Circadian rhythm and its role in malignancy

Circadian rhythms are daily oscillations of multiple biological processes directed by endogenous clocks. The circadian timing system comprises peripheral oscillators located in most tissues of the body and a central pacemaker located in the suprachiasmatic nucleus (SCN) of the hypothalamus. Circadian genes and the proteins produced by these genes constitute the molecular components of the circadian oscillator which form positive/negative feedback loops and generate circadian rhythms. The circadian regulation extends beyond clock genes to involve various clock-controlled genes (CCGs) including various cell cycle genes. Aberrant expression of circadian clock genes could have important consequences on the transactivation of downstream targets that control the cell cycle and on the ability of cells to undergo apoptosis. This may lead to genomic instability and accelerated cellular proliferation potentially promoting carcinogenesis. Different lines of evidence in mice and humans suggest that cancer may be a circadian-related disorder. The genetic or functional disruption of the molecular circadian clock has been found in various cancers including breast, ovarian, endometrial, prostate and hematological cancers. The acquisition of current data in circadian clock mechanism may help chronotherapy, which takes into consideration the biological time to improve treatments by devising new therapeutic approaches for treating circadian-related disorders, especially cancer.     

Quantitative assessment of metals in local brands of tea in Pakistan

In present study, Mn, Fe, Zn, Cu, Co, Pb, Cr, Ni and Cd were analyzed by FAAS in green and black tea samples of locally available in the Pakistani market. Na and K were also determined by Flame Photometer. Tea leaves can be the source of mineral components and trace elements, as well as some undesirable substances due to exposure to the environment. Among the metals tested, K was the most abundant one followed by Na, Mn and Fe. Fortunately, toxic heavy metals, Pb and Cd, had the lowest contents in tea samples and also in tea aqueous extracts. Concentration of heavy metals in tea aqueous extract was markedly lower than their total contents except that of K. The solubility of studied metals in tea aqueous extract varied widely and ranged from 0.0-95%. The lowest ranges of solubility were listed for toxic heavy metals Pb and Cd. The possible uptake of metals by the human body from tea aqueous extract has also been determined. The amounts of metals that one may take up through consumption of tea aqueous extract were found to match the acceptable daily intake even taking into account exposure from air, food and drinking water.     

Net primary productivity of Bruguiera parviflora (Wight & Arn.) dominated mangrove forest at Kuala Selangor,Malaysia

The net primary productivity of Bruguiera parviflora dominated mangrove forest at Kuala Selangor, Malaysia was estimated from the average yearly biomass increment and litter production. The average yearly biomass increment in saplings and trees was 0.58 and 16.51 t ha⁻¹, respectively, and the annual amount of total litter production was 10.35 t ha⁻¹. The biomass increment in saplings and trees was not significantly different (t-test, p > 0.05) in 2 successive years and the estimated net primary productivity was 27.44 t ha⁻¹ year⁻¹. The ratio (2.65:1) of net primary productivity and litterfall suggests that this mangrove forest is at a juvenile stage.     

Lipid Changes During Long-Term Storage of Canned Sprat

Lipid changes during canning and 3-years storage of oil and brine canned sprat were studied. Thermal treatment during precooking and sterilization produced an increase in free fatty acid content. Secondary oxidation product showed a considerable increase in canned samples after storage time. A significant increase was found by comparing the fluorescence shift measured in both canned samples with cooked fish. The fluorescence compound in both filling media was increased after 3 years. Oil canning affected the sprat fatty acids composition. Results showed the amount of saturated fatty acids (SFA), monounsaturated fatty acids (MUFA), and Σω3 significantly decreased in oil canned samples. However, the polyunsaturated fatty acids (PUFA) and Σω6 had the opposite behavior. The latter effect was more marked with increased storage time. Results showed the amount of SFA, MUFA, PUFA, and Σω3 did not alter in brine canned samples. After storage, the amount of MUFA and Σω3 decreased, and the content of SFA increased in brine canned samples.     

The effect of supplementing diets with extracts derived from three different species of macroalgae on growth,thermal stress resistance,antioxidant enzyme activities and skin colour of electric yellow cichlid (Labidochromis caeruleus)

The purpose of this study was to evaluate the growth, thermal stress resistance, antioxidant enzyme activities and skin colour of Labidochromis caeruleus (electric yellow cichlid) fed the diets supplemented with extracts derived from brown macroalga Sargassum boveanum, red macroalga Gracilaria persica and green macroalga Entromorpha intestinalis. One hundred and forty‐four fish were randomly distributed into 12 tanks and subjected to cold‐shock stress after 8 weeks of feeding the diets containing 1,000 mg extracts of macroalgae. Supplementation of fish diet with algal extracts led to improved growth performance (including higher final weight and weight gain) when compared to the control group, which was fed the non‐supplemented diet. The survival rate after cold‐shock stress was significantly higher in those fish fed the diets containing macroalgal extracts, especially E. intestinalis extract (75%). The superoxide dismutase activity in all dietary treatments was significantly lower than control, whereas no significant difference in the activities of catalase and lysozyme was observed among treatments. In addition, inclusion of macroalgal extracts in the diet resulted in higher a* (redness) and b* (yellowness) values compared to the control group. These results suggest that macroalgal extracts, especially E. intestinalis extract, can be used as feed additive for increasing antioxidants capacities as well as enhancing pigmentation in electric yellow cichlid.     

Coincidence of virulence shifts and population genetic changes of Pseudoperonospora cubensis in the Czech Republic

Pseudoperonospora cubensis is an oomycete pathogen causing downy mildew disease on a variety of Cucurbitaceae, and has recently re‐emerged as a destructive disease on crops in this family, mainly on cucumber and squash. Multilocus sequence analysis (MLSA) of four mitochondrial and two nuclear DNA regions was used to detect changes in the genetic structure of P. cubensis populations occurring in the Czech Republic that might be associated with recently reported shifts in virulence. The analysed sample set contains 67 P. cubensis isolates collected from 1995 to 2012 in the Czech Republic and some other European countries. Sequence analyses revealed differences and changes in the genetic backgrounds of P. cubensis isolates. While all isolates sampled before 2009 exhibited the genotype of the subspecies of Clade II and were collected from cucumber, all samples collected from other hosts belonged to Clade I (P. cubensis sensu stricto) or were sampled from 2009 onwards. In addition, 67·16% of all post‐2009 isolates from Clade II had two heterozygous positions in their nrITS sequence, which suggests sexual reproduction and/or a mutational origin. Thus, the results indicate that, apart from the rise in prevalence of Clade I, the change in the genetic structure of P. cubensis populations may be linked with a hybridization or, less likely, a mutation event that rendered strains able to infect a broader spectrum of host species.     

Wheat seed storage proteins: Advances in molecular genetics,diversity and breeding applications

Wheat seed storage proteins, especially glutenins and gliadins, have unique functional properties giving rise to a wide array of food products for human consumption. The wheat seed storage proteins, however, are also the most common cause of food-related allergies and intolerances, and it has become crucially important to understand their composition, variation and functional properties and interface this knowledge with the grain handling industry as well as the breeders. This review focuses on advances in understanding the genetics and function of storage proteins and their application in wheat breeding programs. These include: (1) The development and validation of high-throughput molecular marker systems for defining the composition and variation of low molecular weight glutenin subunits (LMW-GS) genes and a summary of the more than 30 gene-specific markers for rapid screening in wheat breeding programs; (2) The identification of more than 100 alleles of storage proteins in wild species provide candidate genes for future quality improvement; (3) The documentation of quality effects of individual LMW-GS and HMW-GS for improving end-use quality; and (4) The analysis of α-gliadin genes on chromosomes 6A and 6D with non-toxic epitopes as potential targets to develop less toxic cultivars for people with celiac disease. Genomic and proteomic technologies that will continue to provide new tools for understanding variation and function of seed storage proteins in wheat are discussed.