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91.
ABSTRACT. By use of a monoclonal antibody directed against purified lectin from the sponge Geodia cydonium it was demonstrated that the mucocysts of Tetrahymena pyriformis contain a substance immunologically similar to that found in G. cydonium . In extracts of T. pyriformis the monoclonal antibody recognizes a 36 kDa protein; binding could be abolished by adsorption of the antibody with (i) crude extract, (ii) purified lectin from G. cydonium and (iii) a 29 aa long peptide. In addition the data show that 10-6 M of insulin causes first the release of mucocyst material, which reacts with the lectin antibody, and second its subsequent redistribution on the surface of the somatic cilia and the oral field.  相似文献   
92.
In order to determine whether there is a genetic component to hip or knee joint failure due to idiopathic osteoarthritis (OA), we invited patients (probands) undergoing hip or knee arthroplasty for management of idiopathic OA to provide detailed family histories regarding the prevalence of idiopathic OA requiring joint replacement in their siblings. We also invited their spouses to provide detailed family histories about their siblings to serve as a control group. In the probands, we confirmed the diagnosis of idiopathic OA using American College of Rheumatology criteria. The cohorts included the siblings of 635 probands undergoing total hip replacement, the siblings of 486 probands undergoing total knee replacement, and the siblings of 787 spouses. We compared the prevalence of arthroplasty for idiopathic OA among the siblings of the probands with that among the siblings of the spouses, and we used logistic regression to identify independent risk factors for hip and knee arthroplasty in the siblings. Familial aggregation for hip arthroplasty, but not for knee arthroplasty, was observed after controlling for age and sex, suggesting a genetic contribution to end-stage hip OA but not to end-stage knee OA. We conclude that attempts to identify genes that predispose to idiopathic OA resulting in joint failure are more likely to be successful in patients with hip OA than in those with knee OA.  相似文献   
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High-performance liquid chromatographic analyses of chondroitin lyase AC or ABC hydrolysates revealed unexpected high content of material coeluting with the nonsulfated disaccharide 2-acetamido-2-deoxy-3-O-(β-d-gluco-4-enepyranosyl uronic acid)-d-galactose. Incubation of a commercial preparation of the 6-sulfated disaccharide, 2-acetamido-2-deoxy-3-O-(β-d-gluco-4-enepyranosyl uronic acid)-6-O-sulfo-d-galactose with “enriched Tris buffer” generated material coeluting with nonsulfated disaccharide. The amount of material exhibiting this anomalous chromatographic behavior was proportional to the amount of 6-sulfated disaccharide added to the incubation mixture. This suggested a precursor/product relationship between the 6-sulfated disaccharide and the anomalous peak. The result was specific for the 6-sulfated disaccharide: incubation of the 4-sulfated disaccharide, 2-acetamido-2-deoxy-3-O-(β-d-gluco-4-enepyranosyl uronic acid)-4-O-sulfo-d-galactose, with enriched Tris buffer did not generate material with anomalous chromatographic properties. When [35S]sulfate labeled cartilage glycosaminoglycans were hydrolyzed with chondroitin lyases, some of the radioactivity coeluted with the nonsulfated disaccharide. Thus, buffer-induced modification of 6-sulfated disaccharide was not caused by hydrolysis of ester sulfate. Although the proportion of the 6-sulfated disaccharide which was recovered in the anomalous peak was constant for incubations done simultaneously, incubations done at different times gave variable results. Thus, control incubations of 6-sulfated disaccharide with chondroitinase buffer must be included with each reaction series to allow correction for the proportion of the material eluting with nonsulfated disaccharide which is actually 6-sulfated.  相似文献   
96.
Inducible Cre recombination is a powerful technology that allows for spatial and temporal modulation of gene expression in vivo. Diseases of the cardiac conduction system (CCS) pose a significant clinical burden but are not currently well understood at the molecular level. To enable inducible recombination in the murine CCS, we created a minK:CreERT(2) bacterial artificial chromosome (BAC) transgenic mouse line. Cre activity is present after tamoxifen administration in the atrioventricular (AV) node, AV bundle, and bundle branches of adult transgenic mice. We anticipate that by enabling inducible recombination specifically in the AV node, bundle, and bundle branches, minK:CreERT(2) BAC transgenic mice will prove useful in advancing our understanding of CCS disease and function.  相似文献   
97.
Hypoplastic left heart syndrome(HLHS) refers to the abnormal development of the left-sided cardiac structures, resulting in obstruction to blood flow from the left ventricular outflow tract. In addition, the syndrome includes underdevelopment of the left ventricle, aorta, and aortic arch, as well as mitral atresia or stenosis. HLHS has been reported to occur in approximately 0.016 to 0.036% of all live births. Newborn infants with the condition generally are born at full term and initially appear healthy. As the arterial duct closes, the systemic perfusion becomes decreased, resulting in hypoxemia, acidosis, and shock. Usually, no heart murmur, or a non-specific heart murmur, may be detected. The second heart sound is loud and single because of aortic atresia. Often the liver is enlarged secondary to congestive heart failure. The embryologic cause of the disease, as in the case of most congenital cardiac defects, is not fully known. The most useful diagnostic modality is the echocardiogram. The syndrome can be diagnosed by fetal echocardiography between 18 and 22 weeks of gestation. Differential diagnosis includes other left-sided obstructive lesions where the systemic circulation is dependent on ductal flow (critical aortic stenosis, coarctation of the aorta, interrupted aortic arch). Children with the syndrome require surgery as neonates, as they have duct-dependent systemic circulation. Currently, there are two major modalities, primary cardiac transplantation or a series of staged functionally univentricular palliations. The treatment chosen is dependent on the preference of the institution, its experience, and also preference. Although survival following initial surgical intervention has improved significantly over the last 20 years, significant mortality and morbidity are present for both surgical strategies. As a result pediatric cardiologists continue to be challenged by discussions with families regarding initial decision relative to treatment, and long-term prognosis as information on long-term survival and quality of life for those born with the syndrome is limited.  相似文献   
98.
1 The composition of pome fruit orchard inhabiting spider assemblages was investigated at different geographical scales (Holarctic, European, inter- and intraregional levels within Hungary) using previous faunistic studies and data collected in Hungary between 1995 and 1997. Samples in Hungary were taken from the canopy and herb layer of apple and pear orchards in five markedly different fruit-growing regions by beating and sweep-netting methods. 2 The composition of canopy spider assemblages of apple orchards was analysed for the Holartic region and found to be determined by latitude at family level, and by the main zoogoegraphical regions at genus level. At the European scale, both the genus and species composition changed along a north–south gradient. 3 A comparison among apple and pear orchards located in different regions in Hungary, showed that both foliage- and grass-dwelling spider assemblages varied considerably in species composition and dominance order. 4 Within the same region, both the foliage- and grass-dwelling spider assemblages showed moderate differences in apple and pear orchards submitted to different treatments. Although the assemblages of spiders inhabiting the canopy and the herbaceous layer can be unambiguously distinguished, some overlap still occurs. 5 We conclude that the composition of spider assemblages is basically determined by geographical location. Although both pesticide treatments and available prey densities can influence the population of spiders, such factors are of moderate importance when compared with the effect of regionality, even when considered at smaller scale. However, most members of the family Theridiidae and the large orb-weavers (Araneidae) decreased considerably in treated plots. Scale-specific differences are thus relevant in determining the composition of prey–predator systems in orchards, and should be taken into account when designing integrated pest management (IPM) programs for apple and pear orchards.  相似文献   
99.
Plasmodium vivax is the most widespread parasite causing malaria, being especially prevalent in the Americas and Southeast Asia. Children are one of the most affected populations, especially in highly endemic areas. However, there are few studies evaluating the therapeutic response of infants with vivax malaria. This study retrospectively evaluated the parasitaemia clearance in children diagnosed with vivax malaria during the first five days of exclusive treatment with chloroquine (CQ). Infants aged less than six months old had a significantly slower parasitaemia clearance time compared to the group of infants and children between six months and 12 years old (Kaplan-Meier survival analysis; Wilcoxon test; p = 0.004). The impaired clearance of parasitaemia in younger children with vivax malaria is shown for the first time in Latin America. It is speculated that CQ pharmacokinetics in young children with vivax malaria is distinct, but this specific population may also allow the detection of CQ-resistant parasites during follow-up, due to the lack of previous immunity.  相似文献   
100.
Inflammation plays an important role in ischemic stroke and in humans IL-10 may have a beneficial effect in stroke. We mucosally administered myelin oligodendrocyte glycoprotein (MOG) 35-55 peptide to C57BL/6 mice before middle cerebral artery occlusion (MCAO) to induce an anti-inflammatory T cell response directed at CNS myelin. Nasal and oral administration of MOG(35-55) peptide decreased ischemic infarct size at 24 and 72 h after MCAO surgery. Nasal MOG(35-55) peptide was most efficacious and reduced infarct size by 70% at 24 h and by 50% at 72 h (p 相似文献   
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