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131.
132.
Water disinfection systems utilizing electrolytically generated copper and silver ions (200 and 20, 400 and 40, or 800 and 80 micrograms/liter) and low levels of free chlorine (0.1 to 0.4 mg/liter) were evaluated at room (21 to 23 degrees C) and elevated (39 to 40 degrees C) temperatures in filtered well water (pH 7.3) for their efficacy in inactivating Legionella pneumophila (ATCC 33155). At room temperature, a contact time of at least 24 h was necessary for copper and silver (400 and 40 micrograms/liter) to achieve a 3-log10 reduction in bacterial numbers. As the copper and silver concentration increased to 800 and 80 micrograms/liter, the inactivation rate significantly (P less than or equal to 0.05) increased from K = 2.87 x 10(-3) to K = 7.50 x 10(-3) (log10 reduction per minute). In water systems with and without copper and silver (400 and 40 micrograms/liter), the inactivation rates significantly increased as the free chlorine concentration increased from 0.1 mg/liter (K = 0.397 log10 reduction per min) to 0.4 mg/liter (K = 1.047 log10 reduction per min). Compared to room temperature, no significant differences were observed when 0.2 mg of free chlorine per liter with and without 400 and 40 micrograms of copper and silver per liter was tested at 39 to 40 degrees C. All disinfection systems, regardless of temperature or free chlorine concentration, showed increase inactivation rates when 400 and 40 micrograms of copper and silver per liter was added; however, this trend was significant only at 0.4 mg of free chlorine per liter.  相似文献   
133.
The present study was designed to examine the role of opioid receptors on food choice and macronutrient selection in neonatal chicks. In this study, 13 experiments designed, experiments 1–3 for effect of specific opioid receptors on appetite and experiments 4–13 on effect of opioid receptors on food choice and macronutrient selection in meat-type chick. In experiment 1, chicken intracerebroventricular (ICV) injected with 125, 250 and 500 pmol of DAMGO (µ-opioid receptor agonist). Experiment 2 was conducted to investigate the effect of DPDPE (δ-opioid receptor agonist) at doses of 20, 40 and 80 nmol. In experiment 3 ICV injection of the U-50488H (κ-opioid receptor agonist, of 10, 20 and 40 nmol) was done. In experiment 4, birds injected with saline and different diets: standard diet without fat, diet containing nutrient energy 20 % higher than standard, diet containing nutrient energy 20 % lower than standard and standard diet containing fat were offered to them to investigate desire of chicken to diets. Experiments 5–7 were similar to experiment 4, except, birds ICV injected with 125, 250 and 500 pmol of DAMGO. In experiments 8–10 chicken received ICV injection of DPDPE (20, 40 and 80 nmol). The experiments 11–13 was similar to previous experiments which birds injected with different doses of U-50488H (10, 20 and 40 nmol), respectively. Then the cumulative food intake measured until 180-min post injection. According to the results, ICV injection of DAMGO diminished food intake while DPDPE and U-50488H increased appetite (P < 0.05). Despite anorexigenic effect, ICV injection of DAMGO increased birds desire to eat fat containing standard diet compared to the standard diet without fat (P < 0.05). These findings suggest endogenous opioids governing preferences for fat rich foods.  相似文献   
134.
Tuberculosis(TB) is a disease of global significance, which accounts for a death in every 15 seconds. Recent studies shows TB is rising in certain parts of the world, and Saudi Arabia is one of them. Several factor contribute in predisposing the subjects for infection including but not limited to addiction to various compounds which have immune modulation properties, such as amphetamines and Heroin etc. Khat a plant whose leaves are chewed for its euphoric effect in east Africa and Arabian Peninsula including Saudi Arabia, is considered as mildly addictive, and its principle compound, Cathinone shares structural and functional similarity with amphetamine a known immunomodulator. Tuberculosis being a disease of immune modulation has a varied spectrum of complex interplay of proinflammatory molecules, resistin is one of them. In the present study, we try to explore the trinity of khat addiction, serum resistin level and tuberculosis by correlating the serum resistin level in non khat addicted healthy subjects, khat addicted healthy subjects, and in patients, both khat addicted and non khat addicted, with active tuberculosis. We observed significantly higher resistin level among the apparently healthy khat addicted subjects as compared to non addicted healthy controls. Thereafter, when we compare the resistin levels between khat addicted and non khat addicted TB patients we did not found significant difference between the two groups. However bacillary load was observe to be significantly higher among the khat addicted TB patient as compare to non addicted one. Validation of above results in animal model revealed dose dependant increase in bacillary growth in the Wistar rats treated with khat. Taken together these results suggest the role of khat in immune modulation albeit in the limited frame of resistin level.  相似文献   
135.
Over the past two decades, there has been a notable rise in the use of antipsychotic drugs, as they are used to treat an increasing number of neuropsychiatric disorders. This rise has been led predominantly by greater use of the second generation antipsychotic (SGA) drugs, which have a low incidence of neurological side-effects. However, many SGAs cause metabolic dysregulation, including glucose intolerance and insulin resistance, thus increasing the risk of cardiometabolic disorders. The metabolic effects of the novel SGA lurasidone, which was approved by the Food and Drug Administration in 2010, remain largely unknown. As rodent models accurately predict the metabolic effects of SGAs in humans, the aim of the present study was to use sophisticated animal models of glucose tolerance and insulin resistance to measure the metabolic effects of lurasidone. In parallel, we compared the SGA olanzapine, which has established metabolic effects. Adult female rats were treated with vehicle, lurasidone (0.2, 0.8 or 2.0 mg/kg, s.c.) or olanzapine (10.0 mg/kg, s.c.) and subjected to the glucose tolerance test (GTT). Separate groups of rats were treated with vehicle, lurasidone (0.2, 0.8 or 2.0 mg/kg, s.c.) or olanzapine (1.5 and 15 mg/kg, s.c.) and tested for insulin resistance with the hyperinsulinemic-euglycemic clamp (HIEC). Compared to vehicle treated animals, lurasidone caused mild glucose intolerance in the GTT with a single dose, but there was no effect on insulin resistance in the GTT, measured by HOMA-IR. The HIEC also confirmed no effect of lurasidone on insulin resistance. In contrast, olanzapine demonstrated dose-dependent and potent glucose intolerance, and insulin resistance in both tests. Thus, in preclinical models, lurasidone demonstrates mild metabolic liability compared to existing SGAs such as olanzapine. However, confirmation of these effects in humans with equivalent tests should be confirmed.  相似文献   
136.
CD81 is a ubiquitously expressed member of the tetraspanin family. It forms large molecular platforms, so-called tetraspanin webs that play physiological roles in a variety of cellular functions and are involved in viral and parasite infections. We have investigated which part of the CD81 molecule is required for the formation of domains in the cell membranes of T-cells and hepatocytes. Surprisingly, we find that large CD81 platforms assemble via the short extracellular δ-domain, independent from a strong primary partner binding and from weak interactions mediated by palmitoylation. The δ-domain is also essential for the platforms to function during viral entry. We propose that, instead of stable binary interactions, CD81 interactions via the small δ-domain, possibly involving a dimerization step, play the key role in organizing CD81 into large tetraspanin webs and controlling its function.  相似文献   
137.
Membrane technology is broadly applied in the medical field. The ability of membranous systems to effectively control the movement of chemical entities is pivotal to their significant potential for use in both drug delivery and surgical/medical applications. An alteration in the physical properties of a polymer in response to a change in environmental conditions is a behavior that can be utilized to prepare ‘smart’ drug delivery systems. Stimuli-responsive or ‘smart’ polymers are polymers that upon exposure to small changes in the environment undergo rapid changes in their microstructure. A stimulus, such as a change in pH or temperature, thus serves as a trigger for the release of drug from membranous drug delivery systems that are formulated from stimuli-responsive polymers. This article has sought to review the use of stimuli-responsive polymers that have found application in membranous drug delivery systems. Polymers responsive to pH and temperature have been extensively addressed in this review since they are considered the most important stimuli that may be exploited for use in drug delivery, and biomedical applications such as in tissue engineering. In addition, dual-responsive and glucose-responsive membranes have been also addressed as membranes responsive to diverse stimuli.  相似文献   
138.
The use of chemical tools to validate clinical targets has gained in popularity over recent years and the importance of understanding the activity, selectivity and mechanism of action of these compounds is well recognized. Dysregulation of the HSP70 protein family has been linked to multiple cancer types and drug resistance, highlighting their importance as popular targets for anti-cancer drug development. Apoptozole is a recently identified small molecule, which has been reported to possess strong affinity for the HSP70 isoforms HSP72 and HSC70. We investigated apoptozole as a potential chemical tool for HSP70 inhibition. Unfortunately, using both biochemical and biophysical techniques, we were unable to find any experimental evidence that apoptozole binds to HSP70 in a specific and developable way. Instead, we provide experimental evidence that apoptozole forms aggregates under aqueous conditions that could interact with HSP70 proteins in a non-specific manner.  相似文献   
139.
TETRISO, 0,0-diisopropyl S-2-diisopropylaminoethyl phosphorothiolate, was detoxified by Bacillus cereus T., a gram positive spore forming microorganism. It was found that, after 5 days, a crude soluble fraction of Bacillus cereus T. eliminates up to 92% of acetylcholinesterase inhibition caused by TETRISO, in the concentration range 10-3 to 10-5M.  相似文献   
140.
The current studies were carried out in the three experimental locations of Kashmir valley during 2013 to 2016. The species Andrena cineraria formed the dense nest aggregations in plan grounds, barren lands and hilly areas near the fruit orchards and other landscapes with clay loam soil type. The species start flying and foraging in the orchards from April till July. The nests were allodalous, 29–36 cm in depth, with cells located obliquely around the main barrow. The nests were dense with a maximum density of 11.09 nests/m2 observed in landscapes of Budgam. The barrow diameters were found varying with depth from main entrance. The maximum barrow diameter recorded was 2.05 mm. At certain depth, the female constructs the first cell and the upper nest burrow is vertical and lower is oblique. The nest entrance is generally hidden under the tumulus. In the depth of average 30.48 cm, each cell directly opens to main burrow either alternately or unilaterally. The cell number, diameter, and length varied with depth. Foraging behaviour of A. cineraria on various fruit crops and other shrubs and social forestry trees were determined and the abundance, visitation rate, total visits and time spend per flower were found significant, especially on fruit crops. The significance of the studies is important for the melittologists, as it will help in the conservation of bee fauna. The study is also important in using this species for pollination purpose and would also help to detect and understand the possible pre-adaptation of species in temperate region of Kashmir valley.  相似文献   
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