N-Heterocyclic Carbene-Catalyzed Formal Intramolecular [3 + 2] Annulations of Cyclohexadienone-Tethered Ynals.

A formal [3 + 2] annulation of cyclohexadienone-tethered ynals is enabled by an N-heterocyclic carbene (NHC) catalyst, affording a tricyclo[6.2.1.04,11]undecane framework. This study represents the first demonstration of using C═C double bonds as the reaction partner in the NHC-catalyzed annulation of ynals. This strategy is characterized by mild reaction conditions and 100% atom economy as well as high catalytic performance and efficiency.

A Highly Enantioselective Homoenolate Michael Addition/Esterification Sequence of Cyclohexadienone-Tethered Enals via NHC Catalysis.

Reported here is a highly enantioselective homoenolate Michael addition/esterification sequence of cyclohexadienone-tethered enals via N-heterocyclic carbene (NHC) catalysis, affording the enantiopure cis-hydrobenzofurans, cis-hydroindoles, and cis-hydroindenes. The NHC catalyst bearing a nitro group greatly enhances the stereocontrol, and a bulky N-aryl substituent of the triazolium salt in the catalyst is helpful for inhibiting the further aldol condensation after homoenolate Michael addition. The utility of this protocol is highlighted by a gram-scale experiment and versatile downstream transformations.

Molecular epidemiology of hepatitis B virus genotypes and subgenotypes in ethnic minority populations, Yunnan province, China.

The aim of our study was to determine the distribution of hepatitis B virus (HBV) genotypes and subgenotypes in ethnic minorities in Yunnan province to provide evidence supporting the theoretical basis for hepatitis B prevention and control. We obtained serum samples and demographic data from 765 individuals reported by Yunnan province who had either acute or chronic HBV infection and were from one of 20 ethnic minority populations: Achang, Bai, Brown, Tibetan, Dai, Deang, Dulong, Hani, Hui, Jingpo, Lahu, Yi, Lisu Miao, Naxi, Nu, Pumi, Wa, Yao, or Zhuang people. We sequenced the HBV DNA and determined the genotypes and subgenotypes of the isolated HBVs. We mapped the genotype and subgenotype distribution by ethnic minority population and conducted descriptive analyses. There were four genotypes among the 20 ethnic groups: genotype B (21.3% of samples), C (76.6%), D (1.8%) and I (0.3%). The most common subgenotype was C1. There were no genotype differences by gender (P = 0.954) or age (P = 0.274), but there were differences by region (P < 0.001). There were differences in genotype distribution (P < 0.001) and subgenotype distribution (P = 0.011) by ethnic group. Genotype D was most prominent in Tibet and most HBV isolates were C/D recombinant viruses. The only two genotype I virus isolates were in Zhuang people. Susceptibility and geographic patterns may influence HBV prevalence in different ethnic populations, but additional research is needed for such a determination.

A Ratiometric and Colorimetric Hemicyanine Fluorescent Probe for Detection of SO2 Derivatives and Its Applications in Bioimaging.

Based upon the intramolecular charge transfer (ICT) mechanism, a novel ratiometric fluorescent probe EB was developed to detect SO32-/HSO3-. The probe displayed both colorimetric and ratiometric responses toward SO32-/HSO3-. It displayed a quick response (within 60 s), good selectivity and high sensitivity (a detection limit of 28 nM) towards SO32-/HSO3-. The SO32-/HSO3- sensing mechanism was confirmed as the Michael addition reaction by ESI-MS. Moreover, the probe could be applied to measure the level of sulfite in real samples, like sugar and chrysanthemum, and it could also be used to detect SO32-/HSO3- in HepG2 cells through confocal fluorescence microscopy, which proved its practical application in clinical diagnosis.

[Distribution of hepatitis B virus genotypes and serotypes in people who had a physical examination in Yunnan Province].

OBJECTIVE: To know genotypes and serotypes of hepatitis B virus (HBV) detected from hepatitis B infected people in Yunnan Province. METHODS: Serum samples were collected from HBsAg carriers detected from people who had a physical examination at Yunnan Provincial Center for Disease Control and Prevention. The S genes of HBV were amplified by nested PCR and the PCR products were sequenced. The viral genotype was identified by phylogenetic analysis. 27 reference sequences corresponding to HBV genotype A to I were obtained from GenBank. According to the amino acid sequences deduced from the nucleotide sequences of S gene, the dominant serotype of HBV detected from these people were confirmed. RESULTS: 39 HBsAg positive serum samples were detected from 2216 people who had a physical examination. The results shows that 76.9% were C genotype; 15.4% were B genotype; 5.1% were D genotype; 2.5% were I genotype. Three serotypes were found. The rates of adw2, adrq+ and ayr serotypes are 71.8%, 17.9% and 10.3% respectively. All of adw2 subtype specimens are C genotype. Among the serum specimens in which both HBsAg and HBeAg are positive, 75% were C genotype and adw2 subtype. CONCLUSION: It is determined that the main genotype and subtype of HBV prevailed in Yunnan province is C genotype and adw2 subtype.

[Molecular identification of hepatitis B virus genotype I in Yunnan Province, the People's Republic of China].

Molecular typing was conducted according to the reported method for one HBsAg positive carrier who had a physical examination in Yunnan Province. The S gene of this HBV sample was amplified by nested PCR and the PCR products were directly sequenced. Blast searching was done on the Genbank database and the sequence were compared with the HBV reference sequences in database. The phylogenetic tree was constructed. Homology analysis of nucleotide and smino acid were performed between the sequences from the sample and the reference sequences corresponding to HBV genotype A to I. Analysis of nucleotide and amino acid identities suggested that the sample belonged to HBV genotype I. The HBV genotype I is the first reported in China.

[Investigation on one vaccine-derived poliovirus (VDPV) case in Yunnan Province].

To find out epidemiological feature of paralytic cases caused by type 2 vaccine-derived poliovirus (VDPV) and the excretion status of the case and to explore the enterovirus infection status among healthy children under five years old around the case in Zhaotong city, Yunnan Province in 2010. Field epidemiological studies at the epidemic area were conducted and a total of 108 stool samples were collected, three from the case, seven from the close contacts and 98 from the healthy children. VDPV was not isolated again from the case; Sabin-like PV strains or VDPV were not isolated from the close contacts and the healthy children; An active search for acute flaccid paralysis cases was conducted in the area, which indicated that the VDPV did not cause virus circulation in local area. Twenty one (20.0%) NPEVs were isolated from 105 stool samples. Among the 21 NPEV isolates, 11 isolates (52.4%) were HEV-A (3 serotypes), 10 isolates (47.6%) were HEV-B (4 serotypes).

Effects of Antrodia camphorata on alcohol clearance and antifibrosis in livers of rats continuously fed alcohol.

Alcoholic fatty liver disease (AFLD) is the result of an excessive or chronic consumption of alcohol. Nine male Wistar rats per group were randomly assigned to one of the following drinking treatments: a 20% (w/w) alcohol solution (ALC); a 20% (w/w) alcohol solution cotreated with 0.25 g silymarin/kg BW/day; or a 20% (w/w) alcohol solution cotreated with 0.025 g Niuchangchih ( Antrodia camphorata )/kg BW/day for 4 weeks. Rats with cotreatments of silymarin or Niuchangchih had smaller (p < 0.05) relative liver size, less (p < 0.05) liver lipid accumulation, and lower (p < 0.05) liver damage indices [aspartate aminotransferase (AST) and alkaline phosphatase (ALP) values]. In the regulation of alcohol metabolism, the lower serum alcohol level was observed only in alcohol-fed rats supplemented with Niuchangchih. Meanwhile, cotreatment of silymarin or Niuchangchih increased (p < 0.05) CAT and ALDH activities but did not (p > 0.05) affect ADH and CYP2E1 expressions, which accelerate alcohol metabolism in the body. Additionally, neither silymarin nor Niuchangchih (p > 0.05) influenced serum/hepatic MMP-2 activities and NF-κB, AP1, and α-SMA gene expressions, but serum/hepatic MMP-9 activities and TNF-α, KLF-6, and TGF-ß1 gene expressions of alcohol-fed rats were down-regulated (p < 0.05) by silymarin or Niuchangchih, which also could explain the lower liver damage observed in rats chronically fed alcohol.

Fruiting body of Niuchangchih (Antrodia camphorata) protects livers against chronic alcohol consumption damage.

An alcoholic fatty liver disease was induced by drinking water containing 20% (w/w) alcohol. Therapeutic groups were orally administrated dosages of 0.25 g silymarin/kg body weight (BW) and a low dosage of Niuchangchih (Antrodia camphorata) (0.025 g/kg BW) and a high dosage of Niuchangchih (0.1 g/kg BW) per day. Niuchangchih, especially at the high dosage, not only showed a hypercholesterolemic effect (p < 0.05) but also reduced (p < 0.05) hepatic lipids in alcohol-fed rats. Those beneficial effects could be partially attributed to higher (p < 0.05) fecal cholesterol and bile acid outputs, as well as downregulations (p < 0.05) of 3-hydroxy-3-methylglutaryl-CoA reductase, sterol regulatory element-binding protein-1c, acetyl-CoA carboxylase, fatty acid synthase, and malic enzyme gene expressions; meanwhile, there was an upregulation of low-density lipoprotein receptor and peroxisome proliferator-activated alpha gene expression. Besides, Niuchangchih also enhanced (p < 0.05) the liver glutathione, Trolox equivalent antioxidant capacity, and activities of superoxide dismutase, catalase, and glutathione peroxidase and decreased the liver malondialdehyde content, which also partially contributed to the lowered (p < 0.05) serum aspartate aminotransferase levels and no observed lesion in the histological examination of alcohol-fed rats.