Genetic variations in the bitter taste receptor gene TAS2R38 are related to cigarette smoking behavior in Han Chinese smokers.

BACKGROUND: Smoking behavior is influenced by multiple genes, including the bitter taste gene TAS2R38. It has been reported that the correlation between TAS2R38 and smoking behavior has ethnicity-based differences. However, the TAS2R38 status in Chinese smokers is still unclear. OBJECTIVE: This study aims to investigate the possible relationship between genetic variations in TAS2R38 (A49P, V262A and I296V) and smoking behaviors in the Han Chinese population. METHODS: The haplotype analyses were performed and smoking behavior questionnaire was completed by 1271 individuals. Genetic association analyses for smoking behavior were analyzed using chi-square test. Further, for investigating the molecular mechanism of TAS2R38 variants effect on smoking behavior, we conducted TAS2R38-PAV and TAS2R38-AVI expression plasmids and tested the cellular calcium assay by cigarette smoke compounds stimulus in HEK293. RESULTS: Significant associations of genetic variants within TAS2R38 were identified with smoking behavior. We found a higher PAV/PAV frequency than AVI/AVI in moderate and high nicotine dependence (FTND ≥ 4; X2 = 4.611, 1 df, p = 0.032) and strong cigarette smoke flavor intensity preference (X2 = 4.5383, 1 df, p = 0.033) in participants. Furthermore, in the in vitro cellular calcium assay, total particle matter (TPM), N-formylnornicotine and cotinine, existing in cigarette smoke, activated TAS2R38-PAV but not TAS2R38-AVI-transfected cells. CONCLUSION: Our data highlights that genetic variations in TAS2R38 are related to smoking behavior, especially nicotine dependence and cigarette smoke flavor intensity preference. Our findings may encourage further consideration of the taste process to identify individuals susceptible to nicotine dependence, particularly Han Chinese smokers.

Xanthones from the herb of Swertia elata and their anti-TMV activity.

Two new xanthones (1-2), together with four known ones (3-6), were isolated from whole herb of Swertia elata. Their structures were elucidated by spectroscopic methods including extensive 1D- and 2D-NMR techniques. Their anti-tobacco mosaic virus (anti-TMV) activity test revealed that 1-6 showed weak anti-TMV activities with inhibition rate in the range of 15.2-28.8% at the concentration of 20 µM.

Lysinibacillus tabacifolii sp. nov., a novel endophytic bacterium isolated from Nicotiana tabacum leaves.

A Gram-positive, catalase- and oxidase-positive, strictly aerobic, endospore-forming rod bacterium, designated K3514(T), was isolated from the leaves of Nicotiana tabacum. The strain was able to grow at temperatures of 8-40°C, pH 5.0-10.0 and NaCl concentrations of 0-7%. The predominant quinones (>30%) of this strain were MK-7(H2) and MK-7. Phylogenetic analysis of 16S rRNA gene sequence showed that strain K3514(T) was affiliated to the genus Lysinibacillus, with its closest relatives being Lysinibacillus mangiferihumi (98.3% sequence similarity), Lysinibacillus sphaericus (97.9% sequence similarity), Lysinibacillus fusiformis (97.4% sequence similarity), and Lysinibacillus xylanilyticus (97.3% sequence similarity). However, low levels of DNA-DNA relatedness values suggested that the isolate was distinct from the other closest Lysinibacillus species. Additionally, based on analysis of morphological, physiological, and biochemical characteristics, the isolate could be differentiated from the closest known relatives. Therefore, based on polyphasic taxonomic data, the novel isolate likely represents a novel species, for which the name Lysinibacillus tabacifolii sp. nov. and the type strain K3514(T) (=KCTC 33042(T) =CCTCC AB 2012050(T)) are proposed.

Preventive effects of autologous bone marrow mononuclear cell implantation on intrahepatic ischemic-type biliary lesion in rabbits.

BACKGROUND: The ischemic-type biliary lesion (ITBL) is one of the most serious biliary complications of liver transplantation. This study aimed to investigate the effects of autologous bone marrow mononuclear cell (BM-MNC) implantation on neovascularization and the prevention of intrahepatic ITBL in a rabbit model. METHODS: The rabbits were divided into control, experimental model, and cell implantation groups, with 10 in each group. The model of intrahepatic ITBL was established by clamping the hepatic artery and common bile duct. Autologous BM-MNCs were isolated from the tibial plateau by density gradient centrifugation and were implanted through the common hepatic artery. Changes in such biochemical markers as aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, gamma-glutamyltranspeptidase, total bilirubin and direct bilirubin were measured. Four weeks after operation, cholangiography, histopathological manifestations, differentiation of BM-MNCs, microvessel density and the expression of vascular endothelial growth factor were assessed. RESULTS: Compared with the experimental model group, the BM-MNC implantation group showed superiority in the time to recover normal biochemistry. The microvessel density and vascular endothelial growth factor expression of the implantation group were significantly higher than those of the control and experimental model groups. The ITBL in the experimental model group was more severe than that in the implantation group and fewer new capillary blood vessels occurred around it. CONCLUSIONS: Implanted autologous BM-MNCs can differentiate into vascular endothelial cells, promote neovascularization and improve the blood supply to the ischemic bile duct, and this provides a new way to diminish or prevent intrahepatic ITBL after liver transplantation.