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11.
Eye infections caused by adenovirus (Ad) often result in nosocomial infections and community epidemics with significant rates of morbidity. No antiviral agent effective against Ad is yet available for clinical use. Therefore, early diagnosis is still the mainstay for patient management and the prevention of epidemics. A multiplex PCR assay based on amplification of a combination of the fiber and hexon genes which can identify the six important oculopathogenic serotypes of Ads (Ad serotype 3[Ad3], Ad4, Ad7, Ad8, Ad19, and Ad37) in a single-tube amplification reaction was developed. Ad serotypes could be distinguished by the different amplicon sizes. The assay correctly identified prototype strains as well as isolates in clinical specimens. In comparison with a previously described PCR-restriction fragment polymorphism method, our assay gave unequivocal results for clinical specimens. Our multiplex PCR has the potential to serve as a rapid and cost-effective tool for the typing of important ocular Ads. 相似文献
12.
Morita Y Ujike H Tanaka Y Uchida N Nomura A Ohtani K Kishimoto M Morio A Imamura T Sakai A Inada T Harano M Komiyama T Yamada M Sekine Y Iwata N Iyo M Sora I Ozaki N Kuroda S 《Neuroscience letters》2005,376(3):182-187
Genetic contributions to the etiology of substance abuse and dependence are topics of major interest. Acute and chronic cannabis use can produce drug-induced psychosis resembling schizophrenia and worsen positive symptoms of schizophrenia. The endocannabinoid system is one of the most important neural signaling pathways implicated in substance abuse and dependence. The fatty acid amide hydrolase (FAAH) is a primary catabolic enzyme of endocannabinoids. To clarify a possible involvement of FAAH in the etiology of methamphetamine dependence/psychosis or schizophrenia, we examined the genetic association of a nonsynonymous polymorphism of the FAAH gene (Pro129Thr) by a case-control study. We found no significant association in allele and genotype frequencies of the polymorphism with either disorder. Because the Pro129Thr polymorphism reduces enzyme instability, it is unlikely that dysfunction of FAAH and enhanced endocannabinoid system induce susceptibility to either methamphetamine dependence/psychosis or schizophrenia. 相似文献
13.
M. Kohmoto T. Miyazawa E. Sato K. Uetsuka Y. Nishimura Y. Ikeda G. Inada K. Doi T. Mikami 《Archives of virology》1998,143(9):1839-1845
Summary. Following establishment, via the vaginal route, of infection with an AP-1 binding-site deleted mutant (ΔAP-1) of feline immunodeficiency
virus (FIV), cats were challenged with a homologous intact strain (TM2) of FIV. The cats were observed for 23 weeks to evaluate
the efficacy of the ΔAP-1 against the homologous TM2 strain challenge. These two viruses were differentiated by Southern blotting
after amplification of proviral DNA by semi-nested polymerase chain reaction in DNAs of peripheral blood mononuclear cells
and tissues. A TM2-specific band was detected in one cat exposed to but not infected with ΔAP-1, but not in two ΔAP-1-infected.
These results indicate that ΔAP-1 could protect against subsequent challenge with homologous FIV TM2 strain.
Received December 23, 1998 Accepted March 31, 1998 相似文献
14.
Akari Inada Cameron Nienaber Sonya Fonseca Susan Bonner-Weir 《Developmental dynamics》2006,235(6):1571-1577
In the search for genetic markers for assessing the role of duct cells in pancreas growth, we examined whether carbonic anhydrase II (CAII) has ductal cell specificity. We determined the distribution and timing of CAII expression in mouse pancreas from embryonic stage to adult. The pancreatic ducts only start expressing CAII at embryonic day (E) 18.5, with increases after birth. Around E15.5, glucagon-positive cells, but not insulin-positive cells, also express CAII, with further increases by adult. CAII expression was restricted to cells within ductal structures and glucagon-positive cells with no colocalization with any insulin-positive cells at any time. In the human pancreas, CAII expression is restricted to the ducts. Furthermore, the activity of a 1.6-kb fragment of the human promoter with Luciferase assays was moderately strong compared with the cytomegalovirus promoter in human pancreatic duct cell line (PANC-1). Thus, we believe that the CAII gene could serve as a useful pancreatic duct cell marker. 相似文献
15.
M Murakoshi R Inada M Tagawa M Makino M Suzuki M Mieda S Honma Y Takezawa H Yamanaka 《Acta pathologica japonica》1992,42(3):151-157
The effect of a synthetic steroidal anti-androgen, TZP-4238, on spontaneous benign prostatic hyperplasia (BPH) in dogs was investigated. Old male beagle dogs (5-9 years old) were divided into three experimental groups. Group 1 consisted of BPH controls. Groups 2 and 3 received TZP-4238 0.1 mg/kg/day and chlormadinone acetate (CMA) 0.3 mg/kg/day p.o., respectively, for 5 months. In group 1, glandular hyperplasia of the prostate was clearly detected. In contrast, TZP-4238 (Group 2) or CMA (Group 3) produced marked atrophy of the glandular epithelium. In addition, a histopathological study showed that TZP-4238 or CMA medication for 5 months exerted no effect on the testes and the pituitary luteinizing hormone (LH) cells. Therefore, it is suggested that TZP-4238 (0.1 mg/kg) or CMA (0.3 mg/kg) causes regression of spontaneous canine BPH without any histopathological effects on the testes and pituitary LH cells. However, slightly decreased serum testosterone levels were found in TZP-4238-treated animals, due apparently to a direct and/or indirect effect on the testes. Thus, it is suggested that a marginal antigonadotrophic effect cannot be excluded. It is concluded that TZP-4238 is a potent anti-androgen for the treatment of spontaneous canine BPH, without any negative influence on the function of the testes and the pituitary LH cells. 相似文献
16.
Determinants of activation by complement of group II phospholipase A2 acting against Escherichia coli. 总被引:1,自引:0,他引:1
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Prompt killing of many strains of Escherichia coli during phagocytosis in vitro by isolated polymorphonuclear leukocytes (PMN) requires the presence of nonlethal doses of nonimmune serum (B. A. Mannion, J. Weiss, and P. Elsbach, J. Clin. Invest. 86:631-641, 1990). Because this requirement is bypassed in a phospholipase A (PLA)-rich mutant (pldA ) of E. coli, we have examined the effect of serum on bacteria] phospholipid (PL) degradation during phagocytosis of wild-type (pldA+) and PLA-deficient (pldA) E. coli. In parallel with increased killing, nonlethal doses of serum increased the degradation of prelabeled bacterial PL during phagocytosis by two- to fivefold, to nearly the same levels (ca. 50 to 60%) as those produced during phagocytosis of E. coli pldA in the absence of serum. The effects on the E. coli pldA mutant imply that there is a serum-mediated enhancement of granule-associated group II PMN PLA2 activity. At the same doses, serum promoted action against E. coli in the presence of purified rabbit and human group II PLA2 but did not activate bacterial PLA. Related PLA2s that lack specific structural determinants needed for optimal activity against E. coli treated with the bactericidal/permeability-increasing protein (BPI) of PMN are also less active than wild-type group II PLA2 against serum-treated E. coli. Treatment of E. coli with C7- or C9-depleted serum did not enhance bacterial killing or PL degradation during phagocytosis or the action of purified PLA2. In summary, these findings suggest that (i) nonlethal assemblies of the membrane attack complex promote intracellular killing and destruction of E. coli ingested by PMN, in part by promoting the action of granule-associated PLA2 against ingested bacteria, and (ii) structural determinants first implicated in PLA2 action against BPI-treated E. coli are also important in PLA2 action in concert with other host defense systems, such as complement. 相似文献
17.
Endo S Inoue Y Fujino Y Yamada Y Sato N Wakabayashi G Sakamoto T Ishikura H Tanaka T Inada K Sato S 《Research communications in molecular pathology and pharmacology》2000,108(3-4):179-186
The FasL-Fas system is an apoptosis induction system and plays an important role in homeostasis and biophylaxis. The present study was conducted to investigate soluble Fas (sFas), soluble Fas ligand (sFasL), and tumor necrosis factor alpha (TNF-alpha) in patients with acute pancreatitis. As acute pancreatitis became severe, the levels of sFas in the serum increased significantly, while those of sFasL decreased significantly. A significant inverse correlation was observed between the serum levels of sFas and those of sFasL. Also, a significant positive correlation was observed between the levels of TNF-alpha and sFas. A greater increase in serum sFas and decrease in serum sFasL levels was observed in patients with complicating multiple organ dysfunction syndrome (MODS) than in those without it. The results of the study suggest that the pathological aggravation of acute pancreatitis could be related to changes in the Fas-FasL system. 相似文献
18.
Recently developed immunohistochemical techniques are revolutionizing surgical pathology. Although much has been written describing sensitivity and specificity of reagents in the relationship to given diagnoses, little has been published regarding the evaluation in diagnostic histopathology. Of 4905 cases, immunohistochemical stains were done in our laboratory on 108 cases in 1988. Forty three markers of different kinds were used for 266 specimens. The mean number of markers used in one case was 2.5. Evaluation study of these cases revealed good to limited diagnostic value of immunohistochemical procedures in about 70% of those cases, but no diagnostic value in approximately 30% of the cases. Relationship between venous invasion and basement membrane was investigated to clarify the mechanism of liver metastasis of the colorectal carcinoma by histologically and immunohistochemically using the anti-laminin antibody. Ninety cases of colorectal carcinoma with liver metastasis were studied. Venous invasion was found in 60 of 66 cases of synchronous liver metastasis, and in 14 of 24 cases of metachronous liver metastasis. Venous invasion was considered highly significant to development of liver metastasis, though there was a definite difference in several aspects between the two groups. Well-defined laminin-containing basement membrane was found in the primary tumor in 35 of 90 cases and in metastatic foci in 15 of 28 cases in which examination was performed. It was most frequently seen in well differentiated adenocarcinoma, though statistically not significant compared to moderately differentiated adenocarcinoma. No definite correlation was found between development of liver metastasis and basement membrane associated tumor cells. 相似文献
19.
Fujioka H Okano Y Inada H Asada M Kawamura T Hase Y Yamano T 《European journal of human genetics : EJHG》2001,9(12):931-937
Congenital hyperinsulinism and hyperammonaemia (CHH) is caused by dysregulation of glutamate dehydrogenase (GDH). We characterised the GDH gene in two Japanese patients with CHH. Patient 1 showed late-onset and mild hypoglycaemic episodes and mild hyperammonaemia, compared with patient 2. In GDH activity of lymphoblasts, patient 1 showed twofold higher basal GDH activity than control subjects and mild insensitivity for GTP inhibition. Patient 2 showed severe insensitivity for GTP inhibition, and similar allosteric stimulation by ADP in the controls. Genetic studies identified heterozygous and de novo L413V and G446D mutations in patients 1 and 2, respectively. COS cell expression study confirmed that both mutations were disease-causing gene. The insensitivity for GTP inhibition in L413V and G446D was emphasised in COS cell expression system as a result of the dosage effect of mutant GDH gene. L413V showed less impairment of GDH than G446D based on biochemical and genetic results, which was consistent with the clinical phenotype. Based on the structure of bovine GDH, G446D was located in GTP binding site of pivot helix and its surroundings, while L413V was located in alpha-helix of antenna-like structure. These different locations of mutations gave different effects on GDH enzyme. The antenna-like structure plays an important role in GDH activity. 相似文献
20.
Kamoshida S Matsuoka H Shiogama K Matsuyama A Shimomura R Inada K Maruta M Tsutsumi Y 《Pathology international》2004,54(8):564-575
High expression of thymidylate synthase (TS) is allegedly associated with the chemoresistance to 5-fluorouracil (5-FU) in colorectal cancers. However, low TS expression does not necessarily imply chemosensitivity. Inactivation of p16(INK4a) correlates with poor prognosis in various cancers. We immunohistochemically evaluated the relationship between the expression of TS, p16(INK4a), CDK4 and cyclin D1 and the effect of 5-FU-based chemotherapy in colorectal cancers. After antigen retrieval, immunoperoxidase staining was performed on the paraffin-embedded, biopsy and surgical specimens of 37 advanced colorectal cancers preoperatively treated with peroral administration of 5-FU derivatives. As a control group, 31 colorectal cancers without preoperative treatment were analyzed. High TS expression was found in 23 (74%) of 31 tumors resected from histological non-responders and in 19 (61%) of 31 controls but in none of six responders. High p16(INK4a) expression was seen in 83% of the responders, 52% of the non-responders and 32% of the controls. The TS-low/p16(INK4a)-high phenotype was noted in 83% of the responders, but only in 3% of the non-responders (P = 0.0001). Induction of p16(INK4a) expression after chemotherapy was predominantly seen in the responders. Neither CDK4 nor cyclin D1 expression was related to the chemotherapeutic effects. In conclusion, the combination of low expression of TS and induction of p16(INK4a) after chemotherapy can be important indicators of the sensitivity to 5-FU-based chemotherapy in colorectal cancers. 相似文献