Background. Most schools in Ibadan, Nigeria, are located near major roads (mobile line sources). We conducted an initial assessment of noise levels and adverse noise-related health and learning effects. Methods. For this descriptive, cross-sectional study, four schools were selected randomly from eight participating in overall project. We administered 200 questionnaires, 50 per school, assessing health and learning-related outcomes. Noise levels  were measured with calibrated sound level meters. Traffic density was assessed for school with the highest measured dBA. Observational checklists assessed noise control parameters and building physical attributes. Results. Short-term, cross-sectional school-day noise levels ranged 68.3–84.7 dBA. Over 60% of respondents reported that vehicular traffic was major source of noise, and over 70% complained being disturbed by noise. Three schools reported tiredness, and one school lack of concentration, as the most prevalent noise-related health problems. Conclusion. Secondary school occupants in Ibadan, Nigeria were potentially affected by exposure to noise from mobile line sources. Recently, noise pollution has been of increasing concern worldwide, particularly in most urban centers. The noise problems of the modern industrial societies seem incomparable to the past given the larger sources of noise now present outdoors and indoors. According to the World Health Organization , trafficLike the home and the work place, school is also an important microenvironment. The school is important for the cognitive, creative, and social development of children. Schools are therefore expected to ensure the best possible conditions for a child's physical and intellectual development, including control of excess environmental noise.Noise levels are measured in decibels (dB). One decibel is the threshold of hearing. Approximately 60 dB is the level of normal talking. According to WHO , the perMeasurements in A-weighted dB (dBA) assess loudness and compensate for the human ear's lower sensitivity to lower frequency and very high-frequency sounds . Noise h Studies carried out in industrialized country cities such as in the European Union have suggested that children living and attending schools near airports, elevated trains, and highways suffer distractions, lack of concentration, and restlessness, resulting in poor scores and lower productivity in their academic performances as compared to their peers in less noisy environments –14. In LThe objective of this pilot study was to initially assess cross-sectional indoor and outdoor environmental noise levels and noise-related health and learning outcomes including symptoms at urban schools in an LDC in Africa. We focused on selected secondary schools in the city of Ibadan, an indigenous highly populated and still developing and sprawling urban area in southwestern Nigeria, West Africa. Most schools are near major roadways with automobiles, buses, and large trucks and oil tankers.This study went through proper required institutional review board procedures at the College of Medicine, University of Ibadan prior to its initiation. Informed consent was obtained from participating study schools.We conducted the overall study in eight secondary schools; this paper focused on selected noise and health and learning related data from four study schools. We received permission to refer to schools by acronyms as defined below.Ibadan is the capital of Oyo State in Nigeria and one of the largest cities (metropolitan areas) in West Africa, with millions of inhabitants. Ibadan is an old, primarily indigenous African city situated between latitude 7° and 9°30′ east of prime meridian. Ibadan covers a large land area of about 12 square kilometers at an altitude ranging from about 150 to over 200 meters with isolated ridges and peaks rising over about 270 meters. Ibadan presents a typical picture of many African cities each known for having the old town area (inner core) and then the transitional and peripheral areas. Most people are Yoruba; other ethnic groups constitute smaller proportions of the population. Ibadan has over 300 academic settings comprised of public and private nursery, primary schools and secondary schools as well as a university.The study was a descriptive cross-sectional survey involving field measurements of environmental noise levels at specific recorded geographic coordinates.The overall study population included students above 14 years of age in eight senior secondary schools, especially classes I, II, and III . A combination of stratified and simple random sampling was employed in getting the appropriate sample population for the study described in this paper. Data collection was conducted in four of the eight secondary schools selected in our overall study. The four schools, which are located in metropolitan Ibadan, were Ikolaba Grammar School (Ikolaba or IGS), Oba Akinbiyi High School (Oba Akinbiyi or OAHS), Anglican Commercial Grammar School (Anglican or ACGS), and Bashorun Ojoo High School (Bashorun Ojoo or BOHS). A total of 400 participants were included in the study, 50 from each of the eight study schools.Well structured questionnaires including a technician walk through or observational check list were administered to collect data related to environmental and health and learning related issues, with a focus on noise and its sources located outdoors and indoors. These were based on previous school-based research in the USA including quantitative and qualitative measurements related to noise loudness and/or frequency –17 and eThe questionnaires consisted of both open and closed ended questions with five sections. The sections were section A for general information about the schools; section B for sociodemographic data on participants, section C for occupational and learning related features of the schools and classrooms, section D for environmental characteristics; and, section E for assessing health and learning related conditions (symptoms). Questionnaires were self administered except for section D, which was an observational checklist used by field technicians to assess the environmental health indicators inside and outside the school environments.The noise levels were measured using a factory-calibrated TECPEL Model 330 series sound level meter (SLM) set at the slow response mode with A-weighting (A-weighted decibels (dBA)). The measurements were conducted twice, between 9:00-10:00 AM in the morning and 1:00-2:00 PM in the afternoon. Measurements were conducted at two points in the classroom, including where students were seated, and on the play ground. We recorded these data daily for a period of five school days, that is, one full week.A hand-held, battery-powered factory calibrated global positioning system (GPS) was used to determine the geographic coordinates of the school locations and this study's noise measurements. Traffic density, or the manual count of the number of vehicles , around the school with the highest noise levels was also determined during the study period. The classroom dimensions—floor space and the sizes of potentially open doors and windows—were also determined (data not reported here) because outdoor sources of air and noise pollution are well known to impact indoor environments in urban and rural areas worldwide.Data from completed questionnaires were entered in Microsoft Excel spreadsheets and then were imported into the SPSS statistical software package for analyses. Frequency distribution tables and other descriptive statistics such as numbers and percentages were used to summarize study data in both tabular and graphical formats.2 with ≥2 m between the teacher and front row [The general information—including some geographical and physical characteristics—obtained about the study schools and classroom buildings isa presented in ront row —and had Our data presented in The impact of noise on children's health and development in schools is of major public health concern. This could be greatly reduced if noise problems were taken into consideration as early as possible when a school is being designed. Environmentally sustainable buildings designed to enhance resource conservation and indoor air and environmental quality, including minimizing noise, assist education goals.Each of the four study schools was sited close to main roads, which potentially exposed students to excess and high levels of noise from vehicular traffic, from intermittent use of vehicle horns, from the tires during the sudden use of brakes, and so forth, relative to their individual proximities to the road both inside and outside of buildings (classrooms). We note that noise control devices like absorbers , reflectors, and attenuators were absent in schools studied.From a comparative perspective, BOHS reported a lack of concentration as the most prevalent health and learning related noise problem (84%). IGS, OAHS, and ACGS, however, reported tiredness as their most prevalent health and learning related noise problem at 60%, 44%, and 66%, respectively. The results obtained and their variations may be traced to the fact that most of the schools are located close to main roads and are readily affected by the noise from vehicle engines in degrees dependant on their individual proximities to the road—mean levels measured during this study indoors and outdoors were between 68.3 dBA and 84.7 dBA.The cross-sectional mean noise levels measured in this study, though limited with respect to longer-term exposure dose for surveyed students, are proper representations, that is, estimates, of acute (if large or episodic) and/or chronic (continuous or intermittent) exposures experienced by students attending and adults working at secondary schools in this setting. These estimated exposures are capable of initiating and aggravating noise-induced hearing impairment as well as nonauditory health effects specified by WHO 2000) we selected to include in our pilot study. This pilot study's findings also appeared to be consistent with recently completed European Commission funded studies, which investigated road traffic and aircraft noise exposure and potential impacts on child cognition and health as well as the role of a child's increased sensitivity 00 we sel. ExposurFurthermore, our observed absence of noise control measures and devices in the four study schools could also be responsible for the high reported prevalence of health and learning related outcomes. The impact of noise on children's health and development in schools imposes a potentially considerable financial burden, which could be greatly reduced if noise concerns were taken into consideration as early as possible when a school is being planned as well as during operations and maintenance of the buildings and facilities.This study measured cross-sectional, shorter-term dBA, or loudness, to assess potential exposure at schools to noise. However, though dBA correlates well with human judgment of relative loudness, the metric does not correlate as well with human judgment of relative noisiness or subjective sound quality, that is, comparing sounds with distinct spectral or tonal characteristics including frequency . High-frAs Nigeria strives towards achieving adequate health care for the populace, the school and learning environment must not be neglected. This study suggested that noise levels indoors (classrooms) and outdoors (playgrounds) across schools were higher than WHO permissible levels for community learning environments. The most reported health problems potentially associated with acute (large or episodic) and/or chronic (continuous or intermittent) exposure to noise within the school environment were lack of concentration and tiredness. Evidence has suggested that noise in learning environments has considerable effects on the learning abilities and the general productivity of children in terms of their academic performance as compared to children in serene learning environments. Therefore, this study should inform future, more rigorous longitudinal research with repeated measures across seasons, indoors and outdoors, in Nigerian schools as well as collaborative efforts by government agencies and education stakeholders for policy formulation and implementation. The goal is to promote enhanced learning environments for children free from excess environmental noise, which will also assist the productivity and improve the health of adult staff.


Special Collection “Stress-Induced Depression and Comorbidities: From Bench to Bedside,” published in this issue of PLoS ONE. The Overview encompasses the problematic diagnosis of MD, as well as preclinical evidences linking genetic predisposition, early life events and social factors, imbalanced HPA axis, molecular pathways within the central nervous system, and metabolic comorbidities with depression-like disorders. It is emphasized how the link between stress and depression can be deeper than previously recognized, following the description of a potentially common depression subtype, named tentatively “stress-induced depression” (STRID). Due to the inherent biological perspective underlying the STRID concept, both preclinical and clinical research will be pivotal in clarifying the validity of this new subtype of MD and in improving predictors for treatment response, and will provide a better basis for genetic studies as well as stimulating new drug discovery programs.Major depression (MD) is a severe, life-threatening, and highly prevalent psychiatric disorder, predicted to soon become one of the major causes of death worldwide. Despite extensive investigations, the exact mechanisms responsible for MD have not been identified. This Overview focuses on the role of stress in depression. It discusses current advancements in biological psychiatry, neuroscience, and neuroendocrinology, highlighting key findings presented in the research papers included in the Major depression (MD) is a severe, life-threatening, and widespread psychiatric disorder having an incidence of about 340 million cases worldwide. MD ranks fifth among leading causes of global disease burden including developing countries, and by year 2030 it is predicted to represent one of the three leading causes of burden of disease worldwide Special Collection “Stress-Induced Depression and Comorbidities: From Bench to Bedside,” published in this issue of PLoS ONE.Understanding MD in its etiology and biological phenomenological characteristics could improve its recognition and treatment Diagnostic and Statistical Manual (DSM-IV) classification ignores etiology, and distinguishes between bipolar and unipolar conditions, and within the unipolar group between cases with and without melancholia, or with and without psychotic symptoms, as well as atypical depression. In addition, the current diagnostic criteria represent clusters of symptoms and characteristics of clinical courses that do not necessarily describe homogenous disorders and may rather reflect common final pathways of different pathological processes DSM classifications Presently accepted diagnostic criteria for MD Although no single gene could be responsible for a complex and multifactorial disorder like MD, association and pharmacogenetic studies identified a number of loci associated with vulnerability to MD or antidepressant efficacy G×E effects are easily accessible for preclinical investigations, and the elevated number of inbred strains of mice  available offers a powerful experimental tool. In this respect, Schweizer and coworkers Collection a potential role for some inflammatory mediators in a cohort of patients under prolonged psychosocial stress, providing further epidemiological support (results discussed above in this Overview).Stress is usually defined as a state of disturbed homeostasis inducing somatic and mental adaptive reactions, globally defined as “stress response,” aiming to reconstitute the initial homeostasis or a new level of homeostasis after successful adaptation, i.e., allostasis Collection, van der Laan and coworkers in vivo a critical time window may exist for effective repression of the CRH gene and HPA axis by glucocorticoids.One of the hallmarks of the stress response has long been considered the activation of the HPA axis. Hypothalamic CRH activation is a pivotal signaling molecule in the regulation of the HPA axis in particular and of the stress response in general. Therefore, comprehension of the mechanism responsible for the negative feedback regulation of CRH is of paramount importance. In the present CollectionKnowledge on the functioning of the HPA axis under acute or chronic challenge is also a key to understanding the intimate link between stress response and the pathogenesis of depression DSM-IV identifies specific behavioral and cognitive diagnostic criteria for MD patients. Among these, depressed mood, anhedonia, locomotor disturbances, and anxiety are accessible for preclinical investigation, while others such as feelings of worthlessness and thoughts of death or suicide cannot be reliably mimicked in animal models. A number of animal models have been developed and validated Special Collection of PLoS ONE make use of chronic or intermittent models of stress Collection also describe animal models that are increasingly being regarded as the most promising to model etiological factors and key features of MD patients, i.e., i) models in which the threatening stimulus is social in nature The Collection further clarifies that at least some behavioral disturbances present in MD diagnostic criteria can be reliably induced and experimentally determined in animals models, including for anhedonia From a nosological point of view, original research presented in the A similar ameliorating effect on stress coping has also been determined by Collins and coworkers omics evidences into experimentally based results . For example, the “sequenced treatment alternatives to relieve depression” (STAR*D) clinical trial identified several loci associated with response to anti-depressants and suicidal ideation in MD patients In the postgenomic era, high-throughput techniques allow the identification of genes overexpressed or downregulated in selected brain regions after chronic stress exposure or in MD. Following these observations, researchers now aim at translating According to the examples above, it can be concluded that changes in gene expression and their association with behavioral traits or psychopathologies remain among the more powerful experimental tools to uncover the mechanisms leading to a brain disorders. In addition, recent findings demonstrate that complex “epigenetic” mechanisms, which regulate gene activity without altering the DNA code, have long-lasting effects within mature neurons Another fruitful research area in biological psychiatry is the link between neural plasticity, MD, and antidepressants DSM-IV indicates as diagnostic criteria increased or diminished appetite/body weight which should represent a change from pre-MD onset. Most animal models including several discussed in the present CollectionCollectionIn addition to neuroanatomical changes, MD is also associated with severe vegetative and biological disturbances, including sleep and eating disorders, body weight changes, and neuroendocrine abnormalities. The PLoS ONE Collection discussed here. The link between stress and depression is not novel, and several authors have aimed at identifying new subtypes of depression based on their functional link with stress exposure , recently described in Sweden by Åsberg and coworkers http://www.scb.se). Studies of consecutive cases with psychiatric diagnoses culled from the databases of two large Swedish insurance companies showed that about 80% of patients met DSM-IV criteria for MD . The depression episodes were mild to moderate (MADRS <20), and accompanied by significant working memory impairment The notion that stress may cause depression has been an underlying concept in the choice of papers included in the re e.g., . Of specSpecial Collection of PLoS ONE propose an integrated effort on how to move in the direction of joint studies. Both preclinical and clinical research will be pivotal in clarifying the validity of this new subtype of MD, in improving predictors for treatment response, and in providing a better basis for genetic studies, as well as in stimulating new drug discovery processes.Overall, the studies presented in this


Public health systems have relied on public health surveillance to plan health programs, and extensive surveillance systems exist for health behaviors and chronic disease. Mental health has used a separate data collection system that emphasizes measurement of disease prevalence and health care use. In recent years, efforts to integrate these systems have included adding chronic disease measures to the Collaborative Psychiatric Epidemiology Surveys and depression measures to the Behavioral Risk Factor Surveillance System; other data collection systems have been similarly enhanced. Ongoing challenges to integration include variations in interview protocols, use of different measures of behavior and disease, different interval reference periods, inclusion of substance abuse disorders, dichotomous vs continuous variables, and approaches to data collection. Future directions can address linking surveillance efforts more closely to the needs of state programs, increasing child health measurements in surveys, and improving knowledge dissemination from survey analyses. Preventing Chronic Disease addresses the challenges of mental health and mental illness in the public health setting. According to the World Health Organization (WHO), mental illnesses account for more collective disability burden in developed countries than any other group of illnesses, including cancer and heart disease  National Health Interview Survey (NHIS), the National Health and Nutrition Examination Survey (NHANES), and the Behavioral Risk Factor Surveillance System (BRFSS); the Agency for Healthcare Research and Quality's Medical Expenditure Panel Survey; the Substance Abuse and Mental Health Services Administration's (SAMHSA's) National Survey on Drug Use and Health (NSDUH); and in the National Science Foundation's Panel Study of Income Dynamics .Healthy People 2010 objectives and as benchmarks for rates of specific lifetime and previous 12-month mental disorders such as mood, anxiety, and impulse control disorders.Epidemiologic surveys of mental illness, first published by analyzing army recruits in 1942, have been expanded to national populations with the Epidemiologic Catchment Area Study of 1980-1985, the National Comorbidity Survey of 1990-1992, and the National Comorbidity Survey Replication (NCS-R) of 2001-2003 . The ColUnderstanding the relationship between mental illness and chronic disease is vital to public health assessment and health care delivery. The primary surveillance tool for assessing state-based estimates of health risk behaviors, chronic disease preventive services, and health care access is the BRFSS. The BRFSS is a random-digit–dialed survey of noninstitutionalized people aged 18 years or older, and systems are now in development for expanding its reach. These systems include call-back surveys, special population oversampling, and use of cell phone telephone numbers and paper surveys. BRFSS is unique in that it provides data at the state, county, and metropolitan and micropolitan statistical area levels.Starting in 2006, state health departments, in collaboration with CDC and the Center for Mental Health Services at SAMHSA, implemented mental illness questions on the BRFSS. From 2006 to 2009, mental health modules have been included in the BRFSS in many states. The Patient Health Questionnaire 8 (PHQ-8), which screens for depressive symptoms, was administered by 41 states and territories in 2006 and 16 states in 2008. The Kessler 6 (K-6) scale, which examines nonspecific psychological distress, was administered in 37 states and territories in 2007 and continues implementation in 2009. Integrated analysis of mental health and other health issues has shown significant associations between mental illness and health risk behaviors , chronic disease , and lower levels of preventive care. The BRFSS is among the first surveillance systems that allow population-based state and local estimates for mental and physical health, which are critical for policy and programs at the state and community levels.Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition) mental disorder that resulted in functional impairment, who also have poor physical health, are more likely to have poor functional outcomes and lower levels of satisfaction with their mental health care . This improved surveillance indicates that people with serious mental illness (SMI), defined as having a DSM-IV  NHANES, each of the survey instruments listed contains the K-6 nonspecific psychological distress scale, which is also included in the CPES benchmark studies. This "common currency" approach to instrumentation facilitates general comparisons among studies; however, variations among survey instruments and methods must be considered when interpreting data from different sources.The ways different surveys define and measure mental illnesses often vary. One approach uses interview protocols that ask various symptom, duration, and frequency questions for specific mental disorders, on the basis of classification systems such as the DSM or the International Classification of Diseases (ICD) systems. For example, depression may be measured by using the WHO Composite International Diagnostic Interview (CIDI) depression module, an instrument designed for use in general population surveys, or the PHQ, an instrument designed for use in clinical settings but also used in some health surveys. The WHO CIDI approach provides considerable detail at the national level about specific disorders but requires extensive resources to complete. The PHQ-2, PHQ-8, and PHQ-9, validated measures for depressive symptoms in wide use in clinical care, are sufficiently brief to be included in population-based surveys and public health awareness campaigns.Another approach is to use different mental health measures to assess "any mental disorder" (as opposed to a specific disorder) by using nonspecific measures of psychological function. These brief scales, commonly found in large, population-based surveys, can be used to identify subpopulations with a high likelihood of having any mental illness. For example, the K-6 scale was originally developed for use in the NHIS as a measure of nonspecific psychological distress  during the past 30 days. SAMHSA then supported a pilot study to determine whether a version of the K-6 that assessed distress in the past year could identify SMI cases in the general population . In 2008Another distinction is the reference period, which differs among data collection systems. Serious psychological distress, which is defined as having a K-6 score of 13 or higher during 1 month in the past 12 months, is determined in the NSDUH with the use of a past-year reference period and past-30-day reference period (since 2008). NHIS and BRFSS use a past-30-day reference period only. Different reference periods  are also found in disorder-specific measures (such as depression), depending on the purpose of the study. The reference period used has a substantial effect on the prevalence rate yielded, not only because the estimates may be subject to recall bias but also because longer reference periods may result in a larger number of affirmative responses.Other approaches to assessing mental illness have depended on the presence of functional impairments and still others on whether there is a history of treatment. Surveys vary as to the inclusion or exclusion of substance use disorders and cognitive disturbances, such as dementia, under a broader umbrella of mental disorders. These variations in mental illness definitions have provided data on overlapping but nonidentical populations.Another issue in mental health surveillance is whether specific or nonspecific disorders and associated impairments are measured continuously or dichotomously. Dichotomous measures indicate whether a specific threshold or cutpoint was reached. In contrast, using a continuous measure may allow mild, moderate, and severe levels of disorder to be identified. Studies have shown that untreated minor depression or residual subthreshold depressive symptoms after treatment are often associated with disability and poor psychosocial functioning and a potentially more severe, relapsing, and chronic course that requires additional treatment .The method of data collection may also affect comparability. For example, while most data are collected via computer-assisted interviews, some surveys are self-administered , and others are administered by an interviewer in the home or on the telephone. These differences affect survey responses, particularly for mental health questions and sensitive items such as illegal or embarrassing behavior .We have focused on existing efforts in mental illness surveillance but recognize the value of monitoring the prevalence and correlates associated with psychological well-being, as discussed by Manderscheid et al in this issue . Future Surveillance efforts can be more meaningfully linked to state and local health policy and program development efforts. Ongoing, multiyear inclusion of mental health modules in state and local level surveys may permit state epidemiologists to monitor the effects of community health partner efforts. We must also develop culturally meaningful surveillance of mental health and mental illness in specific populations, such as ethnic minorities, veterans, parents, caregivers, and people who are disabled.A lifespan approach to mental health and mental illness will facilitate a better understanding of the natural course of mental illness and its effect on overall health. Most surveys focus on adults and include few measures of child health. Studies of mental health and mental illness in younger populations are relevant to the development of prevention strategies applied at the earlier stages of development.Evidence-based care is the gold standard for health care providers, but we lack a systematic approach to monitor effectiveness of treatment for mental disorders. Data on medications, unmet needs for mental health services, and outcomes such as employment, housing stability, and consumer satisfaction are available ,19. HoweKnowledge dissemination is a critical aspect of surveillance, but natural lines of communication in public health and in mental health have generally been separate; information has typically been disseminated from CDC to state and local public health infrastructure and health care providers, and from SAMHSA to state mental health authorities, mental health advocacy organizations, and mental health providers. Systems should be developed so information from an integrated mental health and physical health surveillance system can be directed broadly to specialty mental health and substance abuse providers, public health systems, community health providers, and community health promotion programs.In the past decade we have moved from a tradition of separate mental health and public health surveillance efforts to an increasingly integrated approach. Agencies in the US Department of Health and Human Services are collaborating to create new systems and expand existing ones. These systems monitor mental illness by incorporating common mental health measures in ongoing federal surveys, conducting large psychiatric epidemiology benchmark surveys, and facilitating health risk factor surveillance surveys that include mental health variables at the state and local levels. Substantive elements of a mental health surveillance system exist today, although there is work to be done to make an integrated approach standard practice.Surveillance has focused largely on established disease or symptoms, but collection of additional data on resilience, coping skills, protective factors, and aspects of positive mental health are considerations in devising strategies for disease prevention and mental health promotion. Maintaining focus on the overall health of our population will be critical in the next decades, as will leaving behind the commonly accepted divide between mental and physical illnesses, "despite the fact that both exist within individuals in an exquisitely integrated fashion" . An opti


To examine the primary risk factor for oral cancer in the US, smoking and tobacco use, among the specific US states that experienced short-term increases in oral cancer incidence and mortality.Population-based data on oral cancer morbidity and mortality in the US were obtained from the National Cancer Institute's (NCI) Surveillance, Epidemiology, and End Results (SEER) database for analysis of recent trends. Data were also obtained from the Centers for Disease Control and Prevention (CDC) Behavioral Risk Factor Surveillance System (BRFSS) to measure current and former trends of tobacco usage. To comprehensive measures of previous state tobacco use and tobacco-related policies, the Initial Outcomes Index  and the Strength of Tobacco Control index  were also used for evaluation and comparison.Analysis of the NCI-SEER data confirmed a previous report of geographic increases in oral cancer and demonstrated these were state-specific, were not regional, and were unrelated to previously observed increases among females and minorities. Analysis of the CDC-BRFSS data revealed these states had relatively higher percentages of smokers currently, as well as historically. In addition, analysis of the IOI and SoTC indexes suggest that many factors, including cigarette pricing, taxes and home or workplace bans, may have had significant influence on smoking prevalence in these areas. Trend analysis of these data uncovered a recent and significant reversal in smoking rates that suggest oral cancer incidence and mortality may also begin to decline in the near future.Due to the rising costs of health care in the US and the limited resources available for health prevention efforts, it is essential to organize and direct more effective efforts by public health officials and epidemiologists, as well as funding from local, state and federal governments, to reduce and eliminate identified health disparities. This study provides evidence how these efforts may be directed to specific geographic areas, and towards the white males, previously thought to be unaffected by the increases in oral cancer among females and minorities. Although oral cancer incidence and mortality rates have increased worldwide, these rates have been slowly and steadily declining among the US population over the past thirty years ,2. DespiOral cancer incidence and mortality are correlated strongly with two major risk factors, tobacco use - consisting primarily of smoking in the US, and to a lesser extent, heavy alcohol use, which together account for the overwhelming majority of cases . A recenA review of oral cancer epidemiology in Europe revealed morbidity and mortality have been steadily decreasing since the early 1980s, similar to the trends observed in the US . TemporaThis study sought to examine the primary risk factors for oral cancer, focusing specifically on tobacco use and smoking prevalence, among the US states recently found to have increasing short-term oral cancer incidence and mortality rates, including Nevada, North Carolina, Iowa, Ohio, Maine, Idaho, North Dakota and Wyoming . More spPopulation-based data on oral cancer in the US were obtained from the Surveillance, Epidemiology, and End Results (SEER) program. SEER provides cancer incidence and survival data from population-based cancer registries, representing approximately 25% of the US population . All oraRecent trend data in death rates from oral cancer in individual US states were calculated by the National Cancer Institute (NCI) SEER*Stat using data provided by the National Vital Statistics System public use data file (SEER) and from the State Cancer Registries using the Joinpoint Regression program and are expressed as the annual percent change (APC) over the reported trend period  for selected US states. These states included Nevada (NV), North Carolina (NC), Iowa (IA), Ohio (OH), Maine (ME), Idaho (ID), North Dakota (ND), Wyoming (WY), Arizona (AZ), California (CA), Oregon (OR) and Utah (UT). Trends calculated using the Joinpoint Regression statistical software program model the natural logarithm of the rates, identifying years at which any given trend changes, connecting these years graphically by a series of straight line segments [Historical risk behavior data for tobacco use from selected US states were obtained from the Behavioral Risk Factor Surveillance System (BRFSS). BRFSS is among the largest health surveillance and survey systems, responsible for tracking data monthly and reporting health conditions and risk behaviors from all US states, the District of Columbia, Puerto Rico, the U.S. Virgin Islands, and Guam, since 1984 . BRFSS iz scores were calculated and summed to form a tobacco control IOI, which was correlated with adult smoking prevalence and the point estimate of per capita cigarette consumption. Similarly, state-specific data and rankings from 1999-2000 form the standardized Strength of Tobacco Control (SoTC) index, which were also obtained from previous reports [State-specific data and rankings that form the US State Tobacco Control Initial Outcomes Index (IOI) were obtained from a previous report . Measure reports ,24. PosiOral cancer rates in those selected states with previously identified increasing APC  were recTo determine if these trends were restricted to these particular states or if they are part of a larger regional increase, oral cancer rates for US states with contiguous geographic borders to Nevada were analyzed to determine any demonstrable changes Fig . This anEpidemiologic evidence has previously demonstrated oral cancer incidence and mortality rates are correlated strongly with two major risk factors, tobacco use - consisting primarily of smoking, and to a lesser extent, heavy alcohol use . To asseAlthough current smoking rates may indicate state-specific usage for tobacco based on price, availability or other social and economic factors, current oral cancer mortality rates are generally the result of previous smoking prevalence . Recent Another comprehensive measure of previous state tobacco usage, known as the strength of tobacco control (SoTC), was subsequently developed by public health officials to rank and compare all US states in 1999 and 2000, similar to the IOI. Once again, an analysis of the SoTC index data revealed the majority of states with increasing oral cancer APC earned negative SoTC scores, with Nevada scoring the lowest (-1.42), suggesting that tobacco control in these states remained comparatively weak and less than the national mean index   Figure . In addiTo determine any changes in smoking prevalence occurring in the states examined so far, BRFSS data for all available years 1995-2007) were obtained and short-term changes in smoking rates were evaluated to uncover any significant trends , or by pharmacologic means to prevent rejection of tissue, have increased in prevalence within the US during these same time periods, although their recognized influences on the development of oral cancers have been the subject of relatively fewer epidemiologic investigations ,29. AddiFinally, additional studies examining other modulating factors for oral cancer development have identified potential risk factors that may also influence overall rates, incidence, and mortality. Some studies have demonstrated an inverse relationship between the consumption of fruits or vegetables and oral cancer risk, indicating that dose-dependent reductions in oral cancer risk are possible with each additional serving of fruits or vegetables consumed -38. MoreDue to the rising costs of health care in the US and the limited resources available for health prevention efforts, it is essential to organize and direct more effective efforts by public health officials and epidemiologists, as well as funding from local, state and federal governments, to reduce and eliminate identified health disparities. This study provides evidence of state-specific increases in oral cancer that are not associated with the increases previously observed among females and minorities, thereby providing new insights regarding potential methods to identify changes in relevant trends in geographic areas which may experience increases in tobacco-induced diseases in the future. As state and local public health professionals strive to formulate effective prevention and education programs for their residents, understanding the relationships between cause and effect, as well as the primary or secondary factors that more accurately indicate the potential for increased risk, becomes more imperative.KK was responsible for the overall design and concept of this study. AB, NP, NR and KS were responsible for data collection and preliminary data analysis. AB and KK were primarily responsible for the writing, while SO and MC were responsible for the majority of editing. All authors have read and approved the final version of this manuscript.The authors declare that they have no competing interests.


Traditional hazards such as poor sanitation currently account for most of Africa’s environmentally related disease burden. However, with rapid development absent appropriate safeguards for environment and health, modern environmental health hazards (MEHHs) may emerge as critical contributors to the continent’s disease burden. We review recent evidence of human exposure to and health effects from MEHHs, and their occurrence in environmental media and consumer products. Our purpose is to highlight the growing significance of these hazards as African countries experience urbanization, industrial growth, and development.We reviewed published epidemiologic, exposure, and environmental studies of chemical agents such as heavy metals and pesticides.p,p′-dichlorodiphenyltrichloroethane (DDT) and organophosphates. Land and water resource pollution and industrial air toxics are areas of significant data gaps, notwithstanding the presence of several emitting sources.The body of evidence demonstrates ongoing environmental releases of MEHHs and human exposures sometimes at toxicologically relevant levels. Several sources of MEHHs in environmental media have been identified, including natural resource mining and processing and automobile exhaust. Biomonitoring studies provided direct evidence of human exposure to metals such as mercury and lead and pesticides such as Unmitigated MEHH releases and human exposure have implications for Africa’s disease burden. For Africans encumbered by conditions such as malnutrition that impair resilience to toxicologic challenges, the burden may be higher. A shift in public health policy toward accommodating the emerging diversity in Africa’s environmental health issues is necessary to successfully alleviate the burden of avoidable ill health and premature death for all its communities now and in the future. According to the World Health Organization (WHO), about one-third of Africa’s disease burden is attributable to environmental hazards . The majMEHHs are products of rapid development in the absence of health and environment safeguards, as well as the unsustainable consumption of natural resources . MEHHs iIn this review, we highlight the increasing significance of MEHHs as a public health issue in Africa using several lines of evidence, in no particular order: the presence of development-related activities  that are capable of generating these hazards; evidence of the occurrence of these types of hazards in environmental media as a result of development activities; evidence of human exposure to some of these hazards; and evidence of adverse effects among African populations. We weave these lines of evidence through chemical- specific examples such as toxics from industrial activity, air pollution from automobiles, and pesticides from modern agricultural practices. Our focus on chemical hazards is solely based on the relative preponderance of data for these types of hazards and is therefore very narrow in terms of the scope of possible MEHHs that are products of development. Accordingly, this is not a comprehensive review of all MEHHs in Africa. However, it more than suffices for our goals for this review, which are to demonstrate that MEHHs are increasing in significance as an environmental health concern, and also to emphasize the need for these hazards to occupy a priority spot in Africa’s public health and policy agenda.Mercury, in several forms, is a known neurotoxin that causes cognitive deficits at low exposure levels and severe neurologic effects at very high levels of exposure. Hg also exerts toxic effects on other organ systems, notably, the kidneys and the cardio vascular and immune systems. A detailed review of the range of toxic effects associated with exposure to different forms of Hg has been published previously . An impon = 500) to 50% in Mali . They also estimate that > 3,000 children are directly employed in artisanal mining in Tanzania. Children engaged in artisanal mining cut across a wide range of ages. In a 1998 survey summarized by Exposure to Hg in artisanal mining is a particularly important public health issue because of the demographics of the industry: Women and children are engaged in gold mining, and their involvement spans all possible activities, including those associated with the highest risks of Hg exposure. In the Kedougou region of Senegal, the involvement of women and children ranges from ore extraction to burning amalgam, and in the Tenkoto region, the process of amalgamation is carried out by women, within the vicinity of their young children . In Gaouin vivo distribution is similar to that of organic Hg; and it is readily transferred through the placenta and blood–brain barrier because of its lipophilicity . Performance on tests such as pencil tapping and matchbox tests, which evaluate neuromotor function, was also statistically significantly poorer in exposed children  and discussed extensively elsewhere . Unfortuhilicity . Clinicachildren .http://www.ehponline.org/members/2009/0800126/suppl.pdf)]. Overall, these studies demonstrate elevated body burdens of Hg in exposed populations such as miners, workers involved in ore processing, and even children residing in mining communities. In one study of gold miners in Kadoma, Zimbabwe, the highest Hg exposures occurred in amalgam burners relative to other workers   and behahttp://www.ehponline.org/members/2009/0800126/suppl.pdf)].The sources of Pb with the highest risk of exposure in Africa include deteriorated house paint, leaded gasoline, mining operations, polluted water, and contaminated foods and cosmetics . Other iUntil recently, leaded gasoline was the key source of widespread population exposure in urbanized parts of Africa. With its elimination from all of sub-Saharan Africa in 2007 , sourcesn = 239) had at least one Pb-based paint sample . In the southwestern city of Ibadan, Nigeria, almost all (96%) samples (n = 25) of glossy paints manufactured and sold locally had Pb content ≥ 600 ppm ]. These studies are representative of exposures primarily in rural and occupational settings and, in one case report , a breakdown product of the pesticide p,p′-dichlorodiphenyltrichloroethane (DDT), has also been detected in environmental media. The frequent reporting of organochlorines in the environment does not necessarily imply that organochlorine pesticides are the most used in Africa, but it may reflect their persistence in the environment and scientific interest in this class of compounds. In fact, carbamates, organophosphates, and pyrethroids, which are less persistent in the environment, are also widely used for agricultural purposes.The footprints of pesticide use in Africa are evident in food and environmental media. For example, pesticides used in agriculture have been detected in streams, rivers, and sediments that are located within the vicinity of farms in different regions of Africa , 2001b. Schulz  are sprayed indoors to reduce mosquitoes and control malaria transmission and may contaminate house dust. House dust is a known medium through which exposure to environmental contaminants occurs, particularly if the contaminants are persistent in the environment. Unlike pyrethroids, DDT is slowly biodegraded and therefore persistent in the environment .n = 216) taken from nonfarmer urban Kenyan mothers up to 4 weeks postpartum also had detectable levels of nine organochlorine pesticides. The most detected organochlorine pesticide in that study was DDT (and its metabolite DDE), although others, such as dieldrin and lindane, were also detected. The ranges of measured concentrations of organochlorine pesticides in breast milk (milk fat basis) were as follows: DDT, 0.002–2.58 mg/kg; DDE, 0.003–4.818 mg/kg; dieldrin, 0.004–0.273 mg/kg; and lindane, 0.002–0.134 mg/kg. Based on intake calculations, p,p′-dichloro diphenyl-dichloroethane (DDD)] and isomer (σ-DDT) in breast milk samples (There is biomonitoring evidence of human exposure to pesticides in Africa. Inhibition of acetylcholinesterase (a biomarker of exposure and effect) has been measured in Kenyan farmworkers who used organophosphates . In anot samples . DDT was samples . CollectVery few health effect studies of farm-worker populations have directly assessed the adverse effects associated with single or multiple pesticide use and exposure among African populations, and no studies have examined the toxicologic consequences of interactions resulting from cumulative exposures to several pesticides in these populations. Most of the available studies on farmworker populations rely on self-reported information to diagnose adverse effects and therefore may not provide the most objective data. Nonetheless, these studies have reported adverse effects such as neurotoxicity associated with organo-phosphate exposure  and birt2) levels  in parts of the city (eight locations) exceeded the 1987 WHO daily hourly average guideline for SO2 (350 μg/m3), with the exception of one site (2 and suspended particulate matter (PM) were both correlated with traffic flow. Other air toxics typically emitted from automobile exhausts include volatile organic compounds and nitrogen oxides. Quantitative data on the impact of automobiles on outdoor air quality are very limited because air quality studies are not routinely conducted for most African cities. However, some of the publicly available and most recent data show a range of air pollution data for PM, SO2, and nitrogen dioxide across different studies and African communities and, more important, highlight pollutant concentration ranges that suggest some communities or populations are exposed to levels of air pollution that exceed recommended limits .Outdoor air pollution in particular has emerged as an issue the last few decades, particularly in Africa’s urban centers because of increased rates of urbanization and industrialization . An impoone site . High le2 annually ]. Highly industrialized regions, such as the eastern Transvaal Highveld region in South Africa, are noted for their high concentration of industries such as petrochemical plants; as of 1990, coal-fired power plants in that region generated 80% of South Africa’s electrical energy ].Indoor air pollution is also an important source of exposure to air toxics in many African homes. A primary source of indoor air pollution is the burning of domestic fuels used in the home . Although traditionally an issue in rural environments, it is an emerging issue in low-income and rapidly urbanizing environments. Other sources of indoor air pollution include pesticides used in the home and cigarette smoking . These emerging environmental challenges to health are occurring within the context of strained health systems . This focused approach has proved effective using the example of the Pb phaseout activities of the PCFV. Moving forward, however, what should prove even more effective in terms of reducing the impact of MEHHs on the health of African populations are environmental health actions and policies that reduce the cumulative burden of MEHHs, because a focus on one MEHH and source at a time provides improvements in overall health status of a population that are eroded by the impacts of MEHHs and sources that remain uncontrolled. As Africa’s environmental health issues become more complex and the continent’s “riskscape” under goes significant change, environmental health policy and action must adopt more comprehensive, holistic, and population-specific approaches for identifying, recognizing, and managing environmental health hazards. Resolving the long-standing issues of traditional hazards in tandem with tackling emerging MEHH issues is necessary to successfully alleviate the burden of avoidable ill health and premature death for all of Africa’s communities.


No mortality or overt signs of toxicity wereobserved during the experiment and the serum activities of transaminases, alkalinephosphatase and cholinesterase were not significantly modified compared to controls. Thehistopathological examination of all the investigated organs: kidney, liver, brain and spleen,revealed significant lesions which were time-dependant and more pronounced in theassociation group. Although the changes were mostly inflammatory and conqestive, it wasproved that the concomitant administration of lithium and hydrochlorothiazid is potentiallydangerous, increasing lithium’s nephrotoxicity and the thiazide diuretic's hepatotoxicity.The biochemical and histological changes following 60 days administration of daily dosesequivalent to 1/20 LD


The effects of vegetable preference and leisure-time physical activity (LPA) on cancer have been inconsistent. We examined the effects of dietary preference and physical activity, as well as their combined effect on cancer risk.This prospective cohort study included 444,963 men, older than 40 years, who participated in a national health examination program begun in 1996. Based on the answer to the question "What kind of dietary preference do you have?" we categorized dietary preference as (1) vegetables, (2) mixture of vegetables and meat, and (3) meats. We categorized LPA as low , moderate , or high . We obtained cancer incidence data for 1996 through 2002 from the Korean Central Cancer Registry. We used a standard Poisson regression model with a log link function and person-time offset to estimate incidence and relative risk..During the 6-year follow-up period, we identified 14,109 cancer cases. Multivariate analysis revealed that a preference for vegetables or a mixture of vegetables and meat as opposed to a preference for meat played a significant protective role against lung cancer incidence . Compared with the low LPA group, subjects with moderate-high LPA had a significantly lower risk for stomach , lung , and liver  cancer. Among current smokers, the combined moderate-high LPA and vegetable or mixture of vegetables and meat preference group showed a 40% reduced risk of lung cancer  compared with the combined low LPA and meat preference group. Among never/former smokers, subjects with moderate-high LPA and a preference for vegetables or a mixture of vegetables and meat showed reduced stomach cancer risk .Our findings add to the evidence of the beneficial effects of vegetable preference on lung cancer risk and of physical activity on lung, stomach, and liver cancer risk. Additionally, vegetable preference combined with LPA might significantly reduce lung and stomach cancer risk. Many studies have investigated the protective effect of vegetable consumption against specific cancers, especially colon,,2 prostaPrevious studies have suggested that PA may have beneficial impact on reducing the sex hormones or insulin resistance and improving immune system, maintaining a healthy body weight by balancing caloric intake with energy expenditure, which could lead to cancer prevention. VegetablRecently, American Cancer Society (ACS) has released the recommendation of PA and nutrition for cancer prevention. Their recommendation is "at least 30 minutes or more of moderate to vigorous activity, above usual activities, on 5 or more days of the week" and "eating five or more serving of vegetables and fruits each day".However, findings of the protective effects of vegetable diet and physical activity on cancer risk from numerous epidemiological studies have been inconsistent,6 and onIn this study we evaluated the effects of dietary preference and PA, as well as their combined effect on cancer incidence in a large, population-based Korean male cohort, adjusting for other known risk factors.The National Health Insurance Corporation (NHIC) has provided biannual health examinations which was obligatory by law to government employees and private school faculty members and their dependants. The study subjects derived to the end of 2002, the National Health Insurance Corporation Study (NHICS) in Korea enrolled 1,216,041  older than 20 years who participated in a national health examination program in 1996. Further study is needed to clarify the association between reported dietary preference and actual food consumed. Fifth, there is a weak scientific evidence for the classification of dietary preferences as (1) meat, (2) vegetable or mixture of vegetables and meat. However, when we performed the analysis with various classifications, we couldn't find significant association between other classification of diet preference and cancer risk. Moreover, one Japanese study also showed that the combined intakes of meat and vegetables on colon cancer incidence.To our knowledge, this is first study for dietary preference and cancer risk. As few is known about the association between dietary preference and cancer risk, further studies are needed. Despite these limitations, our findings add to the evidence of the beneficial effects of vegetable preference on lung cancer risk and of physical activity on lung, stomach, and liver cancer risk. This study suggested that the additive effect of combined vegetable preference and LPA might reduce lung and stomach cancers.LPA: leisure-time physical activity; aRR: adjusted relative risk; PA: physical activity; ACS: American Cancer Society; BMI: body mass index; OPA: occupational physical activity; WHO: World Health Organization; MET: Metabolic Equivalence Task.The authors declare that they have no competing interests.YHY conceived of the study and participated in designing it, analyzing and interpreting the data, and drafting the manuscript. SMP and YJC participated in designing the study, analyzing and interpreting the data, and drafting the manuscript. MKL and YJW participated in designing the study, collecting, assembling, and analyzing the data, and drafting the manuscript. SAS participated in designing the study, collecting and assembling the data, and drafting the manuscript. SWO participated in designing the study and drafting the manuscript. All authors read and approved the final manuscript.The pre-publication history for this paper can be accessed here:


We evaluated total plasma fatty acid concentrations and percentages, and the fatty acid profiles for the different plasma lipid fractions and red blood cell lipids, in 17 patients with untreated colorectal cancer and 12 age-matched controls with no malignant diseases, from the same geographical area. Cancer patients had significantly lower total plasma concentrations of saturated, monounsaturated and essential fatty acids and their polyunsaturated derivatives than healthy controls; when the values were expressed as relative percentages, cancer patients had significantly higher proportions of oleic acid and lower levels of linoleic acid than controls. With regard to lipid fractions, cancer patients had higher proportions of oleic acid in plasma phospholipids, triglycerides and cholesterol esters, and lower percentages of linoleic acid and its derivatives. On the other hand, alpha-linolenic acid was significantly lower in triglycerides from cancer patients and tended to be lower in phospholipids. Its derivatives also tended to be lower in phospholipids and triglycerides from cancer patients. Our findings suggest that colorectal cancer patients present abnormalities in plasma and red blood cell fatty acid profiles characterized by lower amounts of most saturated, monounsaturated and essential fatty acids and their polyunsaturated derivatives, especially members of the n-6 series, than their healthy age-matched counterparts. These changes are probably due to metabolic changes caused by the illness per se but not to malnutrition.


In a cohort study of 49 654 Canadian women, we assessed the association of colorectal cancer with total iron and heme iron intake, excluding iron supplements. Among women aged 40–59 years, followed for an average of 16.4 years, we identified 617 incident colorectal cancer cases. Data from a food frequency questionnaire administered at baseline were used to calculate red meat intake and intake of total dietary iron, iron from meat, and heme iron. Analyses were carried out for all cases and for the proximal colon, distal colon, and rectum, using Cox proportional hazards models. We found no association of intake of iron, heme iron, or iron from meat with risk of colorectal cancer overall or with any of the subsites, nor was there effect modification by alcohol consumption or hormonal replacement therapy. Free iron is a pro-oxidant, and may contribute to colorectal carcinogenesis by promoting free radical production and lipid peroxidation . Epidemi−2 or who were missing information on BMI.Our investigation was conducted in the Canadian National Breast Screening Study (NBSS), a randomised controlled trial of screening for breast cancer, which has been described in detail elsewhere , or death, whichever occurred first. During an average of 16.4 years (786 588 person-years) of follow-up of the dietary cohort, we identified 617 incident colorectal cancer cases.Data from the FFQ were used to calculate total dietary iron intake using a database described elsewhere . In addi−2) (quintiles); menopausal status ; oral contraceptive use (ever/never); hormone replacement use (ever/never); dietary intakes of fat, fiber, folic acid, total calories ; pack-years of smoking (never+five levels); alcohol intake ; education (three levels); physical activity . Addition of indicator variables for screening centre (1–15) and randomisation group in the original clinical trial  did not affect the risk estimates, and therefore these variables were omitted. Because an effect of iron or heme iron intake could be confounded by intake of other dietary constituents with which they are correlated, we included important food items  in additional models. Inclusion of these variables did not affect the risk estimates for iron or heme iron, and as a result they are not included in the final models. We analysed the association of iron-related variables with colorectal cancer overall and with cancers of the colon, proximal colon, distal colon, and rectum. To test for trends in risk with increasing levels of the exposures of interest, we assigned the median value for each quintile and then fitted the medians as a continuous variable in the risk models. We then evaluated the statistical significance of the corresponding coefficient using the Wald test  were used to estimate hazard ratios (HR) and 95% confidence intervals (CI) for the association between iron intake and colorectal cancer risk. Quintiles of iron-related variables were derived based on their distribution in the total population. All multivariate models included the following covariates: age (time to event variable); BMI  and hormone replacement therapy (HRT) use (ever/never). Tests for interaction were based on the likelihood ratio tests comparing models with and without the product terms representing the variables of interest. All statistical significance tests were two-sided. All analyses were performed using SAS version 9 .We further examined the association of the iron-related variables with colorectal cancer risk within strata of potential effect modifiers: alcohol consumption  but not with risk of colon cancer or all colorectal cancer. No associations or trends were seen when iron-related variables were treated as continuous variables (data not shown). The same variables also showed no associations with cancer of the proximal colon (218 cases) or distal colon (164 cases) (data not shown). When cases diagnosed during the first 3 years of follow-up were excluded from the analysis of colorectal cancer, the results were unchanged.In multivariate models adjusting for potential confounding variables, quintiles of total iron intake, heme iron intake, and iron intake from meat showed no association with colon cancer, rectal, or colorectal cancer . Intake r=0.49, P<0.0001), raw vegetables , red meat , and intake of all meats . Intake of heme iron was inversely correlated with vegetable intake (r=−0.06) and positively correlated with intakes of red meat  and all meats . However, these foods were not associated with colorectal cancer risk, and their inclusion in the models did not alter the risk estimates for iron and heme iron.Total dietary iron intake was significantly correlated with intake of vegetables  from all types of meat, whereas Balder et al used differing proportions for different types of meat. We found no association using either method for calculation of heme iron.Three previous studies that have assessed the association between heme iron intake and colon or colorectal cancer have yielded mixed results. In the Iowa Women's Health Cohort, P for trend=0.04).Several other studies have examined intake of iron, either from the diet alone or from both diet and supplements, and markers of body iron stores in relation to colorectal cancer risk. In a Finnish cohort study, Our study has a number of strengths. The large sample size made it possible to examine subsites within the colorectum. Follow-up of the population is virtually complete. We used two different approaches to estimating heme iron intake, with similar results, and we considered a variety of potential confounding variables as well as possible effect modification due to alcohol consumption and hormone replacement use. However, a number of limitations should also be pointed out. No information was available for iron derived from nutritional supplements, which, in a cohort study from New York (In summary, in this large prospective cohort study, we found no suggestion of an association of iron or heme iron intake assessed at baseline with risk of subsequent colorectal cancer or with risk of cancer at subsites within the colorectum. Furthermore, there was no evidence of effect modification by alcohol consumption or hormone replacement use. To determine whether iron intake contributes to the development of colorectal cancer, future studies should improve on the assessment of iron intake by using repeat measurements and obtaining information on use of iron-containing supplements.


Because of evidence of human and environmental risks from exposure to some of these chemicals, the Environmental Protection Agency in the 1970s banned the use of two—the pesticide DDT and a class of industrial chemicals known as polychlorinated biphenyls (PCBs). Despite the ban of more than 30 years, residues of these persistent, bioaccumulative chemicals are still found in human tissue. Now researchers have found evidence of an association between poor attention skills in early infancy and low-level prenatal exposure to PCBs and Previous studies have shown associations between PCB exposure and attention deficits in adults and school-age children. In the current study, the authors sought to investigate whether these associations could be detected in early infancy using the Neonatal Behavioral Assessment Scale (NBAS) to assess infants’ visual and auditory stimuli responses, motor tone and motor activity levels, and ability to regulate crying, alert, and sleep states. These behavioral items identify the infant’s capacity for attention as well as abilities potentially associated with attention, such as state regulation and motor maturity.The present study included infants born between 1993 and 1998 to mothers who lived near a PCB-contaminated harbor in New Bedford, Massachusetts. The NBAS was administered to infants twice: between 1 and 3 days after birth and between 5 and 22 days after birth. The researchers also administered questionnaires to mothers of the infants to collect demographic data on household income; medical and reproductive histories; drug, alcohol, and tobacco use; race and ethnicity; and occupational and exposure histories pertinent to outcomes of interest.p,p′-DDE. Of the total serum samples, 96% had detectable DDE levels; depending on the PCB congener, anywhere from fewer than 1% to 91% of the infants had detectable serum levels. For the 542 infants that completed both exams, statistical analysis revealed a decline in scores of attention with increased serum levels of DDE and of PCBs. The exposure-associated declines were less pronounced for abilities associated with attention, including state- and motor-associated outcomes.To determine OC levels in the infants, the researchers analyzed infant cord serum samples, taken at birth, for 51 PCB congeners and The authors acknowledge the uncertainty of the NBAS in accurately predicting attention behaviors that may occur later in childhood. Future studies should examine whether the attention deficits observed in the current study in association with organochlorine exposure persist into childhood.


Leukaemic cells taken from the blood of patients with acute myelogenous leukaemia (AML) frequently proliferate in suspension culture without the addition of growth factors for a limited period only. After a 6--10-fold increase in total cells, cell numbers remain constant for a time and finally decline. The main cause for this limited growth in vitro is not, initially at least, cell death leading to a steady state, but maturation associated in its final stages with cessation of DNA synthesis. Two populations of AML cells from Patients St and Wi respectively were studied, and progressive maturation towards mature leucocytes was demonstrated by the gradual acquisition in culture by the growing blast cells of intracellular enzymes , surface markers (Fc and C3 receptors), of lactoferrin by Wi cells and of colony-stimulating activity by St cells, as well as changes in Ia antigens, phagocytic properties, morphology and adhesiveness to plastic. With St cells, which carried a characteristic chromosome marker, maturation terminated in cells with the characteristic properties of macrophages. At an intermediate stage, non-adherent and still-dividing St cells acquired Fc and C3 receptors and enzymes characteristic of monocytes. Wi cells progressively became neutrophil-like, and again there was an intermediate population of dividing cells which had Fc and C3 receptors and proteins such as lactoferrin and esterases. characteristic of neutrophils.


Research programs within medical and dental schools are important vehicles for biomedical and clinical discovery, serving as effective teaching and learning tools by providing situations in which predoctoral students develop problem-solving and critical-thinking skills. Although research programs at many medical and dental schools are well-established, they may not be well integrated into the predoctoral curriculum to effectively support the learning objectives for their students.A series of structured seminars, incorporating faculty research, was designed for first-year dental students at the University of Nevada, Las Vegas, School of Dental Medicine to reinforce and support the concepts and skills taught in concurrent courses. A structured research enrichment period was also created to facilitate student engagement in active research using faculty and student curricular release time. Course evaluations and surveys were administered to gauge student perceptions of the curricular integration of research, the impact of these seminars on recruitment to the research program, and overall levels of student satisfaction with research enrichment.The analysis of course surveys revealed that students perceived the research-containing seminars effectively illustrated concepts, were logically sequenced, and were well-integrated into their curriculum. In addition, analysis of surveys revealed that the Integration Seminar courses motivated students to engage in research enrichment. Finally, this analysis provided evidence that students were very satisfied with their overall learning experience during research enrichment.Curricular integration is one method of improving the teaching and learning of complicated and inter-related concepts, providing an opportunity to incorporate research training and objectives into traditionally separate didactic courses. Despite the benefits of curricular integration, finding the most appropriate points of integration, obtaining release time for curricular development and for research engagement, and funding predoctoral student research remain issues to be addressed in ways that reflect the character of the faculty and the goals of each institution. Research is an important component of many predoctoral medical and dental education programs focused on training students as clinicians, educators, and researchers in evidence-based practices -3. BiomeOne key to implementing effective research programs is the degree to which they can be successfully integrated into the curriculum. Medical and dental educators increasingly recognize that the traditional approach to teaching biomedical concepts and clinical training often lack both cohesiveness and an emphasis on research training and education ,3,5. To The expectation is that horizontal and vertical integration will result in a better understanding of important biomedical principles, improved retention of knowledge, and an enhanced ability for students to apply biomedical concepts in clinically appropriate settings ,11. One Marquette was one of the first dental schools to restructure its curriculum to incorporate a research emphasis. This research emphasis fosters appreciation of biomedical and clinical research and discovery through dedicated didactic time devoted to mentored scholarly research from various disciplines . This cuThe University of Nevada, Las Vegas, School of Dental Medicine (UNLV-SDM) has similarly defined its primary education goal as the implementation of "a vertical and horizontal integration of the Biomedical Sciences, Professional Studies, and Clinical Sciences curricula to ensure competent, contemporary oral healthcare providers" . The UNLThis report describes the development and structure of the integrated research program at the UNLV-SDM, as well as internal evaluation measures and plans for future development of the program. In brief, participating research faculty first coordinated and presented research seminars in a first-year course, the Integration Seminar . These rOur assessment suggests the research enrichment program was both vertically and horizontally integrated into the curriculum at the UNLV-SDM. Course evaluations of the Integration Seminar demonstrated that first-year dental students overwhelmingly recognized that the research presentations were integrated and logically sequenced. Furthermore, an internal assessment of pre- and post-research enrichment surveys demonstrated that students were satisfied with their research enrichment experience.While the UNLV-SDM structured a predoctoral curriculum integrating the majority of courses, a first-year, two-semester course was designed and implemented to further facilitate both horizontal and vertical integration of basic and clinical sciences. Each first-year cohort of 75 dental students (DS1) takes two semesters of the Integration Seminar course, during the Fall and Spring semesters, receiving one credit per semester, graded on a Pass/Fail system determined by student participation and attendance. Course directors from integrated DS1 courses develop topics for each semester of the Integration Seminar, examining a central theme, issue, or contemporary health care problem that parallels and strengthens the course concepts addressed in concurrent DS1 courses .In addition to the standard predoctoral curriculum at UNLV-SDM, students may participate in Research Enrichment, a voluntary elective with a research emphasis. Research Enrichment is a period of curricular release time, between the DS1 Spring and Summer semesters, when students may pursue scholarly activities with a designated mentor. Selected research faculty are given protected time to plan, administer, teach, mentor, and evaluate structured research training for interested DS1 students.More specifically, the basic format for each research enrichment period involves approximately one month of dedicated curriculum release time for the dental students and designated research faculty. Guidelines, goals, and expectations for performing research are distributed by the Associate Dean for Research prior to the beginning of this period and students are matched with an appropriate mentor based upon a combination of scientific interest and experience. The first week of this period involves general orientations, mandatory UNLV Environmental Health and Safety training, and specialized Biosafety Level-2 (BSL-2) training. The remaining weeks are spent developing and performing hypothesis-driven experiments, documenting research results, and subsequently analyzing these results for dissemination via publication or meeting presentation.DS1 course instructors who provide evidence of integrated course materials and instruction between two or more departments or disciplines are selected to participate in the Integration Seminar. Participating faculty selected the concepts and topics for these seminars, including topics that integrated current, applied research under their direction. The pool of faculty for the years evaluated for this report included all faculty from Biomedical Sciences (7), Professional Studies (5) and Clinical Sciences  departments, as well as other UNLV and external and student speakers.Potential faculty mentors designed and presented seminars within the Integration Seminar course, incorporating their clinical, professional, or behavioral sciences-related research. Their research was directly correlated with the learning objectives for the seminar, and was presented to initiate and facilitate interactive discussions with students regarding relationships and concepts that pertained to concurrent DS1 course offerings, thus fostering horizontal integration. These seminars familiarized all DS1 students with faculty-directed research projects and served as a potential point of recruitment for interested students. Seminars with content demonstrating the integration of faculty research into the seminar objectives were then tallied and reported.We collected qualitative course evaluation data over a three-year period, using the UNLV-SDM mandated, anonymous survey that was administered to each cohort C1, C2, C3) of students at the end of each Integration Seminar course (N = 225)  environmental health and safety training, ii) specialized BSL-2 laboratory safety training, iii) individualized, hands-on mentoring in cell and molecular biology techniques, iv) training in the use of online literature databases, v) critical analysis and evaluation of peer-reviewed primary research articles, vi) statistical training specific to bias, confounding, study design, and hypothesis testing, vii) documentation of results, and viii) writing and editing of manuscripts for publication and abstracts for local or national meetings.Upon completion of the research enrichment, it is expected that dental students are able to do each of the following:• Understand and adhere to basic and advanced biomedical laboratory research safety protocols and standards;• Understand and perform online literature searches and database utilization for biomedical and clinical research;• Understand and discuss the protocols, limitations, and results of peer-reviewed biomedical and clinical research manuscripts;• Design, execute, and evaluate research protocols using hypothesis testing;• Accurately and descriptively summarize results for dissemination to biomedical and clinical researchers in abstract or manuscript form.We collected qualitative evaluation data using an anonymous survey that was administered to students at the end of each research enrichment period and collected by an administrative assistant N = 13)  from 225 students in the three most recent UNLV-SDM cohorts were retrieved and provided in non-identifiable, summarized format by the Office of Student Affairs to prevent the disclosure, and ensure the confidentiality, of any potential personally identifiable private information.Our protocol was approved by the Institutional Research Board (IRB), as an exemption to human subjects research under the Basic HHS Policy for Protection of Human Research Subjects, (46.101) Subpart A (b) regarding IRB Exemption for 1) research conducted in established educational settings involving normal educational practices, where the subjects cannot be identified or linked, directly or through identifiers.In the first year (C1), 15 faculty members and speakers  created 20 seminars over the two semesters for the Integration Seminar, of which 2 seminars, or 10%, specifically integrated research . In the second year (C2), 18 faculty members and speakers  created 20 seminars for the Integration Seminar series, of which 9 seminars, or 45%, specifically integrated research . In the third year (C3), 22 faculty members and speakers  created 22 seminars for these courses, of which 16, or 73%, specifically integrated research .The UNLV-SDM course evaluation was administered to each student cohort (75 students per cohort) at the end of both Fall and Spring semesters. The response rate among the three cohorts ranged from 78 to 80% . Data were provided in non-identifiable, summarized format by the Office of Student Affairs, revealing only the response rate and percent of responses for each question. Analysis of qualitative course evaluation survey data revealed that the vast majority of students asserted that the components of this course were coherently sequenced, that cogent examples were used within the course, and that these components were well integrated into the curriculum Figure . Fewer tMore specifically, student responses to the first evaluated survey question, "The learning plan was smooth, sequenced, and logical", revealed that a significant proportion of students had positive perceptions regarding the sequence and logical order of the course components, which included the research presentations Figure . Almost Student responses to the second evaluated survey question, "Examples and illustrations were effective", revealed that the overwhelming majority of students in each cohort had positive perceptions of the horizontally integrated clinical and research examples used in this course Figure . VirtualStudent responses to the third evaluated survey question, "This course is integrated into the curriculum and not redundant", once again demonstrated that most student from each cohort had positive perceptions of the horizontal integration of this course and the seminar material into the curriculum Figure . Nearly In the first year C1), 2 students participated in research enrichment. In the second year (C2), the number of students participating in research enrichment tripled to 6, and in the third year (C3), 5 students engaged in research enrichment. Seventy-seven percent (10/13) of dental students who participated in research enrichment from all three cohorts  completed the recruitment survey  completed the environmental health and safety training, BSL-2 laboratory safety training, individual, hands-on mentoring in cell culture and molecular biology techniques, as well as training in the use of online literature databases. Furthermore, these students were allowed the opportunity to expand and develop their statistical competence and critical analysis and writing skills, as evidenced by their recent publication successes. Both students from the initial cohort (C1) have successfully co-authored manuscripts ,20, as dThe qualitative evaluation survey for the enrichment period was administered to all three cohorts of dental students who volunteered for the research enrichment period Table . AnalysiMore specifically, 75% of these students "strongly agree" that enrichment period was intellectually stimulating (Question 1) and were satisfied with their overall educational experience during the research enrichment period (Question 2). All students "strongly agree" that if they had it to do over again, they would enroll in this research enrichment period (Question 3). Furthermore, all students indicated that other dental students would benefit from participation in this program (Question 4), while 88% "strongly agree" that they would recommend the research enrichment period to others (Question 5).In addition, several students volunteered to present their research data and results in the Integration Seminar during the following year and were counted as external/other speakers. Half of the participants from the first cohort, C1, presented to the following cohort, C2, as part of the Integration Seminar course and three-fourths of the second cohort, C2, presented their research results and data in the Integration Seminar course during the subsequent academic year. The most recent cohort, C3, will have the opportunity to present their research in the Integration Seminar course to the incoming cohort, C4, during the 2007–2008 academic year. Furthermore, a more detailed analysis of the survey data regarding the influence of the Integration Seminar to motivate dental students to perform research revealed that 80% of respondents had positive responses ("strongly agree" or "agree") to the statement that dental student presentations influenced their decision to enroll in the research enrichment period  and the number of students recruited. More specifically, although greater than 80% of students cited the Integration Seminar as a motivational influence on their decision to participate in research enrichment, twice as many students "strongly agree" that they were more influenced by the presentation of previous student researcher participants than by faculty presentations Table . FinallyAlthough this report describes the design and implementation of a research enrichment program for predoctoral dental students and the process and mechanism for integrating this research into components of the dental school curriculum, there are several limitations of this study. First, and most importantly, UNLV-SDM is a new program and has the benefits and problems associated with recently established schools. As a benefit, the curriculum and many of the faculty are new and were specifically recruited for their willingness to implement new curricular innovations, such as integration. Two challenges have been the limited number of faculty with established research programs and the limited amount of funds available for new, tenure-track faculty to support student research. Despite the limitations and challenges, the results of this report may be of value to other dental, medical, or professional schools with a similar goal of incorporating research and achieving curriculum integration.Medical and dental education curricula are continually developing by incorporating advancements, such as horizontal and vertical integration, to address the contemporary needs of their students. This study provides an example of how current research by faculty and predoctoral students can be incorporated in an organized and structured manner into the curriculum. In addition, several areas of future research and potential improvement were identified during the process of analyzing these data, which will be the subject of future studies. First is the separation of the Integration Seminar series into two courses, one as an introductory biomedical, professional, and clinical integration seminar series and the second as an applied, research-specific integration series focused primarily on student research and participation, and more specifically on dissemination of their results to incoming dental school cohorts. The second is evaluating the relative benefits of research participation on recruitment of future faculty members and in the selection of post-graduate specialty training.The author(s) declare that they have no competing interests.KK was responsible for design of the concept and for integrating research enrichment into the Integration Seminar courses. KK, SO, and KH developed the research enrichment goals and objectives and directed the research enrichment. SO and TS developed and coordinated the survey methods, data collection, and data analysis. All authors have read and approved the final version of this manuscript.The pre-publication history for this paper can be accessed here:UNLV-SDM course evaluation. Anonymous survey administered to students at the completion of each Integration Seminar course.Click here for fileUNLV-SDM Enrichment Period recruitment survey. Anonymous student survey designed to identify the factors that most impacted their decision to participate in research enrichment.Click here for fileUNLV-SDM Post-Enrichment Period survey instrument. Anonymous surveys designed to gauge students' opinions of their research experience during the enrichment period.Click here for file