Toxic effects of mercury, lead and gadolinium on vascular reactivity

Heavy metals have been used in a wide variety of human activities that have significantly increased both professional and environmental exposure. Unfortunately, disasters have highlighted the toxic effects of metals on different organs and systems. Over the last 50 years, the adverse effects of chronic lead, mercury and gadolinium exposure have been underscored. Mercury and lead induce hypertension in humans and animals, affecting endothelial function in addition to their other effects. Increased cardiovascular risk after exposure to metals has been reported, but the underlying mechanisms, mainly for short periods of time and at low concentrations, have not been well explored. The presence of other metals such as gadolinium has raised concerns about contrast-induced nephropathy and, interestingly, despite this negative action, gadolinium has not been defined as a toxic agent. The main actions of these metals, demonstrated in animal and human studies, are an increase of free radical production and oxidative stress and stimulation of angiotensin I-converting enzyme activity, among others. Increased vascular reactivity, highlighted in the present review, resulting from these actions might be an important mechanism underlying increased cardiovascular risk. Finally, the results described in this review suggest that mercury, lead and gadolinium, even at low doses or concentrations, affect vascular reactivity. Acting via the endothelium, by continuous exposure followed by their absorption, they can increase the production of free radicals and of angiotensin II, representing a hazard for cardiovascular function. In addition, the actual reference values, considered to pose no risk, need to be reduced.

Risk perception about zoonoses in immigrants and Italian workers in Northwestern Italy

OBJETIVO: To assess factors associated with a low risk perception of zoonoses and to identify the gaps in knowledge about transmission and prevention of zoonoses in immigrant and Italian workers. MÉTODOS: A cross-sectional study with 175 workers in the agro-livestock and agro-food industry in Piemonte, Italy, was carried out. Data were collected with a semi-structured questionnaire based on knowledge, attitudes and practices (KAP) survey. We calculated proportions and used chi-square tests and odds ratios to assess associations. Eight individual interviews with key informants on immigration and public health in Piemonte were carried out. RESULTADOS: Participants were 82 (47%) Italians and 93 (53%) immigrants. Immigrants were from Romania, Morocco, Albania, India, China, Argentina, Peru, Macedonia, Ivory Coast, Ukraine and Colombia. The study revealed significant differences in risk perception at work (p = 0.001). We found associations between "not having correct knowledge about zoonoses" and the following variables: i. "being immigrant" OR = 4.1 (95%CI 1.7;9.8 p ≤ 0.01); ii. "working in the livestock industry" OR = 2.9 (95%CI 1.2;15.4 p = 0.01); and iii. "being an unqualified worker" OR = 4.4 (95%CI 2.9;15.4 p ≤ 0.01). Another strong association was found between being immigrant and having a low job qualification OR = 6.7 (IC95% 2.9 - 15.4 p ≤ 0.01). Asian immigrants were the group with the highest frequency of risky behaviours and the lowest level of knowledge about zoonoses. CONCLUSÕES: Our results indicate that there were differences in risk perception of zoonoses between the groups participating in our study. These results suggest that immigrant status can be considered a risk factor for having lower risk perception and lower level of knowledge of zoonoses at work. There is a relationship between this specific knowledge of zoonoses and lack of training and instruction among migrant populations. Our results stress the need for developing education programs on zoonoses prevention among the immigrant population in Piemonte, Italy.

Human risk assessment of benzene after a gasoline station fuel leak

OBJECTIVE: To assess the health risk of exposure to benzene for a community affected by a fuel leak. METHODS: Data regarding the fuel leak accident with, which occurred in the Brasilia, Federal District, were obtained from the Fuel Distributor reports provided to the environmental authority. Information about the affected population (22 individuals) was obtained from focal groups of eight individuals. Length of exposure and water benzene concentration were estimated through a groundwater flow model associated with a benzene propagation model. The risk assessment was conducted according to the Agency for Toxic Substances and Disease Registry methodology. RESULTS: A high risk perception related to the health consequences of the accident was evident in the affected community (22 individuals), probably due to the lack of assistance and a poor risk communication from government authorities and the polluting agent. The community had been exposed to unsafe levels of benzene (> 5 µg/L) since December 2001, five months before they reported the leak. The mean benzene level in drinking water (72.2 µg/L) was higher than that obtained by the Fuel Distributer using the Risk Based Corrective Action methodology (17.2 µg/L).The estimated benzene intake from the consumption of water and food reached a maximum of 0.0091 µg/kg bw/day (5 x 10-7 cancer risk per 106 individuals). The level of benzene in water vapor while showering reached 7.5 µg/m3 for children (1 per 104 cancer risk). Total cancer risk ranged from 110 to 200 per 106 individuals. CONCLUSIONS: The population affected by the fuel leak was exposed to benzene levels that might have represented a health risk. Local government authorities need to develop better strategies to respond rapidly to these types of accidents to protect the health of the affected population and the environment.

Incidence and risk factors for intimate partner violence during the postpartum period

OBJECTIVE To estimate the incidence and identify risk factors for intimate partner violence during postpartum.METHODS This prospective cohort study was conducted with women, aged between 18-49 years, enrolled in the Brazilian Family Health Strategy in Recife, Northeastern Brazil, between 2005 and 2006. Of the 1.057 women interviewed during pregnancy and postpartum, 539 women, who did not report violence before or during pregnancy, were evaluated. A theoretical-conceptual framework was built with three levels of factors hierarchically ordered: women’s and partners’ sociodemografic and behavioral characteristics, and relationship dynamics. Incidence and risk factors of intimate partner violence were estimated by Poisson Regression.RESULTS The incidence of violence during postpartum was 9.3% (95%CI 7.0;12.0). Isolated psychological violence was the most common (4.3%; 95%CI 2.8;6.4). The overlapping of psychological with physical violence occurred at 3.3% (95%CI 2.0;5.3) and with physical and/or sexual in almost 2.0% (95%CI 0.8;3.0) of cases. The risk of partner violence during postpartum was increased for women with a low level of education (RR = 2.6; 95%CI 1.3;5.4), without own income (RR = 1.7; 95%CI 1.0;2.9) and those who perpetrated physical violence against their partner without being assaulted first (RR = 2.0; 95%CI 1.2;3.4), had a very controlling partner (RR = 2.5; 95%CI 1.1;5.8), and had frequent fights with their partner (RR = 1.7; 95%CI 1.0;2.9).CONCLUSIONS The high incidence of intimate partner violence during postpartum and its association with aspects of the relationship’s quality between the couple, demonstrated the need for public policies that promote conflict mediation and enable forms of empowerment for women to address the cycle of violence.

Occupational conditions and the risk of the use of amphetamines by truck drivers

OBJECTIVE To test whether the occupational conditions of professional truck drivers are associated with amphetamine use after demographic characteristics and ones regarding mental health and drug use are controlled for.METHODS Cross-sectional study, with a non-probabilistic sample of 684 male truck drivers, which was collected in three highways in Sao Paulo between years 2012 and 2013. Demographic and occupational information was collected, as well as data on drug use and mental health (sleep quality, emotional stress, and psychiatric disorders). A logistic regression model was developed to identify factors associated with amphetamine use. Odds ratio (OR; 95%CI) was defined as the measure for association. The significance level was established as p < 0.05.RESULTS The studied sample was found to have an average age of 36.7 (SD = 7.8) years, as well as low education (8.6 [SD = 2.3] years); 29.0% of drivers reported having used amphetamines within the twelve months prior to their interviews. After demographic and occupational variables had been controlled for, the factors which indicated amphetamine use among truck drivers were the following: being younger than 38 years (OR = 3.69), having spent less than nine years at school (OR = 1.76), being autonomous (OR = 1.65), working night shifts or irregular schedules (OR = 2.05), working over 12 hours daily (OR = 2.14), and drinking alcohol (OR = 1.74).CONCLUSIONS Occupational aspects are closely related to amphetamine use among truck drivers, which reinforces the importance of closely following the application of law (Resting Act (“Lei do Descanso”); Law 12,619/2012) which regulates the workload and hours of those professionals. Our results show the need for increased strictness on the trade and prescription of amphetamines in Brazil.

Chikungunya risk for Brazil

This study aimed to show, based on the literature on the subject, the potential for dispersal and establishment of the chikungunya virus in Brazil. The chikungunya virus, a Togaviridae member of the genusAlphavirus, reached the Americas in 2013 and, the following year, more than a million cases were reported. In Brazil, indigenous transmission was registered in Amapa and Bahia States, even during the period of low rainfall, exposing the whole country to the risk of virus spreading. Brazil is historically infested by Ae. aegypti and Ae. albopictus, also dengue vectors. Chikungunya may spread, and it is important to take measures to prevent the virus from becoming endemic in the country. Adequate care for patients with chikungunya fever requires training general practitioners, rheumatologists, nurses, and experts in laboratory diagnosis. Up to November 2014, more than 1,000 cases of the virus were reported in Brazil. There is a need for experimental studies in animal models to understand the dynamics of infection and the pathogenesis as well as to identify pathophysiological mechanisms that may contribute to identifying effective drugs against the virus. Clinical trials are needed to identify the causal relationship between the virus and serious injuries observed in different organs and joints. In the absence of vaccines or effective drugs against the virus, currently the only way to prevent the disease is vector control, which will also reduce the number of cases of dengue fever.

Identification of factors and groups at risk of infection with Schistosoma mansoni: a strategy for the implementation of control measures?

A fourteen year schistosomiasis control program in Peri-Peri (Capim Branco, MG) reduced prevalence from 43.5 to 4.4%; incidence from 19.0 to 2.9%, the geometric mean of the number of eggs from 281 to 87 and the level of the hepatoesplenic form cases from 5.9 to 0.0%. In 1991, three years after the interruption of the program, the prevalence had risen to 19.6%. The district consists of Barbosa (a rural area) and Peri-Peri itself (an urban area). In 1991, the prevalence in the two areas was 28.4% and 16.0% respectively. A multivariate analysis of risk factors for schistosomiasis indicated the domestic agricultural activity with population attributive risk (PAR) of 29.82%, the distance (< 10 m) from home to water source (PAR = 25.93%) and weekly fishing (PAR = 17.21%) as being responsible for infections in the rural area. The recommended control measures for this area are non-manual irrigation and removal of homes to more than ten meters from irrigation ditches. In the urban area, it was observed that swimming at weekly intervals (PAR = 20.71%), daily domestic agricultural activity (PAR = 4.07%) and the absence of drinking water in the home (PAR=4.29%) were responsible for infections. Thus, in the urban area the recommended control measures are the substitution of manual irrigation with an irrigation method that avoids contact with water, the creation of leisure options of the population and the provision of a domestic water supply. The authors call attention to the need for the efficacy of multivariate analysis of risk factors to be evaluated for schistosomiasis prior to its large scale use as a indicator of the control measures to be implemented.

Frequency of human bocavirus respiratory infections among at-risk patients in São Paulo, Brazil

BACKGROUND AND OBJECTIVES: Human Bocavirus (HBoV) has been described since 2005 as an etiological agent of respiratory virus infections. From 2001 to 2008 we investigated the etiology of HBoV among adults and children in different groups at risk of presenting complications arising from acute respiratory infection, the investigation was carried out in a tertiary hospital health care system in Brazil. METHODS: HBoV DNA was assayed in 598 respiratory samples from community and hospitalized patients by PCR. RESULTS: Of the 598 tested samples, 2.44% (8/328) of children, including five children with heart disease, and 0.4% (1/270) of adult bone-marrow-transplant were HBoV positive. CONCLUSIONS: These data suggested lower HBoV frequency among different at-risk patients and highlights the need to better understand the real role of HBoV among acute respiratory symptomatic patients.

Risk factors associated with hantavirosis fatality: a regional analysis from a case-control study in Brazil

Introduction: In Brazil, hantavirus cardiopulmonary syndrome (HCPS) has a high lethality rate that varies by region. This study aimed to identify the risk factors associated with fatal hantavirosis. Methods: This study was a case-control study that included all laboratory confirmed cases of hantavirosis. The cases were stratified by the different Brazilian regions using data from the Notifiable Diseases Information System. “Cases” were patients who progressed to death, whereas “controls” were patients who were cured. The odds ratio (OR) and the adjusted OR were calculated. Results: Overall, 158 cases and 281 controls were included in this study. In the Midwest region, the cases were 60% less likely to present with flank pain, and the time between the beginning of symptoms and death was shorter than the time between the beginning of symptoms and a cure. In the Southeast region, the cases were 60% less likely to present with thrombocytopenia or reside in rural areas compared to those who progressed to a cure. Additionally, the cases sought medical assistance, notification and investigation more quickly than the controls. In the Southern region, the cases that died were 70% less likely to be male compared to the controls. Conclusions: HCPS manifests with nonspecific symptoms, and there are few published studies related to the condition, so determining a patient's therapeutic strategy is difficult. This study presents findings from different Brazilian regions and highlights the need for further investigations to improve comprehension about regional risk factors associated with hantavirosis and to reduce morbimortality.

The prevalence of hepatitis B virus infection markers and socio-demographic risk factors in HIV-infected patients in Southern Brazil

IntroductionHepatitis B virus (HBV) and human immunodeficiency virus (HIV) infections are two of the world's most important infectious diseases. Our objective was to determine the hepatitis B surface antigen (HBsAg) and hepatitis B core antibody (anti-HBc) prevalences among adult HIV-infected patients and identify the associations between socio-demographic variables and these HBV infection markers.MethodsThis study was performed from October 2012 to March 2013. Three hundred HIV-seropositive patients were monitored by the Clinical Analysis Laboratory of Professor Polydoro Ernani de São Thiago University Hospital, Santa Catarina, Brazil. The blood tests included HBsAg, anti-HBc immunoglobulin M (IgM) and total anti-HBc. Patients reported their HIV viral loads and CD4+ T-cell counts using a questionnaire designed to collect sociodemographic data.ResultsThe mean patient age was 44.6 years, the mean CD4 T-cell count was 525/mm3, the mean time since beginning antiretroviral therapy was 7.6 years, and the mean time since HIV diagnosis was 9.6 years. The overall prevalences of HBsAg and total anti-HBc were 2.3% and 29.3%, respectively. Among the individuals analyzed, 0.3% were positive for HBsAg, 27.3% were positive for total anti-HBc, and 2.0% were positive either for HBsAg or total anti-HBc and were classified as chronically HBV-infected. Furthermore, 70.3% of the patients were classified as never having been infected. Male gender, age >40 years and Caucasian ethnicity were associated with an anti-HBc positive test.ConclusionsThe results showed an intermediate prevalence of HBsAg among the studied patients. Moreover, the associations between the anti-HBc marker and socio-demographic factors suggest a need for HBV immunization among these HIV-positive individuals, who are likely to have HIV/HBV coinfection.

Toxoplasma gondii infection: seroprevalence and associated risk factors among primary schoolchildren in Lagos City, Southern Nigeria

INTRODUCTION: Toxoplasma gondii infection has been described as the most widespread zoonotic infection of humans and other animals. Information concerning T. gondii infection among schoolchildren is unavailable in Lagos City, Nigeria. METHODS: This cross-sectional study investigated the seroprevalence and risk factors associated with T. gondii infection among primary schoolchildren (PSC) from a community located in the center of Lagos, southern Nigeria, from November 2013 to March 2014. A total of 382 PSC were screened for the presence of sera anti-T. gondii antibodies using a latex agglutination test (TOXO Test-MT, Tokyo, Japan). A cutoff titer of ≥ 1:32 was considered positive, while titers ≥ 1:1,024 indicated high responders. Questionnaires were also used to obtain data on possible risk factors from parents/guardians. RESULTS: The overall seroprevalence was 24% (91/382), and 83.5% (76/91) of seropositive PSC were classified as high responders. Among the risk factors tested, including contact with cats and soil, consumption of raw meat and vegetables, and drinking unboiled water, none showed statistical significance after multivariate adjustment. No associations were observed among age, gender, body mass index (BMI), and parents' occupation/educational level. CONCLUSIONS: The findings in this study show evidence of active infection, and hence, there is need for urgent preventive measures in this city. Further investigation is required to clarify the transmission routes. Policy makers also need to initiate prevention and control programs to protect pregnant women and immunocompromised patients in particular because they are more severely affected by T. gondii infection.

Basic sanitation, socioeconomic conditions, and degree of risk for the presence and maintenance of malaria in a low-transmission area in the Brazilian Amazon

ABSTRACTINTRODUCTION:This study aimed to evaluate basic sanitation and socioeconomic indicators, reported cases of malaria, and risk of contracting malaria in the Ananindeua municipality, State of Pará.METHODS:Data on basic sanitation and socioeconomic dimensions were taken from the Brazilian Institute of Geography and Statistics [ Instituto Brasileiro de Geografia e Estatística (IBGE)] 2010 census. Epidemiological malaria information was taken from the Epidemiological Malaria Surveillance Information System [ Sistema de Informação de Vigilância Epidemiológica de Malária (SIVEP/Malaria)], between 2003 and 2013 of the Ministry of Health and from the SIVEP/Malaria forms of the municipality's Endemic Diseases Unit for 2,013 cases.RESULTS:Our data do not confirm the correlation among indicators of basic sanitation, socioeconomic conditions, and water supply with malaria cases. Of the 1,557 cases evaluated, most were caused by Plasmodium vivax , with rare cases of Plasmodium falciparum and mixed infections. There were 756 notifications in 2003. The number of reported cases was sharply reduced between 2006 and 2012, but a 142-case outbreak occurred in 2013. Ananindeua municipality's Annual Parasite Index indicated low risk in 2003 and no risk in other years, and the 2,013 cases were predominantly male individuals aged ≥40 years.CONCLUSIONS:Our data confirm the non-endemicity of malaria in the Ananindeua municipality, as the Annual Parasite Indices described for the years 2004-2013 classify it as a risk-free area. However, the 2013 outbreak indicates the need to strengthen prevention, surveillance, and control activities to reduce the risk of new outbreaks and consequent economic and social impacts on the population.

Why do we need randomized and epidemiological studies on cardiovascular disease? Evidence-based cardiology VII

Over the last two decades the results of randomized clinical studies, which are powerful aids for correctly assessing therapeutical strategies, have consolidated cardiological practice. In addition, scientifically interesting hypotheses have been generated through the results of epidemiological studies. Properly conducted randomized studies without systematic errors and with statistical power adequate for demonstrating moderate and reasonable benefits in relevant clinical outcomes have provided reliable and strong results altering clinical practice, thus providing adequate treatment for patients with cardiovascular disease (CVD). The dissemination and use of evidence-based medicine in treating coronary artery disease (CAD), heart failure (HF), and in prevention will prevent hundreds of thousands of deaths annually in developed and developing countries. CVD is responsible for approximately 12 million deaths annually throughout the world, and approximately 60% of these deaths occur in developing countries. During recent years, an increase in mortality and morbidity rates due to CVD has occurred in developing countries. This increase is an indication that an epidemiological (demographic, economical, and health-related) transition is taking place in developing countries and this transition implies a global epidemic of CVD, which will require wide-ranging and globally effective strategies for prevention. The identification of conventional and emerging risk factors for CVD, as well as their management in high-risk individuals, has contributed to the decrease in the mortality rate due to CVD. Through a national collaboration, several multi-center and multinational randomized and epidemiological studies have been carried out throughout Brazil, thus contributing not only to a generalized scientific growth in different Brazilian hospitals but also to the consolidation of an increasingly evidence-based clinical practice.

Risk factors for atherosclerosis in students of a private university in São Paulo - Brazil

OBJECTIVE: To characterize the risk profile for atherosclerosis (AS) in adolescents and young adults of a private university in São Paulo. METHODS: Clinical, nutritional, and laboratory parameters were evaluated in 209 students of both genders aged 17 to 25 years. In addition to determination of the lipid profile, the association of its abnormal values with other risk factors for AS was also investigated. RESULTS: Increased levels of total cholesterol, LDL-C and triglycerides (TG) were observed in 9.1%, 7.6% and 16.3% of the students, respectively, and decreased levels of HDL-C in 8.6% of them. Prevalence of the remaining risk factors analyzed was elevated: sedentary life style (78.9%); high intake of total fat (77.5%); high cholesterol intake (35.9%); smoking, hypertension (15.8%) and obesity (7.2%). There was an association between elevated LDL-C and TG levels and sedentary life style and body mass index. CONCLUSION: The high prevalence of risk factors for AS in young individuals draws attention to the need for adopting preventive plans.

Hypertension and clustering of cardiovascular risk factors in a community in Southeast Brazil: the Bambuí Health and Ageing Study

OBJECTIVE - A population-based prospective study was analysed to: a) determine the prevalence of hypertension; b) investigate the clustering of other cardiovascular risk factors and c) verify whether older differed from younger adults in the pattern of clustering. METHODS - The data comprised a representative sample of the population of Bambuí, Brazil. Multiple logistic regression was used to investigate the independent association between hypertension and selected factors. RESULTS - A total of 820 younger adults (82.5%) and 1494 older adults (85.9%) participated in this study. The overall prevalence of hypertension was 24.8% (SE=1.4 %), being higher in women (26.9±1.5%) than in men (22.0± 1.7%) (p=0.033). Hypertension was positively and significantly associated with physical inactivity, overweight, hypercholesterolemia hyperglycemia and hypertriglyceridemia. The coexistence of hypertension with 4 or more of these risk factors occurred 6 times more than expected by chance, after adjusting for age and sex (OR=6.3; 95%CI: 3.4-11.9). The pattern of risk factor clustering in hypertensive individuals differed with age. CONCLUSION - Our results reinforce the need to increase detection and treatment of hypertension and to approach patients' global risk profiles.