Changes in expression of neuropeptides and their receptors in the hypothalamus and gastrointestinal tract of calorie restricted hens

The list of orexigenic and anorexigenic peptides, those are known to alter feed intake, is continuously growing. However, most of them are studied in mammalian species. We aimed to investigate plasma level and mRNA expression of the pituitary adenylate cyclase-activating polypeptide (PACAP), gene expression of its receptor (PAC1), furthermore the gene expression of galanin (GAL), neuromedin U (NMU), and its two receptors (NMUR1 and NMUR2) in the hypothalamus, proventriculus, and jejunum of hens exposed to 40% calorie restriction. Feed restriction resulted in a 88% increase in mRNA and a 27% increase in peptide level of PACAP in proventriculus measured with qPCR and RIA, respectively. Increases were found in the gene expression of PAC1 (49%) and NMUR1 (63%) in the hypothalamus. Higher expressions of peptide encoding genes (76% for PACAP, 41% for NMU, 301% for NMUR1 and 308% for GAL, P < 0.05) were recorded in the jejunum of hens exposed to restricted nutrition. The results indicate that PACAP level responds to calorie restriction in the proventriculus and jejunum, but not in the hypothalamus and plasma

Extractability of polyphenols from black currant, red currant and gooseberry and their antioxidant activity

In this study, we analyzed extracts of Ribes (black currant, red currant and gooseberry) fruits obtained with methanol, methanol 50% and water. For each extract total polyphenol content, total flavonoid content and total anthocyanin content was assessed. The antioxidant activity of extracts was evaluated by 1,1-Diphenyl-2-picrylhydrazyl (DPPH) and 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) radical scavenging capacity and by the photo-chemiluminescence (PCL) method. Identification and quantification of individual phenolic compounds was performed by means of high performance liquid chromatograph coupled with diode array detector (HPLC-DAD) analyses. From each fruit, best extraction of polyphenols was obtained with methanol 50%. In case of red currants and gooseberry there was no significant difference in flavonoids and anthocyanins extraction rate by the different extraction solvents. For black currants the methanol and methanol 50% extract presented the highest antioxidant activity. For red currants extracts with methanol 50% showed stronger antioxidant activity (IC50 = 5.71 mg/ml for DPPH, IC50 = 1.17 mg/ml for ABTS) than those with methanol or water. In case of gooseberry by the DPPH test the water extract proved to be the most active (IC50 = 5.9 mg/ml). In the PCL test black currants methanol 50% extract was over 6 times more powerful as the ones from red currants. In case of gooseberries, water extract presented the highest antioxidant activity (41.84 μmol AAE/g). In black currant cyanidin-3-glucoside was the major compound. Quercetin 3-O-glucoside was identified in each sample. From cinnamic acid derivatives neochlorogenic acid was present in black currants in the highest amount (356.33 μg/g)

SHMT1 1420 and MTHFR 677 variants are associated with rectal but not colon cancer

<p>Abstract</p> <p>Background</p> <p>Association between rectal or colon cancer risk and serine hydroxymethyltransferase 1 (<it>SHMT1</it>) C1420T or methylenetetrahydrofolate reductase (<it>MTHFR</it>) C677T polymorphisms was assessed. The serum total homocysteine (HCY), marker of folate metabolism was also investigated.</p> <p>Methods</p> <p>The <it>SHMT1 </it>and <it>MTHFR </it>genotypes were determined by real-time PCR and PCR-RFLP, respectively in 476 patients with rectal, 479 patients with colon cancer and in 461 and 478, respective controls matched for age and sex. Homocysteine levels were determined by HPLC kit. The association between polymorphisms and cancer risk was evaluated by logistic regression analysis adjusted for age, sex and body mass index. The population stratification bias was also estimated.</p> <p>Results</p> <p>There was no association of genotypes or diplotypes with colon cancer. The rectal cancer risk was significantly lower for <it>SHMT1 </it>TT (OR = 0.57, 95% confidence interval (CI) 0.36-0.89) and higher for <it>MTHFR </it>CT genotypes (OR = 1.4, 95%CI 1.06-1.84). A gene-dosage effect was observed for <it>SHMT1 </it>with progressively decreasing risk with increasing number of T allele (p = 0.014). The stratified analysis according to age and sex revealed that the association is mainly present in the younger (< 60 years) or male subgroup. As expected from genotype analysis, the <it>SHMT1 </it>T allele/<it>MTHFR </it>CC diplotype was associated with reduced rectal cancer risk (OR 0.56, 95%CI 0.42-0.77 vs all other diplotypes together). The above results are unlikely to suffer from population stratification bias. In controls HCY was influenced by <it>SHMT1 </it>polymorphism, while in patients it was affected only by Dukes' stage. In patients with Dukes' stage C or D HCY can be considered as a tumor marker only in case of <it>SHMT1 </it>1420CC genotypes.</p> <p>Conclusions</p> <p>A protective effect of <it>SHMT1 </it>1420T allele or <it>SHMT1 </it>1420 T allele/<it>MTHFR </it>677 CC diplotype against rectal but not colon cancer risk was demonstrated. The presence of <it>SHMT1 </it>1420 T allele significantly increases the HCY levels in controls but not in patients. Homocysteine could be considered as a tumor marker in <it>SHMT1 </it>1420 wild-type (CC) CRC patients in Dukes' stage C and D. Further studies need to clarify why <it>SHMT1 </it>and <it>MTHFR </it>polymorphisms are associated only with rectal and not colon cancer risk.</p

Double-Diffusive Convection in Traveling Waves in the Iodate-Sulfite System Explained

Keresztessy et al. investigated traveling fronts of the oxidation of sulfite by iodate and determined that the isothermal density changes (Δρc) and enthalpy were both negative. According to the Pojman−Epstein model, only simple convection should occur in this case unless two species have significantly different diffusion coefficients. In fact, curved descending fronts with velocities greater than the ascending ones and “fingering” were observed. We have found that the diffusion coefficient of sulfuric acid is sufficiently larger than those of the other species to cause double-diffusive convection. We confirmed this by performing experiments with layers of solutions composed of components of the reactive system. Thus, the Pojman−Epstein model is upheld

Convective Chemical Fronts in the 1,4-Cyclohexanedione-Bromate-Sulfuric Acid-Ferroin System

Traveling waves were investigated in the Belousov−Zhabotinsky reaction in which 1,4-cyclohexanedione was the substrate. Isothermal density change (Δρc) and reaction enthalpy were determined. Δρc is positive, while the reaction enthalpy is negative; therefore, double-diffusive convection was expected according to the Pojman−Epstein model. Experiments were carried out in tubes and in spectrophotometric cells. In tubes the effect of the diameter and the orientation of the tube on the wave velocity and on the wave shape was studied; gravitational anisotropy and the expected double-diffusive convection were found. Experiments in cells were compared to the calculations of Wu et al. (Wu, Y.; Vasquez, D. A.; Edwards, B. F.; Wilder, J. W. Phys. Rev. E 1995, 51, 1119−1127). They predicted a critical cell width under which no simple convection should occur. However, because double-diffusive convection was observed, their calculations are not directly applicable