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BACKGROUND: Gastric foveolar hyperplastic polyps (GFHPs) are common findings in clinical practice. GFHPs commonly arise in a background of chronic atrophic gastritis, including autoimmune gastritis (type A gastritis), and have a potential risk of malignant transformation. CASE PRESENTATION: In 2005, a 55-year-old Japanese woman underwent upper endoscopy at another hospital and was found to have a pedunculated polyp (10 mm in diameter) on the greater curvature of the lower gastric body. On biopsy, the polyp was diagnosed as a GFHP. Nine years later, the polyp had grown to 20 mm in diameter, and the biopsy specimen taken at this time showed tubular adenocarcinoma. On admission to our hospital, the serum Helicobacter Pylori (H. pylori) immunoglobulin G antibody and stool H. pylori antigen were both negative. Anti-gastric parietal cell antibody was positive, as was the anti-intrinsic factor antibody, and the fasting serum gastrin level was markedly increased. In 2014, en bloc resection of the pedunculated polyp was performed by endoscopic submucosal dissection. The final histological diagnosis was adenocarcinoma of the stomach with submucosal and lymphatic invasion. Subsequently, additional radical distal gastrectomy was performed. At the latest follow-up (12 months postoperatively), no recurrence was noted. CONCLUSIONS: We here reported a rare case of malignant transformation of GFHP arising in a context of type A gastritis. To our knowledge, there are no previous reports on malignant transformation of GFHP with submucosal and lymphatic invasion arising in a background of type A gastritis in the English literature. Further, there is currently no effective treatment other than endoscopic or surgical treatment for such cases. Given the potential risk of malignant transformation due to hypergastrinemia, we consider that endoscopic treatment should be considered as a first-line therapy when a malignant growth is suspected.
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Adenocarcinoma/patología , Pólipos Adenomatosos/patología , Transformación Celular Neoplásica/patología , Neoplasias Gástricas/patología , Estómago/patología , Adenocarcinoma/etiología , Pólipos Adenomatosos/complicaciones , Enfermedades Autoinmunes/complicaciones , Enfermedades Autoinmunes/patología , Biopsia , Femenino , Gastritis Atrófica/complicaciones , Gastritis Atrófica/patología , Gastroscopía , Helicobacter pylori , Humanos , Hiperplasia/complicaciones , Persona de Mediana Edad , Neoplasias Gástricas/complicaciones , Neoplasias Gástricas/etiologíaRESUMEN
AIM: Although recent studies indicate that supplementation with vitamin D (VD) potentiates a sustained viral response by interferon-based therapy to chronic hepatitis C, detailed mechanisms are not fully defined. The production of cathelicidin, an antimicrobial peptide, has been demonstrated to be part of the VD-dependent antimicrobial pathway in innate immunity. Cathelicidin is known to directly kill or inhibit the growth of microbial pathogens including mycobacteria and viruses. METHODS: We used a hepatitis C virus (HCV) cell culture system to clarify the anti-HCV effects of the human cathelicidin, LL-37. HuH-7 cells were administrated with LL-37 and infected with cell culture-generated HCV (HCVcc). HCV propagation was estimated by measuring the level of HCV core antigen (Ag). RESULTS: Treatment with LL-37 resulted in decreased intra- and extracellular levels of HCV core Ag, suggesting inhibition of HCV propagation. To assess the effects of LL-37 on HCV replication, JFH-1 subgenomic replicon RNA-transfected cells were treated with LL-37. However, inhibition of HCV replication was not detected by this assay. To clarify the effects on HCV infection, we treated HCVcc with LL-37 and removed the antimicrobial peptide prior to use of the virus in infection. This exposure of HCVcc to LL-37 diminished the infectivity titers in a dose-dependent fashion. Iodixanol density gradient analysis revealed that the peak fraction of infectivity titer was eliminated by LL-37 treatment. CONCLUSION: The VD-associated antimicrobial peptide LL-37 attenuated the infectivity of HCV. This anti-HCV effect of LL-37 may explain the contribution of VD to the improved efficacy of interferon-based therapy.
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AIM: The combination therapy of pegylated interferon-α and ribavirin (PEG IFN/RBV) is one of the effective treatments for chronic hepatitis C (CHC) patients. Natural killer (NK)-cell activity was reported to be impaired in patients with hepatitis C virus (HCV). The aim of this study was to examine whether PEG IFN/RBV therapy could restore NK activity in CHC patients. METHODS: In 19 CHC patients, PEG IFN/RBV therapy was performed. Just before (0M), at 3 months of the therapy (3M) and at 6 months after completion of the therapy (6M), NK activity and the frequency of NK cells, CD56(dim) NK cells and CD56(bright) NK cells in peripheral blood was estimated by creatinine release assay and flow cytometry. Statistical analysis was performed by anova and Mann-Whitney U-test. RESULTS: anova showed that NK activity significantly improved at 6M (vs 0M, P < 0.05) in the patients studied and in the patients with sustained virological response (SVR). It also showed that frequency of CD56(bright) NK cells was significantly increased at 6M (vs 0M, P < 0.05) in the patients studied and in the SVR group. However, no significant change in NK activity and frequency of CD56(bright) NK cells were detected in non-SVR group. Furthermore, NK activity ratio (6M/0M) in the SVR group was revealed to be higher compared with that in the non-SVR group by analysis using Mann-Whitney U-test (P < 0.05). CONCLUSION: PEG IFN/RBV therapy in CHC patients could improve NK activity by increasing the frequency of CD56(bright) NK cells in SVR patients. Our study also revealed that eradication of HCV could restore NK-cell activity.
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AIM: To optimize the therapeutic efficacy of NS3/4A protease inhibitors, a multicenter prospective study was performed according to an algorithm based on the Adherence, IL-28B Gene Allele and Viral Response Trial (AG & RGT). METHODS: A total of 340 patients with genotype 1b hepatitis C virus (HCV) showing serum RNA levels of >5 log were enrolled. The duration of ribavirin/pegylated interferon (PEG IFN)-α-2b therapy was prolonged to 48 weeks in patients with unfavorable IL28B alleles showing adherence rates of less than 80% for either drug during the first 12 weeks even if RVR had been achieved, and in those in whom cEVR, but not RVR, was achieved; furthermore, to 72 weeks in those showing partial early viral response. RESULTS: The therapeutic outcomes were assessed in 282 patients, and the therapy was set to complete at 24 weeks in 181 patients (64%) and to prolong to 48 weeks or 72 weeks in 71 patients (25%). The former group showed a SVR rate of 84%, while the latter group showed an SVR rate of 69% with a relapse rate of 7%. The SVR rate was 33% in the 30 patients (11%) in whom the therapy had to be discontinued in less than 12 weeks. Thus, the results of intention-to-treat analysis revealed an overall SVR rate of 75%. Multivariate analysis identified prolongation of the duration of therapy as a significant factor associated with SVR. CONCLUSION: Triple therapy yielded a high SVR rate in the AG & RGT trial via attenuation of viral relapse by prolonged ribavirin/PEG IFN-α-2b administration. © 2015 The Japan Society of Hepatology.
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BACKGROUND AND AIM: An intention-to-treat prospective randomized study was carried out to compare the potentiation of antiviral efficacies between cholecalciferol, non-activated vitamin D3 supplement, and alfacalcidol, activated 1α-Hydroxyvitamin D3 [1α (OH)-vitamin D3]. METHODS: Chronic hepatitis patients with genotype 1b hepatitis C virus (HCV) infection showing serum HCV-RNA levels greater than 5 Log IU/mL received oral administration of cholecalciferol (2000 IU/day) or alfacalcidol (0.5 µg/day) for 4 weeks, and then they were given pegylated interferon (Peg-IFN)-α2a plus ribavirin therapy in combination with either vitamin D3 for 48 or 72 weeks according to the response-guided manner. RESULTS: A total of 36 patients were evaluated. Serum 25-hydroxyvitamin D3 [25(OH)-D3] levels were increased only in patients in the cholecalciferol group during the lead-in vitamin D administration, and the levels at 4 weeks were higher in these patients than in those in the alfacalcidol group (P < 0.001), while serum 1α,25-dihydroxyvitamin D3 [1α,25(OH)2 -D3] levels were not different between both groups. Rapid virological response was obtained in six (33%) patients in the cholecalciferol group; the ratio was higher than that in the alfacalcidol group (one patient; 6%, P < 0.05). Serum HCV-RNA level decline at 4 weeks of combined Peg-IFN-α2a plus ribavirin therapy compared with the baseline levels were greater in the cholecalciferol group (4.6 Log IU/mL) than in the alfacalcidol group (3.5 Log IU/mL) (P < 0.05), when four patients showing null response to the therapy was excluded. However, both complete early virological response and sustained viral response rates were not different between both groups. CONCLUSION: Cholecalciferol produced superior potentiation of the antiviral activity than alfacalcidol only during the initial periods of combined Peg-IFN-α2a plus ribavirin therapy through upregulation of serum 25(OH)-D3 levels.
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Antivirales/administración & dosificación , Colecalciferol/administración & dosificación , Hepatitis C Crónica/tratamiento farmacológico , Hidroxicolecalciferoles/administración & dosificación , Interferón-alfa/administración & dosificación , Polietilenglicoles/administración & dosificación , Ribavirina/administración & dosificación , Administración Oftálmica , Anciano , Biomarcadores/sangre , Calcifediol/sangre , Colecalciferol/farmacología , Sinergismo Farmacológico , Quimioterapia Combinada , Femenino , Hepacivirus/genética , Hepatitis C Crónica/virología , Humanos , Hidroxicolecalciferoles/farmacología , Masculino , Persona de Mediana Edad , Estudios Prospectivos , ARN Viral/sangre , Proteínas Recombinantes/administración & dosificación , Resultado del Tratamiento , Regulación hacia Arriba/efectos de los fármacosRESUMEN
A 73-year-old woman was referred to our hospital for persistent liver dysfunction. When the patient was 45 years old, her youngest sister had been diagnosed with Wilson disease (WD). The patient therefore underwent several family screening tests, all of which were unremarkable. She had an annual medical checkup and was diagnosed with liver dysfunction and fatty liver at 68 years old. A liver biopsy and genetic testing were performed, and she was diagnosed with WD; chelation therapy was then initiated. In patients with hepatic disorders and a family history of WD, multiple medical examinations should be conducted, as the development of WD is possible regardless of age.
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Degeneración Hepatolenticular , Enfermedad del Hígado Graso no Alcohólico , Femenino , Humanos , Anciano , Persona de Mediana Edad , Degeneración Hepatolenticular/complicaciones , Degeneración Hepatolenticular/diagnóstico , Degeneración Hepatolenticular/tratamiento farmacológico , Enfermedad del Hígado Graso no Alcohólico/complicaciones , Enfermedad del Hígado Graso no Alcohólico/diagnóstico , Pruebas Genéticas , Cobre , PacientesRESUMEN
Hepatitis C virus (HCV), a member of the Flaviviridae family, is a single-stranded positive-sense RNA virus that infects >170 million people worldwide and causes acute and chronic hepatitis, cirrhosis, and hepatocellular carcinoma. Despite its ability to block the innate host response in infected hepatocyte cell lines in vitro, HCV induces a strong type 1 interferon (IFN) response in the infected liver. The source of IFN in vivo and how it is induced are currently undefined. Here we report that HCV-infected cells trigger a robust IFN response in plasmacytoid dendritic cells (pDCs) by a mechanism that requires active viral replication, direct cell-cell contact, and Toll-like receptor 7 signaling, and we show that the activated pDC supernatant inhibits HCV infection in an IFN receptor-dependent manner. Importantly, the same events are triggered by HCV subgenomic replicon cells but not by free virus particles, suggesting the existence of a novel cell-cell RNA transfer process whereby HCV-infected cells can activate pDCs to produce IFN without infecting them. These results may explain how HCV induces IFN production in the liver, and they reveal a heretofore unsuspected aspect of the innate host response to viruses that can subvert the classical sensing machinery in the cells they infect, and do not infect or directly activate pDCs.
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Células Dendríticas/citología , Células Dendríticas/virología , Hepacivirus/metabolismo , Interferones/metabolismo , Línea Celular , Técnicas de Cocultivo , Ensayo de Inmunoadsorción Enzimática , Células HeLa , Hepatocitos/virología , Humanos , Inmunidad Innata , Cinética , ARN/metabolismo , Transducción de Señal , Receptores Toll-Like/metabolismo , Replicación ViralRESUMEN
Most cases of liver dysfunction in pregnancy are pregnancy-related, but the onset of systemic autoimmune diseases is also differentiated. A 24-year-old woman presented with liver dysfunction at 28 weeks' gestation with suspected autoimmune hepatitis and started taking ursodeoxycholic acid. She gave birth prematurely at 35 weeks' gestation, and the infant presented with pancytopenia and liver failure but survived because of liver transplantation. Since the patient had major symptoms during the puerperium, she was diagnosed with adult-onset Still's disease. When encountering a patient with liver dysfunction during pregnancy, we should also consider the onset of autoimmune diseases.
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Hepatitis Autoinmune , Fallo Hepático , Trasplante de Hígado , Enfermedad de Still del Adulto , Adulto , Femenino , Embarazo , Lactante , Humanos , Adulto Joven , Enfermedad de Still del Adulto/complicaciones , Enfermedad de Still del Adulto/diagnóstico , Fallo Hepático/diagnóstico , Fallo Hepático/etiología , Periodo Posparto , Hepatitis Autoinmune/complicaciones , Hepatitis Autoinmune/diagnósticoRESUMEN
A 78-year-old man with hepatocellular carcinoma treated by chemoembolization and percutaneous ethanol injection was admitted to our hospital because of acute abdomen. The CT scan showed biliary fistula caused by hepatocellular carcinoma protruding from S3. Endoscopic retrograde cholangiopancreatography showed disruption of an intrahepatic duct and the main pancreatic duct, and contrast agent leaked into the peritoneal cavity from each duct. Omental panniculitis with biliary fistula and pancreatic fistula was diagnosed. The symptoms improved by endoscopic nasobiliary drainage and endoscopic pancreatic stenting. On the 13th day after admission, we added endoscopic nasopancreatic drainage because his abdominal pain had been exacerbated by pancreatic juice leakage. Omental panniculitis by hepatocellular carcinoma complicated by biliary fistula and pancreatic fistula is extremely rare. Endoscopic transpapillary pancreaticobiliary drainage was effective for omental panniculitis in this case.
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Fístula Biliar/complicaciones , Carcinoma Hepatocelular/complicaciones , Drenaje/métodos , Endoscopía del Sistema Digestivo , Neoplasias Hepáticas/complicaciones , Fístula Pancreática/complicaciones , Paniculitis Peritoneal/cirugía , Anciano , Humanos , Masculino , Paniculitis Peritoneal/etiologíaRESUMEN
Pruritus is known to be a common complication in hepatitis patients, but the exact frequency and degree are not fully elucidated. Thus, we evaluated pruritus of 450 patients with chronic liver disease at our hospital. Pruritus was observed in 240 (53%) of the patients. Pruritus was significantly associated with males (OR = 1.51, P = 0.038) and patients with alkaline phosphatase (ALP) ≥ 200 U/L (OR = 1.56, P = 0.0495) and was significantly less in HBsAg-positive patients (OR = 0.449, P = 0.004). Seasonally, there was no difference in the frequency of pruritus between summer and winter. Of the 24 refractory pruritus patients treated with nalfurafine, 17 (71%) indicated improvement of itch, which is defined as a decrease in the visual analog scale score ≥ 30 mm. Pruritus was improved by nalfurafine both during daytime and nighttime in the Kawashima's scores evaluation. All patients who received nalfurafine exhibited improved Kawashima's scores ≥ 1 point during the daytime or nighttime. In conclusion, pruritus occurred in > 50% of patients with chronic liver disease, and predictors of pruritus were males and ALP ≥ 200 U/L. Nalfurafine may be useful for pruritus, regardless of whether daytime or nighttime.
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Enfermedad Hepática en Estado Terminal/tratamiento farmacológico , Morfinanos/administración & dosificación , Prurito/tratamiento farmacológico , Compuestos de Espiro/administración & dosificación , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Enfermedad Hepática en Estado Terminal/complicaciones , Enfermedad Hepática en Estado Terminal/genética , Enfermedad Hepática en Estado Terminal/patología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Prurito/complicaciones , Prurito/patología , Resultado del Tratamiento , Adulto JovenRESUMEN
The impact of virus dose on the outcome of infection is poorly understood. In this study we show that, for hepatitis B virus (HBV), the size of the inoculum contributes to the kinetics of viral spread and immunological priming, which then determine the outcome of infection. Adult chimpanzees were infected with a serially diluted monoclonal HBV inoculum. Unexpectedly, despite vastly different viral kinetics, both high-dose inocula (10(10) genome equivalents [GE] per animal) and low-dose inocula (10 degrees GE per animal) primed the CD4 T-cell response after logarithmic spread was detectable, allowing infection of 100% of hepatocytes and requiring prolonged immunopathology before clearance occurred. In contrast, intermediate (10(7) and 10(4) GE) inocula primed the T-cell response before detectable logarithmic spread and were abruptly terminated with minimal immunopathology before 0.1% of hepatocytes were infected. Surprisingly, a dosage of 10(1) GE primed the T-cell response after all hepatocytes were infected and caused either prolonged or persistent infection with severe immunopathology. Finally, CD4 T-cell depletion before inoculation of a normally rapidly controlled inoculum precluded T-cell priming and caused persistent infection with minimal immunopathology. These results suggest that the relationship between the kinetics of viral spread and CD4 T-cell priming determines the outcome of HBV infection.
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Virus de la Hepatitis B/metabolismo , Hepatitis B/virología , Animales , Linfocitos T CD4-Positivos/virología , ADN Viral/metabolismo , Citometría de Flujo/métodos , Virus de la Hepatitis B/patogenicidad , Hepatocitos/virología , Interferón gamma/metabolismo , Cinética , Leucocitos Mononucleares/virología , Hígado/virología , Pan troglodytesRESUMEN
A 47-year-old man presented with an abnormality of the duodenum detected on a health check endoscopy. Further endoscopy revealed swelling of the papilla of Vater with a whitish exudate and surrounding small nodules, which biopsy revealed to be non-caseating granulomas. Colonoscopy showed typical tubercular lesions in the colon on the right side, so we speculated that the lesions of the papilla of Vater were tubercular. After the administration of anti-tubercular drugs, both the duodenal lesion and the colonic lesions improved. Therefore, the papilla of Vater lesion was diagnosed as tubercular, although such cases are extremely rare.
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Ampolla Hepatopancreática , Colangitis/diagnóstico , Duodenitis/diagnóstico , Tuberculosis Gastrointestinal/diagnóstico , Tuberculosis/diagnóstico , Humanos , Masculino , Persona de Mediana EdadRESUMEN
An 83-year-old man with a history of carbon ion radiotherapy for hepatocellular carcinoma nine years ago presented to a primary care hospital with a fever and abdominal pain. He underwent computed tomography, which revealed the rupture of a hepatic pseudoaneurysm close to the fiducial marker for carbon ion radiotherapy and bleeding into the bile duct. He was successfully treated with transcatheter arterial embolization. Thereafter, re-rupture occurred from a site proximal to the first rupture, and this was treated similarly. It is necessary to be alert for not only tumor recurrence but also pseudoaneurysm occurrence after carbon ion radiotherapy.
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Aneurisma Falso/terapia , Carcinoma Hepatocelular/patología , Embolización Terapéutica/métodos , Neoplasias Hepáticas/patología , Rotura Espontánea/terapia , Anciano de 80 o más Años , Humanos , Masculino , Recurrencia , Resultado del TratamientoAsunto(s)
Enfermedad de Still del Adulto , Humanos , Femenino , Embarazo , Enfermedad de Still del Adulto/diagnóstico , Enfermedad de Still del Adulto/complicaciones , Adulto , Periodo Posparto , Fallo Hepático/etiología , Fallo Hepático/diagnóstico , Complicaciones del Embarazo/diagnóstico , Recién NacidoRESUMEN
Dendritic cells (DCs) are potent antigen-presenting cells, which have recently been applied for cancer immunotherapy using epitope peptides. Accumulating results of the clinical trials of such a strategy suggest that maturity of the applied DCs has a significant impact on the outcome of the vaccination. Here we examined the effects of penicillin-killed Streptococcus pyogenes (OK-432) on DC maturation and functions including induction of CTLs. DCs generated from peripheral blood using granulocyte macrophage colony-stimulating factor and interleukin (IL)-4 showed immunophenotypes consistent with immature DCs (iDCs). These iDCs were further incubated with medium alone, tumor necrosis factor alpha, lipopolysaccharide, or OK-432. The immunophenotypical analysis showed DCs stimulated with OK-432 (OK-DCs) possessed significantly higher expression of CD83 compared with unstimulated DCs. Furthermore, OK-DCs showed significantly higher production of IL-12 and IFN-gamma compared with DCs with other stimulations. These results indicate that OK-432 stimulates iDCs to have a mature phenotype and to produce a significant amount of T-helper 1-type cytokines. To examine the potency of OK-DCs on the induction of specific CTLs, the tumor rejection peptide derived from carcinoembryonic antigen was used as a model antigen. The HLA-tetramer assay showed that potent CTL was induced with OK-DCs at high frequency. These results indicate that OK-432 efficiently stimulates DCs without interfering with the presentation of pulsed peptide. Furthermore, OK-432 does not activate nuclear factor kappaB through Toll-like receptor 2 or Toll-like receptor 4 in the indicator cell system; however, it induces IL-12 production through the beta(2) integrin system on DCs. These results strongly suggest that OK-432 could be applied to develop an efficient cancer vaccine using DCs pulsed with tumor rejection peptides.
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Células Dendríticas/inmunología , Picibanil/farmacología , Linfocitos T Citotóxicos/inmunología , Antígenos CD18/metabolismo , Células Dendríticas/efectos de los fármacos , Células Dendríticas/metabolismo , Epítopos de Linfocito T/inmunología , Humanos , Interferón gamma/biosíntesis , Interferón gamma/metabolismo , Interleucina-10/biosíntesis , Interleucina-12/biosíntesis , Interleucina-12/metabolismo , Glicoproteínas de Membrana/inmunología , Glicoproteínas de Membrana/metabolismo , Receptores de Superficie Celular/inmunología , Receptores de Superficie Celular/metabolismo , Transducción de Señal , Receptor Toll-Like 2 , Receptor Toll-Like 4 , Receptores Toll-LikeAsunto(s)
Antineoplásicos/uso terapéutico , Carcinoma Hepatocelular/tratamiento farmacológico , Neoplasias Hepáticas/tratamiento farmacológico , Sorafenib/uso terapéutico , Carcinoma Hepatocelular/patología , Humanos , Neoplasias Hepáticas/patología , Niacinamida , Compuestos de Fenilurea , Rotura , Resultado del TratamientoRESUMEN
AIM: To elucidate the characteristics of hemorrhagic gastric/duodenal ulcers in a post-earthquake period within one medical district. METHODS: Hemorrhagic gastric/duodenal ulcers in the Iwate Prefectural Kamaishi Hospital during the 6-mo period after the Great East Japan Earthquake Disaster were reviewed retrospectively. The subjects were 27 patients who visited our hospital with a chief complaint of hematemesis or hemorrhagic stool and were diagnosed as having hemorrhagic gastric/duodenal ulcers by upper gastrointestinal endoscopy during a 6-mo period starting on March 11, 2011. This period was divided into two phases: the acute stress phase, comprising the first month after the earthquake disaster, and the chronic stress phase, from the second through the sixth month. The following items were analyzed according to these phases: age, sex, sites and number of ulcers, peptic ulcer history, status of Helicobacter pylori (H. pylori) infection, intake of non-steroidal anti-inflammatory drugs, and degree of impact of the earthquake disaster. RESULTS: In the acute stress phase from 10 d to 1 mo after the disaster, the number of patients increased rapidly, with a nearly equal male-to-female ratio, and the rate of multiple ulcers was significantly higher than in the previous year (88.9% vs 25%, P < 0.005). In the chronic stress phase starting 1 mo after the earthquake disaster, the number of patients decreased to a level similar to that of the previous year. There were more male patients during this period, and many patients tended to have a solitary ulcer. All patients with duodenal ulcers found in the acute stress phase were negative for serum H. pylori antibodies, and this was significantly different from the previous year's positive rate of 75% (P < 0.05). CONCLUSION: Severe stress caused by an earthquake disaster may have affected the characteristics of hemorrhagic gastric/duodenal ulcers.
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Desastres , Úlcera Duodenal/epidemiología , Terremotos , Úlcera Péptica Hemorrágica/epidemiología , Úlcera Gástrica/epidemiología , Adulto , Anciano , Anciano de 80 o más Años , Antiinflamatorios no Esteroideos/efectos adversos , Enfermedad Crónica , Úlcera Duodenal/diagnóstico , Endoscopía Gastrointestinal , Femenino , Infecciones por Helicobacter/diagnóstico , Infecciones por Helicobacter/epidemiología , Infecciones por Helicobacter/microbiología , Humanos , Incidencia , Japón/epidemiología , Masculino , Persona de Mediana Edad , Úlcera Péptica Hemorrágica/diagnóstico , Pronóstico , Estudios Retrospectivos , Factores de Riesgo , Úlcera Gástrica/diagnóstico , Estrés Psicológico/diagnóstico , Estrés Psicológico/epidemiología , Factores de TiempoRESUMEN
Chimpanzees represent important models for studying several human pathogens. In the present study, we utilized a combinatorial peptide library to characterize the binding specificities of the chimpanzee class I molecules Patr A 0301 and A 0401, both of which are present in about 17% of chimpanzees. Patr A 0301 was found to recognize peptides using the canonical position 2/C-terminus spacing, with the small residues S, T, and A being the most preferred in position 2, and the positively charged residues R and K preferred at the C terminus. Patr A 0401 was found to recognize a more complex motif where the C terminus and then the residue in positions 1 and/or 5 are the primary anchors. Like A 0301, the C-terminal preference of A 0401 is for positively charged residues. At positions 1 and 5, positively charged and large residues are the most preferred, respectively. Coefficient values derived from the combinatorial library proved to be an efficient means for predicting A 0301 and A 0401 binders. The present data provide detailed information to facilitate the identification of potential T cell epitopes recognized in the context of two common chimpanzee class I alleles, and further validate the combinatorial library approach as an efficient method to characterize class I binding specificities.
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Antígenos de Histocompatibilidad Clase I/inmunología , Pan troglodytes/inmunología , Biblioteca de Péptidos , Alelos , Animales , Antígenos de Histocompatibilidad Clase I/genética , Unión ProteicaRESUMEN
The chimpanzee (Pan troglodytes) is an important model for studying the immune response to several human pathogens, but the study of correlates of immunity has been hindered by the fact that little is known about the epitope-binding specificity of chimpanzee (Patr) class I MHC. In the present study we have characterized the peptide binding specificity of several common Patr class I molecules. Using single amino acid substitution analogs and large peptide libraries, quantitative peptide binding motifs have been derived for Patr A*0101, A*0701, A*0901, B*0101, and B*2401. Each molecule was found to bind peptides using position 2 and the C terminus as main anchor contacts. On the other hand, each Patr molecule is associated with a unique binding specificity, and the range of specificities is similar to that seen amongst HLA alleles. A high degree of cross-reactivity was noted between Patr A*0701 and Patr A*0901, suggesting the existence of a Patr-specific supertype. Consistent with previous studies suggesting that some cross-reactivity may exist between HLA and Patr alleles, Patr A*0901 was found to have an appreciable degree of cross-reactivity with molecules of the HLA A24-supertype. Finally, utilizing motif scans and peptide binding and intracellular cytokine staining assays, 77 hepatitis B virus (HBV)-derived epitopes were identified in five chimpanzees that were recently convalescent from acute HBV infection. Because the Patr alleles studied herein were found to be very common in two different chimpanzee populations, the present data should facilitate the use of chimpanzees for immunological studies.
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Antígenos de Histocompatibilidad Clase I/inmunología , Epítopos Inmunodominantes/inmunología , Modelos Animales , Pan troglodytes/inmunología , Péptidos/inmunología , Secuencias de Aminoácidos , Secuencia de Aminoácidos , Sustitución de Aminoácidos , Animales , Reacciones Cruzadas , Antígenos HLA-A/genética , Antígenos HLA-A/inmunología , Antígenos de la Hepatitis B/inmunología , Antígenos de Histocompatibilidad Clase I/genética , Humanos , Epítopos Inmunodominantes/genética , Datos de Secuencia Molecular , Pan troglodytes/genética , Biblioteca de Péptidos , Péptidos/genéticaRESUMEN
When TT virus (TTV) DNA was quantitated in whole blood and plasma aliquots from 27 viremic individuals by real-time detection PCR that can detect essentially all TTV genotypes, the TTV load was 6.9 +/- 3.5 (mean +/- standard deviation)-fold higher in the whole blood than in the plasma samples [P < 0.002 (paired t test)]. To clarify the reason for this difference, peripheral blood cells of various types including red blood cells, granulocytes (CD15+), B cells (CD19+), T cells (CD3+), monocytes (CD14+), and NK cells (CD3-/CD56+) were separated at a purity of 95.4-99.5% from each of three infected individuals with relatively high TTV viremia, and their TTV viral loads were determined. Red blood cells were uniformly negative, but the other cell types were positive for TTV DNA at various titers. In all three patients, the highest TTV load was found in granulocytes (4.2 x 10(4)-3.1 x 10(5) copies/10(6) cells), followed by monocytes (1.4-2.2 x 10(4) copies/10(6) cells) and NK cells (5.4-6.5 x 10(3) copies/10(6) cells); B and T cells were positive, with a low viral load (6.7 x 10(1)-2.7 x 10(3) copies/10(6) cells). These results indicate that TTV is distributed in various peripheral blood cell types at distinct levels, with the highest viral load in granulocytes, and that a significant proportion of the TTV DNA in peripheral blood is not identified by the standard plasma/serum DNA detection methods.