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Lack of expression of the fragile X mental retardation protein (FMRP) results in mental retardation and macroorchidism, seen as the major pathological symptoms in fragile X patients. FMRP is a cytoplasmic RNA- binding protein which cosediments with the 60S ribosomal subunit. Recently, two proteins homologous to FMRP were discovered: FXR1 and FXR2. These novel proteins interact with FMRP and with each other and they are also associated with the 60S ribosomal subunit. Here, we studied the expression pattern of the three proteins in brain and testis by immunohistochemistry. In adult brain, FMR1, FXR1 and FXR2 proteins are coexpressed in the cytoplasm of specific differentiated neurons only. However, we observed a different expression pattern in fetal brain as well as in adult and fetal testis, suggesting independent functions for the three proteins in those tissues during embryonic development and adult life.   相似文献   
3.
The entorhinal cortex (EC) plays a central role in episodic memory and is among the earliest sites of neurodegeneration and neurofibrillary tangle formation in Alzheimer’s disease. Given its importance in memory and dementia, the ability to selectively modulate gene expression or neuronal function in the EC is of widespread interest. To this end, several recent studies have taken advantage of a transgenic line in which the tetracycline transactivator (tTA) was placed under control of the neuropsin (Nop) promoter to limit transgene expression within the medial EC and pre-/parasubiculum. Although the utility of this driver is contingent on its spatial specificity, no detailed neuroanatomical analysis of its expression has yet been conducted. We therefore undertook a systematic analysis of Nop-tTA expression using a lacZ reporter and have made the complete set of histological sections available through the Rodent Brain Workbench tTA atlas, www.rbwb.org. Our findings confirm that the highest density of tTA expression is found in the EC and pre-/parasubiculum, but also reveal considerable expression in several other cortical areas. Promiscuous transgene expression may account for the appearance of pathological protein aggregates outside of the EC in mouse models of Alzheimer’s disease using this driver, as we find considerable overlap between sites of delayed amyloid deposition and regions with sparse β-galactosidase reporter labeling. While different tet-responsive lines can display individual expression characteristics, our results suggest caution when designing experiments that depend on precise localization of gene products controlled by the Nop-tTA or other spatially restrictive transgenic drivers.  相似文献   
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The efficacy of the non-steroidal anti-inflammatory analgesic, ketorolac (Toradol), was investigated in 52 day case patients undergoing removal of impacted third molar teeth under intravenous sedation and local analgesia. The study was double-blind, randomized and placebo-controlled. A single 30 mg dose of ketorolac was administered intravenously just prior to induction of sedation with midazolam. Ketorolac was well tolerated and provided good postoperative analgesia. It is suggested that ketorolac is a useful addition to the analgesic armamentarium and appropriately prescribed, provides good pain relief following day case oral surgery.  相似文献   
6.
Background Sequentially evolving intracranial bilateral haematomas, where the second haematoma develops after the surgical removal of the first one is rarely reported. Aim To report a patient who developed an epidural haematoma after evacuation of a contralateral subdural haematoma. Methods A 49-year-old male was admitted to our department after head injury. A brain computerized tomography (CT) scan revealed an acute subdural haematoma in the right temporal area which was evacuated. During his stay in the intensive care unit, he was submitted to intracranial pressure monitoring, which soon rose. Results A new CT scan showed an acute epidural haematoma in the contralateral parietal area that was also evacuated. Conclusions While rising intracranial pressure after the evacuation of a traumatic haematoma is usually attributed to brain oedema or recurrent haematoma at the craniotomy site, the development of a contralateral epidural haematoma requiring surgical treatment should not be overlooked.  相似文献   
7.
A locus for autosomal dominant anterior polar cataract on chromosome 17p   总被引:6,自引:3,他引:6  
Inherited cataract is a clinically and genetically heterogeneous disease. Here we report the identification of a new locus for an autosomal dominant anterior polar cataract on the short arm of chromosome 17. To map this new locus we performed genetic linkage analysis with microsatellite markers in a four-generation pedigree. After exclusion of seven candidate loci for cataract, we obtained significant positive LOD scores for markers D17S849 (Z = 4.01 / theta = 0.05) and D17S796 (Z = 4.17 / theta = 0.05). Multipoint analysis gave a maximum LOD score of 5.2 (theta max = 0.06) between these two markers. From haplotype analysis, the cataract locus lies in the 13 cM interval between markers D17S849 and D17S796. This study provides the first genetic mapping of an autosomal dominant anterior polar cataract.   相似文献   
8.
Administration of supraphysiological doses of testosterone to normal men causes inhibition of spermatogenesis, but while most become azoospermic, 30-55% maintain a low rate of spermatogenesis. We have investigated whether there are differences in endogenous androgen production, of testicular and adrenal origin, which may be related to the degree of suppression of spermatogenesis. Thirty-three healthy Caucasian men were given weekly i.m. injections of 200 mg testosterone oenanthate (TE), 18 became azoospermic, while 15 remained oligozoospermic. Urinary excretion of epitestosterone, a specific testicular product, was reduced to <10% of pretreatment values, with no differences between the groups. Similar results were obtained for other markers of testicular steroidogenesis. Urinary and plasma adrenal androgens were also reduced during TE treatment: a statistically significant decrease in both (P < 0.001 and P < 0.05 respectively) was seen in the azoospermic but not oligozoospermic responders. These results suggest that testicular steroidogenesis is decreased to <10% by the administration of supraphysiological doses of exogenous testosterone. Differences in the degree of ongoing steroidogenesis in the testis do not appear to account for incomplete suppression of spermatogenesis, thus differences in androgen metabolism may underlie this heterogeneous response. A small but significant reduction in secretion of adrenal androgens was also detectable, the relevance of which is unclear.   相似文献   
9.
OBJECTIVES: Oral hairy leukoplakia (HL) is an acan-thotic, hyperparakeratotic lesion characterised by the presence of a replicative Epstein-Barr virus (EBV) infection in the superficial and adjoining layers of the epithelium. EBV or its gene products are capable of modifying epithelial differentiation. The aim of this study was to establish whether the presence of EBV was associated with an alteration in cell turnover by assessing bromodeoxyuridine (BrdU) incorporation and Ki 67 expression in lesional tissue and control mucosa.
METHODS: Biopsies of HL together with age, site and sex matched controls ( n = 7 and 8 respectively) were incubated in 200 μM BrdU in vitro , fixed in methacarn and processed to paraffin wax. Following acid hydrolysis, incorporated BrdU and Ki 67 were identified in serial 5 fim sections using a three-stage immunoperoxidase technique and cell density expressed as the number of positive cells per mm basement membrane length.
RESULTS: Overall, there was no difference in the number of BrdU positive cells per mm basement membrane length between control and HL tissue. However, within HL alone, the presence'of focal EBV replication was associated with a significant reduction in the number of basal cells incorporating BrdU compared to adjacent EBV free areas (P < 0.05). There was no significant difference between Ki 67 positive cells in control and HL tissue and no evidence of a reduction of Ki 67 positive cells in areas associated with EBV replication.
CONCLUSIONS: These results suggest that there is no evidence of a generalised alteration of the proliferative capacity of basal cells in HL, although the focal reduction in BrdU incorporation may reflect subtle changes on cell turnover by EBV infection.  相似文献   
10.
Kunicki  TJ; Pidard  D; Rosa  JP; Nurden  AT 《Blood》1981,58(2):268-278
Triton X-100 soluble proteins from 125I-labeled human platelets were studied by crossed immunoelectrophoresis employing a multispecific rabbit antibody raised against whole normal platelets. Emphasis was placed upon an analysis of immunoprecipitates containing 125I-labeled major membrane glycoproteins, and in particular, a prominent immunoprecipitate containing a glycoprotein antigen (s) previously designated as protein 16. SDS-polyacrylamide gel electrophoresis of protein 16 precipitated by a monospecific alloantibody. IgG L . . . , confirmed the presence of both glycoproteins IIb and IIIa. 125I-IgG L . . . , at concentration below that capable of precipitating protein 16 by itself, bound specifically to the precipitate containing protein 16 produced by the multispecific rabbit antibody. No other precipitates formed by the rabbit antibody contained either glycoprotein IIb or IIIa. When platelet proteins, incubated with optimum concentrations of ethylenediamine tetraacetic acid (EDTA) or ethyleneglycol bis (B- aminoethylether) NN1-tetraacetic acid (EGTA), were electrophoresed against the rabbit antibody, previously unobserved immunoprecipitates that contained either free glycoprotein IIb or free glycoprotein IIIa were detected. Upon readdition of excess Ca++, but not Mg++, to the same protein samples, a single immunoprecipitate containing both glycoproteins was once again observed. It is thus demonstrated that glycoproteins IIb and IIIa can form Ca++-dependent complexes (protein 16) in Triton X-100 extracts of normal platelets. The potential significance of the reversible association of these glycoproteins to normal platelet function is discussed.  相似文献   
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