Quorum sensing systems of pathogens are central regulators for the expression of virulence factors. Increasing evidence implies that targeting the quorum sensing system of many pathogenic bacteria is a promising therapeutic approach to control infections. In this work,we isolated 47 strains of actinomycetes from the mud sample of Jiaozhou Bay. Quorum sensing inhibitory activity was monitored by Chromobacterium violaceum CV026. As a result,the culture broth extract of actinomycetes WA-7 was found to have significant quorum sensing inhibitory activity. This strain was assigned to the genus Streptomyces based on its 16S rDNA sequence. Further investigation revealed that the extract could inhibit the quorum sensing-controlled violacein and proteases production of C. violaceum in a concentration-dependent manner.

In recent years, antibiotic resistance of bacteria has become a global health crisis. Especially, the new class of "superbug" was found in South Asia, which is resistant to almost known antibiotics and causes worldwide alarm. Through the underlying mechanisms of bacterial pathogenecity, the expression of many pathogen virulence factors is regulated by the process of quorum sensing. Screening efficient quorum sensing inhibitors is an especially compelling approach to the future treatment of bacterial infections and antibiotic resistance. This article focuses on bacterial quorum sensing system, quorum sensing screening model for in vitro and evaluation of animal models in vivo, recent research of quorum sensing inhibitors and so on.
Animals ; Anti-Bacterial Agents ; pharmacology ; therapeutic use ; Bacterial Infections ; drug therapy ; Disease Models, Animal ; Drug Resistance, Bacterial ; Drugs, Chinese Herbal ; pharmacology ; Humans ; Pseudomonas aeruginosa ; drug effects ; pathogenicity ; physiology ; Quorum Sensing ; drug effects ; physiology ; Virulence ; drug effects ; Virulence Factors ; metabolism

The present article summarized development history and domestic and foreign research condition of intelli‐gent diagnostic technique , focused on its development and application in ECG diagnosis , narrated methods and di‐agnostic process of ECG intelligent diagnosis , and made an investigation and prospect on development of ECG intel‐ligent diagnostic technique .

Objective To explore the effects and related mechanisms of cilostazol on rat vascular smooth muscle cells (VSMCs)proliferation.Methods VSMCs were treated with DMEM (control) and various doses of cilostazol (1.0 × 10-7,2.5 × 10-7,5.0 × 10-7,7.5 × 10-7 and 1.0 × 10-6 mol/L) for 13 d (cell counting) or 72 h.Proliferation of VSMCs was investigated by cell-counting,MTT and flow cytometry analysis.Cell apoptosis was determined by TUNEL staining.mRNA and protein expressions of cell cycle regulatory proteins,such as Rb,p53 and p21 were detected by RT-PCR and Western blot,respectively.Results Cilostazol inhibited VSMCs proliferation and induced VSMCs arrest at G1 phase in a dose-dependent manner.High dose of cilostazol (7.5 × 10-7 and 1.0 × 10-6 mol/L) induced VSMCs apoptosis.p53 mRNA expression in 2.5 × 10-7 mol/L to 7.5 × 10-7 mol/L groups as well as 1.0 × 10-6 mol/L group (3.22 ±0.45 vs.1.75 ±0.32) and p53 protein expression in 7.5 × 10-7 mol/L group and 1.0 × 10-6 mol/L group (0.53 ± 0.11 vs.0.18 ± 0.06) were significantly upregulated after 72 h culture (all P＜0.05 vs.control).Low dose of cilostazol (1.0 × 10-7,2.5 × 10-7 and 5.0 × 10-7 mol/L)significantly upregulated p21 mRNA expression compared to control group (1.86 ± 0.19,2.20 ± 0.24 and 2.10 ± 0.18 vs.1.210 ± 0.18,all P ＜ 0.05).Similarly,Rb mRNA expression was significantly upregulated in 1.0 × 10-7,2.5 × 10-7 and 5.0 × 10 7 mol/L groups (0.89 ±0.07 vs.0.38 ±0.04)compared with control group (all P ＜ 0.05).However,high dose cilostazol (7.5 × 10-7 and 1.0 × 10-6mol/L) significantly downregulated p21 mRNA expression (0.81 ±0.09 vs.1.21 ±0.18,0.36 ±0.10 vs.1.2t ±0.18,all P ＜0.05 vs.control) and Rb mRNA expression (0.12 ±0.02 and 0.11 ±0.02 vs.0.38± ± 0.04,all P ＜ 0.05 vs.control).p21 and Rb protein expressions also upregulated at low concentrations of cilostazol and downregulated at high concentrations of cilostazol.Conclusion Cilostazol could inhibit the proliferation of rat VSMCs through modulating Rb-p53-p21 pathway and induce VSMCs apoptosis through upregulating p53.

OBJECTIVETo explore the prevalence of vision, mental, audibility, language, psychiatry, extremity, and influence factors in the 0 - 7 year olds.

METHODSA total number of 77,727 0 - 7 year old children living in Shenzhen city were tested with tree phase screening under the Chinese standard of evaluation in disabilities.

RESULTSThe prevalence of all disabilities was 5.59 per thousand (adjusted rate was 8.49 per thousand with a false negative of 3.1 per thousand ). The prevalence of mental disease was the highest (1.88 per thousand, with adjusted rate 3.43 per thousand ), the prevalence of language disability was 1.88 per thousand (including retarded language development, with adjusted rate 3.43 per thousand ). The prevalence rates of psychiatry, extremity and audibility disability were 1.59 per thousand, 1.56 per thousand, 1.11 per thousand respectively with of vision the lowest (0.37 per thousand ). The prevalence of all disabilities, audibility, language and mental was on the increase with age. The difference was statistically significant. Among all different age groups regarding psychiatric disease, the highest fell in the 2 - 4 year olds. The prevalence of extremity was not statistically different among age groups. The suspected agents of disease which occurred before or during pregnancy took up 45.7%.

CONCLUSIONThe prevalence of six kinds disabilities in Shenzhen was about 10 per thousand lower than that of the samples of the nation in 1989, but two times higher than that of similar studies in Japan. The prevalence rates of language and psychiatric disease were higher than that of the nation in 1989. The causation should be further studied.

Age Factors ; Child ; Child, Preschool ; China ; epidemiology ; Cross-Sectional Studies ; Disabled Children ; Female ; Humans ; Infant ; Infant, Newborn ; Language Disorders ; epidemiology ; Male ; Mental Disorders ; epidemiology ; Prevalence ; Vision Disorders ; epidemiology

OBJECTIVETo study the prevalence of severe acute respiratory syndrome coronavirus (SARS-CoV) like virus in animals at a live animal market of Guanzhou in 2004 before and after culling of wild animal action taken by the local authority, in order to predict the re-emerging of SARS from animal originals in this region.

METHODSAnimals at live animal market were sampled for rectal and throat swabs in triplicate. A single step realtime reverse transcription-polymerase chain reaction (RT-PCR) diagnostic kit was performed for screening SARS-CoV like virus, the manual nested RT- PCR and DNA sequencing were performed for confirmation. Only specimens which tested positive for both of the N and P genes by nested RT-PCR were scored as positive.

RESULTSIn 31 animals sampled in January 5 2004 before culling of wild animals at Guangdong Province, including 20 cats (Felis catus), 5 red fox (Vulpes vulpes) and 6 Lesser rice field rats (Rattus losea), 8 (25.8%) animals were tested positive for SARS-CoV like virus by RT-PCR methods, of which 4 cats, 3 red fox and one Lesser rice field rats were included. However, two weeks after culling of animals and disinfection of the market were implemented, in 119 animals sampled in January 20 2004, including 6 rabbits (Oryctolagus cuniculus), 13 cats, 46 red jungle fowl (Gallus gallus), 13 spotbill duck (Anas platyrhynchos), 10 greylag goose (Anser anser), 31 Chinese francolin (Franclinus pintadeanus), only rectal swab from one greylag goose was tested positive for SARS-CoV like virus. Furthermore, in 102 animals that including 14 greylag gooses, 3 cats, 5 rabbits, 9 spotbill duck (Anaspoecilorhyncha), 2 Chinese francolin (Franclinus pintadeanus), 8 common pheasant (Phasianus colchicus), 6 pigeons, 9 Chinese muntjac (Muntiacus reevesi), 19 wild boar (Sus scrofa), 16 Lesser rice field rats, 5 dogs, 1 mink (Mustela vison), 3 goats, 2 green peafowl (Pavo muticus) sampled in April, May, June, July, August and November, only rectal swab from one pig was tested positive. However, of 12 and 10 palm civets sampled in November and December including five of which had been at the live animals market for 2 days, none of them was tested positive.

CONCLUSIONThis findings revealed that animals being sampled in April, May, June, July, August and November of 2004, only one rectal swab from a pig was tested positive as SARS-CoV like virus, much lower than the results from the previous year, suggesting that the possibility of re-emerging of human infection from animal origins is low for the winter of 2004-2005.

Animals ; Animals, Wild ; virology ; China ; DNA, Viral ; analysis ; Felidae ; virology ; Reverse Transcriptase Polymerase Chain Reaction ; SARS Virus ; isolation & purification

Objective To investigate the prevalence and influencing factors of Enterobius vermicularis infections among children in Fanxian County, Henan Province in 2019, so as to provide insights into the management of enterobiasis. Methods Five kindergartens were selected in urban and rural areas of Fanxian County, Henan Province using the stratified sampling method in 2019, and a census of E. vermicularis infections was performed among all children in the kindergartens. E. vermicularis eggs were detected using adhesive and scotch cellophane-tape anal swab methods, and the basic characteristics of children and their families, health habits and the kindergartens’ information were investigated with questionnaires. Logistic regression analysis was used to investigate the risk factors and protective factors of pinworm infection in children. Results A total of 671 children were tested, and the mean prevalence of E. vermicularis infections was 15.50% (104/671). The prevalence of E. vermicularis infections was higher among children in rural kindergartens (28.13%, 72/256) than in urban kindergartens (7.71%, 32/415) (χ² = 50.380, P < 0.01), and greater in private kindergartens (32.26%, 60/186) than in public kindergartens (9.07%, 44/485) (χ² = 55.183, P < 0.01). There was no gender-specific prevalence of E. vermicularis infections among children (χ² = 1.442, P > 0.05), and the prevalence of E. vermicularis infections presented a tendency towards a rise with age (χ²_trend = 8.373, P < 0.05) and school grade (χ²_trend = 30.274, P < 0.05). Logistic regression analysis identified rural kindergartens and high grades as risk factors, and separate washing of children’s and adults’ cloths, frequent bathing and frequent dinnerware disinfection in kindergartens as protective factors for E. vermicularis infections among children. In addition, there was no significant difference in the detection of E. vermicularis infections among children by using adhesive (73.08%, 76/104) and scotch cellophane-tape anal swab methods (56.73%, 59/104) (χ² = 3.959, P > 0.05). Conclusions The prevalence of E. vermicularis infection is high among children in Fanxian Country, Henan Province. Health education and surveillance of enterobiasis are required to be intensified among children in rural kindergartens and senior grades and their parents and teachers.

Ventricular Function, Right ; Heart Ventricles/diagnostic imaging* ; Echocardiography

Objective: Several COVID-19 patients have overlapping comorbidities. The independent role of each component contributing to the risk of COVID-19 is unknown, and how some non-cardiometabolic comorbidities affect the risk of COVID-19 remains unclear. Methods: A retrospective follow-up design was adopted. A total of 1,160 laboratory-confirmed patients were enrolled from nine provinces in China. Data on comorbidities were obtained from the patients' medical records. Multivariable logistic regression models were used to estimate the odds ratio ( Results: Overall, 158 (13.6%) patients were diagnosed with severe illness and 32 (2.7%) had unfavorable outcomes. Hypertension (2.87, 1.30-6.32), type 2 diabetes (T2DM) (3.57, 2.32-5.49), cardiovascular disease (CVD) (3.78, 1.81-7.89), fatty liver disease (7.53, 1.96-28.96), hyperlipidemia (2.15, 1.26-3.67), other lung diseases (6.00, 3.01-11.96), and electrolyte imbalance (10.40, 3.00-26.10) were independently linked to increased odds of being severely ill. T2DM (6.07, 2.89-12.75), CVD (8.47, 6.03-11.89), and electrolyte imbalance (19.44, 11.47-32.96) were also strong predictors of unfavorable outcomes. Women with comorbidities were more likely to have severe disease on admission (5.46, 3.25-9.19), while men with comorbidities were more likely to have unfavorable treatment outcomes (6.58, 1.46-29.64) within two weeks. Conclusion Besides hypertension, diabetes, and CVD, fatty liver disease, hyperlipidemia, other lung diseases, and electrolyte imbalance were independent risk factors for COVID-19 severity and poor treatment outcome. Women with comorbidities were more likely to have severe disease, while men with comorbidities were more likely to have unfavorable treatment outcomes.
Adult ; Aged ; COVID-19/virology* ; China/epidemiology* ; Comorbidity ; Female ; Humans ; Male ; Middle Aged ; Retrospective Studies ; Severity of Illness Index ; Treatment Outcome