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81.
Toshiie Sakata Masataka Fukushima Koichiro Tsutsui Koichi Arase Kazuma Fujimoto 《Physiology & behavior》1982,28(4):641-647
To test the possibility that theophylline induced circadian disappearance of food intake might depend upon rhythmic disruption of blood glucose, insulin and free fatty acids (FFA), theophylline was administered chronically. This markedly lengthened postprandial intermeal intervals during the dark, and induced approximately identical intermeal intervals and identical meal sizes in the light and dark periods. In contrast to the clear light-dark dependent oscillations of serum glucose, insulin and FFA in the controls, the theophyllinized rats lost circadian fluctuation of each of these three chemical substances. Further, theophyllinized rats, unlike controls, had no time-dependent fluctuation in the levels of these substances at ? 120, ?60 or ?15 min preceding the onset of the first meal before the dark. These findings, together with previous reports, explain the disappearance of nocturnal feeding rhythm in theophyllinized rats in terms of functional destruction of circadian regulation in the hypothalamus which modulate the production of chemical determinants of food intake. 相似文献
82.
83.
A case with tumorous deformity of the posterior mitral valve leaflet after spontaneous chordal rupture in a child is described. A partial rupture in the chordae tendineae of the posterior mitral leaflet was found by echocardiography in a 9-year-old Japanese boy. Tumorous bulging was gradually developed in the leaflet and was surgically excised 5 years later. Multiple nodular tumors were found on the atrial surface of the posterior mitral leaflet. Histological examination revealed that the tumorous bulging consisted of myxomatous materials in which collagen fibrils and very fine elastic fibers were distributed loosely and irregularly. Normal-looking endothelial cells covered the luminal surface of the bulging lesion. Vimentin-positive spindle-shaped mesenchymal cells were scattered in the bulge area. The labeling index of proliferating cell nuclear antigen (PCNA) in these cells was 29.3%. These spindle cells were positive for matrix metalloproteinase (MMP)-1 in the entire bulge area. The cells and matrix were positive for MMP-2 and tissue inhibitor of MMP (TIMP)-1 in the basal area of bulging, but were weakly positive or negative at the surface area. Reactivity for TIMP-2 in the cells in the bulge area was obviously weaker than that in the cells at the spongiosa of the anterior mitral leaflet, which was obtained from the patient at the valve replacement operation 9 months after the initial operation. These findings indicated that the tumorous deformity of the mitral valve was formed by the overgrowth of valve tissue under the stimulation of mitral regurgitation in this child, and the imbalance of MMP and TIMP might play an important role in the bulge formation. 相似文献
84.
Ikegaya H Iwase H Zheng HY Nakajima M Sakurada K Takatori T Fukayama M Kitamura T Yogo Y 《Journal of virological methods》2005,126(1-2):37-43
Recently genotyping of JC virus (JCV) DNA in renal tissue was reported to be useful to identify the geographic origin of unidentified cadavers. In the above study, autopsied tissue samples without storage or stored in a frozen state were used. This study examined JCV DNA sequence modifications caused by formalin-fixation, in an attempt to elucidate whether formalin-fixed, paraffin-embedded tissue samples can also be used to determine the genotypes of JCV DNA in the kidney. In four cases, a 610 bp typing region of the JCV genome was PCR-amplified from renal tissues stored for 1 year in three different states: frozen at -80 degrees C [Amaker, B.H., Chandler, F.W., Huey, L.O., Colwell, R.M., 1997. Molecular detection of JC virus in embalmed, formalin-fixed, paraffin-embedded brain tissue. J. Forensic Sci., 1157-1159], formalin-fixed, paraffin-embedded [Ault, G.S., Stoner, G.L., 1992. Two major types of JC virus defined in progressive multifocal leukoencephalopathy brain by early and late coding region DNA sequences. J. Gen. Virol. 73, 2669-2678], and soaked in 5% formalin [Baksh, F.K., Finkelstein, S.D., Swalskey, P.A., Stoner, G.L., Ryschkewitsch, C.F., Randhawa, P.R., 2001. Molecular genotyping of BK and JC virus in human polyomavirus-associated interstitial nephritis after renal transplantation. Am. J. Kidney Dis. 38 (2), 354-365]. The amplified fragments were cloned, and the resultant clones were sequenced. In frozen samples, single sequences ('original' sequences) were detected in all cases. In formalin-fixed, paraffin-embedded samples, not only the original sequences but also those with 1-6 base substitutions were detected. From formalin-soaked samples, the original sequences and those with 1-5 and 10-13 substitutions were detected. The genotyping of JCV DNA was not hampered by the presence of 1-6 substitutions, but a shift in JCV genotypes was observed in sequences with 10-13 substitutions. Thus, it was concluded that the genotypes of JCV DNA in the kidney can be determined only with specimens stored in a frozen state or formalin-fixed for a short time. 相似文献
85.
86.
PURPOSE: There have been few reports on correlations between resection volume of benign prostatic hyperplasia, body mass index (BMI) and estrogen. This study was undertaken to evaluate the correlations. METHOD: In this study, we considered 50 patients who had benign prostatic hyperplasia (BPH) and underwent suprapubic prostatectomy (SPP). Men with prostate cancer or prior prostate surgery were excluded. The relationship between prostate resection volume and BMI was examined. Additionally, patients were divided into two groups according to BMI: less than 25, and more than 25. The two groups were evaluated according to stained estrogen receptors. RESULTS: BMI was correlated positively with prostate volume (p < 0.01). However, positive rates of estrogen receptors showed no significant difference between the two groups. CONCLUSIONS: This was a study describing the relationship between BMI and prostate volume. Obesity has been hypothesized to be associated with BPH because of the endocrine changes in men that occur with age, including increased estrogen and decreased testosterone. Our findings suggest that estrogen may play a pathophysiologic role in benign prostatic hyperplasia. Further studies of large populations are needed to validate this assumption. 相似文献
87.
Tolerance to self gangliosides is the major factor restricting the antibody response to lipopolysaccharide core oligosaccharides in Campylobacter jejuni strains associated with Guillain-Barré syndrome
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Bowes T Wagner ER Boffey J Nicholl D Cochrane L Benboubetra M Conner J Furukawa K Furukawa K Willison HJ 《Infection and immunity》2002,70(9):5008-5018
Guillain-Barré syndrome following Campylobacter jejuni infection is frequently associated with anti-ganglioside autoantibodies mediated by molecular mimicry with ganglioside-like oligosaccharides on bacterial lipopolysaccharide (LPS). The regulation of antibody responses to these T-cell-independent antigens is poorly understood, and only a minority of Campylobacter-infected individuals develop anti-ganglioside antibodies. This study investigates the response to gangliosides and LPS in strains of mice by using a range of immunization strategies. In normal mice following intraperitoneal immunization, antibody responses to gangliosides and LPS are low level but can be enhanced by the antigen format or coadministration of protein to recruit T-cell help. Class switching from the predominant immunoglobulin M (IgM) response to IgG3 occurs at low levels, suggesting B1-cell involvement. Systemic immunization results in poor responses. In GalNAc transferase knockout mice that lack all complex gangliosides and instead express high levels of GM3 and GD3, generation of anti-ganglioside antibodies upon immunization with either complex gangliosides or ganglioside-mimicking LPS is greatly enhanced and exhibits class switching to T-cell-dependent IgG isotypes and immunological memory, indicating that tolerance to self gangliosides is a major regulatory factor. Responses to GD3 are suppressed in knockout mice compared with wild-type mice, in which responses to GD3 are induced specifically by GD3 and as a result of polyclonal B-cell activation by LPS. The anti-ganglioside response generated in response to LPS is also dependent on the epitope density of the ganglioside mimicked and can be further manipulated by providing secondary signals via lipid A and CD40 ligation. 相似文献
88.
Jun Nakura Lin Ye Koichi Kihara Hidehisa Yamagata Kouzin Kamino Yusuke Nakamura Tetsuro Miki Toshio Ogihara 《Journal of human genetics》1995,40(3):281-282
Two polymorphic dinucleotide (CA) repeat clones were isolated from cosmids, cCI8-1121 and cCI8-1199, mapped to chromosome 8p11.2-p12. 相似文献
89.
D2-40 antibody immunoreactivity in developing human brain, brain tumors and cultured neural cells. 总被引:1,自引:0,他引:1
Yasuhiro Nakamura Yonehiro Kanemura Tomiko Yamada Yasuo Sugita Koichi Higaki Munehiko Yamamoto Mitsuhiko Takahashi Mami Yamasaki 《Modern pathology》2006,19(7):974-985
D2-40 antibody is raised against an oncofetal antigen, the M2A antigen. It has been used as a marker for lymphatic endothelium as well as mesothelioma and cerebellar hemangioblastoma. We demonstrate here that positive D2-40 immunoreactivity was found in the developing cerebrum, particularly in the germinal matrix layer, immature ependyma, choroid plexus and meninges. In the developing cerebellum, positive D2-40 immunoreactivity was found in the external granular layer particularly of the outer portion and the Purkinje cell layer as well as meninges. Some brain tumors such as anaplastic ependymoma, some medulloblastomas, glioblastoma, pineal germinoma, craniopharyngioma, choroid plexus papilloma, choroid plexus carcinoma, and meningioma showed positive immunoreactivity with D2-40. Therefore, D2-40 antibody is considered a useful marker for research on developing brain and diagnosis of brain tumors, differentiation between choroid plexus carcinoma and metastatic carcinoma. In addition, on cultured human neural cells, D2-40 immunoreactivity was found in nestin-positive neural stem/progenitor cells and neuronal lineage cells. As D2-40 antibody recognizes cell surface antigen M2A, it might be a candidate cell surface marker for isolation of human neural stem cells/neuronal lineage cells in the fluorescence-activated cell sorting technique. 相似文献
90.
Naoya Nakamura Naoyoshi Mori Koichi Ohshima Tetsuo Kuze Yuko Hashimoto Yoshikazu Sasaki Asumi Shirakawa Michiko Sato Masafumi Abe 《Diagnostic molecular pathology》2002,11(2):83-89
We examined nucleotide sequences of Epstein-Barr virus (EBV)-positive Hodgkin/Reed-Sternberg (HRS)-like B cells in a case of diffuse large B-cell lymphoma (DLBCL) and a case of adult T-cell lymphoma (ATL) for single-cell polymerase chain reaction of the immunoglobulin heavy-chain gene variable region (VH gene). HRS-like B cells were scattered in the area irrelevant to the lymphoma infiltrates of DLBCL and in the lymphoma area of ATL. HRS-like B cells were positive for CD20 and CD30 but negative for CD15. EBV presented in HRS-like B cells in both cases but not in any lymphoma cells. VH genes of five HRS-like B cells analyzed in DLBCL were polyclonal and showed in-frame sequences with 0% to 2.8% somatic mutation frequency. In an ATL, VH genes of five HRS-like B cells analyzed were polyclonal and somatically mutated. Four cells carried in-frame rearrangements with 3.5% to 17.7% mutation frequency. One of the VH genes has a one-codon deletion. From the fifth cell, an out-of-frame rearrangement with an insertion and a deletion was obtained. Thus, we showed polyclonal EBV-positive HRS-like B cells in both DLBCL and ATL and that whereas EBV-positive, HRS-like B cells in DLBCL exhibited unmutated and mutated VH gene, those in ATL were found to have a somatically mutated VH gene with/without deletions and/or insertions. The HRS-like B cells may appear because of active EBV infection in a patient who is immunosuppressed from the primary lymphoma. 相似文献