Quinolones are broad-spectrum antibacterial agents used in human and veterinary medicine, and their extensive use have been associated with a rise of the quinolone resistance. In the present study, the quinolone resistance of avian E.coli and Salmonella isolates was evaluated and compared, in which 344 avian E.coli and 224 Salmonella isolates from 1990s were serogrouped with antisera and thc antimicrobial susceptibility test to 10 quinolones was carried out by using the Kirby-Bauer method recommended by Clinical and Laboratory Standards Institute (CLSI). It was demonstrated that the 344 isolates of avian E.coli distributed in 27 serogroups and 68.90% (237/344) of the isolates belonged to four O-serogroups: i.e. O1, O2, O18, O78, and the 224 isolates of avian Salmonella were all determined to be Salmonella pullorum. The drug-resistance rate of avian E. coli isolates to nalicixic acid from 1993-1999 was more than 60%(64.43%,131/181), whereas those of isolates to 9 antibiotics from 2000-2008 had a drug-resistance rates of more than 60%, namely,nalicixic acid(92.02%), fleroxacin(79.75%), pipemidic acid(79.14%), enrofloxacin(78.53%), enoxacin(76.07%), lomenfloxacin(74.85%), ciprofloxacin(69.33%), norfloxacin(63.80%) and ofloxacin(61.35%). For the 4 O-serogroups of the avian E.coli isolates, the drug-resistance rates of more than 50% to antimicrobials were as follows: O78 isolates to 7 antimicrobials;O18 isolates to 5 antimicrobials, and O1 and O2 isolates just to 3 antimicrobials. The quinolone resistance of Salmonella isolates was much lower than E.coli, in which 101 salmonella isolates from 1993-1999 were all susceptible to quinolones. Nalicixic acid resistance of salmonella isolate firstly appeared in 2000, and the drug-resistance rate of salmonella isolates from 2000-2008 was found to be more than 60% for nalicixic acid(83.74%), but those to other quinolones were comparatively lower. These results indicated that the quinolone resistance of avian E.coli and salmonella were increasing in the past two decads because of the over-use of antibiotics.

Objective To investigate the association between plasma homocysteine (Hcy) levels and cystathionineβsynthase (CBS) T833C gene polymorphism with essential hypertension in Xinjiang Kazakh and Han populations. Methods A total of 239 Kazak patients with hypertension (Kazak EH group), 206 Kazak people with normal blood pressure (Kazak con?trol group), 256 Han patients with hypertension (Han EH group) and 206 Han people with normal blood pressure (Han con?trol group) were selected for the study. Amplification refractory mutation system(ARMS) was used to analyze the polymor?phism of CBS gene T833C,TT,TC and CC genotypes and the various sites of T,C allele frequencies in four groups. In the meantime, the Hcy level and related biochemical indices were detected using automatic biochemical analyzer. Results The plasma Hcy levels were significantly higher in Kazak EH group and Han EH group than those of Kazak control group and Han control group (P<0.05). The C allele frequencies were significantly higher in Kazak EH group than that of Kazak control group (P<0.05). The plasma level of Hcy was significantly lower in Kazakh and Han people with TT genotypes than that of TC genotypes (P<0.05). There were no significant differences in the frequency of genotypes and alleles between Han EH group and Han control group (P>0.05).Conclusion The Cystathionineβsynthase gene of T833C polymorphism may be associated with essential hypertension in Kazak people in Xinjiang, but no such association in Han population in Xinji?ang. The mechanism may be related to the altered metabolism of Hcy induced by CBS mutation.

Objective: To explore the influences of pulchinenoside on the proliferation and migration of oral squamous cell carcino-ma cells and the expression of calpain 1 ( calpain 1). Methods: The human oral squamous cell carcinoma CAL27 cells were treated with pulchinenoside at the concentrations of 0, 1. 0,2. 0, 4. 0, 8. 0, 12. 0 mg·L-1. MTT method was used to detect the effect of pul-chinenoside on the proliferation of CAL27 cells; the effects of pulchinenoside on the proliferation and migration of CAL27 cells were de-tected by cell scratch test and Transwell experiment; the expression changes of calpain 1, E-cadherin and N-cadherin protein in CAL27 cells were detected by Western blot. Results: MTT results showed that, compared with the control group, the inhibitory rate of pul-chinenoside for the proliferation of CAL27 cells increased significantly (P<0. 05) in a time- and dose-dependent manner. The light microscope results showed that the CAL27 cells morphology changed from the long spindle shape to the cobblestone like epithelioid after the 48-hour treatment with 12. 0 mg·L-1pulchinenoside. Cell scratch test results showed that with the increase of pulchinenoside con-centration, the CAL27 cell migration ability gradually weakened. Transwell experimental results show that with the increase of pul-chinenoside concentration, the CAL27 cell migration and invasion abilities decreased gradually (P <0.05). Western blot results showed that with the increase of the concentration of pulchinenoside, the expression levels of calpain 1 and N-cadherin protein in CAL27 cells decreased gradually (P<0. 05), the expression level of E-cadherin protein increased gradually (P>0. 05). Conclusion:Pulchinenoside can inhibit the proliferation, migration and invasion of oral squamous cell carcinoma CAL27 cells, and its mechanism may be related to the down-regulation of calpain 1 and N-cadherin expressions and up-regulation of E-cadherin expression.

A new coronavirus (SARS-CoV-2) has been identified as the etiologic agent for the COVID-19 outbreak. Currently, effective treatment options remain very limited for this disease; therefore, there is an urgent need to identify new anti-COVID-19 agents. In this study, we screened over 6,000 compounds that included approved drugs, drug candidates in clinical trials, and pharmacologically active compounds to identify leads that target the SARS-CoV-2 papain-like protease (PLpro). Together with main protease (M
Antiviral Agents/therapeutic use* ; Binding Sites ; COVID-19/virology* ; Coronavirus Papain-Like Proteases/metabolism* ; Crystallography, X-Ray ; Drug Evaluation, Preclinical ; Drug Repositioning ; High-Throughput Screening Assays/methods* ; Humans ; Imidazoles/therapeutic use* ; Inhibitory Concentration 50 ; Molecular Dynamics Simulation ; Mutagenesis, Site-Directed ; Naphthoquinones/therapeutic use* ; Protease Inhibitors/therapeutic use* ; Protein Structure, Tertiary ; Recombinant Proteins/isolation & purification* ; SARS-CoV-2/isolation & purification*