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51.
Nadia Ali Rimi Rebeca Sultana Kazi Ishtiak-Ahmed Salah Uddin Khan M. A. Yushuf Sharker Rashid Uz Zaman Eduardo Azziz-Baumgartner Emily S. Gurley Nazmun Nahar Stephen P. Luby 《EcoHealth》2014,11(1):83-93
Slaughtering sick poultry is a risk factor for human infection with highly pathogenic avian influenza and is a common practice in Bangladesh. This paper describes human exposures to poultry during slaughtering process and the customs and rituals influencing these practices in two Bangladeshi rural communities. In 2009, we conducted 30 observations to observe slaughtering practices and 110 in-depth and short interviews and 36 group discussions to explore reasons behind those practices. The villagers reported slaughtering 103 poultry, including 20 sick poultry during 2 months. During different stages of slaughtering, humans, the environment, healthy poultry, and other animals were exposed to poultry blood and body parts. Women performed most of the slaughtering tasks, including evisceration. Defeathering required the most time and involved several persons. During festivals, ceremonies, and rituals, many people gathered and participated in the slaughtering of poultry. Exposure to poultry slaughtering created numerous opportunities for potential avian influenza transmission. Strategies that can be further tested to determine if they reduce the risk of transmission include skinning the carcasses of sick poultry, using hot water for defeathering and cleaning, using a bucket to contain slaughtering blood and carcass, burying the offal and encouraging handwashing. 相似文献
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53.
Ben Alaya Bouafif N Ben Salah A Louzir H Zaâtour A Bel Haj Hamida N Mighri F Gharbi A Gramiccia M Gradoni L Dellagi K Ben Ismaïl R 《Archives de l'Institut Pasteur de Tunis》2001,78(1-4):11-16
A cross sectional study aimed to evaluate the effect of antigenic preparation (Leishmania infantum versus Leishmania major) and dose of leishmania antigens (5 x 10(6) versus 2.5 x 10(6) parasites in the same volume) on the reproducibility of delayed type hypersensitivity leishmania skin test. Results showed that among 34 individuals involved from visceral leishmaniasis endemic area. 26 (76.5%) had a positif Leishmania infantum leishmania (L-L. infantum) test and 27 (79.4%) to Leishmania major leishmania (L-L. major). Mean size of cutaneous reaction was 5.94 +/- 2.86 mm for L-L. infantum and 5.41 +/- 3.23 mm for L-L. major, with a significant positive linear association (p < 10-3). Intra-class correlation coefficient was 0.80 (CI95% = [0.64-0.93]) and concordance Kappa (kappa) was 0.57 (CI95% = [0.40-0.74]). Among 153 individuals from zoonotic cutaneous leishmaniasis. 92.9% revealed a positive test for both types of leishmanin (L-L. major full dose versus L-L. major half dose). Mean size of cutaneous reaction was 12.61 +/- 4.65 mm for the reference test and 11.30 +/- 3.95 mm for diluted one, with a positive linear association (p < 10-3). Intra-class correlation coefficient was 0.78 (IC95% = [0.71-0.84]) and concordance Kappa (kappa) was 0.82 (IC95% = [0.73-0.91]). These results demonstrate a limited effect of leishmania antigenic variation and antigen dose on the reproducibility of delayed type hypersensitivity induced by the leishmanin test. 相似文献
54.
Effects of water-deficit on lipids of safflower aerial parts 总被引:1,自引:0,他引:1
Three-week-old plants of safflower (Carthamus tinctorius L.) were subjected to a water-deficit stress. The lipid composition of the shoot parts of both control (well-watered) and water stressed plants was analyzed. Experimental data revealed that moderate stress induced an increase in total lipid content within all lipidic classes. However, severe water-deficit induced a sharp decrease in the total lipid content and specially in polar lipids, particularly in phosphatidylethanolamine, phosphatidylcholine, monogalactosyl-diacylglycerol and digalactosyl-diacylglycerol. Also, the content of neutral lipids was increased. Concerning the fatty acid composition, water-deficit induced a decrease in their degree of unsaturation expressed by a reduction in the proportions of linolenic (18:3) and linoleic (18:2) acids and most of lipidic classes. 相似文献
55.
Two new species of Tachygonetria, T. africana n. sp. and T. pretoriensis n. sp. are described. Both are parasites of Geochelone pardalis (Bell) from South Africa. In addition, two subspecies, T. longicollis fitzsimmonsi Petter, 1966 and T. macrolaimus macrolaimus (Linstow, 1899), also parasites of Geochelone pardalis (from Pretoria Zoo, South Africa), are redescribed and new information on their morphology is presented. On the basis of their morphology, these subspecies are raised to full specific level. 相似文献
56.
Endothelin-3 induced mesenteric vasoconstriction and PMN infiltration in the rat small intestine: role of endothelin receptors 总被引:1,自引:0,他引:1
The objectives of this study were to characterize endothelin (ET)-3-induced alterations in intestinal hemodynamics and to evaluate whether ET-3 administration alters the tissue levels of polymorphonuclear leukocytes (PMNs) and modulates the epithelial barrier function of the small intestine. ET-3 (100 pmol/kg/min) was infused into the superior mesenteric artery (SMA) for 10 min, and tissue samples were obtained 30 min after terminating the infusion. SMA blood flow was significantly decreased throughout the experiment following ET-3 infusion. Pretreatment with bosentan (ET-A and ET-B receptor antagonist), ET-B receptor antagonist BQ-788 or ET-A receptor antagonist BQ-485 completely inhibited the ET-3-induced decrease in the SMA blood flow. Similar results were obtained from the resistance data, in which ET-3-induced increases in SMA resistance were significantly reduced by all ET receptor antagonists. ET-3 administration significantly elevated tissue MPO activity, blood-to-lumen clearance of (51)Cr-EDTA and caused a marked microscopic damage in the intestinal mucosa. ET-3-induced elevations in tissue PMN infiltration and mucosal damage were significantly inhibited by pretreatments with ET-A or ET-B receptor antagonists. Overall, our data indicate that ET-3 causes microscopic damage, PMN infiltration and mucosal dysfunction in the rat small intestine. In addition, ET-3-induced hemodynamic alterations as well as tissue PMN infiltration and mucosal damage are mediated by both ET-A and ET-B receptors. 相似文献
57.
Ayyad SE Sowellim SZ el-Hosini MS Abo-Atia A 《Zeitschrift für Naturforschung. C, Journal of biosciences》2003,58(5-6):333-336
An investigation of the natural products chemistry of the brown alga Sargassum asperifolium from the red sea yielded a new steroidal metabolite, 24-vinyl cholest-4-ene-24-ol-3-one, saringosterone (3), a known steroidal metabolite, 24-vinyl cholest-5-ene-3b,24-diol, saringosterol (4), and known diterpene with a hydroazulene skeleton, dictyone (1). The identification of the isolated metabolites was established mainly by spectral methods and chemical transformation of the dictyone (1) to its acetate (2). 相似文献
58.
Time is considered to be an important encoding dimension in olfaction, as neural populations generate odour-specific spatiotemporal responses to constant stimuli. However, during pheromone mediated anemotactic search insects must discriminate specific ratios of blend components from rapidly time varying input. The dynamics intrinsic to olfactory processing and those of naturalistic stimuli can therefore potentially collide, thereby confounding ratiometric information. In this paper we use a computational model of the macroglomerular complex of the insect antennal lobe to study the impact on ratiometric information of this potential collision between network and stimulus dynamics. We show that the model exhibits two different dynamical regimes depending upon the connectivity pattern between inhibitory interneurons (that we refer to as fixed point attractor and limit cycle attractor), which both generate ratio-specific trajectories in the projection neuron output population that are reminiscent of temporal patterning and periodic hyperpolarisation observed in olfactory antennal lobe neurons. We compare the performance of the two corresponding population codes for reporting ratiometric blend information to higher centres of the insect brain. Our key finding is that whilst the dynamically rich limit cycle attractor spatiotemporal code is faster and more efficient in transmitting blend information under certain conditions it is also more prone to interference between network and stimulus dynamics, thus degrading ratiometric information under naturalistic input conditions. Our results suggest that rich intrinsically generated network dynamics can provide a powerful means of encoding multidimensional stimuli with high accuracy and efficiency, but only when isolated from stimulus dynamics. This interference between temporal dynamics of the stimulus and temporal patterns of neural activity constitutes a real challenge that must be successfully solved by the nervous system when faced with naturalistic input. 相似文献
59.
Hendrickson Steven C. St. Louis James D. Lowe James E. Abdel-aleem Salah 《Molecular and cellular biochemistry》1997,166(1-2):85-94
Long chain free fatty acids (FFA) are the preferred metabolic substrates of myocardium under aerobic conditions. However, under ischemic conditions long chain FFA have been shown to be harmful both clinically and experimentally. Serum levels of free fatty acids frequently are elevated in patients with myocardial ischemia. The proposed mechanisms of the detrimental effects of free fatty acids include: (1) accumulation of toxic intermediates of fatty acid metabolism, such as long chain acyl-CoA thioesters and long chain acylcarnitines, (2) inhibition of glucose utilization, particularly glycolysis, during ischemia and/or reperfusion, and (3) uncoupling of oxidative metabolism from electron transfer. The relative importance of these mechanisms remains controversial. The primary site of FFA-induced injury appears to be the sarcolemmal and intracellular membranes and their associated enzymes. Inhibitors of free fatty acid metabolism have been shown experimentally to decrease the size of myocardial infarction and lessen postischemic cardiac dysfunction in animal models of regional and global ischemia. The mechanism by which FFA inhibitors improve cardiac function in the postischemic heart is controversial. Whether the effects are dependent on decreased levels of long chain intermediates and/or enhancement of glucose utilization is under investigation. Manipulation of myocardial fatty acid metabolism may prove beneficial in the treatment of myocardial ischemia, particularly during situations of controlled ischemia and reperfusion, such as percutaneous transluminal coronary angioplasty and coronary artery bypass grafting. (Mol Cell Biochem 166: 85-94, 1997) 相似文献
60.
Anupam Dutta Elie Bouri Juha Junttila Gazi Salah Uddin 《Global Change Biology Bioenergy》2018,10(9):683-693
The growing interest in biofuel as a green energy source has intensified the linkages between corn and ethanol markets, especially in the United States that represents the largest producing and exporting country for ethanol in the world. In this study, we examine the effect of corn market uncertainty on the price changes of US ethanol applying a set of GARCH‐jump models. We find that the US ethanol price changes react positively to the corn market volatility shocks after controlling for the effect of oil price uncertainty. In addition, we document that the impact of corn price volatility on the US ethanol prices appears to be asymmetric. Specifically, only the positive corn market volatility shocks are found to influence the ethanol market returns. Our findings also suggest that time‐varying jumps do exist in the ethanol market. 相似文献