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41.
We previously reported that ammonia induced apoptosis in cultured rat hippocampal neurons with moderate increases in the intracellular calcium concentration and decreases in phospho-BAD levels. Since this suggested the involvement of calcineurin in the apoptosis, the effects of calcineurin inhibitors, 1 microM cyclosporin A and 1 microM FK506, on the ammonia-induced neuronal apoptosis were tested. Both of the inhibitors abolished the neuronal apoptosis assessed by double staining with Hoechst 33258 and anti-neurofilament antibody, and the ammonia-induced decrease in phospho-BAD Ser(155) level. Thus, calcineurin appeared to be involved in the dephosphorylation of BAD at the sites including Ser(155) in ammonia-induced apoptosis. 相似文献
42.
Immunohistochemical localization of 3β-hydroxysteroid dehydrogenase/Δ5→4-isomerase (3β-HSD), which converts Δ5-3β-hydroxysteroids to Δ4-3-ketosteroids, was performed in the human adrenal gland and in its disorders by employing a specific antibody raised against
the enzyme purified from human placenta. Immunoreactivity of 3β-HSD was present in all three cortical zones of the adrenal
glands obtained at autopsy, while in surgically removed adrenal glands, immunoreactivity was dominant in the zona fasciculata
(ZF), with faint immunoreactivity in the zona glomerulosa (ZG) and the zona reticularis (ZR). Intracortical localization of
3β-HSD in the adrenal glands obtained at autopsy may represent an adrenal adaptation to antemortem stress, with shifting of
adrenal pregnenolone- a substrate of 3β-HSD - as well as steroid 17α-hydroxylase from adrenal androgen synthesis to glucocorticoid
synthesis. In adrenocortical hyperplasia, marked immunoreactivity was observed in the ZG and outer ZF in adrenal glands with
idiopathic hyperaldosteronism and in the ZF and ZR, especially in cortical micronodules, in the adrenal glands associated
with Cushing’s disease. In aldosteronoma and Cushing’s adenoma, immunoreactivity of the enzyme was much more intense in large
clear tumor cells than in small compact tumor cells. Immunolocalization of 3β-HSD can yield important information toward an
understanding of adrenal steroid metabolism in both physiological and pathological processes. 相似文献
43.
Hlronobu Sasano Fumiko Date Hironao Yamamoto Hiroshi Nagura 《Pathology international》1997,47(9):647-650
A case of anglomyofibroblastoma of the vulva in a 49-year-old woman was examined. The tumor measured 3×2.5×2 cm and appeared light gray to tan In color on the cut surface. Light microscopic examinations revealed that spindle or oval shaped tumor cells were arranged in loose edematous stroma with numerous thin-walled vessels. Ultrastructurally, cell organellae were not well developed but intracytoplasmic filaments of intermediate size were abundant in the tumor cells. Desmin, CD34 and vimentin immunoreactivity were detected in almost all of the tumor cells. Both estrogen and progesterone receptors were diffusely expressed In the tumor, suggestive of the sex sterold-dependency of this tumor. The Ki-67 labeling index was less than 1% and the DNA content of the tumor cells, which was examined by image cytometry, demonstrated diploidy (DNA index=0.97). These findings may reflect the quiescent or slow growing features of angiomyofibroblastoma. 相似文献
44.
Multipotent, self-renewing stem and progenitor cells isolated from the mammalian central nervous system (CNS) have been shown to survive as allografts following transplantation to sites throughout the neuraxis. However, studies of this type shed little light upon the immunologic properties of the cells themselves, primarily because little is learned about the intrinsic immunogenic properties of a cell when it is grafted into an immune-privileged site. We have therefore investigated the immunogenic and antigenic properties of CNS progenitor cells by grafting them into a conventional (i.e., non-immune-privileged) site, namely, beneath the kidney capsule. Our results indicate that allogeneic CNS progenitor cells survive at least 4 weeks in a conventional site, during which time they neither sensitize their hosts nor express detectable levels of major histocompatibility complex (MHC) class I or II. These in vivo data are in accord with flow cytometric results showing that CNS progenitor cells do not express MHC class I or class II, either at baseline or upon differentiation in 10% serum. Exposure to interferon gamma, however, reversibly upregulates expression of these key transplantation antigens. Together, these results reveal CNS progenitor cells to possess inherent immune privilege. Since CNS progenitor cell allografts were rejected beneath the kidney capsule following specific sensitization of the host, CNS progenitor cells were able to display alloantigens, albeit not in an immunogenic form. 相似文献
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48.
Kiyoshi Imaizumi Junko Kimura Mari Matsuo Kenji Kurosawa Mitsuo Masuno Norio Niikawa Yoshikazu Kuroki 《American journal of medical genetics》2002,107(1):58-60
We describe a de novo balanced reciprocal translocation between the long arms of chromosomes 5 and 8 [46,XX,t(5;8)(q35;q24.1)] in a 15-month-old girl with a typical Sotos syndrome phenotype. Involvement of the 5q35 region was previously reported (Maroun et al. [1994: Am J Med Genet 50:291-293]) as one of translocation breakpoints in the present patient. We suggest that the gene responsible for Sotos syndrome is located to a distal long-arm region of chromosome 5. 相似文献
49.
Expression of stanniocalcin in zona glomerulosa and medulla of normal human adrenal glands, and some adrenal tumors and cell lines 总被引:2,自引:0,他引:2
50.
Shimada M Hino F Yamamoto J Mukai H Hosobe T Onodera S Hoshina S Machida K 《Rinsho byori. The Japanese journal of clinical pathology》2003,51(11):1061-1067
The isothermal and chimeric primer-initiated amplification of nucleic acids (ICAN) is a new isothermal DNA amplification method composed of exo Bca DNA polymerase, RNaseH and DNA-RNA chimeric primers. We developed the simultaneous detection system for Chlamydia trachomatis/Neisseria gonorrhoeae DNA, combined with luminescence detection by a probe hybridization. In the performance tests, this system was able to detect 10 to 100 copies of C. trachomatis/N. gonorrhoeae DNA for only 3.5 hours, and was highly specific to C. trachomatis/N. gonorrhoeae without any cross-reaction to C. pneumoniae, N. lactamica, N. sicca or N. meningitidis. When we tested 60 clinical samples of urine and cervical swabs, the interpretive results were completely consistent with those obtained by Roche PCR system. Of 13 positive samples by the ICAN and PCR systems for C. trachomatis, four were negative by EIA method(IDEIA Chlamydia). These results indicate that the ICAN system is an efficient and sensitive system to simultaneously detect C. trachomatis/N. gonorrhoeae DNA. 相似文献