Environmental and spatial processes influencing phytoplankton biomass along a reservoirs‐river‐floodplain lakes gradient: A metacommunity approach

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Genetic analysis of rabies virus isolates in the Philippines

To determine the genetic characteristics of the rabies virus in the Philippines, 59 rabies virus isolates were obtained from domestic rabid dogs and their partial nucleotide sequences of nucleoprotein (N) gene were compared. Based on comparison with reported sequences, phylogenetic analysis revealed that all isolates from the Philippines had close genetic relations and formed two subgroups. The Philippines isolates belonged to a different lineage from other Asian isolates but were closer to them than to terrestrial isolates and laboratory strains. Several specific nucleotide and amino acid substitutions were observed among the Philippines isolates. Our results suggest that rabies viruses in the Philippines might have a characteristic evolution.     

IFNL4 ss469415590 Variant Shows Similar Performance to rs12979860 as Predictor of Response to Treatment against Hepatitis C Virus Genotype 1 or 4 in Caucasians

Objectives

The rs12979860 variant, linked to IL28B gene, predicts sustained viral response (SVR) to pegylated-interferon/ribavirin (pegIFN/RBV) therapy in Hepatitis C Virus genotype 1 or 4 (HCV-1/4)-infected patients. Recently, a functional variant, ss469415590, in linkage disequilibrium (LD) with rs12979860, has been discovered. Our objective was to assess the value of ss469415590 to predict SVR to pegIFN/RBV in Caucasian HCV-1/4-infected individuals and to compare its performance with that of rs12979860.

Methods

272 Caucasian HCV-1/4-infected patients who completed a course of pegIFN/RBV were genotyped for both rs12979860 and ss469415590 markers. Logistic regression models including factors with univariate association with SVR and each genetic marker were elaborated. The area under the receiver operating-characteristic curve (AUROC) was calculated for each model and both were compared.

Results

Both markers were in LD (r² = 0.82). For rs12979860, 66 (64.0%) CC versus 56 (33.1%) T allele carriers achieved SVR (Adjusted OR = 4.156, 95%CI = 2.388–7.232, p = 4.647×10⁻⁷). For ss469415590, 66 (66.0%) TT/TT versus 56 (32.5%) –G allele carriers (Adjusted OR = 4.783, 95%CI = 2.714–8.428, p = 6.153×10⁻⁸) achieved SVR. The AUROC of the model including rs12979860 was 0.742 (95%CI = 0.672–0.813) and of that based on ss469415590 was 0.756 (95%CI = 0.687–0.826) (p = 0.780).

Conclusions

The ss469415590 variant shows an equivalent performance to predict SVR to pegIFN/RBV than the rs2979860 in Caucasian HCV-1/4-infected patients.     

Complexes of heparin with poly(alkylenimines): Competitive binding with methylene blue

The binding of heparin (Hep) and Hep fractions with oligo- and poly-(alkylenimines) having the general formula H₂N(CH₂-CHR-NH)_nH, where R = H or Me, has been investigated by spectroscopy, by evaluating the competition of the amines and Methylene Blue for the anionic sites of Hep. The strongest-binding was observed at pH 3.5, with the essentially linear triethylenetetramine and the slightly branched tetraethylenepentamine giving the most stable complexes. For N (number of nitrogen atoms per molecule) >5, a decrease of the binding ability of the amines was observed. The apparent stoichiometry of the complexes was a function of the relative concentration of Hep and the amine, indicating an equilibrium between different types of complexes. Beef-lung Hep and a Hep fraction consisting mainly of trisulphated disaccharide blocks gave stronger complexes than the more heterogeneous, pigmucosal Hep and a Hep fraction of lower sulphate content. The results are interpreted in terms of polyelectrolyte-type associations involving sulphate groups on adjacent residues of the Hep chain and sequences of charged nitrogen atoms on the polyamine.     

Long-term effect of glucagon administration on rat liver L-type pyruvate kinase.

After 5 h of treatment with glucagon, liver L-type pyruvate kinase (ATP: pyruvate 2-0-phosphotransferase; EC 2.7.1.40) showed a significant decrease of K0.5 and the Hill coefficient (nH) in the absence of fructose 1,6-diphosphate. However, in the presence of fructose 1,6-diphosphate, liver enzymes from treated rats showed a slight decrease of K0.5 but nH remained unchanged. In both circumstances, no changes of Vmax were observed after treatment. These changes in the kinetic properties of liver L-type pyruvate kinase are consistent with the dephosphorylation of the enzyme caused by insulin release in response to treatment with glucagon.     

Changes in the liver lactate dehydrogenase isozyme profile after induced glycogenolysis

Summary Treatment with cystamine, phlorrhizin or nicotinic acid, which induced liver glycogenolysis, resulted in the increase of liver lactate dehydrogenase activity. This increase was counteracted by the administration of cycloheximide or actinomycin D and coincided with the increase of isozymes 4 and 3 and the decrease of isozyme 5. The enhancement of liver lactate dehydrogenase activity and the changes observed in the isozyme profile were similar to those observed after starvation. These results suggest that the changes in the lactate dehydrogenase isozyme profile found after cystamine, phlorrhizin or nicotinic acid administration may be related to the glycogenolysic effect of these compounds. These result in an adaptation of the liver lactate dehydrogenase to gluconeogenesis.     

A map of rye chromosome 2R using isozyme and morphological markers

Summary The segregation of isozymic loci for leaf peroxidases (L2Per) has been investigated in backcrosses and F₂ offspring of rye lines having purple seeds (Ps) and monstrosum ears (mo). The Ps, L2Per-3b, mo, and L2Per-2 loci were linked. The Ps and mo loci have been previously located on the 2R chromosome, and the L2Per-3b and L2Per-2 loci have been located on the 2RS chromosome arm. The results favor the gene order Ps ... L2Per-3b ... mo ... L2Per-2 or Ps ... mo... L2Per-3b ... L2Per-2. The position of the loci relative to the centromere is still not known, but the obtained results suggest that the mo locus could be located on the 2RS chromosome arm. On the basis of previously reported linkage groups, the most probable arrangement of the loci located on chromosome 2R is: dw2 ... Ps ... (L2Per-3a ... L2Per-3b ... mo) ... L2Per-2. It has not been possible to know the position of L2Per-4 loci (also located on 2RS chromosome arm) relative to L2Per-3a and L2Per-3b loci.     

Lactic acid bacteria: hydrophobicity and strength of attachment to meat surfaces

The hydrophobicity and strength of a ttachment of several lactic acid bacteria with antimicrobial activity were studied. Hydrophobicity was determined by bacterial adherence to hydrocarbons (BATH; octane or xylene), adhesion to nitrocellulose filters (NCF), salt aggregation test (SAT) and adherence to phenyl–Sepharose beads (PSB). The relative hydrophobicity of lactic acid bacteria depended markedly on the method used. No correlation between either SAT or BATH (octane) and strength of attachment (Sr value) existed. However, a significant relationship between strength of attachment and BATH (xylene), NCF and PSB, respectively, was observed, showing the highest correlation coefficient ( r = 0·778) for BATH (xylene).     

Glycosaminoglycans of the plasma membranes of renal tubule and liver cells

Glycosaminoglycans were isolated from plasma membranes of hepatic and renal tubule cells of guinea pig. Plasmalemma of renal tubule cells contained more total glycosaminoglycans, hyaluronic acid, chondroitin-4 sulfates and chondroitin-6 sulfates, and less dermatan sulfates and heparin sulfates than liver plasma membranes. These glycocalyx components, owing to their polyanionic properties, may have a role in the transport of water, ions, and macromolecules across the cell membrane.