Analytical investigation of selected pesticide residues from fruits and vegetables by an improved extraction method using reverse phase High Performance Liquid Chromatograph

Pesticide residues like chlorpyrifos, cypermethrin, deltamethrin and dichlorvos were monitored by an improved extraction method from apple, peach and potato using reverse phase high performance liquid chromatography. The selected pesticides were extracted from fruits and vegetable samples using smaller volume of ethyl-acetate, anhydrous sodium sulphate, and sodium chloride. Cleanup of extract was done with activated charcoal. Final extracts of fruits and vegetable samples were analysed using reverse phase high performance liquid chromatography with a ultra-violet detector in an isocratic mode. Maximum residue levels (MRL), 0.924, 1.630 and 0.454 μg/g for chlorpyrifos, cypermethrin and deltamethrin were found in peach respectively. The MRL 0.283 μg/g for dichlorvos was found in apple samples. All these observed results were compared with Codex maximum residue levels. It was found that cypermethrin and chlorpyrifos residual amounts were greater than MRLs, so their spray on the target crops should be limited because these are resistant to the degradation.Keywords: Pesticide residues, reverse phase High Performance Liquid Chromatography, chlorpyrifos, cypermethrin, deltamethrin, dichlorvo

Production of lignin peroxidase by Ganoderma leucidum using solid state fermentation

The main objectives of this study were to optimize the culture conditions for the production of lignin peroxidase by Ganoderma leucidum, economic utilization of waste corn cobs as inducers substrate by pollution free fermentation technology and to optimize the solid state fermentation (SSF) process for lignin peroxidase (LiP) production. Growth medium employed for the culture of G. leucidum for the production of LiP was supplied with fermentation conditions that were optimized before selection like incubation period, inoculum size, temperature, pH, substrate to water ratio, nitrogen source, yeast extract and cane molasses. Culture was harvested on the fourth day and diluted five times with distilled water and filtrate was stored in Eppendoff tubes for enzyme assay using 310 nm wave lengths in the spectrophotometer. Lignin peroxidase production was enhanced and maximum LiP activity (2807 U/ml) was found in the growth medium after 96 h, inoculum size 3 ml, pH 4.5 and temperature 35°C with substrate to water ratio of 20 ml/5 g, yeast extract 4%, (NH4)2SO4, 2% and cane molasses 3%. Results indicate the excellent scope of corn cobs as solid state substrate for the production of lignin peroxidase by G. leucidum.Key words: Lignin peroxidase (LiP), Ganoderma leucidum, fermentation, corn cobs, cane molasses

Utilisation of an operative difficulty grading scale for laparoscopic cholecystectomy

Background A reliable system for grading operative difficulty of laparoscopic cholecystectomy would standardise description of findings and reporting of outcomes. The aim of this study was to validate a difficulty grading system (Nassar scale), testing its applicability and consistency in two large prospective datasets. Methods Patient and disease-related variables and 30-day outcomes were identified in two prospective cholecystectomy databases: the multi-centre prospective cohort of 8820 patients from the recent CholeS Study and the single-surgeon series containing 4089 patients. Operative data and patient outcomes were correlated with Nassar operative difficultly scale, using Kendall’s tau for dichotomous variables, or Jonckheere–Terpstra tests for continuous variables. A ROC curve analysis was performed, to quantify the predictive accuracy of the scale for each outcome, with continuous outcomes dichotomised, prior to analysis. Results A higher operative difficulty grade was consistently associated with worse outcomes for the patients in both the reference and CholeS cohorts. The median length of stay increased from 0 to 4 days, and the 30-day complication rate from 7.6 to 24.4% as the difficulty grade increased from 1 to 4/5 (both p < 0.001). In the CholeS cohort, a higher difficulty grade was found to be most strongly associated with conversion to open and 30-day mortality (AUROC = 0.903, 0.822, respectively). On multivariable analysis, the Nassar operative difficultly scale was found to be a significant independent predictor of operative duration, conversion to open surgery, 30-day complications and 30-day reintervention (all p < 0.001). Conclusion We have shown that an operative difficulty scale can standardise the description of operative findings by multiple grades of surgeons to facilitate audit, training assessment and research. It provides a tool for reporting operative findings, disease severity and technical difficulty and can be utilised in future research to reliably compare outcomes according to case mix and intra-operative difficulty

The Role of Neighborhood Environment in Promoting Risk Factors of Cardiovascular Disease among Young Adults: Data from Middle to High Income Population in an Asian Megacity

Background: Modifiable risk factors of cardiovascular diseases (CVD) have their triggers in the neighborhood environments of communities. Studying the environmental triggers for CVD risk factors is important to understand the situation in a broader perspective. Young adults are influenced the most by the environment profile around them hence it is important to study this subset of the population.Methods: This was a descriptive study conducted using the EPOCH research tool designed by the authors of the PURE study. The study population consisted of young adults aged 18-25 in two areas of Karachi. The study setting was busy shopping malls frequented by young adults in the particular community being studied.Results: Our total sample size was 120 individuals, who consented to be interviewed by our interviewers. Less than 50% of the population recognized some form of restriction regarding smoking in their communities. The largest contributor to tobacco advertising was actors smoking in movies and TV shows with 89% responses from both communities. Only 11.9% of the individuals disapproved of smoking cigarettes among men with wide acceptance of \u27sheesha\u27 across all age groups. Advertising for smoking and junk food was more frequent as compared to smoking cessation, healthy diet and exercise in both the areas. Unhealthy food items were more easily available in contrast to healthier options. The cost of healthy snack food options including vegetables and fruits was higher than sugary drinks and foods.CONCLUSION: This assessment showed that both communities were exposed to environments that promote risk factors for cardiovascular diseases

Photoactivatable drugs for nicotinic optopharmacology

Photoactivatable pharmacological agents have revolutionized neuroscience, but the palette of available compounds is limited. We describe a general method for caging tertiary amines by using a stable quaternary ammonium linkage that elicits a red shift in the activation wavelength. We prepared a photoactivatable nicotine (PA-Nic), uncageable via one- or two-photon excitation, that is useful to study nicotinic acetylcholine receptors (nAChRs) in different experimental preparations and spatiotemporal scales

Dynamic Gene Expression in the Human Cerebral Cortex Distinguishes Children from Adults

In comparison with other primate species, humans have an extended juvenile period during which the brain is more plastic. In the current study we sought to examine gene expression in the cerebral cortex during development in the context of this adaptive plasticity. We introduce an approach designed to discriminate genes with variable as opposed to uniform patterns of gene expression and found that greater inter-individual variance is observed among children than among adults. For the 337 transcripts that show this pattern, we found a significant overrepresentation of genes annotated to the immune system process (pFDR≅0). Moreover, genes known to be important in neuronal function, such as brain-derived neurotrophic factor (BDNF), are included among the genes more variably expressed in childhood. We propose that the developmental period of heightened childhood neuronal plasticity is characterized by more dynamic patterns of gene expression in the cerebral cortex compared to adulthood when the brain is less plastic. That an overabundance of these genes are annotated to the immune system suggests that the functions of these genes can be thought of not only in the context of antigen processing and presentation, but also in the context of nervous system development