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91.
Two closely related ubiquitin C-terminal hydrolase isozymes function as reciprocal modulators of germ cell apoptosis in cryptorchid testis 下载免费PDF全文
Kwon J Wang YL Setsuie R Sekiguchi S Sato Y Sakurai M Noda M Aoki S Yoshikawa Y Wada K 《The American journal of pathology》2004,165(4):1367-1374
The experimentally induced cryptorchid mouse model is useful for elucidating the in vivo molecular mechanism of germ cell apoptosis. Apoptosis, in general, is thought to be partly regulated by the ubiquitin-proteasome system. Here, we analyzed the function of two closely related members of the ubiquitin C-terminal hydrolase (UCH) family in testicular germ cell apoptosis experimentally induced by cryptorchidism. The two enzymes, UCH-L1 and UCH-L3, deubiquitinate ubiquitin-protein conjugates and control the cellular balance of ubiquitin. The testes of gracile axonal dystrophy (gad) mice, which lack UCH-L1, were resistant to cryptorchid stress-related injury and had reduced ubiquitin levels. The level of both anti-apoptotic (Bcl-2 family and XIAP) and prosurvival (pCREB and BDNF) proteins was significantly higher in gad mice after cryptorchid stress. In contrast, Uchl3 knockout mice showed profound testicular atrophy and apoptotic germ cell loss after cryptorchid injury. Ubiquitin level was not significantly different between wild-type and Uchl3 knockout mice, whereas the levels of Nedd8 and the apoptotic proteins p53, Bax, and caspase3 were elevated in Uchl3 knockout mice. These results demonstrate that UCH-L1 and UCH-L3 function differentially to regulate the cellular levels of anti-apoptotic, prosurvival, and apoptotic proteins during testicular germ cell apoptosis. 相似文献
92.
Recently, genomic DNA of the novel TT virus (TTV) was isolated from patients suffering from posttransfusion hepatitis of unknown etiology. We examined sera from 197 children who visited the Department of Pediatrics at Toyohashi National Hospital. Sera were tested for TTV DNA by seminested polymerase chain reaction (PCR) using a set of primers synthesized according to the published TTV sequence. Ten children were found to be positive for TTV (5.1%). All positive PCR products were directly sequenced in both directions using a fluorescent dye terminator cycle sequencing system. The sequences were compared by a multiple sequence alignment and a phylogenetic tree was constructed. The phylogenetic tree showed that two of the TTV isolates found in the present experiment did not belong to any of the phylogenetic groups previously reported. 相似文献
93.
Shinichi Shimizu Hiroshi Kobayashi Hisashi Watanabe Yoshihisa Ohnishi 《Pathology international》1986,36(1):105-112
Mallory body-like structures (MBLs), which resemble Mallory body (MB) in the liver, were observed in lungs of 4 cases showing interstitial pneumonitis. MBLs were found in the cytoplasm of especially swollen alveolar epithelial cells. MBLs and MBs had almost similar characteristics morphologically and tinctorially under the light microscopy. MBLs were composed of intermediate type fine fibrils which were positive for anti-keratin antibody. These findings suggested that MBLs were a kind of pathological keratinization of alveolar epithelial cells. Although the origin of MBL containing cells could not be clarified, they were closely related to type 2 alveolar epithelial cells. 相似文献
94.
Effects of bilobalide, a sesquiterpene in Ginkgo biloba leaves, on population spikes in rat hippocampal slices 总被引:1,自引:0,他引:1
Sasaki K Oota I Wada K Inomata K Ohshika H Haga M 《Comparative biochemistry and physiology. Part C, Pharmacology, toxicology & endocrinology》1999,124(3):315-321
The effects of bilobalide, a sesquiterpene isolated from the leaves of Ginkgo biloba L., were investigated in a rat hippocampal slice preparation. Bilobalide (10-500 microM) significantly increased the amplitude of population spikes evoked by electrical stimulation of Schaffer collateral/commissural fibers in a concentration-dependent manner. Paired-pulse inhibition at interpulse intervals of 10-50 ms was significantly reduced in the presence of bilobalide (50 microM). The inhibitory action of muscimol (1 microM) was attenuated by bilobalide (100 microM). These results suggest that bilobalide induces an enhancement of excitability of CA1 pyramidal neurons, which involves, at least in part, a reduction in GABAergic inhibition in rat hippocampus. 相似文献
95.
Identification of ligand recognition sites in heat-stable enterotoxin receptor, membrane-associated guanylyl cyclase C by site-directed mutational analysis. 下载免费PDF全文
A Wada T Hirayama H Kitaura J Fujisawa M Hasegawa Y Hidaka Y Shimonishi 《Infection and immunity》1996,64(12):5144-5150
Guanylyl cyclase C (STaR), a receptor protein for heat-stable enterotoxin (STa) elaborated by Escherichia coli, is associated with and spans the plasma membrane of mammalian intestinal cells. The extracellular domain functions in the binding of STa and the association of each domain to an oligomeric form. Two amino acid residues, Arg-136 and Asp-347, were identified as the residues binding to STa in the extracellular domain of pig STaR by site-directed mutagenesis and analysis of expression on 293T cells. Replacement of these residues by other amino acid residues resulted in the loss of binding of pig STaR to STa, and as a result, STa-induced guanylyl cyclase activity was eliminated. Furthermore, mutation in a region (from Asp-347 to Val-401) which is close to the transmembrane domain caused a significant reduction in both STa-binding activity and guanylyl cyclase catalytic activity. These results suggest that the region adjacent to the transmembrane domain plays an important role in facilitating a favorable conformation of STaR for STa binding. 相似文献
96.
Keisuke Izumi Hisashi Otsuka Keizo Furuya Akiko Akagi 《Virchows Archiv : an international journal of pathology》1979,384(3):263-267
Summary The carcinogenicity of 1,2-dimethylhydrazine dihydrochloride (DMH) by oral, intragastric and subcutaneous administration was examined in 339 BALB/c mice. Subcutaneous injection of DMH induced intestinal tumors in the lower colon of all mice. After oral administration it induced a high incidence of vascular tumors in the liver and soft tissues, but colon tumors were found in only 2 mice when given at a high dosage. On intragastric administration, it induced a fairly high incidence both of colon and vascular tumors. The sites and incidences of vascular tumors and squamous cell carcinomas of the perianal glands were also described.This work was supported in part by a Grant-in Aid for Cancer Research from the Ministry of Education, Japan. 相似文献
97.
Hidekichi Takatoh Hisashi Iwamoto Mitsuru Ikezu Norio Katoh Seiki Ito Hiroshi Kaneko 《Pathology international》1987,37(5):737-746
Fourteen cases of gastrointestinal endocrine tumors were examined im-munohistochemically for peptide YY, pancreatic polypeptide, glucagon, and somatostatin. Peptide YY cells were present in seven tumors, pancreatic polypeptide cells in eight tumors, glucagon cells in six tumors, and somatostatin cells in nine tumors. All 7 rectal endocrine tumors examined were found to contain peptide YY, while in the tumors of the other sites peptide YY cells were not detected. Peptide YY cell population in the rectal tumors was small to moderate in comparison with pancreatic polypeptide and glucagon cell population. This study suggests that peptide YY cells may be a common constituent of rectal endocrine tumors together with pancreatic polypeptide and glucagon cells, and that the peptide YY spectrum of gastrointestinal endocrine tumors may be closely related to the location of the tumors. Moreover, it can also be said that peptide YY may be used as one of the markers of rectal endocrine tumors. 相似文献
98.
Hiroshi Shuto Hisashi Noguchi Hikaru Nishikata Kenji Takizawa Chizuru Shuto Makoto Nagata Yoshinori Terashi Michiya Yamaguchi Takao Takizawa Kensuke Watanabe Kaoru Tosaka Masahiko Okano Akira Koizumi 《Arerugī》2007,56(7):714-720
In general, steroid is mainly used as anti-inflammatory action in case of allergic diseases. As one of the side effects of inhalation steroid, a report is given below regarding buccal capsule/esophageal candidiasis. The patient came to the hospital with the chief complaint regarding passage dysphagia in the time of deglutition; pharyngitis and esophageal candidiasis were found by endoscopy of upper gastrointestinal tract.The interview after the endoscopy revealed that the patient, a 69-year-old female was diagnosed as chronic perennial allergic rhinitis a few years ago, and had been inhaling rhinenchysis Beclometasone dipropionate (BDP) before sleep every day for the past two years because using this collunarium seemed to mitigate the nasal obstruction and mucus during sleep. The patient did not report this fact before the endocsopy because she did not associate it with her subjective symptom. In this case, it was assumed that nebulized rhinenchysis BDP was accidentally swallowed to the pharynx and esophagus during sleep. As a treatment, rhinenchysis BDP was canceled and instead Azunol mouth washing (gargling/nasal douche) was used. No antifungal agent was used. In two weeks, the patient reported some improvement, and this was confirmed by reexamination of the upper gastrointestinal tract using endoscope in one month and a half. Pharyngitis was improved, and in the digital endoscopic assessment of esophageal candidiasis complicating inhaled steroid therapy the esophageal candidiasis became Grade I (mild grade). As for the later progress, the patient did not report any subjective symptoms such as nasal obstruction and dysphagia. In addition, the inflammation caused by candidiasis and found in the early examination was improved. The patient in this case was under treatment for thrombosis in the vein of lower extremity, but no complications such as diabetes mellitus or immune deficiency syndrome were observed. DISCUSSION: Esophageal candidiasis by chronic administration of inhalation of steroid before sleep for asthmatic patients has been reported. However, there has not been a report of esophageal candidiasis by chronic administration of rhinenchysis steroid before sleep for patients with allergic rhinitis. Similarly, in the case of the use of steroid in the form of collunarium before sleep, steroid stayed in the esophagus via the transendothelial nasal cavity, and that seemed to cause, in the long run, to develop esophageal candidiasis. CONCLUSIONS: One of the implications of the above case is that collunarium can go down, even when it is nebulized in the nasal cavity, to the esophagus via the nasal cavity to buccal capsule. This suggests the necessity for preventative measures in the case of chronic administration of steroid as follows. A. Blowing of the nose just after the use of collunarium B. Daily rinsing (gargling and nasal douche). 相似文献
99.
Inoue K Yamaguchi A Wada M Yoshimura Y Makino T Nakazaw H 《Journal of chromatography. B, Biomedical sciences and applications》2001,765(2):121-126
Due to the ubiquity of epoxy resin compounds and their potential role in increasing the risk for reproductive dysfunction and cancer, the need for an assessment of human exposure is urgent. Therefore, we developed a method for measuring bisphenol A (BPA) and bisphenol A diglycidyl ether (BADGE) metabolites in human blood samples using high-performance liquid chromatography-electrospray ionization mass spectrometry (LC-MS). Human blood samples were processed using enzymatic deconjugation of the glucuronides followed by a novel sample preparation procedure using a solid-phase-cartridge column. This selective analytical method permits rapid detection of the metabolites, free BPA and a hydrolysis product of BADGE (BADGE-40H) with detection limits in the low nanogram per milliliter range (0.1 ng ml(-1) of BPA and 0.5 ng ml(-1) of BADGE-40H). The sample extraction was achieved by Oasis HLB column on gradient elution. The recoveries of BPA and BADGE-40H added to human plasma samples were above 70.0% with a standard deviation of less than 5.0%. This selective, sensitive and accurate method will assist in elucidating potential associations between human exposure to epoxy-based compounds and adverse health effects. 相似文献
100.
Yuichi Takeoka Shao-Yuan Chen Richard L. Boyd Koichi Tsuneyama Nobuhisa Taguchi Shinji Morita Hisashi Yago Seishi Suehiro Aftab A. Ansari Leonard D. Shultz M. Eric Gershwin 《Clinical & developmental immunology》1997,5(2):79-89
It is widely accepted that the thymic microenvironment regulates normal thymopoiesis
through a highly coordinated and complex series of cellular and cytokine interactions. A direct
corollary of this is that abnormalities within the microenvironment could be of etiologic
significance in T-cell-based diseases. Our laboratory has developed a large panel of
monoclonal antibodies (mAbs) that react specifically with epithelial or nonepithelial
markers in the thymus. We have taken advantage of these reagents to characterize the
thymic microenvironment of several genetic strains of mice, including BALB/cJ,
C57BL/6J, NZB/BlnJ, SM/J, NOD/Ltz, NOD/Ltz-scid/sz, C57BL/6J-Hcph
me/Hcph me, and
ALY/NscJcl-aly/aly mice, and littermate control animals. We report herein that control
mice, including strains of several backgrounds, have a very consistent phenotypic profile
with this panel of monoclonal antibodies, including reactivity with thymic epithelial cells
in the cortex, the medulla and the corticomedullary junction, and the extracellular matrix.
In contrast, the disease-prone strains studied have unique, abnormal staining of thymic cortex
and medulla at both the structural and cellular levels. These phenotypic data suggest
that abnormalities in interactions between developing thymocytes and stromal cells characterize
disease-prone mice. 相似文献