotoh, Kazuhiro, Enjoji, Munechika, Kobayashi, Naoya, and Nawata, Hajime
- Subjects
COLLAGEN ,EXTRACELLULAR matrix proteins ,LIVER cells ,APOPTOSIS ,CELL death ,SMOOTH muscle ,GENE expression ,GENETIC regulation - Abstract
Fukushima M, Nakamuta M, Kohjima M, Kotoh K, Enjoji M, Kobayashi N, Nawata H. Fasudil hydrochloride hydrate, a Rho-kinase (ROCK) inhibitor, suppresses collagen production and enhances collagenase activity in hepatic stellate cells. Liver International 2005: 25: 829–838. © Blackwell Munksgaard 2005 The Rho–ROCK signaling pathways play an important role in the activation of hepatic stellate cells (HSCs). We investigated the effects of fasudil hydrochloride hydrate (fasudil), a Rho-kinase (ROCK) inhibitor, on cell growth, collagen production, and collagenase activity in HSCs. Rat HSCs and human HSC-derived TWNT-4 cells were cultured for studies on stress fiber formation and α-smooth muscle actin (α-SMA) expression. Proliferation was measured by BrdU incorporation, and apoptosis by TUNEL assay. The phosphorylation states of the MAP kinases (MAPKs), extra cellular signal –regulated kinase 1/2 (ERK1/2), c-jun kinase (JNK), and p38 were evaluated by western blot analysis. Type I collagen, matrix metalloproteinase-1 (MMP-1) and tissue inhibitor of matrix metalloproteinase-1 (TIMP-1) production and gene expression were evaluated by ELISA and real-time PCR, respectively. Collagenase activity (active MMP-1) was also evaluated. Fasudil (100 μM) inhibited cell spreading, the formation of stress fibers, and expression of α-SMA with concomitant suppression of cell growth, although it did not induce apoptosis. Fasudil inhibited phosphorylation of ERK1/2, JNK, and p38. Treatment with fasudil suppressed the production and transcription of collagen and TIMP, stimulated the production and transcription of MMP-1, and enhanced collagenase activity. These findings demonstrated that fasudil not only suppresses proliferation and collagen production but also increases collagenase activity. [ABSTRACT FROM AUTHOR]
- Published
- 2005
- Full Text
- View/download PDF
48. Gene delivery to embryonic stem cells.
- Author
-
Kobayashi, Naoya, Rivas-Carrillo, Jorge David, Soto-Gutierrez, Alejandro, Fukazawa, Takuya, Chen, Yong, Navarro-Alvarez, Nalu, and Tanaka, Noriaki
- Published
- 2005
- Full Text
- View/download PDF
49. Development of a Porcine Model of Type 1 Diabetes by Total Pancreatectomy and Establishment of a Glucose Tolerance Evaluation Method.
- Author
-
Kobayashi, Kazuya, Kobayashi, Naoya, Okitsu, Teru, Yong, Chen, Fukazawa, Takuya, Ikeda, Hideaki, Kosaka, Yoshikazu, Narushima, Michiki, Arata, Takashi, and Tanaka, Noriaki
- Subjects
DIABETES ,PANCREATECTOMY ,GLUCOSE tolerance tests ,SWINE ,PATHOLOGICAL physiology ,INSULIN - Abstract
Purpose: To develop and evaluate the efficacy of diabetes-targeted cell therapies in humans, a reliable model in larger animals is highly desirable. This article reports the surgical technique of total pancreatectomy in pigs and the biochemical analysis of the characteristics of totally pancreatectomized pigs. Methods: Surgical total pancreatectomy was conducted in 23 pigs. Blood glucose, insulin, biochemistries, activity index, and intravenous glucose tolerance test (IVGTT) were examined to assess the pathophysiological profiles of diabetic pigs. Results: A total of 14 pigs successfully underwent total pancreatectomy without requiring biliary reconstruction and were analyzed in the present study. Activity index was decreased from day 5 on and the mean survival of totally pancreatectomized pigs was 7.6 ± 2.7 days. No endogenous insulin secretion was confirmed in these pigs. Pigs which received total pancreatectomy demonstrated significantly higher levels of ketone bodies. IVGTT performed within 4 days after total pancreatectomy showed a spontaneous decrease in blood glucose levels despite an absence of endogenous insulin secretion. IVGTT on day 5 or later showed continued hyperglycemia in pigs with total pancreatectomy. Histological examination showed atrophy of hepatocytes and decreased glycogen storage in the liver and decreased mucus production of the small intestine. Conclusion: This article describes a porcine model of diabetes created by total pancreatectomy and it analyzes the pathophysiological profiles in the animals. The present study has suggested that IVGTT on day 5 or later after total pancreatectomy is a reliable method to evaluate the efficacy of cell therapies. [ABSTRACT FROM AUTHOR]
- Published
- 2004
- Full Text
- View/download PDF
50. Adenovirus Mediated Gene Transduction of Primarily Isolated Mouse Islets.
- Author
-
Narushima, Michiki, Okitsu, Teru, Miki, Atsushi, Yong, Chen, Kobayashi, Kazuya, Yonekawa, Yukihide, Tanaka, Kimiaki, Ikeda, Hideaki, Matsumoto, Shinichi, Tanaka, Noriaki, and Kobayashi, Naoya
- Published
- 2004
- Full Text
- View/download PDF
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