Bio-aerosols in indoor environment: composition, health effects and analysis

Bio-aerosols are airborne particles that are living (bacteria, viruses and fungi) or originate from living organisms. Their presence in air is the result of dispersal from a site of colonization or growth. The health effects of bio-aerosols including infectious diseases, acute toxic effects, allergies and cancer coupled with the threat of bioterrorism and SARS have led to increased awareness on the importance of bio-aerosols. The evaluation of bio-aerosols includes use of variety of methods for sampling depending on the concentration of microorganisms expected. There have been problems in developing standard sampling methods, in proving a causal relationship and in establishing threshold limit values for exposures due to the complexity of composition of bio-aerosols, variations in human response to their exposure and difficulties in recovering microorganisms. Currently bio-aerosol monitoring in hospitals is carried out for epidemiological investigation of nosocomial infectious diseases, research into airborne microorganism spread and control, monitoring biohazardous procedures and use as a quality control measure. In India there is little awareness regarding the quality of indoor air, mould contamination in indoor environments, potential source for transmission of nosocomial infections in health care facilities. There is an urgent need to undertake study of indoor air, to generate baseline data and explore the link to nosocomial infections. This article is a review on composition, sources, modes of transmission, health effects and sampling methods used for evaluation of bio-aerosols, and also suggests control measures to reduce the loads of bio-aerosols.     

Symptoms suggestive of atopic rhinitis in children aged 6-9 years and the indoor environment

BACKGROUND: We aimed to investigate the influence of indoor factors on the prevalence of symptoms suggestive of atopic rhinitis in children aged 6-9 years in Upper Austria. METHODS: We analyzed the results from an extended ISAAC (International Study of Asthma and Allergies in Childhood) questionnaire, answered by the parents, about indoor environment and symptoms strongly suggesting atopic rhinitis. This was defined as having reported a running, obstructed, or itchy nose apart from having a cold in the last year. The overall response rate was 93.4%. After excluding 6,016 children (17.1%) with changed indoor environment (due to allergies in the family), we analyzed the remaining subsample of 18,606 questionnaires. RESULTS: The following factors were associated with an increased risk: mother's smoking during pregnancy and/or during time of breast-feeding (OR 1.28; CI 1.07-1.52), synthetic bedding (OR 1.21; CI 1.09-1.36), dampness/mold at home (OR 1.51; CI 1.31-1.74), central heating with gas (OR 1.75; CI 1.06-2.87), and space heating (OR 1.66; CI 1.01-2.98). Cooking with wood (OR 0.62; CI 0.46-0.84) was negatively associated with symptoms. CONCLUSIONS: The indoor environment plays a role in the symptoms of atopic rhinitis in children. However, the population-attributable risks were not particularly high; they were between -2.7% and 9% for the various exposures considered in this study.     

Early environmental factors and rheumatoid arthritis

The precise cause of autoimmune diseases such as rheumatoid arthritis (RA) remains uncertain. In recent years there has been extensive investment in pursuing genes important in RA. However, estimates suggest that the risk of developing RA is at most 50% determined by genes. There has been limited success defining the environmental factors important in developing RA. We hypothesize that this lack of success may be due to a concentration on the time around disease onset. There is evidence of production of the autoantibodies rheumatoid factor (RF) and anti-cyclic citrullinated peptides (anti-CCP) and increased levels of C-reactive protein (CRP) years before RA becomes clinically apparent. In addition, early life events including intrauterine growth retardation (IUGR) may have long lasting effects on immune function. We review the evidence that the early environment through effects on growth and infectious exposure may influence the likelihood of developing autoimmune diseases such as RA.     

多囊卵巢综合征与生殖道及肠道微生物组的相互作用

多囊卵巢综合征(Polycystic Ovary Syndrome,PCOS)是育龄女性最常见的内分泌代谢疾病之一,以高雄激素血症、多囊卵巢、稀发排卵或无排卵为主要临床特征。PCOS发病率高、表型复杂,病因及病理生理学机制尚不明确。近年来,有不少研究聚焦于人体微生物组在PCOS病理生理学机制中的作用。因此,本综述以多囊卵巢综合征与生殖道、肠道微生物组的相互作用为主题,总结探讨了PCOS患者的微生物组特征、PCOS如何影响人体微生物组以及人体微生物组在PCOS发生发展中的作用。     

VDR基因多态性、环境因素与重庆地区肺结核病的联系及交互作用研究

目的探讨维生素D受体(VDR)基因多态性、环境因素与结核病发病的相关性,以及因素间的交互作用。方法采用病例对照研究方法,选择198例确诊肺结核病例为病例组,按年龄、性别成组匹配195例健康人为对照组。采用高分辨率溶解曲线技术(HRM)检测VDR基因TaqⅠ、FokⅠ多态性位点的基因型,同时收集研究对象环境因素暴露情况,以单因素和多因素非条件Logistic回归分析的方法,分析VDR基因多态性、环境因素与结核病的联系及其交互作用。结果结核病患者接触史、吸烟、人均居住面积小于10 m2、居室通风不良、工作强度大以及VDR基因FokⅠ-ff基因型与结核病易感性相关(P<0.05),VDR基因FokⅠ-ff基因型、吸烟及结核病患者接触史在结核病发生中存在明显的交互作用(P<0.05)。结论 VDR基因多态性、环境因素与结核病的发病有关,且存在一定的交互作用。     

An overview of environmental risk factors in systemic sclerosis

Systemic sclerosis (SSc) is a connective tissue disease with a complex and multifactorial pathogenesis, characterized by excessive collagen deposition and vasculopathy, leading to skin fibrosis and involvement of internal organs. Regarding the aetiology of SSc, our current knowledge is still limited; however, as for other autoimmune syndromes, the disease is probably caused by both endogenous and exogenous factors. Among the exogenous factors, in the past decades, several environmental exposures, including occupational exposure to pollutants, chemicals and hand-arm vibrations as well as infections, silicone and use of drugs, have been suggested to play a role in the development of SSc. The following review analyzes the most recent literature to examine the relationship between environmental exposures and SSc.     

农村中学生精神卫生状况影响因素分析

目前，青少年心理健康问题日益受到重视，有关大、中学生的心理卫生调查研来已有不少报道’－‘。为了解农村中学生的精神卫生状况，寻找影响其心理健康的相关因素．并为预防心理疾病提供参考依据．我们对劲利县第七中学的中学生进行了调查。1资料及方法1．1对象选择我校高一至高三的学生，采取分层整群抽样方法，每年级抽取一个班共156人，男94人、女62人；一年级52人、二年级46人、三年级58人；年龄15～20岁·平均164士25岁。1·2方法采用症状自评量表（SCI，－90）［‘j和修订的艾森克个性问卷（EPQ）［’：；按指导语对每个学生进行…     

Immunomodulatory interplay of the microbiome and therapy of rheumatic diseases

Modulation of the immune system by microbes, especially from the gastrointestinal tract, is increasingly considered a key factor in the onset, course and outcome of rheumatic diseases. The interplay of the microbiome, along with genetic predisposition and environmental exposure, is thought to be an important trigger for rheumatic diseases. Improved identification of the relationship of disease-specific genetic alterations and rheumatic diseases has potential diagnostic and therapeutic applications. Treatment of rheumatic disorders is influenced by microbial actions but this interplay can be challenging due to variable and unpredictable responses to therapies. Expanded knowledge of the microbiome now allows clinicians to more precisely select ideal medication regimens and to predict response to and toxicity from drugs. Rheumatic diseases and associated therapies were among the earliest microbiome interactions investigated, yet it is notable that current research is focused on clinical and immunological associations but, in comparison, a limited number of studies regarding the microbiome’s impact on treatment for rheumatic diseases have been published. In the coming years, further knowledge of immunomodulating interactions between the microbiome and the immune system will aid our understanding of autoimmunity and will be increasingly important in selection of therapeutic agents for patients with autoimmune and rheumatic diseases. In this review, recent literature regarding the bidirectional immunomodulatory effects of the microbiome with rheumatic diseases and current understanding and gaps regarding the drug–microbiome interface in the management of these disorders is presented.     

Unintentional injuries in a twin study of preschool children: environmental, not genetic, risk factors

OBJECTIVE: To analyze the relative contribution of latent genetic and environmental factors to differences in the injury liability of children, and to examine the association between measured socio-economic, family, and child-behavior variables and unintentional injury risk. METHODS: Unintentional injuries from birth to age 5, together with information regarding measured risk variables, were reported by mothers in a sample of 1027 same-sex twin pairs from a nationally representative 1994-1995 birth cohort. RESULTS: Child-specific environmental factors accounted for most of the variance (86.4%) in the likelihood of ever having an injury. When considering the risk of two or more injuries child-specific environmental factors explained 60.2% of the variance and family-wide environmental influence 39.8%. Measured socio-economic, family, and child-behavior factors predicted frequent injury. CONCLUSIONS: Results give little support to the concept of a heritable injury-prone trait in preschool children; environmental influences accounted for most of the injury variance in this sample. However, behavioral variables, especially the child's externalizing problem behaviors, are also important in explaining unintentional injuries.     

Role of IL-10 gene polymorphisms on the susceptibility for esophageal cancer and its association with environmental factors

We conducted a hospital-based case-control study to investigate the association of three common SNPs (-1082G/A rs1800896, -819T/C rs1800871, and -592A/C rs1800872) of IL-10 gene polymorphisms with the susceptibility to esophageal cancer in a Chinese population. 246 patients with pathologically proven esophageal cancer and 492 healthy control subjects were collected in our study. Genotyping of IL-10-1082G/A rs1800896, -819T/C rs1800871, and -592A/C rs1800872 was performed using the Sequenom MassARRAY platform (Sequenom; San Diego, CA). Unconditional logistic regression analyses showed that subjects carrying the AA genotype and GA+AA genotype of IL-10-1082G/A rs1800896 were associated with an increased risk of esophageal cancer, and the adjusted ORs (95% CI) were 2.19 (1.31-3.64) and 1.44 (1.05-1.99), respectively. However, we did not find significant association of IL-10-819T/C rs1800871 and -592A/C rs1800872 with the development of esophageal cancer. By stratification analysis, we found that IL-10-1082G/A rs1800896 polymorphism has no significant association with smoking, drinking and family history of cancer in the first relatives in esophageal cancer risk (P>0.05). In conclusion, IL-10-1082G/A rs1800896 genetic variation may be employed as candidate biomarkers for the prediction of susceptibility in esophageal cancer.     

Analysis of the factors affecting the formation of the microbiome associated with chronic osteomyelitis of the jaw

Chronic osteomyelitis of the jaw (COMJ) is one of the most intractable diseases among head and neck infections. Antimicrobial agents are routinely administered for COMJ without sufficient bacterial information, resulting in frequent treatment failures. To improve our knowledge of the bacterial aetiology of COMJ and to assist in the development of effective treatments, we performed a comprehensive analysis of the microbiome. Sixteen patients with four clinical types of COMJ (four with suppurative osteomyelitis, three with osteoradionecrosis of the jaw, four with primary chronic osteomyelitis, and five with bisphosphonate-related osteonecrosis of the jaw) were enrolled in this study. Bone samples were subjected to bacterial community comparisons by 16S rRNA gene pyrosequencing. As a result, we clarified that COMJ was caused by a far greater range of bacterial species (12 phyla and 163 genera) than previously reported. Moreover, the bacterial structures in COMJ changed dramatically with disease stage and the condition of the affected bone. Multiple correlation analyses revealed that sequestration and bone exposure could affect the community structure. On the basis of these factors, we reclassified COMJ into three clinical stages: I, inflamed or sclerotic bone without exposure; II, sequestrum without exposure; and III, exposed sequestrum. In stage II, the bacterial diversity was significantly lower, and the anaerobe genera Fusobacterium, Tannerella (formerly Bacteroides) and Porphyromonas were more abundant, than observed during other stages. Because these bacteria habitually reside in any clinical stage, they were considered to constitute the core microbiome of COMJ. Targeting these bacteria should lead to the development of effective preventive measures and cures.     

Significance of indoor environment for the development of allergic symptoms in children followed up to 18 months of age

The development of symptoms possibly related to allergy or other forms of hypersensitivity was studied in a group of 638 children on two occasions: when the children were 3 and 18 months of age. Standardized questions were used to collect basic information about the child. technical characteristics of the home, and the mother's perception of the indoor climate. All reported exposure factors were analyzed in relation to the child's symptoms at 18 months of age, by logistic regression techniques. A family history of atopy was associated with a high incidence of most of the investigated symptoms. Attendance at a day nursery before 18 months of age increased the risk of recurrent colds and the need for several courses of treatment with antibiotics. If the mothers smoked, the children more often suffered from protracted coughing episodes. If the child had a sibling, the risk of developing a wheeze, repeated colds, and the need for antibiotic treatment increased. No building factors, such as size of the home, heating and ventilation system, type of foundation, dampness, or presence of wall-to-wall carpets, showed a significant correlation to symptoms reported in the children. However, if the mothers reported symptoms that are often connected with "sick buildings", the children more often had eczema, dry skin, or reactions to food. The mothers' complaints about indoor air quality and climatc and mucous membrane symptoms were significantly related to the type of building and presence of condensation on the windows in winter, a finding which may indicate that indoor climate factors also have some effect on the health of the children. This study reports the prevalences of symptoms until the age of 18 months. At this age, the allergic manifestations are usually nonspecific, and follow-up examinations to 4–5 years of age are needed before any definite conclusions can be drawn about the development of atopic diseases due to indoor climate factors.     

Localization, release and bioavailability of pollen allergens: the influence of environmental factors

Allergens are integral constituents of plants or animals and their normal functions and localization are being characterized. To trigger responses in humans, allergens must become bioavailable and the role of air pollutants--for example diesel-exhaust particles --in this process is causing concern. Finally, the fact that some pollen releases eicosanoid-like proinflammatory mediators may have wide implications.     

Study on the correlation between soil microbial diversity and ambient environmental factors influencing the safflower distribution in Xinjiang

The effects of soil microbial properties and physiographical factors on safflower distributions in the main safflower plantations of Xinjiang province in China were studied. This study may help determine the basis of the environmental factors for evaluating the geoherbalism of this medicinal plant. The soil microbial biodiversity in the bulk soil and rhizosphere of safflower at different growth stages and from different sampling plots were characterized by analyzing the environmental DNAs in the samples. With general primers targeting the 16S ribosomal DNA for bacteria and the internal transcribed spacer 1 gene for fungi, the study was performed using marker gene amplification coupled with Illumina HiSeq high-throughput sequencing technologies. Correlation analysis and a distance-based redundancy analysis were performed to determine the dominant factors affecting the distribution of the microorganism in safflower soils. A total of 16517 bacterial operational taxonomic units (OTUs) were obtained from all the 108 soil samples of nine safflower sampling plots. At the phylum level, 48 phyla have been identified with Actinobacteria (32.9%) and proteobacteria (28.7%) being predominant. For fungi, 8746 OTUs were obtained, which belonged to seven phyla with Ascomycota overwhelmingly superior in relative abundance. A significant positive correlation was found between soil microbe quantity and ASL (above sea level). Safflower was sensitive to changes in elevation, growing more abundantly in the mountainous regions at heights of around 1,200 m above sea level. It is concluded that the dominant factors affecting the distribution of microorganisms in safflower soils were soil moisture, available N, and ASL.     

复合环境因素诱导大鼠脑卒中机体防御基因表达的改变及意义

目的：探讨环境因素对脑卒中发生、发展的影响。方法：应用冷刺激加高盐饮食复合环境因素作用于Wistar大鼠，诱发大鼠高血压脑卒中作为模型，应用新近发展起来的抑制性消减杂交技术对卒中鼠和正常对照鼠脑的差异基因进行筛选。经过两轮杂交后，每组随机挑取288个克隆，进行测序及GenBank BLAST生物信息分析。结果：两组共有456个可用序列，我们对每个与已知基因高度同源的序列以功能为参照进行了分类，发现脑卒中时细胞与机体防御基因表达明显下调（P＜0．01），而与代谢相关基因（43个克隆与线粒体基因高度同源，P＜0．01）表达明显上调。结论：脑卒中时与应激相关的基因表达下调，说明机体的防御能力减弱。     

A primer on investigating the role of the microbiome in brain and cognitive development

Incorporating information regarding the gut microbiota into psychobiological research promises to shed new light on how individual differences in brain and cognitive development emerge. However, the investigation of the gut-brain axis in development is still in its infancy and poses several challenges, including data analysis. Considering that the gut microbiome is an eco-system containing millions of bacteria, one needs to utilize a breadth of methodologies and data analytic techniques. The present review serves two purposes. First, this review will inform developmental psychobiology researchers about the emerging study of the gut-brain axis in development and second, this review will propose methodologies and data analytic strategies for integrating microbiome data in developmental research.