Objective To study the association of multi-drug resistance with mutations in mar gene in clinical isolates of Shigella.Methods Fifty-four clinical isolates of Shigella were collected.Susceptibility tests of tetracycline(TE),chloramphenieol(C),ampicillin(AM),cipr ofloxacin(CIP),and norfloxacin(NOR)were performed in a11 isolates.Hexane and cyclohexane were used to study the organic solvent tolerance of all clinical isolates.marOR genes of these strains were analyzed by potymerase chain reaction-single strand conformation polymorphism(PCR-SSCP)and were sequenced. Results Thirty-five multi-drug resistant strains were identified,and the rate of multi-drug resistance was 64.8%.Thirty-eight of 54 strains were tolerant to organic solvent,including 33 multi-drug resistance strains,3 drug resistant strains and 2 sensitive strains. marOR gene was found in all strains by PCR, and 5 multi-drug resistant strains,(14.29%)carrying marOR gene mutations in multi-drug resistant strains were found by SSCP analysis.DNA sequence analysis of marOR gene revealed that there was a 4 base deletion from base 1376 to 1379 in marO gene that resulted in frame-shift mutation.However,this deletion mutation didn;t exist in the standard strain S51250 and sensitive strains.There were 10 point mutations of marR gene in multi-drug resistant strains,2 of them resulting in amino acid changes:1752(G→A)Gly→ser,1854(T→c)Tyr→His.The rest mutations were all nonsense,and some of them occurred in sensitive strains or in many other strains.Conclusion The marO gene mutation may play an important role in the regulation of multi-drug resistance in Shigella spp.

Objective To determine the therapeutic effect of recombined rat insulin-like growth factory 1 gene and transforming growth factor beta-1(TGF-?_1)gene on anterior cruciate ligament transection(ACLT)- induced osteoarthritis-like changes in NZW rabbit knee joints.Methods Eighteen NZW rabbits were divided into 3 groups randomly after osteoanhritis was established by ACLT and another six rabbits were used as normal control group(group 1).Chondrocytes which had been transfected with IGF-1 gene,co-transfected with TGF-?_1 and IGF-1 gene(group 3,4)were injected into the rabbits knee joints.Experimental control group(group 2)only had ACLT bul was not transfected.After 4,8 weeks,rabbits were sacrificed and their joints were evaluated by morphological grades,histological examination,in situ hybridization examination,immunohistochemistry exami- nation,and transmission electron microscopy examination(TEM).Results The morphological grades showed that the normal control group had a very significant difference with the experimental control group(P

Objective:To investigate the prevalence and influencing factors of amnestic mild cognitive impairment of rural elderly in Guizhou province, which aims to provide scientific basis for the prevention and control of cognitive impairment in the elderly.Methods:Adopting a multi-stage cluster sampling method, a total of 1 535 rural Han and Bouyei elderly people aged 60 and above were selected from Guiyang city and Qiannan prefecture in Guizhou province as the survey subjects for the current situation survey, including demographic sociological characteristics, such as social was utilized behavior, social behavior disease history, height and weight and so on.Mini-mental state examination was utilized to measure cognitive function and SPSS 26.0 statistical software was used to perform χ 2 inspection and multivariate unconditional Logistics regression analysis to calculate odds ratio ( OR) and 95% confidence interval (95% CI). Results:A total of 242 elderly patients with aMCI were detected (15.8%). The results of univariate analysis showed that ethnicity(χ 2=4.333, P<0.05), gender(χ 2=18.367, P<0.01), marital status(χ 2=9.721, P<0.01), occupation(χ 2=7.786, P<0.01), annual family income(χ 2=28.085, P<0.01), current smoking(χ 2=11.873, P<0.01), specific hobbies(χ 2=25.968, P<0.01), physical exercise(χ 2=11.871, P<0.01), living style(χ 2=13.190, P<0.01), and activity participation(χ 2=13.004, P<0.01) all had an impact on aMCI. Multivariate Logistic regression analysis showed that Bouyei nationality( P<0.05, β=0.288, OR=1.333, 95% CI=1.002-1.775) and the women( P<0.05, β=0.516, OR=1.676, 95% CI=1.233-2.278)were risk factors for aMCI, and high annual family income( P<0.05, β=-0.839, OR=0.432, 95% CI=0.308-0.606), specific hobbies( P<0.05, β=-0.580, OR=0.560, 95% CI= 0.394-0.795), physical exercise( P<0.05, β=-0.410, OR=0.664, 95% CI=0.493-0.894), participation in activities( P<0.05, β=-0.424, OR=0.654, 95% CI=0.488-0.877), and non-living alone( P<0.05, β=-0.563, OR=0.569, 95% CI= 0.374-0.866) were the protective factors.Comparison of the prevalence of the disease between the Han and Bouyei nationalities, the detection rate of aMCI for the Bouyei elderly (18.0%) was higher than that of the Han (14.1%) (χ 2=4.333, P<0.05). After stratification according to gender, family annual income, specific hobbies, physical exercise, participation in activities and living style, the detection rate of elderly female subjects of Bouyei nationality was higher than that of Han nationality, whose difference was statistically significant (χ 2=5.562, P<0.05). The detection rate of Bouyei elderly was higher than that of Han when the annual household income was less than 30 000, and the difference was statistically significant (χ 2=8.570, P<0.01). Conclusion:The incidence of aMCI among the elderly of Bouyei nationality is higher, and the incidence of aMCI among females is higher than that of males, which should be paid more attention to.It is of vital importance to strengthen health education and publicity, guide the formation of knowledge-belief-behavior health-related behavior patterns, so as to improve the quality of life and reduce the risk of cognitive impairment.

Objective To investigate the expression of transforming growth factor β1,transforming growth factor beta receptor(TBR)Ⅰ,TβR Ⅱ,Smad4 and C-Jun in rats with nonalcoholic fatty liver disease(NAFLD)and to find out the mechanisms of liver fibrosis in patients with NAFLD.Methods A total of 18 male SD rats were randomly divided into normal control group(n=9)and model group(n=9).The rats in control group were fed with normal diet,and those in model group were fed with fat-rich diet(consisted of 10%lard oil+2%cholesterol).An rats were sacrificed at the 20th week.The levels of TGFβ1,TβR Ⅰ and TβR Ⅱ mRNA were examined by RT-PCR.The expressions of TGFβ1 and Smad4 in liver tissue were detected by immunohistochemistry.The expression of C-Jun protein was detected by Western blotting.Results The NAFLD model was successfully established.The immunohistochemistry examination revealed that TGFβ1 and Smad4 were expressed weekly in control group,but strongly expressed in model group.RT-PCR showed that A values of TGFβ1,TβR Ⅰ and TβR Ⅱ mRNA were 0.46±0.12,5.z4±2.70 and 3.35±1.95,respectively,in model group,which were higher than those in control group(0.21±0.09,1.36±0.77 and 0.52±0.19,all P values＜0.01).The Western blotting results demonstrated that the expression of C-Jun protein in model group(0.93±0.41)was higher than that in control group (0.32±0.25,P=0.001).Conclusion TGFβ1/Smad4 signal pathway might be involved in the development of hepatic fibrosis in NAFLD.Blocking TGFβ1/Smad4 signal pathway will be helpful in treatment of NAFLD.

OBJECTIVETo investigate the characteristic of integrons and the relationship between integrons and antimicrobial resistance in Shigella spp.

METHODSNinety Shigella strains (83 S. flexneri and 7 S. sonnei) were isolated from the stools of patients in China. Susceptibility to 8 antimicrobials was tested for all isolated strains. PCR, RFLP and sequencing analysis of integrons were applied to all of them.

RESULTSHigh prevalence of multi-drug resistance (95.6%) was identified. Of the isolates 79 (87.8%) carried integrase genes of class 1 integron (3.3%), class 2 integron (10.0%) or both (74.4%). No intI3 was detected in the tested isolates. The prevalence of intI2 was significantly higher in isolates with multi-drug resistance to at least 3 antibiotics than that in isolates with resistance to 2 and less antibiotics (P<0.05). Gene cassettes dfrA17-aadA5, dfrA12-orfF-aadA2 of class 1 integron and dfrA1-sat1-aadA1 of class 2 integron were identified.

CONCLUSIONThe class 2 integron may play a role in the emergence of multi-drug resistance in Shigella spp.

Base Sequence ; China ; DNA Primers ; Drug Resistance, Microbial ; Drug Resistance, Multiple ; Integrons ; Polymerase Chain Reaction ; Polymorphism, Restriction Fragment Length ; Shigella ; drug effects ; genetics

We report a case of a male patient who developed persistent fever and central nervous system symptoms after eating raw snails for 10 days. The patient was diagnosed with Angiostrongyliasis depended on the clinical presentation, epidemiological history, and etiological results. The patient recovered after receiving albendazole anthelmintic and dexamethasone anti-inflammatory therapy. This article incorporates literature review to sort out the diagnosis and treatment of this patient, in order to provide feasible reference for clinicians.

Objective:To analyze the lifestyle for brain health related factors and demographic characteristics through machine learning to achieve the assessing effect of mild cognitive impairement prevalence risk among rural elderly people in Guizhou.Methods:From July to August 2019, a multi-stage cluster random sampling method was used to select 1 235 rural elderly people aged 60 years and above in Guizhou Province as the subjects, and the investigation was performed with questionnaire and physical examination.The Mini-Mental State Examination (MMSE) was used to assess cognitive function, and the important features and optimal number of features based on 12 LIBRA factors and 4 demographic characteristics were selected.Logistic regression and random forest algorithm were used to establish a evaluation model for the risk of mild cognitive impairment in the elderly.The evaluation efficacy of the model was also assessed using a combination of precision, accuracy, sensitivity, specificity, F1 score and area under curve (AUC) of receiver operating characteristic curve, and the Delong method was used to check the difference of AUC values between the two models.Results:A total of 291 subjects were diagnosed with mild cognitive impairment, with a detection rate of 23.56% (291/1 235). The AUC values of logistic regression and random forest models evaluating the risk of mild cognitive impairment in the rural elderly were 0.758 and 0.820, respectively, and the differences were statistically significant(both P<0.05). The random forest model had better evaluations with an accuracy of 0.823, precision of 0.805, sensitivity of 0.874, specificity of 0.767 and F1 score of 0.838, all of which were better than those of the logistic regression model.And the random forest model was also more stable after 10-fold cross-validation. Conclusion:The lifestyle for brain health related factors combined with demographic characteristics can more accurately evaluate the risk of mild cognitive impairment among rural elderly people in Guizhou.The random forest model is better than the logistic regression model.

Objective:This study was aimed to explore the associations between the risk of dental fluorosis and the serum biomarkers of bone metabolism in children.Methods:A total of 502 children aged 7 - 12 years were selected by cluster sampling from 4 primary schools in Tongxu County, Kaifeng City, Henan Province from April to May 2017. Morning urine and fasting peripheral blood samples were collected from each participant. Urinary fluoride concentration was determined by fluoride ion selective electrode method. Serum calcium, phosphorus, alkaline phosphatase (ALP), bone-specific alkaline phosphatase (BALP), osteocalcin (OC), calcitonin (CT) and parathyroid hormone (PTH) levels were measured using an automatic biochemical analyzer. Dean method was used to evaluate the prevalence of dental fluorosis in children, and the participants were divided into dental fluorosis group ( n = 173) and control group ( n = 329) after being diagnosed by trained physicians for their dental fluorosis. The associations between the risk of dental fluorosis and the serum biomarkers of bone metabolism in children were analyzed by logistic regression. Results:The levels of serum phosphorus (mmol/L: 1.54 ± 0.19 vs 1.58 ± 0.21) and OC (ng/ml: 11.59 ± 5.22 vs 12.78 ± 5.88) in children in dental fluorosis group were significantly lower than those in children in control group ( P < 0.05). Logistic regression analysis showed that serum OC level affected the risk of dental fluorosis [odds ratio ( OR) = 0.96, 95% confidence interval ( CI): 0.92 - 0.99, P < 0.05]. The relative contribution of the biomarkers of bone metabolism to the risk of dental fluorosis in descending order were serum OC (36.34%), phosphorus (25.89%), BALP (13.16%), PTH (9.73%), calcium (9.44%), CT (3.72%) and ALP (1.72%). Conclusions:The prevalence of dental fluorosis in children is related to the changes of serum biomarkers of bone metabolism. Serum OC plays an important role in the occurrence of dental fluorosis.

Hepatitis B virus (HBV) is an important pathogen that causes different liver diseases such as viral hepatitis and liver cirrhosis. HBV pregenomic RNA (pgRNA) plays a crucial role in HBV life cycle, which is not only the translation template of core (C) and polymerase (P), but also the template of reverse transcription. The ratio of P protein to core protein is tightly regulated. Since P and core are both translated by pgRNA and the open reading frame (ORF) of P is located downstream of the ORF of core, how to initiate P protein translation is a key scientific question. Previous studies suggest that P can be translated through different mechanisms, such as leaky scanning and reinitiation. In this review, we summarized the proposed mechanisms relevant to the translation of polymerase from HBV pgRNA through literature review and derivation.

We report a case of a male patient who developed persistent fever and central nervous system symptoms after eating raw snails for 10 days. The patient was diagnosed with Angiostrongyliasis depended on the clinical presentation, epidemiological history, and etiological results. The patient recovered after receiving albendazole anthelmintic and dexamethasone anti-inflammatory therapy. This article incorporates literature review to sort out the diagnosis and treatment of this patient, in order to provide feasible reference for clinicians.