[Molecular characteristics of ciprofloxacin-cefotaxime-azithromycin co-resistant Salmonella enterica Serovar Thompson in foodborne diseases in Hunan Province].

Objective: To investigate the molecular characteristics of ciprofloxacin-cefotaxime-azithromycin co-resistant Salmonella enterica serovar Thompson (S. Thompson) isolates from sporadic cases of foodborne diseases and aquatic foods in Hunan province. Methods: Ciprofloxacin-cefotaxime-azithromycin co-resistant S. Thompson isolates were selected from samples, and broth microdilution method was used to determine the resistance to 11 antibiotics of these isolates in vitro. Whole genome sequencing was used for investigating antimicrobial resistance gene patterns and phylogenetic relationships of strains. Results: Nine ciprofloxacin-cefotaxime-azithromycin co-resistant isolates were recovered from 19 S. Thompson isolates. Among nine ciprofloxacin-cefotaxime-azithromycin co-resistant isolates, eight of them harbored IncC plasmids, simultaneously carrying plasmid-mediated quinolone resistance (PMQR) genes qepA and qnrS1, ß-lactamase resistance gene blaCMY-2, azithromycin resistance gene mph(A), and one isolate harbored IncR plasmid, and carried PMQR genes qnrB4 and aac(6')-Ib-cr, blaOXA-10 and mph(A). Genetic environment analysis showed that qnrS1, qepA, mph(A) and blaCMY-2 genes might be integrated on genomes of strains by ISKra4, IS91, IS6100 and ISEcp1, respectively. Phylogenetic core genome comparisons demonstrated that ciprofloxacin-cefotaxime-azithromycin co-resistant isolates from patients and aquatic foods were genetically similar and clustered together. Conclusion: Ciprofloxacin-cefotaxime-azithromycin co-resistant S. Thompson isolates have been isolated from both human and aquatic food samples, suggesting that the spread of multidrug resistant Salmonella between human and aquatic animals.

[Epidemiological and virus molecular characterization of dengue fever outbreak in Hunan province, 2018].

Objective: To analyze the epidemiological and etiological characteristics of a dengue fever outbreak in Hunan province in 2018. Methods: Real-time PCR assay was performed for the laboratory diagnosis of 8 suspected dengue fever cases. Etiological surveillance was performed in 186 suspected dengue fever cases and fever cases who had close contacts with dengue fever patients. C6/36 cells was used for the virus isolation from acute phase serum. By sequencing the full length of E genes of 15 dengue virus strains, phylogenetic analysis was performed based on the sequences obtained, including reference sequences from the NCBI GenBank database, the serotypes and gene subtypes of the virus were analyzed to trace the possible source of transmission. An emergency monitoring of vector density and a retrospective survey of sero-epidemiology in healthy population were conducted in the epidemic area. Results: In the serum samples of 8 suspected patients, 6 were dengue virus RNA positive, and 4 were NS1 antigen positive. In 186 suspected patients, 96 were dengue virus nucleic acid, NS1 antigen or antibody positive in etiological test. A total of 64 dengue virus strains were isolated. The phylogenetic analysis showed that all the dengue virus strains belonged to type 2, which might be from Guangdong or Zhejiang provinces. The Bretub index was up to 65, indicating an extremely high risk of transmission. The positive rate of the dengue virus IgG antibody was 0.53%(2/377) in retrospective survey of 377 healthy people. Conclusion: The field epidemiologic and the molecular genetics analyses showed the outbreak of dengue fever in Hunan in 2018 was caused by imported cases and dengue virus 2.

[Characteristics and diversity of infectious diarrheal caused by various pathogens].

Objective: To understand the characteristics and differences of diarrhea-related symptoms caused by different pathogens, and the clinical features of various pathogens causing diarrhea. Methods: Etiology surveillance program was conducted among 20 provinces of China from 2010 to 2016. The acute diarrhea outpatients were collected from clinics or hospitals. A questionnaire was used to survey demographics and clinical features. VFeces samples were taken for laboratory detection of 22 common diarrhea pathogens, to detect and analyze the clinical symptom pattern characteristics of the patient's. Results: A total of 38 950 outpatients were enrolled from 20 provinces of China. The positive rates of Rotavirus and Norovirus were the highest among the five diarrhea-causing viruses (Rotavirus: 18.29%, Norovirus: 13.06%). In the isolation and culture of 17 diarrhea-causing bacterial, Escherichia coli showed the highest positive rates (6.25%). The clinical features of bacterial diarrhea and viral diarrhea were mainly reflected in the results of fecal traits and routine examination, but pathogenic Vibrio infection was similar to viral diarrhea. Conclusion: Infectious diarrhea presents different characteristics due to various symptoms which can provide a basis for clinical diagnosis.

[Epidemiology of human brucellosis and source of Brucella isolates in Hunan province].

Objective: To analyze the epidemiological characteristics of human brucellosis and trace back source of infection of human brucellosis in Hunan province during 2010-2018, and provide evidence for the prevention and control of human brucellosis. Methods: The surveillance data of human brucellosis in Hunan during 2010-2018 were analyzed with software Excel 2016 and ArcGIS 10.5, the epidemic characteristics were described using cases number, constituent ratio and rate. The conventional biotype methods were used for the identification of Brucella species, UTS-PCR was applied to further confirm the results from conventional biotype detections, then six virulence genes of two clinical Brucella strains were detected by PCR assay. Cluster analysis of two Brucella strains were performed with Multiple locus variable-number tandem repeat analysis (MLVA) for the investigation of the infection source of human brucellosis. Results: From 2010 to 2018, a total of 728 human brucellosis cases were reported in Hunan with the annual incidence rate of 0.12/100 000. The incidence rate was 2.50/100 000 in Chenzhou and 1.90/100 000 in Yongzhou, higher than those in other areas. The number of counties reporting cases increased from 5 in 2010 to 69 in 2018. Most cases were reported in age group 45-54 years, accounting for 38.32% (279/728). The cases in farmers accounted for 59.07% (430/728) of the total. The male to female ratio of the cases was 2.75 ∶ 1. The reported case number was highest during May-July, accounting for 45.33% (330/728). The incidence was high in summer and autumn, and the peak was in May. The conventional identification showed that two strains were all Brucella melitensis biovar 1, consistent with UTS-PCR amplification results. Six virulence genes were found in two isolated strains, suggesting that the Brucella melitensis strains in this study had strong virulence. MLVA results confirmed that two strains detected in Hunan had complete identical MLVA-16 genotype with strains isolated from goat and camel in Inner Mongolia Autonomous Region, indicating that there was molecular epidemiology relationship between these strains and the source of infection were originated from Inner Mongolia. Conclusions: The epidemic of human brucellosis in Hunan is becoming serious, and disease has spread to general population and non-epidemic areas. Two Brucella melitensis strains detected in Hunan were originated from Inner Mongolia. The quarantine and inspection in animal transportation should be strengthened to prevent human outbreaks of brucellosis.

Over-expression of MEOX2 promotes apoptosis through inhibiting the PI3K/Akt pathway in laryngeal cancer cells.

The early-stage diagnosis and treatment for the recurrence of larynx carcinoma needs further investigation. Mesenchyme homeobox 2 (MEOX2) was speculated as a novel suppressor gene in larynx carcinoma in our study, the molecular mechanism was studied. Real-time quantitative PCR (RT-qPCR) and Western blot were used to detect mRNA and protein levels of MEOX2 in laryngeal cancer tissues and cells (Hep-2, TU212, AMC-NH-8 and TU686 cells), and also apoptosis and phosphoinositide 3-kinase (PI3K)/protein kinase (Akt) related factors in TU212 cells transfected with MEOX2. Cell counting kit-8 (CCK8) assay and Annexin-Ⅴ/PI staining assay were conducted to determine cell viability and apoptosis rates respectively.46 patients with larynx carcinoma were involved in this study. The expression of MEOX2 was lower in larynx carcinoma tissues than normal tissues, correlated with clinical stages, differentiated degrees, and survival times. The expression of MEOX2 was the lowest among those laryngeal cancer cells, and was chosen to be transfected with MEOX2 in the following study. Over-expression of MEOX2 inhibited cell viability and promoted apoptosis of TU212 cells, via increasing the expression levels of Caspase-3, and decreasing levels of C-Myc, XIAP, PI3K p110α, PI3K p110ß, PI3K class III and p-Akt. In summary, the expression levels of MEOX2 were inhibited in larynx carcinoma than normal tissues, correlated with the progression of the cancer. Over-expression of MEOX2 in laryngeal cancer cells inhibited cell viability and promoted apoptosis, via regulating apoptosis and PI3K/Akt pathway related factors. It would provide evidence for MEOX2 to be used as a therapeutical gene in larynx carcinoma.

Development-promoting effect of chicken embryo membrane on chicken ovarian cortical pieces of different age.

Ovarian cortical tissues of various ages of chicken were grafted underneath chorioallantoic membrane (CAM) of 6-d-old chicken embryo and the grafts were collected on d 0, 2, 4, 8, or 10. The tissue sections were prepared to examine the development of follicles in grafts and the proliferative ability of follicles was examined by immunohistochemistry analysis of proliferating cell nuclear antigen. The results indicated that the development of follicles in cultured chicken ovarian cortical pieces progressed smoothly and slowly similar to those in vivo, and the environment of chicken embryo was more suitable for the synchronous development of oocyte and follicular cells in the larger follicles. Meanwhile, the synchronous development could be more easily achieved in the chicken ovarian tissues of 12- to 15-wk chicken. Neither oocyte nor granulosa cells but the thecal cells of follicles developed in grafts of 13- to 15-d chicken within 10 d of culturing in ovo, and the CAM can ease follicular atresia in chicken ovarian grafts of 12- to 15-wk chicken. The proliferative performance of follicles in the grafts was not influenced by the environment of chicken embryo. These results indicated that the chicken embryo has the ability to support slow development of primordial and primary follicles in grafted ovarian cortical tissues of chickens of different ages. The CAM system may also prove useful for the study of early follicle development with further information.

Cytochrome P450 2E1 genetic polymorphism and gastric cancer in Changle, Fujian Province.

AIM: Genetic polymorphism in enzymes of carcinogen metabolism has been found to have the influence on the susceptibility to cancer. Cytochrome P450 2E1 (CYP2E1) is considered to play an important role in the metabolic activation of procarcinogens such as N-nitrosoamines and low molecular weight organic compounds. The purpose of this study is to determine whether CYP450 2E1 polymorphisms are associated with risks of gastric cancer. METHODS: We conducted a population based case-control study in Changle county, Fujian Province, a high-risk region of gastric cancer in China. Ninety-one incident gastric cancer patients and ninety-four healthy controls were included in our study. Datas including demographic characteristics, diet intake, and alcohol and tobacco consumption of individuals in our study were completed by a standardized questionnaire.PCR-RFLP revealed three genotypes:heterozygote (C1/C2) and two homozygotes (C1/C1 and C2/C2) in CYP2E1. RESULTS: The frequency of variant genotypes (C1/C2 and C2/C2) in gastric cancer cases and controls was 36.3% and 24.5%, respectively. The rare homozygous C2/C2 genotype was found in 6 individuals in gastric cancer group(6.6%), whereas there was only one in the control group (1.1%). However, there was no statistically significant difference between the two groups (two-tailed Fisher's exact test P=0.066). Individuals in gastric cancer group were more likely to carry genotype C1/C2 (odds ratio, OR=1.50) and C2/C2 (OR=7.34) than individuals in control group (chi(2) =4.597, for trend P=0.032). The frequencies of genotypes with the C2 allele (C1/C2 and C2/C2 genotypes) were compared with those of genotypes without C2 allele (C1/C1 genotype) among individuals in gastric cancer group and control group according to the pattern of gastric cancer risk factors. The results show that individuals who exposed to these gastric cancer risk factors and carry the C2 allele seemed to have a higher risk of developing gastric cancer. CONCLUSION: Polymorphism of CYP2E1 gene may have some effect in the development of gastric cancer in Changle county, Fujian Province.

A neuron model based on brain biochemical principles.

The electrical activity and excitation of the brain is based on certain biochemical processes, particularly, the activity of transmitter-receptor-ion channel system and the DNA-RNA-Pr (Pr:protein) system. There have already been some neuron models relating to the ion channel, but the kinds and numbers of transmitters, receptors, and ion channels are directly or indirectly conditioned by the DNA-RNA-Pr system. To reflect these facts, we present a new neuron model based on the important biochemical chains of the brain. This model is applied to both the simulation research of electrical activity and the information processing function of the brain. In this demonstration, we will introduce: 1) How to express the connection between the neuron excitation and the transmitter-receptor-ion channel system; 2) How to express the connection between the transmitter-receptor-ion channel system of neuron and the DNA-RNA-Pr system; 3) How to express the connection among 16,000 artificial neurons on the basis of the above-mentioned points; 4) The time and the state of the excitation passing through a particular neuron in a group of neurons.