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31.
ABSTRACTThe present study investigates the circadian behavior of spontaneously hypertensive rats (SHRs) during the pre-hypertensive and hypertensive stage, with the aim to gain insight into whether observed changes in the functionality of suprachiasmatic nucleus (SCN) in the hypertensive state are cause or consequence of hypertension. Four types of animals were used in this study: (1) SHRs which develop hypertension genetically; (2) their normotensive controls, Wistar Kyoto rats (WKYs); (3) Wistar rats whereby hypertension was surgically induced (2 Kidney 1 Clamp (2K1C) method); and (4) sham-operated control Wistar rats. Period length and activity levels and amplitude changes of locomotor and wheel running activity were determined, in constant conditions, as a measure of the functionality of the SCN. Hereto two conditions were used, constant darkness (0 lux) and constant dim (5 lux) light. SHRs showed a shortened period of their locomotor and running wheel activity rhythms in constant darkness during both pre-hypertensive and hypertensive stages and exhibited period lengthening in constant dim light conditions, only during hypertensive stages. Total amount as well as the amplitude of daily running wheel rhythms showed an inverse correlation with the period length, and this relation was significantly different in SHRs compared to WKYs. None of the aforementioned changes in circadian rhythms were observed after the surgical induction of hypertension. The present findings suggest early functional changes of the SCN in the etiology of spontaneous hypertension. 相似文献
32.
This article is a historical empirical study of the Albanian Muslim migrant community of Shepparton. Through analysing newspaper reports, the authors discuss how these migrants were portrayed as liminal between their first arrival and acceptance as Australians a generation later. This is characteristic of a practice which the authors term “migrant hazing”, where a migrant group is demonized as a threat to the society during the liminal phase. Migrant hazing occurs in public discourse, particularly the media, and ceases with the replacement of the group by newer migrants, who are subjected to the same process. Furthermore, migrant hazing remains present in contemporary depictions of Australian Muslims. In this longitudinal study, media reports on Albanian Muslims revolved around three persistent themes: their supposed criminality, the wrongful use of land and the threat of dual-loyalty. These three items constituted the main weapons of the media in hazing the first, liminal generation. 相似文献
33.
Cihan Gokce Huseyin Yilmaz Zeynep Erbas Zihni Demirbag Ismail Demir 《Journal of nematology》2013,45(4):253-259
During a survey of entomopathogenic nematodes (EPNs) in the eastern Black Sea region of Turkey in 2009–2012, a steinernematid species was recorded and isolated using the Galleria-baiting method. The isolate was identified as Steinernema kraussei based on its morphological and molecular properties. The analysis of the ITS rDNA sequence placed the Turkish population of S. kraussei in the “feltiae-kraussei” group in the clade that contains different isolates of the species. This is the first record of S. kraussei from Turkey. The efficacy of S. kraussei was tested on Agrotis segetum (Lepidoptera: Noctuidea) larvae at different densities (100, 300, and 500 infective juveniles (IJs) g−1 dry sand ) in laboratory conditions at 25 °C. The highest mortality (98%) was obtained with 500 IJs g−1 dry sand within 7 d after inoculation. Our results indicate that the new isolate is a highly promising biological control agent against A. segetum, one of the most serious soil pests of agricultural area and fruits worldwide. 相似文献
34.
Madhura S. Mehta Sonia C. Dolfi Roman Bronfenbrener Erhan Bilal Chunxia Chen Dirk Moore Yong Lin Hussein Rahim Seena Aisner Romona D. Kersellius Jessica Teh Suzie Chen Deborah L. Toppmeyer Dan J. Medina Shridar Ganesan Alexei Vazquez Kim M. Hirshfield 《PloS one》2013,8(7)
Several epidemiological studies have suggested a link between melanoma and breast cancer. Metabotropic glutamate receptor 1 (GRM1), which is involved in many cellular processes including proliferation and differentiation, has been implicated in melanomagenesis, with ectopic expression of GRM1 causing malignant transformation of melanocytes. This study was undertaken to evaluate GRM1 expression and polymorphic variants in GRM1 for associations with breast cancer phenotypes. Three single nucleotide polymorphisms (SNPs) in GRM1 were evaluated for associations with breast cancer clinicopathologic variables. GRM1 expression was evaluated in human normal and cancerous breast tissue and for in vitro response to hormonal manipulation. Genotyping was performed on genomic DNA from over 1,000 breast cancer patients. Rs6923492 and rs362962 genotypes associated with age at diagnosis that was highly dependent upon the breast cancer molecular phenotype. The rs362962 TT genotype also associated with risk of estrogen receptor or progesterone receptor positive breast cancer. In vitro analysis showed increased GRM1 expression in breast cancer cells treated with estrogen or the combination of estrogen and progesterone, but reduced GRM1 expression with tamoxifen treatment. Evaluation of GRM1 expression in human breast tumor specimens demonstrated significant correlations between GRM1 staining with tissue type and molecular features. Furthermore, analysis of gene expression data from primary breast tumors showed that high GRM1 expression correlated with a shorter distant metastasis-free survival as compared to low GRM1 expression in tamoxifen-treated patients. Additionally, induced knockdown of GRM1 in an estrogen receptor positive breast cancer cell line correlated with reduced cell proliferation. Taken together, these findings suggest a functional role for GRM1 in breast cancer. 相似文献
35.
I. O Yuksel G. Cagirci E. Koklu A. Yilmaz S. Kucukseymen H. Y. Ellidag S. Cay N. Yilmaz S. Arslan 《Netherlands heart journal》2016,24(10):609-616
Objective
Erythropoietin (EPO) improves cardiac function and induces neovascularisation in post-myocardial infarction heart failure. The aim of this study was to analyse the association between the serum erythropoietin level and coronary collateral development in patients with coronary artery disease and chronic total occlusion.Methods
A total of 168 patients consisting of 117 with coronary artery disease (CAD, (62 with chronic total occlusion (CTO), 55 without CTO)) and 51 with healthy coronary arteries were included in the study. The patients were assigned as coronary artery disease without CTO (group 0), CAD with CTO (group 1: poor collateral development, group 2: good collateral development) and normal coronary arteries (group 3).Results
There was a significant positive correlation between serum EPO levels and the Rentrop scores in angiography (r = 0.243, p = 0.001). Similarly, a positive correlation was found between serum EPO levels and the Syntax scores (r = 0.253, p = 0.001). Echocardiography revealed a negative correlation between serum EPO levels and the cardiac ejection fraction (r = ?0.210, p = 0.006).Conclusions
Serum EPO is a useful biomarker for coronary collateral development in patients with CTO.36.
37.
Iqbal Tahir Ijaz Mohsin Javaid Muhammad Rafique Muhammad Riaz Khalid Nadeem Tahir Muhammad Bilal Nabi Ghulam Abrar Muhammad Afsheen Sumera 《Plasmonics (Norwell, Mass.)》2019,14(1):147-154
Plasmonics - Effect of different gold (Au) grating structures on light absorption in solar cell is investigated by finite elemental analysis using COMSOL multiphysics-RF module. The geometry of the... 相似文献
38.
A conserved GH17 glycosyl hydrolase from plant pathogenic Dothideomycetes releases a DAMP causing cell death in tomato 总被引:1,自引:0,他引:1
To facilitate infection, pathogens deploy a plethora of effectors to suppress basal host immunity induced by exogenous microbe-associated or endogenous damage-associated molecular patterns (DAMPs). In this study, we have characterized family 17 glycosyl hydrolases of the tomato pathogen Cladosporium fulvum (CfGH17) and studied their role in infection. Heterologous expression of CfGH17-1 to 5 by potato virus X in different tomato cultivars showed that CfGH17-1 and CfGH17-5 enzymes induce cell death in Cf-0, Cf-1 and Cf-5 but not in Cf-Ecp3 tomato cultivars or tobacco. Moreover, CfGH17-1 orthologues from other phytopathogens, including Dothistroma septosporum and Mycosphaerella fijiensis, also trigger cell death in tomato. CfGH17-1 and CfGH17-5 are predicted to be β-1,3-glucanases and their enzymatic activity is required for the induction of cell death. CfGH17-1 hydrolyses laminarin, a linear 1,3-β-glucan with 1,6-β linkages. CfGH17-1 expression is down-regulated during the biotrophic phase of infection and up-regulated during the necrotrophic phase. Deletion of CfGH17-1 in C. fulvum did not reduce virulence on tomato, while constitutive expression of CfGH17-1 decreased virulence, suggesting that abundant presence of CfGH17-1 during biotrophic growth may release a DAMP that activates plant defence responses. Under natural conditions CfGH17-1 is suggested to play a role during saprophytic growth when the fungus thrives on dead host tissue, which is in line with its high levels of expression at late stages of infection when host tissues have become necrotic. We suggest that CfGH17-1 releases a DAMP from the host cell wall that is recognized by a yet unknown host plant receptor. 相似文献
39.
Muhammad Bilal Sadia Noreen Syed Zakir Hussain Shah Ram Naresh Bharagava 《Biocatalysis and Biotransformation》2019,37(3):159-182
Enzyme-based catalysis has become one of the most important disciplines in organic synthesis and plays a noteworthy role in the establishment of many chemical industries, e.g. fine chemicals, food or energy, textiles, agricultural, cosmeceutical, medicinal and pharmaceutical industries. However, pristine enzymes fail to demonstrate requisite functionalities for an industrial setting where extremely specific and stable catalysts are required. Immobilization enhances the catalytic stability and activity of enzymes and trims the overall cost burden of the enzyme. Therefore, it widely endeavours for proficient, sustainable, and environmentally responsive catalytic processes. Amongst several immobilization strategies, e.g. (1) supports-assisted, i.e. physical or covalent coupling and (2) supports-free techniques, i.e. cross-linked enzyme crystals (CLECs) or aggregates are the most promising ones and widely pursued for enzyme immobilization purposes. This perspective review focuses on up-to-date developments in the area of enzyme immobilization and presents their potentialities to upgrade and/or modify enzyme properties. Both types of immobilization strategies, i.e. supports-assisted and supports-free techniques are discussed with particular reference to CLECs or aggregates and protein-coated microcrystals. Also, several useful traits achieved after immobilization are also discussed in the second half of the review. 相似文献
40.