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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.
Cortical motor and somatosensory representation: effect of cerebral lesions   总被引:12,自引:0,他引:12  
OBJECT: Changes in cortical representation in patients with cerebral lesions may alter the correlation between cortical anatomy and function. This is of potential clinical significance when the extent of cortical resection is based on surface anatomical landmarks. METHODS: Fifty-one patients with supratentorial lesions were studied. Nineteen harbored noncentral lesions (no involvement of pre- or postcentral gyrus), whereas 32 had central lesions. Control studies consisted of stimulation of the hand contralateral to the unaffected hemisphere. Positron emission tomography activation studies were performed using the [15O]H2O tracer. Somatosensory stimulation of the hand or foot was performed using a mechanical vibrator. Motor activation consisted of hand clenching or foot tapping. The t-statistic volumes were generated from images showing the mean change in regional cerebral blood flow, and coregistered with a T1-weighted magnetic resonance image. At the threshold selected, exclusive contralateral primary sensorimotor cortex activation was elicited in 100% of the control studies. A different pattern of cortical activation was associated with central lesions in 35 (78%) of 45 patients, which occurred significantly more often than with noncentral lesions (eight [31%] of 26 patients). The most common difference in the pattern of activation with central lesions was activation of cortical regions outside the central area (including the supplementary sensorimotor area and the secondary somatosensory cortex). No sensorimotor activation was observed in gyri adjacent to the pre- or postcentral gyrus. CONCLUSIONS: Central lesions are more frequently associated with altered patterns in activation than lesions in noncentral locations. Characteristic patterns include activation of secondary sensorimotor areas. The absence of activation in gyri adjacent to the sensorimotor strip has clinical significance for the planning of resections in the central area.  相似文献   
4.
BACKGROUND: Patients with Type 2 diabetes and albuminuria are at high risk to progress to end-stage renal disease (ESRD). Although angiotensin receptor blockers confer renoprotection, many diabetic patients still develop overt nephropathy and reach ESRD. Glycosaminoglycans belong to the same family as heparin and heparinoids. Pilot studies with sulodexide, a glycosaminoglycan, have shown that sulodexide can reduce urinary albumin excretion rates in diabetic patients. No hard renal end-point data are available. METHODS: Two multicentre, double-masked, randomized placebo controlled trials were designed to study the renoprotective potential of sulodexide. The Sulodexide Microalbuminuria Trial examined the efficacy of sulodexide given over 26 weeks in 1000 patients with Type 2 diabetes, hypertension and microalbuminuria. The Sulodexide Overt Nephropathy Trial examined the efficacy of sulodexide in 2240 patients with Type 2 diabetes, hypertension and proteinuria > or = 900 mg/24 h. RESULTS: The primary outcome of The Sulodexide Microalbuminuria Trial was (i) conversion to normoalbuminuria and at least a 25% decrease in the urinary albumin creatinine ratio (UACR), or (ii) at least a 50% reduction in UACR. The primary outcome of The Sulodexide Overt Nephropathy Trial was time to a composite end point of doubling of serum creatinine or ESRD. CONCLUSIONS: The sulodexide nephropathy programme will document whether therapy with sulodexide confers renal protection in Type 2 diabetes and nephropathy.  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   
7.
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   
8.
We reviewed the outcome of corpus callosal section in 64 adult and pediatric patients to identify factors associated with a good outcome: 48% of patients had a favorable outcome for overall seizure frequency. Improvement was noted in several seizure types and was most likely for drop attacks, particularly in the setting of a unilateral focal cerebral lesion or a true generalized epilepsy of Lennox-Gastaut type. Poor outcomes for drop attacks were more likely if there was associated severe intellectual handicap or bilateral independent spikes on interictal EEG. Complex partial seizures (CPS), most commonly of frontal lobe origin, also responded favorably. The complications of callosal section were usually mild and transient. New focal seizures occurred in only 2 patients and were not as frequent or disabling as preoperative seizure types. A worthwhile improvement in seizure outcome was achieved by completion of the callosotomy in 6 of 10 patients with unsatisfactory results from anterior callosotomy.  相似文献   
9.
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   
10.
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   
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