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101.
Currently, hyperhomocysteinemia is a well-known risk factor for variety of vascular diseases. Prevalence of
hyperhomocysteinemia increases with age. Hence, the present study was aimed to investigate the prevalence of
hyperhomocysteinemia in healthy upper socio-economic class population in India. Total homocysteine (tHcy) concentration was
determined in 1243 (906 men & 337 women) healthy Indian doctors with different age group. Using Third National Health and
Nutrition Examination Survey (NHANES III) study criteria, the prevalence of hyperhomocysteinemia was 92.85% among men
(>11.4 µmol/L) and 81.60% among women (>10.4 µmol/L). The prevalence of hyperhomocysteinemia was higher among men with
mean tHcy concentration (21.96 ± 0.38 µmol/L) significantly higher (P<0.0001) than women (15.90 ± 0.39 µmol/L) (95% CI, 4.733-
7.376). Our study showed very high prevalence of hyperhomocysteinemia which may point to the future risk for various
pathologies in the present subset of population. Further studies to look at the plasma levels of homocysteine lowering vitamins are
warranted to prevent the future risk of vascular diseases. 相似文献
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Arenahalli Ningegowda Madhu Prashant Giribhattanavar Mandayam Singara Narayan Siddalingaiya Gurudutt Prapulla 《Biotechnology letters》2010,32(4):503-506
Vitamin B12 was produced by probiotic Lactobacillus plantarum in submerged fermentation (96 h) with successive anaerobic and aerobic phases of 48 h each to give 13 ng vitamin B12/g dry biomass. Sodium cyanide-mediated cell lysis, followed by benzyl alcohol/chloroform/water extraction, improved the release
of intracellular vitamin B12 for analysis. The presence of the K+ adduct of cyanocobalamin (m/z of 1394) was established using electron spray ionization–mass spectra; growth of a mutant of Escherichia coli in the presence of cyanocobalamin ascertained its bioavailability. 相似文献
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Pradhi Rajeev Prashant Rajput Dharmendra Kumar Singh Amit Kumar Singh 《人类与生态风险评估》2018,24(6):1453-1463
This study reports health risk assessment of PM1-bound carcinogenic hexavalent chromium [Cr(VI)] from central part of Indo-Gangetic plain (IGP) (PM1: particulate matter with aerodynamic diameter ≤1µm). Cr(VI) concentration has been estimated utilizing spectrophotometer with a modified novel method. Average ratio of Cr(VI)/CrT was 0.39 ± 0.07 (CrT: Total chromium) in the central IGP (Kanpur). Our study reports that mass fraction of Cr(VI) averaging at 0.39 is ~3 times higher than that assumed conventionally [Cr(VI)/CrT: 1/7]. Cancer risk assessment has been performed by assessing excess cancer risk (ECR) for the Cr(VI). ECR determined due to Cr(VI) was 57 and 14.3 (in one million) for adults and children, respectively. Our study suggests that risk due to Cr(VI) reported in previous studies were being underestimated by a factor of three. The Cr(VI)/CrT average ratio of 0.39 determined in this study was utilized to calculate risk assessment due to Cr(VI) from other locations in the IGP. Owing to large population of India (~125 million), the cancer risk due to Cr(VI) inhalation itself would become very significant. Thus, future research should focus on metal speciation of PM-bound samples from different locations to better constraint the toxicological risk assessment on a regional-to-global scale. 相似文献
105.
Vikas Kumar Mrinal Kashyap Shristy Gautam Prashant Shukla Khashti Ballabh Joshi Vandana Vinayak 《Journal of biosciences》2018,43(4):717-729
Diatoms are photosynthetic unicellular microalgae and are nature’s hidden source of several biosynthetic metabolites with their use in biofuel, food and drug industries. They mainly contain various lipids, sterols, isoprenoids and toxins with their use in apoptotic, fertility controlling and cancer drugs. Chemical studies on diatoms are limited due to various limitations such as variation of nutrients, contaminants and change in seasonal factors in the environment. To overcome these limitations, we obtained axenic cultures of 12 fresh-water diatom strains on the 22nd day of inoculation having a dry weight of 1 mg each and performed their Fourier transform infrared (FTIR) study for the detection of functional groups responsible for their chemical moiety. The spectral mapping showed a varied level of polyunsaturated fatty acids, amides, amines, ketone bodies and esters for their applications in various pharmacological, food and biofuel industries in the exponential phase of their growth in f/2 media. The FTIR study of the 12 diatom strains showed various similarities in the form of some common peak patterns ranging from 3000 to 3600 cm?1 for νO–H absorption. The symmetric stretching vibration frequency of Diadesmis confervaceae (V2) type species showed different behaviour than others in the spectral region starting from 1600 to 1700 cm?1. The absorption between 1500 and 1575 cm?1 reflects the presence of the –N–H group. Infrared (IR) absorptions falling between 1600 and 1700 cm?1 reflect the presence of amide’s νC=O in all species. Placoneis elginensis (V8) type species showed an additional absorption band which is centred around 1735–1750 cm?1 which perhaps reflects the presence of ester’s νC=O. Diadesmis confervaceae (V2), Nitzschia palea (V4), Placoneis elginensis (V8), Nitzschia palea var. debilis (V6), Nitzschia inconspicua (V10), Gomphonema parvulum (V11) and Sellaphora (V12) showed distinct structural features with important key functionalities that can make them essential drug markers in the pharmaceutical industry. 相似文献
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The cell cycle of neurons remains suppressed to maintain the state of differentiation and aberrant cell cycle reentry results in loss of neurons, which is a feature in neurodegenerative disorders like Alzheimer''s disease (AD). Present studies revealed that the expression of microRNA 34a (miR-34a) needs to be optimal in neurons, as an aberrant increase or decrease in its expression causes apoptosis. miR-34a keeps the neuronal cell cycle under check by preventing the expression of cyclin D1 and promotes cell cycle arrest. Neurotoxic amyloid β1–42 peptide (Aβ42) treatment of cortical neurons suppressed miR-34a, resulting in unscheduled cell cycle reentry, which resulted in apoptosis. The repression of miR-34a was a result of degradation of TAp73, which was mediated by aberrant activation of the MEK extracellular signal-regulated kinase (ERK) pathway by Aβ42. A significant decrease in miR-34a and TAp73 was observed in the cortex of a transgenic (Tg) mouse model of AD, which correlated well with cell cycle reentry observed in the neurons of these animals. Importantly, the overexpression of TAp73α and miR-34a reversed cell cycle-related neuronal apoptosis (CRNA). These studies provide novel insights into how modulation of neuronal cell cycle machinery may lead to neurodegeneration and may contribute to the understanding of disorders like AD. 相似文献