Quantitative assessment of the influence of PPARG P12A polymorphism on gestational diabetes mellitus risk

The peroxisome proliferator-activated receptor-γ (PPARG) is a member of the nuclear hormone receptor superfamily that has attracted considerable attention as a candidate gene for gestational diabetes mellitus (GDM) based on its function as a key factor involved in the regulation of adipocyte differentiation as well as lipid and glucose metabolism and insulin sensitivity. Many studies have examined the association between P12A polymorphism (rs1801282) in the PPARG gene and risk of GDM, but the results have been inconsistent. To derive a more precise estimation of the relationship, a meta-analysis of 2,858 GDM patients and 6,890 controls from nine published case–control studies was performed. An overall random effects odds ratio of 0.89 (95 % confidence interval [CI]: 0.77–1.04, P = 0.15) was found for 12A allele. In the subgroup analysis by ethnicity, significantly decreased risks were found in East Asians, while no significant associations were detected among Caucasian and Middle Eastern populations. Similar results were also observed using dominant genetic model. This meta-analysis suggested an overall weak association between the P12A polymorphism and GDM risk among East Asians. However, additional very large-scale studies are warranted to provide conclusive evidence on the effects of the PPARG gene on risk of GDM.     

Generalized Subcutaneous Phaeohyphomycosis Caused by Phialophora verrucosa: Report of a Case and Review of Literature

We report a case of subcutaneous phaeohyphomycosis due to Phialophora verrucosa in a 64-year-old Chinese farmer suffering from CD4+ lymphopenia. He presented with diffuse and infiltrated plaques involving the entire face including the eyes, neck, occiput, and extending to the dorsal regions of his torso. The patient is notable for the discrete multifocal nature of the illness in the absence of disseminated infection and rarity of P. verrucosa as a cause of subcutaneous phaeohyphomycosis.     

Association between rs10118757(A/G) in methylthioadenosine phosphorylase gene and coronary artery disease in Chinese Hans

Studies focusing on the association of gene methylthioadenosine phosphorylase (MTAP) with the risk of coronary artery disease (CAD) and myocardial infarction (MI) are limited.     

Genotypic characteristics of a Mycobacterium sp. isolated from yellowtail Seriola quinqueradiata and striped jack Pseudocaranx dentex in Japan

In Japan, a Mycobacterium marinum‐like mycobacterium was isolated from the yellowtail, Seriola quinqueradiata. The species was identified as M. marinum by a commercial mycobacterial DNA‐DNA hybridization kit. Nevertheless, PCR restriction analysis of the DNA of its RNA polymerase β‐subunit gene definitively showed that this Mycobacterium sp. was M. ulcerans. PCR analysis revealed the genotypic characteristics of M. ulcerans in the Mycobacterium sp., only the mup053 gene sequence being absent, as has been found previously in other piscine mycobacteria such as M. marinum strains DL240490 and DL045 and M. pseudoshottsii. With one exception, this Mycobacterium sp. and M. pseudoshottsii had identical 16S rRNA gene sequences, which is also probably true of M. marinum strains DL240490 and DL045. Similarly, according to comparisons of the 16S rRNA gene, ITS region, and hsp65 gene sequences, this Mycobacterium sp. is more closely related to M. pseudoshottsii than to M. ulcerans or M. marinum. A PCR product of approximately 2000 bp was amplified from region of difference 9 in the Mycobacterium sp. The nucleotide sequence revealed insertion of IS2404, the sequence of which is 1366 bp long. The novel single nucleotide polymorphisms identified in this region distinguished this Mycobacterium sp. from M. marinum strain DL240490 and M. pseudoshottsii. The present findings raise the possibility that these species have a common ancestor. Further studies are required to improve our understanding of the relationship between their geographical origin and genetic diversity.     

Late Wenlock (Middle Silurian) global Bioevent: Possible chemical cause for mass graptolite mortalities

Graptolites nearly became extinct in the latest Wenlock in all preserved stratigraphic sequences of this age. Graptolite mortalities occurred along the western coast of Laurentia and at sites that surrounded the Proto‐Tethys. Graptolite mass mortalities took place among deep‐water, open ocean dwelling organisms. After the mass mortalities, only the Pristiograptus dubius group and retiolids surface or near‐surface dwellers, survived. For a period of time, little speciation or diversification occurred. The base of the Ludlow is marked by diversification, with appearances of S. colonus, M. nilssoni and other groups which occur in near surface waters. None of the extensive plate movements postulated for the Silurian readily explain the mass extinctions that occurred. During the Silurian, global temperatures were warmer than present and atmospheric oxygen concentrations were lower, creating extensive oceanic anoxia. Below the oxygenated surface layers of the ocean, was an anoxic, non‐sulfidic zone (i.e. nitrate‐reducing) above a sulfidic zone. Graptolites lived over a range of depth from the oxygenated zone to either near or in the nitrate‐reducing zones. As the oxygen concentration declined through the Silurian, the depth of the oxic zone would have become shoaler with expanding anoxia. Late Wenlock graptolites that were unable to migrate to shallower depths, living in borderline oxygen conditions, could have been killed, resulting in the mortalities of the late Wenlock. Only those graptolites that were surface dwellers survived, adapted and reradiated.     

Salvianolic acid B inhibits the amyloid formation of human islet amyloid polypeptideand protects pancreatic beta‐cells against cytotoxicity

The misfolding of human islet amyloid polypeptide (hIAPP) is regarded as one of the causative factors of type 2 diabetes mellitus (T2DM). Salvia miltiorrhiza (Danshen), one of the most commonly used of traditional Chinese medicines, is often used in Compound Recipes for treating diabetes, however with unclear mechanisms. Since salvianolic acid B (SalB) is the most abundant bioactive ingredient of salvia miltiorrhiza water‐extract. In this study, we tested whether SalB has any effect on the amyloidogenicity of hIAPP. Our results clearly suggest that SalB can significantly inhibit the formation of hIAPP amyloid and disaggregate hIAPP fibrils. Furthermore, photo‐crosslinking based oligomerization studies suggest SalB significantly suppresses the toxic oligomerization of hIAPP monomers. Cytotoxicity protection effects on pancreatic INS‐1 cells by SalB were also observed using MTT‐based assays, potentially due to the inhibition on the membrane disruption effects and attenuated mitochondria impairment induced by hIAPP. These results provide evidence that SalB may further be studied on the possible pharmacological treatment for T2DM. Proteins 2013. © 2012 Wiley Periodicals, Inc.     

ACA‐specific RNA sequence recognition is acquired via the loop 2 region of MazF mRNA interferase

MazF is an mRNA interferase that cleaves mRNAs at a specific RNA sequence. MazF from E. coli (MazF‐ec) cleaves RNA at A and CA. To date, a large number of MazF homologs that cleave RNA at specific three‐ to seven‐base sequences have been identified from bacteria to archaea. MazF‐ec forms a dimer, in which the interface between the two subunits is known to be the RNA substrate‐binding site. Here, we investigated the role of the two loops in MazF‐ec, which are closely associated with the interface of the MazF‐ec dimer. We examined whether exchanging the loop regions of MazF‐ec with those from other MazF homologs, such as MazF from Myxococcus xanthus (MazF‐mx) and MazF from Mycobacterium tuberculosis (MazF‐mt3), affects RNA cleavage specificity. We found that exchanging loop 2 of MazF‐ec with loop 2 regions from either MazF‐mx or MazF‐mt3 created a new cleavage sequence at (A/U)(A/U)AA and C in addition to the original cleavage site, A and CA, whereas exchanging loop 1 did not alter cleavage specificity. Intriguingly, exchange of loop 2 with 8 or 12 consecutive Gly residues also resulted in a new RNA cleavage site at (A/U)(A/U)AA and C. The present study suggests a method for expanding the RNA cleavage repertoire of mRNA interferases, which is crucial for potential use in the regulation of specific gene expression and for biotechnological applications. Proteins 2013. © 2012 Wiley Periodicals, Inc.