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1.
Abid Ali Khaskheli Aysun Cebeci Aydin Sana Jawaid Muhammad Ali Surhio Hassan Imran Afridi 《Bioscience, biotechnology, and biochemistry》2017,81(10):2002-2008
Conjugated linoleic acid (CLA) has attracted as novel type of fatty acids having unusual health-promoting properties such as anticarcinogenic and antiobesitic effects. The present work employed castor oil as substrate for one-pot production of CLA using washed cells of Lactobacillus plantarum (L. plantarum) and lipases as catalysts. Among the screened lipases, the lipase Rhizopus oryzae (ROL) greatly assisted resting cells to produce CLA. Mass spectral analysis of the product showed that two major isomers of CLA were produced in the reaction mixture i.e. cis-9, trans-11 56.55% and trans-10, cis-12 43.45%. Optimum factors for CLA synthesis were found as substrate concentration (8 mg/mL), pH (6.5), washed cell concentration (12% w/v), and incubation time of 20 h. Hence, the combination of ROL with L. plantarum offers one pot production of CLA selectively using castor oil as a cost-effective substrate. 相似文献
2.
Jafar Rezaie Reza Rahbarghazi Milad Pezeshki Mahdi Mazhar Farshid Yekani Majid Khaksar Elhameh Shokrollahi Hassan Amini Shahriar Hashemzadeh Sadiye Emel Sokullu Mehmet Tokac 《Journal of cellular physiology》2019,234(12):21732-21745
Extracellular vesicles (EVs) are nano-sized vesicles, released from many cell types including cardiac cells, have recently emerged as intercellular communication tools in cell dynamics. EVs are an important mediator of signaling within cells that influencing the functional behavior of the target cells. In heart complex, cardiac cells can easily use EVs to transport bioactive molecules such as proteins, lipids, and RNAs to the regulation of neighboring cell function. Cross-talk between intracardiac cells plays pivotal roles in the heart homeostasis and in adaptive responses of the heart to stress. EVs were released by cardiomyocytes under baseline conditions, but stress condition such as hypoxia intensifies secretome capacity. EVs secreted by cardiac progenitor cells and cardiosphere-derived cells could be pinpointed as important mediators of cardioprotection and cardiogenesis. Furthermore, EVs from many different types of stem cells could potentially exert a therapeutic effect on the damaged heart. Recent evidence shows that cardiac-derived EVs are rich in microRNAs, suggesting a key role in the controlling of cellular processes. EVs harboring exosomes may be clinically useful in cell-free therapy approaches and potentially act as prognosis and diagnosis biomarkers of cardiovascular diseases. 相似文献
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Fatemat Hassan Gerard J. Nuovo Melissa Crawford Prosper N. Boyaka Stephen Kirkby Serge P. Nana-Sinkam Estelle Cormet-Boyaka 《PloS one》2012,7(11)
The Cystic Fibrosis Transmembrane conductance Regulator (CFTR) is a chloride channel that plays a critical role in the lung by maintaining fluid homeostasis. Absence or malfunction of CFTR leads to Cystic Fibrosis, a disease characterized by chronic infection and inflammation. We recently reported that air pollutants such as cigarette smoke and cadmium negatively regulate the expression of CFTR by affecting several steps in the biogenesis of CFTR protein. MicroRNAs (miRNAs) have recently received a great deal of attention as both biomarkers and therapeutics due to their ability to regulate multiple genes. Here, we show that cigarette smoke and cadmium up-regulate the expression of two miRNAs (miR-101 and miR-144) that are predicted to target CFTR in human bronchial epithelial cells. When premature miR-101 and miR-144 were transfected in human airway epithelial cells, they directly targeted the CFTR 3′UTR and suppressed the expression of the CFTR protein. Since miR-101 was highly up-regulated by cigarette smoke in vitro, we investigated whether such increase also occurred in vivo. Mice exposed to cigarette smoke for 4 weeks demonstrated an up-regulation of miR-101 and suppression of CFTR protein in their lungs. Finally, we show that miR-101 is highly expressed in lung samples from patients with severe chronic obstructive pulmonary disease (COPD) when compared to control patients. Taken together, these results suggest that chronic cigarette smoking up-regulates miR-101 and that this miRNA could contribute to suppression of CFTR in the lungs of COPD patients. 相似文献
5.
Jing Hu Wail M. Hassan Guorong Chen Yanlin Li Wenqiao Fan Wei Wang 《Ecological Entomology》2019,44(6):800-809
1. The Qilian Mountains represent one of the key livestock‐raising grasslands in China. The two main herbivore species raised in this area – yaks and sheep – are of critical economical value. Grasshoppers compete with these animals for available nutrients, creating multifaceted relationships between livestock, grasshoppers and plants. A clear understanding of such relationships is lacking and is urgently needed to guide conservation efforts. 2. This study aims to document the effects of yak and sheep grazing on grasshopper assemblages and to elucidate the underlying mechanisms of such effects. 3. It is shown here that yaks and sheep impact grasshopper assemblages differently. Grasshopper assemblages exhibited lower density, biodiversity, richness, and evenness of distribution in yak‐grazed pastures than in grazing‐free grasslands. Sheep‐grazed pastures exhibited a dramatically divergent picture, with elevated density, biodiversity and richness, and a slightly decreased evenness of distribution. Grasshoppers were generally larger in grazed pastures than in grazing‐free grasslands, especially in yak‐grazed plots. 4. The present study suggests that differences between yak and sheep pastures in plant assemblage structure and plant traits are probably the underlying forces driving the differences in grasshopper assemblage structure and grasshopper traits, respectively. 5. The study shows that the grasshopper habitat indicator species differ between yak and sheep pastures, raising the possibility that such indicators can be used to monitor grassland usage and degradation in the Qilian Mountains. 6. These results provide novel insights into the dynamic interactions of common domesticated herbivore species, grasshoppers and plants in Qilian Mountains, which augment current knowledge and may ultimately lead to better conservation practices. 相似文献
6.
The histamine-infusion test was conducted in 50 subjects with a modification that allowed the completeness of recovery of the maximal gastric secretion to be assessed. The effects of the exact position of the tube and the position of the subject on the completeness of recovery were investigated. A simple water-recovery test was found to be as reliable as fluoroscopy for showing that the tip of the tube was within the stomach. Provided that the tip was within the stomach, the exact position of the tube did not affect recovery. Furthermore, recovery in 19 subjects was not appreciably affected by changing the person from the left lateral to the supine semirecumbent position. 相似文献
7.
The incidence of postoperative deep vein thrombosis diagnosed by radioisotope scanning in 100 Sudanese patients aged 40 or over was 12%. This compares with an incidence of nearly 30% in 542 patients reported from British hospitals using the same diagnostic technique. The reason for the difference is obscure and needs further investigation. 相似文献
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Dispersal and field progeny production of Trichogramma species released in an olive orchard in Egypt
Esmat Hegazi Wedad Khafagi Annette Herz Maria Konstantopoulou Serif Hassan Essam Agamy Atwa Atwa Sania Shweil 《BioControl》2012,57(4):481-492
Dispersal ability and field progeny production of augmentative released biological control agents depend on ecological adaptations of the particular species or strains used. Four species of the egg parasitoid genus Trichogramma were compared aiming to select suitable candidates for control of lepidopteran olive pests. Three of them (T. bourarachae Pintureau and Babault, T. cordubensis Vargas and Cabello, T. euproctidis Girault) had been previously collected from olive groves, whereas the commercially available strain used (T. evanescens Westwood) was originally isolated from sugarcane fields. During five consecutive field releases in an olive orchard near Cairo, dispersal and/or progeny production of these species was monitored using sentinel eggs placed at different heights in the release tree canopies as well as in neighboring trees (“distance effect”). The cardinal direction of dispersal was random for T. euproctidis and T. evanescens. Significant higher parasitism occurred on sentinel eggs placed on the middle part of tree canopy and highest parasitism was observed in trees where wasps had been released. Field progeny production was highest for T. bourarachae, followed by T. euproctidis and T. cordubensis. T. evanescens propagated less under field conditions. Inter-tree dispersal of all species except T. bourarachae was limited and, for biological control, releasing material should therefore be distributed on each olive tree, preferably also at different levels of the canopy. 相似文献
10.
Waseem Hassan Mohammad Ibrahim Joao Batista Teixeira Rocha 《Chemico-biological interactions》2009,182(1):52-58
As an extension of our previous work we not only evaluated the relationship between acidosis and lipid peroxidation in rat's kidney homogenate, but also determined for the first time the potential anti-oxidant activity of diphenyl diselenide, diphenyl ditelluride and ebselen at a range of pH values (7.4–5.4). Because of the pH dependency of iron redox cycling, pH and iron need to be well controlled and for the reason we tested a number of pH values (from 7.4 to 5.4) to get a closer idea about the role of iron under various pathological conditions. Acidosis increased rate of lipid peroxidation in the absence Fe (II) in kidney homogenates especially at pH 5.4. This higher extent of lipid peroxidation can be explained by; the mobilized iron which may come from reserves where it is weakly bound. Addition of iron (Fe) chelator desferoxamine (DFO) to reaction medium completely inhibited the peroxidation processes at all studied pH values including acidic values (5.8–5.4). In the presence of Fe (II) acidosis also enhanced detrimental effect of Fe (II) especially at pH (6.4–5.4). Diphenyl diselenide significantly protected lipid peroxidation at all studied pH values, while ebselen offered only a small statistically non-significant protection. The highest anti-oxidant potency was observed for diphenyl ditelluride. These differences in potencies were explained by the mode of action of these compounds using their catalytic anti-oxidant cycles. However, changing the pH of the reaction medium did not alter the anti-oxidant activity of the tested compounds. This study provides evidence for acidosis catalyzed oxidative stress in kidney homogenate and for the first time anti-oxidant potential of diphenyl diselenide and diphenyl ditelluride not only at physiological pH but also at a range of acidic values. 相似文献