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51.

Background

Exposure to mustard gas frequently results in long-term respiratory complications. However the factors which drive the development and progression of these complications remain unclear. The Renin Angiotensin System (RAS) has been implicated in lung inflammatory and fibrotic responses. Genetic variation within the gene coding for the Angiotensin Converting Enzyme (ACE), specifically the Insertion/Deletion polymorphism (I/D), is associated with variable levels of ACE and with the severity of several acute and chronic respiratory diseases. We hypothesized that the ACE genotype might influence the severity of late respiratory complications of mustard gas exposure.

Methods

208 Kurdish patients who had suffered high exposure to mustard gas, as defined by cutaneous lesions at initial assessment, in Sardasht, Iran on June 29 1987, underwent clinical examination, spirometric evaluation and ACE Insertion/Deletion genotyping in September 2005.

Results

ACE genotype was determined in 207 subjects. As a continuous variable, FEV1 % predicted tended to be higher in association with the D allele 68.03 ± 20.5%, 69.4 ± 21.4% and 74.8 ± 20.1% for II, ID and DD genotypes respectively. Median FEV1 % predicted was 73 and this was taken as a cut off between groups defined as having better or worse lung function. The ACE DD genotype was overrepresented in the better spirometry group (Chi2 4.9 p = 0.03). Increasing age at the time of exposure was associated with reduced FEV1 %predicted (p = 0.001), whereas gender was not (p = 0.43).

Conclusion

The ACE D allele is associated with higher FEV1 % predicted when assessed 18 years after high exposure to mustard gas.  相似文献   
52.

Apigenin, as a natural flavonoid present in several plants is characterized with potential anticancer, antioxidant, and anti-inflammatory properties. Recent studies proposed that apigenin affects depression disorder through unknown mechanistic pathways. The effects of apigenin’s anti-depressive properties on streptozocin-mediated depression have been investigated through the evaluation of behavioral tests, oxidative stress, cellular energy homeostasis and inflammatory responses. The results demonstrated anti-depressive properties of apigenin in behavioral test including forced swimming and splash tests and oxidative stress biomarkers such as reduced glutathione, lipid peroxidation, total antioxidant power and coenzyme Q10 levels. Apigenin, also, demonstrated its regulatory potency in cellular energy homeostasis and immune system gene expression through inhibiting Nlrp3 and Tlr4 overexpression. Furthermore, failure in energy production as the key factor in various psychiatric disorders was reversed by apigenin modulating effect on AMPK gene expression. Overall, 20 mg/kg of apigenin was recognized as the dose suitable for minimizing the undesirable adverse effects in the STZ-mediated depression model proposed in this study. Our data suggested that apigenin could be able to adjust behavioral dysfunction, biochemical biomarkers and recovered cellular antioxidant level in depressed animals. The surprising results were achieved by raise in COQ10 level, which could regulate the overexpression of the AMPK gene in stressful conditions. The regulatory effect of apigenin in inflammatory signaling pathways such as Nlrp3, and Tlr4 gene expression was studied at the surface part of the hippocampus.

  相似文献   
53.
Extremophiles - This work presents an evaluation of batch, fed-batch, and sequential batch cultivation techniques for production of R. marinus DSM 16675 and its exopolysaccharides (EPSs) and...  相似文献   
54.
55.
Somatic cloning in cattle is associated with impaired embryo development, caused by inappropriate epigenetic reprogramming during embryogenesis; however, there is a paucity of data regarding gene expression at the critical elongation and peri-implantation stages. The objective of the present study was to identify genes differentially expressed in bovine cloned embryos at Day 17 of development (Day 0 = day of nucleus transfer or IVF). Day 7 blastocysts (Hand Made Cloned or IVP) were transferred to recipient cattle and collected at Day 17. The efficiency of recovery of elongated embryos was similar, however cloned embryos elongated less than IVP embryos (91.8 ± 45.8 vs. 174 ± 50 mm) and fewer had embryonic discs (63 vs. 83%). Qualitative and quantitative PCR detected expression of OCT4, NANOG, IFNtau, EOMES, FGF4, SOX2, and CDX2 in all IVP embryos. In most cloned embryos, NANOG and FGF4 were absent (verified by qPCR); NANOG, EOMES, and FGF4 were underexpressed, whereas IFNtau was overexpressed in cloned embryos. Based on qPCRs, other genes, i.e., SPARC, SNRB1, and CBPP22, were down-regulated in cloned embryos, whereas HSP70 and TDKP1 were overexpressed. In bovine microarrays, 47 genes (3.6%) were deregulated in cloned embryos, including several involved in trophoblast growth and differentiation. In conclusion, we inferred that these data were indicative of incomplete epigenetic reprogramming after cloning; this could lead to aberrant gene expression and subsequently early pregnancy loss. There was an apparent association between incomplete morphological elongation and aberrant reprogramming of a subset of genes critical for early embryonic development.  相似文献   
56.
Wild populations of Fritillaria imperialis L. are facing extinction and need urgent conservation. This paper presents an efficient system for in vitro direct bulblet regeneration of these populations by petal culturing of flower buds. Petals at different developmental stages, green-closed flower bud (before nectar secretion) and red-closed flower bud (beginning of nectar secretion), were used as explants, and the effects of various proportions of cytokinin to auxin on direct bulblet regeneration pathway were evaluated. More explants switched on direct regeneration pathway in combination of auxins (0.6 mg l−1 NAA + 0.4 mg l−1 IAA) with higher level of cytokinin (1 mg l−1 BAP). In contrast, auxins (0.6 mg l−1 NAA + 0.4 mg l−1 IAA) with lower level of cytokinin (0.1 mg l−1 BAP) produced more bulblets per regenerated explant. In green-closed flower bud stage, direct bulblets regenerated from the end of petal where it was connected to the receptacle, while nectar secretion site was the place of bulblet formation in red-closed flower bud stage. In addition, genotype-dependency of direct bulblet regeneration pathway was investigated by using two different wild populations of Fritillaria imperialis. This plant regeneration procedure was applicable to different Fritillaria genotypes and regenerated bulblets were normal.  相似文献   
57.
Thrombolytic therapy by plasminogen activators (PAs) has been a main goal in the treatment of acute myocardial infarction. Despite improved outcomes of currently available thrombolytic therapies, all these agents have different drawbacks that may result in less than optimal outcomes. In order to make tissue plasminogen activator (tPA) more potent, while being more resistant to plasminogen activator inhibitor-1 (PAI-1) and having a higher affinity to fibrin, a new chimeric-truncated form of tPA (CT tPA) was designed and expressed in Pichia pastoris. This novel variant consists of a finger domain of Desmoteplase, an epidermal growth factor (EGF) domain, a kringle 1 (K1) domain, a kringle 2 (K2) domain, in which the lysine binding site (LBS) was deleted, and a protease domain, where the four amino acids lysine 296, arginine 298, arginine 299, and arginine 304 were substituted by aspartic acid. The chimera CT tPA showed 14-fold increase in its activity in the presence of fibrin compared to the absence of fibrin. Furthermore, CT tPA showed about 10-fold more potency than commercially available full-length tPA (Actylase®) and provided 1.2-fold greater affinity to fibrin. A residual activity of only 68 % was observed after incubation of Actylase® with PAI-1, however, 91 % activity remained for CT tPA. These promising findings suggest that the novel CT tPA variant might be an acceptable PA with superior characteristics and properties.  相似文献   
58.

Background

Measurement-unit conflicts are a perennial problem in integrative research domains such as clinical meta-analysis. As multi-national collaborations grow, as new measurement instruments appear, and as Linked Open Data infrastructures become increasingly pervasive, the number of such conflicts will similarly increase.

Methods

We propose a generic approach to the problem of (a) encoding measurement units in datasets in a machine-readable manner, (b) detecting when a dataset contained mixtures of measurement units, and (c) automatically converting any conflicting units into a desired unit, as defined for a given study.

Results

We utilized existing ontologies and standards for scientific data representation, measurement unit definition, and data manipulation to build a simple and flexible Semantic Web Service-based approach to measurement-unit harmonization. A cardiovascular patient cohort in which clinical measurements were recorded in a number of different units (e.g., mmHg and cmHg for blood pressure) was automatically classified into a number of clinical phenotypes, semantically defined using different measurement units.

Conclusions

We demonstrate that through a combination of semantic standards and frameworks, unit integration problems can be automatically detected and resolved.
  相似文献   
59.
Hepatitis delta virus (HDV) replication and packaging require interactions between the unbranched rodlike structure of HDV RNA and hepatitis delta antigen (HDAg), a basic, disordered, oligomeric protein. The tendency of the protein to bind nonspecifically to nucleic acids has impeded analysis of HDV RNA protein complexes and conclusive determination of the regions of HDAg involved in RNA binding. The most widely cited model suggests that RNA binding involves two proposed arginine-rich motifs (ARMs I and II) in the middle of HDAg. However, other studies have questioned the roles of the ARMs. Here, binding activity was analyzed in vitro using HDAg-160, a C-terminal truncation that binds with high affinity and specificity to HDV RNA segments in vitro. Mutation of the core arginines of ARM I or ARM II in HDAg-160 did not diminish binding to HDV unbranched rodlike RNA. These same mutations did not abolish the ability of full-length HDAg to inhibit HDV RNA editing in cells, an activity that involves RNA binding. Moreover, only the N-terminal region of the protein, which does not contain the ARMs, was cross-linked to a bound HDV RNA segment in vitro. These results indicate that the amino-terminal region of HDAg is in close contact with the RNA and that the proposed ARMs are not required for binding HDV RNA. Binding was not reduced by mutation of additional clusters of basic amino acids. This result is consistent with an RNA-protein complex that is formed via numerous contacts between the RNA and each HDAg monomer.  相似文献   
60.
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