Vaping Behavior and Intention to Quit among Undergraduate Students in a Hispanic-Serving University

The surge in electronic nicotine delivery systems (ENDS) usage, particularly among young adults, poses significant public health concerns. This study aimed to identify predictors of e-cigarette use, quit attempts, and frequency among undergraduate students in a Hispanic-serving university in Texas. A cross-sectional study was conducted between August 1 and October 26, 2023, recruiting undergraduate students through the Sona system, an online experiment management platform. Participants completed an online survey that covered demographics, educational status, vaping status, initiation age, reasons for first and current e-cigarette use, frequency of past usage, intentions to quit, and quit attempt frequency. Statistical analysis included descriptive statistics, multinomial logistic regression, and multivariable linear regression. Among 316 participants, 33.9% reported current e-cigarette use. Junior and senior students, as well as prior tobacco users, were more likely to be current vapers. Prior vaping experience was more prevalent among Hispanic individuals and those with a history of tobacco use. Notably, 74.3% of current users attempted to quit in the past year, with a higher frequency of quit attempts among females, Hispanic students, and those with vaping acquaintances. However, the vaping behavior and quit attempt patterns were similar across other categories. This study highlights how various factors influence e-cigarette use among college students. It suggests that prevention and quitting programs should consider the specific needs of different groups. Future studies will continue to look at different student groups to find the most effective ways to help them quit vaping.

Association of arsenic exposure with measles antibody titers in US children: Influence of sex and serum folate levels

Exposure to arsenic during childhood is associated with various adverse health conditions. However, little is known about the effect of arsenic exposure on vaccine-related humoral immunity in children. We analyzed data from the National Health and Nutrition Examination Survey (2003-2004 and 2009-2010) to study the relationship between urinary arsenic and measles antibody levels in 476 US children aged 6-11. Multivariable linear regression was used to evaluate the association, adjusting for cycle, age, race, body mass index (BMI), serum cotinine, poverty index ratio, and vitamin B12 and selenium intakes. Stratified analyses were conducted by sex and serum folate levels using the median as cutoff (18.7 ng/mL). The measles antibody concentrations in the 3rd and 4th quartiles were found to have significantly decreased by 28.5 % (95 % Confidence Interval (CI) -47.6, -2.28) and 36.8 % (95 % CI -50.2, -19.5), compared to the lowest quartile among boys with serum folate levels lower than 18.7 ng/ml. The serum measles antibody titers significantly decreased by 16.7 % (95 %CI -25.0, -7.61) for each doubling of creatinine-corrected urinary total inorganic arsenic concentrations in the same group. No associations were found in boys with high serum folate levels or in girls. Further prospective studies are needed to validate these findings and develop interventions to protect children from infectious diseases.

Association between e-cigarette use and asthma among US adolescents: Youth Risk Behavior Surveillance System 2015-2019

BACKGROUND

Previous studies have suggested that e-cigarette use, which has increased rapidly among US adolescents, may cause respiratory distress. This cross-sectional study aimed to investigate the factors associated with e-cigarette use and the relationship between e-cigarette use and asthma among US adolescents.

METHODS

Data from the Youth Risk Behavior Surveillance System between 2015 and 2019 were analyzed, and multivariable logistic regression was used to identify demographic and behavioral factors associated with e-cigarette use. Stratified analyses were conducted to assess the relationship between e-cigarette use and asthma among adolescents by previous combustible product use.

RESULTS

This study found that Hispanic adolescents had lower odds of e-cigarette use than White adolescents in Texas, with factors such as age, substance use, and depression being associated with use. In the US, male gender, previous combustible and substance use, and depression were associated with higher odds of ever using e-cigarettes, while current use was associated with several factors including age and White race. E-cigarette use was significantly associated with asthma among adolescents who have never used combustible products in both Texas and the entire US after adjusting for covariates (OR 1.32, 95% CI 1.06-1.66 and OR 1.18, 95% CI 1.02-1.37, respectively).

CONCLUSION

The findings from this study can be used to inform public health strategies and policies aimed at reducing e-cigarette use and its associated health risks among adolescents.

Examining workweek variations in computer usage patterns: An application of ergonomic monitoring software

Alternative work arrangements have emerged as potential solutions to enhance productivity and work-life balance. However, accurate and objective measurement of work patterns is essential to make decisions about adjusting work arrangements. This study aimed at evaluating objective computer usage metrics as a proxy for productivity using RSIGuard, an ergonomics monitoring software. Data were collected from 789 office-based employees over a two-year period between January 1, 2017 and December 31, 2018 at a large energy company in Texas. A generalized mixed-effects model was utilized to compare computer usage patterns across different days of the week and times of the day. Our findings demonstrate that computer output metrics significantly decrease on Fridays compared to other weekdays, even after controlling for total active hours. Additionally, we found that workers' output varied depending on the time of day, with reduced computer usage observed in the afternoons and a significant decrease on Friday afternoons. The decrease in the number of typos was much less than that in the number of words typed, indicating reduced work efficiency on Friday afternoons. These objective indicators provide a novel approach to evaluating the productivity during the workweek and can help optimize work arrangements to promote sustainability for the benefit of employers, employees, and the environment.

The contribution of secondhand tobacco smoke to blood lead levels in US children and adolescents: a cross-sectional analysis of NHANES 2015-2018

BACKGROUND

Lead is a major developmental neurotoxicant in children, and tobacco smoke has been suggested as a source of lead exposure in vulnerable populations. This study evaluates the contribution of secondhand tobacco smoke (SHS) to blood lead levels (BLLs) in children and adolescents.

METHODS

We analyze data from 2,815 participants aged 6-19 years who participated in the National Health and Nutrition Examination Survey (2015-2018) to investigate the association between serum cotinine levels and BLLs. A multivariate linear regression was conducted to estimate geometric means (GMs) and the ratios of GMs after adjusting for all covariates.

RESULTS

The geometric means of BLLs in study participants aged 6 - 19 years were 0.46 µg/dl (95% CI 0.44, 0.49). After adjusting for relevant participant characteristics, the geometric means of BLLs were 18% (BLL 0.48 µg/dl, 95% CI 0.45, 0.51) and 29% (BLL 0.52 µg/dl, 95% CI 0.46, 0.59) higher in participants who had intermediate serum cotinine levels (0.03 - 3 ng/mL) and those who had high serum cotinine levels (> 3 ng/mL) respectively, compared to participants who had low serum cotinine levels (BLL 0.41 µg/dl, 95% CI 0.38, 0.43).

CONCLUSIONS

SHS exposure may be a source of BLLs in US children and adolescents. Efforts to reduce lead exposure in children and adolescents should include strategies to reduce SHS exposure.

Characterization of Arsenic and Atrazine Contaminations in Drinking Water in Iowa: A Public Health Concern

Arsenic and atrazine are two water contaminants of high public health concern in Iowa. The occurrence of arsenic and atrazine in drinking water from Iowa's private wells and public water systems was investigated over several decades. In this study, the percentages of detection and violation of regulations were compared over region, season, and water source, and factors affecting the detection and concentration of arsenic and atrazine were analyzed using a mixed-effects model. Atrazine contamination in drinking water was found to vary by region, depending on agricultural usage patterns and hydrogeological features. The annual median atrazine levels of all public water systems were below the drinking water standard of 3 ppb in 2001-2014. Around 40% of public water systems contained arsenic at levels > 1 ppb in 2014, with 13.8% containing arsenic at levels of 5-10 ppb and 2.6% exceeding 10 ppb. This unexpected result highlights the ongoing public health threat posed by arsenic in drinking water in Iowa, emphasizing the need for continued monitoring and mitigation efforts to reduce exposure and associated health risks. Additionally, an atrazine metabolite, desethylatrazine, should be monitored to obtain a complete account of atrazine exposure and possible health effects.

Comparative Biomonitoring of Arsenic Exposure in Mothers and Their Neonates in Comarca Lagunera, Mexico

Multiple comorbidities related to arsenic exposure through drinking water continue to be public problems worldwide, principally in chronically exposed populations, such as those in the Comarca Lagunera (CL), Mexico. In addition, this relationship could be exacerbated by an early life exposure through the placenta and later through breast milk. This study conducted a comparative analysis of arsenic levels in multiple biological samples from pregnant women and their neonates in the CL and the comparison region, Saltillo. Total arsenic levels in placenta, breast milk, blood, and urine were measured in pregnant women and their neonates from rural areas of seven municipalities of the CL using atomic absorption spectrophotometry with hydride generation methodology. The average concentrations of tAs in drinking water were 47.7 µg/L and 0.05 µg/L in the exposed and non-exposed areas, respectively. Mean levels of tAs were 7.80 µg/kg, 77.04 µg/g-Cr, and 4.30 µg/L in placenta, blood, urine, and breast milk, respectively, in mothers, and 107.92 µg/g-Cr in neonates in the exposed group, which were significantly higher than those in the non-exposed area. High levels of urinary arsenic in neonates were maintained 4 days after birth, demonstrating an early arsenic exposure route through the placenta and breast milk. In addition, our study suggested that breastfeeding may reduce arsenic exposure in infants in arsenic-contaminated areas. Further studies are necessary to follow up on comorbidities later in life in neonates and to provide interventions in this region.

A Systems Approach to Remediating Human Exposure to Arsenic and Fluoride From Overexploited Aquifers

In semiarid agricultural regions, aquifers have watered widespread economic development. Falling water tables, however, drive up energy costs and can make the water toxic for human consumption. The study area is located in central Mexico, where arsenic and fluoride are widely present at toxic concentrations in well water. We simulated the holistic outcomes from three pumping scenarios over 100 years (2020-2120); (S1) pumping rates increase at a similar rate to the past 40 years, (S2) remain constant, or (S3) decrease. Under scenario S1, by 2120, the depth to water table increased to 426 m and energy consumption for irrigation increased to 4 × 10⁹ kWh/yr. Arsenic and fluoride concentrations increased from 14 to 46 μg/L and 1.0 to 3.6 mg/L, respectively. The combined estimated IQ point decrements from drinking untreated well water lowered expected incomes in 2120 by 27% compared to what they would be with negligible exposure levels. We calculated the 100-year Net Present Value (NPV) of each scenario assuming the 2020 average crop value to water footprint ratio of 0.12 USD/m³. Without drinking water mitigation, S1 and S3 yielded relative NPVs of -5.96 × 10⁹ and 1.51 × 10⁹ USD, respectively, compared to the base case (S2). The relative NPV of providing blanket reverse osmosis treatment, while keeping pumping constant (S2), was 11.55 × 10⁹ USD and this gain increased when combined with decreased pumping (S3). If a high value, low water footprint crop was substituted (broccoli, 1.51 USD/m³), the net gains from increasing pumping were similar in size to those of implementing blanket drinking water treatment.

Evaluation of Healthy South Texas Asthma Program on improving health outcomes and reducing health disparities among the underserved Hispanic population: using the RE-AIM model

Background

In the United States, childhood asthma prevalence is higher among low-income communities and Hispanic populations. Previous studies found that asthma education could improve health and quality of life, especially in vulnerable populations lacking healthcare access. This study aims to describe Healthy South Texas Asthma Program (HSTAP), an evidence-based asthma education and environmental modification program in South Texas, and evaluate its associations with health-related outcomes among Hispanic children with asthma and their families.

Methods

The RE-AIM (Reach, Effectiveness, Adoption, Implementation, Maintenance) planning and evaluation framework was used as an overarching tool to evaluate the impact of the HSTAP. This educational program included 451 children with asthma and their families living in South Texas, an impoverished area at the Texas-Mexico border. The program consisted of (a) the asthma education (2-h) for children with asthma provided by Respiratory Therapy students at the children’s schools and (b) the home visit Asthma and Healthy Homes education and walk-through sessions (at baseline and 3 months) for parents and two follow-up visits (6 and 9–12 months later) led by community health workers. The education was provided in either English or Spanish between September 2015 and August 2020 as part of the Healthy South Texas Initiative. A pre-and post-test design was implemented to assess the differences in health outcomes, knowledge, and behaviors using standardized self-reported surveys as reported by parents. Analyses included primary descriptive analyses, generalized estimating equation models, the Wilcoxon signed-rank test, and the McNemar test.

Results

The HSTAP was significantly associated with improved individual-level outcomes on the frequency of asthma-related respiratory symptoms, including shortness of breath, chest tightness, coughing, and sleep difficulty, among children with asthma, as well as an enhanced asthma knowledge in their family. This study also showed significant associations with children’s school attendance and participation in physical activities and family social events and decreased families’ worry about their asthma management.

Conclusions

The RE-AIM model was a helpful framework to assess the HSTAP on all its components. The results suggest that participation in an asthma education and environmental modification program was associated with improved individual-level health conditions and reduced health disparities among children with asthma in low-income communities.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12887-021-02991-8.

Utilization and outcomes of metastasectomy for patients with metastatic urothelial cancer: An analysis of the national cancer database

BACKGROUND

Surgical resection of oligometastatic disease has been shown to be associated with an improved survival in other malignancies, though its role is not established in metastatic urothelial carcinoma (mUC). We sought to examine utilization trends of metastasectomy in mUC and associated outcomes using the NCDB database.

METHODS

We queried the NCDB from 2004 to 2016 for patients with metastatic urothelial carcinoma who had undergone metastasectomy. The annual utilization trend of metastasectomy was evaluated by linear regression. We compared overall survival (OS) between propensity score matched patients who had undergone metastasectomy and those who had not using two-sided log-rank and Cox regression models. We also performed sensitivity analyses on subcohorts of mUC.

RESULTS

The utilization rate of metastasectomy in mUC was 7% and did not change significantly over time. Patients who received metastasectomy on average were younger, had >cT3 disease, had radical surgery to the primary tumor, and received systemic therapy. After propensity score matching, metastasectomy was not associated with an OS benefit for mUC patients (HR, 0.94; 95% CI, 0.83 to 1.07; P=0.38). Stratified subgroup analysis based on systemic therapy, radical surgery to primary tumor, clinical N stage, and primary location of disease did not show an OS benefit of metastasectomy.

CONCLUSION

Metastasectomy is uncommonly used, though utilization has persisted over more than a decade. Despite selection biases and residual confounding favoring patients undergoing metastasectomy, we found similar OS among these individuals and those who did not undergo metastasectomy.

Assessing Impact of Household Intervention on Indoor Air Quality and Health of Children with Asthma in the US-Mexico Border: A Pilot Study

Few studies have investigated household interventions to enhance indoor air quality (IAQ) and health outcomes in relatively low-income communities. This study aims to examine the impact of the combined intervention with asthma education and air purifier on IAQ and health outcomes in the US-Mexico border area. An intervention study conducted in McAllen, Texas, between June and November 2019 included 16 households having children with asthma. The particulate matter (PM2.5) levels were monitored in the bedroom, kitchen, and living room to measure the IAQ for 7 days before and after the intervention, respectively. Multiple surveys were applied to evaluate changes in children's health outcomes. The mean PM2.5 levels in each place were significantly improved. Overall, they significantly decreased by 1.91 μg/m3 on average (p < 0.05). All surveys showed better health outcomes; particularly, quality of life for children was significantly improved (p < 0.05). This pilot study suggests that the combined household intervention might improve IAQ in households and health outcomes for children with asthma and reduce health disparities in low-income communities. Future large-scale studies are needed to verify the effectiveness of this household intervention to improve IAQ and asthma management.

Prospective cohort study of respiratory effects at ages 14 to 26 following early life exposure to arsenic in drinking water

BACKGROUND

We previously reported chronic respiratory effects in children who were then 7-17 years of age in Matlab, Bangladesh. One group of children had been exposed to high concentrations of arsenic in drinking water in utero and early childhood (average 436 µg/L), and the other group of children were never known to have been exposed to >10 µg/L. The exposed children, both males and females, had marked increases in chronic respiratory symptoms.

METHODS

The current study involves a further follow-up of these children now 14-26 years of age with 463 located and agreeing to participate. They were interviewed for respiratory symptoms and lung function was measured. Data were collected on smoking, body mass index (BMI), and number of rooms in the house as a measure of socioeconomic status.

RESULTS

Respiratory effects were still present in males but not females. In the high exposure group (>400 µg/L in early life) the odds ratio (OR) among male participants for dry cough in the last 12 months was 2.36 (95% confidence interval [CI] = 1.21, 4.63, P = 0.006) and for asthma OR = 2.51 (95% CI = 1.19, 5.29, P = 0.008). Forced vital capacity (FVC) was reduced in males in the early life high-exposure group compared with those never exposed (-95ml, P = 0.04), but not in female participants.

CONCLUSIONS

By the age range 14-26, there was little remaining evidence of chronic respiratory effects in females but pronounced effects persisted in males. Mechanisms for the marked male female differences warrant further investigation along with further follow-up to see if respiratory effects continue in males.

Socioeconomic status and the association between arsenic exposure and type 2 diabetes

OBJECTIVE

Evaluate whether arsenic-related diabetes risks differ between people of low and high socioeconomic status (SES).

METHODS

We used data collected between October 2007-December 2010 from a population-based cancer case-control study (N = 1301) in Northern Chile, an area with high arsenic water concentrations (>800 µg/L) and comprehensive records of past exposure. Information on lifetime exposure and potential confounders were obtained using structured interviews, questionnaires, and residential histories. Type 2 diabetes was defined as physician-diagnosed diabetes or oral hypoglycemic medication use. SES was measured using a 14-point scale based on ownership of household appliances, cars, internet access, or use of domestic help. Logistic regression was used to assess the relationship between arsenic and diabetes within strata of SES.

RESULTS

Among those with low SES, the odds ratio (OR) for diabetes comparing individuals in the highest to lowest tertile of lifetime average arsenic exposure was 2.12 (95% confidence interval (CI) 1.29-3.49, p = 0.004). However, those in the high SES group were not at increased risk (OR = 1.12 [95% CI = 0.72-1.73]).

CONCLUSIONS

Our findings provide evidence that risks of arsenic-related diabetes may be higher in Chile in people with low versus high SES.

Risk assessment of endocrine disrupting phthalates and hormonal alterations in children and adolescents

Risk assessment and hormone evaluation were carried out for di(2-ethylhexyl) phthalate (DEHP) and dibutyl phthalate (DBP), endocrine disrupting chemicals (EDCs), in 302 Korean children (n = 223) and adolescents (n = 79) (< age 19). Urinary and serum concentrations of DEHP, MEHP (mono(2-ethylhexyl) phthalate), DBP, MBP (monobutyl phthalate), and PA (phthalic acid, a common final metabolite of phthalates) were detected in children and adolescents. Daily exposure levels were estimated to be 16.45 ± 36.50 μg/kg b.w./day for DEHP, which is one-third of the tolerable daily intake (TDI) value (50 μg/kg b.w./day), but 14 out of 302 participants had a hazard index (HI = intake/TDI) value >1. The mean daily exposure level of DBP was 1.23 ± 1.45 μg/kg b.w./day, which is one-eighth of the TDI value (10 μg/kg b.w./day), but 1 out of 302 participants had a HI value > 1. Positive correlations were observed between serum DBP or MEHP, and serum estradiol (E2) and/or luteinizing hormone (LH) in prepubescent children. In addition, serum MBP levels were found to be negatively correlated with serum triiodothyronine (T3) or thyroxine (T4) in male participants, and serum DEHP levels with serum thyroid stimulating hormone (TSH) in female adolescents. Low-density lipoprotein (LDL) levels were positively correlated with serum PA levels in children and adolescents. DEHP, DBP or its metabolites may be associated with altered hormone levels in children and adolescents. Data suggest that exposure levels of DEHP and DBP in Korean children need to be reduced to levels below TDI to protect them from EDC-mediated toxicities. Abbreviations: DBP: dibutyl phthalate; DEHP: di(2-ethylhexyl) phthalate; E2: estradiol; EDC: endocrine disrupting chemical; EFSA: European Food Safety Authority; FSH: follicle stimulating hormone; HDL: high density lipoprotein; HI: hazard index; LDL: low density lipoprotein; LH: luteinizing hormone; MEHP: mono(2-ethylhexyl) phthalate; MBP: monobutyl phthalate; PA: phthalic acid; PPAR: peroxisome proliferator-activated receptor gamma; PVC: polyvinyl chloride; T3: triiodothyronine; T4: thyroxine; TDI: tolerable daily intake; TG: triglyceride; TSH: thyroid stimulating hormone; UPLC/MS/MS: Ultra Performance Liquid Chromatography/Tandem Mass Spectrometry; WWF: World Wildlife Fund.

Age at Exposure to Arsenic in Water and Mortality 30-40 Years After Exposure Cessation

Arsenic in drinking water is known to cause cancer and noncancer diseases, but little is known about its association with age at exposure. Here, we investigated age at arsenic exposure and mortality in Antofagasta, Chile, 30-40 years after a distinct period of very high water arsenic concentrations (1958-1970). We calculated standardized mortality ratios (SMRs) comparing Antofagasta with the rest of Chile for 2001-2010 by sex and age at potential first exposure. A remarkable relationship with age at first exposure was found for bronchiectasis, with increased risk in adults 30-40 years after exposure being confined to those who were in utero (SMR = 11.7, 95% confidence interval (CI): 4.3, 25.4) or aged 1-10 years (SMR = 5.4, 95% CI: 1.1, 15.8) during the high-exposure period. Increased SMRs for lung, bladder, and laryngeal cancer were evident for exposures starting at all ages, but the highest SMRs were for exposures beginning at birth (for bladder cancer, SMR = 16.0 (95% CI: 10.3, 23.8); for laryngeal cancer, SMR = 6.8 (95% CI: 2.2, 15.8); for lung cancer, SMR = 3.8 (95% CI: 2.9, 4.9)). These findings suggest that interventions targeting early-life arsenic exposure could have major impacts in reducing long-term mortality due to arsenic 30-40 years after exposure ends.

Lung, Bladder, and Kidney Cancer Mortality 40 Years After Arsenic Exposure Reduction

Background

Region II in northern Chile (population 442 570) experienced a sudden major increase in arsenic water concentrations in 1958 in the main city of Antofagasta, followed by a major reduction in exposure when an arsenic removal plant was installed in 1970. It provides a unique opportunity to study latency effects of exposure to arsenic, and this is the first study with mortality data up to 40 years after exposure reduction.

Methods

We previously identified high mortality rates in Region II up to the year 2000. Here we present rate ratios (RRs) for Region II compared with all the rest of Chile from 2001 to 2010, and with unexposed Region V (population 1 539 852) for all years from 1950 to 2010. All statistical tests were one-sided.

Results

From 2001 to 2010, comparing Region II with the rest of Chile, lung and bladder mortality were still greatly elevated (RR = 3.38, 95% confidence interval [CI] = 3.19 to 3.58, P < .001 for lung cancer in men; RR = 2.41, 95% CI = 2.20 to 2.64, P < .001 for lung cancer in women; RR = 4.79, 95% CI = 4.20 to 5.46, P < .001 for bladder cancer in men; RR = 6.43, 95% CI = 5.49 to 7.54, P < .001 for bladder cancer in women). Kidney cancer mortality was also elevated (RR = 1.75, 95% CI = 1.49 to 2.05, P < .001 for men; RR = 2.09, 95% CI = 1.69 to 2.57, P < .001 for women). Earlier short latency acute myocardial infarction mortality increases had subsided.

Conclusions

Lung, bladder, and kidney cancer mortality due to arsenic exposure have very long latencies, with increased risks manifesting 40 years after exposure reduction. Our findings suggest that arsenic in drinking water may involve one of the longest cancer latencies for a human carcinogen.

Low-level arsenic exposure from drinking water is associated with prostate cancer in Iowa

Inorganic arsenic is a toxic naturally occurring element in soil and water in many regions of the US including the Midwest. Prostate cancer is the second most common type of cancer in men in Iowa, surpassed only by non-melanotic skin cancer. Epidemiology studies have evaluated arsenic exposure from drinking water and prostate cancer, but most have focused on high-level exposures outside the US. As drinking water from groundwater sources is a major source of arsenic exposure, we conducted an ecologic study to evaluate prostate cancer and arsenic in drinking water from public water sources and private wells in Iowa, where exposure levels are low, but duration of exposure can be long. Arsenic data from public water systems were obtained from the Iowa Safe Drinking Water Information System for the years 1994-2003 and for private wells from two Iowa Well Water Studies, the Iowa Community Private Well Study (ICPWS, 2002-2003) and Iowa Statewide Rural Well Water Survey Phase 2 (SWIRL2, 2006-2008) that provided data for 87 Iowa counties. Prostate cancer incidence data from 2009 to 2013 for Iowa were obtained from Surveillance, Epidemiology and End Results' SEER*Stat software. County averages of water arsenic levels varied from 1.08 to 18.6 ppb, with three counties above the current 10 ppb limit. Based on the tertiles of arsenic levels, counties were divided into three groups: low (1.08-2.06 ppb), medium (2.07-2.98 ppb), and high (2.99-18.6 ppb). Spatial Poisson regression modeling was conducted to estimate the risk ratios (RR) of prostate cancer by tertiles of arsenic level at a county level, adjusted for demographic and risk factors. The RR of prostate cancer were 1.23 (95% CI, 1.16-1.30) and 1.28 (95% CI, 1.21-1.35) in the medium and high groups, respectively, compared to the low group after adjusting for risk factors. The RR increased to 1.36 (95% CI, 1.28-1.45) in the high group when analyses were restricted to aggressive prostate cancers (Gleason score ≥ 7). This study shows a significant dose-dependent association between low-level arsenic exposure and prostate cancer, and if this result is replicated in future individual-level studies, may suggest that 10 ppb is not protective for human health.

The no-observed-adverse-effect level (NOAEL) of baby aloe powder (BAP) for nutraceutical application based upon toxicological evaluation

Aloe has been used in versatile herbal medications and nutraceuticals throughout history. Aloe is widely considered to be generally safe for humans and used globally. The effectiveness and pharmacological properties of aloe are dependent upon when the plant is collected. However, little is known about the toxicology of whole-body aloe collected within less than 1 yr. Based upon widespread exposure to aloe, it is important to determine a daily intake level of this chemical to ensure its safety for humans. To determine the no-observed-adverse-effect level (NOAEL) of baby aloe powder (BAP) for clinical application, Sprague-Dawley (SD) rats were treated orally for 4 wk with 4 different concentrations: 0, 0.125, 0.5, and 2 g/kg body weight (bw). In this study, no significant or dose-dependent toxicological effects of BAP were observed in biochemical or hematological parameters, urinalysis, clinical signs, body weight, and food and water consumption. There were changes in some biomarkers in certain treated groups compared to controls; however, all values were within their reference ranges and not dose-dependent. Based on these results, the NOAEL of BAP was estimated to be greater than 2 g/kg bw in male and 2 g/kg bw in female SD rats. Collectively, these data suggest that BAP used in this study did not produce any marked subacute toxic effects up to a maximum concentration of 2 g/kg bw, and thus use in nutraceuticals and in pharmaceutical and cosmetic applications at a concentration of >2 g/kg is warranted.

Comparative nephrotoxicitiy induced by melamine, cyanuric acid, or a mixture of both chemicals in either Sprague-Dawley rats or renal cell lines

Acute nephrotoxicities of melamine (MEL), cyanuric acid (CA), and a mixture of both melamine and cyanuric acid (MC) were comparatively investigated in male Sprague-Dawley rats at 5 doses each with 10-fold dose interval as follows: MEL at 0.0315, 0.315, 3.15, 31.5, and 315 mg/kg; CA at 0.025, 0.25, 2.5, 25, and 250 mg/kg, and MC: [1×: (0.0315 + 0.025), 10×: (0.315 + 0.25), 100×: (3.15 + 2.5), 1000×: (31.5 + 25), and (315 + 250) mg/kg]. No marked adverse effects in renal function were observed in animals treated with MEL alone or CA alone, but evidence related to nephrotoxicity was noted in rats administered MC. Renal calculi and increased kidney weights were found in rats 7 d after daily oral administration of MC. Blood urea nitrogen (BUN) and creatinine were significantly elevated in the high dose MC groups at 100× or 1000×. In addition, elevated numbers of white blood cells (WBC), neutrophils, and lymphocytes in vivo and increased levels of prostaglandin E(2) (PGE(2)) in vitro were found in the MC group. Based on these data, the NOAEL (no-observed-adverse-effect level) for nephrotoxicity for MC was estimated to be 3.15 mg/kg body weight (bw)/d (MEL) plus 2.5 mg/kg bw/d (CA). If a safety factor of 1000 or more were applied to NOAEL, tolerable daily intake (TDI) would be 0.00315 and 0.0025 mg/kg/d or less for MEL and CA, respectively, which is far below the TDI of 0.2 mg/kg/d set by World Health Organization (WHO). In addition, in vitro cytotoxicity assays showed that the ACHN human renal adenocarcinoma cell line was more sensitive to MEL, CA, and MC than the MDCK canine kidney epithelial cell line. The 24-h half maximal inhibitory concentration (IC(50)) values for MEL (4792, 2792 μg/ml) were less than those of CA (9890, 6725 μg/ml, respectively) in MDCK and ACHN cell lines, suggesting that MEL may be more cytotoxic than CA. Furthermore, the 24-h IC(50) value for MC was found to be 208 μg/ml in ACHN cells. Data suggest that NOAELs based upon acute nephrotoxic parameters for MC were low, which might require further reassessment of the current TDI.

Investigation of sulfhydryl groups in cabbage phospholipase D by combination of derivatization methods and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry

All eight cysteine residues in 92 kDa cabbage phospholipase D (PLD), deduced from the cDNA sequence, were shown to have free sulfhydryl groups by analysis using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOFMS) of tryptic peptides of PLD derivatized with p-chloromercurybenzoate, iodoacetic acid, and N-ethylmaleimide, as well as of underivatized PLD. Assignment of sulfhydryl groups by any one method was not conclusive. However, complementary information derived from tryptic peptides derivatized with different reagents made full assignment of sulfhydryl groups possible.

Button-down procedure for correction of cleft earlobe malformation

The button-down procedure for correction of a tag and cleft type of cleft earlobe malformation has been presented. The method is simple and easy to perform. We were able to add relative fullness with a natural look to several malformed earlobes that satisfactorily matched the contralateral earlobe in size and shape. The patients and their parents were pleased with our results.

[Total liver failure in the scintigram of alcoholic liver cirrhosis]

Case reports are given of 3 female patients suffering from advanced, hypertrophic alcoholic cirrhosis of the liver with portal hypertension. The livers of these patients were not demonstrable by scintigraphy. The patients died a few months afterwards from liver failure. This syndrome - failure of the liver to show up in scintigraphy - may have diagnostic and prognostic implications; it may be caused by deficient blood circulation and by reduced phagocytic capacity of the kupfer cell system.