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21.
Wolfram syndrome (WS) is an autosomal recessive neurodegenerative disorder characterised by early onset diabetes mellitus and progressive optic atrophy, as well as other clinical features such as deafness, diabetes insipida, renal tract abnormalities and diverse psychiatric illnesses. A gene responsible for WS was identified in 4p16.1 (WFS1). It encodes a putative 890 amino acid transmembrane protein expressed in a wide spectrum of tissues. Recently, a new locus for WS has been located on 4q22-24, providing additional evidence for the genetic heterogeneity of this syndrome. We have studied the presence of WFS1 variants in three groups of individuals: patients with diabetes mellitus, patients with deafness and patients with both conditions. A fourth group of healthy subjects was used as control. We have identified a total of 18 nucleotide changes in the WFS1 gene: three mutations and 15 polymorphisms. Six of these changes were previously undescribed. Four of the 15 polymorphisms studied among the patients group present statistical differences in the allelic and genotypic distribution when comparing affected vs control groups.  相似文献   
22.
We have investigated the genetic diversity of dengue type-1 (DEN-1) virus in Brazil. The full nucleotide sequences of three DEN-1 virus isolated from DEN fever (DF) and DEN hemorrhagic fever patients in northeastern Brazil in 1997 (BR/97) and one from a DF patient in the south of Brazil in 2001 (BR/01) were compared to that of the reference strain BR/90 obtained in the city of Rio de Janeiro in 1990. Sequence analysis showed that the structural proteins were remarkably conserved between all isolates. A total of 27 amino acid changes occurred throughout the non-structural proteins. Among them, nine amino acid substitutions were specific of BR/97 and BR/01 isolates, indicating that in situ evolution of these strains had occurred. Within the BR/97 and BR/01 samples, some amino acid substitutions have been previously identified in DEN-1 virus strains sequenced so far, suggesting that recombination events might have occurred.  相似文献   
23.
At its extrapelvic course the inferior gluteal a. is found to be strictly related to the sciatic n. This relationship has been described in a general way, emphasizing its medial localization in respect to the nerve. Clinicosurgical reports describe cases of aneurysms of the inferior gluteal a. on its extrapelvic course and subsequent compression at the nerve. In order to get further details on the relationship between these two structures, 80 gluteal regions from 40 cadavers of adult Brazilian individuals, 29 males and 11 females, were dissected. The inferior gluteal a. was found medial to the sciatic n. in 62 cases (77.5%); in the 18 remaining (22.5%) the trunk of the artery or one of its branches perforated the nerve. Of these, 14 (77.8%) were males and 4 (22.2%) females. This disposition was found 8 times (44.4%) on the right and 10 (55.6%) on the left side; was unilateral in 4 individuals (1 on the right and 3 on the left side) and bilateral in 7. The course of the inferior gluteal a. through the sciatic n. and/or the presence of aneurysms of this artery should be considered as a possible cause of nerve compression.  相似文献   
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BACKGROUND: Human metapneumovirus (hMPV) has been described as an etiologic agent of acute respiratory infections (ARI), mainly in pediatric patients. Viral isolation is difficult and has low sensitivity, and consequently RT-PCR assays are currently used for detection. OBJECTIVES: Detect hMPV in ARI in hospitalized children in Southern Brazil; standardize a RT-PCR for routine hMPV diagnosis; validate a positive control for molecular tests; and perform phylogenetics analyses. STUDY DESIGN: Nasopharyngeal aspirates (NPA) from 156 hospitalized children were studied. A conserved region of the nucleoprotein gene was cloned, characterized and used to standardize an RT-PCR assay. Phylogenetic analyses were performed. Clinical data were obtained from medical records. RESULTS: hMPV was detected in 6.4% of the samples. Dyspnea and wheezing were frequently reported symptoms and the most common diagnoses were bronchiolitis, acute respiratory insufficiency or laryngotracheobronchitis. Nucleotide sequence alignment revealed 97.7% identity with genotype A1 of hMPV. The detection limit of hMPV genomes by RT-PCR in clinical samples was 180 copies/microL. CONCLUSION: This is the first report of the detection and genetic characterization of hMPV infections in children with lower ARI in Southern Brazil.  相似文献   
26.
Dry extracts from the Eurasian plants, Ajuga turkestanica, Eurycoma longifolia, and Urtica dioica have been used as anabolic supplements, despite the limited scientific data on these effects. To assess their actions on early sarcopenia signs, male and female castrated mice were supplemented with lyophilized extracts of the three plants, isolated or in association (named TLU), and submitted to resistance exercise. Ovariectomy (OVX) led to body weight increase and non-high-density cholesterol (HDL) cholesterol elevation, which had been restored by exercise plus U. dioica extract, or by exercise and TLU, respectively. Orchiectomy (ORX) caused skeletal muscle weight loss, accompanied by increased adiposity, being the latter parameter reduced by exercise plus E. longifolia or U. dioica extracts. General physical activity was improved by exercise plus herbal extracts in either OVX or ORX animals. Exercise combined with TLU improved resistance to fatigue in OVX animals, though A. turkestanica enhanced the grip strength in ORX mice. E. longifolia or TLU also reduced the ladder climbing time in ORX mice. Resistance exercise plus herbal extracts partly altered gastrocnemius fiber size frequencies in OVX or ORX mice. We provide novel data that tested ergogenic extracts, when combined with resistance exercise, improved early sarcopenia alterations in castrated male and female mice.  相似文献   
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Ten male patients with chronic cocaine abuse received a single dose of the dopamine agonist apomorphine. Self-ratings of cocaine craving, depression, and anxiety decreased in response to apomorphine. Neuroendocrine response was consistent with central dopaminergic stimulation. Patients in the "craving" phase of the cocaine abuse cycle differed in behavioral but not neuroendocrine response to apomorphine from patients in the "crash" phase. Decrease in cocaine craving correlated with decrease in plasma homovanillic acid (pHVA). Total cocaine consumption correlated negatively with baseline prolactin and pHVA levels and inversely with peak change in prolactin following apomorphine. Patients had blunted neuroendocrine response to apomorphine in comparison to historical normal controls. Implications for the "dopamine" hypothesis of cocaine abuse are discussed.  相似文献   
29.
Two thousand consecutive children have been evaluated for suspected heart disease in a 27-month period. The main reasons for referral were: murmur (70%), precordial pain (9.5%), suspicion of arrhythmia (8.5%) and breathless (5%). Five hundred and six (25%) cases did not complete the investigation and the results were not computed. A final diagnosis was obtained based on the reason for referral and the main conclusions were: 1) a high incidence of normality was found: murmur (83%), pain (98%), arrhythmia (97%) and breathless (94%); 2) heart disease is unlikely when other referral reasons were analyzed; 3) 14% of the children were considered abnormal and the necessity of therapeutic procedures was 0.8%. A pediatric cardiology outpatient clinic in a public setting seems to be justifiable in the region, due to the high current demand.  相似文献   
30.
The authors report on a 45-day-old boy with a congenital intramedullary tumor with clinical manifestations since birth. Neurologic examination disclosed severe bilateral lower-limb hypotonia and diplegia, with exacerbated deep tendon reflexes and clonus associated with severe pain at manipulation. Further evaluation of this patient included screening for infections, computed tomographic scan, myelography, and somatosensory evoked potentials. The definite diagnosis was a solid holocord astrocytoma. This report discusses a rare disorder in the neonatal period and makes other medical practitioners aware of this diagnosis. Previously published literature is also reviewed.  相似文献   
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