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861.
BmR1 recombinant antigen has previously been shown to demonstrate high sensitivity and specificity in the serological diagnosis of brugian filariasis in humans. In this study, the pattern of recognition of antibody to BmR1 during Brugia malayi infection was investigated by employing Meriones unguiculatus as the experimental model. Thirty two gerbils were infected subcutaneously with 120 L(3); and two control groups each comprising 25 animals were employed. ELISA using BmR1 was used to detect filaria-specific IgG antibodies elicited by the gerbils; using sera collected from the day 1 until day 150 post-inoculation (p.i.). The results showed that BmR1 detected B. malayi infection in gerbils harboring adult worms irrespective of the presence of circulating microfilaria, and was exemplified by positive ELISA results in nine a microfilaraemic animals that harbored live adult worms. The initial time of the antibody recognition was at day 8 p.i. and the antibody titre showed some correlation with adult worm burden.  相似文献   
862.
863.

Background  

It is known that aurora B, a chromosomal passenger protein responsible for the proper progression of mitosis and cytokinesis, is overexpressed throughout the cell cycle in cancer cells. Overexpression of aurora B produced multinuclearity and induced aggressive metastasis, suggesting that overexpressed aurora B has multiple functions in cancer development. However, the detailed dynamics and functions of overexpressed aurora B are poorly understood.  相似文献   
864.
865.
Wolfram syndrome is an autosomal recessive neuro-degenerative disorder associated with juvenile onset non-autoimmune diabetes mellitus and progressive optic atrophy. The disease has been attributed to mutations in the WFS1 gene, which codes for a protein predicted to possess 9-10 transmembrane segments. Little is known concerning the function of the WFS1 protein (wolframin). Endoglycosidase H digestion, immunocytochemistry, and subcellular fractionation studies all indicated that wolframin is localized to the endoplasmic reticulum in rat brain hippocampus and rat pancreatic islet beta-cells, and after ectopic expression in Xenopus oocytes. Reconstitution of wolframin from oocyte membranes into planar lipid bilayers demonstrated that the protein induced a large cation-selective ion channel that was blocked by Mg2+ or Ca2+. Inositol triphosphate was capable of activating channels in the fused bilayers that were similar to channel components induced by wolframin expression. Expression of wolframin also increased cytosolic calcium levels in oocytes. Wolframin thus appears to be important in the regulation of intracellular Ca2+ homeostasis. Disruption of this function may place cells at risk to suffer inappropriate death decisions, thus accounting for the progressive beta-cell loss and neuronal degeneration associated with the disease.  相似文献   
866.
867.
Recent developments in technology and soil science have drawn particular attention to peatlands and their behaviour, properties and utilisation. Further, characteristics of peat are very important in evaluating it as a plant growth medium. The objective of this study was to characterise a number of samples collected from different depths of five different profiles of Yeni?a?a peat (carex) by measuring the organic carbon, total nitrogen, and extinction values (Er) of their humic acid fractions (HAs) in comparison with decomposition degrees. Peat samples having a high decomposition degree were near to the Er45 axis in the ordinate and had high Er67 values, whereas peats with low decomposition degree were far from the Er45 axis and had low Er67 values.  相似文献   
868.
Available information on the fate and insulinotropic action of L-alanine in isolated pancreatic islets is restricted to data collected in obese hyperglycemic mice. Recent data, however, collected mostly in tumoral islet cells of either the RINm5F line or BRIN-BD11 line, have drawn attention to the possible role of Na(+) co-transport in the insulinotropic action of L-alanine. In the present study conducted in islets prepared from normal adult rats, L-alanine was found (i) to inhibit pyruvate kinase in islet homogenates, (ii) not to affect the oxidation of endogenous fatty acids in islets prelabelled with [U-14C]palmitate, (iii) to stimulate 45Ca uptake in islets deprived of any other exogenous nutrient, and (iv) to augment insulin release evoked by either 2-ketoisocaproate or L-leucine, whilst failing to significantly affect glucose-induced insulin secretion. The oxidation of L-[U-14C]alanine was unaffected by D-glucose, but inhibited by L-leucine. Inversely, L-alanine decreased the oxidation of D-[U-14C]glucose, but failed to affect L-[U-14C]leucine oxidation. It is concluded that the occurrence of a positive insulinotropic action of L-alanine is restricted to selected experimental conditions, the secretory data being compatible with the view that stimulation of insulin secretion by the tested nutrient(s) reflects, as a rule, their capacity to augment ATP generation in the islet B cells. However, the possible role of Na(+) co-transport in the secretory response to L-alanine cannot be ignored.  相似文献   
869.
Epileptic encephalopathies are genetically heterogeneous disorders which leads to epilepsy and cause neurological disorders. Seizure threshold 2 (SZT2) gene located on chromosome 1p34.2 encodes protein mainly expressed predominantly in the parietal and frontal cortex and dorsal root ganglia in the brain. Previous studies in mice showed that mutation in this gene can confers low seizure threshold, enhance epileptogenesis and in human may leads to facial dysmorphism, intellectual disability, seizure and macrocephaly. Objective of this study was to find out novel gene or novel mutation related to the gene phenotype. We have identified a large consanguineous Saudi family segregating developmental delay, intellectual disability, epilepsy, high forehead and macrocephaly. Exome sequencing was performed in affected siblings of the family to study the novel mutation. Whole exome sequencing data analysis, confirmed by subsequent Sanger sequencing validation study. Our results showed a novel homozygous mutation (c.9368G>A) in a substitution of a conserved glycine residue into a glutamic acid in the exon 67 of SZT2 gene. The mutation was ruled out in 100 unrelated healthy controls. The missense variant has not yet been reported as pathogenic in literature or variant databases. In conclusion, the here detected homozygous SZT2 variant might be the causative mutation that further explain epilepsy and developmental delay in this Saudi family.  相似文献   
870.
Chronic rhinosinusitis with nasal polyposis is a chronic inflammatory disease of the respiratory mucosa of the nasal cavity and paranasal sinuses. The aim of this study was investigate the effect of nasal obstruction related to chronic rhinosinusitis with nasal polyposis on cognitive functions. Patients with chronic rhinosinusitis with nasal polyposis causing bilateral total or near total nasal obstruction were enrolled in the study. Symptoms of nasal congestion, loss of smell, postnasal drip, headaches, snoring, concentration difficulties and blunted affect were evaluated by Visual Analog Scale. Brief symptom inventory test, Stroop test, visual aural digit span, serial digit learning test and P300 test were used to evaluate cognitive functions. Three months after treatment, the tests done before surgery were repeated and the results were compared. A total of 30 patients were included in the study. On the Visual Analog Scale, all symptoms showed significant postoperative improvement in all patients (p?<?0.001 for all symptoms). Preoperative nasal congestion accompanied with impaired concentration were detected in 27 patients (90%), and these symptoms recovered in all these patients after treatment (p?=?0.035) (correlation coefficient 0.4). Only 22 patients completed the neuropsychological tests. The mean preoperative Stroop test (23.16?±?5.30), visual aural digit span test (24.68?±?3.52), and serial digit learning test (16.18?±?5.35) scores were showed significant improvement compared with mean postoperative Stroop test (21.12?±?5.69), visual aural digit span test (26.45?±?2.98), and serial digit learning test (19.31?±?4.47) scores (p?=?0.047, p?=?0.022, p?=?0.005 respectively). The postoperative P300 latency values improved in 19 (63%) patients. The preoperative and postoperative latency values for P300 showed a significant difference (p?=?0.029), whereas the preoperative and postoperative amplitude values for P300 did not differ (p?=?0.096). In conclusion, the results of this study indicate that chronic rhinosinusitis with nasal polyposis (CRSwNP) has negative effects on cognitive functions, such as the ability to focus and maintain concentration. These cognitive functions improve after the patients undergo endoscopic sinus surgery to treat their CRSwNP.  相似文献   
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