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51.
Increased cyanobacterial blooms, a source of cyanotoxins are linked with climate change and eutrophication in aquatic bodies, a major concern worldwide. Microcystins are potently hepatotoxic, nephrotoxic as well as carcinogenic. Thus microcystins are threat to tourism, agriculture and animal's health. However, there is a still lacuna in the knowledge of regulation of microcystins production. Presence of toxic and non-toxic cyanobacterial strains together and occurrence of various microcystin variants in aquatic bodies compounded the problem. Although several analytical techniques for microcystin detection such as bioassay, ELISA, HPLC and LC-MS etc. have been already prevalent, the development of biosensors offered rapid and accurate detection, high reproducibility and portability. Sequencing of Microcystis spp., opened the new vistas towards the development of biosensor at molecular and genetic level. This review incorporates the current trends in the development of biosensors for microcystin detection in the light of state-of-the-art techniques.  相似文献   
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BACKGROUND: Although dietary carbohydrates are thought to play a role in cataractogenesis, few epidemiologic studies have examined links between carbohydrate nutrition and cataract. OBJECTIVES: We investigated the associations between dietary glycemic index (GI), glycemic load (GL), total carbohydrate intake, and 10-y incident nuclear, cortical, and posterior subcapsular cataract. DESIGN: Of 3654 baseline participants in an Australian population aged >/=49 y (1992-1994), 933 were seen after 5 and/or 10 y, had completed a detailed semiquantitative food-frequency questionnaire, had no previous cataract surgery or baseline cataract, and had photographs taken to assess incident cataract with the Wisconsin Cataract Grading System. Dietary information was collected with a validated food questionnaire. GI was calculated from a customized database of Australian foods. GI, GL, and all other nutrients were energy adjusted. Hazard ratios (HRs) and 95% CIs were calculated with the use of discrete logistic models. RESULTS: After age, sex, diabetes, and other factors were controlled for, each SD increase in GI significantly predicted incident cortical cataract (HR: 1.19; 95% CI: 1.01, 1.39). Participants within the highest compared with the lowest quartile of GI were more likely to develop incident cortical cataract (HR: 1.77; 95% CI: 1.13, 2.78; P for trend = 0.035). These findings were similar after excluding participants with diabetes, although they were slightly attenuated and marginally nonsignificant (HR: 1.16; 95% CI: 0.98, 1.37, per SD increase in GI). No association was found between GI and nuclear or posterior subcapsular cataract and between GL or carbohydrate quantity and any cataract subtype. CONCLUSION: In an Australian cohort, poorer dietary carbohydrate quality, reflected by high GI, predicted incident cortical cataract.  相似文献   
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Diabetes is often accompanied by lipid abnormalities, which contribute significantly to cardiovascular morbidity and mortality in diabetic patients. Previously, we have demonstrated potent hypoglycemic activity of lyophilized aqueous extract of Murraya koenigii leaves in normal and alloxan induced diabetic rabbits for short duration of 6 h. In this study, we examined the effect of 1 month oral administration of Murraya koenigii aqueous leaves extract in normal and STZ induced severe diabetic rats, at the dose of 300 mg/kg bw, on various biochemical parameters, viz., fasting blood glucose (FBG), total cholesterol (TC), HDL-cholesterol (HDL), triglyceride (TG), alkaline phosphatase (ALKP), serum glutamate oxaloacetate and pyruvate transaminases (SGOT and SGPT) and serum creatinine. In case of diabetic animals fasting blood glucose (FBG) levels of treated animals reduced by 48.2% after 30 days treatment with the aqueous leaves extract. A fall of 19.2 and 30.8% in TC and 22.97 and 37.1% in TG levels were also observed in the case of treated normal as well as diabetic rats, respectively. Feeding the extract increased the HDL-cholesterol level by 16 and 29.4% in normal and diabetic rats, respectively, as compared with their initial values. In the normal rats after 1 month of oral administration of the extract SGOT and SGPT levels were decreased by 21.7 and 25.0%. Serum alkaline phosphatase values of the treated normal animals were also reduced by 33% while negligible change was observed in the normal control animals. In the case of diabetic rats, SGOT and SGPT levels were reduced by 36.7 and 32.2%, respectively, whereas ALKP levels decreased by 39.7% after 1 month oral administration of the extract. The serum creatinine levels decrease in normal as well as in the diabetic animals by 17.75 and 18.2%, respectively, as compared to initial values. In the diabetic control animals the urinary sugar remains at +4 level but there was a decrease of 75% in urine sugar in the case of treated diabetic rats. This indicates that the aqueous extract of Murraya koenigii has favorable effect in bringing down the severity of diabetes.  相似文献   
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Broccoli is a popular Brassica vegetable widely consumed worldwide for its superior nutritive value and delicious taste. It is also a rich source of several health beneficial phytochemicals. However, sudden fluctuation in temperature, especially in tropical countries spoils the broccoli crop by distorting the heads and puts immense pressure on the farmers by virtue of monetary losses. Usually the broccoli curd is consumed, and the stalk is thrown away which is also of considerable nutritive value. In the present study, the antioxidant potential of the stalk was investigated and it was found to be a rich source of ascorbic acid, carotene and phenols. It is therefore, concluded that the broccoli stalk would provide a suitable means to add nutritive value to the diet in form of salad dressings, in combination with soups, pastas, fries etc. The optimal utilization of the stalk would provide immense nutritive and health benefits, curb malnutrition, supplement diet with phytochemicals and would also provide monetary benefits to the farmers from the sale of even the spoiled broccoli crops.  相似文献   
55.
We performed dynamic linear modeling analysis on fish contaminant data collected from the Ontario Ministry of the Environment and Environment Canada to examine long-term trends of total mercury (THg) and polychlorinated biphenyls (PCBs) in Lake Erie. Several sport fish species (walleye, smallmouth bass, rainbow trout) with differences in their diet habits, food competition strategies and foraging patterns are characterized by weakly increasing trends of their THg levels in Lake Erie after the mid- or late 1990s. Similarly, our analysis shows that the decline rates of the PCB body burdens in white bass, smallmouth bass, freshwater drum and whitefish have slowed down or have switched to weakly increasing rates over the last decade. Our analysis also provides evidence that the rainbow trout and coho salmon PCB concentrations have been decreasing steadily but the associated rates were fairly weak. The systematic shifts in energy trophodynamics along with the food web alterations induced from the introduction of non-native species, the new role of the sediments as a net contaminant source, and the potentially significant fluxes from the atmosphere stand out as some of the hypotheses proposed to explain the limited Lake Erie response in recent years to the various contamination mitigation strategies.  相似文献   
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Surfactant protein A (SP-A) binds to and modulates phagocytosis of Mycobacterium tuberculosis by macrophages. We investigated the relationship between polymorphisms in the collagen regions of SP-A1 and SP-A2 genes and pulmonary tuberculosis. In the present study, seven single nucleotide polymorphisms (SNPs) (4 exonic and 3 intronic) have been identified in the collagen regions of SP-A1 and SP-A2 genes in Indian population. Two intronic polymorphisms, SP-A1C1416T ((p = 0.0000, odds ratio (OR) = 20.767,95% CI: 8.315-OR<51.870) and SP-A2C1382G (p = 0.0054; OR = 3.675, 95% CI: 1.400< OR<9.644), showed significant association with pulmonary tuberculosis (number of patients = 10, number of controls = 7). A redundant SNPA1660G of SP-A2gene showed significant association with pulmonary tuberculosis (number of patients = 17, number of controls = 19, p = 0.0000, OR = 8.94,95% CI: 3.311相似文献   
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PurposeIn 2011, we introduced an innovative parallel curriculum at Baylor College of Medicine, formerly called the Genetics Track Curriculum and now called the Genetics and Genomics Pathway, aimed at providing an opportunity for an enriched educational experience throughout medical school. In this report, we describe our 10-year experience with the program and highlight growth in enrollment as well as academic achievements of graduating students.MethodsWe reviewed the data of students enrolled in this pathway, including retention, satisfaction, student-driven curriculum changes, scholarly outcomes, and career outcomes.ResultsFrom September 2011 to June 2021, 121 students were enrolled in the Genetics and Genomics Pathway program. In total, 64 students (64/121 = 53%) left the program before graduating (the majority, after their first year). Of the 57 remaining students, 29 graduated (29/57, approximately 51%), and 4 of the 29 students (4/29 = 14%) matched into a genetics training program.ConclusionThis novel program serves as a mechanism for garnering increased interest and competence in medical genetics. The longitudinal nature of the program fosters enthusiasm for genetics and provides ample opportunity to develop valuable research skills. Given the ongoing shortage of providers in this field, such programs are vital to increase the size of the workforce and broaden the knowledge of providers in diverse fields.  相似文献   
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