Physicochemical Processes of Biofilm Formation on The Surface of Structures in Water / 生物化学与生物物理进展

Microorganisms can form biofilms, complex, heterogeneous, multicellular communities that adhere to surfaces. Biofilm formation on the surface of structures in water will accelerate structures’ corrosion, seriously affect their service efficiency and life, and significantly impact the growth of animals, plants, and human life. Hence, clarifying the mechanism of biofilm formation contributes to developing new strategies to control biofilm formation on surface and then reduce infections, biofouling, and contaminations. Biofilm-targeting strategies include the regulation of established biofilms or the modulation of single-cell attachment. In most studies, physicochemical mechanism is frequently applied to explain the initial bacterial adhesion phenomena but rarely to explain other stages of biofilm formation. This review presents a five-step comprehensive description of the physicochemical process from film formation to biofilm maturation: (1) period of film formation; (2) period of bacterial adhesion; (3) period of extracellular-polymeric-substances (EPSs) membrane formation; (4) period of regulating biofilm by quorum sensing (QS); (5) period of biofilm maturation. We first clarify how the film formed by compound molecules affects the surface’s physicochemical properties and initial adhesion, summarizing many factors that affect bacterial adhesion. We then review the types of EPSs and signal molecules secreted by bacteria after irreversible adhesion, as well as their role and QS mechanism in biofilm maturation. Finally, we discuss how bacteria or microcolonies separate from the mature biofilm by physicochemical action and summarize the morphology and adhesion characterization methods after the biofilm matures. This review redefines the role of physicochemical in the whole process of biofilm formation and provides a theoretical basis for the prevention, removal, and utilization of biofilm and other related research fields.

Gender Differences in the Prevalence of Overweight and Obesity, Associated Behaviors, and Weight-related Perceptions in a National Survey of Primary School Children in China / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>To in vestigate potential gender differences in the odds of overweight/obese, weight-related perceptions, and behaviors among Chinese school children.</p><p><b>METHODS</b>Height, weight, and a survey of weight-related perceptions and behaviors were measured in a nationally representative survey of 12,811 children in primary schools in China. Logistic regression analyses were used to assess gender differences, adjusting for confounders.</p><p><b>RESULTS</b>Boys had higher odds of being overweight/obese compared to girls within both urban [adjusted odds ratio (OR) 2.30, 95% CI 2.00 to 2.65] and rural areas (OR = 1.85, 95% CI 1.55 to 2.20). Girls reported healthier diets (e.g., daily vegetables OR = 0.79, 95% CI 0.73 to 0.85) whereas boys consumed fried food (OR = 1.21, 95% CI 1.06 to 1.38) and sugar-sweetened drinks more often (OR = 1.49, 95% CI 1.34 to 1.65). Gender differences included higher odds of boys perceiving themselves as overweight if they had more highly educated mothers (OR = 1.35, 95% CI 1.09 to 1.68), less educated fathers (OR = 0.79, 95% CI 0.63 to 0.99), and if they frequently consumed carbonated drinks (OR = 1.48, 95% CI 1.07 to 2.05).</p><p><b>CONCLUSION</b>Childhood obesity prevention in China should be gender-focused, particularly for boys who reported an unhealthier diet but were less likely to see they were fat, even though more boys were overweight or obese than girls.</p>

Prevalence and Correlates of Elevated Blood Pressure in Chinese Children Aged 6-13 Years: a Nationwide School-Based Survey / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>To estimate the prevalence of elevated blood pressure (EBP) in Chinese children and identify individual and family factors associated with EBP.</p><p><b>METHODS</b>A nationwide cross-sectional study was conducted in 2010 using stratified cluster sampling. Participants' blood pressure was measured, and their parents completed a questionnaire on personal and family characteristics. Prevalence and correlates of EBP were assessed.</p><p><b>RESULTS</b>Among a total of 24,333 participants, 20.2% of boys and 16.3% of girls had EBP. The prevalence of EBP increased with the ascending trend of waist circumference, Waist-to-height ratio, and body mass index. The adjusted prevalence ratios (aPRs) for obese boys and girls were 2.50 and 2.97, respectively. Fewer urban boys (16.2%) had EBP than rural boys (21.7%). Boys with a family history of hypertension were 12% more likely to have EBP. Children whose mothers received a college education tended to have lower likelihood of EBP; with an aPR was 0.85 among boys and 0.78 among girls.</p><p><b>CONCLUSION</b>EBP is common among obese students and those who have a family history of hypertension. A negative association between mothers' education levels and EBP risk in children was found.</p>

The relationship between socioeconomic status and overweight and obesity among elementary school children in China / 中华预防医学杂志

<p><b>OBJECTIVE</b>To analyze the relationship between socioeconomic status (SES) and overweight and obesity among elementary school children.</p><p><b>METHODS</b>This cross-sectional study was conducted from September to November, 2010. A stratified random cluster sampling was used from sampling frame of eight provinces by the geographical and economic development distributions in mainland China. A total of 19 934 students aged 7-12 years old participated in this study. All subjects were evaluated the status of overweight and obesity. Green's scoring SES was used to evaluate the SES of the participants. Multivariate logistic regression analysis was performed to examine the relationship between SES and overweight and obesity among children.</p><p><b>RESULTS</b>According to the scores of Green's SES, the participants' SES were divided into three levels, the prevalence of overweight were 7.4% (538/7295), 9.3% (560/6013) and 12.6% (832/6626), and the prevalence of obesity were 4.4% (321/7295) , 6.4% (387/6013) and 10.2% (677/6626) from low to high SES level, respectively (χ(2) value were 133.82, 180.27, respectively, P < 0.01). After adjusted by age, urban and rural and economic regions, compared with the participants with low SES, the OR (95%CI) of having overweight and obesity among participants with high SES were 1.83(1.61-2.08) for boys and 1.67(1.42-2.00) for girls; the OR (95%CI) with middle SES were 1.30(1.15-1.48) for boys and 1.23(1.04-1.46) for girls.</p><p><b>CONCLUSION</b>The prevalence of overweight and obesity rises with the family's SES levels. There was a positive correlation between SES and overweight and obesity among school-aged children.</p>

Establishment of primary cultured neurons model of mouse embryo with HSV-1 infection / 中华实验和临床病毒学杂志

<p><b>BACKGROUND</b>To establish a neurons model for herpes simplex virus type 1 (HSV-1) infection using cultures of mouse embryo.</p><p><b>METHODS</b>The cortical neuron of 14-16 day old mouse embryo were cultured and infected with HSV-1. Microscopic examination, immunofluorescent test, MTT colorimetric analysis and flowcytometric assay were used to detect the immunofluorescent reaction of normal and infected neurons and astrocytes, respectively. The percentage of the two kinds of cells were measured.</p><p><b>RESULTS</b>The mouse neurons could proliferate well in vitro. The neurons amount met the requirement of cytological experiment after treatment with Ara-C in the tissue culture. HSV-1 could infect the neurons directly, the activity of the infected neurons was obviously reduced.</p><p><b>CONCLUSION</b>HSV-1 could successfully infect the primary cultured neurons. The model may provide a useful approach for studying the pathogenesis of herpes simplex virus encephalitis.</p>