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41.
42.
Y chromosome microdeletions, in azoospermic or near-azoospermic subjects, are located in the AZFc (DAZ) subregion 总被引:9,自引:2,他引:9
Submicroscopic deletions of the Y chromosome and polymorphisms of the
androgen receptor (AR) gene in the X chromosome have been observed in men
with defective spermatogenesis. To further define the subregions/genes in
the Y chromosome causing male infertility and its relationship to
polymorphisms of the AR polyglutamine tract, we screened the genomic DNA of
202 subfertile males and 101 healthy fertile controls of predominantly
Chinese ethnic origin. Y microdeletions were examined with 16
sequence-tagged site (STS) probes, including the RBM and DAZ genes,
spanning the AZFb and AZFc subregions of Yq11, and related to the size of
trinucleotide repeat encoding the AR polyglutamine tract. Y microdeletions
were detected and confirmed in three out of 44 (6.8%) of azoospermic and
three out of 86 (3.5%) severely oligozoospermic patients. No deletions were
detected in any of the patients with sperm counts of >0.5 x 10(6)/ml,
nor in any of the 101 fertile controls. All six affected patients had
almost contiguous Y microdeletions spanning the entire AZFc region
including the DAZ gene. The AZFb region, containing the RBM1 gene, was
intact in five of the six subjects. Y deletions were not found in those
with long AR polyglutamine tracts. Our study, the first in a Chinese
population, suggest a cause and effect relationship between Y
microdeletions in the AZFc region (possibly DAZ), and azoospermia or
near-azoospermia. Y microdeletions and long AR polyglutamine tracts appear
to be independent contributors to male infertility.
相似文献
43.
44.
CD39 activity correlates with stage and inhibits platelet reactivity in chronic lymphocytic leukemia
Dianne Pulte Kim E Olson M Johan Broekman Naziba Islam Harold S Ballard Richard R Furman Ashley E Olson Aaron J Marcus 《Journal of translational medicine》2007,5(1):23
Background
Chronic lymphocytic leukemia (CLL) is characterized by accumulation of mature appearing lymphocytes and is rarely complicated by thrombosis. One possible explanation for the paucity of thrombotic events in these patients may be the presence of the ecto-nucleotidase CD39/NTDPase-1 on the surface of the malignant cells in CLL. CD39 is the major promoter of platelet inhibition in vivo via its metabolism of ADP to AMP. We hypothesize that if CD39 is observed on CLL cells, then patients with CLL may be relatively protected against platelet aggregation and recruitment and that CD39 may have other effects on CLL, including modulation of the disease, via its metabolism of ATP. 相似文献45.
Cellular and developmental patterns of expression of Ret and glial cell line-derived neurotrophic factor receptor alpha mRNAs 总被引:6,自引:0,他引:6
C. A. Nosrat Andreas Tomac Barry J. Hoffer Lars Olson 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1997,115(3):410-422
Glial cell line-derived neurotrophic factor (GDNF) has recently been shown to signal by binding to GDNF receptor-alpha (GDNFR-α),
after which the GDNF-GDNFR-α associates with and activates the tyrosine kinase receptor Ret. We have localized Ret messenger
RNA (mRNA) in the developing and adult rodent and compared with to the expression of GDNF and GDNFR-α mRNA. Ret mRNA is strongly
expressed in dopamine neurons and α-motorneurons as well as in thalamus, ruber and occlumotor nuclei, the habenular complex,
septum, cerebellum, and brain stem nuclei. Ret mRNA was also found in several sensory systems, in ganglia, and in nonneuronal
tissues such as teeth and vibrissae. Very strong Ret mRNA signals are present in kidney and the gastrointestinal tract, where
Ret and GDNF mRNA expression patterns are precisely complementary. The presence of Ret protein was confirmed in adult dopamine
neurons using immunohistochemistry. GDNFR-α mRNA was strongly expressed in the developing and adult dopamine neurons. It was
also found in neurons in deep layers of cortex cerebri, in hippocampus, septum, the dentate gyrus, tectum, and the developing
spinal cord. In the kidney and the gastrointestinal tract, GDNFR-α mRNA and Ret mRNA distribution overlapped. Dorsal root
ganglia, cranial ganglia, and developing peripheral nerves were also positive. GDNFR-α was additionally found in sensory areas
and in developing teeth. Sensory areas included inner ear, eye, olfactory epithelium, and the vomeronasal organ, as well as
developing tongue papillae. The temporospatial pattern of expression of GDNFR-α mRNA did not always match that of Ret mRNA.
For instance, GDNFR-α mRNA was also found in the developing ventral striatum, including the olfactory tubercle, and in hippocampus.
These areas seemed devoid of Ret mRNA, suggesting that GDNFR-α might also have functions unrelated to Ret.
Received: 2 January 1997 / Accepted: 26 February 1997 相似文献
46.
The distribution of monomeric and polymeric actin in spermatozoa from the bull, boar, rabbit, human, rat, mouse, golden hamster, and guinea pig has been examined by using a monoclonal antiactin antibody and NBD-phallacidin. Actin was present in sperm from each species. When the monoclonal antibody was used, there was a species-specific distribution and intensity of fluorescence, but no generalized pattern. Specific fluorescence was noted in the neck and principal piece of human sperm; in the postacrosomal region, neck, and midpiece of bull and boar sperm; in the postacrosomal region, neck, and principal/equatorial segment border of rabbit sperm; in the neck region of hamster sperm; and in the neck, midpiece, and principal piece of rat, mouse, and guinea pig sperm. Sperm from all eight species displayed no specific fluorescence with NBD-phallacidin, indicating that actin was present in a nonfilamentous form. SDS extracts of sperm were analyzed by SDS-PAGE and Western blotting; in sperm from each species, a 42-kD protein with specific affinity for the monoclonal antibody was present. 相似文献
47.
M L Olson C J Shanholtzer K E Willard L R Peterson 《American journal of clinical pathology》1991,96(4):454-458
A slide centrifuge Gram stain procedure was performed to screen for bacteriuria 4161 urine specimens submitted in urine preservative tubes for routine culture. For slide centrifuge Gram staining, each urine sample was mixed well. Thereafter, 0.2 mL of each sample was placed, using a pipette, into a slide centrifuge chamber and centrifuged at 2,000 rpm for 5 minutes. The slides were heat fixed, Gram stained, and read by laboratory personnel who scanned 12 consecutive oil-immersion fields using a set pattern. The presence of the same organism in six or more fields was defined as a positive urine screen. Urine samples were cultured using a 0.001-mL loop and a comparison of culture growth with slide centrifuge screening was made. When growth of 100,000 or more colony-forming units per milliliter (CFU/mL) was the reference for comparison, the screen had a sensitivity rate of 98%, a specificity rate of 90%, a negative predictive value of 99%, and a positive predictive value of 65%. When a lower colony count of 10,000 or more CFU/mL was the reference for comparison, the screen had a sensitivity rate of 88%, a specificity rate of 95%, a negative predictive value of 96%, and a positive predictive value of 84%. The slide centrifuge Gram stain is a very sensitive screening method to detect bacteriuria in an adult male population. 相似文献
48.
Evidence for platelet-activating factor as a late-phase mediator of chronic pancreatitis in the rat. 总被引:3,自引:0,他引:3 下载免费PDF全文
W. G. Zhou W. Chao B. A. Levine M. S. Olson 《The American journal of pathology》1990,137(6):1501-1508
The role of platelet-activating factor (PAF) as a mediator of pancreatic inflammation was examined in the rat pancreatic duct ligation model of obstructive pancreatitis. Pancreatic generation of PAF, as measured by bioassay (ie, platelet [3H]serotonin secretion), was determined at various times after induction of inflammation. Tissue levels of PAF in the normal pancreas averaged 600 +/- 49 pg/g, but PAF was not detectable during the initial 24 hours of pancreatitis, a time when the inflammatory reaction would be considered acute, that is, during the period of maximal serum amylase release and the development of interstitial edema. However a substantial increase in pancreatic PAF levels (12 times control levels) was observed 7 to 14 days after duct ligation during the late-phase response interval similar to the situation characteristic of chronic pancreatitis in which parenchymal atrophy, fibrosis, and pancreatic insufficiency evolve. One week after duct ligation when PAF levels peaked, an evaluation was made of the effects of PAF antagonists (BN52021 and WEB2170) on pancreatic lesions using Evan's blue extravasation, pancreatic myeloperoxidase (MPO) activity, and acid phosphatase activity in peritoneal lavage fluid. BN52021 or WEB2170 treatment was shown to reduce pancreatic damage and inflammation significantly. Long-term in vivo administration of exogenous PAF (20 micrograms/kg/hr for 7 days) exhibited a reduction of [3H]thymidine uptake into and amylase release from pancreatic acini in vitro. Our observations 1) that pancreatic PAF levels increased significantly during the chronic phase of obstructive pancreatitis induced by duct ligation; 2) that inhibition of the action of PAF, through specific receptor antagonism, caused an attenuation of pancreatic lesions; and 3) that chronic administration of PAF resulted in decreased pancreatic regeneration and exocrine function are consistent with a pivotal role for PAF as a late-phase inflammatory mediator in chronic pancreatitis in rats. 相似文献
49.
Locus coeruleus and cortex cerebri from embryonic (ED 17) and newborn rats were kept 4 days in tissue culture under conditions maintaining organotypic features and then transplanted to the anterior chamber of the eye of adult rats. Vascularization from the host iris was delayed in pre-cultured grafts as compared to directly grafted material. In spite of this, several morphological parameters developed normally. Thus, pre-cultured grafts grew considerably in oculo. Falck-Hillarp histochemistry showed that grafts of cortex cerebri received an adrenergic innervation from the host iris and that locus coeruleus grafts contained central adrenergic neurons capable of innervating a sympathetically denervated host iris. The successful combination of tissue culture and intraocular transplantation should permit the selective advantages of both techniques to be applied to the same tissue pieces, generating new information unobtainable by either method alone. 相似文献
50.
Intraocular grafts of embryonic rat septum and co-grafts of septum plus hippocampus were studied with immunohistochemical markers after one and six months (short term) and 12 months (long term) of survival. Neurons in all the septal tissues expressed the epitope for the rat beta-nerve growth factor receptor in sections reacted with the monoclonal antibody 192-IgG. Stained fibers traversed the interface of the short and long term co-grafts and 192-IgG-positive processes were most prominent in the septum when combined with the hippocampal formation. In contrast, labeled processes were sparse and the perikarya of positive neurons appeared shrunken in the long term single septal transplants. Axon and dendrite profiles in the grafts were examined with antibodies that recognize the phosphorylated heavy neurofilament unit (RT97) and the high molecular weight microtubule-associated protein termed MAP 2, respectively. In the short term single and double grafts, characteristic arrays of RT97-positive processes defined the tissues and axonal tracts connecting the septum with the hippocampus. Typical immunostaining of the neuronal somas and the dendrite arbors were were outlined with the MAP 2 antibody. After one year in oculo, extensive changes in the patterns of axonal and dendritic immunoreactivity were noted in the isolated septal grafts. Abnormalities identified with the RT97 antibody included hypertrophied axons, short fragments of kinked axons and neurofilaments in the neuronal perikarya. The formation of circular "abnormal fiber aggregates" composed of densely packed abnormal and normal axonal processes were also distinctive in only the long term single septal transplants. In addition, a reduction in the density of dendrites and the presence of truncated arbors stained with the MAP 2 antibody suggested that regression of the dendrites had occurred. These spatial modifications in axonal and dendritic staining were not present in the septal portion of the combined preparations. In astrocytes, an increase in the antigenicity to glial fibrillary acidic protein paralleled the age of the transplant and was most extensive in the septal grafts. The results illustrate that intraocular co-grafts of hippocampus protect septal neurons and glial cells from abnormal changes in immunoreactivity to antibodies directed against cytoskeletal proteins and exemplify the long term supportive effects of the hippocampus on the morphology of septal neurons, including neurons that express the receptor for nerve growth factor. 相似文献