Biological Monitoring of Blood Naphthalene Levels as a Marker of Occupational Exposure to PAHs among Auto-Mechanics and Spray Painters in Rawalpindi

<p>Abstract</p> <p>Background</p> <p>Routine exposure to chemical contaminants in workplace is a cause for concern over potential health risks to workers. In Pakistan, reports on occupational exposure and related health risks are almost non-existent, which reflects the scarce availability of survey data and criteria for determining whether an unsafe exposure has occurred. The current study was designed to evaluate blood naphthalene (NAPH) levels as an indicator of exposure to polycyclic aromatic hydrocarbons (PAHs) among automobile workshop mechanics (MCs) and car-spray painters (PNs). We further determined the relationship between blood NAPH levels and personal behavioural, job related parameters and various environmental factors that may further be associated with elevated risks of occupational exposures to PAHs.</p> <p>Methods</p> <p>Sixty blood samples (n = 20 for each group i.e. MC, PN and control group) were collected to compare their blood NAPH levels among exposed (MCs and PNs) and un-exposed (control) groups. Samples were analyzed using high pressure liquid chromatography (HPLC). Data regarding demographic aspects of the subjects and their socioeconomic features were collected using a questionnaire. Subjects were also asked to report environmental hygiene conditions of their occupational environment.</p> <p>Results</p> <p>We identified automobile work areas as potential sites for PAHs exposure, which was reflected by higher blood NAPH levels among MCs. Blood NAPH levels ranged from 53.7 to 1980.6 μgL^-1and 54.1 to 892.9 μgL^-1among MCs and PNs respectively. Comparison within each group showed that smoking enhanced exposure risks several fold and both active and passive smoking were among personal parameters that were significantly correlated with log-transformed blood NAPH levels. For exposed groups, work hours and work experience were job related parameters that showed strong associations with the increase in blood NAPH levels. Poor workplace hygiene and ventilation were recognized as most significant predictors related to differences among workplaces that may enhance the extent of exposure to chemical contaminants.</p> <p>Conclusions</p> <p>It appeared that chemical exposure at the workplace may be influenced by multiple environmental factors, but poor workplace hygiene and duration of exposure (long work hours) were the most important factors. Smoking and negligence of workers regarding self protection were among some of the important personal behaviours than can be addressed with better training. There is also a need to improve workplaces hygiene and to rationalize work hours to minimize health risks. Since smoking was an important confounding factor that supplemented most of the actual occupational exposure, a study based on non-smoker subjects is needed to separate out the effects of smoking and other confounding factors that may obscure measurements of actual extent of occupational exposure.</p

A comparative study of non-viral gene delivery techniques to human adipose-derived mesenchymal stem cell

Mesenchymal stem cells (MSCs) hold tremendous potential for therapeutic use in stem cell-based gene therapy. Ex vivo genetic modification of MSCs with beneficial genes of interest is a prerequisite for successful use of stem cell-based therapeutic applications. However, genetic manipulation of MSCs is challenging because they are resistant to commonly used methods to introduce exogenous DNA or RNA. Herein we compared the effectiveness of several techniques (classic calcium phosphate precipitation, cationic polymer, and standard electroporation) with that of microporation technology to introduce the plasmid encoding for angiopoietin-1 (ANGPT-1) and enhanced green fluorescent protein (eGFP) into human adipose-derived MSCs (hAD-MSCs). The microporation technique had a higher transfection efficiency, with up to 50% of the viable hAD-MSCs being transfected, compared to the other transfection techniques, for which less than 1% of cells were positive for eGFP expression following transfection. The capability of cells to proliferate and differentiate into three major lineages (chondrocytes, adipocytes, and osteocytes) was found to be independent of the technique used for transfection. These results show that the microporation technique is superior to the others in terms of its ability to transfect hAD-MSCs without affecting their proliferation and differentiation capabilities. Therefore, this study provides a foundation for the selection of techniques when using ex vivo gene manipulation for cell-based gene therapy with MSCs as the vehicle for gene delivery

Reverse phase high performance liquid chromatographic method development based on ultravioletvisible detector for the analysis of 1-hydroxypyrene (PAH biomarker) in human urine

Objectives: 1-hydroxypyrene is an important biomarker of exposure to polycyclic aromatic hydrocarbons (PAHs), which appears in the urine of exposed human subjects. In developing countries, where advanced instruments are not available, the importance of this biomarker demands convenient and sensitive methods for determination purposes. This study aimed at developing a methodology to quantify 1-hydroxypyrene (a biomarker of PAHs exposure) based on the UV-visible detector in the reverse phase high pressure liquid chromatography (HPLC). Material and Methods: A 20 μl injection of sample was used for manual injection into the HPLC Shimadzu, equipped with the SPD-20 A UV-visible detector, the LC-20AT pump and the DGU-20A5 degasser. The C-18 column was used for the purpose of the analysis. Results: The method showed a good linearity (the range: R2 = 0.979–0.989), and high detectability up to the nmol level. The average retention was 6.37, with the accuracy of 2%, and the percentage of recovery remained 108%. The overall performance of this method was comparable (in terms of detection sensitivity) and relatively better than previously reported studies using the HPLC system equipped with the UV-detector. Conclusions: This method is suitable and reliable for the detection/quantification of the 1-OHP in human urine samples, using the UV-detector, however, it is less sensitive as compared to the results of a florescence detector

Can home visits for early child development be implemented with sufficient coverage and quality at scale? Evidence from the SPRING program in India and Pakistan

INTRODUCTION: There is limited evidence from low and middle-income settings on the effectiveness of early child development interventions at scale. To bridge this knowledge-gap we implemented the SPRING home visiting program where we tested integrating home visits into an existing government program (Pakistan) and employing a new cadre of intervention workers (India). We report the findings of the process evaluation which aimed to understand implementation. METHODS AND MATERIALS: We collected qualitative data on acceptability and barriers and facilitators for change through 24 in-depth interviews with mothers; eight focus group discussions with mothers, 12 with grandmothers, and 12 with fathers; and 12 focus group discussions and five in-depth interviews with the community-based agents and their supervisors. RESULTS: Implementation was sub-optimal in both settings. In Pakistan issues were low field-supervision coverage and poor visit quality related to issues scheduling supervision, a lack of skill development, high workloads and competing priorities. In India, issues were low visit coverage - in part due to employing new workers and an empowerment approach to visit scheduling. Coaching caregivers to improve their skills was sub-optimal in both sites, and is likely to have contributed to caregiver perceptions that the intervention content was not new and was focused on play activities rather than interaction and responsivity - which was a focus of the coaching. In both sites caregiver time pressures was a key reason for low uptake among families who received visits. DISCUSSION: Programs need feasible strategies to maximize quality, coverage and supervision including identifying and managing problems through monitoring and feedback loops. Where existing community-based agents are overstretched and system strengthening is unlikely, alternative implementation strategies should be considered such as group delivery. Core intervention ingredients such as coaching should be prioritized and supported during training and implementation. Given that time and resource constraints were a key barrier for families a greater focus on communication, responsivity and interaction during daily activities could have improved feasibility

SYMBIOTICALLY SNAPPER SHRIMP ANCHISTUS CUSTOIDES BRUCE, 1977 (DECAPODA: PALAEMONIDAE) INHABITING THE MANTLE CAVITY OF THE PEN SHELL (BIVALVIA: PINNIDAE)

Snapper shrimp is a symbiotic organism usually hidden under the rocks, sponges and pen shells in the seagrass and coral habitats. The relationship study within snapper shrimp and pen shell was conducted from Merambong shoal, one of the biggest seagrass beds in peninsular Malaysia. A total of 40 individual pen shells were collected randomly and four species of pen shells were identified. 40 Anchistus custoides were found inhabiting symbiotically in the mantle cavity of the pen shell as solitary males and females and heterosexual pairs. Pen shell, Pinna bicolor and Atrina vexillum recorded the highest average SH 217.79±53.15 mm, SV 2.62±1.36 dm3 and SH 164.10-224.78 mm with the SV 1.18±0.43 dm3, respectively compared to the other species. The size of Anchistus custoides ranged from 15.00 to 20.00 mm in length and it was determined to be female due to the presence of eggs in the pleopods. The length of the cephalothorax and its length were highly related (rs=0.563, p≤0.01, N=40) and found wider in females. A little difference in size between the left and right chela in males of identical length was noticed, although the left chela is much bigger than the right. The significant relationship (rs=0.450, p≤0.01, N=40) between the pen shell length and shrimp (male-female) length revealed that the size of the shell is important to be hosted the snapper shrimp in the shell cavity

Effect of the SPRING home visits intervention on early child development and growth in rural India and Pakistan: parallel cluster randomised controlled trials

INTRODUCTION: Almost 250 million children fail to achieve their full growth or developmental potential, trapping them in a cycle of continuing disadvantage. Strong evidence exists that parent-focussed face to face interventions can improve developmental outcomes; the challenge is delivering these on a wide scale. SPRING (Sustainable Programme Incorporating Nutrition and Games) aimed to address this by developing a feasible affordable programme of monthly home visits by community-based workers (CWs) and testing two different delivery models at scale in a programmatic setting. In Pakistan, SPRING was embedded into existing monthly home visits of Lady Health Workers (LHWs). In India, it was delivered by a civil society/non-governmental organisation (CSO/NGO) that trained a new cadre of CWs. METHODS: The SPRING interventions were evaluated through parallel cluster randomised trials. In Pakistan, clusters were 20 Union Councils (UCs), and in India, the catchment areas of 24 health sub-centres. Trial participants were mother-baby dyads of live born babies recruited through surveillance systems of 2 monthly home visits. Primary outcomes were BSID-III composite scores for psychomotor, cognitive and language development plus height for age z-score (HAZ), assessed at 18 months of age. Analyses were by intention to treat. RESULTS: 1,443 children in India were assessed at age 18 months and 1,016 in Pakistan. There was no impact in either setting on ECD outcomes or growth. The percentage of children in the SPRING intervention group who were receiving diets at 12 months of age that met the WHO minimum acceptable criteria was 35% higher in India (95% CI: 4-75%, p = 0.023) and 45% higher in Pakistan (95% CI: 15-83%, p = 0.002) compared to children in the control groups. DISCUSSION: The lack of impact is explained by shortcomings in implementation factors. Important lessons were learnt. Integrating additional tasks into the already overloaded workload of CWs is unlikely to be successful without additional resources and re-organisation of their goals to include the new tasks. The NGO model is the most likely for scale-up as few countries have established infrastructures like the LHW programme. It will require careful attention to the establishment of strong administrative and management systems to support its implementation

Trachoma Prevalence in Four Localities of Darfur Region, Sudan, following One Round of Antibiotic Mass Drug Administration.

INTRODUCTION: The prevalence of trachomatous inflammation - follicular (TF) in 1-9-year-olds and of trachomatous trichiasis (TT) in ≥15-year-olds in four endemic evaluation units (EUs) of Darfur region, Sudan, was measured more than a year after the required single round of antibiotic mass drug administration (MDA). METHODS: Surveys were conducted using highly standardised, World Health Organization-recommended methodologies. Individuals aged ≥1 year, resident in selected households, were chosen for the survey using a two-stage cluster sampling process. Consenting adults and children were examined for the signs TF and TT by graders trained to international standards. Prevalence of disease in key indicator groups was calculated and weighted to the underlying population structure. RESULTS: A mean of 1,415 (range: 1,253-1,611) children aged 1-9 years were examined in each EU. The age-adjusted prevalence of TF in 1-9-year-olds in each of the four surveyed EUs was <5%. A mean of 1,139 people aged ≥15 years (range: 1,080-1,201) were examined in each EU. The estimated age- and gender-adjusted prevalence of TT in ≥15-year-olds was <0.2% in all four EUs. In general, the proportion of households with access to improved WASH facilities was generally lower in this study than in corresponding baseline studies. CONCLUSIONS: No further MDA should be conducted in these four EUs for the next 2 years, at which point they should be re-surveyed to determine whether the prevalence of TF in 1-9-year-olds has remained <5%. Active TT case-finding is also not indicated. Environmental improvement and promotion of facial cleanliness measures should continue to be implemented to prevent disease recrudescence

Can home visits for early child development be implemented with sufficient coverage and quality at scale? Evidence from the SPRING program in India and Pakistan

IntroductionThere is limited evidence from low and middle-income settings on the effectiveness of early child development interventions at scale. To bridge this knowledge-gap we implemented the SPRING home visiting program where we tested integrating home visits into an existing government program (Pakistan) and employing a new cadre of intervention workers (India). We report the findings of the process evaluation which aimed to understand implementation.Methods and materialsWe collected qualitative data on acceptability and barriers and facilitators for change through 24 in-depth interviews with mothers; eight focus group discussions with mothers, 12 with grandmothers, and 12 with fathers; and 12 focus group discussions and five in-depth interviews with the community-based agents and their supervisors.ResultsImplementation was sub-optimal in both settings. In Pakistan issues were low field-supervision coverage and poor visit quality related to issues scheduling supervision, a lack of skill development, high workloads and competing priorities. In India, issues were low visit coverage - in part due to employing new workers and an empowerment approach to visit scheduling. Coaching caregivers to improve their skills was sub-optimal in both sites, and is likely to have contributed to caregiver perceptions that the intervention content was not new and was focused on play activities rather than interaction and responsivity - which was a focus of the coaching. In both sites caregiver time pressures was a key reason for low uptake among families who received visits.DiscussionPrograms need feasible strategies to maximize quality, coverage and supervision including identifying and managing problems through monitoring and feedback loops. Where existing community-based agents are overstretched and system strengthening is unlikely, alternative implementation strategies should be considered such as group delivery. Core intervention ingredients such as coaching should be prioritized and supported during training and implementation. Given that time and resource constraints were a key barrier for families a greater focus on communication, responsivity and interaction during daily activities could have improved feasibility

Accelerated microwave curing of fibre-reinforced thermoset polymer composites for structural applications: A review of scientific challenges

Accelerated curing of high performance fibre-reinforced polymer (FRP) composites via microwave heating or radiation, which can significantly reduce cure time and increase energy efficiency, has several major challenges (e.g. uneven depth of radiation penetration, reinforcing fibre shielding, uneven curing, introduction of hot spots etc). This article reviews the current scientific challenges with microwave curing of FRP composites considering the underlying physics of microwave radiation absorption in thermoset-matrix composites. The fundamental principles behind efficient accelerated curing of composites using microwave radiation heating are reviewed and presented, especially focusing on the relation between penetration depth, microwave frequency, dielectric properties and cure degree. Based on this review, major factors influencing microwave curing of thermoset-matrix composites are identified, and recommendations for efficient cure cycle design are provided

Effect of the SPRING home visits intervention on early child development and growth in rural India and Pakistan: parallel cluster randomised controlled trials

IntroductionAlmost 250 million children fail to achieve their full growth or developmental potential, trapping them in a cycle of continuing disadvantage. Strong evidence exists that parent-focussed face to face interventions can improve developmental outcomes; the challenge is delivering these on a wide scale. SPRING (Sustainable Programme Incorporating Nutrition and Games) aimed to address this by developing a feasible affordable programme of monthly home visits by community-based workers (CWs) and testing two different delivery models at scale in a programmatic setting. In Pakistan, SPRING was embedded into existing monthly home visits of Lady Health Workers (LHWs). In India, it was delivered by a civil society/non-governmental organisation (CSO/NGO) that trained a new cadre of CWs.MethodsThe SPRING interventions were evaluated through parallel cluster randomised trials. In Pakistan, clusters were 20 Union Councils (UCs), and in India, the catchment areas of 24 health sub-centres. Trial participants were mother-baby dyads of live born babies recruited through surveillance systems of 2 monthly home visits. Primary outcomes were BSID-III composite scores for psychomotor, cognitive and language development plus height for age z-score (HAZ), assessed at 18 months of age. Analyses were by intention to treat.Results1,443 children in India were assessed at age 18 months and 1,016 in Pakistan. There was no impact in either setting on ECD outcomes or growth. The percentage of children in the SPRING intervention group who were receiving diets at 12 months of age that met the WHO minimum acceptable criteria was 35% higher in India (95% CI: 4–75%, p = 0.023) and 45% higher in Pakistan (95% CI: 15–83%, p = 0.002) compared to children in the control groups.DiscussionThe lack of impact is explained by shortcomings in implementation factors. Important lessons were learnt. Integrating additional tasks into the already overloaded workload of CWs is unlikely to be successful without additional resources and re-organisation of their goals to include the new tasks. The NGO model is the most likely for scale-up as few countries have established infrastructures like the LHW programme. It will require careful attention to the establishment of strong administrative and management systems to support its implementation