排序方式: 共有117条查询结果,搜索用时 31 毫秒
71.
Yaras N Bilginoglu A Vassort G Turan B 《American journal of physiology. Heart and circulatory physiology》2007,292(2):H912-H920
Stimulation of local renin-angiotensin system and increased levels of oxidants characterize the diabetic heart. Downregulation of ANG II type 1 receptors (AT(1)) and enhancement in PKC activity in the heart point out the role of AT(1) blockers in diabetes. The purpose of this study was to evaluate a potential role of an AT(1) blocker, candesartan, on abnormal Ca(2+) release mechanisms and its relationship with PKC in the cardiomyocytes from streptozotocin-induced diabetic rats. Cardiomyocytes were isolated enzymatically and then incubated with either candesartan or a nonspecific PKC inhibitor bisindolylmaleimide I (BIM) for 6-8 h at 37 degrees C. Both candesartan and BIM applied on diabetic cardiomyocytes significantly restored the altered kinetic parameters of Ca(2+) transients, as well as depressed Ca(2+) loading of sarcoplasmic reticulum, basal Ca(2+) level, and spatiotemporal properties of the Ca(2+) sparks. In addition, candesartan and BIM significantly antagonized the hyperphosphorylation of cardiac ryanodine receptor (RyR2) and restored the depleted protein levels of both RyR2 and FK506 binding protein 12.6 (FKBP12.6). Furthermore, candesartan and BIM also reduced the increased PKC levels and oxidized protein thiol level in membrane fraction of diabetic rat cardiomyocytes. Taken together, these data demonstrate that AT(1) receptor blockade protects cardiomyocytes from development of cellular alterations typically associated with Ca(2+) release mechanisms in diabetes mellitus. Prevention of these alterations by candesartan may present a useful pharmacological strategy for the treatment of diabetic cardiomyopathy. 相似文献
72.
Ahmet Yilmaz Coban Ahmet Ugur Akbal Meltem Uzun Belma Durupinar 《Memórias do Instituto Oswaldo Cruz》2015,110(5):649-654
The purpose of this study is to evaluate four rapid colourimetric methods, including
the resazurin microtitre assay (REMA), malachite green decolourisation assay (MGDA),
microplate nitrate reductase assay (MNRA) and crystal violet decolourisation assay
(CVDA), for the rapid detection of multidrug-resistant (MDR) tuberculosis.
Fifty Mycobacterium tuberculosis isolates were used in this
study. Eighteen isolates were MDR, two isolates were only resistant to isoniazid
(INH) and the remaining isolates were susceptible to both INH and rifampicin (RIF).
INH and RIF were tested in 0.25 µg/mL and 0.5 µg/mL, respectively. The agar
proportion method was used as a reference method. MNRA and REMA were performed with
some modifications. MGDA and CVDA were performed as defined in the literature. The
agreements of the MNRA for INH and RIF were 96% and 94%, respectively, while the
agreement of the other assays for INH and RIF were 98%. In this study, while the
specificities of the REMA, MGDA and CVDA were 100%, the specificity of the MNRA was
lower than the others (93.3% for INH and 90.9% for RIF). In addition, while the
sensitivity of the MNRA was 100%, the sensitivities of the others were lower than
that of the MNRA (from 94.1-95%). The results were reported on the seventh-10th day
of the incubation. All methods are reliable, easy to perform, inexpensive and easy to
evaluate and do not require special equipment. 相似文献
73.
74.
75.
76.
77.
78.
Hilal Gokturk N. Nuray Ulusu Muslum Gok Erkan Tuncay Belgin Can Belma Turan 《Molecular and cellular biochemistry》2014,387(1-2):177-186
Mutations in Ras isoforms such as K-Ras, N-Ras, and H-Ras contribute to roughly 85, 15, and 1 % of human cancers, respectively. Proper membrane targeting of these Ras isoforms, a prerequisite for Ras activity, requires farnesylation or geranylgeranylation at the C-terminal CAAX box. We devised an in vivo screening strategy based on monitoring Ras activation and phenotypic physiological outputs for assaying synthetic Ras function inhibitors (RFI). Ras activity was visualized by the translocation of RBD Raf1 -GFP to activated Ras at the plasma membrane. By using this strategy, we screened one synthetic farnesyl substrate analog (AGOH) along with nine putative inhibitors and found that only m-CN-AGOH inhibited Ras activation. Phenotypic analysis of starving cells could be used to monitor polarization, motility, and the inability of these treated cells to aggregate properly during fruiting body formation. Incorporation of AGOH and m-CN-AGOH to cellular proteins was detected by western blot. These screening assays can be incorporated into a high throughput screening format using Dictyostelium discoideum and automated microscopy to determine effective RFIs. These RFI candidates can then be further tested in mammalian systems. 相似文献
79.
80.
Forty-seven samples of corn were collected from various street bazaars and market outlets in different regions of Turkey and
total aflatoxin (AF) and ochratoxin A (OTA) levels were determined by enzyme-linked immunosorbent assay (ELISA) following
sample preparation. Levels of AF and OTA in corn samples ranged between 1.75–120.3 μg/kg and 1.08–8.57 μg/kg, respectively.
Although 53% of the samples analysed had no detectable levels of AF, 4% of similar samples were found to contain AFs above
the acceptable limit of 10 μg/kg in Turkey. For OTA, 4% of the corn samples had levels above the acceptable limit (3 μg/kg)
in Turkey, with over 43% samples not found to contain this mycotoxin. Although the levels of mycotoxins analysed in this study
were not found to be high and the percentage of samples contaminated above permitted limits were low, the importance of overall
daily dietary intake should not be underestimated and control of these fungal metabolites in corn must be explored to minimise
the hazards they may cause in humans. 相似文献