Comparison of two detection methods in thin layer chromatographic analysis of some herbicides in a Coastal Savanna Soil in Ghana

o-tolidine plus potassium iodide and photosynthesis inhibition detection methods were investigated for the analysis of three triazine herbicides (atrazine, ametryne, simazine) and two urea herbicides (diuron, metobromuron) in a coastal savanna soil using thin layer chromatography to compare the suitability of the two methods for the study of the herbicides. This was done by spiking 5 g of the soil sample with specific amount of the herbicide standards to generate herbicide-soil concentration of 40.24, 41.46, 40.28, 39.90 and 40.64 ìg/g for atrazine, ametryne, simazine, diuron and metobromuron, respectively. Extraction was performed with acetone/hexane mixture (4:1) and the detection limit of each herbicide was then determined. In all, the photosynthesis inhibition method performed better for both the triazine and the urea herbicides, while the o-tolidine plus potassium iodide method was suitable for only the triazine herbicides. With the photosynthesis inhibition method, detectability in the range of 0.004–0.008 ± 0.002 ìg/g was attained for the herbicides using the unclean extracts. In the case of o-tolidine plus potassium iodide method, detectability of 0.008–0.406 ± 0.02 ìg/g was obtained. With the clean up extracts detectability in the range of 0.025–0.162 ± 0.004 ìg/g was obtained using the photosynthesis inhibition method. However, metobromuron was not detected in the cleaned up extracts when o-tolidine plus potassium iodide detection method was used. For the methods described, clean up with SPE cartridge, equipped with C-18, is not critical to obtain the desired results

Pesticide residues in fish from the Densu River Basin in Ghana

The Densu River is a typical river flowing through agricultural areas in Southern Ghana. Six fish species from different locations in the river were sampled and analyzed for residues of pesticides and metabolites using GC with ECD/FID. The results of the study indicate that all the detected residues and metabolites in fish samples from the Densu River Basin were organochlorines (OCs). Among the pesticides residues analyzed, DDE, α-endosulfan, γ- HCH, δ- HCH, heptachlor and endosulfan sulphate, were predominant in all the samples. About 50% of the samples recorded positive detection of DDE while α-endosulfan was detected in 60% of the samples. γ- HCH, δ- HCH were detected in 75% and 65% of the samples respectively with heptachlor occurring in 80% of the samples. In almost all the fish species analyzed, DDE was the predominant compound having a mean value of 7.99 μgKg-1. Higher concentrations of pesticide residues were detected in fish samples from the Densu River at Nsawam than the other locations. The total concentration of residues in the fish samples ranged between 0.49 μgKg-1 and 8.90 μgKg-1 with the highest level detected in Hepsetue odoe (HO-N). The sequence of pesticide residues detected in fish samples were HO-N > HN-N > CO-N > CG-N > TZ-N > CN-W > TZ-W > CG-W. The high ratio of DDE/DDT in fish samples (0.1 – 6.9 with a mean of 2.51) indicated probably old input of DDT and significant degradation. The γ -HCH isomer (lindane) was the dominant HCH in fish samples suggesting a preferential usage of lindane (purified γ-HCH) in these areas. The δ-HCH/γ-HCH ratios in most fish samples were low indicating the present input of the pesticide lindane from non-point sources.Keywords: Pesticide residues, Fish, Densu River Basin, Ghana, exposur

Low fingertip temperature rebound measured by digital thermal monitoring strongly correlates with the presence and extent of coronary artery disease diagnosed by 64-slice multi-detector computed tomography

Previous studies showed strong correlations between low fingertip temperature rebound measured by digital thermal monitoring (DTM) during a 5 min arm-cuff induced reactive hyperemia and both the Framingham Risk Score (FRS), and coronary artery calcification (CAC) in asymptomatic populations. This study evaluates the correlation between DTM and coronary artery disease (CAD) measured by CT angiography (CTA) in symptomatic patients. It also investigates the correlation between CTA and a new index of neurovascular reactivity measured by DTM. 129 patients, age 63 ± 9 years, 68% male, underwent DTM, CAC and CTA. Adjusted DTM indices in the occluded arm were calculated: temperature rebound: aTR and area under the temperature curve aTMP-AUC. DTM neurovascular reactivity (NVR) index was measured based on increased fingertip temperature in the non-occluded arm. Obstructive CAD was defined as ≥50% luminal stenosis, and normal as no stenosis and CAC = 0. Baseline fingertip temperature was not different across the groups. However, all DTM indices of vascular and neurovascular reactivity significantly decreased from normal to non-obstructive to obstructive CAD [(aTR 1.77 ± 1.18 to 1.24 ± 1.14 to 0.94 ± 0.92) (P = 0.009), (aTMP-AUC: 355.6 ± 242.4 to 277.4 ± 182.4 to 184.4 ± 171.2) (P = 0.001), (NVR: 161.5 ± 147.4 to 77.6 ± 88.2 to 48.8 ± 63.8) (P = 0.015)]. After adjusting for risk factors, the odds ratio for obstructive CAD compared to normal in the lowest versus two upper tertiles of FRS, aTR, aTMP-AUC, and NVR were 2.41 (1.02–5.93), P = 0.05, 8.67 (2.6–9.4), P = 0.001, 11.62 (5.1–28.7), P = 0.001, and 3.58 (1.09–11.69), P = 0.01, respectively. DTM indices and FRS combined resulted in a ROC curve area of 0.88 for the prediction of obstructive CAD. In patients suspected of CAD, low fingertip temperature rebound measured by DTM significantly predicted CTA-diagnosed obstructive disease

Tea Consumption Enhances Endothelial-Dependent Vasodilation; a Meta-Analysis

Background: Tea consumption is associated with a lower risk of cardiovascular disease including stroke. Direct effects of tea components on the vasculature, particularly the endothelium, may partly explain this association. Objective: We performed a meta-analysis of controlled human intervention studies on the effect of tea on flow-mediated dilation (FMD) of the brachial artery, a measurement of endothelial function, which is suggested to be associated with cardiovascular risk. Methods: Human intervention studies were identified by systematic search of the databases Medline, Embase, Chemical Abstracts and Biosis through March 2009 and by hand-searching related articles. Studies were selected based on predefined criteria: intervention with tea as the sole experimental variable, placebo-controlled design, and no missing data on FMD outcome or its variability. A random effects model was used to calculate the pooled overall effect on FMD due to the intake of tea. The impact of various subject and treatment characteristics was investigated in the presence of heterogeneity. Results: In total, 9 studies from different research groups were included with 15 relevant study arms. The overall absolute increase in FMD of tea vs. placebo was 2.6 % of the arterial diameter (95 % CI: 1.8-3.3%; P-value,0.001) for a median daily dose of 500 mL of tea (2–3 cups). This is a relative increase of approximately 40 % compared to the average FMD of 6.3% measured under placebo or baseline conditions. There was significant heterogeneity between studies (P-value,0.001) tha

Improvements in access to malaria treatment in Tanzania following community, retail sector and health facility interventions -- a user perspective

BACKGROUND\ud \ud The ACCESS programme aims at understanding and improving access to prompt and effective malaria treatment. Between 2004 and 2008 the programme implemented a social marketing campaign for improved treatment-seeking. To improve access to treatment in the private retail sector a new class of outlets known as accredited drug dispensing outlets (ADDO) was created in Tanzania in 2006. Tanzania changed its first-line treatment for malaria from sulphadoxine-pyrimethamine (SP) to artemether-lumefantrine (ALu) in 2007 and subsidized ALu was made available in both health facilities and ADDOs. The effect of these interventions on understanding and treatment of malaria was studied in rural Tanzania. The data also enabled an investigation of the determinants of access to treatment.\ud \ud METHODS\ud \ud Three treatment-seeking surveys were conducted in 2004, 2006 and 2008 in the rural areas of the Ifakara demographic surveillance system (DSS) and in Ifakara town. Each survey included approximately 150 people who had suffered a fever case in the previous 14 days.\ud \ud RESULTS\ud \ud Treatment-seeking and awareness of malaria was already high at baseline, but various improvements were seen between 2004 and 2008, namely: better understanding causes of malaria (from 62% to 84%); an increase in health facility attendance as first treatment option for patients older than five years (27% to 52%); higher treatment coverage with anti-malarials (86% to 96%) and more timely use of anti-malarials (80% to 93-97% treatments taken within 24 hrs). Unfortunately, the change of treatment policy led to a low availability of ALu in the private sector and, therefore, to a drop in the proportion of patients taking a recommended malaria treatment (85% to 53%). The availability of outlets (health facilities or drug shops) is the most important determinant of whether patients receive prompt and effective treatment, whereas affordability and accessibility contribute to a lesser extent.\ud \ud CONCLUSIONS\ud \ud An integrated approach aimed at improving understanding and treatment of malaria has led to tangible improvements in terms of people's actions for the treatment of malaria. However, progress was hindered by the low availability of the first-line treatment after the switch to ACT

Perceptions and utilization of the anti-malarials artemether-lumefantrine and dihydroartemisinin-piperaquine in young children in the Chikhwawa District of Malawi: a mixed methods study

Background Adherence to anti-malarial dosing schedules is essential to ensure effective treatment. Measuring adherence is challenging due to recall issues and the participants’ awareness of the desired behaviour influencing their actions or responses. This study used qualitative methods, which allow for rapport building, to explore issues around anti-malarial utilization in young children, and used the results to guide the development of a context specific questionnaire on perceptions and adherence to artemether-lumefantrine (AL) and dihydroartemisinin-piperaquine (DHA-PPQ). Methods Qualitative data collection included 12 focus group discussions which explored community perceptions of anti-malarials and experiences of administering medications to children. Critical incidence interviews were conducted with 22 caregivers to explore experiences of administering the dispersible or original formulation of AL to young children during recent febrile episodes. A structured questionnaire was used to gather data on experience of recent treatment and adherence to anti-malarials during follow-up visits with 218 caregivers whose child was recently treated with either dispersible AL or DHA-PPQ. Discussion/Conclusion Caregivers experience great difficulty in administering medication to children. While the sweet taste of dispersible AL may have reduced conflict between the child and caregiver, sub-optimal dosing due to medication loss remained a problem and overall adherence was greater among those receiving DHA-PPQ, which requires fewer doses. Some caregivers were found to deliberately alter the dosing schedule according to whether they perceived the medication to be too weak or strong. They also developed theories for poor treatment outcomes, such as attributing this to lack of compatibility between the medication and the child. Health education messages should be strengthened to ensure a combination of clear pictorial and verbal instructions are used during dispensing, and consequences of under and over-dosing are explained alongside appropriate responses to possible adverse events. Further optimizing of anti-malarial adherence among children requires the development of anti-malarials with pharmacological properties that allow user-friendly administration and simplified dosing schedules

Global variation in anastomosis and end colostomy formation following left-sided colorectal resection

Background End colostomy rates following colorectal resection vary across institutions in high-income settings, being influenced by patient, disease, surgeon and system factors. This study aimed to assess global variation in end colostomy rates after left-sided colorectal resection. Methods This study comprised an analysis of GlobalSurg-1 and -2 international, prospective, observational cohort studies (2014, 2016), including consecutive adult patients undergoing elective or emergency left-sided colorectal resection within discrete 2-week windows. Countries were grouped into high-, middle- and low-income tertiles according to the United Nations Human Development Index (HDI). Factors associated with colostomy formation versus primary anastomosis were explored using a multilevel, multivariable logistic regression model. Results In total, 1635 patients from 242 hospitals in 57 countries undergoing left-sided colorectal resection were included: 113 (6·9 per cent) from low-HDI, 254 (15·5 per cent) from middle-HDI and 1268 (77·6 per cent) from high-HDI countries. There was a higher proportion of patients with perforated disease (57·5, 40·9 and 35·4 per cent; P < 0·001) and subsequent use of end colostomy (52·2, 24·8 and 18·9 per cent; P < 0·001) in low- compared with middle- and high-HDI settings. The association with colostomy use in low-HDI settings persisted (odds ratio (OR) 3·20, 95 per cent c.i. 1·35 to 7·57; P = 0·008) after risk adjustment for malignant disease (OR 2·34, 1·65 to 3·32; P < 0·001), emergency surgery (OR 4·08, 2·73 to 6·10; P < 0·001), time to operation at least 48 h (OR 1·99, 1·28 to 3·09; P = 0·002) and disease perforation (OR 4·00, 2·81 to 5·69; P < 0·001). Conclusion Global differences existed in the proportion of patients receiving end stomas after left-sided colorectal resection based on income, which went beyond case mix alone

Arsenic and mercury levels in human hairs and nails from gold mining areas in Wassa West district of Ghana

Hair and nail samples obtained from inhabitants of Wassa West District, a major gold mining area in Ghana, were analysed for arsenic (As) and mercury (Hg) using instrumental neutron activation analysis. The samples were irradiated at a thermal neutron flux of 5 x 10P11 Pn cmP-2P sP-1P using the Ghana Research Reactor. Concentrati-on of Hg in the hairs ranged from 1.65 to 20.46 μg/g, which were below World health Organization (WHO) recommended level of 50.00 μg/gP Pfor human hair. Mercury concentrations in human nail samples ranged from 0.97 to 31.94 μg/g. Arsenic concentrations in human hairs ranged from 0.07 to 0.95 μg/g, while the levels in nail samples ranged from 0.08 to 3.90 μg/g. Generally, levels of As in the hair were less than WHO recommended value of 1.00 μg/g, however, the levels of As in 5 nail samples (FNB11B, FNB20B, FNB28B, TNB9B and TNB16B) were above the maximum WHO value of 1.08μg/g. The measurement precision specified by the relative standard deviation was within ± 3 %. The accuracy of determination evaluated by analysing certified standard human hair reference material GBW 09101 was within ± 4 % of the certified value. The levels of As in hair and nail samples of the experimental group were generally higher as compared to the control subject. Similarly, Hg levels in the hair and nail samples in experimental group were also higher compared to the control subject. However, the levels of the toxic elements determined were all below WHO recommended values