Solid phase microextraction as a short-term sampling technique for BTEX occupational exposure

Solid phase microextraction (SPME) has been widely used for many years in various applications, such as environmental and water samples, food and fragrance analysis, or biological fluids. The aim of this study was to suggest the SPME method as an alternative to conventional techniques used in the evaluation of worker exposure to benzene, toluene, ethylbenzene, and xylene (BTEX). Polymethylsiloxane-carboxen (PDMS/CAR) showed as the most effective stationary phase material for sorbing BTEX among other materials (polyacrylate, PDMS, PDMS/divinylbenzene, Carbowax/divinylbenzene). Various experimental conditions were studied to apply SPME to BTEX quantitation in field situations. The uptake rate of the selected fiber (75 microm PDMS/CAR) was determined for each analyte at various concentrations, relative humidities, and airflow velocities from static (calm air) to dynamic (> 200 cm/s) conditions. The SPME method also was compared with the National Institute of Occupational Safety and Health method 1501. Unlike the latter, the SPME approach fulfills the new requirement for the threshold limit value-short term exposure limit (TLV-STEL) of 2.5 ppm for benzene (8 mg/m(3))

Reduction in the proportion of fevers associated with Plasmodium falciparum parasitaemia in Africa: a systematic review.

BACKGROUND: Malaria is almost invariably ranked as the leading cause of morbidity and mortality in Africa. There is growing evidence of a decline in malaria transmission, morbidity and mortality over the last decades, especially so in East Africa. However, there is still doubt whether this decline is reflected in a reduction of the proportion of malaria among fevers. The objective of this systematic review was to estimate the change in the Proportion of Fevers associated with Plasmodium falciparum parasitaemia (PFPf) over the past 20 years in sub-Saharan Africa. METHODS: Search strategy. In December 2009, publications from the National Library of Medicine database were searched using the combination of 16 MeSH terms.Selection criteria. Inclusion criteria: studies 1) conducted in sub-Saharan Africa, 2) patients presenting with a syndrome of 'presumptive malaria', 3) numerators (number of parasitologically confirmed cases) and denominators (total number of presumptive malaria cases) available, 4) good quality microscopy.Data collection and analysis. The following variables were extracted: parasite presence/absence, total number of patients, age group, year, season, country and setting, clinical inclusion criteria. To assess the dynamic of PFPf over time, the median PFPf was compared between studies published in the years ≤2000 and > 2000. RESULTS: 39 studies conducted between 1986 and 2007 in 16 different African countries were included in the final analysis. When comparing data up to year 2000 (24 studies) with those afterwards (15 studies), there was a clear reduction in the median PFPf from 44% (IQR 31-58%; range 7-81%) to 22% (IQR 13-33%; range 2-77%). This dramatic decline is likely to reflect a true change since stratified analyses including explanatory variables were performed and median PFPfs were always lower after 2000 compared to before. CONCLUSIONS: There was a considerable reduction of the proportion of malaria among fevers over time in Africa. This decline provides evidence for the policy change from presumptive anti-malarial treatment of all children with fever to laboratory diagnosis and treatment upon result. This should insure appropriate care of non-malaria fevers and rationale use of anti-malarials.

The effectiveness of brief alcohol interventions in primary care settings: A systematic review

Numerous studies have reported that brief interventions delivered in primary care are effective in reducing excessive drinking. However, much of this work has been criticised for being clinically unrepresentative. This review aimed to assess the effectiveness of brief interventions in primary care and determine if outcomes differ between efficacy and effectiveness trials. Approach. A pre-specified search strategy was used to search all relevant electronic databases up to 2006. The authors also hand-searched the reference lists of key articles and reviews. They included randomised controlled trials (RCT) involving patients in primary care who were not seeking alcohol treatment and who received brief intervention. Two authors independently abstracted data and assessed trial quality. Random effects meta-analyses, subgroup and sensitivity analyses and meta-regression were conducted.This resource was contributed by The National Documentation Centre on Drug Use.

Adult consequences of late adolescent alcohol consumption: a systematic review of cohort studies.

Alcohol is responsible for a significant portion of the global burden of disease. There is widespread concern reported in the media and other sources about drinking trends among young people, particularly heavy episodic or “binge” drinking. Prominent among policy responses, in the UK and elsewhere, have been attempts to manage antisocial behaviour related to intoxication in public spaces. Much less attention has been given to the longer term effects of excessive drinking in adolescence on later adult health and well-being. Some studies suggest that individuals “mature out” of late adolescent drinking behaviour, whilst others identify enduring effects on drinking and broader health and social outcomes in adulthood. If adolescent drinking does not cause later difficulties in adulthood then intervention approaches aimed at addressing the acute consequences of alcohol, such as unintentional injuries and anti-social behaviour, may be the most appropriate solution. If causal relationships do exist, however, this approach will not address the cumulative harms produced by alcohol, unless such intervention successfully modifies the long-term relationship with alcohol, which seems unlikely. To address this issue a systematic review of cohort studies was conducted, as this approach provides the strongest observational study design to evaluate evidence for causal inference.This resource was contributed by The National Documentation Centre on Drug Use.

Interventions to achieve long-term weight loss in obese older people: A systematic review and meta-analysis

The prevalence of obesity is rapidly increasing in older adults. Information is required about what interventions are effective in reducing obesity and influencing health outcomes in this age group. Thirteen databases were searched, earliest date 1966 to December 2008, including Medline, CINAHL, PsycINFO, the Cochrane database and EMBASE.

Interventions to achieve long-term weight loss in obese older people: A systematic review and meta-analysis

Purpose: the prevalence of obesity is rapidly increasing in older adults. Information is required about what interventions are effective in reducing obesity and influencing health outcomes in this age group. Design: systematic review and meta-analysis. Data sources: thirteen databases were searched, earliest date 1966 to December 2008, including Medline, CINAHL, PsycINFO, the Cochrane database and EMBASE. Study selection: we included studies with participants�۪ mean age 60 years and mean body mass index 30 kg/m2, with outcomes at a minimum of 1 year. Data were independently extracted by two reviewers and differences resolved by consensus. Data extraction: nine eligible trials were included. Study interventions targeted diet, physical activity and mixed approaches. Populations included patients with coronary artery disease, diabetes mellitus and osteoarthritis. Results: meta-analysis (seven studies) demonstrated a modest but significant weight loss of 3.0 kg [95% confidence interval (CI) 5.1���0.9] at 1 year. Total cholesterol (four studies) did not show a significant change: ���0.36 mmol/l (95% CI ���0.75 to 0.04). There was no significant change in high-density lipoprotein, low-density lipoprotein or triglycerides. In one study, recurrence of hypertension or cardiovascular events was significantly reduced (hazard ratio 0.65, 95% CI 0.50���0.85). Six-minute walk test did not significantly change in one study. Health-related quality of life significantly improved in one study but did not improve in a second study. Conclusions: although modest weight reductions were observed, there is a lack of high-quality evidence to support the efficacy of weight loss programmes in older people. ��Keywords: obesity, older, weight loss, meta-analysis, elderly, systematic review

Instruments measuring spirituality in clinical research: a systematic review.

INTRODUCTION: Numerous instruments have been developed to assess spirituality and measure its association with health outcomes. This study's aims were to identify instruments used in clinical research that measure spirituality; to propose a classification of these instruments; and to identify those instruments that could provide information on the need for spiritual intervention. METHODS: A systematic literature search in MEDLINE, CINHAL, PsycINFO, ATLA, and EMBASE databases, using the terms "spirituality" and "adult$," and limited to journal articles was performed to identify clinical studies that used a spiritual assessment instrument. For each instrument identified, measured constructs, intended goals, and data on psychometric properties were retrieved. A conceptual and a functional classification of instruments were developed. RESULTS: Thirty-five instruments were retrieved and classified into measures of general spirituality (N = 22), spiritual well-being (N = 5), spiritual coping (N = 4), and spiritual needs (N = 4) according to the conceptual classification. Instruments most frequently used in clinical research were the FACIT-Sp and the Spiritual Well-Being Scale. Data on psychometric properties were mostly limited to content validity and inter-item reliability. According to the functional classification, 16 instruments were identified that included at least one item measuring a current spiritual state, but only three of those appeared suitable to address the need for spiritual intervention. CONCLUSIONS: Instruments identified in this systematic review assess multiple dimensions of spirituality, and the proposed classifications should help clinical researchers interested in investigating the complex relationship between spirituality and health. Findings underscore the scarcity of instruments specifically designed to measure a patient's current spiritual state. Moreover, the relatively limited data available on psychometric properties of these instruments highlight the need for additional research to determine whether they are suitable in identifying the need for spiritual interventions.

Reduction of alcohol consumption by brief alcohol intervention in primary care: systematic review and meta-analysis.

BACKGROUND: Numerous trials of the efficacy of brief alcohol intervention have been conducted in various settings among individuals with a wide range of alcohol disorders. Nevertheless, the efficacy of the intervention is likely to be influenced by the context. We evaluated the evidence of efficacy of brief alcohol interventions aimed at reducing long-term alcohol use and related harm in individuals attending primary care facilities but not seeking help for alcohol-related problems. METHODS: We selected randomized trials reporting at least 1 outcome related to alcohol consumption conducted in outpatients who were actively attending primary care centers or seeing providers. Data sources were the Cochrane Central Register of Controlled Trials, MEDLINE, PsycINFO, ISI Web of Science, ETOH database, and bibliographies of retrieved references and previous reviews. Study selection and data abstraction were performed independently and in duplicate. We assessed the validity of the studies and performed a meta-analysis of studies reporting alcohol consumption at 6 or 12 months of follow-up. RESULTS: We examined 19 trials that included 5639 individuals. Seventeen trials reported a measure of alcohol consumption, of which 8 reported a significant effect of intervention. The adjusted intention-to-treat analysis showed a mean pooled difference of -38 g of ethanol (approximately 4 drinks) per week (95% confidence interval, -51 to -24 g/wk) in favor of the brief alcohol intervention group. Evidence of other outcome measures was inconclusive. CONCLUSION: Focusing on patients in primary care, our systematic review and meta-analysis indicated that brief alcohol intervention is effective in reducing alcohol consumption at 6 and 12 months.

Sociodemographic and occupational risk factors associated with the development of different burnout types: the cross-sectional University of Zaragoza study

BACKGROUND: Three different burnout types have been described: The "frenetic" type describes involved and ambitious subjects who sacrifice their health and personal lives for their jobs; the "underchallenged" type describes indifferent and bored workers who fail to find personal development in their jobs, and the "worn-out" in type describes neglectful subjects who feel they have little control over results and whose efforts go unacknowledged. The study aimed to describe the possible associations between burnout types and general sociodemographic and occupational characteristics. METHODS: A cross-sectional study was carried out on a multi-occupational sample of randomly selected university employees (n = 409). The presence of burnout types was assessed by means of the "Burnout Clinical Subtype Questionnaire (BCSQ-36)", and the degree of association between variables was assessed using an adjusted odds ratio (OR) obtained from multivariate logistic regression models. RESULTS: Individuals working more than 40 hours per week presented with the greatest risk for "frenetic" burnout compared to those working fewer than 35 hours (adjusted OR = 5.69; 95% CI = 2.52-12.82; p < 0.001). Administration and service personnel presented the greatest risk of "underchallenged" burnout compared to teaching and research staff (adjusted OR = 2.85; 95% CI = 1.16-7.01; p = 0.023). Employees with more than sixteen years of service in the organisation presented the greatest risk of "worn-out" burnout compared to those with less than four years of service (adjusted OR = 4.56; 95% CI = 1.47-14.16; p = 0.009). CONCLUSIONS: This study is the first to our knowledge that suggests the existence of associations between the different burnout subtypes (classified according to the degree of dedication to work) and the different sociodemographic and occupational characteristics that are congruent with the definition of each of the subtypes. These results are consistent with the clinical profile definitions of burnout syndrome. In addition, they assist the recognition of distinct profiles and reinforce the idea of differential characterisation of the syndrome for more effective treatment.

Identifying pesticide use patterns among flower growers to assess occupational exposure to mixtures

Objectives Exposure assessment to a single pesticide does not capture the complexity of the occupational exposure. Recently, pesticide use patterns analysis has emerged as an alternative to study these exposures. The aim of this study is to identify the pesticide use pattern among flower growers in Mexico participating in the study on the endocrine and reproductive effects associated with pesticide exposure. Methods A cross-sectional study was carried out to gather retrospective information on pesticide use applying a questionnaire to the person in charge of the participating flower growing farms. Information about seasonal frequency of pesticide use (rainy and dry) for the years 2004 and 2005 was obtained. Principal components analysis was performed. Results Complete information was obtained for 88 farms and 23 pesticides were included in the analysis. Six principal components were selected, which explained more than 70% of the data variability. The identified pesticide use patterns during both years were: 1. fungicides benomyl, carbendazim, thiophanate and metalaxyl (both seasons), including triadimephon during the rainy season, chlorotalonyl and insecticide permethrin during the dry season; 2. insecticides oxamyl, biphenthrin and fungicide iprodione (both seasons), including insecticide methomyl during the dry season; 3. fungicide mancozeb and herbicide glyphosate (only during the rainy season); 4. insecticides metamidophos and parathion (both seasons); 5. insecticides omethoate and methomyl (only rainy season); and 6. insecticides abamectin and carbofuran (only dry season). Some pesticides do not show a clear pattern of seasonal use during the studied years. Conclusions The principal component analysis is useful to summarise a large set of exposure variables into smaller groups of exposure patterns, identifying the mixtures of pesticides in the occupational environment that may have an interactive effect on a particular health effect.

High prevalence of drug-resistant tuberculosis and other mycobacteria among HIV-infected patients in Brazil: a systematic review

There is a little-noticed trend involving human immunodeficiency virus (HIV)-infected patients suspected of having tuberculosis: the triple-treatment regimen recommended in Brazil for years has been potentially ineffective in over 30% of the cases. This proportion may be attributable to drug resistance (to at least 1 drug) and/or to infection with non-tuberculous mycobacteria. This evidence was not disclosed in official statistics, but arose from a systematic review of a few regional studies in which the diagnosis was reliably confirmed by mycobacterial culture. This paper clarifies that there has long been ample evidence for the potential benefits of a four-drug regimen for co-infected patients in Brazil and it reinforces the need for determining the species and drug susceptibility in all positive cultures from HIV-positive patients.

Emerging pharmacotherapies for alcohol dependence: a systematic review focusing on reduction in consumption.

BACKGROUND: European Medicines Agency guidelines recognize two different treatment goals for alcohol dependence: abstinence and reduction in alcohol consumption. All currently approved agents are indicated for abstinence. This systematic review aimed to identify drugs in development for alcohol dependence treatment and to establish, based upon trial design, if any are seeking market authorization for reduction in consumption. METHODS: We searched PubMed and Embase (December 2001-November 2011) to identify agents in development for alcohol dependence treatment. Additional studies were identified by searching ClinicalTrials.gov and the R&D Insight and Clinical Trials Insight databases. Studies in which the primary focus was treatment of comorbidity, or n≤20, were excluded. Studies were then classified as 'abstinence' if they: described a detoxification/alcohol withdrawal period; enrolled patients who had undergone detoxification previously; or presented relapse/abstinence rates as the primary outcome. Studies in patients actively drinking at baseline were classified as 'reduction in consumption'. RESULTS: Of 602 abstracts identified, 45 full-text articles were eligible. Five monotherapies were in development for alcohol dependence treatment: topiramate, fluvoxamine, aripiprazole, flupenthixol and nalmefene. Nalmefene was the only agent whose sponsor was clearly seeking definitive approval for reduction in consumption. Development status was unclear for topiramate, fluvoxamine, aripiprazole and flupenthixol. Fifteen agents were examined in published exploratory investigator-initiated trials; the majority focused on abstinence. Ongoing (unpublished) trials tended to focus on reduction in consumption. CONCLUSIONS: While published studies generally focused on abstinence, ongoing trials focused on reduction in consumption, suggesting a change in emphasis in the approach to treating alcohol dependence.

Pragmatic approach for interpreting antiretroviral drug concentrations based on a systematic review of population pharmacokinetic studies

Objectives: The study objective was to derive reference pharmacokinetic curves of antiretroviral drugs (ART) based on available population pharmacokinetic (Pop-PK) studies that can be used to optimize therapeutic drug monitoring guided dosage adjustment.¦Methods: A systematic search of Pop-PK studies of 8 ART in adults was performed in PubMed. To simulate reference PK curves, a summary of the PK parameters was obtained for each drug based on meta-analysis approach. Most models used one-compartment model, thus chosen as reference model. Models using bi-exponential disposition were simplified to one-compartment, since the first distribution phase was rapid and not determinant for the description of the terminal elimination phase, mostly relevant for this project. Different absorption were standardized for first-order absorption processes.¦Apparent clearance (CL), apparent volume of distribution of the terminal phase (Vz) and absorption rate constant (ka) and inter-individual variability were pooled into summary mean value, weighted by number of plasma levels; intra-individual variability was weighted by number of individuals in each study.¦Simulations based on summary PK parameters served to construct concentration PK percentiles (NONMEM®).¦Concordance between individual and summary parameters was assessed graphically using Forest-plots. To test robustness, difference in simulated curves based on published and summary parameters was calculated using efavirenz as probe drug.¦Results: CL was readily accessible from all studies. For studies with one-compartment, Vz was central volume of distribution; for two-compartment, Vz was CL/λz. ka was directly used or derived based on the mean absorption time (MAT) for more complicated absorption models, assuming MAT=1/ka.¦The value of CL for each drug was in excellent agreement throughout all Pop-PK models, suggesting that minimal concentration derived from summary models was adequately characterized. The comparison of the concentration vs. time profile for efavirenz between published and summary PK parameters revealed not more than 20% difference. Although our approach appears adequate for estimation of elimination phase, the simplification of absorption phase might lead to small bias shortly after drug intake.¦Conclusions: Simulated reference percentile curves based on such an approach represent a useful tool for interpretating drug concentrations. This Pop-PK meta-analysis approach should be further validated and could be extended to elaborate more sophisticated computerized tool for the Bayesian TDM of ART.