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2.
Serum antioxidant enzyme activity in Parkinson's disease 总被引:2,自引:0,他引:2
Jawahar Kalra Ali H. Rajput Subrahmanyam V. Mantha Kailash Prasad 《Molecular and cellular biochemistry》1992,110(2):165-168
Summary The activities of superoxide dismutase (SOD; EC 1.15.1.1) and glutathione peroxidase (GSHPx; EC 1.11.1.9.), the enzymes that metabolize the superoxide anion and hydrogen peroxide, respectively, were measured in serum
from healthy subjects and patients with Parkinson's disease (PD). The activities of SOD and GSHPx in patients with PD were higher than those in normal healthy individuals. These results suggest that the increased activities
of these enzymes could be due to oxidative stress in the initial stages of this disease. 相似文献
3.
An in vitro procedure for large scale multiplication of Sterculia urens Roxb. (Gum Kadaya Tree) has been developed using cotyledonary node segments. An average of 4.0 shoots per node were obtained on Murashige and Skoog's (MS) medium containing 2.0 mgl–1 6-benzyl amino-purine (BAP) within 21 days of initial culture. Upon subsequent subculture 16 shoots/node could be harvested every three weeks and upto three times. Sixty per cent of the shoots were successfully rooted. Rooted plantlets were transferred to plastic pots containing soil under mist house conditions before they were finally exposed to an external environment. Fifty seven per cent of the plantlets survived in nursery sheds. 相似文献
4.
Protoplasma - Picrorhiza kurroa Royle ex Benth is a valuable medicinal herb of North-Western Himalayas due to presence of two major bioactive compounds, picroside-I and picroside-II used in the... 相似文献
5.
Shah, Ashish R., Thomas G. Keens, and David Gozal.Effect of supplemental oxygen on supramaximal exercise performance and recovery in cystic fibrosis. J. Appl.Physiol. 83(5): 1641-1647, 1997.The effects ofsupplemental O2 on recovery fromsupramaximal exercise and subsequent performance remain unknown. Ifrecovery from exercise could be enhanced in individuals with chroniclung disease, subsequent supramaximal exercise performance could also be improved. Recovery from supramaximal exercise and subsequent supramaximal exercise performance were assessed after 10 min of breathing 100% O2 or room air(RA) in 17 cystic fibrosis (CF) patients [25 ± 10 (SD) yrold, 53% men, forced expired volume in 1 s = 62 ± 21%predicted] and 17 normal subjects (25 ± 8 yr old, 59% men,forced expired volume in 1 s = 112 ± 15% predicted). Supramaximalperformance was assessed as the work of sustained bicycling at a loadof 130% of the maximum load achieved during a graded maximal exercise.Peak minute ventilation(E) andheart rate (HR) were lower in CF patients at the end of eachsupramaximal bout than in controls. In CF patients, single-exponentialtime decay constants indicated faster recovery of HR(HR = 86 ± 8 and 73 ± 6 s in RA and O2,respectively, P < 0.01). Similarly, fast and slow time constants of two-exponential equations providing thebest fit for ventilatory recovery were improved in CF patients duringO2 breathing ( = 132.1 ± 10.5 vs. 82.5 ± 10.4 s; = 880.3 ± 300.1 vs. 368.6 ± 107.1 s,P < 0.01). However, no such improvements occurred in controls. Supramaximal performance after O2 improved in CF patients (109 ± 6% of the 1st bout after O2 vs. 94 ± 6% in RA, P < 0.01).O2 supplementation had no effect on subsequent performance in controls (97 ± 3% inO2 vs. 93 ± 3% in RA). Weconclude that supplemental O2after a short bout of supramaximal exercise accelerates recovery andpreserves subsequent supramaximal performance in patients with CF. 相似文献
6.
Mausumi Mutsuddi Debasish Mutsuddi A. S. Mukherjee Ashish K. Duttagupta 《Chromosoma》1984,89(1):55-62
The chromosome complement of hybrid males from the cross between Drosophila miranda female and D. persimilis male provides an interesting chromosomal situation where an autosome, the 3rd chromosome of D. persimilis, coexists with a homologue that developed into a sex chromosome, the X2 in D. miranda. Except for certain inversions and a few minor translocations, these two chromosomes (X2 and the 3rd) still look alike as polytene elements. However, in hybrid males pairing of the two chromosomes, the X2 and 3rd, is rare, while in female hybrids it occurs frequently. — 3H-TdR labeling shows that while the X2 and 3rd chromosomes replicate synchronously in hybrid female, in the hybrid male the former completes its replication earlier than the 3rd chromosome, as do the two arms of the X1 (XL and XR). The frequency and relative intensity of 3H-TdR labeling of each site of the X2 and that of the 3rd chromosome in hybrid males closely agree with those of the corresponding sites in the X2 of the miranda male and the 3rd chromosome of the persimilis male (or female), respectively. The results suggest that timing and rate of replication of the X2 are determined autonomously and follow the pattern in the respective parental species. 相似文献
7.
Jason D. Roh Nicholas Houstis Andy Yu Bliss Chang Ashish Yeri Haobo Li Ryan Hobson Carolin Lerchenmüller Ana Vujic Vinita Chaudhari Federico Damilano Colin Platt Daniel Zlotoff Richard T. Lee Ravi Shah Michael Jerosch‐Herold Anthony Rosenzweig 《Aging cell》2020,19(6)
Heart failure with preserved ejection fraction (HFpEF) is the most common type of HF in older adults. Although no pharmacological therapy has yet improved survival in HFpEF, exercise training (ExT) has emerged as the most effective intervention to improving functional outcomes in this age‐related disease. The molecular mechanisms by which ExT induces its beneficial effects in HFpEF, however, remain largely unknown. Given the strong association between aging and HFpEF, we hypothesized that ExT might reverse cardiac aging phenotypes that contribute to HFpEF pathophysiology and additionally provide a platform for novel mechanistic and therapeutic discovery. Here, we show that aged (24–30 months) C57BL/6 male mice recapitulate many of the hallmark features of HFpEF, including preserved left ventricular ejection fraction, subclinical systolic dysfunction, diastolic dysfunction, impaired cardiac reserves, exercise intolerance, and pathologic cardiac hypertrophy. Similar to older humans, ExT in old mice improved exercise capacity, diastolic function, and contractile reserves, while reducing pulmonary congestion. Interestingly, RNAseq of explanted hearts showed that ExT did not significantly modulate biological pathways targeted by conventional HF medications. However, it reversed multiple age‐related pathways, including the global downregulation of cell cycle pathways seen in aged hearts, which was associated with increased capillary density, but no effects on cardiac mass or fibrosis. Taken together, these data demonstrate that the aged C57BL/6 male mouse is a valuable model for studying the role of aging biology in HFpEF pathophysiology, and provide a molecular framework for how ExT potentially reverses cardiac aging phenotypes in HFpEF. 相似文献
8.
Pratima Yadav Kumar Ranjeet Tewari Ashish Kumar 《Russian Journal of Bioorganic Chemistry》2020,46(6):1148-1155
Russian Journal of Bioorganic Chemistry - In the present studies, novel pyrazole derivatives have been synthesized linked through various linkers for the anti-inflammatory evaluation. The... 相似文献
9.
Sunanda Mallick Ashish Kumar Hiren Dodia Cyrus Alexander Dileep Vasudevan Tushar
Kant Beuria 《Bioscience reports》2021,41(1)
The peptidoglycan (PG) layer is an intricate and dynamic component of the bacterial cell wall, which requires a constant balance between its synthesis and hydrolysis. FtsEX complex present on the inner membrane is shown to transduce signals to induce PG hydrolysis. FtsE has sequence similarity with the nucleotide-binding domains (NBDs) of ABC transporters. The NBDs in most of the ABC transporters couple ATP hydrolysis to transport molecules inside or outside the cell. Also, this reaction cycle is driven by the dimerization of NBDs. Though extensive studies have been carried out on the Escherchia coli FtsEX complex, it remains elusive regarding how FtsEX complex helps in signal transduction or transportation of molecules. Also, very little is known about the biochemical properties and ATPase activities of FtsE. Because of its strong interaction with the membrane-bound protein FtsX, FtsE stays insoluble upon overexpression in E. coli, and thus, most studies on E. coli FtsE (FtsEEc) in the past have used refolded FtsE. Here in the present paper, for the first time, we report the soluble expression, purification, and biochemical characterization of FtsE from E. coli. The purified soluble FtsE exhibits high thermal stability, exhibits ATPase activity and has more than one ATP-binding site. We have also demonstrated a direct interaction between FtsE and the cytoplasmic loop of FtsX. Together, our findings suggest that during bacterial division, the ATPase cycle of FtsE and its interaction with the FtsX cytoplasmic loop may help to regulate the PG hydrolysis at the mid cell. 相似文献
10.
Mahendran Ganesan Kumar Deepak Verma Sanjeet Kumar Chandran Ashish Warsi ·Zafar Iqbal Husain Zakir Afroz Shama Rout Prasant Kumar Rahman Laiq Ur 《Plant Cell, Tissue and Organ Culture》2021,146(2):423-423
Plant Cell, Tissue and Organ Culture (PCTOC) - 相似文献