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61.
Molecular Biology Reports - Coronary artery disease (CAD) which is a complex cardiovascular disease is the leading cause of death worldwide. The changing prevalence of the disease in different...  相似文献   
62.
Mare S  Penugonda S  Robinson SM  Dohgu S  Banks WA  Ercal N 《Peptides》2007,28(7):1424-1432
The amyloid hypothesis states that amyloid beta protein (Abeta) plays a major causal role in the onset of Alzheimer's disease. Toxicity of Abeta can be modified by metal ions. Two mechanisms by which such Abeta and metal ions could interact are by enhanced oxidative stress or by altered fibrillation. Specifically, Abeta fibrillation is increased by aluminum (Al) and copper (Cu) and Al also increases Abeta uptake into brain. Here, we determined whether chelation with Cu would alter uptake of the human or rat 1-42 form of Abeta (Abeta42) by brain or alter Abeta-induced oxidative stress in an immortalized line of rat brain endothelial cells (RBE4). We found that Cu enhanced cytotoxicity of rat, but not of human Abeta, had no effect on glutathione (GSH) or cysteine (CYS) levels. Cu significantly decreased homocysteine (HCYS) levels when complexed with Abeta. Cu chelation did not alter Abeta uptake into brain or other tissues (except for kidney) or alter clearance from blood or brain in vivo, but did increase efflux in an in vitro model of the blood-brain barrier (BBB). Chelation to Cu also impaired the capillary to brain transport of Abeta, an effect opposite to that previously found for chelation of Abeta to Al. These results show that metal ions have varied effects on Abeta uptake by brain and that Cu could be protective against the neurotoxic effects of circulating Abeta.  相似文献   
63.
Thiocyl (sodium thiosalicylate) belongs to a salicylate group of drugs, thus it has analgesic, antipyretic and anti-inflammatory effects. It possesses metal chelating function because it also belongs to a thiol-containing group of compounds which are well-known chelators. The studies of our research group showed that thiocyl is a promising chelator of lead poisoning due to its antioxidant and metal-chelating abilities. To the best of our knowledge, no methods were currently available for measuring thiocyl in biological samples. Therefore, we developed a reversed-phase HPLC method using fluorescence detection (lambdaex = 365 nm, lambdaem = 445 nm) with a one-step derivatizing reaction between thiocyl and a derivatizing agent-ThioGlo 3 (9-acetoxy-2-(4-(2, 5-dihydro-2,5-dioxo-1H-pyrrol-1-yl)pyenyl)-3-oxo-3H-naphtho[2,1-b]pyran). Most biological thiols (such as N-acetylcysteine (NAC), cysteine (CYS), glutathione (GSH) and homocysteine (HCYS)) do not interfere with the detection of thiocyl by using this technique. The linear range of its calibration curve was determined to be 25-2500 nM, and the detection limit of thiocyl was found to be 3 nM with 20 microL injection volume. The coefficients of variation (CV) for within-run precision and between-run precision ranged from 0.93 to 7.21%. This assay proved to be a rapid, sensitive and simple method for determining thiocyl in biological samples.  相似文献   
64.
Fraser syndrome is a rare autosomal recessive genetic disorder characterized by cryptophthalmus, variable expression of cutaneous syndactyly of fingers and toes, genital ambiguity and renal agenesis/dysgenesis. We present here molecular and clinical findings of four fetuses with FS from two families. Molecular genetic studies in the two families revealed mutations in FRAS1 gene allowing better genetic counselling and subsequent prenatal diagnosis in one of the two families. In family one, a nonsense mutation (c.3730C>T, p.R1244X) previously described in a Polish patient was found. In family two a novel nonsense mutation previously not known was detected (c.370C>T, p.R124X). PGD is planned for family 1.  相似文献   
65.
The objectives of this research are the assessment of secondary effluents (SEs) quality by evaluating chemical parameters and biomarkers. For this purpose, MDA and GSH levels were determined by spectrofotometer. SOD, CAT, and GPX activities were determined by using ELISA kit in the groups of control and the groups exposed to SE. The level of MDA and the activities of SOD in Gammarus pulex vary depending on the exposure time. GSH levels and GSH-PX activities increased in G. pulex exposed to the effluent compared to the control during 24 h and 96 h. CAT activities were in SE group were found lower than the control in G. pulex during 24 h and 96 h. Current experimental results show that SOD, CAT, GPX activities, and GSH and MDA levels in G. pulex are sensitive and appropriate responses for assess the effects of anthropogenic contaminants on the aquatic ecosystems, particularly effluent complex mixtures.  相似文献   
66.
Nuran Ekici 《Biologia》2014,69(10):1323-1330
In this study, Gagea villosa (Bieb.) Duby was investigated by using light microscopy methods in cytological and cytoembryological respects. Anthers were tetrasporangiate. Anther wall was formed with an epidermis, endothecium, middle layer and tapetum. Tapetum was glandular type and it began to degenerate when microspores released from tetrads. Tapetum cells generally have one or two nuclei. Mitosis seen in tapetum cells was generally normal but micronuclei were found in some of them. Fibrous thickenings were determined in endothecium. Microsporogenesis and pollen mitosis were generally regular. Cytokinesis was successive type. Meiosis in pollen mother cells was asynchronous in one anther locus. Mature pollen grains were 2-celled. Pollen sterility was found to be 24%. Some of the fertile pollen grains, smaller than the normal were seen at the end of the pollen mitosis. Microgametophyte development was examined in vivo and in vitro. Germination ratio of pollen grains in vitro was 4%. Generally swollen pollen tube tips and weak development of some curled pollen tubes were seen. Callose plug formation was seen only in vivo pollen tube growth.  相似文献   
67.
The aim of this study was to investigate the respiratory function disorders that could be related to dust exposure during the production of copper mine in copper mineworkers (CMWs). The study included 75 male CMWs (mean age, 32.0 ± 7.1 years, 58.6% smokers) and 75 male age- and smoking status-matched healthy control subjects. Serum Cu level was significantly higher in the CMW group (0.80 ± 0.62 μg/ml) than the control group (0.60 ± 0.39 μg/ml) (p = 0.017). Significant negative correlations were found between serum Cu level and forced expiratory volume in first second (r = −0.600; p < 0.001) and between serum Cu level and forced vital capacity (r = −0.593; p = <0.001) in CMWs. Serum Cu level was significantly higher in the restrictive type pulmonary function disorders group (1.36 ± 0.62 μg/ml) than obstructive type (0.90 ± 0.55 μg/ml) and normal pulmonary function pattern group (0.53 ± 0.43 μg/ml) (p < 0.001). Patients with radiological parenchymal abnormalities had significantly higher serum copper levels than those without abnormalities (1.53 ± 0.52 vs. 0.71 ± 0.52 μg/ml, respectively; p = 0.002). In conclusion, result of the study has shown a negative association between pulmonary functions disorders and radiological abnormalities and serum Cu levels in CMWs.  相似文献   
68.
69.
Glioblastoma (GBM) is an aggressive and lethal cancer, accounting for the majority of primary brain tumors in adults. GBMs are characterized by large and small alterations in genes that control cell growth, apoptosis, angiogenesis, and invasion. Epigenetic alterations also affect the expression of cancer genes, either alone or in combination with genetic mechanisms. The current evidence suggests that hypermethylation of promoter CpG islands is a common epigenetic event in a variety of human cancers. A subset of GBMs is also characterized by a locus-specific and genome-wide decrease in DNA methylation. Epigenetic alterations are important in the molecular pathology of GBM. However, there are very limited data about these epigenetic alterations in GBM. Alterations in promoter methylations are important to understand because histone deacetylases are targets for drugs that are in clinical trial for GBMs. The aim of the current study was to investigate whether the promoter hypermethylation of putative tumor suppressor genes was involved in GBM. We examined the methylation status at the promoter regions of GATA6, MGMT, and FHIT using the methylation-specific polymerase chain reaction in 61 primary GBMs. Our results reveal that there is no promoter hypermethylation of FHIT in the examined GBM tissue specimens. In contrast, the promoter hypermethylation of GATA6 and MGMT was detected in 42.8 and 11.11% of GBMs, respectively. The frequency of MGMT promoter hypermethylation was low in the group of patients we evaluated. In conclusion, our study demonstrates that promoter hypermethylation of MGMT is a common event in GBMs, whereas GATA6 is epigenetically affected in GBMs. Furthermore, inactivation of FHIT by epigenetic mechanisms in GBM may not be associated with brain tumorigenesis.  相似文献   
70.
Intellectual disability inherited in an autosomal-recessive fashion represents an important fraction of severe cognitive-dysfunction disorders. Yet, the extreme heterogeneity of these conditions markedly hampers gene identification. Here, we report on eight affected individuals who were from three consanguineous families and presented with severe intellectual disability, absent speech, shy character, stereotypic laughter, muscular hypotonia that progressed to spastic paraplegia, microcephaly, foot deformity, decreased muscle mass of the lower limbs, inability to walk, and growth retardation. Using a combination of autozygosity mapping and either Sanger sequencing of candidate genes or next-generation exome sequencing, we identified one mutation in each of three genes encoding adaptor protein complex 4 (AP4) subunits: a nonsense mutation in AP4S1 (NM_007077.3: c.124C>T, p.Arg42(?)), a frameshift mutation in AP4B1 (NM_006594.2: c.487_488insTAT, p.Glu163_Ser739delinsVal), and a splice mutation in AP4E1 (NM_007347.3: c.542+1_542+4delGTAA, r.421_542del, p.Glu181Glyfs(?)20). Adaptor protein complexes (AP1-4) are ubiquitously expressed, evolutionarily conserved heterotetrameric complexes that mediate different types of vesicle formation and the selection of cargo molecules for inclusion into these vesicles. Interestingly, two mutations affecting AP4M1 and AP4E1 have recently been found to cause cerebral palsy associated with severe intellectual disability. Combined with previous observations, these results support the hypothesis that AP4-complex-mediated trafficking plays a crucial role in brain development and functioning and demonstrate the existence of a clinically recognizable syndrome due to deficiency of the AP4 complex.  相似文献   
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