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31.
Microbial proteolytic enzyme is one of the most important industrial enzymes that hydrolyze proteins. The applications of proteases under harsh industrial conditions like alkalinity, salinity, and temperature make them inactive and unstable. This suggests need for search for novel microbial sources for protease production having diverse properties. For this purpose, 54 bacterial strains were isolated from different salt mines of Karak, Pakistan and were investigated for their proteolytic activity on skim milk agar plates. The strain which showed maximum protease activity was characterized by 16S rRNA gene sequence analysis. Furthermore, growth and protease production was optimized for the characterized bacteria under different physical factors, i.e., pH, temperature and salinity. The isolate BLK-1.5 exhibited strong protease production and was identified as Bacillus subtilis based on biochemical characteristics and 16S rRNA gene sequence analysis. Maximum production of protease was recorded at pH 10, 37 °C and 7 % (w/v) NaCl. Molecular weight of proteases was estimated 38 kDa and its optimum activity was observed at pH 10, 50 °C and 2 % (w/v) NaCl. In conclusion, the protease produced by halo-tolerant Bacillus subtilis strain BLK-1.5 has diverse characteristics and could be useful in various industrial applications.  相似文献   
32.
Human dietary exposure to benzo(a)pyrene (BaP) has generated interest with regard to the association of BaP with gastrointestinal carcinogenesis. Since colon cancer ranks third among cancer-related mortalities, it is necessary to evaluate the effect of phytochemicals on colon cancer initiation and progression. In this study, we investigated the preventive effects of resveratrol (RVT) on BaP-induced colon carcinogenesis in ApcMin mouse model. For the first group of mice, 100 μg BaP/kg body weight was administered to mice in peanut oil via oral gavage over a 60-day period. For the second group, RVT was coadministered with BaP at a dose of 45 μg/kg. For the third group, RVT was administered for 1 week prior to BaP exposure for 60 days. Jejunum, colon and liver were collected at 60 days post BaP and RVT exposure; adenomas in jejunum and colon were counted and subjected to histopathology. RVT reduced the number of colon adenomas in BaP+RVT-treated mice significantly compared to that in mice that received BaP alone. While dysplasia of varying degrees was noted in colon of BaP-treated mice, the dysplasias were of limited occurrence in RVT-treated mice. To ascertain whether the tumor inhibition is a result of altered BaP-induced toxicity of tumor cells, growth, apoptosis and proliferation of adenocarcinoma cells were assessed posttreatment with RVT and BaP. Cotreatment with RVT increased apoptosis and decreased cell proliferation to a greater extent than with BaP alone. Overall, our observations reveal that RVT inhibits colon tumorigenesis when given together with BaP and holds promise as a therapeutic agent.  相似文献   
33.
OBJECTIVE--To test whether a fat reduced diet rich in soluble dietary fibre, antioxidant vitamins, and minerals reduces complications and mortality after acute myocardial infarction. DESIGN--Randomised, single blind, controlled trial. SETTING--Primary and secondary care research centre for patients with myocardial infarction. SUBJECTS--505 patients with suspected acute myocardial infarction. Those with definite or possible acute myocardial infarction and unstable angina based on World Health Organisation criteria were assigned to diet A (n = 204) or diet B (n = 202) within 24-48 hours of infarction. INTERVENTIONS--Both groups were advised to follow a fat reduced diet. Group A was also advised to eat more fruit, vegetables, nuts, and grain products. MAIN OUTCOME MEASURES--Mortality from cardiac disease and other causes. Serum lipid concentrations and compliance with diet. RESULTS--Blood lipoprotein concentrations and body weight fell significantly in patients in group A compared with those in group B (cholesterol fell by 0.74 mmol/l in group A v 0.32 mmol/l in group B, 95% confidence interval of difference 0.14 to 0.70, and weight by 7.1 v 3.0 kg, 0.52 to 7.68). The incidence of cardiac events was significantly lower in group A than group B (50 v 82 patients, p less than 0.001). Group A also had lower total mortality (21 v 38 died, p less than 0.01) than group B. CONCLUSIONS--Comprehensive dietary changes in conjunction with weight loss immediately after acute myocardial infarction may modulate blood lipoproteins and significantly reduce complications and mortality after one year.  相似文献   
34.
Mycobacterium tuberculosis (Mtb) virulence is decreased by genetic deletion of the lipoprotein LprG, but the function of LprG remains unclear. We report that LprG expressed in Mtb binds to lipoglycans, such as lipoarabinomannan (LAM), that mediate Mtb immune evasion. Lipoglycan binding to LprG was dependent on both insertion of lipoglycan acyl chains into a hydrophobic pocket on LprG and a novel contribution of lipoglycan polysaccharide components outside of this pocket. An lprG null mutant (Mtb ΔlprG) had lower levels of surface-exposed LAM, revealing a novel role for LprG in determining the distribution of components in the Mtb cell envelope. Furthermore, this mutant failed to inhibit phagosome-lysosome fusion, an immune evasion strategy mediated by LAM. We propose that LprG binding to LAM facilitates its transfer from the plasma membrane into the cell envelope, increasing surface-exposed LAM, enhancing cell envelope integrity, allowing inhibition of phagosome-lysosome fusion and enhancing Mtb survival in macrophages.  相似文献   
35.
Our purposes were to 1) develop an animal model where intravenously (iv) administered d-glucose consistently inhibited antral motility, and 2) use this model to assess whether iv glucose acts to inhibit motility from a peripheral or a central nervous system site and to elucidate the factor(s) that determine(s) whether stomach motor function is sensitive to changes in blood glucose. Rats were anesthetized with alpha-chloralose-urethane, and antral motility was measured by a strain-gauge force transducer sutured to the antrum. In some cases, antral motility and gastric tone were measured by monitoring intragastric balloon pressure. Increases in blood glucose were produced by continuous iv infusion of 25% d-glucose at 2 ml/h. Inhibition of antral motility and gastric tone was observed when gastric contractions were induced by hypoglycemia (subcutaneously administered insulin, 2.5 IU/animal). In contrast, no inhibition of gastric motor function was observed when glucose infusion was tested on gastric contractions that were 1) spontaneously occurring, 2) evoked by iv administered bethanechol in vagotomized animals, and 3) evoked by the TRH analog RX77368, microinjected into the dorsal motor nucleus of the vagus. Using the model of insulin-induced hypoglycemia to increase gastric motor activity, we found that neither sectioning the hepatic branch of the vagus (n = 5), nor treating animals with capsaicin to destroy sensory vagal afferent nerves (n = 5) affected the ability of iv d-glucose to inhibit gastric motor function. Our results indicate that an important factor determining whether stomach motor function will be sensitive to changes in blood glucose is the method used to stimulate gastric contractions, and that the primary site of the inhibitory action of iv glucose on gastric motility is the central nervous system rather than the periphery.  相似文献   
36.
Toxicity induced by heavy metals deteriorates soil fertility status. It also adversely affects the growth and yield of crops. These heavy metals become part of the food chain when crops are cultivated in areas where heavy metals are beyond threshold limits. Cadmium (Cd) and nickel (Ni) are considered the most notorious ones among different heavy metals. The high water solubility of Cd made it a potential toxin for plants and their consumers. Accumulation of Ni in plants, leaves, and fruits also deteriorates their quality and causes cancer in humans when such a Ni-contaminated diet is used regularly. Both Cd and Ni also compete with essential nutrients of plants, making the fertility status of soil poor. To overcome this problem, the use of activated carbon biochar can play a milestone role. In the recent past application of activated carbon biochar is gaining more and more attention. Biochar sorb the Cd and Ni and releases essential micronutrients that are part of its structure. Many micropores and high cation exchange capacity make it the most acceptable organic amendment to improve soil fertility and immobilize Cd and Ni. In addition to improving water and nutrients, soil better microbial proliferation enhances the soil rhizosphere ecosystem and nutrient cycling. This review has covered Cd and Ni harmful effects on crop yield and their immobilization by activated carbon biochar. The focus was made to elaborate on the positive effects of biochar on crop yield and soil health.  相似文献   
37.
Main objective of the study was to record the ethnobotanical uses of indigenous plants of the federally administered tribal area (FATA), Bhittani (Local Tribe). Total interviewed local informants of different ages through questionnaire were 212 (196 male and 16 female). Well-known statistical indices, Use Value (UVi) formula and Fidelity Level (FL%) were used for quantification of the recorded data. After identification, the collected specimens were deposited in the Herbarium of Botany Department, Pir Mehr Ali Shah Arid Agriculture University, Rawalpindi, Pakistan. Present findings reveal that 38 plants species belonging to 26 families were being used in the treatment of 31 different diseases. Regarding plant habit, herbs were the leading growth form (63%), followed by trees (24%) and shrubs (13%) respectively. Solanaceae (13.16%) was leading family used in curing various diseases, followed by Asteraceae and Moraceae (7.89% each). Most cited families by the informants were Solanaceae (5 species, 137 citations), Asteraceae (3 species, 81 citations), Moraceae (3 species, 69 citations) and Amaryllidaceae (2 species, 57 citations). Most of taxa were used in curing constipation and stomach problem (9.88% each), followed by pain and cough (7.41% each), digestive and fever (4.96% each). Most frequently used plant part for curing different diseases was leaves (33.33%), followed by fruits (21.67%) and roots (13.33%). Medicinal plants with most use values and high ranks were Withania coagulans (0.88) ranked 1st and Cichorium intybus 2nd (0.81) while Cichorium intybus also showed 100% FL value. Plants of study area provide most of the basic requirements for the survival of local communities. There is huge pressure exerted on the natural vegetation due to their overuse by the inhabitants of the area. If proper remedial measures are not taken soon, this process may lead to decline of the valuable plant species from the study area.  相似文献   
38.
Zhang  Qingmeng  Ahmed  Niaz  Gao  George F.  Zhang  Fengmin 《中国病毒学》2020,35(6):868-874
In this article, we systematically review Dr. Wu Lien-Teh's academic achievements and outstanding contributions in the prevention and control of the plague epidemic in northeast China and introduce the development of the earliest public health epidemic prevention system in China in order to commemorate the 140th anniversary of Dr. Wu Lien-Teh's birth. We hope that this article will provide insights into the effective prevention and control of emerging infectious diseases as well as the current worldwide pandemic of COVID-19, facilitating the improvement and development of public health systems in China and around the globe.  相似文献   
39.
Two chlorodiorganotin(IV) complexes of 4-(2-methoxyphenyl)piperazine-1-carbodithioate (MPPDA) have been synthesized by 1:1 mole-ratio reactions of the parent acid (MPPDAH) with Me2SnCl2 or Et2SnCl2 in dry methanol. The products have been characterized by Raman and multinuclear NMR (1H, 13C and 119Sn) spectroscopy, elemental analysis, and mass spectrometry. Single-crystal X-ray diffraction studies indicate that both complexes have distorted trigonal bipyramidal geometries around the central Sn atom.  相似文献   
40.
Soil amendment with two types of composts: animal manure (AC) and vegetable waste (VC) induced composts have potential to alleviate Cd toxicity to maize in contaminated soil. Therefore, Cd mobility in waste water irrigated soil can be addressed through eco-friendly and cost effective organic soil amendments AC and VC that eventually reduces its translocation from polluted soil to maize plant tissues. The comparative effectiveness of AC and VC at 3% rate were evaluated on Cd solubility, its accumulation in maize tissues, translocation from root to shoot, chlorophyll contents, plant biomass, yield and soil properties (pH, NPK, OM). Results revealed that the addition of organic soil amendments significantly minimized Cd mobility and leachability in soil by 58.6% and 47%, respectively in VC-amended soil over control. While, the reduction was observed by 61.7% and 57%, respectively when AC was added at 3% over control. Comparing the control soil, Cd uptake effectively reduced via plants shoots and roots by 50%, 46% respectively when VC was added in polluted soil. However, Cd uptake was decreased in maize shoot and roots by 58% and 52.4% in AC amended soil at 3% rate, respectively. Additionally, NPK contents were significantly improved in polluted soil as well as in plant tissues in both composts amended soil Comparative to control, the addition of composts significantly improved the maize dry biomass and chlorophyll contents at 3% rate. Thus, present study confirmed that the addition of animal manure derived compost (AC) at 3% rate performed well and might be consider the suitable approach relative to vegetable compost for maize growth in polluted soil.  相似文献   
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