Porphyromonas gingivalis is an important pathogenic bacterium causing a variety of oral and systemic diseases. The LuxS/AI-2 quorum sensing system plays a key role in regulating numerous physiological processes such as biofilm formation, virulence factors and drug resistance in Porphyromonas gingivalis. Quorum sensing inhibitors are a new potential antibiotic substitute, a new method to control bacterial infection under the inhibition of biofilm formation, bacterial virulence and no induction of antibiotic resistance. This review is a summary of the research progress of the LuxS/AI-2 quorum sensing system in regulating biofilm formation, virulence, resistance and quorum sensing inhibitors in Porphyromonas gingivalis, and provides a theoretical basis for further research on the inhibitory targets of the LuxS/AI-2 quorum sensing system in Porphyromonas gingivalis.

Objective:To evaluate the role of the Toll-like receptor 4 (TLR4)-myeloid differentiation factor 88 (MyD88)-tumor necrosis factor receptor-associated factor 6 (TRAF6) signaling pathway in the reduction of cerebral ischemia-reperfusion injury (CIRI) by trilobatin pretreatment in rats.Methods:Eighty clean-grade healthy male Sprague-Dawley rats, aged 8 weeks, weighing 250-300 g, were divided into 4 groups ( n=20 each) using a random number table method: sham operation group (group S), group CIRI, trilobatin+ CIRI group (group TC) and trilobatin+ CIRI+ AAV-TLR4 group (group TCA). The model of CIRI was established by middle cerebral artery occlusion in anesthetized animals in CIRI, TC and TCA groups. In group TCA, the adeno associated virus was injected into the cortical region to up-regulate the expression of TLR4 at 21 days before developing the model. Trilobatin 15 mg/kg was administered by gavage twice daily for 3 days prior to ischemia in TC and TCA groups. The cognitive function was assessed using the modified Longa score at 24 h of reperfusion. Then the rats were sacrificed and the whole brain tissues were isolated for determination of the cerebral infarct size (by TTC staining), expression of TLR4, MyD88 and TRAF6 (by Western blot), and contents of interleukin-1 beta (IL-1β), IL-6 and tumor necrosis factor-alpha (TNF-α) (by enzyme-linked immunosorbent assay) and for microscopic examination of the neuronal ultrastructure in ischemic cerebral cortex tissues (with a transmission electron microscope). Results:Compared with group S, the Longa score and percentage of cerebral infarct size were significantly increased, the expression of TLR4, MyD88 and TRAF6 in cerebral cortex tissues of ischemic regions was up-regulated, the contents of IL-1β, IL-6 and TNF-α were increased ( P<0.05), and the pathological damage to cortical neurons was aggravated in CIRI group. Compared with group CIRI, the Longa score and percentage of cerebral infarct size were significantly decreased, the expression of TLR4, MyD88 and TRAF6 was down-regulated, the contents of IL-1β, IL-6 and TNF-α were decreased in cerebral cortex tissues of ischemic regions ( P<0.05), and the pathological damage to cortical neurons was significantly attenuated in group TC. Compared with group TC, the Longa score and percentage of cerebral infarct size were significantly increased, the expression of TLR4, MyD88 and TRAF6 was up-regulated, the contents of IL-1β, IL-6 and TNF-α were increased in cerebral cortex tissues of ischemic regions ( P<0.05), and the pathological damage to cortical neurons was aggravated in group TCA. Conclusions:The TLR4-MyD88-TRAF6 signaling pathway is involved in the reduction of cerebral I/R injury by trilobatin pretreatment in rats.

The drugs used to improve brain metabolism mainly include ergotamine derivatives,GABA derivatives,vitamin B6 derivatives,neuropeptides,morpholines,hormones and other.However,these drugs may have adverse reactions during clinical application.This article focuses on the adverse effects of commonly used drugs for brain metabolism,and reviews the studies on the new state of pharmaceutical substances,such as drug combination,chiral resolution of isomers,crystal form of dominant drugs,co-crystal drugs and nanodrugs,with the aim of reducing adverse reactions.By summarizing the research on modifying the solid state of drugs to mitigate adverse reactions,this article provides new research insights for obtaining new drug with less adverse reaction and greater clinical value.

Objective:To evaluate the role of the Toll-like receptor 4 (TLR4)-myeloid differentiation factor 88 (MyD88)-tumor necrosis factor receptor-associated factor 6 (TRAF6) signaling pathway in the reduction of cerebral ischemia-reperfusion injury (CIRI) by trilobatin pretreatment in rats.Methods:Eighty clean-grade healthy male Sprague-Dawley rats, aged 8 weeks, weighing 250-300 g, were divided into 4 groups ( n=20 each) using a random number table method: sham operation group (group S), group CIRI, trilobatin+ CIRI group (group TC) and trilobatin+ CIRI+ AAV-TLR4 group (group TCA). The model of CIRI was established by middle cerebral artery occlusion in anesthetized animals in CIRI, TC and TCA groups. In group TCA, the adeno associated virus was injected into the cortical region to up-regulate the expression of TLR4 at 21 days before developing the model. Trilobatin 15 mg/kg was administered by gavage twice daily for 3 days prior to ischemia in TC and TCA groups. The cognitive function was assessed using the modified Longa score at 24 h of reperfusion. Then the rats were sacrificed and the whole brain tissues were isolated for determination of the cerebral infarct size (by TTC staining), expression of TLR4, MyD88 and TRAF6 (by Western blot), and contents of interleukin-1 beta (IL-1β), IL-6 and tumor necrosis factor-alpha (TNF-α) (by enzyme-linked immunosorbent assay) and for microscopic examination of the neuronal ultrastructure in ischemic cerebral cortex tissues (with a transmission electron microscope). Results:Compared with group S, the Longa score and percentage of cerebral infarct size were significantly increased, the expression of TLR4, MyD88 and TRAF6 in cerebral cortex tissues of ischemic regions was up-regulated, the contents of IL-1β, IL-6 and TNF-α were increased ( P<0.05), and the pathological damage to cortical neurons was aggravated in CIRI group. Compared with group CIRI, the Longa score and percentage of cerebral infarct size were significantly decreased, the expression of TLR4, MyD88 and TRAF6 was down-regulated, the contents of IL-1β, IL-6 and TNF-α were decreased in cerebral cortex tissues of ischemic regions ( P<0.05), and the pathological damage to cortical neurons was significantly attenuated in group TC. Compared with group TC, the Longa score and percentage of cerebral infarct size were significantly increased, the expression of TLR4, MyD88 and TRAF6 was up-regulated, the contents of IL-1β, IL-6 and TNF-α were increased in cerebral cortex tissues of ischemic regions ( P<0.05), and the pathological damage to cortical neurons was aggravated in group TCA. Conclusions:The TLR4-MyD88-TRAF6 signaling pathway is involved in the reduction of cerebral I/R injury by trilobatin pretreatment in rats.

The drugs used to improve brain metabolism mainly include ergotamine derivatives,GABA derivatives,vitamin B6 derivatives,neuropeptides,morpholines,hormones and other.However,these drugs may have adverse reactions during clinical application.This article focuses on the adverse effects of commonly used drugs for brain metabolism,and reviews the studies on the new state of pharmaceutical substances,such as drug combination,chiral resolution of isomers,crystal form of dominant drugs,co-crystal drugs and nanodrugs,with the aim of reducing adverse reactions.By summarizing the research on modifying the solid state of drugs to mitigate adverse reactions,this article provides new research insights for obtaining new drug with less adverse reaction and greater clinical value.

Porphyromonas gingivalis is an important pathogenic bacterium causing a variety of oral and systemic diseases. The LuxS/AI-2 quorum sensing system plays a key role in regulating numerous physiological processes such as biofilm formation, virulence factors and drug resistance in Porphyromonas gingivalis. Quorum sensing inhibitors are a new potential antibiotic substitute, a new method to control bacterial infection under the inhibition of biofilm formation, bacterial virulence and no induction of antibiotic resistance. This review is a summary of the research progress of the LuxS/AI-2 quorum sensing system in regulating biofilm formation, virulence, resistance and quorum sensing inhibitors in Porphyromonas gingivalis, and provides a theoretical basis for further research on the inhibitory targets of the LuxS/AI-2 quorum sensing system in Porphyromonas gingivalis.

Objective:To investigate the clinical data of asymptomatic patients with 2019 novel Coronavirus (2019-nCoV) infection in Shijiazhuang and provide scientific evidence for prevention and treatment of Coronavirus Disease 2019(COVID-19).Methods:Retrospective study was conducted to analyze the clinical features and laboratory data of 9 asymptomatic 2019-nCoV infected patients, admitted to the Fifth Hospital of Shijiazhuang from January 21, 2020 to February 21, 2020.Results:Asymptomatic infection was found in all age groups, including 5 males and 4 females. On the first day of admission, the detection result of leukocytes, lymphocytes and neutrophils in asymptomatic patients were at normal levels. On the third day after admission, the results increased and continued to stabilize on the twelfth day. The levels of alanine aminotransferase and lactate dehydrogenase were at normal levels during hospitalization, without transient increase or decrease. The level of C-reactive protein reached the highest level on the third day after admission, but it was always in the normal range. D-dimer level was relatively stable during hospitalization. The absolute value of T cell subsets showed that the levels of CD 3+ , CD 4+ , CD 8+ T cells in asymptomatic infection patients were higher than those determined before admission. The average duration of pharyngeal nucleic acid positive detection in asymptomatic patients was 11.88 days. The average cycle threshold of ORF1ab gene and N gene was 36.94 and 35.43 respectively. Conclusions:The inflammatory reaction in patients with asymptomatic 2019-nCoV infection was mild, and the immune function was relatively good.

Objective:To understand the employment situation of graduates of public health-related majors and explore the associated factors of turnover intention among public health practitioners in China.Methods:In April 2020, the convenient sampling method was used to recruit public health related graduates from 98 universities with public health-related majors from 31 provinces in China (excluding Hong Kong, Macao and Taiwan) and from Chinese Center for Disease Control and Prevention (only including working or unemployed status, no requirement for graduation years). A total of 1 322 questionnaires were collected, of which 1 165 (88.1%) were valid. Through the network questionnaire survey, the information of public health graduates′ work situation, job satisfaction and turnover intention were collected. Multivariate logistic regression model was used to analyze the associated factors of turnover intention, and structural equation model was constructed to explore the correlation between turnover intention and job satisfaction.Results:The age of 1 165 graduates was (28.1 ±4.8) years. Among them, 719 (61.7%) were female and 856 (73.5%) graduates were engaged in public health-related work after graduation. The results of multivariate logistic regression analysis showed that compared with those over 30 years old, graduates under 30 years old had higher turnover intention ( OR=2.531, 95% CI: 1.549-4.155). Compared with those with junior or no title, graduates with senior title had higher turnover intention ( OR=2.310, 95% CI: 1.047-5.162). The results of structural equation model analysis showed that the four factors of job satisfaction, ‘salary and welfare’, ‘promotion development’, ‘work itself’, and ‘internal and external environment’, were negatively correlated with turnover intention. The internal and external environment had the greatest impact on turnover intention (total effect =-0.539). Conclusion:Most graduates of public health-related majors are engaged in public health-related work in China. Age, professional title and job satisfaction are the associated factors of turnover intention.

Objective:To understand the employment situation of graduates of public health-related majors and explore the associated factors of turnover intention among public health practitioners in China.Methods:In April 2020, the convenient sampling method was used to recruit public health related graduates from 98 universities with public health-related majors from 31 provinces in China (excluding Hong Kong, Macao and Taiwan) and from Chinese Center for Disease Control and Prevention (only including working or unemployed status, no requirement for graduation years). A total of 1 322 questionnaires were collected, of which 1 165 (88.1%) were valid. Through the network questionnaire survey, the information of public health graduates′ work situation, job satisfaction and turnover intention were collected. Multivariate logistic regression model was used to analyze the associated factors of turnover intention, and structural equation model was constructed to explore the correlation between turnover intention and job satisfaction.Results:The age of 1 165 graduates was (28.1 ±4.8) years. Among them, 719 (61.7%) were female and 856 (73.5%) graduates were engaged in public health-related work after graduation. The results of multivariate logistic regression analysis showed that compared with those over 30 years old, graduates under 30 years old had higher turnover intention ( OR=2.531, 95% CI: 1.549-4.155). Compared with those with junior or no title, graduates with senior title had higher turnover intention ( OR=2.310, 95% CI: 1.047-5.162). The results of structural equation model analysis showed that the four factors of job satisfaction, ‘salary and welfare’, ‘promotion development’, ‘work itself’, and ‘internal and external environment’, were negatively correlated with turnover intention. The internal and external environment had the greatest impact on turnover intention (total effect =-0.539). Conclusion:Most graduates of public health-related majors are engaged in public health-related work in China. Age, professional title and job satisfaction are the associated factors of turnover intention.

Objective:To investigate public health-related professions' recruit requirements and understand the training scheme for preventive medicine-majored undergraduates in colleges and universities in China.Methods:An online questionnaire was adopted to collect data on the recruit requirements of public health-related professions. Information on the core courses, internship, and practical training for preventive medicine-majored undergraduates was collected through universities' official websites.Results:The employers had a high requirement for education and specific majors. Also, administration professions attached importance to comprehensive quality, while professional positions to professional skills. 47.2% (67/142) employers made Talent Introduction Programs for the next three years. 20.0% (3/15) universities offered all the core courses required by national standards. For internship and practical training, both clinical practice and professional practice's median durations were 16 and 11 weeks, respectively.Conclusion:Employers showed significant demand for public health graduates and having a high requirement for personal ability and comprehensive quality. The universities should improve the setting of core courses and strengthen students' practical ability and overall quality.