Species traits and catchment‐scale habitat factors influence the occurrence of freshwater mussel populations and assemblages

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The first report on the characterization of a virus isolated from Allomyrina dichotoma in the Republic of Korea

This report reveals the structure of a virus extracted from the Korean horn beetle Allomyrina dichotoma. The purified virus particle was 100% identical to Allomyrina virus lef‐8 sequence registered as KM_233709.1. The structure of this virus was confirmed to be closely related to that of the Nudiviridae family, and it was rod shaped and enveloped, and observed to be of approximately the mean length of a single viral nucleocapsid of 200–210 nm and mean diameter of 100–110 nm. These results provide an insight into the structural characteristics of the Nudiviridae family that can be used for nudiviral identification.     

The inhibition of T-cells proliferation by mouse mesenchymal stem cells through the induction of p16INK4A-cyclin D1/cdk4 and p21waf1, p27kip1-cyclin E/cdk2 pathways

Mesenchymal stem cells (MSCs) have been shown to down-regulate T-cell responses. However, the mechanisms underlying remain unknown. In this study, we report that BALB/c bone marrow-derived MSCs inhibit the proliferation of allogeneic T-cells in mixed lymphocyte reactions (MLR), This inhibition is dependent on cell-cell contact, and do not induce apoptosis. Furthermore, cell-cycle analyses reveal that T-cells, in the presence of MSCs, are arrested in the G0/G1 phase through. The blockage of phosphorylation of retinoblastoma protein (Rb), mediated by the p16(INK4A)-cyclin D1/cdk4 complex and p21(waf1), p27(kip1)-cyclin E/cdk2 complex pathway. Our results suggest that MSCs may perform a crucial function in the maintenance of immune homeostasis, via direct regulation of the clonal expansion of activated T-cells. The novel T-cell regulatory mechanism exhibited by MSCs may prove useful in a variety of therapeutic applications.     

Parasites in peril: abundance of batflies (Diptera: Nycteribiidae) declines along an urbanisation gradient

Journal of Insect Conservation - Urbanisation has a wide range of impacts on biodiversity, but its effects on parasitic arthropods, particularly those of bats, remain poorly studied. Ectoparasites...     

Novel secondary Ig VH gene rearrangement and in-frame Ig heavy chain complementarity-determining region III insertion/deletion variants in de novo follicular lymphoma

Human germinal center B cell tumors retain the ability of their nontransformed counterparts to somatically hypermutate Ig V genes by nucleotide substitution. Among a survey of 60 primary previously untreated, clonal, follicular lymphomas we have identified a rare V(H) rearrangement variant and two other in-frame nucleotide insertion/deletion variants within complementarity-determining region III of the Ig heavy chain. The neoplastic origin of the V(H) rearrangement variant was directly demonstrated in cells isolated by microdissection from malignant follicles. In all three cases a common clonal origin for the variants was demonstrated by complementarity-determining region III nucleotide sequence homology and shared somatic mutations in germline encoded positions in framework region IV. The monoclonal nature of the tumors was independently confirmed by demonstrating a single t(14;18) translocation breakpoint in the two cases with a detectable translocation. All the variants occurred in functional V(H) rearrangements, which in two cases were directly shown to encode functional Ab molecules. Both recombination-activating genes 1 and 2 were expressed in lymph node tumor cells containing the V(H) rearrangement variant, although recombination-activating gene expression among a panel of lymphomas was not limited to this variant.     

LvsA, a protein related to the mouse beige protein, is required for cytokinesis in Dictyostelium

We isolated a Dictyostelium cytokinesis mutant with a defect in a novel locus called large volume sphere A (lvsA). lvsA mutants exhibit an unusual phenotype when attempting to undergo cytokinesis in suspension culture. Early in cytokinesis, they initiate furrow formation with concomitant myosin II localization at the cleavage furrow. However, the furrow is later disrupted by a bulge that forms in the middle of the cell. This bulge is bounded by furrows on both sides, which are often enriched in myosin II. The bulge can increase and decrease in size multiple times as the cell attempts to divide. Interestingly, this phenotype is similar to the cytokinesis failure of Dictyostelium clathrin heavy-chain mutants. Furthermore, both cell lines cap ConA receptors but form only a C-shaped loose cap. Unlike clathrin mutants, lvsA mutants are not defective in endocytosis or development. The LvsA protein shares several domains in common with the molecules beige and Chediak-Higashi syndrome proteins that are important for lysosomal membrane traffic. Thus, on the basis of the sequence analysis of the LvsA protein and the phenotype of the lvsA mutants, we postulate that LvsA plays an important role in a membrane-processing pathway that is essential for cytokinesis.     

The effect of sugar,amino acid,metal ion,and NaCl on model Maillard reaction under pH control

Summary. The color intensities was determined of Maillard reaction products (MRPs) prepared by heating each of five sugars (maltose, fructose, glucose, arabinose, and xylose) with each of 12 amino acids (aspartic acid, glutamic acid, alanine, leucine, isoleucine, valine, proline, serine, cysteine, phenylalanine, arginine, and lysine). The remaining percentages of glucose and rate of change of color intensity due to the addition of a metal ion and NaCl were monitored for nine MRPs that had been formed between glucose and each of nine amino acids (aspartic acid, glutamic acid, alanine, valine, serine, cysteine, phenylalanine, arginine, and lysine). Model MRPs were prepared in a block heater at 100°C for 1–12h with the pH value controlled at 6.5. The resulting color intensity of each MRPs formed from the basic amino acids was greater due to the higher reactivity than those from the acidic amino acids. The remaining percentage of glucose in each MRPs from the basic amino acids was lower than those from the acidic amino acids. The MRPs from the nonpolar amino acids showed an intermediate color intensity and remaining percentages of glucose between those formed from the basic and acidic amino acids. Browning tended to be accelerated in the presence of metal ions, especially Fe²⁺ and Cu²⁺, although it was affected by the property of the amino acid and heating time as well as by the type of metal ion. On the other hand, browning was greatly inhibited by a high concentration of NaCl.     

Synthesis and evaluation of lasonolide A analogues

Homolasonolide A and 10-desmethyllasonolide A are biologically less active than lasonolide A. The ethyl ester analogue of lasonolide A exhibited higher activity than the parent compound in some biological test.