Epidemiologic Studies in Human Populations

Abstract BACKGROUND Perfluoroalkyl and polyfluoroalkyl substances (PFAS) are found widespread in drinking water, foods, food packaging materials and other consumer products. Several PFAS have been identified as endocrine-disrupting chemicals based on their ability to interfere with normal reproductive function and hormonal signalling. Experimental models and epidemiologic studies suggest that PFAS exposures target the ovary and represent major risks for women’s health. OBJECTIVE AND RATIONALE This review summarises human population and toxicological studies on the association between PFAS exposure and ovarian function. SEARCH METHODS A comprehensive review was performed by searching PubMed. Search terms included an extensive list of PFAS and health terms ranging from general keywords (e.g. ovarian, reproductive, follicle, oocyte) to specific keywords (including menarche, menstrual cycle, menopause, primary ovarian insufficiency/premature ovarian failure, steroid hormones), based on the authors’ knowledge of the topic and key terms. OUTCOMES Clinical evidence demonstrates the presence of PFAS in follicular fluid and their ability to pass through the blood–follicle barrier. Although some studies found no evidence associating PFAS exposure with disruption in ovarian function, numerous epidemiologic studies, mostly with cross-sectional study designs, have identified associations of higher PFAS exposure with later menarche, irregular menstrual cycles, longer cycle length, earlier age of menopause and reduced levels of oestrogens and androgens. Adverse effects of PFAS on ovarian folliculogenesis and steroidogenesis have been confirmed in experimental models. Based on laboratory research findings, PFAS could diminish ovarian reserve and reduce endogenous hormone synthesis through activating peroxisome proliferator-activated receptors, disrupting gap junction intercellular communication between oocyte and granulosa cells, inducing thyroid hormone deficiency, antagonising ovarian enzyme activities involved in ovarian steroidogenesis or inhibiting kisspeptin signalling in the hypothalamus. WIDER IMPLICATIONS The published literature supports associations between PFAS exposure and adverse reproductive outcomes; however, the evidence remains insufficient to infer a causal relationship between PFAS exposure and ovarian disorders. Thus, more research is warranted. PFAS are of significant concern because these chemicals are ubiquitous and persistent in the environment and in humans. Moreover, susceptible groups, such as foetuses and pregnant women, may be exposed to harmful combinations of chemicals that include PFAS. However, the role environmental exposures play in reproductive disorders has received little attention by the medical community. To better understand the potential risk of PFAS on human ovarian function, additional experimental studies using PFAS doses equivalent to the exposure levels found in the general human population and mixtures of compounds are required. Prospective investigations in human populations are also warranted to ensure the temporality of PFAS exposure and health endpoints and to minimise the possibility of reverse causality.

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Inorganic arsenic and human prostate cancer

Ciência & Saúde Coletiva ◽

10.1590/s1413-81232009000100037 ◽

2009 ◽

Vol 14 (1) ◽

pp. 307-318 ◽

Cited By ~ 2

Author(s):

Lamia Benbrahim-Tallaa ◽

Michael Waalkes

Keyword(s):

Prostate Cancer ◽

Animal Studies ◽

Arsenic Exposure ◽

Inorganic Arsenic ◽

Epidemiologic Studies ◽

Model Systems ◽

Human Prostate ◽

Human Populations ◽

Human Prostate Cancer

We critically evaluated the etiologic role of inorganic arsenic in human prostate cancer. We assessed data from relevant epidemiologic studies concerning environmental inorganic arsenic exposure. Whole animal studies were evaluated as were in vitro model systems of inorganic arsenic carcinogenesis in the prostate. Multiple studies in humans reveal an association between environmental inorganic arsenic exposure and prostate cancer mortality or incidence. Many of these human studies provide clear evidence of a dose-response relationship. Relevant whole animal models showing a relationship between inorganic arsenic and prostate cancer are not available. However, cellular model systems indicate arsenic can induce malignant transformation of human prostate epithelial cells in vitro. Arsenic also appears to impact prostate cancer cell progression by precipitating events leading to androgen independence in vitro. Available evidence in human populations and human cells in vitro indicates that the prostate is a target for inorganic arsenic carcinogenesis. A role for this common environmental contaminant in human prostate cancer initiation and/or progression would be very important.

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Stages in Cancer Development: Opportunities for Thresholds

Journal of the American College of Toxicology ◽

10.3109/10915818309140707 ◽

1983 ◽

Vol 2 (3) ◽

pp. 269-283

Author(s):

Paul M. Newberne

Keyword(s):

Animal Models ◽

Lag Time ◽

Epidemiologic Studies ◽

Cancer Development ◽

Human Populations ◽

Time Varying ◽

Factors Associated ◽

Number Of Factors ◽

Cellular Alterations

It has now been established that many factors can influence the development of cancer in animal models. Epidemiologic studies support the concept of a similar situation in human populations with particular emphasis on lifestyle. Types of cancer which appear to be excellent candidates for such influences are colon, breast and lung. In the case of each there are antecedent (pre-neoplastic) changes in morphology of focal areas in the organ or tissue and a lag time varying from a few years to decades. It seems logical that thresholds do exist in some such cases and that if a threshold is not exceeded for whatever substance or condition may be primary to the cardnogenesis process, the atypical cellular alterations may regress or at most remain static. Furthermore, factors associated with lifestyle, including diet, can likely determine whether or not the progress toward malignancy is initiated, inhibited, or enhanced in a given organ or tissue. A number of factors or conditions which may relate to inhibiting or enhancing cardnogenesis are considered in this presentation. Mechanisms for such effects may be mediated by raising or lowering thresholds. This area of research requires increased emphasis in our efforts to prevent cancer.

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The sense of obligation is culturally modulated

Behavioral and Brain Sciences ◽

10.1017/s0140525x19002371 ◽

2020 ◽

Vol 43 ◽

Author(s):

Andrea Bender

Keyword(s):

Cultural Studies ◽

Cross Cultural ◽

Human Populations ◽

Cultural Group ◽

Target Article ◽

Sense Of Obligation ◽

Cross Cultural Studies

Abstract Tomasello argues in the target article that, in generalizing the concrete obligations originating from interdependent collaboration to one's entire cultural group, humans become “ultra-cooperators.” But are all human populations cooperative in similar ways? Based on cross-cultural studies and my own fieldwork in Polynesia, I argue that cooperation varies along several dimensions, and that the underlying sense of obligation is culturally modulated.

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Vitamin D Deficiency/Insufficiency and Challenges in Developing Global Vitamin D Fortification and Supplementation Policy in Adults

International Journal for Vitamin and Nutrition Research ◽

10.1024/0300-9831/a000117 ◽

2012 ◽

Vol 82 (4) ◽

pp. 237-259 ◽

Cited By ~ 9

Author(s):

Moshe Ben-Shoshan

Keyword(s):

Vitamin D ◽

Vitamin D Deficiency ◽

Search Strategy ◽

Epidemiologic Studies ◽

Vitamin D Supplementation ◽

Vitamin D Status ◽

Societal Burden ◽

Time Period ◽

New Guidelines ◽

In Cis

This review summarizes studies discussing vitamin D status in adults and reveals that vitamin D deficiency/insufficiency is highly prevalent in adults and that current fortification and supplementation policies are inadequate. Background and aims: Studies suggest a crucial role for adequate vitamin D status in various health conditions including bone metabolism, cancer, cardiovascular diseases, and allergies. However, relatively little is known about poor vitamin D status and unmet needs in adults. This report aims to highlight the contribution of epidemiologic studies (through the identification of health effects and societal burden) to the development of vitamin D fortification and supplementation policies and reveal unmet global challenges in adults. Methods: In order to assess worldwide vitamin D status in adults, the search strategy combined the medical literature database MEDLINE (using PubMed) for the time period between January 1, 1980 and February 28, 2011, using the key words vitamin D deficiency and insufficiency, and included articles in which access to full text was possible and in which healthy adults were assessed according to one of four commonly used vitamin D threshold classifications. Results: This report reveals that vitamin D deficiency occurs in 4.10 % [95 % CI (confidence interval), 3.93 %, 4.27 %] to 55.05 % (54.07 %, 56.03 %) of adults, while insufficiency occurs in 26.07 % (24.82 %, 27.33 %) to 78.50 % (77.85 %, 79.16 %), depending on the classification used. However, lack of overlap in CIs and high value of I2 statistics indicate considerable heterogeneity between studies. Further, certain populations (i. e. dark-skinned individuals, immigrants, and pregnant women) may be at higher risk for poor vitamin D status. Conclusion: Current policies for vitamin D supplementation and fortification are inadequate and new guidelines are required to improve vitamin D status in adults.

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A randomized cross-over trial in patients suspected of PAD on diagnostic accuracy of ankle-brachial index by Doppler-based versus four-point oscillometry based measurements

VASA ◽

10.1024/0301-1526/a000808 ◽

2019 ◽

Vol 48 (6) ◽

pp. 516-522 ◽

Cited By ~ 5

Author(s):

Verena Mayr ◽

Mirko Hirschl ◽

Peter Klein-Weigel ◽

Luka Girardi ◽

Michael Kundi

Keyword(s):

Diagnostic Accuracy ◽

Ankle Brachial Index ◽

Area Under The Curve ◽

High Volume ◽

Epidemiologic Studies ◽

Lower Sensitivity ◽

Oscillometric Device ◽

Specificity And Sensitivity ◽

Time Requirements ◽

Peripheral Arterial

Summary. Background: For diagnosis of peripheral arterial occlusive disease (PAD), a Doppler-based ankle-brachial-index (dABI) is recommended as the first non-invasive measurement. Due to limitations of dABI, oscillometry might be used as an alternative. The aim of our study was to investigate whether a semi-automatic, four-point oscillometric device provides comparable diagnostic accuracy. Furthermore, time requirements and patient preferences were evaluated. Patients and methods: 286 patients were recruited for the study; 140 without and 146 with PAD. The Doppler-based (dABI) and oscillometric (oABI and pulse wave index – PWI) measurements were performed on the same day in a randomized cross-over design. Specificity and sensitivity against verified PAD diagnosis were computed and compared by McNemar tests. ROC analyses were performed and areas under the curve were compared by non-parametric methods. Results: oABI had significantly lower sensitivity (65.8%, 95% CI: 59.2%–71.9%) compared to dABI (87.3%, CI: 81.9–91.3%) but significantly higher specificity (79.7%, 74.7–83.9% vs. 67.0%, 61.3–72.2%). PWI had a comparable sensitivity to dABI. The combination of oABI and PWI had the highest sensitivity (88.8%, 85.7–91.4%). ROC analysis revealed that PWI had the largest area under the curve, but no significant differences between oABI and dABI were observed. Time requirement for oABI was significantly shorter by about 5 min and significantly more patients would prefer oABI for future testing. Conclusions: Semi-automatic oABI measurements using the AngER-device provide comparable diagnostic results to the conventional Doppler method while PWI performed best. The time saved by oscillometry could be important, especially in high volume centers and epidemiologic studies.

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Self-Injurious Behavior vs. Nonsuicidal Self-Injury

Crisis ◽

10.1027/0227-5910/a000127 ◽

2012 ◽

Vol 33 (2) ◽

pp. 106-112 ◽

Cited By ~ 3

Author(s):

Christopher M. Bloom ◽

Shareen Holly ◽

Adam M. P. Miller

Keyword(s):

Positive Reinforcement ◽

Empirical Investigation ◽

High Stress ◽

Animal Research ◽

Stress Conditions ◽

Human Populations ◽

Pharmacological Interventions ◽

Self Injury ◽

Cns Stimulant ◽

Nonsuicidal Self Injury

Background: Historically, the field of self-injury has distinguished between the behaviors exhibited among individuals with a developmental disability (self-injurious behaviors; SIB) and those present within a normative population (nonsuicidal self-injury; NSSI),which typically result as a response to perceived stress. More recently, however, conclusions about NSSI have been drawn from lines of animal research aimed at examining the neurobiological mechanisms of SIB. Despite some functional similarity between SIB and NSSI, no empirical investigation has provided precedent for the application of SIB-targeted animal research as justification for pharmacological interventions in populations demonstrating NSSI. Aims: The present study examined this question directly, by simulating an animal model of SIB in rodents injected with pemoline and systematically manipulating stress conditions in order to monitor rates of self-injury. Methods: Sham controls and experimental animals injected with pemoline (200 mg/kg) were assigned to either a low stress (discriminated positive reinforcement) or high stress (discriminated avoidance) group and compared on the dependent measures of self-inflicted injury prevalence and severity. Results: The manipulation of stress conditions did not impact the rate of self-injury demonstrated by the rats. The results do not support a model of stress-induced SIB in rodents. Conclusions: Current findings provide evidence for caution in the development of pharmacotherapies of NSSI in human populations based on CNS stimulant models. Theoretical implications are discussed with respect to antecedent factors such as preinjury arousal level and environmental stress.

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The Effect of Alternative Scoring Procedures on the Measurement Properties of a Self-Administered Depression Scale

European Journal of Psychological Assessment ◽

10.1027/1015-5759/a000371 ◽

2019 ◽

Vol 35 (1) ◽

pp. 55-62 ◽

Cited By ~ 1

Author(s):

Noboru Iwata ◽

Akizumi Tsutsumi ◽

Takafumi Wakita ◽

Ryuichi Kumagai ◽

Hiroyuki Noguchi ◽

...

Keyword(s):

Classical Test Theory ◽

Depression Scale ◽

Psychometric Testing ◽

Epidemiologic Studies ◽

Test Theory ◽

Measurement Properties ◽

Irt Model ◽

Response Alternatives ◽

Polytomous Item Response ◽

Θ Point

Abstract. To investigate the effect of response alternatives/scoring procedures on the measurement properties of the Center for Epidemiologic Studies Depression Scale (CES-D) which has the four response alternatives, a polytomous item response theory (IRT) model was applied to the responses of 2,061 workers and university students (1,640 males, 421 females). Test information functions derived from the polytomous IRT analyses on the CES-D data with various scoring procedures indicated that: (1) the CES-D with its standard (0-1-2-3) scoring procedure should be useful for screening to detect subjects with “at high-risk” of depression if the θ point showing the highest information corresponds to the cut-off point, because of its extremely higher information; (2) the CES-D with the 0-1-1-2 scoring procedure could cover wider range of depressive severity, suggesting that this scoring procedure might be useful in cases where more exhaustive discrimination in symptomatology is of interest; and (3) the revised version of CES-D with replacing original positive items into negatively revised items outperformed the original version. These findings have never been demonstrated by the classical test theory analyses, and thus the utility of this kind of psychometric testing should be warranted to further investigation for the standard measures of psychological assessment.

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