Shelf-life of smoked eel fillets treated with chitosan or thyme oil

The present study examined the effect of natural antimicrobials: Chitosan, thyme oil and their combination, on the shelf- life of smoked eel fillets stored under vacuum packaging (VP) at 4°C. Based on sensory odor data smoked eel fillets had a shelf- life of 35 (control), 42 (thyme treated and >49 (thyme, chitosan-thyme treated) days. The thiobarbituric acid value (TBA) value of the control eel sample was significantly higher than the chitosan-thyme-treated eel samples. The use of chitosan singly, or in combination with thyme oil reduced lipid oxidation (TBA) of the smoked eel samples. A trimethylamine nitrogen (TMA-N) value of 10 mg N/100 g, could be suggested as an indication of smoked eel spoilage initiation. Control and treated eel reached total volatile basic nitrogen (TVB-N) values of 13.1-31.5 mg N/100 g below the maximum permissible level of TVB-N in fish and fishery products. Eel samples reached the value of 7.0 log cfu/g (Total Plate Count,TPC) on days 35 (smoked) and 42 (thyme treated), whereas both chitosan and chitosan-thyme treated eel samples never reached this limit value. Results of our study show thyme or chitosan (singly, or in combination) inhibit the growth of mesophilic bacteria and extend the shelf- life of smoked eel.Deanship of Scientific Research at King Saud Universit

Bisphenol A Detection in Various Brands of Drinking Bottled Water in Riyadh, Saudi Arabia Using Gas Chromatography/Mass Spectrometer

Purpose: To assess whether bisphenol A contamination occurred in seven brands of bottled drinking water in Riyadh, Saudi Arabia.Methods: Liquid-liquid extraction (using dichloromethane) was used to analytically extract bisphenol A from drinking water bottles and a gas chromatograph-mass spectrometer was employed for its detection using a splitless capillary column and helium as the carrier gas.Results: The concentration of bisphenol A (BPA) was high in all the bottled water brands tested. The mean concentration of BPA of the bottled water stored indoors (4.03 ng/L) was significantly lower than that stored outdoors (7.5 ng/L).Conclusion: Our results show that significant amounts of BPA leached from bottle containers into the water. Long storage of bottled water under direct sunlight should be avoided to reduce the risk of human exposure to BPA

Histopathological Effects on Testis of Adult Male Carp, Cyprinus carpio carpio, Following Exposure to Graded Concentrations of Water-Borne Bisphenol A

Purpose: To evaluate the estrogenic effect of Bisphenol A (BPA), an endocrine disruptor on the histological features in carp testisMethods: Adult male fish, koi carp, Cyprinus carpio carpio, were exposed to three graded concentrations of BPA (10, 100 and 1000 μg/L) for a period of 21 days. A single dose of 17-β estradiol (1 ng/L) was used as positive control. The end points assessed at the end of the exposure period were condition factor, hepatosomatic index (HSI), gonadosomatic index (GSI), histopathological changes in the testis and lobular diameter.Results: BPA caused a significant decrease in gonadosomatic index (GSI) of the fish at the median concentration of 100 μg/L. The major alterations observed in the gonad structure were a significant decrease (p ≤ 0.001) in the lobular diameter (65.1 ± 12.2 μm) compared with control (211.7 ± 36.60 μm) and complete loss in lobular structure with degenerating spermatozoa in some carps. The histopathological effects also include delayed sperm maturation and impaired spermatogenesis.Conclusion: The findings clearly show marked adverse histopathological effects of gonads of adult carps when exposed to BPA.Keywords: Fish, Carp testis, Endocrine disruptors, Bisphenol A, Histopathology, Gonadosomatic index, Sperm maturation, Spermatogenesi

Preparation, characterization and antibacterial effects of eco-friendly gold nanorods

Purpose: To synthesize and characterize eco-friendly gold nanorods (Au-NRs) and to assess their effects against two bacterial strains.Methods: Synthesis of eco-friendly gold nanorods was done from an aqueous solution of chloroauric acid and cetyltrimethylammonium bromide by mixing Olea europaea fruit and Acacia nilotica husk extracts with the latter as a reducing agent. The synthesis was monitored by ultraviolet–visible (UV) spectrophotmetry and a zetasizer, while the morphology of the resulting nanorods was assessed by transmission electron microscopy (TEM) and scanning electron microscopy (SEM) coupled with an energy-dispersive spectrophotometer (EDS). The effect of the prepared eco-nanorods on growth of Escherichia coli and Staphylococcus aureus bacteria were investigated by agar diffusion method.Results: The synthesized Au-NRs were mostly rod-shaped, with mean size of 96 nm. They exhibited a potent antibacterial activity against Gram-positive and  Gram-negative microorganisms (Escherichia coli and Staphylococcus aureus).Conclusion: The findings suggest that the nanoformulation of the biomaterial mix of Olea europaea fruit and Acacia nilotica husk extracts is a cost-effective, eco-friendly, and non-toxic synthesis of Au- NRs which has therpeautic potential.Keywords: Olea europaea, Acacia nilotica, Gold nanorods, Eco-friendly synthesis, Gram-positive and Gram-negative microorganism

Methodological problem with comparing increases in different measures of body weight

<p>Abstract</p> <p>Background</p> <p>A number of studies have compared proportional increases over time in waist circumference (WC) and body mass index (BMI). However this method is flawed. Here, we explain why comparisons of WC and BMI must take into account the relationship between them. We used data from two cross-sectional US surveys (NHANES 1988-94 and 2005-06), and calculated the percentage change in the average BMI and the average WC between the two surveys, comparing the results with a regression analysis of changes in WC relative to BMI.</p> <p>Findings</p> <p>The crude percentage change in BMI (5.8%) was marginally greater than for WC (5.1%). But these percentages cannot be directly compared, as the relationship between the measures is described by a regression equation with an intercept term that does not equal zero. The coefficient of time from the regression equation will determine whether or not WC is on average larger for a given BMI at the second compared with the first time point.</p> <p>Conclusion</p> <p>Differences in the percentage change in WC and the percentage change in BMI cannot be usefully directly compared. Comparisons of increases in the two measures must account for the relationship between them as described by the regression equation.</p

Endocrine Disruptors and Obesity: An Examination of Selected Persistent Organic Pollutants in the NHANES 1999–2002 Data

Recent evidence suggests that endocrine disrupting chemicals (EDCs) may cause perturbations in endogenous hormonal regulation that predispose to weight gain. Using data from NHANES (1999–2002), we investigated the association between body mass index (BMI), waist circumference (WC) and selected persistent organic pollutants (POPs) via multiple linear regressions. Consistent interaction was found between gender, ln oxychlordane and ln p,p’ DDT. Also, we found an association between WC and ln oxychlordane and ln hpcdd in subjects with detectable levels of POPs, whereas an association between WC and ln p,p’ DDT was observed in all subjects. Furthermore, ln Ocdd showed an increase with higher WC and BMI, whereas, ln trans-nonachlor decreased with higher BMI. Hence, BMI and WC are associated with POPs levels, making the chemicals plausible contributors to the obesity epidemic

An Examination of the Association of Selected Toxic Metals with Total and Central Obesity Indices: NHANES 99-02

It is conceivable that toxic metals contribute to obesity by influencing various aspects of metabolism, such as by substituting for essential micronutrients and vital metals, or by inducing oxidative stress. Deficiency of the essential metal zinc decreases adiposity in humans and rodent models, whereas deficiencies of chromium, copper, iron, and magnesium increases adiposity. This study utilized the NHANES 99-02 data to explore the association between waist circumference and body mass index with the body burdens of selected toxic metals (barium, cadmium, cobalt, cesium, molybdenum, lead, antimony, thallium, and tungsten). Some of the associations were significant direct relationships (barium and thallium), and some of the associations were significant inverse relationships (cadmium, cobalt, cesium, and lead). Molybdenum, antimony, and tungsten had mostly insignificant associations with waist circumference and body mass index. This is novel result for most of the toxic metals studied, and a surprising result for lead because high stored lead levels have been shown to correlate with higher rates of diabetes, and obesity may be a key risk factor for developing diabetes. These associations suggest the possibility that environmental exposure to metals may contribute to variations in human weight gain/loss. Future research, such as prospective studies rather than the cross-sectional studies presented here, is warranted to confirm these findings

FAPRI 2002 World Agricultural Outlook

Crop Production/Industries, Livestock Production/Industries,

Hyperphosphorylated tau in young and middle-aged subjects

The brain tissue obtained from ninety-five cognitively unimpaired subjects, with ages ranging from 22 to 50 years upon death, were immunohistochemically assessed for neurodegenerative changes, i.e., hyperphosphorylated tau (HPτ) and β-amyloid (Aβ) pathology in predilection neuroanatomical areas. HPτ pathology was observed in the transentorhinal cortex and/or the locus coeruleus (LC) in 33% of the subjects, without any obvious risk factors known to alter the microtubule-associated protein. HPτ pathology was noted in the LC in 25 out of 83 subjects (30%), lacking concomitant cortical Aβ or transentorhinal HPτ pathology. This observation was present even when assessing only one routine section of 7 μm thickness. The recent suggestion of prion-like propagation of neurodegeneration and the finding of neurodegeneration being quite common in middle-aged persons is alarming. It is noteworthy, however, that a substantial number of neurologically unimpaired subjects even at a very old age display only sparse to modest extent of neurodegenerative pathology. Thus, only a subset of subjects with neurodegenerative changes early in life seem to progress to a symptomatic disease with ageing. This observation brings forth the notion that other, yet unknown modifying factors influence the progression of degeneration that leads to a symptomatic disorder. The known association between alterations in the LC and mood disorders, and the finding of the LC being frequently affected with HPτ pathology suggest that clinicopathological studies on young subjects both with or without mood disorders are warranted

Imputation strategies for missing binary outcomes in cluster randomized trials

<p>Abstract</p> <p>Background</p> <p>Attrition, which leads to missing data, is a common problem in cluster randomized trials (CRTs), where groups of patients rather than individuals are randomized. Standard multiple imputation (MI) strategies may not be appropriate to impute missing data from CRTs since they assume independent data. In this paper, under the assumption of missing completely at random and covariate dependent missing, we compared six MI strategies which account for the intra-cluster correlation for missing binary outcomes in CRTs with the standard imputation strategies and complete case analysis approach using a simulation study.</p> <p>Method</p> <p>We considered three within-cluster and three across-cluster MI strategies for missing binary outcomes in CRTs. The three within-cluster MI strategies are logistic regression method, propensity score method, and Markov chain Monte Carlo (MCMC) method, which apply standard MI strategies within each cluster. The three across-cluster MI strategies are propensity score method, random-effects (RE) logistic regression approach, and logistic regression with cluster as a fixed effect. Based on the community hypertension assessment trial (CHAT) which has complete data, we designed a simulation study to investigate the performance of above MI strategies.</p> <p>Results</p> <p>The estimated treatment effect and its 95% confidence interval (CI) from generalized estimating equations (GEE) model based on the CHAT complete dataset are 1.14 (0.76 1.70). When 30% of binary outcome are missing completely at random, a simulation study shows that the estimated treatment effects and the corresponding 95% CIs from GEE model are 1.15 (0.76 1.75) if complete case analysis is used, 1.12 (0.72 1.73) if within-cluster MCMC method is used, 1.21 (0.80 1.81) if across-cluster RE logistic regression is used, and 1.16 (0.82 1.64) if standard logistic regression which does not account for clustering is used.</p> <p>Conclusion</p> <p>When the percentage of missing data is low or intra-cluster correlation coefficient is small, different approaches for handling missing binary outcome data generate quite similar results. When the percentage of missing data is large, standard MI strategies, which do not take into account the intra-cluster correlation, underestimate the variance of the treatment effect. Within-cluster and across-cluster MI strategies (except for random-effects logistic regression MI strategy), which take the intra-cluster correlation into account, seem to be more appropriate to handle the missing outcome from CRTs. Under the same imputation strategy and percentage of missingness, the estimates of the treatment effect from GEE and RE logistic regression models are similar.</p