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71.
An analytical method for flavonoids present in the seed extract of buckwheat (Fagopyrum esculentum Moench, Polygonaceae), using HPLC and a photodiode array detector and interfaced to an electrospray ionisation mass spectrometer, has been developed. Structural information about the flavonols was obtained from the retention time characteristics, the UV-visible spectra and the mass spectra without the need to isolate the individual compounds. The methanol extract of buckwheat contained principally four flavonol glycosides: rutin, quercetin, kaempferol-3-rutinoside and a trace quantity of a flavonol triglycoside. 相似文献
72.
Singh VP Patil CS Jain NK Singh A Kulkarni SK 《Prostaglandins & other lipid mediators》2003,71(3-4):163-175
Inflammatory bowel disease (IBD) is a relapsing inflammation of intestine, which is mediated by release of inflammatory mediators. Both cyclo-oxygenase product prostaglandin (PGE2) and lipo-oxygenase product leukotriene (LTB4), may contribute to the pathogenesis of the inflammatory response. Nimesulide, a preferential COX-2 inhibitor was evaluated for its efficacy against experimental colitis in two different models (acetic acid- and LTB4-induced IBD) in rats. Inflammatory response was induced by intrarectal single administration of acetic acid or LTB4. Nimesulide (9 and 18 mg/kg, p.o.) significantly prevented development of inflammatory changes, decreased myeloperoxidase (MPO) activity, and also restored the altered contractility response of the isolated colon segment to KCl. The results suggested the involvement of both cyclo-oxygenase (COX) and lipo-oxygenase-mediated proinflammatory agents in colonic inflammatory process associated with IBD. Further, this study suggests that such therapeutic interventions may be of value in the treatment of IBD. 相似文献
73.
Ngo LY Patil SD Unadkat JD 《American journal of physiology. Gastrointestinal and liver physiology》2001,280(3):G475-G481
The objectives of our study were to identify the types of nucleoside transporters present in the human fetal small intestine and to characterize their developmental activity, longitudinal distribution, and transport kinetics compared with those present in the adult intestine. Nucleoside uptake by intestinal brush-border membrane vesicles was measured by an inhibitor-stop rapid filtration technique. Only the purine-specific (N1; hCNT2) and the pyrimidine-specific (N2; hCNT1) Na(+)-dependent nucleoside transporters were found to be present on the brush-border membranes of the enterocytes along the entire length of the fetal and adult small intestines. The activity of these transporters was higher in the proximal than in the distal small intestine. Both the N1 and N2 transporters found in the fetal intestine shared similar kinetic properties (Michaelis-Menten constant and Na(+)-nucleoside stoichiometry) to those in the adult intestine. During the period of rapid morphogenesis (11-15 wk gestation), no temporal differences were apparent in the activity of the N1 and N2 transporters in the fetal small intestine. These findings have implications for the absorption of drugs from the amniotic fluid by the fetus after maternal drug administration of nucleoside drugs such as the antivirals zidovudine and didanosine. 相似文献
74.
Role of liquid membrane phenomenon in biological actions of ACE inhibitors, captopril and lisinopril
Nagappa AN Patil RT Pandi V Ziauddin K 《Indian journal of biochemistry & biophysics》2001,38(6):412-416
The liquid membrane phenomenon in angiotensin converting enzyme (ACE) inhibitors namely, captopril and lisinopril has been studied. Hydraulic permeability data have been obtained to demonstrate the existence of the liquid membrane in series with a supporting membrane generated by the ACE inhibitors. Data on the transport of the relevant permeants in presence of the liquid membrane formed by ACE inhibitors indicate that liquid membrane phenomenon is likely to play a significant role in the action of ACE inhibitors. 相似文献
75.
Protein kinase A-dependent phosphorylation of aquaporin-1 总被引:6,自引:0,他引:6
The molecular mechanisms for regulating water balance in many tissues are unknown. Like the kidney, the eye contains multiple water channel proteins (aquaporins) that transport water through membranes, including two (AQP1 and AQP4) in the ciliary body, the site of aqueous humor production. Previous results from our laboratory demonstrated that water channel activity of AQP1 was significantly increased by protein kinase A (PKA) activators such as cyclic-AMP (cAMP) and forskolin. The purpose of this study is to determine whether PKA-dependent protein phosphorylation is involved in the regulation of water channel activity of AQP1. Results presented here suggest that catalytic subunit of protein kinase A significantly increased the amount of phosphorylated AQP1 protein. In addition, these results indicated that cAMP-responsive redistribution of AQP1 may be regulated by phosphorylation of AQP1. Moreover, they provide new insights on the molecular mechanisms for regulating water balance in several tissues involving rapid water transport such as ciliary epithelium. In addition, they suggest important potential roles for AQP1 in several clinical disorders involving rapid water transport such as glaucoma. 相似文献
76.
The prevalence of intermediate coronary artery stenosis (defined as a diameter stenosis of 40% to 70%) is quite large in patients undergoing PTCA. The coronary angiogram is considered the 'gold standard' for the definition of coronary anatomy, in spite of various limitations associated with its use. In recent years, sensor tipped guidewire based methods of physiologic assessment of stenosis severity, like myocardial fractional flow reserve, and poststenotic coronary flow reserve had established their role in the decision making in catheterization laboratory. The decision making should combine morphologic and physiologic assessment as better evidence based approach in guiding therapy to avoid the 'oculostenotic reflex'. 相似文献
77.
Vishwanath M. Patil 《In vitro cellular & developmental biology. Plant》1998,34(3):240-243
Summary The purpose of this study was to developin vitro techniques for conserving wild and endemic species ofCeropegia by mass multiplication for subsequent reintroduction in their natural habitat. Micropropagation involving a combination of
axillary bud culture, shoot multiplication, somatic embryogenesis andin vitro tuber formation forCeropegia jainii, a rare plant of the Indian sub continent,C. bulbosa var.bulbosa andC. bulbosa var.lushii, common species, was developed. Nodal explants from all species were cultured on 0.5 MS medium with 8.8 μM (2 mg·l−1) N6-benzyl aminopurine (BA) to regenerate the axillary buds. These produced multiple shoots when transferred to multiplication
medium consisting of 0.5 MS medium with 2.2 μM (0.5 mg·l−1) BA, or microtubers when transferred to 0.5 MS medium with 22.2 μM (5 mg·l−1) BA and 23.2 μM (5 mg·l−1) kinetin.In vitro flowering occurred inC. jainii and not in the other two varieties when the plants were cultured on multiplication media with spermine at 0.25 μM (50 μg·l−1) as an additive. Shoot pieces produced callus on MS medium with 9.05 μM (2 mg·l−1) 2,4-dichlorophenoxy acetic acid. Regeneration of the calli by somatic embryogenesis was achieved when they were transferred
to 0.5 MS medium with 2.2 μM (0.5 mg·l−1) BA. Rooting of the shoots was possible both byin vitro andex vitro means. 相似文献
78.
B G Patil D V Gokhale K B Bastawde U S Puntambekar S G Patil 《Journal of industrial microbiology & biotechnology》1998,21(6):307-310
Tamarind wastes such as tamarind husk, pulp, seeds, fruit and the effluent generated during tartaric acid extraction were
used as supplements to evaluate their effects on alcohol production from cane molasses using yeast cultures. Small amounts
of these additives enhanced the rate of ethanol production in batch fermentations. Tamarind fruit increased ethanol production
(9.7%, w/v) from 22.5% reducing sugars of molasses as compared to 6.5% (w/v) in control experiments lacking supplements after
72 h of fermentation. In general, the addition of tamarind supplements to the fermentation medium showed more than 40% improvement
in ethanol production using higher cane molasses sugar concentrations. The direct fermentation of aqueous tamarind effluent
also yielded 3.25% (w/v) ethanol, suggesting its possible use as a diluent in molasses fermentations. This is the first report,
to our knowledge, in which tamarind-based waste products were used in ethanol production.
Received 2 April 1998/ Accepted in revised form 13 November 1998 相似文献
79.
Saikat Boliar Supratik Das Manish Bansal Brihaspati N. Shukla Shilpa Patil Tripti Shrivastava Sweety Samal Sandeep Goswami C. Richter King Jayanta Bhattacharya Bimal K. Chakrabarti 《PloS one》2015,10(3)
An ideal HIV-1 Env immunogen is expected to mimic the native trimeric conformation for inducing broadly neutralizing antibody responses. The native conformation is dependent on efficient cleavage of HIV-1 Env. The clade B isolate, JRFL Env is efficiently cleaved when expressed on the cell surface. Here, for the first time, we report the identification of a native clade C Env, 4-2.J41 that is naturally and efficiently cleaved on the cell surface as confirmed by its biochemical and antigenic characteristics. In addition to binding to several conformation-dependent neutralizing antibodies, 4-2.J41 Env binds efficiently to the cleavage-dependent antibody PGT151; thus validating its native cleaved conformation. In contrast, 4-2.J41 Env occludes non-neutralizing epitopes. The cytoplasmic-tail of 4-2.J41 Env plays an important role in maintaining its conformation. Furthermore, codon optimization of 4-2.J41 Env sequence significantly increases its expression while retaining its native conformation. Since clade C of HIV-1 is the prevalent subtype, identification and characterization of this efficiently cleaved Env would provide a platform for rational immunogen design. 相似文献
80.
Erdenebileg Uyangaa Jin Hyoung Kim Ajit Mahadev Patil Jin Young Choi Seong Bum Kim Seong Kug Eo 《PLoS pathogens》2015,11(11)
Type I interferon (IFN-I)-dependent orchestrated mobilization of innate cells in inflamed tissues is believed to play a critical role in controlling replication and CNS-invasion of herpes simplex virus (HSV). However, the crucial regulators and cell populations that are affected by IFN-I to establish the early environment of innate cells in HSV-infected mucosal tissues are largely unknown. Here, we found that IFN-I signaling promoted the differentiation of CCL2-producing Ly-6Chi monocytes and IFN-γ/granzyme B-producing NK cells, whereas deficiency of IFN-I signaling induced Ly-6Clo monocytes producing CXCL1 and CXCL2. More interestingly, recruitment of Ly-6Chi monocytes preceded that of NK cells with the levels peaked at 24 h post-infection in IFN-I–dependent manner, which was kinetically associated with the CCL2-CCL3 cascade response. Early Ly-6Chi monocyte recruitment was governed by CCL2 produced from hematopoietic stem cell (HSC)-derived leukocytes, whereas NK cell recruitment predominantly depended on CC chemokines produced by resident epithelial cells. Also, IFN-I signaling in HSC-derived leukocytes appeared to suppress Ly-6Ghi neutrophil recruitment to ameliorate immunopathology. Finally, tissue resident CD11bhiF4/80hi macrophages and CD11chiEpCAM+ dendritic cells appeared to produce initial CCL2 for migration-based self-amplification of early infiltrated Ly-6Chi monocytes upon stimulation by IFN-I produced from infected epithelial cells. Ultimately, these results decipher a detailed IFN-I–dependent pathway that establishes orchestrated mobilization of Ly-6Chi monocytes and NK cells through CCL2-CCL3 cascade response of HSC-derived leukocytes and epithelium-resident cells. Therefore, this cascade response of resident–to-hematopoietic–to-resident cells that drives cytokine–to-chemokine–to-cytokine production to recruit orchestrated innate cells is critical for attenuation of HSV replication in inflamed tissues. 相似文献