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991.
Seven new platinum(II) complexes (1–7) of triethylphosphine (Et3P) and thiones (L) with general formula, cis-[Pt(Et3P)2(L)2]Cl2 were prepared and characterized by elemental analysis, FTIR and NMR (1H, 13C & 31P) measurements. The analytical and spectroscopic data suggested the formation of the desired complexes. The complexes were tested for in vitro cytotoxicity against four cell lines: Hela (human cervical adenocarcinoma), MCF-7 (human breast carcinoma), A549 (human lung carcinoma), and HTC15 (human colon carcinoma). The anticancer activity values of compounds 1–6 are much better than cisplatin and carboplatin as indicated by their IC50 values.  相似文献   
992.
The diversity, ecology, and seasonality for sand flies from two localities in Jenin District, the Palestinian Territories, were studied. A total of 12,579 sand flies (5,420 Phlebotomus and 7,159 Sergentomyia) were collected during the study period. The genera Phlebotomus and Sergentomyia are represented by 13 and nine species and subspecies, respectively. Species account was given for all collected species. CDC light traps yielded 7,649 (60.8%) of the total captured sand flies, while sticky traps and aspirators contributed to 36.4 and 2.8% of the total collected specimens, respectively. Phlebotomus sergenti and P. syriacus showed two peaks, one in July and one in October. Phlebotomus tobbi showed one peak towards the end of the summer in September and August, while P. papatasi showed a bimodal peaks pattern, one in June and one in October. Phlebotomus canaaniticus showed a peak in August. P. perfiliewi transcaucasicus and P. neglectus showed a peak in October. Sergentomyia dentata showed one peak in August and increasing numbers from June to August, declining afterwards. Other species, such as S. theodori, had one peak in June, S. taizi had steady numbers across the summer, and S. christophersi had a peak in August.  相似文献   
993.
Circulating microRNAs (miRNAs) have been shown as promising biomarkers for various diseases. We investigated the predictive potential of circulating endothelium-enriched miR-126 in type 2 diabetes patients (T2D) without chronic complications and T2D patients with coronary artery diseases (CAD). The expression levels of circulating miR-126, determined by quantitative real time PCR, were decrease in peripheral blood of T2D patients and T2D with CAD compared with healthy controls. MiR-126 strongly associated with T2D and CAD, negatively correlated with LDL in CAD patients and differentiated between T2D patients, T2D patients with CAD and healthy subjects. Circulating miR-126 may serve as a biomarker for predicting patients with T2D and diabetic CAD.  相似文献   
994.
The noctuid stalk borers, Sesamia spp. (S. cretica Led. and S. nonagrioides Lef.), damage a considerable percentage of sugarcane internodes annually in the province of Khuzestan, Iran. A study was conducted to quantify the relationship between stalk borer damage and sugar quality to estimate the monetary loss incurred at these levels of damage at harvest time. Three commercial varieties of sugarcane (SP70‐1143, CP69‐1062 and CP48‐103) were studied to determine the effects of damage on sugar quality. Stalks were separated into seven groups: control (without damage); one to five bored internodes per stalk; and more than five bored internodes per stalk. The percentage of bored internodes and several parameters, such as pol and brix, were measured. Sugar in the control group was 123.78, 123.72 and 104.84 kg/ton for SP70‐1143, CP69‐1062 and CP48‐103, respectively. Sugar per ton, juice purity, pol and brix were all significantly inversely correlated to the percentage of bored internodes. Estimated sugar losses for every 1% bored internode were 0.17, 0.39 and 0.23% (equal to 210, 482 and 241 kg sugar) in SP70‐1143, CP69‐1062 and CP48–103, respectively. These varieties could tolerate damage of up to 18.1, 11.7 and 18.9% bored internodes, respectively, compared to the control. Regression slopes for CP69‐1062 were slightly higher than those of the other two varieties. Therefore, based on quality damage, CP69‐1062 is susceptible to stalk borer damage.  相似文献   
995.
Inflammatory bowel disease (IBD) is a chronic recurrent disease of the digestive tract with an unknown etiology. The aim of this study was to examine the possible protective effects of N-acetylcysteine (NAC) in the mouse model of IBD by measuring specific biomarkers in the colon cells. Colitis was induced by administration of dextran sodium sulfate (DSS) in drinking water (3%) for 7 days. Three doses of NAC (106, 160, and 240 mg/kg) were given after induction of colitis (4 days post DSS) for 4 days by gavage. Lipid peroxides (LP), total antioxidant power (TAP), total thiol molecules (TTM), tumor necrosis factor-α (TNF-α), nitric oxide (NO), superoxide dismutase (SOD), and catalase (CAT) were measured in the colon homogenate of the treated animals. NAC (160 and 240 mg/kg) significantly decreased LP, TNF-α, NO and increased TTM, SOD, and CAT. The TAP was also increased by NAC (240 mg/kg). It is concluded that moderate to high doses of NAC improves cellular biomarkers of IBD in mice. Further studies should be trialled in humans suffering from two common inflammatory bowel disease called ulcerative colitis and Crohn’s disease.  相似文献   
996.
Khoja S  Ojwang P  Khan S  Okinda N  Harania R  Ali S 《PloS one》2008,3(9):e3191

Background

Genetic analysis of a viral infection helps in following its spread in a given population, in tracking the routes of infection and, where applicable, in vaccine design. Additionally, sequence analysis of the viral genome provides information about patterns of genetic divergence that may have occurred during viral evolution.

Objective

In this study we have analyzed the subtypes of Human Immunodeficiency Virus -1 (HIV-1) circulating in a diverse sample population of Nairobi, Kenya.

Methodology

69 blood samples were collected from a diverse subject population attending the Aga Khan University Hospital in Nairobi, Kenya. Total DNA was extracted from peripheral blood mononuclear cells (PBMCs), and used in a Polymerase Chain Reaction (PCR) to amplify the HIV gag gene. The PCR amplimers were partially sequenced, and alignment and phylogenetic analysis of these sequences was performed using the Los Alamos HIV Database.

Results

Blood samples from 69 HIV-1 infected subjects from varying ethnic backgrounds were analyzed. Sequence alignment and phylogenetic analysis showed 39 isolates to be subtype A, 13 subtype D, 7 subtype C, 3 subtype AD and CRF01_AE, 2 subtype G and 1 subtype AC and 1 AG. Deeper phylogenetic analysis revealed HIV subtype A sequences to be highly divergent as compared to subtypes D and C.

Conclusion

Our analysis indicates that HIV-1 subtypes in the Nairobi province of Kenya are dominated by a genetically diverse clade A. Additionally, the prevalence of highly divergent, complex subtypes, intersubtypes, and the recombinant forms indicates viral mixing in Kenyan population, possibly as a result of dual infections.  相似文献   
997.
Mitochondrial dysfunction including that caused by oxidative stress has been implicated in the pathogenesis of neurodegenerative diseases. Glutaredoxin 1 (Grx1), a cytosolic thiol disulfide oxido-reductase, reduces glutathionylated proteins to protein thiols and helps maintain redox status of proteins during oxidative stress. Grx1 downregulation aggravates mitochondrial dysfunction in animal models of neurodegenerative diseases, such as Parkinson's and motor neuron disease. We examined the mechanism underlying the regulation of mitochondrial function by Grx1. Downregulation of Grx1 by shRNA results in loss of mitochondrial membrane potential (MMP), which is prevented by the thiol antioxidant, alpha-lipoic acid, or by cyclosporine A, an inhibitor of mitochondrial permeability transition. The thiol groups of voltage dependent anion channel (VDAC), an outer membrane protein in mitochondria but not adenosine nucleotide translocase (ANT), an inner membrane protein, are oxidized when Grx1 is downregulated. We then examined the effect of beta-N-oxalyl amino-L-alanine (L-BOAA), an excitatory amino acid implicated in neurolathyrism (a type of motor neuron disease), that causes mitochondrial dysfunction. Exposure of cells to L-BOAA resulted in loss of MMP, which was prevented by overexpression of Grx1. Grx1 expression is regulated by estrogen in the CNS and treatment of SH-SY5Y cells with estrogen upregulated Grx1 and protected from L-BOAA mediated MMP loss. Our studies demonstrate that Grx1, a cytosolic oxido-reductase, helps maintain mitochondrial integrity and prevents MMP loss caused by oxidative insult. Further, downregulation of Grx1 leads to mitochondrial dysfunction through oxidative modification of the outer membrane protein, VDAC, providing support for the critical role of Grx1 in maintenance of MMP.  相似文献   
998.

Background  

Salmonella enterica serotype Enteritidis (S. Enteritidis) is a zoonotic pathogen, which can be found in many sources including animals and the environment. However, little is known about the molecular relatedness among S. Enteritidis isolates from different sources. We have applied multiple-locus variable number tandem repeat analysis (MLVA) to study the genetic diversity of S. Enteritidis isolates from human and non-human sources.  相似文献   
999.
During the antigen-dependant activation process several subsets CD8+ T cells appear with different phenotypic and functional characteristics. Recent studies indicate that the state of T cell differentiation radically affects their ability to effectively respond to tumor challenge, with early effector CD8+ T (CD62Lhigh) cells having better anti-tumor activity. Thus strategies aimed at optimizing the generation of such subpopulations could significantly enhance the effectiveness of adoptive cell therapy (ACT) for cancer. In this study, we show that priming of naïve CD8+ T cells in the presence of IL-12 selectively rescued early CD8+ CD62Lhi from activation induced cell death and resulted in the increased accumulation of this subset of CD8+ T cells. Furthermore, we demonstrated that IL-12 directly modulated the expression of CD62L on activated CD8+ T cells. When used for ACT, naïve CD8+ T cells primed in vitro in the presence of IL-12 showed superior anti-tumor activity toward B16 melanoma. Importantly, using the Pmel-1 model, priming pmel-1 cells in vitro with IL-12 reduced the state of functional tolerance associated with the non-mutated “self” tumor antigen gp100, as demonstrated by significant tumor responses in the absence of vaccination. Together, our results suggest that in vitro conditioning of naïve CD8+ T cells with IL-12 prior to ACT could significantly enhance their anti-tumor activity.  相似文献   
1000.
This study was aimed at determination of pharmacokinetic parameters of copper (II) acetylsalicylate (CAS). Ten volunteers received a 60-mg dose of CAS. Blood samples were collected just before and after 0.25, 0.5, 0.75, 1.0, 1.5, 2.5, 3.0, 3.5, 4.0, 4.5, 5.5, 7.0, 10, and 12.0 h of administration of the drug. The plasma samples were analyzed for CAS and its metabolites by a validated high-performance liquid chromatography method having a suitable lower limit of quantification. The dose of 60 mg was well tolerated without any adverse effect. The maximum plasma concentration of CAS was found to be 0.38 mg L(-1) with t (max) of 0.72 h. The plasma half-life, clearance, and volume of distribution of CAS were 8.67 h, 66.30 L h(-1) and 829 L kg(-1), respectively. The elimination of CAS, acetylsalicylic acid, copper salicylate, and salicylic acid follows the first order kinetics with r (2) 0.979, 0.880, 0.991, and 0.998, respectively. The study provided for the first time the pharmacokinetic data for CAS after oral administration of CAS. The data were found to be useful in understanding the claimed enhanced anti-inflammatory activity of the drug as compared with that of acetylsalicylic acid.  相似文献   
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