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71.
Effects of phospholipase A2 inhibitors on Ca2+ oscillations in pancreatic acinar cells 总被引:1,自引:0,他引:1
High-affinity cholecystokinin (CCK) receptors were reported to be coupled with phospholipase A2 (PLA2)-arachidonic acid (AA) pathways to mediate Ca2+ oscillations and amylase secretion in rat pancreatic acinar cells. To investigate which types of PLA2 were involved in PLA2-AA pathways, the effects of specific inhibitors for type II and type IV PLA2 on Ca2+ oscillations and amylase secretion were studied in isolated rat pancreatic acini. An inhibitor of type IV (cytosolic) PLA2, AACOCF3 inhibited Ca2+ oscillations elicited by CCK-8 (30 pM) and JMV-180 (100 nM). AACOCF3 inhibited amylase secretion stimulated by JMV-180 and low concentrations of CCK-8 (< or =30 pM). On the other hand, an inhibitor of type II (secretory, nonpancreatic) PLA2 had no effects on Ca2+ oscillations and amylase secretion stimulated by CCK-8 and JMV-180. These results suggest that high-affinity CCK receptors are coupled to cytosolic PLA2 to mediate Ca2+ oscillations and amylase secretion in rat pancreatic acinar cells. 相似文献
72.
Hiroyuki Kato Tatsushi Naganuma Yusuke Iizawa Masato Kitagawa Minoru Tanaka Shuji Isaji 《Journal of hepato-biliary-pancreatic sciences》2008,15(6):659-663
Primary lymphoma of the gallbladder is an exceedingly rare disease. We experienced an asymptomatic case of primary non-Hodgkin’s lymphoma of the gallbladder in a 55-year-old woman in whom laparoscopic cholecystectomy made a definite diagnosis. Abdominal computed tomography revealed a 4-cm gallbladder tumor with markedly enlarged lymph nodes in the retropancreatic area. Despite the marked involvement of lymph nodes, serum levels of carcinoembryonic antigen (CEA) and carbohydrate antigen (CA) 19-9 were not elevated. The discrepancy between the imaging findings and the patient’s mild clinical presentation led us to suspect that the tumor was a lymphoma. We examined serum markers of lymphoma, revealing slight elevations of interleukin (IL)-2 receptor and thymidine kinase. Laparoscopic cholecystectomy for a total biopsy was performed successfully, and the results of intraoperative frozen-section examination led us to have a high suspicion of malignant lymphoma. The final diagnosis was large diffuse B-cell lymphoma of the gallbladder with a positive CD20 antibody reaction. The patient received postoperative chemotherapy with R-CHOP (rituximab, 500 mg; cyclophosphamide, 1000 mg; adriamycin, 68 mg; vincristine, 1.9 mg; and prednisone, 80 mg) starting on postoperative day 12. She achieved complete remission and is still in complete remission 3 years and 2 months after the cholecystectomy. In conclusion, gallbladder lymphoma should be added to the differential diagnosis of gallbladder tumors, especially when the imaging findings and clinical presentation are not consistent with typical signs of gallbladder carcinoma, and laparoscopic cholecystectomy is helpful for the confirmation of suspicious cases. 相似文献
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75.
Shoichiro Hirose M.D. Hideo Honjou Hikohito Nakagawa Keigo Nishimura Yoshitaka Kuroda Masahiko Tsuji Atsuo Miwa Masanobu Kitagawa 《Journal of gastroenterology》1989,24(5):481-487
Clinical and pathological characteristics of scirrhous carcinoma of the stomach were studied in 106 cases treated by gastrectomy
between 1973 and 1983. The male to female ratio was 0.58. The percentage of scirrhous carcinomas to all gastric carcinomas
resected in the same period was three times higher in females than males. The age distribution of the patients suggested that
there were two peaks in the forties and sixties in the male, and in the thirties and fifties in the female. The incidence
of scirrhous carcinoma in all types of gastric carcinoma was significantly higher in the twenties, thirties and forties compared
to the lowest incidence in the seventies. In the female group the primary lesion had a tendency to be adjacent to the fundic
gland area and to avoid intestinal metaplasia. In the male the opposite was recognized. Cancer nests with single cells or
only several cells were common in this type of carcinoma. These findings suggest that there might be two biologically different
scirrhous carcinomas both in the male and the female, the appearance of single carcinoma cells might be favored by female
sex hormones and young ages, and not only the original gastric mucosa but also mucosa with intestinal metaplasia could be
precursors of single carcinoma cells. 相似文献
76.
Issei Tokimatsu Katsumi Shigemura Kayo Osawa Shinya Kinugawa Koichi Kitagawa Noriko Nakanishi Hiroyuki Yoshida Soichi Arakawa Masato Fujisawa 《Journal of infection and chemotherapy》2018,24(8):641-647
We conducted a nationwide molecular epidemiological study of Clostridium difficile infection (CDI) in Japan investigated the correlation between the presence of binary toxin genes and CDI severity. This is the first report on molecular epidemiological analyses for CDI in multiple university hospitals in Japan, to our knowledge. We examined 124,484 hospitalized patients in 25 national and public university hospitals in Japan between December 2013 and March 2014, investigating antimicrobial susceptibilities and toxin-related genes for C. difficile isolates from stools. Epidemiological genetic typing was performed by PCR-ribotyping and repetitive sequence-based (rep)-PCR to examine the genetic similarities. The results detected toxin A-positive, toxin B-positive, binary toxin-negative (A+B+CDT?) detected from 135 isolates (80.8%) and toxin A-negative, toxin B-positive, binary toxin-negative (A??B+CDT?) in 23 (13.8%). Toxin A-positive, toxin B-positive, and binary toxin-positive (A+B+CDT+) were seen in 9 isolates (5.4%). Vancomycin (n = 81, 37.7%) or metronidazole (n = 88, 40.9%) therapies were undertaken in analyzed cases. Ribotypes detected from isolates were 017/subgroup 1, 070, 078, 126, 176, 449, 475/subgroup 1, 499, 451, 566 and newtypes. Rep-PCR classified 167 isolates into 28 cluster groups including 2–15 isolates. In addition, 2 pairs of strains isolated from different institutions belonged to the same clusters. Seven out of 9 (77.8%) of the patients with binary toxin producing strains had “mild to moderate” outcome in evaluated symptoms. In conclusion, we found that binary toxin did not show regional specificity and had no relevance to severity of CDI. 相似文献
77.
Yoshio Takesue Shinya Kusachi Hiroshige Mikamo Junko Sato Akira Watanabe Hiroshi Kiyota Satoshi Iwata Mitsuo Kaku Hideaki Hanaki Yoshinobu Sumiyama Yuko Kitagawa Kazuhiko Nakajima Takashi Ueda Motoi Uchino Toru Mizuguchi Yoshiyasu Ambo Masafumi Konosu Keiichiro Ishibashi Katsunori Yanagihara 《Journal of infection and chemotherapy》2018,24(5):330-340
The principle of empirical therapy for patients with intra-abdominal infections (IAI) should include antibiotics with activity against Enterobacteriaceae and Bacteroides fragilis group species. Coverage of Pseudomonas aeruginosa, Enterobacter cloacae, and Enterococcus faecalis is also recommended for hospital-associated IAI. A nationwide survey was conducted to investigate the antimicrobial susceptibility of pathogens isolated from postoperative IAI. All 504 isolates were collected at 26 institutions and referred to a central laboratory for susceptibility testing. Lower susceptibility rates to ciprofloxacin and cefepime were demonstrated in Escherichia coli. Among E. coli, 24.1% of strains produced extended-spectrum β-lactamase (ESBL). Carbapenems, piperacillin/tazobactam, cephamycins/oxacephem, aminoglycosides, and tigecycline had high activity against E. coli, including ESBL-producing isolates. Among E. cloacae, low susceptibility rates to ceftazidime were demonstrated, whereas cefepime retained its activity. P. aeruginosa revealed high susceptibility rates to all antimicrobials tested except for imipenem. Among B. fragilis group species, low levels of susceptibility were observed for cefoxitin, moxifloxacin, and clindamycin, and high susceptibility rates were observed for piperacillin/tazobactam, meropenem, and metronidazole. Ampicillin, piperacillin, and glycopeptides had good activity against E. faecalis. Imipenem had the highest activity against E. faecalis among carbapenems. In conclusion, we suggested the empirical use of antimicrobials with the specific intent of covering the main organisms isolated from postoperative IAI. Piperacillin/tazobactam, meropenem, or doripenem, are appropriate in critically ill patients. Combination therapy of cefepime (aztreonam in patients with β-lactam allergy) plus metronidazole plus glycopeptides, imipenem/cilastatin or cephamycins/oxacephem plus ciprofloxacin plus metronidazole are potential therapeutic options. 相似文献
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79.
Naruse S Kitagawa M Ishiguro H Fujiki K Hayakawa T 《Best Practice & Research: Clinical Gastroenterology》2002,16(3):511-526
The discovery of the gene for cystic fibrosis (CF), the cystic fibrosis transmembrane conductance regulator (CFTR), brought about a new era in the study of this disease. Identification of the molecular target has yielded a flood of data that add to our understanding of the pathogenesis, diagnosis and treatment of CF. The CFTR protein is a cAMP-regulated Cl(-) channel with multiple functions in epithelial cells. In the exocrine pancreas the CFTR plays a key role in the apical Cl(-), HCO(3)(-), and water transport in duct cells. The severe loss of functions, caused by mutations of the CFTR gene, leads to pathological lesions of the pancreas. Over 1200 CFTR mutations and polymorphisms have been identified and their diversity may explain the high level of heterogeneity in the CF phenotype. Mutation analyses of the CFTR gene have revealed a spectrum of CFTR-related diseases that do not fit the classical CF picture but are associated with dysfunction of CFTR, such as chronic pancreatitis. 相似文献
80.
Fukui M Nakamura N Nakano K Kajiyama S Matsuo S Obayashi H Ohta M Shigeta M Shigeta H Kitagawa Y Kondo M 《Endocrine journal》2000,47(6):753-761
Proliferative response of peripheral blood mononuclear cells (PBMC) to glutamic acid decarboxylase (GAD), which has been reported in patients with type 1 diabetes, was measured in type 2 diabetes, especially in patients with antibodies to GAD initially diagnosed as having type 2 diabetes (anti-GAD+ type 2 diabetes). We studied 12 patients with type 1 diabetes, 22 with anti-GAD+ type 2 diabetes, 31 with type 2 diabetes who were negative for anti-GAD (anti-GAD+ type 2 diabetes), and 30 healthy control subjects for cellular responses in vitro to GAD. The mean stimulation index (SI) in response to GAD was significantly higher in type 1 diabetes than in anti-GAD+ type 2 diabetes or healthy controls (1.47+/-0.35 vs. 1.11+/-0.35, P<0.05, and 1.06+/-0.07, P<0.05, respectively). The mean 相似文献