Veteran teacher Katherine A. James responds to a March 2022 Kappan article in which high school student Colin McGrath warned his younger brother of the burden that pointless homework assignments will ...play in his life when he enters high school. James suggests that, although some teachers may assign work with little value, most assignments do serve to either reinforce or expand on what students have learned in class. She urges teachers and students to think of homework as opportunities for learning at home. Ideally, teachers will explain the purpose of any at-home learning and give students options for engaging in such learning, using their individual intelligences to master the content.
Consistent evidence at high levels of water arsenic (≥100 µg/l), and growing evidence at low-moderate levels (<100 µg/l), support a link with cardiovascular disease (CVD). The shape of the ...dose-response across low-moderate and high levels of arsenic in drinking water is uncertain and critical for risk assessment.
We conducted a systematic review of general population epidemiological studies of arsenic and incident clinical CVD (all CVD, coronary heart disease (CHD) and stroke) with three or more exposure categories. In a dose-response meta-analysis, we estimated the pooled association between log-transformed water arsenic (log-linear) and restricted cubic splines of log-transformed water arsenic (non-linear) and the relative risk of each CVD endpoint.
Twelve studies (pooled N = 408 945) conducted at high (N = 7) and low-moderate (N = 5) levels of water arsenic met inclusion criteria, and 11 studies were included in the meta-analysis. Compared with 10 µg/l, the estimated pooled relative risks 95% confidence interval (CI) for 20 µg/l water arsenic, based on a log-linear model, were 1.09 (1.03, 1.14) (N = 2) for CVD incidence, 1.07 (1.01, 1.14) (N = 6) for CVD mortality, 1.11 (1.05, 1.17) (N = 4) for CHD incidence, 1.16 (1.07, 1.26) (N = 6) for CHD mortality, 1.08 (0.99, 1.17) (N = 2) for stroke incidence and 1.06 (0.93, 1.20) (N = 6) for stroke mortality. We found no evidence of non-linearity, although these tests had low statistical power.
Although limited by the small number of studies, this analysis supports quantitatively including CVD in inorganic arsenic risk assessment, and strengthens the evidence for an association between arsenic and CVD across low-moderate to high levels.
To estimate prevalence of childhood-onset Duchenne and Becker muscular dystrophies (DBMD) in 6 sites in the United States by race/ethnicity and phenotype (Duchenne muscular dystrophy DMD or Becker ...muscular dystrophy BMD).
In 2002, the Centers for Disease Control and Prevention established the Muscular Dystrophy Surveillance, Tracking, and Research Network (MD STARnet) to conduct longitudinal, population-based surveillance and research of DBMD in the United States. Six sites conducted active, multiple-source case finding and record abstraction to identify MD STARnet cases born January 1982 to December 2011. We used cross-sectional analyses to estimate prevalence of DBMD per 10 000 boys, ages 5 to 9 years, for 4 quinquennia (1991-1995, 1996-2000, 2001-2005, and 2006-2010) and prevalence per 10 000 male individuals, ages 5 to 24 years, in 2010. Prevalence was also estimated by race/ethnicity and phenotype.
Overall, 649 cases resided in an MD STARnet site during ≥1 quinquennia. Prevalence estimates per 10 000 boys, ages 5 to 9 years, were 1.93, 2.05, 2.04, and 1.51, respectively, for 1991-1995, 1996-2000, 2001-2005, and 2006-2010. Prevalence tended to be higher for Hispanic individuals than non-Hispanic white or black individuals, and higher for DMD than BMD. In 2010, prevalence of DBMD was 1.38 per 10 000 male individuals, ages 5 to 24 years.
We present population-based prevalence estimates for DBMD in 6 US sites. Prevalence differed by race/ethnicity, suggesting potential cultural and socioeconomic influences in the diagnosis of DBMD. Prevalence also was higher for DMD than BMD. Continued longitudinal surveillance will permit us to examine racial/ethnic and socioeconomic differences in treatment and outcomes for MD STARnet cases.
•Case-cohort study included a randomly selected subcohort and 809 AMI cases.•Participants had relatively low urinary cadmium compared to prior studies.•We found little evidence that cadmium at ...relatively low-levels is associated with AMI.•Results were not materially different across strata defined by sex.•Similar results using creatinine or osmolality to account for urine dilution.
Cadmium exposure has been associated with cardiovascular disease. Cigarette smoking is a key source of cadmium exposure and thus a potential confounder in observational studies of environmental cadmium and cardiovascular disease that include tobacco smokers. We leveraged up to 20 years of follow-up in the Danish Diet, Cancer and Health cohort to test the hypothesis that cadmium exposure is associated with acute myocardial infarction (AMI) among people who never smoked. Between 1993 and 1997, 19,394 never-smoking participants (ages 50–64 years) were enrolled and provided a urine sample. From this sample, we randomly selected a subcohort of 600 males and 600 females. We identified 809 AMI cases occurring between baseline and the end of 2015 using the Danish National Patient Registry. We quantified cadmium, creatinine, and osmolality in baseline urine samples. Using an unweighted case-cohort approach, we estimated adjusted hazard ratios (aHR) for AMI in Cox proportional hazards models with age as the time axis. Participants had relatively low concentrations of urinary cadmium, as expected for never smokers (median = 0.20; 25th, 75th = 0.13, 0.32 μg cadmium/g creatinine). We did not find strong evidence to support an association between higher urinary cadmium and AMI when comparing the highest versus lowest quartile (aHR = 1.16; 95% CI: 0.86 – 1.56) and per IQR increment in cadmium concentration (aHR = 1.02; 95% CI: 0.93 – 1.12). Results were not materially different across strata defined by sex. Results were generally similar using creatinine or osmolality to account for differences in urine dilution. While cadmium exposure has been identified as a risk factor for cardiovascular disease, we did not find strong evidence that urinary cadmium at relatively low-levels is associated with AMI among people who have never smoked.
Environmental causes of cardiovascular diseases (CVDs) are global health issues. In particular, an association between metal exposure and CVDs has become evident but causal evidence still lacks. ...Therefore, this symposium at the Society of Toxicology 2022 annual meeting addressed epidemiological, clinical, pre-clinical animal model-derived and mechanism-based evidence by five presentations: 1) An epidemiologic study on potential CVD risks of individuals exposed occupationally and environmentally to heavy metals; 2) Both presentations of the second and third were clinical studies focusing on the potential link between heavy metals and pulmonary arterial hypertension (PAH), by presenting altered blood metal concentrations of both non-essential and essential metals in the patients with PAH and potential therapeutic approaches; 3) Arsenic-induced atherosclerosis via inflammatory cells in mouse model; 4) Pathogenic effects on the heart by adult chronic exposure to very low-dose cadmium via epigenetic mechanisms and whole life exposure to low dose cadmium via exacerbating high-fat-diet-lipotoxicity. This symposium has brought epidemiologists, therapeutic industry, physicians, and translational scientists together to discuss the health risks of occupational and environmental exposure to heavy metals through direct cardiotoxicity and indirect disruption of homeostatic mechanisms regulating essential metals, as well as lipid levels. The data summarized by the presenters infers a potential causal link between multiple metals and CVDs and defines differences and commonalities. Therefore, summary of these presentations may accelerate the development of efficient preventive and therapeutic strategies by facilitating collaborations among multidisciplinary investigators.
•CVD trends with environmental metal contamination continues increase globally•Potential link of non-essential metals to pulmonary arterial hypertension as one of CVDs•Three main clusters of macrophages independently involve in As-induced atherosclerosis•Exposure to low-dose cadmium may not directly induce, but increase HFD cardiotoxicity
Limited evidence suggests that antimony induces vascular inflammation and oxidative stress and may play a role in cardiovascular disease (CVD) risk. However, few studies have examined whether ...environmental antimony from sources other than tobacco smoking is related with CVD risk. The general population may be exposed through air, drinking water, and food that contains antimony from natural and anthropogenic sources, such as mining, coal combustion, and manufacturing.
To examine the association of urine antimony with incident acute myocardial infarction (AMI), heart failure, and stroke among people who never smoked tobacco.
Between 1993 and 1997, the Danish Diet, Cancer and Health (DCH) cohort enrolled participants (ages 50–64 years), including n = 19,394 participants who reported never smoking at baseline. Among these never smokers, we identified incident cases of AMI (N = 809), heart failure (N = 958), and stroke (N = 534) using the Danish National Patient Registry. We also randomly selected a subcohort of 600 men and 600 women. We quantified urine antimony concentrations in samples provided at enrollment. We used modified Cox proportional hazards models to estimate adjusted hazard ratios (HR) for each incident CVD outcome in relation to urine antimony, statistically adjusted for creatinine. We used a separate prospective cohort, the San Luis Valley Diabetes Study (SLVDS), to replicate these results.
In the DCH cohort, urine antimony concentrations were positively associated with rates of AMI and heart failure (HR = 1.52; 95%CI = 1.12, 2.08 and HR = 1.58; 95% CI = 1.15, 2.18, respectively, comparing participants in the highest (>0.09 µg/L) with the lowest quartile (<0.02 µg/L) of antimony). In the SLVDS cohort, urinary antimony was positively associated with AMI, but not heart failure.
Among this sample of Danish people who never smoked, we found that low levels of urine antimony are associated with incident CVD. These results were partially confirmed in a smaller US cohort.
Chronic diseases, including coronary heart disease (CHD), have been associated with ingestion of drinking water with high levels of inorganic arsenic (> 1,000 μg/L). However, associations have been ...inconclusive in populations with lower levels (< 100 μg/L) of inorganic arsenic exposure.
We conducted a case-cohort study based on individual estimates of lifetime arsenic exposure to examine the relationship between chronic low-level arsenic exposure and risk of CHD.
This study included 555 participants with 96 CHD events diagnosed between 1984 and 1998 for which individual lifetime arsenic exposure estimates were determined using data from structured interviews and secondary data sources to determine lifetime residence, which was linked to a geospatial model of arsenic concentrations in drinking water. These lifetime arsenic exposure estimates were correlated with historically collected urinary arsenic concentrations. A Cox proportional-hazards model with time-dependent CHD risk factors was used to assess the association between time-weighted average (TWA) lifetime exposure to low-level inorganic arsenic in drinking water and incident CHD.
We estimated a positive association between low-level inorganic arsenic exposure and CHD risk hazard ratio (HR): = 1.38, 95% CI: 1.09, 1.78 per 15 μg/L while adjusting for age, sex, first-degree family history of CHD, and serum low-density lipoprotein levels. The risk of CHD increased monotonically with increasing TWAs for inorganic arsenic exposure in water relative to < 20 μg/L (HR = 1.2, 95% CI: 0.6, 2.2 for 20-30 μg/L; HR = 2.2; 95% CI: 1.2, 4.0 for 30-45 μg/L; and HR = 3, 95% CI: 1.1, 9.1 for 45-88 μg/L).
Lifetime exposure to low-level inorganic arsenic in drinking water was associated with increased risk for CHD in this population.
Although the presence of intermediate snails is a necessary condition for local schistosomiasis transmission to occur, using them as surveillance targets in areas approaching elimination is ...challenging because the patchy and dynamic quality of snail host habitats makes collecting and testing snails labor-intensive. Meanwhile, geospatial analyses that rely on remotely sensed data are becoming popular tools for identifying environmental conditions that contribute to pathogen emergence and persistence.
In this study, we assessed whether open-source environmental data can be used to predict the presence of human Schistosoma japonicum infections among households with a similar or improved degree of accuracy compared to prediction models developed using data from comprehensive snail surveys. To do this, we used infection data collected from rural communities in Southwestern China in 2016 to develop and compare the predictive performance of two Random Forest machine learning models: one built using snail survey data, and one using open-source environmental data.
The environmental data models outperformed the snail data models in predicting household S. japonicum infection with an estimated accuracy and Cohen's kappa value of 0.89 and 0.49, respectively, in the environmental model, compared to an accuracy and kappa of 0.86 and 0.37 for the snail model. The Normalized Difference in Water Index (an indicator of surface water presence) within half to one kilometer of the home and the distance from the home to the nearest road were among the top performing predictors in our final model. Homes were more likely to have infected residents if they were further from roads, or nearer to waterways.
Our results suggest that in low-transmission environments, leveraging open-source environmental data can yield more accurate identification of pockets of human infection than using snail surveys. Furthermore, the variable importance measures from our models point to aspects of the local environment that may indicate increased risk of schistosomiasis. For example, households were more likely to have infected residents if they were further from roads or were surrounded by more surface water, highlighting areas to target in future surveillance and control efforts.
Physicians' views about health care costs are germane to pending policy reforms.
To assess physicians' attitudes toward and perceived role in addressing health care costs.
A cross-sectional survey ...mailed in 2012 to 3897 US physicians randomly selected from the AMA Masterfile.
Enthusiasm for 17 cost-containment strategies and agreement with an 11-measure cost-consciousness scale.
A total of 2556 physicians responded (response rate = 65%). Most believed that trial lawyers (60%), health insurance companies (59%), hospitals and health systems (56%), pharmaceutical and device manufacturers (56%), and patients (52%) have a "major responsibility" for reducing health care costs, whereas only 36% reported that practicing physicians have "major responsibility." Most were "very enthusiastic" for "promoting continuity of care" (75%), "expanding access to quality and safety data" (51%), and "limiting access to expensive treatments with little net benefit" (51%) as a means of reducing health care costs. Few expressed enthusiasm for "eliminating fee-for-service payment models" (7%). Most physicians reported being "aware of the costs of the tests/treatments they recommend" (76%), agreed they should adhere to clinical guidelines that discourage the use of marginally beneficial care (79%), and agreed that they "should be solely devoted to individual patients' best interests, even if that is expensive" (78%) and that "doctors need to take a more prominent role in limiting use of unnecessary tests" (89%). Most (85%) disagreed that they "should sometimes deny beneficial but costly services to certain patients because resources should go to other patients that need them more." In multivariable logistic regression models testing associations with enthusiasm for key cost-containment strategies, having a salary plus bonus or salary-only compensation type was independently associated with enthusiasm for "eliminating fee for service" (salary plus bonus: odds ratio OR, 3.3, 99% CI, 1.8-6.1; salary only: OR, 4.3, 99% CI, 2.2-8.5). In multivariable linear regression models, group or government practice setting (β = 0.87, 95% CI, 0.29 to 1.45, P = .004; and β = 0.99, 95% CI, 0.20 to 1.79, P = .01, respectively) and having a salary plus bonus compensation type (β = 0.82; 95% CI, 0.32 to 1.33; P = .002) were positively associated with cost-consciousness. Finding the "uncertainty involved in patient care disconcerting" was negatively associated with cost-consciousness (β = -1.95; 95% CI, -2.71 to -1.18; P < .001).
In this survey about health care cost containment, US physicians reported having some responsibility to address health care costs in their practice and expressed general agreement about several quality initiatives to reduce cost but reported less enthusiasm for cost containment involving changes in payment models.
Reference genome and transcriptome assemblies of helminths have reached a level of completion whereby secondary analyses that rely on accurate gene estimation or syntenic relationships can be now ...conducted with a high level of confidence. Recent public release of the v.3 assembly of the mouse bile-duct tapeworm, Hymenolepis microstoma, provides chromosome-level characterisation of the genome and a stabilised set of protein coding gene models underpinned by bioinformatic and empirical data. However, interactome data have not been produced. Conserved protein-protein interactions in other organisms, termed interologs, can be used to transfer interactions between species, allowing systems-level analysis in non-model organisms.
Here, we describe a probabilistic, integrated network of interologs for the H. microstoma proteome, based on conserved protein interactions found in eukaryote model species. Almost a third of the 10,139 gene models in the v.3 assembly could be assigned interaction data and assessment of the resulting network indicates that topologically-important proteins are related to essential cellular pathways, and that the network clusters into biologically meaningful components. Moreover, network parameters are similar to those of single-species interaction networks that we constructed in the same way for S. cerevisiae, C. elegans and H. sapiens, demonstrating that information-rich, system-level analyses can be conducted even on species separated by a large phylogenetic distance from the major model organisms from which most protein interaction evidence is based. Using the interolog network, we then focused on sub-networks of interactions assigned to discrete suites of genes of interest, including signalling components and transcription factors, germline multipotency genes, and genes differentially-expressed between larval and adult worms. Results show not only an expected bias toward highly-conserved proteins, such as components of intracellular signal transduction, but in some cases predicted interactions with transcription factors that aid in identifying their target genes.
With key helminth genomes now complete, systems-level analyses can provide an important predictive framework to guide basic and applied research on helminths and will become increasingly informative as new protein-protein interaction data accumulate.
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