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1.
Seema Bhargava Sathnur Pushpakumar Naira Metreveli Srikanth Givvimani Suresh C. Tyagi 《Molecular biology reports》2014,41(8):4889-4898
Hyperhomocysteinemia (HHcy) is associated with cognitive decline and hearing loss due to vascular dysfunction. Although we have shown that HHcy-induced increased expression of matrix metalloproteinase-9 (MMP-9) is associated with cochlear pathology in cystathionine-β-synthase heterozygous (CBS+/?) mice, it is still unclear whether MMP-9 contributes to functional deficit in cognition and hearing. Therefore, we hypothesize that HHcy-induced MMP-9 activation causes vascular, cerebral and cochlear remodeling resulting in diminished cognition and hearing. Wildtype (WT), CBS+/?, MMP-9?/? and CBS+/?/MMP-9?/? double knock-out (DKO) mice were genotyped and used. Doppler flowmetry of internal carotid artery (ICA) was performed for peak systolic velocity [PSV], pulsatility index [PI] and resistive index [RI]. Cognitive functions were assessed by Novel Object Recognition Test (NORT) and for cochlear function Auditory brainstem response (ABR) was elicited. Peak systolic velocity, pulsatility and resistive indices of ICA were decreased in CBS+/? mice, indicating reduced perfusion. ABR threshold was increased and maximum ABR amplitude and NORT indices (recognition, discrimination) were decreased in CBS+/? mice compared to WT and MMP-9?/?. All these parameters were attenuated in DKO mice suggesting a significant role of MMP-9 in HHcy-induced vascular, neural and cochlear pathophysiology. Regression analysis of PSV with ABR and cognitive parameters revealed significant correlation (0.44–0.58). For the first time, MMP-9 has been correlated directly to functional deficits of brain and cochlea, and found to have a significant role. Our data suggests a dual pathology of HHcy occurring due to a decrease in blood supply (vasculo-neural and vasculo-cochlear) and direct tissue remodeling. 相似文献
2.
M S Jawahar S Sivasubramanian V K Vijayan C V Ramakrishnan C N Paramasivan V Selvakumar S Paul S P Tripathy R Prabhakar 《BMJ (Clinical research ed.)》1990,301(6748):359-362
OBJECTIVE--To assess the efficacy of a short course chemotherapy regimen for treating tuberculosis of the lymph nodes in children. DESIGN--Open, collaborative, outpatient clinical trial. SETTING--Outpatient department of the Tuberculosis Research Centre, paediatric surgery departments of the Institute of Child Health and Hospital for Children and the Government Stanley Hospital, Madras, South India. PATIENTS--Children aged 1-12 years with extensive, multiple site, superficial tuberculous lymphadenitis confirmed by biopsy (histopathology or culture). INTERVENTIONS--Patients were treated with a fully supervised intermittent chemotherapy regimen consisting of streptomycin, rifampicin, isoniazid, and pyrazinamide three times a week for two months followed by streptomycin and isoniazid twice a week for four months on an outpatient basis. Surgery was limited to biopsy of nodes for diagnosis and assessment. MAIN OUTCOME MEASURES--Response to chemotherapy was assessed by regression of lymph nodes and healing of sinuses and abscesses during treatment and follow up. Compliance with treatment and frequency of adverse reactions were also estimated. RESULTS--197 Patients were admitted to the study and 168 into the analysis. The regimen was well tolerated and compliance was good with 101 (60%) patients receiving the prescribed chemotherapy within 15 days of the stipulated period of six months. Those whose chemotherapy extended beyond that period received the same total number of doses. Clinical response was favourable in most patients at the end of treatment. Sinuses and abscesses healed rapidly. Residual lymphadenopathy (exceeding 10 mm diameter) was present in 50 (30%) patients at the end of treatment; these nodes were biopsied. Fresh nodes, increase in size of nodes, and sinuses and abscesses occurred both during treatment and follow up. After 36 months of follow up after treatment only 5 (3%) patients required retreatment for tuberculosis. CONCLUSION--Tuberculous lymphadenitis in children can be successfully treated with a short course chemotherapy regimen of six months. 相似文献
3.
Chloroplast Biogenesis 60 : Conversion of Divinyl Protochlorophyllide to Monovinyl Protochlorophyllide in Green(ing) Barley, a Dark Monovinyl/Light Divinyl Plant Species 总被引:3,自引:2,他引:1 下载免费PDF全文
In higher plants, most of the chlorophyll a is formed via the divinyl and monovinyl chlorophyll monocarboxylic biosynthetic routes. These two routes are strongly interconnected prior to protochlorophyllide formation in barley (Hordeum vulgare L. cv Morex), a dark monovinyl-light divinyl plant species, but not in cucumber (Cucumis sativus L. cv Beit Alpha MR), a dark divinyl-light divinyl plant species (BC Tripathy, CA Rebeiz, 1986 J Biol Chem 261: 13556-13564). It is shown that in dark monovinyl-light divinyl plant species such as barley, the divinyl and monovinyl monocarboxylic routes become interconnected at the level of protochlorophyllide during transition from the divinyl to the monovinyl protochlorophyllide biosynthetic mode. In cucumber, a dark divinyl-light divinyl plant species, in which the monovinyl monocarboxylic biosynthetic route becomes preponderant only after an abnormally long sojourn in darkness, the conversion of divinyl to monovinyl protochlorophyllide does not take place on the barley time-scale of incubation. 相似文献
4.
A highly sensitive spectrofluorometric method for quantitative estimation of certain precursors of chlorophyll biosynthesis from the mixtures of plant tetrapyrroles having overlapping fluorescence emission spectra is developed. At room temperature (293 degrees K) protoporphyrin IX is monitored from its emission maximum, 633 nm, when excited at 400 nm (E400/F633). Protochlorophyllide is estimated at 638 nm, while being excited at 440 nm (E440/F638). Mg-protoporphyrin+Mg-protoporphyrin monoester pool has emission around 589-592 nm. Therefore the integration value of the emission band that extends from 580 to 610 nm is taken to calibrate its concentration. This spectrofluorometric method designed for the determination of protoporphyrin IX, esterified and nonesterified Mg-protoporphyrin pool, and protochlorophyllide is far superior to available spectrophotometric methods and estimates as low as 1 nM concentration of plant pigments. As minute quantities of individual pigments can be quantitatively analyzed from their mixtures, this method eliminates analytical uncertainties due to recovery losses caused by chromatography. However, only dilute samples can be estimated by this spectrofluorometric method as the quantitative relation between fluorescence and concentration deviates from linearity at high, i.e., above 150 nM, concentrations of pigment to be quantified. 相似文献
5.
6.
N. Basavaraja M. C. Nandeesha T.J. Varghese P. Keshavanath G. K. Srikanth 《Zeitschrift fur angewandte Ichthyologie》1990,6(1):46-50
The efficacy of the synthetic estrogen, diethylstilbestrol (DES), for sex-reversal in the Java tilapia, Oreochromis mossambicus was investigated. Fry of 8–10 mm total length were fed diets containing 25, 50 and 100 ppm of DES for 30 days in plastic pools; this was followed by 45–65 days rearing in fertilized cement cisterns where hormone-free diet was given. DES at 50 and 100 ppm induced 100% sex-reversal; DES at 25 ppm resulted in only a slightly larger proportion of females to males. The untreated control group had a higher proportion of males than females. No intersex or sterile individuals were observed among the steroid-treated fish. The present investigation demonstrates that 50 ppm DES administered for 30 days is sufficient to induce a 100% sex-reversal in O. mossambicus. 相似文献
7.
Ni2+ inhibits electron-transport activity of isolated barley chloroplasts and this inhibition of electron transport by Ni2+ is distinctly different from other heavy metal ion (e.g., Pb2+, Cd2+, Zn2+)-induced inhibition of chloroplast function. Ni2+ inactivates Photosystem II (PS II) activity at a lower concentration than that required for the same extent of inhibition of Photosystem I (PS I)-mediated electron flow. Ni2+ induces changes in chlorophyll a (Chl a) emission characteristics and brings about a lowering of the Chl a fluorescence yield, and this lowering of Chl a fluorescence intensity is not relieved by the exogenously supplied electron donor NH2OH which donates electrons very close to the PS II reaction centres. Immobilization of the chloroplast membrane structure with glutaraldehyde fails to arrest the Ni2+-induced loss of PS II activity. Also, Ni2+-treated chloroplasts do not regain the ability to photoreduce 2,6-dichlorophenolindophenol even after washing of chloroplasts with buffer. These results indicate that unlike Zn2+ or Pb2+, Ni2+ induces alterations in the chloroplast photosynthetic apparatus resulting in an irreversible loss of electron-transport activity. 相似文献
8.
Khan Md. Idrish Raja Kamilya Dibyendu Choudhury Tanmoy Gon Tripathy Partha Sarathi Rathore Gaurav 《Probiotics and antimicrobial proteins》2021,13(6):1572-1584
Probiotics and Antimicrobial Proteins - In this study, a bacterial strain COFCAU_P1, isolated from the digestive tract of a freshwater teleost rohu (Labeo rohita), was identified as Bacillus... 相似文献
9.
Sudhanshu S. Yadav Elesela Srikanth Neetu Singh Sushma Rathaur 《Parasitology international》2013,62(2):193-198
The glutathione reductase (GR) and thioredoxin reductase (TrxR) are important enzymes of the redox system that aid parasites to maintain an adequate intracellular redox environment. In the present study, the enzyme activity of GR and TrxR was investigated in Setaria cervi (S. cervi). Significant activity of both enzymes was detected in the somatic extract of adult and microfilariae stages of S. cervi. Both GR and TrxR were separated by partial purification using ammonium sulfate fractionation and DEAE ion exchange chromatography suggesting the presence of both glutathione and thioredoxin systems in S. cervi. The enzyme glutathione reductase (ScGR) was purified to homogeneity using affinity and ion exchange chromatography that resulted in 90 fold purification with a yield of 11.54%. The specific activity of the ScGR was 643 U/mg that migrated as a single band on SDS-PAGE. The subunit molecular mass was determined to be ~ 50 kDa while the optimum pH and temperature were found to be 7.0 and 35 °C respectively. The activation energy (Ea) was calculated from the slope of Arrhenius plot as 16.29 ± 1.40 kcal/mol. The Km and Vmax were determined to be 0.27 ± 0.045 mM; 30.30 ± 1.30 U/ml with NADPH and 0.59 ± 0.060 mM; 4.16 ± 0.095 U/ml with GSSG respectively. DHBA, a specific inhibitor for GR has completely inhibited the enzyme activity at 1 μM concentration. The inhibition of ScGR activity with NAI (IC50 0.71 mM), NEM (IC50 0.50 mM) and DEPC (IC50 0.27 mM) suggested the presence of tyrosine, cysteine and histidine residues at its active site. Further studies on characterization and understanding of these antioxidant enzymes may lead to designing of an effective drug against lymphatic filariasis. 相似文献
10.
Renu Goel Krishna R Murthy Srinivas M Srikanth Sneha M Pinto Mitali Bhattacharjee Dhanashree S Kelkar Anil K Madugundu Gourav Dey Sujatha S Mohan Venkatarangaiah Krishna TS Keshava Prasad Shukti Chakravarti HC Harsha Akhilesh Pandey 《Clinical proteomics》2013,10(1):9