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131.

The combined exposure to aluminum (Al) and cadmium (Cd) causes more pronounced adverse health effects on humans. The kidneys are the main organs affected by internal exposure to Cd and Al via food and non-food items. The objective of present study was to measure the Al and Cd concentrations in cigarettes tobacco (branded and non-branded) and drinking water (domestic treated, ground and lake water) samples in southern part of Pakistan, to assess the risk due to ingestion of water and inhalation of cigarettes smoke containing high concentrations of both elements. The study population (kidney disorder and healthy) divided into two group based on consuming lake and ground water, while smoking non-branded cigarette as exposed, while drinking domestic treated water and smoking branded cigarette as non-exposed. Electrothermal atomic absorption spectrometry was used to determined Cd and Al concentrations in tobacco, drinking water and blood samples. The resulted data indicated that the levels of Al and Cd in lake and underground water were higher than the permissible limit in drinking water recommended by the World Health Organization. The biochemical parameters of exposed and referent patients, especially urinary N-acetyl-h-glucosaminidase, were used as a biomarkers of kidney disorder. Exposed kidney disorder patients have higher levels of Cd and Al than the exposed referents subjects, while difference was significant when compared to resulted data of non-exposed patients and referents (p = 0.01–0.001). The pearson correlation showed positive correlation between both toxic element concentrations in water, cigarettes versus blood samples of exposed subjects (r = 0.20–0.67 and 0.71–0.82), while lower values were observed for non-exposed subjects (r = 0.123–0.423 and 0.331–0.425), respectively.

  相似文献   
132.
Green-lipped mussels, Perna viridis, were collected from the eastern and western parts of the Johore Straits in September 2004 and January 2005. Based on the heavy metal concentrations in the different soft tissues (gonad, foot, mantle, gills, muscle, and remaining soft tissues) of these mussel samples, the eastern part of the Johore Straits (which is divided into two portions by a causeway), recorded higher levels of bioavailability and contamination by Cd, Cu, Fe, Ni, and Zn when compared to the western part, while Kg. Pasir Puteh in the eastern part was found to record the highest bioavailability and contamination by heavy metals. The use of different soft tissues of P. viridis as biomonitors of bioavailability and contamination by Cd, Cu, Fe, Pb, Ni, and Zn in the semi-enclosed Johore Straits is proposed, since erroneous results due to spawning and the problem of defecation before dissection could be overcome. Hence, a more accurate interpretation of the bioavailability and contamination by heavy metals in coastal waters could be obtained. To our knowledge, this is the most detailed study on the bioavailability and contamination of heavy metals in the Johore Straits on the Malaysian side of the waterway carried out by using the different soft tissues and metal distribution based on the Mussel Watch approach.  相似文献   
133.
Melanin is responsible for pigmentation of skin and hair. It protects the skin from the harmful effects of UV radiation; however, its abnormal production may lead to different diseases such as hyper-pigmentation or vitiligo. Tyrosinase is a key enzyme in melanin production, therefore inhibitors of this enzyme should have broad application. Due to the adverse effects of synthetic inhibitors currently being used, the search for new inhibitors, especially natural ones, is needed. The methanolic extracts of 80 plants were tested for their tyrosinase inhibitory activities by spectrophotometry at 492?nm. The inhibition mode of effective plant extracts was determined using the Lineweaver-Burk plots. Among these plant extracts, Alhagi camelorum (camel thorn), Camelia sinensis (green tea), Cuminum cyminum (Cumin), Lawsonia inermis (henna), Quercus infectoria (masso), and Vaccinium arctostaphylos (Caucasian whortleberry) were identified as tyrosinase inhibitors with inhibitory effect of more than 50% at concentrations of 1.14?g?L?1. The inhibition mode of four newly found effective plant extracts showed that A. camelorum and V. arctostaphylos inhibit the enzyme in a competitive manner whereas L. inermis and Q. infectoria have mixed inhibitory effect. To recommend these plant extracts for hyper-pigmentation disorders and other applications, further in vitro and in vivo studies are needed.  相似文献   
134.
A study was conducted to determine the effects of long-term exposure to carbofuran on erythrocyte and liver acetylcholinesterase (AChE) activity in Cyprinus carpio, and assess which tissue was more sensitive to pesticide exposure examining this enzyme. Fish were allowed to accilimatize in toxicant-free water for 24 days after 60-day exposure. AChE activity was determined with a spectrophotometer using acetylthiocholine iodide as a substrate in erythrocytes and liver. Enzymic activity of erythrocytes and liver decreased over time. A higher degree of enzyme inhibition was observed in erythrocyte compared to liver. The degree of enzyme inhibition was positively correlated with exposure time. When exposed fish were transferred to clean water, recovery was greater in erythrocytes than liver. Erythrocyte AChE activity recovered after 18 days, while it required 21 days in liver. The findings of this study indicate that erythrocyte AChE is more sensitive to carbofuran than liver. The greater sensitivity of erythrocyte AChE suggests that it may be more useful as a biomarker for monitoring status of pollution in freshwater bodies.  相似文献   
135.
Oxidative stress and antioxidant responses of crucian carp, upon chronic exposure to endosulfan, were evaluated in vivo. The lethal concentration (LC50–96?h) was 70 μg L?1; on its basis, the fish were exposed to endosulfan at 20, 35, and 50 μg L?1 and autopsy was done on days 1, 2, 3, 4, 7, 14, 21, 28, and 35. Lipid peroxidation was induced in a concentration-dependent manner, being highest at 50 μg L?1 (3/4 LC50–96 h, sub-lethal concentration-I, SL-I) on day 4 (720% versus control), followed in its extent (490%) at 30 μg L?1 (1/2 LC50–96 h, sub-lethal concentration-II, SL-II) on day 7 and lowest (260%) at 10 μg L?1 (1/4 LC50–96 h, sub-lethal concentration-III, SL-III) on day 14. Glutathione showed a concentration- and time-dependent elevation in the initial phase, with highest level on day 4 (180%) at SL-I, but showed significant reduction in all test concentrations from day 21 of post-exposure. Superoxide dismutase was decreased significantly throughout the study, with highest reduction (63%) on day 4 at SL-I; catalase increased in all test concentrations up to day 14 but showed a significant decrease from the day 28 of post-exposure. The potential role of these parameters as indicators of pesticide pollution in aquatic systems is discussed.  相似文献   
136.
The purpose of this research is to obtain optimal processing conditions for the adsorption of Remazol Brilliant Violet-5R (RBV-5R) dye onto activated carbon prepared from periwinkle shells (PSAC) by chemical activation with KOH using response surface methodology. Central composite design (CCD) was used to determine the effects of three preparation variables; CO2 activation temperature, CO2 activation time and KOH:char impregnation ratio (IR) on two responses; percentage RBV-5R dye removal and PSAC yield. Based on the CCD, two quadratic models were developed for percentage RBV-5R dye removal and PSAC yield, respectively. The most influential factor on each experimental design response was identified from the analysis of variance (ANOVA). The optimum conditions for the adsorption of RBV-5R dye onto PSAC were CO2 activation temperature of 811 °C, CO2 activation time of 1.70 h and IR of 3.0, resulting in 81.28% RBV-5R dye removal and 28.18% PSAC yield. PSAC prepared under optimum conditions was mesoporous with a Brunauer–Emmett–Teller surface area of 1894 m2·g?1, total pore volume of 1.107 cm3·g?1 and average pore diameter of 2.32 nm. The surface morphology and functional groups of the activated carbon were respectively determined from the scanning electron microscopy and Fourier transform infrared analysis.  相似文献   
137.
A highly sensitive enzyme immunoassay was standardized for aflatoxin B1 determination in poultry feed and its components using Riedel-de-Haen, ELISA Systems. A microtitration plate method was optimized using anti-aflatoxin B1 antibodies and peroxidase – aflatoxin B1 conjugate, based on competitive enzyme immunoassay principle. Standards of concentrations of 5, 10, 20, 50, 100, 500?ng/L aflatoxin B1, prepared in phosphate-buffered saline, were used. Standard curves showed that as the concentration of antigen decreased, absorbance values increased. Fifty percent inhibition was observed at 37?ng/L. Regression analysis showed that log concentration was inversely related to %B/B0, with a highly significant negative correlation (?0.980). The lowest detection limit for aflatoxin B1 was 5?ng/L. Using this standardized ELISA, aflatoxin B1 was detected in most of the commercially available poultry feed samples and their components.

The data suggest that this test is suitable for the accurate determination of aflatoxin B1 concentrations in poultry feed and its components.  相似文献   
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High population rise and climate changes are increasing issues of agricultural production and food safety. Nanotechnology is finding revolutionary applications to improve agricultural and food systems, notably for better crop production and food preservation. Here we review research, industrial and patent trends of nanoscience in food and agriculture. In a literature survey, we found 44.6% publications in the nano-food research area during the years 2013–2015 and 59.09% publications in the nano-agriculture research area during 2012–2015. USA is leading in the development of nanotechnology firms with a maximum share of 75.5% of the total firms, followed by Germany and France with 8.10 and 4.74%, respectively. USA is leading in the nano-food research with 22 granted patents, whereas China is placed first in nano-agriculture research with 28 granted patents during assessment years 2011–2015. Nano-food research focused mainly on nano-food packaging with 76.84% contributions, whereas in nano-agriculture research, focus has been on nano-fertilizers with 90% contributions. Germany, France, Korea, Italy, Czech Republic, Slovenia and Slovak republic have more than 20% of dedicated nanotechnology firms. A growth of about 45% in nano-food patents has been observed for USA during 2011–2015, and China is leading in the nano-agriculture patents with an increase of 60.7% during 2012–2015.  相似文献   
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