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51.
Kazi TG Jalbani N Kazi N Arain MB Jamali MK Afridi HI Kandhro GA Sarfraz RA Shah AQ Ansari R 《Biological trace element research》2009,127(1):16-27
The determination of toxic metals (TMs) in the biological samples of human beings is an important clinical screening procedure.
The aim of this work is to determine total content of TMs, aluminum (Al), cadmium (Cd), nickel (Ni), and lead (Pb) in scalp
hair samples of chronic kidney male patients (CKPs) on maintenance hemodialysis, during the period of 2005–2007. The study
included 115 CKPs (all smokers) and 150 controls or referents [82 (nonsmokers) and 68 (smokers)]. Both controls and patients
(males) were of the same age group (ranged 25–55 years), socioeconomic status, localities, and dietary habits. The scalp hair
samples were analyzed by electrothermal atomic absorption spectrometer, prior to microwave-induced acid digestion. The accuracy
of the total Al, Cd, Ni, and Pb measurements was tested by simultaneously analyzing certified reference material (human hair
NCS ZC81002). No significant differences were observed between the analytical results and the certified values (paired t test at p > 0.05). The levels of TMs in scalp hair samples of patients were found to be higher as compared to control nonsmoker and
smokers. Moreover, the study shows that levels of Al, Cd, Ni, and Pb in scalp hair samples may be useful to evaluate the impact
of cigarette smoking in kidney failure patients. 相似文献
52.
YIT ARN TEH OLIVIER MAZÉAS ALYSSA R. ATWOOD TRIFFID ABEL ROBERT C. RHEW 《Global Change Biology》2009,15(2):330-345
The Arctic tundra has been shown to be a potentially significant regional sink for methyl chloride (CH3Cl) and methyl bromide (CH3Br), although prior field studies were spatially and temporally limited, and did not include gross flux measurements. Here we compare net and gross CH3Cl and CH3Br fluxes in the northern coastal plain and continental interior. As expected, both regions were net sinks for CH3Cl and CH3Br. Gross uptake rates (−793 nmol CH3Cl m−2 day−1 and −20.3 nmol CH3Br m−2 day−1) were 20–240% greater than net fluxes, suggesting that the Arctic is an even greater sink than previously believed. Hydrology was the principal regulator of methyl halide flux, with an overall trend towards increasing methyl halide uptake with decreasing soil moisture. Water table depth was one of the best predictors of net and gross uptake, with uptake increasing proportionately with water table depth. In drier areas, gross uptake was very high, averaging −1201 nmol CH3Cl m−2 day−1 and −34.9 nmol CH3Br m−2 day−1; in flooded areas, gross uptake was significantly lower, averaging −61 nmol CH3Cl m−2 day−1 and −2.3 nmol CH3Br m−2 day−1. Net and gross uptake was greater in the continental interior than in the northern coastal plain, presumably due to drier inland conditions. Within certain microtopographic features (low‐ and high‐centered polygons), uptake rates were positively correlated with soil temperature, indicating that temperature played a secondary role in methyl halide uptake. Incubations suggested that the inverse relationship between water content and methyl halide uptake was the result of mass transfer limitation in saturated soils, rather than because of reduced microbial activity under anaerobic conditions. These findings have potential regional significance, as the Arctic is expected to become warmer and drier due to anthropogenic climate forcing, potentially enhancing the Arctic sink for CH3Cl and CH3Br. 相似文献
53.
Tasneem Gul Kazi Ghulam Abbas Kandhro Hassan Imran Afridi Naveed Kazi Jameel Ahmed Baig Mohammad Balal Arain Abdul Qadir Shah Nasreen Syed Sham Kumar Nida Fatima Kolachi Sumaira Khan 《Biological trace element research》2010,134(3):265-279
In many developing countries, men and women are at high risk of goiter and iron deficiency. The aim of the recent study is to assess the interaction of (Cu), with iron (Fe), iodine/iodide (I), and thyroid hormones in goitrous patients. Sixty goitrous male (GMPs) and 72 female patients (GFPs) were evaluated for the Cu, Fe, I, and thyroid hormones status in biological samples (serum and urine), and compared to non-goitrous subjects of both genders (M?=?106, F?=?120). The biological samples were analyzed for Cu and Fe concentration using atomic absorption spectrometer, while I was measured by the potentiometric method, prior to microwave-assisted acid digestion (MD). Quality control for the method was established with certified samples. Significantly higher mean values of Cu in serum, and urine samples of GMPs and GFPs, while lower value of Fe and I were observed as compared to control subjects (p?<?0.015), respectively. The mean values of free triiodothyronine (FT3) and free thyroxin (FT4) were found to be lower in goitrous patients of both genders than in the age-matched healthy controls (p?<?0.006 and 0.002), respectively, in contrast high mean values of thyroid-stimulating hormone (TSH) were detected in patients (p?<?0.009), as compared to non-goitrous subjects. It was observed that the deficiencies of Fe, I, and thyroid hormone in goitrous patients could be influenced by efficiency of Cu. 相似文献
54.
Qadir Jasiya Majid Sabhiya Khan Mosin S. Wani Mumtaz Din 《Molecular biology reports》2021,48(4):3313-3325
Molecular Biology Reports - Vitamin D receptor (VDR) mediates cellular processes like cell cycle arrest and apoptosis which effect cancer susceptibility. VDR single nucleotide polymorphisms (SNPs)... 相似文献
55.
JAUME FLEXAS JOSEFINA BOTA JOSEP CIFRE JOSÉ MARIANO ESCALONA JERONI GALMÉS JAVIER GULÍAS EL-KADRI LEFI SARA FLORINDA MARTÍNEZ-CAÑELLAS MARÍA TERESA MORENO MIQUEL RIBAS-CARBÓ DIEGO RIERA BARTOLOMÉ SAMPOL HIPÓLITO MEDRANO 《The Annals of applied biology》2004,144(3):273-283
Photosynthetic down-regulation and/or inhibition under water stress conditions are determinants for plant growth, survival and yield in drought-prone areas. Current knowledge about the sequence of metabolic events that leads to complete inhibition of photosynthesis under severe water stress is reviewed. An analysis of published data reveals that a key regulatory role for Rubisco in photosynthesis is improbable under water stress conditions. By contrast, the little data available for other Calvin cycle enzymes suggest the possibility of a key regulatory role for some enzymes involved in the regeneration of RuBP. There are insufficient data to determine the role of photophosphorylation. Several important gaps in our knowledge of this field are highlighted. The most important is the remarkable scarcity of data about the regulation/inhibition of photosynthetic enzymes other than Rubisco under water stress. Consequently, new experiments are urgently needed to improve our current understanding of photosynthetic down-regulation under water stress. A second gap is the lack of knowledge of photosynthetic recovery after irrigation of plants which have been subjected to different stages of water stress. This knowledge is necessary in order to match physiological down-regulation by water stress with controlled irrigation programmes. 相似文献
56.
Sami Ullah Farooq Anwar Muhammad Fayyaz ur Rehman Rahman Qadir Muhammad Safwan Akram 《化学与生物多样性》2023,20(7):e202300107
This article presents an optimized ultrasound-assisted ethanolic extraction (UAEE) and characterization of selected high-value components from Gemlik olive fruit (GOF) harvested from Potohar region of Pakistan. Response surface methodology (RSM), involving central composite design (CCD), was applied to optimize the extraction variables i. e., temperature (25–65 °C), extraction time (15–45 min) and aqueous ethanol concentration (60–90 %) for optimal recovery of bioactives extract, total phenolic contents (TPC) and DPPH free radical scavengers. Under the optimized set of conditions such as 43 °C temperature, 32 min extraction time and 80 % aqueous ethanol, the best extract yield (218.82 mg/g), TPC (19.87 mg GAE/g) and DPPH scavenging activity (63.04 %) were recorded. A quadratic polynomial model was found to be reasonably fitted to the observed results for extract yield (p<0.0001 and R2=0.9941), TPC (p<0.0001 and R2=0.9891), and DPPH radical scavenging activity (p<0.0001 and R2=0.9692). Potent phenolic compounds were identified by GC/MS in GOF extract and considerable amount of essential fatty acids were also detected. The current findings support the use of UAEE as an effective green route for optimized recovery of high-value components from GOF and hence its applications can be extended to functional food and nutra-pharmaceutical developments. 相似文献
57.
Hydroxyurea was used to study the proliferation rate of haemopoietic stem cells (CFUJ in normal mice, after irradiation or transplantation into irradiated recipients. It was demonstrated that the proliferation rate of endogenous CFUS (endo-CFU,) and exogenous CFUS (exo-CFUs) are identical. After irradiation (650 R) the surviving endo-CFUs begin to proliferate immediately. By contrast exo-CFU, transplanted into the irradiated recipient mouse (850 R), begin to proliferate only after about 30 hr. However, injection of isoproterenol (which stimulates adenyl cyclase) or dibutyryl cyclic adenosine 3′,5′-monophosphate shortly after marrow cell graft, triggers the transplanted CFUS into cell cycle as shown by an almost immediately increased sensitivity to hydroxyurea. Isoproterenol is capable of inducing DNA synthesis also in stem cells of normal mice but it takes about 20 hr before CFU, become to be increasingly sensitive to hydroxyurea. 相似文献
58.
BK McFarlin AS Venable RR Williams AW Jackson 《Biology of sport / Institute of Sport》2015,32(1):11-14
Exercising or working in a hot, humid environment can results in the onset of heat-related illness when an individual''s temperature is not carefully monitored. The purpose of the present study was to compare three techniques (data loggers, thermal imaging, and wired electrodes) for the measurement of peripheral (bicep) and central (abdominal) skin temperature. Young men and women (N = 30) were recruited to complete the present study. The three skin temperature measurements were made at 0 and every 10-min during 40-min (60% VO2max) of cycling in a hot (39±2°C), humid (45±5% RH) environment. Data was statistically analyzed using the Bland-Altman method and correlation analysis. For abdominal skin temperature, the Bland-Altman limits of agreement indicated that data loggers (1.5) were a better index of wired than was thermal imaging (3.5), For the bicep skin temperature the limits of agreement was similar between data loggers (1.9) and thermal (1.9), suggesting the both were suitable measurements. We also found that when skin temperature exceeded 35°C, we observed progressively better prediction between data loggers, thermal imaging, and wired skin sensors. This report describes the potential for the use of data loggers and thermal imaging to be used as alternative measures of skin temperature in exercising, human subjects. 相似文献
59.
Arisha Mohamed Hamed Hui Yan Ahmad Muhammad Qadir Wei Tang Meng Kou Yaju Liu Xin Wang Yungang Zhang Qiang Li 《Plant Molecular Biology Reporter》2021,39(3):473-488
Plant Molecular Biology Reporter - Sweetpotato (Ipomoea batatas L), the herbaceous plant cultivated for its starchy storage roots, has a complex genome (2n?=?6x?=?90) with... 相似文献