Removal of chromate anions from aqueous stream by a cationic surfactant-modified yeast

The removal of chromate anions (CrO(4)(2-)) from aqueous solution by a cationic surfactant-modified yeast was studied in a batch system. Cetyl trimethyl ammonium bromide (CTAB) was used for biomass modification; it substantially improved the biosorption efficiency. The influences of solution pH, CrO(4)(2-) anion concentrations and biomass concentration on the biosorption efficiency were investigated. The biosorption of chromate anions by modified yeast was strongly affected by pH. The optimum pH for biosorption of CrO(4)(2-) by modified yeast was 4.5-5.5. Zeta potential values of modified and unmodified yeast were determined at various pH values. Concentrations ranging from 5.2 to 208 mg/l Cr(VI) were tested and the biosorptive removal efficiency of the metal ions from aqueous solution was more than 99.5%. Freundlich and Langmuir isotherms were used to evaluate the data and the regression constants were determined.     

Agonist internalization by cloned Y1 neuropeptide Y (NPY) receptor in Chinese hamster ovary cells shows strong preference for NPY,endosome-linked entry and fast receptor recycling

In Chinese hamster ovary (CHO) cells expressing the cloned guinea-pig Y1 receptor, the saturable, receptor-linked internalization of NPY (NPY)-related peptides showed the rank order of human/rat neuropeptide Y (hNPY)>pig/rat peptide YY (pPYY)>=(Pro(34))human PYY>(Leu(31),Pro(34))hNPY>(Leu(31),Pro(34))hPYY>BVD-11 (a selective Y1 antagonist). All agonists accessed similar numbers of Y1 sites in particulates from disrupted cells, with relatively small affinity variation. The rate of internalization could significantly depend on the overall interactivity of the agonist peptide (reflected in sensitivity to chaotropic agents, as well as in the level of non-saturable binding and internalization). Concentration-dependent inhibition of the agonist-driven CHO-Y1 internalization was found with filipin III (a cholesterol-complexing macrolide), and confirmed with inhibitors of clathrin lattice formation, phenylarsine oxide (PAO) and sucrose. In the concentration range affecting Y1 internalization, none of the above treatments or agents significantly alter agonist affinity for Y1 cell surface or particulate receptors. Largely similar responses to the above inhibitors were observed in CHO-Y1 cells for internalization of human transferrin. Internalization of CHO-Y1 receptor apparently is driven by NPY in strong preference to other naturally encountered agonists. At 37 degrees C, most of the internalized receptor is rapidly recycled through endosome-like membrane elements, detectable in Percoll gradients.     

The effect of clopidogrel on apoptosis--an in vivo study

Clopidogrel is widely used in cardiovascular medicine, and is believed to play an important role in the pathogenesis of many cardiovascular disease processes. In particular, patients undergoing coronary stenting, who are commonly treated with clopidogrel, are candidates for in-stent restenosis. This is mainly caused by neointimal hyperplasia, so it is important to consider whether clopidogrel affects neointimal hyperplasia via apoptosis. Lymphocytes, especially T-cells, are known to play a key role in the initiation and formation of atherosclerotic plaques. The aim of this study was to investigate the effect of clopidogrel on human lymphocyte apoptosis, using a DNA fragmentation assay.     

Leptin levels increase during flutamide therapy in women with polycystic ovary syndrome

AIM: To evaluate the serum leptin levels and the effects of flutamide treatment on the leptin levels in women with polycystic ovary syndrome (PCOS). METHODS: 20 women with PCOS and 20 controls were enrolled in the study. Leptin levels and leptin response to an oral glucose tolerance test were assessed in both groups before and after a 4-week flutamide therapy period. RESULTS: The leptin levels were similar in both groups at baseline. In the PCOS group, leptin levels and area under curve for leptin levels increased significantly after flutamide treatment. CONCLUSIONS: Women with PCOS had similar leptin levels to those of controls with similar age and body mass index. Flutamide treatment led to increased leptin levels and leptin responses to oral glucose tolerance tests in PCOS patients. Further studies are needed to gain insights into the clinical consequences of these effects of flutamide.     

The small RNA profile during Drosophila melanogaster development

Small RNAs ranging in size between 20 and 30 nucleotides are involved in different types of regulation of gene expression including mRNA degradation, translational repression, and chromatin modification. Here we describe the small RNA profile of Drosophila melanogaster as a function of development. We have cloned and sequenced over 4000 small RNAs, 560 of which have the characteristics of RNase III cleavage products. A nonredundant set of 62 miRNAs was identified. We also isolated 178 repeat-associated small interfering RNAs (rasiRNAs), which are cognate to transposable elements, satellite and microsatellite DNA, and Suppressor of Stellate repeats, suggesting that small RNAs participate in defining chromatin structure. rasiRNAs are most abundant in testes and early embryos, where regulation of transposon activity is critical and dramatic changes in heterochromatin structure occur.     

A Positively Selected MAGEE2 LoF Allele Is Associated with Sexual Dimorphism in Human Brain Size and Shows Similar Phenotypes in Magee2 Null Mice

A nonsense allele at rs1343879 in human MAGEE2 on chromosome X has previously been reported as a strong candidate for positive selection in East Asia. This premature stop codon causing ∼80% protein truncation is characterized by a striking geographical pattern of high population differentiation: common in Asia and the Americas (up to 84% in the 1000 Genomes Project East Asians) but rare elsewhere. Here, we generated a Magee2 mouse knockout mimicking the human loss-of-function mutation to study its functional consequences. The Magee2 null mice did not exhibit gross abnormalities apart from enlarged brain structures (13% increased total brain area, P = 0.0022) in hemizygous males. The area of the granular retrosplenial cortex responsible for memory, navigation, and spatial information processing was the most severely affected, exhibiting an enlargement of 34% (P = 3.4×10⁻⁶). The brain size in homozygous females showed the opposite trend of reduced brain size, although this did not reach statistical significance. With these insights, we performed human association analyses between brain size measurements and rs1343879 genotypes in 141 Chinese volunteers with brain MRI scans, replicating the sexual dimorphism seen in the knockout mouse model. The derived stop gain allele was significantly associated with a larger volume of gray matter in males (P = 0.00094), and smaller volumes of gray (P = 0.00021) and white (P = 0.0015) matter in females. It is unclear whether or not the observed neuroanatomical phenotypes affect behavior or cognition, but it might have been the driving force underlying the positive selection in humans.     

Effects of red wine consumption on serum paraoxonase/arylesterase activities and on lipoprotein oxidizability in healthy-men

Although there is a general consensus concerning the lower risk for cardiovascular disease in moderate drinkers, the mechanisms responsible for the cardioprotective effect of red wine remain unknown. It has been proposed that increased serum paraoxonase activity may be a mechanism of action underlying reduced cardiovascular disease risk in moderate drinkers, since paraoxonase inhibits lipoprotein oxidation. The aim of this study was to investigate the effects of red wine consumption on serum paraoxonase/arylesterase activities and on lipoprotein oxidizability in healthy-men. Fourteen healthy-men were included in the study. The subjects consumed 0.375 g alcohol / kg body weight for 3 weeks. Paraoxonase and arylesterase activities were studied spectrophotometrically. Oxidizability of apolipoprotein B-containing lipoproteins were determined, after separating them with precipitation method, by incubating with copper-sulfate. Paraoxonase activity did not change, however arylesterase activity significantly decreased after red wine consumption (P < 0.01). There was a reduced susceptibility of apolipoprotein B-containing lipoproteins to copper-sulfate induced oxidation after red wine consumption (P < 0.01). Our results support that red wine protects lipoproteins against oxidation, however there was not any significant change in serum paraoxonase activity after red wine consumption.KEY WORDS: Red wine; Paraoxonase; Arylesterase; Lipoprotein oxidation