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141.
Qiong Qin Kiran A. Patil Karsten Gronert Sansar C. Sharma 《Prostaglandins, leukotrienes, and essential fatty acids》2008,79(6):201-207
Neuroprotectin D1 (NPD1), a docosahexaenoic acid-derived autacoid, is an endogenous neuroprotective and anti-inflammatory mediator that is generated in the retina and brain. The effects of exogenous NPD1 on retinal ganglion cell (RGC) apoptosis and the role of 12/15-lipoxygenase (Alox15) in retina were evaluated after optic nerve transection (ONT). Treatment with NPD1 was associated with significant protection against RGC death. The percentage of RGC survival in NPD1-treated group was 30% at 2 weeks after ONT as compared with 12% of RGC survival in the ONT group without treatment. Endogenous NPD1 was a predominant lipid autocoid in uninjured and axotomized retinas. Alox15 mRNA expression was upregulated in retinas following ONT suggesting that amplification of 12/15-lipoxygenase (12/15-LOX) may represent a neuroprotective response in the rat retina. The density of RGCs was higher in the normal retina of 12/15-LOX-deficient mice as compared with congenic controls. Hence, the resident NPD1 has a potential role in the physiological and pathophysiological responses of the retina. 相似文献
142.
Aminoglycoside resistance in six clinically isolated Staphylococcus aureus was evaluated. Genotypical examination revealed that three isolates (HLGR-10, HLGR-12, and MSSA-21) have aminoglycoside-modifying
enzyme (AME) coding genes and another three (GRSA-2, GRSA-4, and GRSA-6) lacked these genes in their genome. Whereas isolates
HLGR-10 and HLGR-14 possessed bifunctional AME coding gene aac(6′)-aph(2′′), and aph(3′)-III and showed high-level resistance to gentamycin and streptomycin, MSSA-21 possessed aph(3′)-III and exhibited low resistance to gentamycin, streptomycin, and kanamycin. The remaining three isolates (GRSA-2, GRSA-4, and
GRSA-6) exhibited low resistance to all the aminoglycosides because they lack aminoglycoside-modifying enzyme coding genes
in their genome. The transmission electron microscopy of the three isolates revealed changes in cell size, shape, and septa
formation, supporting the view that the phenomenon of adaptive resistance is operative in these isolates. 相似文献
143.
C-Phycocyanin and allophycocyanin of Spirulina platensis are fractionated and purified using a non-chromatographic method namely, aqueous two phase extraction for the first time. Optimized process parameters of aqueous two phase extraction (PEG 4000/potassium phosphate of tie line length 18.64% with a phase volume ratio 1.45) resulted in pure C-phycocyanin and allophycocyanin with a purity of 3.23 and 0.74, respectively, in a single extraction. Multiple extractions (two) improved the purity of C-phycocyanin from 3.23 to 4.02. Integration of aqueous two phase extraction with membrane process not only facilitated the separation of phase forming components from the products and also increased the purity of allophycocyanin from 0.74 to 1.5. 相似文献
144.
Patil S Bukiya AN Li W Dopico AM Miller D 《Bioorganic & medicinal chemistry letters》2008,18(11):3427-3430
Physiological and pharmacological agents that activate large conductance, voltage-, and calcium-gated potassium (BK) channels located in the smooth muscle are effective vasodilators. Thus, activators of smooth muscle BK channels may be potential therapeutic tools to treat cardiovascular disease associated with vasoconstriction and/or impaired dilation, such as cerebrovascular spasm and constriction. We previously showed that lithocholic acid (LC) and other cholane derivatives activated smooth muscle BK channels and, thus, caused endothelium-independent cerebral artery dilation. However, clinical use of these cholane derivatives could be limited by the actions of these steroids, such as elevation of intracellular calcium and induction of apoptosis. Using LC as template, we designed and synthesized a series of hydroxy-alkynoic acids and corresponding methyl esters, as putative, non-steroid BK channel activators. Indeed, the newly synthesized compounds effectively and reversibly activated rat cerebrovascular myocyte BK channel at concentrations similar to those found effective with LC. Among all the novel compounds tested, C-10 hydroxy-alkynoic acid methyl ester appears to be the most effective activator of vascular myocyte BK channels. 相似文献
145.
146.
He Lijun Zhang Jinsha He Chengyun Zhao Boyang Chen Weizhong Patil Sunil R. 《Molecular and cellular biochemistry》2021,476(3):1599-1603
Molecular and Cellular Biochemistry - DNA hydroxymethylation plays a very important role in some biological processes, such as DNA methylation process. In addition, its presence can also cause some... 相似文献
147.
Specific neuronal expression of human NGF receptors in the basal forebrain and cerebellum of transgenic mice 总被引:3,自引:0,他引:3
Transgenic mice carrying multiple copies of the human NGF receptor gene have been generated. Using a monoclonal antibody specific for the human receptor, we have detected specific expression in cholinergic neurons in the basal forebrain and Purkinje cells in the cerebellum during the postnatal period. Expression in the PNS was exemplified by immunostaining of sympathetic and sensory neurons during an early embryonic age. Transection of the sciatic nerve in transgenic animals resulted in induction of human NGF receptors, indicating that the inserted gene can be appropriately regulated. These transgenic mice will provide an opportunity to study the elements regulating the NGF receptor. Furthermore, the ability to obtain specific expression in transgenic mice will permit directed expression of heterologous genes in discrete cells important in the cholinergic septal-hippocampal pathway and the PNS. 相似文献
148.
149.
K Prakash S D Patil S N Hegde 《Archives internationales de physiologie et de biochimie》1982,90(4):255-264
In the pigeon, 70-80% of the activities of maltase (alpha-D-glucoside glucohydrolase EC 3.2.1.20), sucrase (alpha-glucohydrolase, EC 3.2.1.48), isomaltase (dextran 6-alpha-D-glucan hydrolase, EC 3.2.1.10) and glucoamylase (1,4-alpha-D-glucan glucohydrolase, EC 3.2.1.3) were found to be localized in the brush-border membrane of intestinal epithelial cells. Of the total glycosidase activities in the mucosal homogenate, nearly 60 to 70% were recovered in the microsomal (105 000 X g) fraction, about 30% in the mitochondrial (22 000 X g) fraction and less than 5% from the cytosol (105 000 X g supernatant) fraction. The hydrolases were solubilized by digestion with papain but not with trypsin, and the phosphate ion had a protective effect in the solubilization. Amongst detergents, Triton X-100 but not sodium deoxycholate, was found to truly solubilize these enzymes. 相似文献
150.