UGT1A6 Polymorphisms Modulated Lung Cancer Risk in a Chinese Population

Uridine diphosphoglucuronosyltransferases (UGTs) 1A6 is the only UGT1A isoform expressed in lung tissue. It is responsible for the detoxification of carcinogens such as benezo[a]pyrene from cigarette smoke. The purpose of this study was to evaluate the association of UGT1A6 polymorphisms and haplotypes with lung cancer risk and to evaluate the functional significance of UGT1A6 polymorphisms. Genomic DNA was isolated from leukocytes. Eight UGT1A6 polymorphisms were sequenced in a test set of 72 Chinese lung cancer patients and 62 healthy controls. Potential risk modifying alleles were validated in a separate set of 95 Chinese lung cancer patients and 100 healthy controls. UGT1A6 19T>G, 541A>G and 552A>C showed significant association with increased lung cancer risk, while UGT1A6 105C>T and IVS1+130G>T were significantly associated with reduced lung cancer risk. Multivariate logistic regression analysis demonstrated a significant association of lung cancer with UGT1A6 541A>G (OR: 3.582, 95% CI: 1.27–10.04, p = 0.015), 552A>C (OR: 5.364, 95% CI: 1.92–14.96, p = 0.001) and IVS1+130G>T (OR: 0.191, 95% CI: 0.09–0.36, p<0.001). Functional test demonstrated that UGT1A6 105C>T increased mRNA stability, providing a plausible explanation of its association with reduced lung cancer risk. Thus UGT1A6 polymorphisms may be used to identify people with increased risk of developing lung cancer.     

Comparative effects of trichothecene mycotoxins on bovine platelet function: Acetyl T-2 toxin,a more potent inhibitor than T-2 toxin

The effects of the trichothecene mycotoxins (acetyl T-2 toxin, T-2 toxin, HT-2 toxin, palmityl T-2 toxin, diacetoxyscirpenol (DAS), deoxynivalenol (DON), and T-2 tetraol) on bovine platelet function were examined in homologous plasma stimulated with platelet activating factor (PAF). The mycotoxins inhibited platelet function with the following order of potency: acetyl T-2 toxin > palmityl T-2 toxin = DAS > HT-2 toxin = T-2 toxin. While T-2 tetraol was completely ineffective as an inhibitor, DON exhibited minimal inhibitory activity at concentrations above 10×10^?4M. The stability of the platelet aggregates formed was significantly reduced in all mycotoxin treated platelets compared to that of the untreated PAF controls. It is suggested that the increased sensitivity of PAF stimulated bovine platelets to the more lipophilic mycotoxins may be related to their more efficient partitioning into the platelet membrane compared to the more hydrophilic compounds.     

Growth-promoting effects of lactoferrin on L. acidophilus and Bifidobacterium spp.

We investigated the effects of lactoferrin on the growth of L. acidophilus CH-2, Bifidobacterium breve ATCC 15700, B. longum ATCC 15707, B. infantis ATCC 15697, and B. bifidum ATCC 15696. The growth of L. acidophilus was stimulated by bovine holo-lactoferrin but not by apo-lactoferrin. With bifidobacteria, bovine lactoferrin stimulated growth of three strains: B. breve, B. infantis and B. bifidum under certain conditions. Both apoprotein and holoprotein had similar effects. However, B. longum growth was not affected by lactoferrin. Thus, the mechanism of stimulating growth of bifidobacteria may be different from that of L. acidophilus. By far-western blotting using biotinylated lactoferrin and horseradish peroxidase-conjugated streptavidin, lactoferrin-binding proteins were detected in the membrane protein fraction of L. acidophilus, B. bifidum, B. infantis and B. breve. The molecular weights of lactoferrin-binding proteins of L. acidophilus were estimated from SDS-polyacrylamide gel electrophoresis to be 27, 41 and 67 kDa, and those of the three bifidobacterial strains were estimated to be 67-69 kDa. However, no such lactoferrin-binding components were detected in the membrane fraction of B. longum. It is interesting that the appearance of lactoferrin-binding proteins in the membrane fraction of these species corresponds to their growth stimulation by lactoferrin.     

Physical mapping of the Mycoplasma gallisepticum S6 genome with localization of selected genes.

We report the construction of a physical map of the Mycoplasma gallisepticum S6 genome by field-inversion gel electrophoresis of DNA fragments generated by digestion of genomic DNA with rare-cutting restriction endonucleases. The size of the M. gallisepticum S6 genome was calculated to be approximately 1,054 kb. The loci of several genes have been assigned to the map by Southern hybridization utilizing specific gene probes.