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Background: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has spread rapidly since 2019, and the number of reports regarding long COVID has increased. Although the distribution of long COVID depends on patient characteristics, epidemiological data on Japanese patients are limited. Hence, this study aimed to investigate the distribution of long COVID in Japanese patients. This study is the first nationwide Japanese prospective cohort study on long COVID., Methods: This multicenter, prospective cohort study enrolled hospitalized COVID-19 patients aged ≥18 years at 26 Japanese medical institutions. In total, 1200 patients were enrolled. Clinical information and patient-reported outcomes were collected from medical records, paper questionnaires, and smartphone applications., Results: We collected data from 1066 cases with both medical records and patient-reported outcomes. The proportion of patients with at least one symptom decreased chronologically from 93.9% (947/1009) during hospitalization to 46.3% (433/935), 40.5% (350/865), and 33.0% (239/724) at 3, 6, and 12 months, respectively. Patients with at least one long COVID symptom showed lower quality of life and scored higher on assessments for depression, anxiety, and fear of COVID-19. Female sex, middle age (41-64 years), oxygen requirement, and critical condition during hospitalization were risk factors for long COVID., Conclusions: This study elucidated the symptom distribution and risks of long COVID in the Japanese population. This study provides reference data for future studies of long COVID in Japan., Competing Interests: Conflict of Interest Norihiro Harada reports personal fees from AstraZeneca K.K., GlaxoSmithKline, Kyorin, Novartis Japan, Sanofi and grants from AstraZeneca, Daikin, Kyorin, SRL Medisearch, outside the submitted work. Other authors have no conflicts of interest., (Copyright © 2023. Published by Elsevier B.V.)

Reports of eosinophilic pneumonia (EP) as a side effect of dupilumab administration are limited in previous studies. Herein, we report two cases in which EP developed subsequent to the administration of dupilumab for eosinophilic chronic rhinosinusitis (ECRS). Case 1: A 55-year-old woman presented with ECRS, eosinophilic otitis media, and bronchial asthma, and was treated with dupilumab for ECRS. Five weeks later, fever and dyspnea developed, and infiltration shadows were observed in her lungs. The peripheral blood eosinophil count (PBEC) was 3848/μL (26%), bronchoalveolar lavage fluid showed eosinophilic infiltration, and EP was subsequently diagnosed. Her condition improved following prednisolone treatment. Case 2: A 59-year-old man presented with fatigue and dyspnea after receiving dupilumab for ECRS. He had infiltrative shadows throughout his left lung field, and his PBEC was 4850/μL (26.5%). Prednisolone was initiated, and his condition improved. EP developed in both patients during the period of elevated PBEC after dupilumab administration, and dupilumab was suspected to be the causative agent in their EP. Hence, EP should be considered as a differential diagnosis when fever and dyspnea appear following dupilumab administration.

BACKGROUND Diffuse alveolar hemorrhage (DAH) caused by direct oral anticoagulants (DOACs) has increased in recent years with the increase in prescriptions of DOACs. Generally, DOACs are considered to have a lower bleeding risk than the traditional anticoagulant, warfarin. However, major bleeding, including DAH, due to DOACs can be seen in clinical practice, and there are few reports to elucidate when DOAC-associated alveolar hemorrhage occurs and whether DOAC-induced DAH has a trigger. CASE REPORT An 80-year-old man diagnosed and treated for atrial fibrillation with apixaban 2.5 mg twice daily for 1 year before admission, underwent 2 invasive medical procedures over a short period of time. Hemoptysis began after the procedures. He experienced shortness of breath and rapidly progressive hypoxic respiratory failure. His postsurgical oxygen saturation level dropped rapidly. Chest radiography and computed tomography images showed pulmonary infiltration and ground-glass opacity in both lungs. Apixaban treatment was discontinued, and mechanical ventilation was initiated. Bronchoalveolar lavage cytology revealed hemosiderin-laden macrophages. A diagnosis of diffuse alveolar hemorrhage (DAH) was made. In previous reports about DAH caused by DOACs, most patients had bleeding triggers; drug interactions in patients taking DOACs are one of such triggers. Although DOACs are relatively safe for elderly patients, DAH can occur in patients receiving either early-stage or long-term treatment. CONCLUSIONS The onset of DOAC-associated DAH is not limited to the early stages of medication initiation. Various triggers can induce DAH in patients receiving DOACs.

Food allergy is a typical immediate-onset allergic disease in which symptoms are provoked by exposure to the sensitized antigens. Although previous reports have shown that omalizumab has helped children with egg or milk allergy achieve oral immunotherapy safely, there is still no established method for induction of remission in adult food allergy. A 51-year-old woman with oral steroid-dependent severe asthma was treated with omalizumab for 6 years. She had shellfish and wheat food allergy and oral allergy syndrome induced by kiwi and other foods associated with latex-fruit syndrome. Since omalizumab treatment, her food allergy symptoms had disappeared. After 7 years of this treatment, disseminated erythema suddenly appeared; omalizumab was discontinued because of suspected drug-induced eruption. After omalizumab interruption, she felt an itching sensation in her throat with worsened asthma control immediately after wheat ingestion. Readministration of omalizumab improved these symptoms. Thus, we raised the possibility that omalizumab not only improved asthma control but also induced pharmacological remission of the patient's food allergy. Omalizumab may be considered as a treatment option for adult patients with food allergies and severe asthma., Competing Interests: Conflict of Interest: K. Fukunaga received lecture fees from AstraZeneca and Boehringer-Ingelheim. The other authors have no conflict of interest to declare., (Copyright © 2021. Asia Pacific Association of Allergy, Asthma and Clinical Immunology.)

Among several mechanisms for the resistance of human epidermal growth factor receptor 2-overexpressing (HER2 +) cancer cells to trastuzumab, little is known regarding the mechanism underlying the resistance to trastuzumab-mediated antibody-dependent cellular cytotoxicity (ADCC). Cell death due to ADCC is caused by apoptosis of target cells induced by granzymes released from natural killer cells. Because optimal granzyme physiological activity occurs at neutral pH, we assumed that the pH of the intracellular environment influences the cytotoxic effects of granzymes. We established ADCC-resistant cells and compared them with wild-type cells in terms of the expression of intracellular pH-regulating genes. The expression of ATP6V1B1, which encodes a component of vacuolar ATPases, was downregulated in the ADCC-resistant cells. Thus, to functionally characterize ATP6V1B1, we used a CRISPR/Cas9 system to generate ATP6V1B1-knockout SKBR3 and JIMT-1 cells (both HER2 + human breast cancer cell line). The resulting cells exhibited significantly less ADCC than the control SKBR3 and JIMT-1 cells. The intracellular pH of the ATP6V1B1-knockout SKBR3 and JIMT-1 cells was significantly lower than control SKBR3 and JIMT-1cells. An analysis of granzyme dynamics during the ADCC reaction in cancer cells revealed that granzymes degraded intracellularly in the control SKBR3 and JIMT-1 cells and accumulated in ATP6V1B1-knockout cells, but were not cytotoxic. These findings suggest that decreased vacuolar ATPase activity alters the cytoplasmic pH of cancer cells to create an environment that is less suitable for granzyme bioactivity, which adversely affects the induction of apoptosis of cancer cells by NK cells.

A 31-year-old female physician was diagnosed with bilateral pneumothorax a day after her acupuncture treatment. Her body mass index was 16.9 and she did not have a prior history of respiratory disease or smoking. Acupuncture needles may easily reach the pleura around the end of the suprascapular angle of the levator scapulae muscle where the subcutaneous tissue is anatomically thin. In our patient, the thickness between the epidermis and the visceral pleura in this area was only 22 mm as confirmed by an ultrasound scan. Although she felt chest discomfort 30 min after the procedure, she assumed the symptom to be a reaction to the acupuncture. In light of our case, we advise practitioners to select appropriate acupuncture needles for patients based on the site of insertion and counsel them regarding the appearance of symptoms such as chest pain and dyspnoea immediately after the procedure., Competing Interests: Competing interests: None declared., (© BMJ Publishing Group Limited 2021. No commercial re-use. See rights and permissions. Published by BMJ.)

Background: It has been reported that the gene expression profile of peripheral blood mononuclear cells (PBMCs) exhibits a unique gene expression signature in several types of cancer. In this study, we aimed to explore the breast cancer patient-specific gene expression profile of PBMCs and discuss immunological insight on host antitumor immune responses., Methods: We comprehensively analyzed the gene expression of PBMCs by RNA sequencing in the breast cancer patients as compared to that of healthy volunteers (HVs). Pathway enrichment analysis was performed on MetaCore tm to search the molecular pathways associated with the gene expression profile of PBMCs in cancer patients compared with HVs., Results: We found a significant unique gene expression signature, such as the Toll-like receptor (TLR) 3- and TLR4-induced Toll/interleukin-1 receptor domain-containing adapter molecule 1 (TICAM1)-specific signaling pathway in the breast cancer patients as compared to that of healthy volunteers. Distinctive immunological gene expression profiles also showed the possibility of classifying breast cancer patients into subgroups such as T-cell inhibitory and monocyte-activating groups independent of known phenotypes of breast cancer., Conclusions: These preliminary findings suggest that evaluation of gene expression patterns of PBMCs might be both a less invasive diagnostic procedure and a useful way to reveal immunological insight of breast cancer, including biomarkers for cancer immunotherapy, such as immune checkpoint inhibitor therapy.

Systemic inflammation has been associated with aggressive tumor growth, invasion, and metastasis. Here we performed a comprehensive analysis of 26 kinds of inflammatory cytokine expression patterns among 185 patients with breast cancer and 54 healthy volunteers followed by chemometric analysis. We identified the specific cytokine expression patterns of breast cancer patients compared to healthy volunteers with (1) VEGF, IL-9, GM-CSF, IL-13, IL-4, and IFNγ, (2) IL-8, IL-10, IL-12, IL-5, IL-7, IL-1α, GCSF, IL-1β, and TNFα and (3) IL-2, Eotaxin, MIP1β, MIP1α, IL-17, and bFGF. Among the patients with breast cancer, we identified the specific cytokine signature of metastatic patients compared to non-metastatic patients. We also established a mathematical model for distinguishing patients with breast cancer from healthy volunteers and metastatic patients from non-metastatic patients. This cytokine network analysis could provide new insights into early intervention and effective therapeutic strategy for patients with breast cancer.

Lantibiotic nukacin ISK-1 is produced by Staphylococcus warneri ISK-1. The dual functional transporter NukT, an ABC transporter maturation and secretion protein, contributes to cleavage of the leader peptide from the prepeptide (modified NukA) and the final transport of nukacin ISK-1. NukT consists of an N-terminal peptidase domain (PEP), a C-terminal nucleotide-binding domain (NBD), and a transmembrane domain (TMD). In this study, NukT and its peptidase-inactive mutant were expressed, purified, and reconstituted into liposomes for analysis of their peptidase and ATPase activities. The ATPase activity of the NBD region was shown to be required for the peptidase activity of the PEP region. Furthermore, we demonstrated for the first time that leader peptide cleavage by the PEP region significantly enhanced the ATPase activity of the NBD region. Taken together, the presented results offer new insights into the processing mechanism of lantibiotic transporters and the necessity of interdomain cooperation.

Neuropilin-1 (NRP-1)-expressing macrophages are engaged in antitumor immune functions via various mechanisms. In this study, we investigated the role of NRP-1 on macrophages in antibody-mediated tumoricidal activity. Treatment of macrophages with NRP-1 knockdown or an anti-NRP-1-neutralizing antibody significantly suppressed antibody-dependent cellular cytotoxicity and modulated cytokine secretion from macrophages in vitro. Furthermore, in vivo studies using a humanized mouse model bearing human epidermal growth factor receptor-2 (HER2)-positive breast cancer xenografts showed that antibody-mediated antitumor activity and tumor infiltration of CD4 + T lymphocytes were significantly downregulated when peripheral blood mononuclear cells in which NRP-1 was knocked down were co-administered with an anti-HER2 antibody. These results revealed that NRP-1 expressed on macrophages plays an important role in antibody-mediated antitumor immunity. Taken together, the induction of NRP-1 on macrophages may be a therapeutic indicator for antibody treatments that exert antibody-dependent cellular cytotoxicity activity, although further studies are needed in order to support this hypothesis.

Background: Donor lymphocyte infusion (DLI) is used for treatment of hematologic malignancy relapse or mixed chimerism after allogeneic hematopoietic stem cell transplantation. Although graft-versus-host disease is well recognized as one of the adverse effects of DLI, there are limited reports on noninfectious pulmonary complications (NIPCs) after DLI., Case Report: A 55-year-old woman with acute myeloid leukemia received DLI for conversion from recipient predominant to complete donor chimerism on Day +193 after allogeneic HSCT. Eight weeks later, she complained of dyspnea with fever; chest computed tomography revealed diffuse, bilateral, ground glass opacity and reticular appearance. She was diagnosed as having NIPC based on serum and bronchoalveolar lavage fluid (BALF) findings. She was successfully treated with prednisolone (PSL) and completely recovered., Discussion: We analyzed the cell profile from the BALF and 27 cytokines and chemokines in the serum using the Bio-Plex platform. The cells consisted of recipient predominant macrophages and T cells. The serum cytokine and chemokine profile showed significant elevation of interleukin (IL)-1β, IL-6, IL-8, tumor necrosis factor-α, macrophage inflammatory protein (MIP)-1α, and MIP-1β, which declined with the improvement of symptoms after initiation of PSL treatment., Conclusion: Inflammatory effectors by recipient cells, rather than allogeneic responses by donor cells, played an important role in the pathogenesis of NIPCs after DLI in the present case., (© 2015 AABB.)

Lantibiotics are antibacterial peptides containing unique thioether cross-links termed lanthionine and methyllanthionine. NukM, the modifying enzyme of nukacin ISK-1, which is produced by Staphylococcus warneri ISK-1, catalyzes the dehydration of specific Ser/Thr residues in a precursor peptide, followed by conjugative addition of intramolecular Cys to dehydrated residues to generate a cyclic structure. By contrast, the precursor peptide of nisin is modified by 2 enzymes, NisB and NisC, which mediate dehydration and cyclization, respectively. While the C-terminal domain of NukM is homologous to NisC, the N-terminal domain has no homology with other known proteins. We expressed and characterized the N- and C-terminal domains of NukM, NukMN, and NukMC, separately. In vitro reconstitution revealed that full-length NukM fully modified the substrate peptide NukA. NukMN partially phosphorylated, dehydrated, and cyclized NukA. By contrast, NukMC did not catalyze dehydration, phosphorylation, or cyclization reactions. Interaction studies using surface plasmon resonance analysis indicated that NukM and NukMN can bind NukA with high affinity, whereas NukMC has low substrate-recognition activity. These results suggest that NukMN is mainly responsible for substrate recognition and dehydration and that the whole NukM structure, including the C-terminal domain, is required for the complete modification of NukA. To the best of our knowledge, this is the first report providing insights into the in vitro catalytic activity of individual domains of a LanM-type modification enzyme., (Copyright © 2015 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.)

Colovesical fistula (CVF) resulting from colon diverticulosis is a comparatively rare disease, and neither the diagnosis nor treatment has been established. Our experience with CVF due to sigmoid diverticulitis over a 9-year period was reviewed to clarify the clinical presentation and diagnostic confirmation. Ten patients with CVF were identified in this period, and chief complaints, laboratory findings, presenting symptoms, diagnostic investigations, and subsequent treatments were reviewed. Preoperative urinalysis showing bacteriuria (100%) was the most common presentation, followed by fecaluria (40%), abdominal pain (40%), pneumaturia (30%), hematuria (30%), pain on urination (30%), pollakiuria (10%), and dysuria (10%). The abilities of various preoperative investigations to identify CVF were: computed tomography (CT), 88.9%; magnetic resonance imaging, 40%; cystoscopy, 30%, and gastrografin irrigoscopy, 22.2%. Colonoscopy (0%) was not diagnostic. Bowel resection was performed in nine of ten patients. When inflammation was intense, covering ileostomy was performed, and an omental plasty was placed between the bowel anastomosis and bladder. When CVF is suspected, we recommend CT followed by colonoscopy and cystoscopy as a first-line investigation to rule out malignancy as a cause. Other modalities should only be used if the diagnosis is in doubt or additional information is needed to plan operative management. Primary colic anastomosis appears to be safely performed by applying omental plasty and covering ileostomy.

Background: Trogocytosis is defined as the transfer of cell-surface membrane proteins and membrane patches from one cell to another through contact. It is reported that human epidermal growth factor receptor 2 (HER2) could be transferred from cancer cells to monocytes via trogocytosis; however, the clinical significance of this is unknown. The aim of this study is to demonstrate the presence and evaluate the clinical significance of HER2(+) tumor-infiltrated immune cells (arising through HER2 trogocytosis) in HER2-overexpressing (HER2+) breast cancer patients receiving trastuzumab-based primary systemic therapy (PST)., Methods: To assess the trogocytosis of HER2 from cancer cells to immune cells, and to evaluate the up- and down-regulation of HER2 on immune and cancer cells, peripheral blood mononuclear cells from healthy volunteers and breast cancer patients were co-cultured with HER2+ and HER2-negative breast cancer cell lines with and without trastuzumab, respectively. The correlation between HER2 expression on tumor-infiltrated immune cells and a pathological complete response (pCR) in HER2+ breast cancer patients treated with trastuzumab-based PST was analyzed., Results: HER2 was transferred from HER2+ breast cancer cells to monocytes and natural killer cells by trogocytosis. Trastuzumab-mediated trogocytosed-HER2(+) effector cells exhibited greater CD107a expression than non-HER2-trogocytosed effector cells. In breast cancer patients, HER2 expression on tumor-infiltrated immune cells in treatment naïve HER2+ tumors was associated with a pCR to trastuzumab-based PST., Conclusions: HER2-trogocytosis is visible evidence of tumor microenvironment interaction between cancer cells and immune cells. Given that effective contact between these cells is critical for immune destruction of target cancer cells, this interaction is of great significance. It is possible that HER2 trogocytosis could be used as a predictive biomarker for trastuzumab-based PST efficacy in HER2(+) breast cancer patients.

Radiofrequency ablation (RFA) therapy combined with hepatectomy was performed in 5 patients with synchronous liver metastases of colorectal cancer. RFA of liver metastases was performed using a Cool-tip electrode (Radionics; Burlington, MA, USA). The ablation time used in each session varied according to the tumor size and intraoperative impedance. In 2 patients, hepatectomy and resection of the colorectal primary lesion were performed synchronously. In patients with multiple liver metastases, relative curative resection was performed using the complementary RFA. In the other 3 patients, synchronous hepatectomy was considered difficult and systematic chemotherapy was performed after resection of the colorectal primary lesion. After systematic chemotherapy, the range of hepatectomy was restricted for liver injury, but relative curative resection was performed using RFA therapy. Computed tomography performed after hepatectomy showed that the region that underwent RFA appeared necrotic with a safety margin. The average observation period was 25 months (maximal survival period, 50 months) and 3 of the patients are alive.

We report a case of adenocarcinoma of the small intestine responding to XELOX chemotherapy, leading to a partial metabolic response(PMR). The patient was a 58-year-old male with multiple peritoneal dissemination of adenocarcinoma of the small intestine. Chemotherapy with XELOX(L-OHP 130 mg/m² on day 1 , and capecitabine 1,000 mg/m2 on days 1-14)was performed. After 4 courses, a significant tumor reduction was obtained. This case suggests that chemotherapy with XELOX is a potential regimen for small intestinal adenocarcinoma.

Bacteriocins are ribosomally synthesized antibacterial peptides produced by bacteria that inhibit the growth of similar or closely related bacterial strains. A number of bacteriocins from a wide variety of bacteria have been discovered, and their diverse structures have been reported. Growing evidence suggests that bacteriocins have diverse structures, modes of action, mechanisms of biosynthesis and self-immunity, and gene regulation. Bacteriocins are considered as an attractive compound in food and pharmaceutical industries to prevent food spoilage and pathogenic bacterial growth. Furthermore, elucidation of their biosynthesis has led to the use of bacteriocin-controlled gene-expression systems and the biosynthetic enzymes of lantibiotics, a class of bacteriocins, as tools to design novel peptides. In this review, we summarize and discuss currently known information on bacteriocins produced by Gram-positive bacteria and their applications.

Ring A of nukacin ISK-1, which is also present in different type-A(II) lantibiotics, resembles a lipid II-binding motif (TxS/TxD/EC, x denotes undefined residues) similar to that present in mersacidin (type-B lantibiotics), which suggests that nukacin ISK-1 binds to lipid II as a docking molecule. Results from our experiments on peptidoglycan precursor (UDP-MurNAc-pp) accumulation and peptide antagonism assays clearly indicated that nukacin ISK-1 inhibits cell-wall biosynthesis, accumulating lipid II precursor inside the cell, and the peptide activity can be repressed by lipid I and lipid II. Interaction analysis of nukacin ISK-1 and different ring A variants with lipid II revealed that nukacin ISK-1 and nukacin D13E (a more active variant) have a high affinity (K(D) = 0.17 and 0.19 μM, respectively) for lipid II, whereas nukacin D13A (a less active variant) showed a lower affinity, and nukacin C14S (a negative variant lacking the ring A structure) exhibited no interaction. Therefore, on the basis of the structural similarity and positional significance of the amino acids in this region, we concluded that nukacin ISK-1 binds lipid II via its ring A region and may lead to the inhibition of cell-wall biosynthesis., (© 2012 American Chemical Society)

Nukacin D13E (D13E) is a variant of type-A(II) lantibiotic nukacin ISK-1 produced by Staphylococcus warneri ISK-1. D13E exhibited a twofold higher specific antimicrobial activity than nukacin ISK-1 against a number of Gram-positive bacteria. We previously reported the heterologous production of D13E in Lactococcus lactis NZ9000 under the control of nisin-controlled gene expression system. In this study, we demonstrated enhanced production of D13E by the additional expression of immunity genes, nukFEG. The nukacin ISK-1 immunity, conferred by the ABC transporter complex, NukFEG, and the lantibiotic-binding protein, NukH, was not overwhelmed by D13E. The additional NukFEG resulted in a fourfold increase in the immunity level of the strain and a 5.2-fold increase in D13E production. The additional NukFEGH-expressing strain with the highest D13E immunity showed reduced level of production. Further improvement in D13E production was achieved by using pH-controlled batch fermentation.

We analyzed retrospectively the surgical outcomes of diverticular diseases of the colon at the surgical division of Fukuyama Medical Center. Data were collected from 39 patients who underwent surgery for diverticular disease at Fukuyama Medical Center. Thirty-nine patients were admitted between 2005 and 2010. The mean age of the 39 patients was 63.6 years. The collected data included patient demographics, patient history, type of surgery and complications. Patients were divided into 2 groups, Elective vs. Emergent group, right vs. left colon group and laparotomy vs. laparoscopic approach. Multivariate analysis of the logistic model of morbidity revealed a significantly higher rate in the left colon and the Cox proportional hazards model clearly showed fewer postoperative hospital days with the laparoscopic approach. Surgical procedures should be decided in reference to the particular clinical and pathological features of diverticular disease to gain an acceptable morbidity and mortality rates.

Lantibiotics are ribosomally synthesized, post-translationally modified, peptide antibiotics containing unusual amino acids such as dehydrated amino acids and lanthionine. These unusual amino acids impose conformational constraints on the peptide and contribute to the biological activity and high physicochemical stability of lantibiotics. Recent researches on the modification enzymes responsible for dehydration and cyclization have considerably increased our understanding of their molecular characteristics and relaxed specificity. These insights enabled us to exploit these modification enzymes for developing new lantibiotic variants with improved therapeutic potential. Several methodologies have been explored to engineer novel lantibiotics. Here, we outline the current knowledge of modification enzymes. We also describe the methodologies and strategies used to engineer lantibiotics and provide some examples of successful generation of lantibiotics with enhanced activity.

Lantibiotics are ribosomally synthesized and post-translationally modified peptide antibiotics that contain unusual amino acids such as dehydro and lanthionine residues. Nukacin ISK-1 is a class II lantibiotic, whose precursor peptide (NukA) is modified by NukM to form modified NukA. ATP-binding cassette (ABC) transporter NukT is predicted to cleave off the N-terminal leader peptide of modified NukA and secrete the mature peptide. Multiple sequence alignments revealed that NukT has an N-terminal peptidase domain (PEP) and a C-terminal ATP binding domain (ABD). Previously, in vitro reconstitution of NukT has revealed that NukT peptidase activity depends on ATP hydrolysis. Here, we constructed a series of NukT mutants and investigated their transport activity in vivo and peptidase activity in vitro. Most of the mutations of the conserved residues of PEP or ABD resulted in failure of nukacin ISK-1 production and accumulation of modified NukA inside the cells. NukT(N106D) was found to be the only mutant capable of producing nukacin ISK-1. Asn(106) is conserved as Asp in other related ABC transporters. Additionally, an in vitro peptidase assay of NukT mutants demonstrated that PEP is on the cytosolic side and all of the ABD mutants as well as PEP (with the exception of NukT(N106D)) did not have peptidase activity in vitro. Taken together, these observations suggest that the leader peptide is cleaved off inside the cells before peptide secretion; both PEP and ABD are important for NukT peptidase activity, and cooperation between these two domains inside the cells is indispensable for proper functioning of NukT.

The emergence of drug-resistant microorganisms is an important medical and social problem. Drug-resistant microorganisms are thought to grow selectively in the presence of antibiotics. Most clinically isolated drug-resistant microorganisms have mutations in the target genes for the drugs. While any of the many mutagens in the environment may cause such genetic mutations, no reports have yet described whether these mutagens can confer drug resistance to clinically important microorganisms. We investigated how environmental mutagens might be implicated in acquired resistance to antibiotics in clinically important microorganisms, which causes human diseases. We selected mutagens found in the environment, in cigarette smoke, or in drugs, and then exposed Pseudomonas aeruginosa to them. After exposure, the incidence of rifampicin- and ciprofloxacin-resistant P. aeruginosa strains markedly increased, and we found mutations in genes for the antibiotic-target molecule. These mutations were similar to those found in drug-resistant microorganisms isolated from clinical samples. Our findings show that environmental mutagens, and an anticancer drug, are capable of inducing drug-resistant P. aeruginosa similar to strains found in clinical settings., (© 2011 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.)

NukT, a possible ABC transporter maturation and secretion (AMS) protein, may contribute to the cleavage of the leader peptide of NukA, which is the prepeptide of the lantibiotic nukacin ISK-1, and to nukacin ISK-1 transport. In this study, we reconstituted in vitro peptidase activity of the full-length NukT overexpressed in inside-out membrane vesicles of Staphylococcus carnosus TM300. We found that the presence of unusual amino acids in NukA is required for leader peptide cleavage. Furthermore, NukT peptidase activity was inhibited by phenylmethylsulfonyl fluoride, a serine/cysteine protease inhibitor; this finding strongly suggests that NukT, like other AMS proteins, is a cysteine protease. Interestingly, NukT peptidase activity depended on ATP hydrolysis. These results suggest that the N-terminal peptidase domain of NukT may cooperatively function with the C-terminal ATP-binding domain. This is the first in vitro study on lantibiotics that reports the processing mechanism of a full-length bifunctional ABC transporter.

A 25-year-old man with RS rectal cancer received a radical resection of the original tumor and lymph node dissection. Oral tegafur/uracil (UFT)/Leucovorin (LV) therapy has been used for adjuvant chemotherapy, as the pathological Stage was T3N1M0, Stage IIIa. After 10 months from operation, multiple liver metastases were recognized and not resectable. So a systemic chemotherapy by mFOLFOX6+bevacizumab was begun via CV port. After 5 courses of mFOLFOX6+bevacizumab, abdominal CT revealed liver metastases showed remarkable reduction in size. Hepatic resection of S6 segment was enforced, and the patient uneventfully discharged. Pathological findings of S6 segment revealed no residual cancer cells, indicating the histological effect of mFOLFOX6+bevacizumab was Grade 3. And no liver damage was recognized.

A 41-year-old man with multiple liver metastases from sigmoid colon cancer received a radical resection of the original tumor and 16 courses of weekly high-dose 5-FU(WHF)chemotherapy via hepatic arterial reservoir. The metastatic lesions showed stable disease(SD), and systemic chemotherapy by mFOLFOX6 was begun via CV port. After 14 courses of mFOLFOX4, abdominal CT revealed liver metastases were remarkably reduced in size. Hepatic resection of lateral segment and radio frequency ablation(RFA)for S6 were enforced, and the patient was uneventfully discharged. Pathological findings of lateral segment revealed no residual cancer cells, indicating that the histological effect of mFOLFOX6 was Grade 3.

Hepatocyte transplantation is effective for treating liver failure, but healthy donors as a source of hepatocytes are quite limited. The livers of patients with hepatic fibrosis could be an alternative source; however, few reports have examined the nature of hepatocytes from fibrotic livers (f-hepatocytes). In this study, we compared the growth of f-hepatocytes and hepatocytes from normal livers (n-hepatocytes). Hepatocytes were isolated from normal and CCl(4)-treated wild-type Fischer rats that express dipeptidyl dipeptidase IV (DPPIV) gene (DPPIV(+)). The n- and f-hepatocytes proliferated in culture at similar rates. Both types of hepatocytes were transplanted into DPPIV(-) mutant Fischer rats that had been treated with retrorsine to injure the liver and were partially hepatectomized (PHx) before transplantation. Both n- and f-DPPIV(+)-hepatocytes proliferated and formed colonies. The colony sizes of f-hepatocytes 21 days posttransplantation were approximately three times those of n-hepatocytes. The hepatocytes were analyzed using a fluorescence activated cell sorter (FACS). The FACS profile differed between f- and n-hepatocytes: f-hepatocytes were less granular, less autofluorescent, and smaller than n-hepatocytes. These characteristics of f-hepatocytes resembled those reported for small-sized n-hepatocytes (SHs), which are highly proliferative and preferentially express a unique set of 10 SH genes. However, f-hepatocytes preferentially expressed only five of the SH genes. The expression profile of f-hepatocytes was rather similar to that of proliferating n-hepatocytes in the regenerating liver after PHx. The f-hepatocytes were morphologically normal and did not show any preneoplastic phenotype. These normal and proliferative natures of f-hepatocytes in vivo suggest the fibrotic liver as a source of hepatocytes for transplantation.

Recently, we revealed that microtubule-associated protein (MAP) 4 isoforms, which differ in the number of repeat sequences, alter the microtubule surface properties, and we proposed a hypothesis stating that the change in the surface properties may regulate the movements of microtubule motors [Tokuraku et al. (2003) J Biol Chem 278: 29609-29618]. In this study, we examined whether MAP4 isoforms affect the kinesin motor activity. When the MAP4 isoforms were present in an in vitro gliding assay, the five-repeat isoform but not the three- and four-repeat isoforms inhibited the movement of the microtubules in a concentration-dependent manner. The observation of individual microtubules revealed that in the presence of the five-repeat isoform, the microtubules completely stopped their movements or recurrently paused and resumed their movements, with no deceleration in the moving phase. The result can be explained by assuming that kinesin stops its movement when it encounters a microtubular region whose properties are altered by the MAPs. A sedimentation assay demonstrated that the MAP4 isoforms did not compete with kinesin for binding to microtubules, indicating that kinesin can bind to the MAP-bound microtubules, although it cannot move on them.

The histologic hallmark of Parkinson disease (PD) is loss of pigmented neurons in the substantia nigra (SN) and locus ceruleus (LC) with accumulation of alpha-synuclein (alphaS). It has been reported that tyrosine hydroxylase (TH)-negative pigmented neurons are present in these nuclei of patients with PD. However, the relationship between TH immunoreactivity and alphaS accumulation remains uncertain. We immunohistochemically examined the SN and LC from patients with PD (n = 10) and control subjects (n = 7). A correlation study indicated a close relationship among decreased TH immunoreactivity, alphaS accumulation, and neuronal loss. In addition, 10% of pigmented neurons in the SN and 54.9% of those in the LC contained abnormal alphaS aggregates. Moreover, 82.3% of pigmented neurons bearing alphaS aggregates in the SN and 39.2% of those in the LC lacked TH immunoreactivity, suggesting that pigmented neurons in the SN have a greater tendency to lack TH activity than those in the LC. Recent studies have shown that this decrease of TH activity leads to a decrease of cytotoxic substances and that decreased dopamine synthesis leads to a reduction of cytotoxic alphaS oligomers. Therefore, the decrease of TH immunoreactivity in pigmented neurons demonstrated here can be considered to represent a cytoprotective mechanism in PD.

Here we report an autopsy case of hypoglycemic encephalopathy with prolonged coma. Laboratory data obtained when the patient lapsed into a coma showed that she had a low level of serum glucose (27 mg/dL). Although the level of glucose returned to within the normal range rapidly after glucose infusion, the patient remained in a coma for 22 months. It was presumed that the state of hypoglycemia persisted for about 4 h. There was no evidence of hypotension or hypoxia. Magnetic resonance imaging was performed 3 h after glucose administration; diffusion-weighted images revealed hyperintensity in the cerebral white matter and in the boundary zone between the middle and posterior cerebral arteries. Post-mortem examination revealed superficial laminar necrosis throughout the cerebral cortex. Neuronal necrosis was also found in the hippocampus and dentate gyrus, although the CA3 region appeared normal. In addition to these lesions, which are consistent with hypoglycemia-induced brain damage, the cerebral white matter exhibited severe loss of myelin and axons with reactive astrocytosis and macrophage infiltration. Old infarcts were also present in the bilateral occipital lobes. Since the cerebral blood flow is reported to be decreased during severe hypoglycemia, the present findings suggest that white matter lesions and boundary-zone infarctions may develop primarily in uncomplicated hypoglycemia.