中国沿海浒苔属rbcL和ITS序列比较及系统进化分析

为阐明中国沿海浒苔的亲缘关系及地理分布特点,采集青岛栈桥、盐城弶港、宁波象山、温州平阳四地浒苔样本,克隆测序得到ITS1、5.8SrDNA和ITS23种不同长度序列片段。四个地区的rbcL目的片段,长度均为1201bp。分析核苷酸差异和遗传距离,采用邻接法建立系统发生树。结果显示,ITS序列进化速率较快,rbcL序列相当保守。ITS区较短,GC含量均在65%以上,5.8SrDNA的CG含量在50%左右,ITS1区的序列差异大于ITS2区。四个地区的浒苔存在一定的地理差异,盐城和青岛的样本间的亲缘关系较近;宁波和温州的样本间的亲缘关系较近。石莼属(Ulva)和浒苔属(Enteromorpha)的物种没有聚成各自独立的分枝,而是相互混合在一起,应是两个亲缘关系相近的属。引起青岛绿潮的海藻很可能是来自盐城海域的Enteromorpha linza或Enteromorpha prolifera。     

噬菌体治疗细菌性感染及其限制因素

近年来,细菌耐药性已成为抗感染领域面临的严峻问题,临床对一些细菌性感染疾病束手无策。噬菌体疗法是一种通过噬菌体裂解细菌来治疗病原菌感染的治疗手段。噬菌体在抗菌领域表现出显著的优越性,成为目前治疗细菌性感染的研究热点。本文对近年来噬菌体治疗动物和人类病原菌感染、限制其临床应用的因素及解决措施进行综述。     

Combined analysis of the association between p73 G4C14-to-A4T14 polymorphisms and cancer risk

P73 is a structural and functional homologue of p53, and plays an important role in regulating cell cycle and apoptosis. A potentially functional polymorphism (designated as p73 G4C14-to-A4T14) has been identified in a region in exon 2 of the p73 gene, which may theoretically form a stem-loop structure and thereby affect p73 expression. Several investigations have reported the correlation between p73 G4C14-to-A4T14 polymorphism and cancer risk. However, the results are inconclusive. To further assess the association between p73 polymorphism and cancer risk, we performed meta-analysis of the data sets obtained from 26 individual studies involving 8,148 cancer patients and 8,150 controls. The association between p73 G4C14-to-A4T14 polymorphism and cancer risk was determined by crude odd ratios (OR) with 95% CI (confidential interval). AT-allele carriers were found to have a significantly increased risk of cervical cancer (AT/GC vs. GC/GC, OR = 1.63, 95% CI = 1.14–2.33; AT/AT + AT/GC vs. GC/GC, OR = 1.49, 95% CI = 1.05–2.10), colorectal cancer (AT/AT vs. AT/GC + GC/GC, OR = 1.98, 95% CI = 1.25–3.12), head and neck cancer (AT/AT + AT/GC vs. GC/GC, OR = 1.44, 95% CI = 1.06–1.96) and other cancers (AT/AT vs. GC/GC, OR = 1.78, 95% CI = 1.24–2.57; AT/AT vs. AT/GC + GC/GC, OR = 1.80, 95% CI = 1.26–2.56). In the stratified analysis of ethnicity, a significantly elevated cancer risk was found in Caucasians (AT/AT + AT/GC vs. GC/GC, OR = 1.18, 95% CI = 1.08–1.30; allele AT vs. allele GC, OR = 1.15, 95% CI = 1.06–1.24). No significant association of p73 polymorphism with the cancer risk of smoking was detected by stratified analysis by smoking status. Together, our data suggest that the p73 G4C14-to-A4T14 may be a risk factor of cancer especially in Caucasians.     

Body mass and behavior in Swiss mice subjected to continuous or discontinuous food restriction and refeeding

Food restriction (FR) is hypothesized to decrease body fat content of an animal and thus prevent obesity. However, the response of energy budget to a continuous (CFR) or discontinuous FR (DFR) remains inconsistent. In the present study, effects of CFR or DFR and refeeding on energy budget and behavior were examined in male Swiss mice. CFR significantly decreased the energy expenditure associated with basal metabolic rate (BMR) and activity behavior, but not sufficiently to compensate for energy deficit and thus resulted in lower body mass and fat content. DFR mice had a significantly higher food intake on ad libitum days and showed increases in BMR and activity after 4 weeks’ DFR, which might resulted in lower body mass and less body fat than controls. After being refed ad libitum, both CFR and DFR mice had similar body mass, BMR, and behavioral patterns to controls but had 95% and 75% higher fat content. This suggested that not only CFR but also DFR would be a significant factor in the process of obesity for animals that were refed ad libitum. It also indicated that food restriction interrupted many times by periods of ad libitum feeding had the same long-term effects like continuous underfeeding.     

Toxoplasma gondii α-amylase deletion mutant is a promising vaccine against acute and chronic toxoplasmosis

Individuals with inhibited immunity may develop lethal toxoplasmosis; thus, a safe and effective vaccine is urged to be developed. Toxoplasma gondii (T. gondii) α-amylase (α-AMY) is one of the enzymes responsible for starch digestion. In the present study, we first generated a ME49Δα-amy mutant and discovered that loss of α-AMY robustly grew in vitro but contributed to significant virulence attenuation in vivo. Therefore, we established a mouse model to explore the protective immunity of Δα-amy mutant against acute and chronic toxoplasmosis. The results indicated that the survival rates of short-term or long-term immunized mice re-infected with the tachyzoites of multiple T. gondii strains were nearly 100%. ME49Δα-amy not only could provide protective immunity against tachyzoites infection but also could resist the infection of tissue cysts. Furthermore, we detected that ME49Δα-amy vaccination could effectively eliminate the proliferation of parasites in mice and prevent the formation of cysts. The significant increases of Th1-type cytokines, Th2-type cytokines and specific total IgG and IgG subclasses (IgG2a and IgG1) confirmed efficiency of a combination of cellular and humoral immunity against infection. In conclusion, ME49Δα-amy attenuated strain can produce strong immune responses to provide efficient protection against toxoplasmosis, which signifies that ME49Δα-amy mutant may be a potential vaccine candidate.     

Psychosocial perception of adults with onychomycosis: a blinded,controlled comparison of 1,017 adult Hong Kong residents with or without onychomycosis

Background

A survey was conducted amongst 1,017 Hong Kong residents ages 18 and over to determine their knowledge of fungal nail infections (onychomycosis) and the psychosocial impact of the disease on the relationships, social lives and careers of sufferers.

Methods

The Fungal Nail Perception Survey was conducted by email and online between May 29th and June 10th, 2013. Participants were shown three photographs of people with and without onychomycosis of the toenails. Respondents were asked ten questions (repeated for each picture) to ascertain their perceptions of the people in the pictures. Questions were related to perceptions around the ability of sufferers and non-sufferers to form relationships with others, social activities of sufferers and non-sufferers, perceptions of the effect of the disease on the potential for career success, and awareness of fungal nail disease and health. The sub-population who themselves suffered from onychomycosis were asked about self-perception as well as their perception of others with onychomycosis.

Results

Compared with non-sufferers, survey respondents perceived those with onychomycosis as less likely to be able to form good relationships. They also indicated that they would be more likely to exclude sufferers than non-sufferers from social activities and that they would be more likely to feel uncomfortable when sitting or standing beside an infected person than beside an uninfected person. Respondents perceived people with onychomycosis to be less able to perform well in their chosen career than with someone without onychomycosis. Interestingly, those respondents who themselves were infected felt socially excluded, upset and embarrassed by their infection.

Conclusions

Onychomycosis may lead to stigmatization and social exclusion. Misconceptions of onychomycosis are high and education about the disease needs to be improved. Early recognition and treatment of the disease is essential to avoid complications and improve treatment outcomes, which would lead to reduced psychosocial impact on those with fungal nail infections.

     

Comparison of bioelectrical impedance and BMI in predicting obesity-related medical conditions

Objective : To determine the relative validity of specific bioelectrical impedance analysis (BIA) prediction equations and BMI as predictors of physiologically relevant general adiposity. Research Methods and Procedures : Subjects were >12, 000 men and women from the Third National Health and Nutrition Examination Survey population. We examined the correlations between BMI and percentage body fat based on 51 different predictive equations, blood pressure, and blood levels of glucose, high‐density lipoprotein cholesterol, and triglycerides, which are known to reflect adiposity, while controlling for other determinants of these physiological measures. Results : BMI consistently had one of the highest correlations across biological markers, and no BIA‐based measure was superior. Percent body fat estimated from BIA was minimally predictive of the physiological markers independent of BMI. Discussion : These results suggest that BIA is not superior to BMI as a predictor of overall adiposity in a general population.     

FIT2 organizes lipid droplet biogenesis with ER tubule-forming proteins and septins

Lipid droplets (LDs) are critical for lipid storage and energy metabolism. LDs form in the endoplasmic reticulum (ER). However, the molecular basis for LD biogenesis remains elusive. Here, we show that fat storage–inducing transmembrane protein 2 (FIT2) interacts with ER tubule-forming proteins Rtn4 and REEP5. The association is mainly transmembrane domain based and stimulated by oleic acid. Depletion of ER tubule-forming proteins decreases the number and size of LDs in cells and Caenorhabditis elegans, mimicking loss of FIT2. Through cytosolic loops, FIT2 binds to cytoskeletal protein septin 7, an interaction that is also required for normal LD biogenesis. Depletion of ER tubule-forming proteins or septins delays nascent LD formation. In addition, FIT2-interacting proteins are up-regulated during adipocyte differentiation, and ER tubule-forming proteins, septin 7, and FIT2 are transiently enriched at LD formation sites. Thus, FIT2-mediated nascent LD biogenesis is facilitated by ER tubule-forming proteins and septins.