Paraoxonase Arg 192 allele is an independent risk factor for three-vessel stenosis of coronary artery disease

The role of the paraoxonase (PON1) codon 192 polymorphism [glutamine (Q)/arginine (R)] in coronary artery disease (CAD) is controversial. The aim of the present study was to evaluate whether the PON1 gene polymorphism is an independent risk factor for severity of coronary artery disease in patients from west of Iran. The PON1-Arg-192 genotypes were detected by PCR-RFLP in 414 individuals undergoing their first coronary angiography. Patients were placed into one of two groups: CAD and control without CAD or diabetes. The frequency of PON1-Arg-192 allele was significantly higher in the CAD (23.4 vs. 16%, P = 0.032) than in the control group and there was a higher risk of developing CAD (OR = 1.6, P = 0.02). In addition, this difference remained significant after adjustment for without history of diabetes (OR = 1.47, P = 0.048), presence of normolipidemia and absence of history of blood pressure (OR = 1.4, P = 0.05). This result indicated PON1-Arg-192 allele is a risk factor of CAD also when correcting for conventional risk factors. We found a significant association between the PON1-Arg-192 genotype (QR + RR) and the extent of CAD in CAD patients and CAD subjects without diabetes, represented by the increased frequency of three-vessel disease with OR = 1.49, P = 0.046; χ2 = 3.82, P = 0.048 and OR = 1.46, P = 0.05; χ2 = 3.48, P = 0.051, respectively. The CAD patients carrying PON1-Arg-192 genotype (QR + RR) had lower plasma HDL-C level (P = 0.019) and higher plasma LDL-C(P = 0.01) and TG(P = 0.05). Our results indicated that PON1-Arg-192 allele can be important independent risk factor of CAD in a west population of Iran, with carriers of PON1-Arg-192 having an increased frequency of three-vessel disease and also having a distinct plasma lipids profile. Larger collaborative studies are needed to confirm these results.     

Cloning and expression of human IFN-γ in <Emphasis Type="Italic">Leishmania tarentolae</Emphasis>

Increasing therapeutic applications for recombinant human interferon-gamma (rhIFN-γ), an antiviral pro-inflammatory cytokine, has broadened interest in optimizing methods for its production. We herein describe a unicellular eukaryotic system, Leishmania tarentolae, a Trypanosomatidae protozoan parasite of gecko Tarentola annularis, which has recently been introduced as a candidate for heterologous gene expression. In this study, the hIFN-γ cDNA was amplified from phyto-hemagglutinin-stimulated peripheral blood mononuclear cells of a healthy blood donor using RT–PCR. In order to express, the rhIFN-γ protein, the resulting cDNA was cloned in two expression cassettes (each containing one copy of hIFN-γ cDNA) and integrated into the small subunit of ribosomal RNA gene of L. tarentolae genome by electroporation. Transformed clones were selected in the presence of appropriate antibiotics. Western blotting of rhIFN-γ and ELISA confirmed the expression and production of 9.5 mg of rhIFN-γ protein/l respectively.     

Accuracies of genomic breeding values in American Angus beef cattle using K-means clustering for cross-validation

Background

Genomic selection is a recently developed technology that is beginning to revolutionize animal breeding. The objective of this study was to estimate marker effects to derive prediction equations for direct genomic values for 16 routinely recorded traits of American Angus beef cattle and quantify corresponding accuracies of prediction.

Methods

Deregressed estimated breeding values were used as observations in a weighted analysis to derive direct genomic values for 3570 sires genotyped using the Illumina BovineSNP50 BeadChip. These bulls were clustered into five groups using K-means clustering on pedigree estimates of additive genetic relationships between animals, with the aim of increasing within-group and decreasing between-group relationships. All five combinations of four groups were used for model training, with cross-validation performed in the group not used in training. Bivariate animal models were used for each trait to estimate the genetic correlation between deregressed estimated breeding values and direct genomic values.

Results

Accuracies of direct genomic values ranged from 0.22 to 0.69 for the studied traits, with an average of 0.44. Predictions were more accurate when animals within the validation group were more closely related to animals in the training set. When training and validation sets were formed by random allocation, the accuracies of direct genomic values ranged from 0.38 to 0.85, with an average of 0.65, reflecting the greater relationship between animals in training and validation. The accuracies of direct genomic values obtained from training on older animals and validating in younger animals were intermediate to the accuracies obtained from K-means clustering and random clustering for most traits. The genetic correlation between deregressed estimated breeding values and direct genomic values ranged from 0.15 to 0.80 for the traits studied.

Conclusions

These results suggest that genomic estimates of genetic merit can be produced in beef cattle at a young age but the recurrent inclusion of genotyped sires in retraining analyses will be necessary to routinely produce for the industry the direct genomic values with the highest accuracy.     

Hydrodynamic vaccination with DNA encoding an immunologically privileged retinal antigen protects from autoimmunity through induction of regulatory T cells

The eye is an immunologically privileged organ whose Ags serve as targets for experimental autoimmune uveitis (EAU), a model for human uveitis. We used a hydrodynamic i.v. injection of naked DNA to express the uveitogenic retinal Ag interphotoreceptor retinoid-binding protein (IRBP) in the periphery, thus revoking its immune-privileged status. IRBP was expressed in the liver within hours of administration of as little as 10 microg of IRBP-DNA. Vaccinated mice were highly protected from EAU induced by immunization with IRBP for at least 10 wk after vaccination. Protection was partial in a reversal protocol. Mechanistic studies revealed specific hyporesponsiveness to IRBP without immune deviation, no evidence for apoptosis either by the Fas- or Bcl-2-regulated (mitochondrial) pathway and apparent lack of dependence on CD8(+) cells, IL-10, or TGF-beta. In contrast, depletion of CD25(+) cells after vaccination and before challenge markedly abrogated protection. IRBP-specific CD4(+)CD25(high) T cells could be cultured from vaccinated mice and transferred protection to unvaccinated, EAU-challenged recipients. In vitro characterization of these cells revealed that they are Ag specific, anergic, express FoxP3, CTLA-4, and glucocorticoid-induced TNFR, and suppress by contact. Thus, expression of IRBP in the periphery by DNA vaccination results in tolerance that acts at least in part through induction of IRBP-specific, FoxP3(+)CD4(+)CD25(+) regulatory T cells. DNA vaccination may offer a new approach to Ag-specific therapy of uveitis.     

The role of alkyl chain length in the inhibitory effect n-alkyl xanthates on mushroom tyrosinase activities

Sodium salts of four n-alkyl xanthate compounds, C2H5OCS2Na (I), C3H7OCS2Na (II), C4H9OCS2Na (III), and C6H13OCS2Na (IV) were synthesized and examined for inhibition of both cresolase and catecholase activities of mushroom tyrosinase (MT) in 10 mM sodium phosphate buffer, pH 6.8, at 293 K using UV spectrophotometry. 4-[(4-Methylbenzo)azo]-1,2-benzendiol (MeBACat) and 4-[(4-methylphenyl)azo]-phenol (MePAPh) were used as synthetic substrates for the enzyme for catecholase and cresolase reactions, respectively. Lineweaver-Burk plots showed different patterns of mixed, competitive or uncompetitive inhibition for the four xanthates. For the cresolase activity, I and II showed uncompetitive inhibition but III and IV showed competitive inhibition pattern. For the catecholase activity, I and II showed mixed inhibition but III and IV showed competitive inhibition. The synthesized compounds can be classified as potent inhibitors of MT due to their Ki values of 13.8, 11, 8 and 5 microM for the cresolase activity, and 1.4, 5, 13 and 25 microM for the catecholase activity for I, II, III and IV, respectively. For the catecholase activity both substrate and inhibitor can be bound to the enzyme with negative cooperativity between the binding sites (alpha > 1) and this negative cooperativity increases with increasing length of the aliphatic tail of these compounds. The length of the hydrophobic tail of the xanthates has a stronger effect on the Ki values for catecholase inhibition than for cresolase inhibition. Increasing the length of the hydrophobic tail leads to a decrease of the Ki values for cresolase inhibition and an increase of the Ki values for catecholase inhibition.     

A defect in the ionotropic glutamate receptor 6 gene (GRIK2) is associated with autosomal recessive mental retardation

Nonsyndromic mental retardation is one of the most important unresolved problems in genetic health care. Autosomal forms are far more common than X-linked forms, but, in contrast to the latter, they are still largely unexplored. Here, we report a complex mutation in the ionotropic glutamate receptor 6 gene (GRIK2, also called “GLUR6”) that cosegregates with moderate-to-severe nonsyndromic autosomal recessive mental retardation in a large, consanguineous Iranian family. The predicted gene product lacks the first ligand-binding domain, the adjacent transmembrane domain, and the putative pore loop, suggesting a complete loss of function of the GLU_K6 protein, which is supported by electrophysiological data. This finding provides the first proof that GLU_K6 is indispensable for higher brain functions in humans, and future studies of this and other ionotropic kainate receptors will shed more light on the pathophysiology of mental retardation.     

TH17 cells contribute to uveitis and scleritis and are expanded by IL-2 and inhibited by IL-27/STAT1

T-helper type 17 cells (T(H)17) are implicated in rodent models of immune-mediated diseases. Here we report their involvement in human uveitis and scleritis, and validate our findings in experimental autoimmune uveoretinitis (EAU), a model of uveitis. T(H)17 cells were present in human peripheral blood mononuclear cells (PBMC), and were expanded by interleukin (IL)-2 and inhibited by interferon (IFN)-gamma. Their numbers increased during active uveitis and scleritis and decreased following treatment. IL-17 was elevated in EAU and upregulated tumor necrosis factor (TNF)-alpha in retinal cells, suggesting a mechanism by which T(H)17 may contribute to ocular pathology. Furthermore, IL-27 was constitutively expressed in retinal ganglion and photoreceptor cells, was upregulated by IFN-gamma and inhibited proliferation of T(H)17. These findings suggest that T(H)1 cells may mitigate uveitis by antagonizing the T(H)17 phenotype through the IFN-gamma-mediated induction of IL-27 in target tissue. The finding that IL-2 promotes T(H)17 expansion provides explanations for the efficacy of IL-2R antibody therapy in uveitis, and suggests that antagonism of T(H)17 by IFN-gamma and/or IL-27 could be used for the treatment of chronic inflammation.     

Serum level and tumor tissue expression of Ribonucleotide-diphosphate Reductase subunit M2 B: a potential biomarker for colorectal cancer

Molecular Biology Reports - This study explored the applicability of serum level and tissue expression of Ribonucleotide-diphosphate Reductase subunit M2 B (RRM2B) as reliable biomarkers for...     

Salicylic Acid,as a Positive Regulator of Isochorismate Synthase,Reduces the Negative Effect of Salt Stress on Pistacia vera L. by Increasing Photosynthetic Pigments and Inducing Antioxidant Activity

Salinity, as a serious and prevalent abiotic stress, causes widespread crop losses by restricting plant growth and production throughout the world. In this study, the biochemical and molecular responses of the pistachio (Pistacia vera L.) plant were studied under NaCl and salicylic acid (SA) treatments using hydroponically grown salt tolerant (Ghazvini) and salt sensitive (Sarakhs) pistachio cultivars. NaCl treatment (250 mM) increased the production of hydrogen peroxide (H₂O₂) and malondialdehyde (MDA) and the activity of antioxidant enzymes in both cultivars. In the sensitive cultivar, the H₂O₂ content was higher than the tolerant cultivar, especially in the roots. SA application to both salt-stress-treated cultivars resulted in an increase in photosynthetic pigment contents and antioxidant enzyme activity and a decrease in the H₂O₂ and MDA contents. After NaCl treatment, the isochorismate synthase (ICS) gene was upregulated in Ghazvini which leads to an increase in the SA content of the salt tolerant pistachio cultivar. In contrast, the salt treatment downregulated the expression of the ICS gene in Sarakhs. The ICS gene expression was positively regulated by SA treatment under the salt stress condition. Our results suggest that Ghazvini has higher salinity tolerance than Sarakhs due to its higher antioxidant capacity, photosynthetic pigment content, and the cultivar-specific expression pattern of the ICS gene. In this study, the potential alleviative effects of SA on the adverse effect of salt stress in P. vera (Pistacia vera) were also identified and highlighted.