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301.
Güven Cetin Tuba Ozkan Seda Turgut M. Ali Cikrikcioglu M. Cem Ar Mesut Ayer Ayhan Unlu Sevda Rabia Celik Yahya Sekin Cumali Karatoprak 《Molecular biology reports》2014,41(10):6737-6742
Essential thrombocythemia (ET) is an entity of classic Philadelphia chromosome-negative myeloproliferative neoplasms (MPNs), characterized by thrombocytosis with megakaryocytic hyperplasia and thrombocytes are increased with abnormal functions. Discovery of the protein tyrosine kinase JAK2 V617F allele contributed to better understanding of the pathogenetic mechanisms of MPNs. Acquired single point mutation in the JAK2 V617F was determined approximately 50–60 % of patients with ET. In this study we aimed to investigate the relationship between JAK2 V617F gene mutation, hematologic, biochemical markers and the complications in the ET patients. A total of 268 patients diagnosed with ET and 219 of those studied for JAK2 gene mutation were followed at the hematology clinics of three major hospitals between 2008 and 2013 were screened retrospectively. Laboratory, clinical and hematologic parameters were compared for JAK2 V617F positive and JAK2 V617F negative patients with ET. 102 (46 %) patients were positive with the JAK2 V617F mutation. The complications were observed in 61 (28 %) patients and 38 (62 %) of them had JAK2 V617F mutation. The levels of white blood cells, neutrophil, basophil, red blood cells, hemoglobin, hematocrit, mean platelet volume, thrombocytes, eosinophil; urea, creatinine were significantly different in patients with the JAK2 V617F mutation (P < 0.05). Presence of the JAK2 V617F mutation supports the diagnosis of ET. It would be useful to investigate the JAK2 V617F mutation and the hematologic and biochemical markers at diagnosis with respect to consider the risk of developing complications and to take the precautions against these complications. 相似文献
302.
Effects of Echis pyramidum Snake Venom on Hepatic and Renal Antioxidant Enzymes and Lipid Peroxidation in Rats 下载免费PDF全文
Abdulrahman K. Al Asmari Haseeb A. Khan Rajamohammed A. Manthiri Khalid M. Al Yahya Kitab E. Al Otaibi 《Journal of biochemical and molecular toxicology》2014,28(9):407-412
The effects of Echis pyramidum venom (EPV) (0.25, 0.50, and 1.00 mg/kg) on activities of superoxide dismutase (SOD) and catalase (CAT) and levels of thiobarbituric acid reactive substances (TBARS) and total thiols (T‐SH) in liver and kidneys of rats were investigated. EPV significantly and dose dependently decreased the activities of SOD and CAT in livers. Although the kidney SOD and CAT activities were not affected by low and medium doses of EPV, the high dose significantly reduced the activities of these enzymes. Liver and kidney TBARS levels were not affected by the low and medium doses of EPV, whereas the high dose significantly increased the TBARS after 6 h postdosing. There was a significant depletion of T‐SH in liver and kidneys of rats exposed to a high dose of EPV. The acute phase oxidative stress due to an EPV injection points toward the importance of an early antioxidant therapy for the management of snake bites. 相似文献
303.
Mohammed Rebbah Yahya Slimani Abdelkader Benyettou Lionel Brunie 《Cluster computing》2016,19(1):13-27
Computational grids have the potential for solving large-scale scientific problems using heterogeneous and geographically distributed resources. At this scale, computer resources and network failures are no more exceptions, but belong to the normal system behavior. Therefore, one of the most valuable characteristics of grid tools, apart from the performance they can achieve, is fault tolerance, which is a significant and complex issue in grid computing systems. In this paper, we propose a fault tolerant model for grid computing systems namely DCFT. This model is based on dynamic colored graphs without replication of computer resources. The proposed faut tolerance model consists of two stages. In the first stage, each node is described by a state vector. We color each attribute of the state vector as three colors (green, blue and red) based on its level of performance. In the second stage, we classify the nodes of a grid into three categories: the identical computer resources in term of performance, the more efficient ones and the less efficient ones. We used the colors of the nodes to develop a new strategy for fault tolerance based on the level of performance. A simulation of the proposed model using SimGrid simulator and Graphstream is conducted. Experimental results show that the proposed model performs very well in a large grid environment. 相似文献
304.
Background
In microarray data analysis, factors such as data quality, biological variation, and the increasingly multi-layered nature of more complex biological systems complicates the modelling of regulatory networks that can represent and capture the interactions among genes. We believe that the use of multiple datasets derived from related biological systems leads to more robust models. Therefore, we developed a novel framework for modelling regulatory networks that involves training and evaluation on independent datasets. Our approach includes the following steps: (1) ordering the datasets based on their level of noise and informativeness; (2) selection of a Bayesian classifier with an appropriate level of complexity by evaluation of predictive performance on independent data sets; (3) comparing the different gene selections and the influence of increasing the model complexity; (4) functional analysis of the informative genes. 相似文献305.
Yeoh Seak Hui A. A. Amirul Ahmad R. M. Yahya M. N. M. Azizan 《World journal of microbiology & biotechnology》2010,26(1):79-84
Aspergillus terreus, isolated from rotting bagasse, showed comparable cellulolytic activities when grown either in the free or immobilized states
with cellulose as the sole carbon source. The cultural and nutritional requirements for maximum cellulase production by the
organism either in the free or immobilized states were similar, except an increase in the temperature optimum from 30 to 40°C,
occurred upon immobilization. In the free state, the maximum filter paper hydrolase, carboxymethylcellulase and β-glucosidase
activities produced were 2.1, 13.6, and 3.2 U/ml, respectively, while in the immobilized state, the levels were 1.8, 12.0,
and 2.4 U/ml. Production of cellulolytic enzymes by immobilized cells was influenced by the surface area of the support material.
In addition, cells in the immobilized state sustained enzyme production for a much longer period with a 4.5-fold increase
in productivity during repeated batch when compared to free cells. 相似文献
306.
307.
Some alpha,omega-alkanediyl bis-dimethylammonium bromide compounds (gemini surfactants) referred as "m-s-m" have been synthesized, purified and characterized by usual spectroscopic methods. These compounds have been screened for antibacterial activity against Escherichia coli, Pseudomonas aeruginosa and Staphylococcus aureus. Their activity was compared. The compounds tested showed excellent in vitro antibacterial activity against Staphylococcus aureus ranging from 1.5 to 20 microg/ml and had variable activity against E. coli with minimum minimum inhibitory concentration (MIC) of 50 microg/ml. These compounds are less active against P. aeruginosa. On the other hand, contrary to the antibacterial activity of these products against S. aureus, a relation between the MIC and the critical micellar concentration (CMC) was found and relationship between chain's Length and antibacterial activity was found. 相似文献
308.
Nur Amira Khairil Anwar Muhammad Najmi Mohd Nazri Ahmad Hafiz Murtadha Elis Rosliza Mohd Adzemi Venugopal Balakrishnan Khairul Mohd Fadzli Mustaffa Tengku Ahmad Damitri AI-Astani Tengku Din Maya Mazuwin Yahya Juhara Haron Noor Fatmawati Mokhtar 《Acta biochimica et biophysica Sinica》2021,(8):961-978
Aggressive tissue biopsy is commonly unavoidable in the management of most suspected tumor cases to conclusively verify the presence of cancerous cells through ... 相似文献
309.
310.
Galal Yahya Nashwa Hashem Mohamed Jordi Pijuan Noura M. Seleem Rasha Mosbah Steffen Hess Ahmed A. Abdelmoaty Rafa Almeer Mohamed M. Abdel-Daim Hamoud Shulaywih Alshaman Ibrahim Juraiby Kamel Metwally Zuzana Storchova 《Microbial biotechnology》2021,14(5):2199-2213
Sofosbuvir and Daclatasvir are among the direct-acting antiviral (DAA) medications prescribed for the treatment of chronic hepatitis C (CHC) virus infection as combination therapy with other antiviral medications. DAA-based therapy achieves high cure rates, reaching up to 97% depending on the genotype of the causative hepatitis C virus (HCV). While DAAs have been approved as an efficient and well-tolerated therapy for CHC, emerging concerns about adverse cardiac side effects, higher risk of recurrence and occurrence of hepatocellular carcinoma (HCC) and doubts of genotoxicity have been reported. In our study, we investigated in detail physiological off-targets of DAAs and dissected the effects of these drugs on cellular organelles using budding yeast, a unicellular eukaryotic organism. DAAs were found to disturb the architecture of the endoplasmic reticulum (ER) and the mitochondria, while showing no apparent genotoxicity or DNA damaging effect. Our study provides evidence that DAAs are not associated with genotoxicity and highlights the necessity for adjunctive antioxidant therapy to mitigate the adverse effects of DAAs on ER and mitochondria. 相似文献