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651.
652.
Production of the proto-oncogene BAX does not vary with changing in luteal function in women 总被引:2,自引:0,他引:2
The mechanisms of luteal maintenance and regression in women are uncertain,
but morphological and oligonucleosome studies raise the possibility that
apoptosis may be involved. BAX is a proto-oncogene of the BCL-2 family
which can induce apoptosis. The aim of this study was to determine whether
BAX is expressed in the human corpus luteum and whether the level of
expression changes relative to the stage of the luteal phase or in
simulated early pregnancy. Carefully timed samples of corpus luteum were
studied by immunostaining, sodium dodecyl sulphate-polyacrylamide gel
electrophoresis and immunoblotting. BAX protein was immunolocalized in
luteal sections from all stages including luteal rescue but BAX production
did not change during luteal maintenance or regression. Localization of BAX
to the steroid-secreting cells of the corpus luteum implies a functional
role and BAX may interact with other members of the BCL-2 family to affect
luteal function.
相似文献
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B-lymphocytic hairy cells contain no HTLV-II DNA sequences 总被引:1,自引:0,他引:1
HTLV-II has been found in some cases of the rare T-cell form of hairy- cell leukemia (HCL) and in a leukopenic chronic T-cell leukemia mimicking HCL. We asked whether the virus is implicated in the more frequent B-cell form of HCL. DNA extracted from the mononuclear cells derived from spleen (eight cases) or peripheral blood (eight cases) of 16 patients with the B-cell form of HCL was probed. No viral sequences were detected at levels of sensitivity as low as one viral genome in five cells. Therefore HTLV-II may not be involved in the B-cell form of HCL. 相似文献
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Shaker-1 is a recessive gene mutation on chromosome 7 in mice, causing both deafness and neurosensory degeneration in the inner ear. A failure of efferent innervation to the outer hair cells is being implicated in the cause of deafness (Green, 1981). To investigate the efferent innervation, we examined the cochleas of two strains of shaker-1 mutants: Sh1/Le (25 and 45 days old) and FS/Ei (28 and 68 days old), using enzymatic staining of acetylcholinesterase (AChE) for the light and electron microscopes, and also by measuring the activities of AChE and of AChE molecular forms. The enzyme levels in the SH1/Le and FS/Ei homozygotes (sh-1/sh-1) were within the range of those in SH1/Le heterozygotes (+/sh-1) and in normal mouse strains (C3H/HeJ, 129/SvJ, ICR). The picture of AChE-positive innervation in both strains differed. In the SH1/Le mutants at 25 days, the innervation appeared normal, but by 45 days it showed a marked atrophy. In the FS/Ei mutants, the degeneration was already evident by the 28th day. In the younger animals of both mutants, large differentiated vesiculated nerve endings were ultrastructurally detected in synaptic contact with outer hair cells. The preservation of AChE activity and of the expression of AChE molecular forms up to 68 days indicate that the shaker-1 cochlea may initially possess a normal input of AChE-positive efferent innervation. The late onset and the slow course of the degeneration of AChE-positive innervation seen in the SH1/Le mutants suggest that the loss of efferent endings may be, contrary to previous suggestions, the consequence rather than the cause of the shaker-1 pathology. 相似文献
660.
Mayer-Rokitansky-Kuster-Hauser syndrome: US aid to diagnosis 总被引:1,自引:0,他引:1
The Mayer-Rokitansky-Kuster-Hauser syndrome is composed of vaginal atresia with other variable Müllerian duct abnormalities such as bicornuate or septated uterus. The fallopian tubes, ovaries, and broad and round ligaments are normal. Unilateral renal and skeletal anomalies are associated in 50% and 12% of cases, respectively. Patients have a normal female karyotype and normal secondary sexual development. Previously, one had to rely on radiographic contrast studies and surgical exploration for accurate definition of the reproductive tract anatomy. The authors performed ultrasound (US) examinations on 12 patients, aged 5 days to 18 years, with the Mayer-Rokitansky syndrome. US allowed correct identification of the genitourinary anomalies found in these girls, including eight cases of unilateral renal agenesis; one absent, one rudimentary, and ten duplicated or obstructed uteri; eight duplicated or obstructed vaginas; and associated complications such as endometriosis. Eight of the patients had lower abdominal pain, often cyclical in nature. The findings demonstrate that high-resolution, real-time US in conjunction with water vaginography permits the anatomy of these complex anomalies to be defined. 相似文献