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111.
Ashiq  Sana  Ashiq  Kanwal 《Biochemical genetics》2021,59(4):919-939

Although many studies have investigated the association of paraoxonase 1 (PON1) polymorphisms with coronary artery disease (CAD). However, the outcomes were not consistent and remain uncertain. Therefore, it is the need of the hour to analyze the available literature and evaluate the association of PON1 polymorphisms with the CAD. All the relevant studies published in the English language from January 1, 2000, up to September 20, 2020, were identified by searching through various electronic databases. The two researchers independently extracted the information. The data were analyzed by using the MetaGenyo program. The pooled odds ratio was used to find the associations between CAD and PON1 polymorphisms. In the final analysis, we include 10 studies regarding the association of PON1 polymorphisms (rs662 and rs854560) with CAD. Overall, the Q192R polymorphism increased the risk of CAD in the tested genetic models including the homozygote model: OR 1.35, CI 1.02–1.79; allelic model: OR 1.16, CI 1.00–1.33; dominant model: OR 1.25, CI 1.03–1.52. The L55M polymorphism does not significantly associated with CAD in all the tested genetic models including the homozygote model: OR 1.00 CI, 0.64–1.56; allelic model: OR 1.02, 95% CI 0.84–1.23; dominant model: OR 1.08, CI 0.89–1.31. Further analysis showed no publication bias exists in meta-analysis. Our findings suggested that rs662 in the coding region was significantly associated with the CAD however, rs854560 has no significant association with the disease. Nevertheless, in future, there is a need for more studies with a larger sample size which may provide a more definite conclusion.

Study Registration: PROSPERO registration number CRD42020202278

  相似文献   
112.
Floral induction by night interruption of Fuchsia hybrida cv. Lord Byron, a quantitative long-day plant with decussate phyllotaxis and an indeterminate flowering habit, altered neither the rate of leaf initiation nor the rate of leaf expansion; nor did flower initiation and development change the vegetative growth of the plants. This was diagnosed using plastochron duration and plastochron ratio measurements before, during, and after a 10-day induction period. A comparison between indeterminate and determinate flowering is made using these two parameters.  相似文献   
113.
Interleukin-2 (IL-2) and its receptor complex have become one of the most studied members of a growing family of protein hormones characterized by structural similarities in both ligands and their receptors. Structure-function studies of IL-2 have been complicated by the multimeric nature of its receptor. Two receptor subunits (55- and 75-kDa type I cell surface proteins) can participate to form the high affinity binding site. Although the IL-2 is apparently unique in some respects, similar subunit cooperativity has now been shown to be a common feature for other members of this receptor family. The availability of cell lines expressing the individual IL-2 receptor subunits has allowed detailed analysis of subunit binding characteristics. Results regarding the relationship of molecular recognition at each subunit to the mechanism of ligand binding at the high affinity site, however, have led to different interpretations. In this study we have employed previously prepared C-terminal IL-2 mutant proteins to examine receptor binding at all three classes using a variety of equilibrium and kinetic techniques. These results indicate that the high affinity IL-2 receptor complex includes the p55/p75 heterodimer prior to IL-2 binding and that both receptor subunits participate simultaneously in ligand capture.  相似文献   
114.
To investigate the potential molecular mediators of tissue-specific recruitment, we explored the influence of different cytokine challenges on gene expression regulation in five primary endothelial cells (ECs), representing two different phenotypes: iliac artery and aortic (macrovascular); lung, colon and dermal (microvascular). We challenged ECs with cytokines that elicit different patterns of inflammatory and immune responses in immune cells: tumor necrosis factor (TNF-alpha), interferon-gamma (IFN-gamma) or interleukin-4 (IL-4), and used microarrays containing approximately 40,000 unique cDNAs, to assess changes in differential gene expression relative to untreated cells. Five hundred and sixty three sequences changed by at least 2.5 fold in one or more of the 15 possible EC /cytokine combinations. The list included highly regulated adhesion molecules, chemokines, cytokines, metalloproteases, and IFN-gamma-induced genes. Overall, IFN-gamma caused the largest number of gene expression changes and its profile was least correlated with IL-4. In addition to clusters that were predominantly EC/cytokine specific, we also observed several clusters that were regulated by more than one cytokine across several ECs. Furthermore, we identified genes that were reciprocally expressed in response to different cytokines that could serve as markers of inflammatory and immune expression. These results confirm the importance of microenvironment in primary ECs that could have important applications in developing targeted therapies for vascular diseases.  相似文献   
115.
Lipopolysaccharide (LPS) signaling leading to nuclear factor-kappaB activation in mononuclear phagocytes involves interleukin-1 receptor-associated kinase (IRAK), which is rapidly activated after exposure to agonist. Although it is known that IRAK also undergoes rapid inactivation/degradation in response to LPS, providing negative feedback leading to LPS tolerance, mechanisms governing IRAK degradation are not fully understood. In the present study, examination of LPS signaling showed that IRAK degradation was bimodal and involved dual receptors and distinct pathways. Rapid degradation of IRAK, occurring within 30 min of exposure to agonist, was shown to signal through CD14/TLR4 and was regulated by phosphatidylinositol 3-kinase. A second delayed wave of IRAK degradation occurred 2 h after exposure to LPS and was mediated by CR3 independently of phosphatidylinositol 3-kinase. Thus, multiple independent mechanisms have evolved to regulate IRAK degradation, likely reflecting the importance of limiting cellular responses to LPS. Recognition of a CR3-dependent, CD14/TLR4-independent pathway leading to IRAK degradation has implications for understanding modulation of LPS responses by cells with important immunoregulatory function such as dendritic cells that are CD14(-).  相似文献   
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117.
Five grasses of tribe Aveneae were collected from low (1100 m.a.s.l.) and highland (2300 m.a.s.l.) mountain range of Western Himalaya, Neelum Valley, to evaluate the physio-anatomical adaptations to altitudinal variability. An evidence to confirm the hypothesis that plants vegetating different altitudes must be different structurally (internal modifications) and functionally due to heterogeneity in environmental gradients. The general response of all grasses to high altitude was growth retardation in terms of total leaf area per plant and dry matter. With exception of Ca2+ content, most of the ionic and chlorophyll content were significantly low at high elevations. Anatomical alterations such as, leaf thickness, intensive sclerification around the vascular bundle and pith area, reduced metaxylem vessel area, high pubescence (increased microhair and trichome density) played an important role in high degree of tolerance of these grasses to cope with altitudinal stresses. The mechanical strength of leaf, which is critical for preventing damage under harsh climate and overall survival of high altitudinal populations, seems to be depended on intensity of sclerification and dense pubescence at abaxial and adaxial surfaces of the leaf. Increase in overall thickness of leaf in high altitude grasses in response to low temperature may protect metabolically active tissue like mesophyll. Also high density of trichomes may be involved in blocking transpiration water and internal heat. Differential response of low and high altitude grasses is highly related to air temperature, pattern of rainfall, and availability of nutrients.  相似文献   
118.
119.
The efficacy of microsclerotia of Metarhizium brunneum (Petch) (Hypocreales: Clavicipitaceae) strain F52 (ARSEF 7711) was tested using samples which had been exposed on forest trees, allowing time for conidia to be produced. An aqueous slurry of microsclerotial granules (61.3% of dry mass), a straw mulch hydroseeding product (29.4%), xanthan gum as a tackifier (5.4%), and water-absorbing hydrogel (3.9%), was sprayed on small wood-veneer samples attached to tree trunks within the Ohio USDA quarantine zone for eradication of Asian longhorned beetles, Anoplophora glabripennis (Motschulsky) (Coleoptera: Cerambycidae). Samples were collected biweekly June to August, and adult female beetles in a quarantine laboratory were exposed for 2 days to individual samples after each collection. Median survival time (ST50) after exposure to samples which had been outdoors four weeks was 9.5 days (95% CI 8.5–10.5); the beetles died faster than with samples from 2 or 6–10 weeks, but slower than using positive control microsclerotial samples (ST50 6.5 days). Conidial density of field-collected samples peaked at 4 weeks, while the sprayed material gradually weathered to 33% of initial dry mass by 10 weeks. A separate field experiment in New York State compared three formulations: the hydrogel–hydromulch mixture, straw hydromulch without hydrogel, or hydrogel alone. Results were highly weather-dependent, but median beetle survival in the August bioassays was between 8.5–9.5 days for all three formulations. Overall, the hydrogel addition did not significantly improve efficacy, either during dry or rainy periods, and hydrogel alone (without hydromulch) appeared to be an additional viable option.  相似文献   
120.
AimsThe protein kinase C (PKC) family of enzymes has been implicated in cellular proliferation, differentiation, and apoptosis. However, the distribution of specific PKC isoforms with varying functions in normal and malignant human tissues remains to be determined. The objective of this study was to investigate the expression of certain PKC isoforms (α, βI, βII, ε) in human breast cancer specimens relative to adjacent uninvolved tissue (n = 24) and in the normal breast tissue obtained from patients undergoing reduction mammoplasty (n = 12).Main methodsWestern blot analysis using PKC isoform specific antibodies was performed on tissue extracts from breast tumors, adjacent uninvolved tissues, and reduction mammoplasty tissues.Key findingsMean levels of cytosolic and membrane PKC-α, PKC-βI, and PKC-βII were significantly higher in the cancer specimens than in the adjacent uninvolved breast tissues (Wilcoxon signed-ranks test; P < 0.05 for each, after adjustment for multiple comparisons). There was a notably higher mean level of membrane PKC-βII isozyme in Her-2 positive and in poorly differentiated tumors. No significant differences were observed when normal tissue adjacent to tumor was compared to breast tissue obtained from reduction mammoplasty specimens.SignificanceHigher level of PKC-α, PKC-βI, and PKC-βII in cancer specimens and higher level of PKC-βII in Her-2 positive tumors require further exploration of the intracellular pathways involving PKC-α and -β isoforms in breast cancer because both could be specific targets for the development of new therapies and for the prevention and treatment of this disease.  相似文献   
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