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Background: Dysmenorrhea is a condition frequently affecting menstruating women worldwide. Unfortunately, only a few studies have estimated the relationship between alcohol consumption and dysmenorrhea among women. In particular, there are fewer studies to explore the association between alcohol consumption, dysmenorrhea, and age at menarche. Objective: This study aimed to evaluate whether and to what extent alcohol consumption is related to dysmenorrhea and age at menarche. Methods: This was a cross-sectional, observational study conducted among college students. A total of 3,837 participants (age ≥18 years) volunteered to participate in the study and completed the questionnaire. Moreover, 145 were excluded from the study owing to exclusion criteria. We divided female college students into two groups stratified by age at menarche (AAM) 13 years. Logistic regression models were performed to estimate odds ratios (OR) and 95% confidence intervals (CI) for the association of alcohol consumption with dysmenorrhea, adjusting for confounding factors. Results: A total of 3692 female college students completed the survey, including 409 (11.08%) who reported alcohol use. We found that alcohol consumption was not related to dysmenorrhea. However, stratified by age at menarche, we found that a positive association between alcohol consumption and dysmenorrhea among participants with AAM ≥13 years (OR,1.41; 95% CI, 1.06, 1.88). Compared with participants who reported no alcohol consumption, participants who reported consuming alcohol at least once a month (OR,1.29; 95% CI, 0.94, 1.78) and alcohol consumption at least once a week (OR,1.92; 95% CI, 1.07, 3.45) were more likely to have dysmenorrhea adjusting for other confounding factors. Conclusion: Our findings showed overall no association of alcohol consumption with dysmenorrhea but a statistically significant positive association for those whose AAM was >13 years.

Background Evidence supporting the definitive effect of alcohol consumption on dysmenorrhea has been sparse. The current study was aim to evaluate the relationship between alcohol consumption and dysmenorrhea among age-stratified female college students in northern China.Methods A total of 3692 female college students were included in this cross-sectional study. The logical regression model was performed to evaluate the association between alcohol consumption and primary dysmenorrhea. The model adjusted for confounding factors such as age and body mass index, and estimated the odds ratio (ORs) and 95% confidence interval (CIs).Results Multivariable-adjusted models showed the analysis stratified by age at menarche (AAM) revealed that the prevalence of dysmenorrhea in participants with AAM P = 0.003). Alcohol consumption showed a dose-response relationship with dysmenorrhea in participants with AAM ≥13 years old.Conclusion Our findings showed AAM modified the association of alcohol consumption with primary dysmenorrhea among female university students in North China.

OBJECTIVE: To investigate the optimal posterior screw placement and the geometry of safe zones for screw insertion in the talar neck. METHODS: Computed tomography data for 15 normal feet were imported into Mimics 10.01 software for 3‐dimensional reconstruction; 4.0‐mm‐diameter screws were simulated from the lateral tubercle of the posterior process of the talus to the talar head. The range of screw paths trajectories and screw lengths at nine locations that did not breach the cortex of the talus were evaluated. In addition, the farthest (point a) and nearest point (point b) of the safe zone to the subtalar joint at each location, the anteversion angle (angle A), which is parallel to the sagittal plane, and the horizontal angle (angle B), which is perpendicular to the sagittal plane, were measured. RESULTS: The safe zone was mainly between the 30% location and the 60% location; the width of each safe zone was 13.6° ± 1.4°; the maximum height of each safe zone was 7.8° ± 1.2°. The height of the safe zone was lowest at the 30% location (4.5°) and highest at the 50% location (7.3°). The mixed safe zone of all tali was between the 50% location and the 60% location. When a screw was inserted at point a, the safe entry distance (screw length) ranged from 48.8 to 49.5 mm, and when inserted to point b, the distance ranged from 48.2 to 48.9 mm. And inserting a 48.7 mm screw, 5.6° laterally and 7.4° superiorly, from the lateral tubercle of the posterior process of the talus towards the talar head is safest. CONCLUSION: The safe zone of posterior screw fixation have been defined applying to most talus, assuming the fractures are well reduced, this may strengthen the stability, shorten the operation time and reduce the incidence of surgical complications.

Background: Genetic polymorphisms of TP63 have been suggested to influence susceptibility to lung adenocarcinoma development in East Asian populations. This study aimed to investigate the relationship between common polymorphisms in the TP63 gene and the risk of lung adenocarcinoma, as well as interactions of the polymorphisms with environmental risk factors in Chinese non-smoking females. Methods: A case-control study of 260 cases and 318 controls was conducted. Data concerning demographic and risk factors were obtained for each subject. The genetic polymorphisms were determined by Taqman real-time PCR and statistical analyses were performed using SPSS software. Results: For 10937405, carriers of the CT genotype or at least one T allele (CT/TT) had lower risks of lung adenocarcinoma compared with the homozygous wild CC genotype in Chinese nonsmoking females (adjusted ORs were 0.68 and 0.69, 95%CIs were 0.48-0.97 and 0.50-0.97, P values were 0.033 and 0.030, respectively). Allele comparison showed that the T allele of rs10937405 was associated with a decreased risk of lung adenocarcinoma with an OR of 0.78 (95%CI=0.60-1.01, P=0.059). Our results showed that exposure to cooking oil fumes was associated with increased risk of lung adenocarcinoma in Chinese nonsmoking females (adjusted OR=1.58, 95%CI=1.11-2.25, P=0.011). However, we did not observe a significant interaction of cooking oil fumes and TP63 polymorphisms. Conclusion: TP63 polymorphism might be a genetic susceptibility factor for lung adenocarcinoma in Chinese non-smoking females, but no significant interaction was found with cooking oil fume exposure.

Background: Concentrations of ambient air pollution and pollutants in China have changed considerably during the last decade. However, few studies have evaluated the effects of current ambient air pollution on the health of kindergarten children. Methods: We studied 6730 Chinese children (age, 3–7 years) from 50 kindergartens in 7 cities of Northeast China in 2009. Parents or guardians completed questionnaires that asked about the children’s histories of respiratory symptoms and risk factors. Three-year concentrations of particles with an aerodynamic diameter ≤10µm (PM10), sulfur dioxide (SO2), and nitrogen dioxides (NO2) were calculated at monitoring stations in 25 study districts. A 2-stage regression approach was used in data analyses. Results: The prevalence of respiratory symptoms was higher among children living near a busy road, those living near chimneys or a factory, those having a coal-burning device, those living with smokers, and those living in a home that had been recently renovated. Among girls, PM10 was associated with persistent cough (odds ratio [OR]PM10 = 1.44; 95% CI, 1.18–1.77), persistent phlegm (ORPM10 = 1.36; 95% CI, 1.02–1.81), and wheezing (ORPM10 = 1.31; 95% CI, 1.04–1.65). NO2 concentration was associated with increased prevalence of allergic rhinitis (OR = 1.96; 95% CI, 1.27–3.02) among girls. In contrast, associations of respiratory symptoms with concentrations of PM10 ,S O2, and NO2 were not statistically significant among boys. Conclusions: Air pollution is particularly important in the development of respiratory morbidity among children. Girls may be more susceptible than boys to air pollution.

Although extremity chronic osteomyelitis is common in China, updated data were still limited regarding its characterizations. The present study aimed to review clinical features of extremity chronic osteomyelitis in Southern China. A retrospective analysis was conducted in the patients who had sought medical attention from January 2010 to April 2015 for extremity chronic osteomyelitis in Nanfang Hospital in Southern China. Clinical data were collected and analyzed. A total of 394 patients (307 males and 87 females) were included, giving a gender ratio of 3.53. The median age at first diagnosis was 42 years for all. The most frequent type was traumatic osteomyelitis (262 cases, 66.50%), which was mainly caused by open injury (166 cases, 63.36%) and during a road accident (91 cases, 34.73%). Single-site infection accounted for 81.98% (323 cases), with tibia (126 cases), femur (79 cases), calcaneus (37 cases), and toes (37 cases) as the top sites. The positive rate of intraoperative culture was 70.63% (214/303), 78.97% (169/214) of which was monomicrobial infection. Staphylococcus aureus (59 cases) was the most frequent bacteria for monomicrobial infection, followed by Pseudomonas aeruginosa (29 cases) and Escherichia coli (11 cases). The positive ratios of preoperative serum white blood cell (WBC), erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), procalcitonin (PCT), interleukin-6 (IL-6), and tumor necrosis factor alpha (TNF-α) were 21.63%, 64.92%, 53.27%, 42.25%, 72.82%, and 66.67%, respectively. The most frequently used intravenous antibiotic was cephalosporins. The overall cure rate was 77.74%, with a total amputation rate of 16.75%. In this representative Chinese cohort, extremity chronic osteomyelitis was mostly caused by open injury and during a road accident, predominated in males and favored the tibia. S. aureus was the most frequent pathogenic organism. Preoperative elevated levels of serum IL-6, TNF-α, and ESR may be helpful diagnostic indicators of the disease. Most patients achieved a favorable clinical efficacy after appropriate treatment.

Background and Aims This study was carried out to assess and investigate the prevalence of overweight and obesity among preschool-age children living in northeast China using the World Health Organization (WHO), International Obesity Task Force (IOTF) and Centers for Disease Control and Prevention (CDC) standard criteria and to explore the differences in estimates by using the three reference standards. Methods We used data from 8,653 preschool children with an average age of 5.02 years. Weight and height were obtained for each child and body mass index (BMI) was calculated. The prevalence of overweight and obesity was then determined using the CDC, IOTF and WHO guidelines. Results According to the IOTF reference, 10.98% of the children were overweight and 6.08% were obese. The CDC reference classified 11.27% as overweight and 11.72% as obese. However, with the WHO reference, 10.93% were overweight and 13.81% were obese. There was significant gender difference in the prevalence of overweight and obesity based on the CDC and WHO references. According to age classification, differences in the frequencies of obesity in both boys and girls reached statistical significance using the three references, and the differences were gradually improved from the WHO to CDC and IOTF cut-off points. In this study, the WHO and the CDC references demonstrated a high level of agreement (kappa = 0.89). Conclusions The results indicate overweight and obesity prevalence among preschool children in northeast China is comparable to some Western countries. The WHO reported a much higher prevalence of obesity compared to other references. Age, gender and method differences in the prevalence of overweight and obesity suggested a systematic evaluation of the preschool children in China.

To assess the interaction of environmental tobacco smoke (ETS) exposure and allergic predisposition regarding respiratory health among Chinese children, a sample of 23,474 children (6-13 years old) was studied from 25 districts in Liaoning province, China. The results showed that children without allergic predisposition were more susceptible to ETS than children with allergic predisposition. Among children without allergic predisposition, ETS exposure was associated with more respiratory symptoms and diseases in boys than in girls; In utero ETS exposure was associated with history of asthma (OR, 1.86; 95% CI, 1.44-2.40) and current asthma (OR, 2.25; 95% CI, 1.48-3.44) only among boys without allergic predisposition. Among children with allergic predisposition, more associations between ETS exposure and respiratory symptoms and diseases were detected in girls. In conclusion, ETS exposure was more evident in boys without family atopy history and more associations were detected in girls with family atopy history.

Background Very few studies have assessed the relative impact of housing characteristics and home environmental factors on asthma and asthma-related symptoms in Chinese children who have lower rates of asthma. To our knowledge few studies have assessed respiratory symptoms and allergies in this context. Methods To assess the effects of housing characteristics, pet keeping, home decorations and other indoor environmental factors on respiratory health of Chinese children. We studied a population of 14,729 children (1–13 years old) from 12 districts in Liaoning province, Northeast China. Information on respiratory health, housing characteristics, and environmental pollutions were obtained by a standard questionnaire from the American Thoracic Society. Results Housing conditions, house adjacent to traffic or not, house with or without pollution source nearby, pet keeping, presence of pests and mold/water damage in the home, home decorations and exposure to environmental tobacco smoke (ETS) were associated with doctor-diagnosed asthma and asthma-related symptoms both in boys and girls. The vulnerability towards exposure to housing conditions and environmental factors differed between males and females. Among boys, the risk of respiratory morbidity appeared to be reduced in households with larger surface areas and more rooms; use of a ventilation device was strongly protective against persistent phlegm (OR = 0.68; 95%CI: 0.48, 0.96). Asthma-related symptoms were more associated with different pets among girls than among boys. The presence of a cat in the household was associated with doctor-diagnosed asthma (OR = 1.89; 95% CI, 1.11–3.20), current wheeze (OR = 2.64; 95% CI, 1.52–4.59), persistent cough (OR = 1.84; 95% CI, 1.18–2.87) and persistent phlegm (OR = 2.17; 95% CI, 1.21–3.87) only among girls. Conclusion Living within the vicinity of a source of pollution, traffic, pet keeping, home decorations, pests, mold and ETS are important determinants of children's respiratory health in China.

Background: Only few studies have assessed the relative impact of housing characteristics and home environmental factors on asthma and asthma-related symptoms in Chinese children, and to our knowledge, few studies have elaborated respiratory symptoms and allergies in this context. Objective: It was the aim of this study to assess the effects of housing characteristics, pet keeping, home decorations and other indoor environmental factors on respiratory health of Chinese children. Methods: We studied 10,784 children (6–13 years old) from 12 districts in Liaoning province, Northeast China. Information on respiratory health, housing characteristics and environmental pollution was obtained by a standard questionnaire from the American Thoracic Society. Results: Prevalence of asthma-related symptoms was higher for those living along the main stem of traffic, and for those with a house nearby a pollution source. Lower prevalence rates of respiratory morbidity were associated with households with a bigger area of residence and more rooms. Pet keeping was associated with doctor-diagnosed asthma (OR = 1.52; 95% CI 1.25–1.84). Home decorations also increased the risk of doctor-diagnosed asthma (OR = 1.72; 95% CI 1.45–2.04) and current asthma (OR = 1.43; 95% CI 1.06–1.93). Environmental tobacco smoke, pests and visible mold on walls were associated with the occurrence of asthma symptoms. Conclusion: Home environmental factors are particularly important for the development of respiratory morbidity among children.

Background MicroRNAs play important roles in the development of human chronic diseases including lung cancer. This is the first case-control study of lung cancer in a non-smoking female population in northeast China, to evaluate the roles of the polymorphisms in pre-miRNAs on risk of lung cancer. Methods The genotypes of six polymorphisms in miRNAs were determined in 575 patients with lung cancer and 608 healthy controls who were frequency matched for age. Results For miR-146a rs2910164, individuals carrying heterozygous CG or homozygous GG genotype had decreased risks of lung cancer compared with those carrying homozygous wild CC genotype (adjusted odds ratios were 0.76 and 0.64, 95% confidence intervals were 0.59–0.99 and 0.46–0.90, P values were 0.039 and 0.010, respectively). G allele of rs2910164 was associated with a lower risk of lung cancer with a significant odds ratio of 0.80. MiR-423 rs6505162CA or AA genotype was associated with significantly decreased risk for lung cancer compared to CC genotype (adjusted odds ratios were 0.77 and 0.54). The significant result was also found in the allele model with odds ratio of 0.75. However, miR-196a2 rs11614913, miR-30c-1 rs928508, miR-608 rs4919510 and miR-27a rs895819 polymorphisms were not significantly associated with lung cancer risks in any models. The similar results were also found in lung adenocarcinoma patients. Conclusions These findings suggest that miR-146a rs2910164C>G and miR-423 rs6505162C>A polymorphisms may contribute to genetic susceptibility to lung cancer and lung adenocarcinoma in Chinese non-smoking females.

To study the effects of indoor air pollution and individual susceptible factors on prevalence of children's asthma and asthma-related symptoms in Shenyang city.On April, 2007, 8733 Han children who were under age of 12 and lived for more than 2 years in Shenyang city, were selected from five administrative areas (one primary school and two kindergartens for each area) through cluster random sampling method. Information on children's general condition, asthma and related symptoms (including stridor, stridor symptoms, persistent cough, persistent phlegm), indoor air pollution, and susceptibility history were obtained by a standard questionnaire from the American Thoracic Society. The effects of indoor air pollution on asthma and asthma-related symptoms was analyzed through χ(2) test. Logistic regression was used to research the effects of risk factors on the prevalence of asthma and asthma-related symptoms of both susceptible and non-susceptible children.Among the 8733 subjects, 4420 (50.6%) were boy and 4313 (49.4%) were girl, with the age of (8.08 ± 2.88) years old. The prevalence of asthma, current asthma, cough, persistent phlegm, stridor and stridor symptom were 6.4% (559 cases), 2.5% (215 cases), 9.6% (836 cases), 4.4% (386 cases), 17.5% (1524 cases) and 2.6% (229 cases) respectively. The prevalence of asthma the boys and girls were among 7.1% (313 cases) and 5.7% (246 cases) (χ(2) = 6.916, P0.05); and stridor symptom for them were 19.2% (850 cases), 15.6% (674 cases) (χ(2) = 19.678, P0.05), respectively. Passive smoking before two years old, house decoration and pet were related to asthma of children, and there was significant difference between the two groups. The prevalence of asthma of exposed children were 7.7% (312 cases), 9.5% (159 cases), 8.0% (270 cases), 9.0% (114 cases), respectively. Compared with the non-exposed children who had asthma, the prevalence of asthma were 5.7% (400 cases), 5.4% (289 cases), 6.0% (445 cases), the value of χ(2) were 33.646, 23.944 and 16.527 respectively (all P values0.05). Children who had family history of asthma, family history of allergy and allergy history were also related with asthma, the prevalence of asthma were 17.3% (106 cases), 13.1% (85 cases), 22.0% (147 cases), compared with the non-exposed children who had asthma, the prevalence of asthma were 5.5% (453), 5.9% (474), 5.1% (412), and there was significant difference between the two groups, the value of χ(2) were 130.522, 59.929 and 293.997, respectively (all P values0.05). Logistic regression analysis showed that passive smoking (OR = 1.7, 95%CI: 1.2 - 2.4), house decoration (OR = 1.5, 95%CI: 1.1 - 1.9) and pet (OR = 1.6, 95%CI: 1.1 - 2.3) were statistically significant to asthma in non-susceptible children. While passive smoking (OR = 1.3, 95%CI: 1.0 - 1.7) and house decoration (OR = 1.4, 95%CI: 1.1 - 1.7) were increased the risk of asthma.Indoor air pollution is a risk factor of children' s asthma. Family history of asthma and physical susceptible children are high risk to asthma, and susceptible children are easily influenced by other risk factors.

BackgroundThere have been few published studies on spirometric reference values for healthy children in China. We hypothesize that there would have been changes in lung function that would not have been precisely predicted by the existing spirometric reference equations. The objective of the study was to develop more accurate predictive equations for spirometric reference values for children aged 9 to 15 years in Northeast China.Methodology/principal findingsSpirometric measurements were obtained from 3,922 children, including 1,974 boys and 1,948 girls, who were randomly selected from five cities of Liaoning province, Northeast China, using the ATS (American Thoracic Society) and ERS (European Respiratory Society) standards. The data was then randomly split into a training subset containing 2078 cases and a validation subset containing 1844 cases. Predictive equations used multiple linear regression techniques with three predictor variables: height, age and weight. Model goodness of fit was examined using the coefficient of determination or the R(2) and adjusted R(2). The predicted values were compared with those obtained from the existing spirometric reference equations. The results showed the prediction equations using linear regression analysis performed well for most spirometric parameters. Paired t-tests were used to compare the predicted values obtained from the developed and existing spirometric reference equations based on the validation subset. The t-test for males was not statistically significant (p>0.01). The predictive accuracy of the developed equations was higher than the existing equations and the predictive ability of the model was also validated.Conclusion/significanceWe developed prediction equations using linear regression analysis of spirometric parameters for children aged 9-15 years in Northeast China. These equations represent the first attempt at predicting lung function for Chinese children following the ATS/ERS Task Force 2005 guidelines on spirometry standardization.

In vitro and in vivo studies have demonstrated that lung cell apoptosis is associated with lung fibrosis; however the relationship between apoptosis of alveolar macrophages (AMs) and human silicosis has not been addressed. In the present study, AM apoptosis was determined in whole-lung lavage fluid from 48 male silicosis patients, 13 male observers, and 13 male healthy volunteers. The relationships between apoptosis index (AI) and silica exposure history, soluble Fas (sFas)/membrane-bound Fas (mFas), and caspase-3/caspase-8 were analyzed. AI, mFas, and caspase-3 were significantly higher in lung lavage fluids from silicosis patients than those of observers or healthy volunteers, but the level of sFas demonstrated a decreasing trend. AI was related to silica exposure, upregulation of mFas, and activation of caspase-3 and -8, as well as influenced by smoking status after adjusting for confounding factors. These results indicate that AM apoptosis could be used as a potential biomarker for human silicosis, and the Fas/FasL pathway may regulate this process. The present data from human lung lavage samples may help to understand the mechanism of silicosis and in turn lead to strategies for preventing or treating this disease.

Previous studies indicate that exposure to perfluorooctanesulfonate (PFOS), a ubiquitous and highly persistent environmental contaminant, induces immunotoxicity in mice. However, few studies have specifically assessed the effects of PFOS on inflammation. This study utilized a standard 60-day oral exposure period to assess the effects of PFOS on the response of inflammatory cytokines [tumor necrosis factor α (TNF-α), interleukin-1 β (IL-1β), and interleukin-6 (IL-6)]. Adult male C57BL/6 mice were dosed daily by oral gavage with PFOS at 0, 0.0083, 0.0167, 0.0833, 0.4167, 0.8333 or 2.0833 mg/kg/day to yield a targeted Total Administered Dose (TAD) over 60 days of 0, 0.5, 1, 5, 25, 50, or 125 mg PFOS/kg, respectively. The percentage of peritoneal macrophages (CD11b+ cells) was significantly increased at concentrations ≥ 1 mg PFOS/kg TAD in a dose-dependent manner. Ex vivo IL-1β production by peritoneal macrophages was elevated substantially at concentrations of ≥ 5 mg PFOS/kg TAD. Moreover, PFOS exposure markedly enhanced the ex vivo production of TNF-α, IL-1β and IL-6 by peritoneal and splenic macrophages when stimulated either in vitro or in vivo with lipopolysaccharide (LPS). The serum levels of these inflammatory cytokines observed in response to in vivo stimulation with LPS were elevated substantially by exposure to PFOS. PFOS exposure elevated the expression of pro-inflammatory cytokines TNF-α, IL-1β, IL-6, and proto-oncogene, c-myc, in the spleen. These data suggest that exposure to PFOS modulates the inflammatory response, and further research is needed to determine the mechanism of action.

Background: Experimental data suggest that asthma exacerbation by allergens is enhanced by exposure to environmental tobacco smoke (ETS); however, there is little supporting epidemiologic evidence. To our knowledge, few studies have assessed respiratory symptoms and allergies in this context. Objectives: To evaluate whether the association of exposure to animals (indicators of allergen and endotoxin exposure) with asthma-related symptoms is modified by ETS exposure in Chinese children. Methods: A cross-sectional study of 8,819 children in kindergarten was conducted in 25 districts in northern China. Information on respiratory health and exposure to indoor allergens was obtained using a standard questionnaire from the American Thoracic Society. Results: Among the children with ETS exposure in utero, the effects of exposure to animals were significant with respect to persistent cough [adjusted odds ratio (OR) 1.83; 95% confidence interval (CI) 1.12–2.99] and persistent phlegm (adjusted OR 2.40; 95% CI 1.28–4.54). The combined effect of in utero ETS exposure and animal exposure on doctor-diagnosed asthma was approximately as expected on the basis of their independent effects on an additive scale. There was no interaction between animal exposure and ETS exposure in the first 2 years of life or current ETS exposure. Conclusions: This study provides evidence that animal and ETS exposure increases the risk of asthma-related symptoms in children in kindergarten. ETS exposure in utero did modify the effect of animal exposure on persistent phlegm and persistent cough but not on doctor-diagnosed asthma among children.

Background: Silicosis is an occupational lung disease caused by inhalation of silica dust characterized by lung inflammation and fibrosis. Previous study showed that Th1 and Th2 cytokines are involved in silicosis, but Th1/Th2 polarization during the development of silicosis is still a matter of debate. Regulatory T cells (Treg cells) represent a crucial role in modulation of immune homeostasis by regulating Th1/Th2 polarization, but their possible implication in silicosis remains to be explored. Methodology/Principal Findings: To evaluate the implication of Treg cells in the development of silicosis, we generated the Treg-depleted mice model by administration of anti-CD25 mAbs and mice were exposed to silica by intratracheal instillation to establish experimental model of silica-induced lung fibrosis. The pathologic examinations show that the Treg-depleted mice are susceptive to severer inflammation in the early stage, with enhanced infiltration of inflammatory cells. Also, depletion of Treg cells causes a delay of the progress of silica-induced lung fibrosis in mice model. Further study of mRNA expression of cytokines reveals that depletion of Tregs leads to the increased production of Th1-cytokines and decreased production of Th2-cytokine. The Flow Cytometry and realtime PCR study show that Treg cells exert the modulation function both directly by expressing CTLA-4 at the inflammatory stage, and indirectly by secreting increasing amount of IL-10 and TGF-b during the fibrotic stage in silica-induced lung fibrosis. Conclusion/Significance: Our study suggests that depletion of Tregs may attenuate the progress of silica-induced lung fibrosis and enhance Th1 response and decelerate Th1/Th2 balance toward a Th2 phenotype in silica-induced lung fibrosis. The regulatory function of Treg cells may depend on direct mechanism and indirect mechanism during the inflammatory stage of silicosis.

A paucity of data exists to corroborate the few studies that report immune suppression after exposure to perfluorooctanesulfonate (PFOS). In this study, adult male C57BL/6 mice were exposed to PFOS daily via gavage for 60 days [0, 0.5, 5, 25, 50, or 125 mg/kg total administered dose (TAD)]. The results showed that liver mass was significantly increased ator =5 mg PFOS/kg TAD and in a dose-dependent manner. Lymphocyte proliferation and natural killer cell activity were altered in male mice. Plaque forming cell (PFC) response was suppressed beginning at 5 mg/kg TAD. Based on the liver mass and PFC response, the no observed adverse effect level and lowest observed adverse effect level for male mice exposed PFOS for 60 days was 0.5 and 5 mg/kg TAD, respectively. Measured PFOS serum concentrations at these dose levels were 0.674 +/- 0.166 and 7.132 +/- 1.039 mg/l, respectively. These results indicate that PFOS exposure can affect the immunity function in mice at levels approximately 50-fold for highly exposed human populations.