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221.
Biological activities of a series of palladium(II) complexes (M1–M9) bearing NN, NS, and NO chelating ligands are reported. The palladium complexes were tested for their cytotoxic properties against human cervical cancer (HeLa) cells and antibacterial activity against Gm+ve and Gm–ve bacteria. Among the palladium complexes studied (M1-M9), the complex M5, M8, and M9 were found to be more effective in inhibiting the proliferation of HeLa cells. Hence, these complexes were further investigated for their potential role in cellular damage and apoptosis. DCFDA staining, Rhodamine 123 staining and DNA cleavage assay revealed that complex M5, M8 and M9 induced apoptotic cell death in HeLa cells through ROS generation, DNA damage and mitochondrial depolarization. Computational and titration studies also indicated strong electrostatic interaction with DNA groove. Most of the complexes exhibited good antibacterial activity against both Gm+ve and Gm−ve bacteria. The antibacterial activity of the compounds could not be correlated with their anticancer activity indicating a differential mechanism at their effective concentrations. The detailed study on the antibacterial mechanism of the most potent complex M7 revealed that it exerted its antibacterial activity by inhibiting the function of FtsZ and perturbing the localization of the Z-ring at the mid cell.  相似文献   
222.
High Mobility Group AT‐hook 1 (HMGA1) was identified as a target of miR‐214 in human cervical and colorectal cancers (CaCx and CRC) in a previous study. While the expression of miR‐214 remains suppressed, HMGA1 behaves as a potent oncogene and plays crucial roles in several aberrant signalling pathways by interacting with intermediates like RELA, CTNNB1, STAT3, and TP53 in CaCx and CRC. Hypothetically, miR‐214 should be able to regulate the stabilization of some of these intermediates through the regulation of HMGA1. This was assessed by ectopically expressing miR‐214 or complementarily, by inhibiting the expression of HMGA1. In promoter luciferase assays, miR‐214 inhibited NF‐κB and Wnt activities but elevated TP53 activity in cancer cells. Further, miR‐214 suppressed the expression of HMGA1, RELA, CTNNB1, and STAT3 while elevating TP53 levels, similar to when small interfering RNA (siRNA) against HMGA1 was used, as revealed by Western blotting. It is suggested that poor expression of miR‐214, commonly reported in CaCx and CRC tissues, may not only result in the sustained expression of HMGA1 but also that of RELA, CTNNB1, and STAT3, and a congruent suppression of TP53 during cancer initiation/progression. These several states are, however, reversed when miR‐214 is reintroduced and could explain the tumour suppressive functions observed in earlier studies. Further studies are, however, required to reveal how microRNA‐mediated regulation of HMGA1 expression may affect individual signalling pathways in CaCx and CRC. Current results reveal that miR‐214 is not only able to regulate the expression of its direct target, HMGA1, but also that of a few signalling intermediates like TP53, RELA, CTNNB1, and STAT3, with which HMGA1 interacts. These intermediates play crucial roles in signalling pathways commonly deregulated in human CaCx and CRC. Hence, it is proposed that miR‐214 might act as a tumour suppressor by regulating several aberrant signalling pathways through HMGA1. This knowledge has the potential to help design novel therapeutic strategies in CaCx and CRC.  相似文献   
223.
Drug-induced action potential (AP) prolongation leading to Torsade de Pointes is a major concern for the development of anti-arrhythmic drugs. Nevertheless the development of improved anti-arrhythmic agents, some of which may block different channels, remains an important opportunity. Partial block of the late sodium current (INaL) has emerged as a novel anti-arrhythmic mechanism. It can be effective in the settings of free radical challenge or hypoxia. In addition, this approach can attenuate pro-arrhythmic effects of blocking the rapid delayed rectifying K+ current (IKr). The main goal of our computational work was to develop an in-silico tool for preclinical anti-arrhythmic drug safety assessment, by illustrating the impact of IKr/INaL ratio of steady-state block of drug candidates on “torsadogenic” biomarkers. The O’Hara et al. AP model for human ventricular myocytes was used. Biomarkers for arrhythmic risk, i.e., AP duration, triangulation, reverse rate-dependence, transmural dispersion of repolarization and electrocardiogram QT intervals, were calculated using single myocyte and one-dimensional strand simulations. Predetermined amounts of block of INaL and IKr were evaluated. “Safety plots” were developed to illustrate the value of the specific biomarker for selected combinations of IC50s for IKr and INaL of potential drugs. The reference biomarkers at baseline changed depending on the “drug” specificity for these two ion channel targets. Ranolazine and GS967 (a novel potent inhibitor of INaL) yielded a biomarker data set that is considered safe by standard regulatory criteria. This novel in-silico approach is useful for evaluating pro-arrhythmic potential of drugs and drug candidates in the human ventricle.  相似文献   
224.
A high-performance thin-layer chromatographic (HPTLC) method for quantitation of ibuprofen from plasma is described. The drug was extracted from acidified plasma with hexane-isopropanol (85:15). The mobile phase composition was n-hexane-ethyl acetate-anhydrous acetic acid (75:25:2). Densitometric analysis of ibuprofen was carried out at 222 nm. The calibration curves of ibuprofen in chloroform and in plasma were linear over the range 2–20 μg. The mean values of intercept, slope and correlation coefficient were 0.0422±0.0018, 0.0356±0.0213 and 0.9976±0.0013 for standard curves in chloroform and 0.1044±0.003, 0.8759±0.0213 and 0.9939±0.001 for standard curves in plasma, respectively. The limit of detection of ibuprofen from human plasma (assay sensitivity) was 50 ng and no interference was found from endogenous compounds. The recovery of ibuprofen from human plasma using the described extraction procedure was about 85%. The mean relative standard deviations for within-day and between-day analyses were 2.24 and 2.6% for 5 μg and 3.67 and 3.2% for 15μg ibuprofen concentration, respectively. The method was utilized to monitor the plasma concentration of ibuprofen post administration of sustained release capsules in human patient volunteers.  相似文献   
225.
226.
The emerging viral diseases haemorrhagic fever with renal syndrome (HFRS) and hantavirus cardiopulmonary syndrome (HCPS) are a cause of global concern as they are increasingly reported from newer regions of the world. The hantavirus species causing HFRS include Hantaan virus, Seoul virus, Puumala virus, and Dobrava-Belgrade virus while Sin Nombre virus was responsible for the 1993 outbreak of HCPS in the Four Corners Region of the US. Humans are accidental hosts and get infected by aerosols generated from contaminated urine, feces and saliva of infected rodents. Rodents are the natural hosts of these viruses and develop persistent infection. Human to human infections are rare and the evolution of the virus depends largely on that of the rodent host. The first hantavirus isolate to be cultured, Thottapalayam virus, is the only indigenous isolate from India, isolated from an insectivore in 1964 in Vellore, South India. Research on hantaviruses in India has been slow but steady since 2005. Serological investigation of patients with pyrexic illness revealed presence of anti-hantavirus IgM antibodies in 14.7% of them. The seropositivity of hantavirus infections in the general population is about 4% and people who live and work in close proximity with rodents have a greater risk of acquiring hantavirus infections. Molecular and serological evidence of hantavirus infections in rodents and man has also been documented in this country. The present review on hantaviruses is to increase awareness of these emerging pathogens and the threats they pose to the public health system.  相似文献   
227.
Genetica - Understanding the molecular associations underlying pathogen resistance in invasive plant species is likely to provide useful insights into the effective control of alien plants, thereby...  相似文献   
228.
Sridharan  R.  Domnic  S. 《Cluster computing》2021,24(2):1381-1396
Cluster Computing - Using cloud computing as a base, new technologies like data analytics, Internet of Things, machine learning etc., have emerged. Applications that use these technologies, depend...  相似文献   
229.
To assess the current situation regarding the incidence of red rust disease in tea plants, an extensive survey was conducted in southern Indian tea plantations covering different tea cultivars and agroclimatic zones. The results indicated that the incidence of disease was more severe in tea seedlings than clones in all the agroclimatic zones. On the other hand, a simple, reliable, and reproducible technique was standardized for culturing Cephaleuros parasiticus G. Karst. isolated from infected tea leaves. Ten isolates were obtained, of which two were screened based on growth rate and culture characters for further studies. Ten culture media were tested for the culturing of C. parasiticus in which Trebouxia and Bristol media were the best followed by George, Go algal, and tea leaf extract media. Variations between isolates (Valparai C. parasiticus field number 27 [VCP27], Munnar C. parasiticus field number 11 [MCP11], and University of Texas culture number 2412 [UTEX2412]) of C. parasiticus were studied based on the growth pattern, protein expression profile, and cellular constituents in the filaments. The quantitative estimation of cellular constituents showed that there was no significant difference in these constituents among isolates. The detection of amino acids in the filaments of C. parasiticus isolates showed 16 free forms and 11 bound forms. Amino acids in bound form were higher in all the isolates than in free form of amino acids. The three isolates of C. parasiticus were closely related, with bands lying between the molecular weight of 116 and 35 kDa.  相似文献   
230.
The present study was undertaken to investigate the protective effect of Indian honey on acetaminophen induced oxidative stress and liver damage in rat. Honey serves as a source of natural medicine, which is effective to reducing the risk of heart disease, liver toxicity and inflammatory processes. The hepatoprotective activity of the Indian honey was determined by assessing levels of Serum transaminases, ALP and total bilirubin. Finally, the effects of the test substances on the antioxidant enzymes of the liver were also studied by assessing changes in the level of reduced glutathione, glutathione peroxidase, catalase and superoxide dismutase. Serum transaminase, ALP and total bilirubin level were significantly elevated and the antioxidant status in liver such as activities of SOD, CAT, GPx and the levels of GSH were declined significantly in APAP alone treated animals. Pretreatment with honey and silymarin prior to the administration of APAP significantly prevented the increase in the serum levels of hepatic enzyme markers and reduced oxidative stress. The histopathological evaluation of the livers also revealed that honey reduced the incidence of liver lesions induced by APAP. Results suggest that the Indian honey protects liver against oxidative damage and it could be used as an effective hepatoprotector against APAP induced liver damage.  相似文献   
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