Chemical Speciation and Mobility of Some Heavy Metals in Soils around Automobile Waste Dumpsites in Northern Part of Niger Delta, South Central Nigeria

The mobility of some heavy metals (Fe, Co, Ni and Mn) in soils around automobile waste dumpsites in Northern part of Niger Delta was assessed using Tessier et al. five syteps sequential chemical extraction procedure. The results showed that majority of iron and manganese were associated with the residual fraction with the average levels of 29.2% and 24.43% respectively. The exchangeable  fraction was the most important fraction for cobalt with the average level of 39.53%, while the organic fraction contained the predominant species of nickel with an average level of 22.97%. For the total concentrations of the metals, iron ranging from (mgkg-1) 768.30 to 2897.00 was the highest followed by manganese ranging from 1.78 to 19.92 and then cobalt and nickel which ranged from 0.28 to 2.42 and 0.084 to 0.512 respectively. The mobility factors for the metals in all the sites ranged from 20.37 to 90.90 for cobalt, 15.83 to 62.07 for nickel, 25.50 to 60.43 for manganese and 16.49 to 32.13 for iron following the order Co>Ni>Mn>Fe. The relatively high mobility factors observed for cobalt in some sites coupled with its comparatively high concentration in the exchangeable fraction, indicates high mobility, lability and bioavailability for cobalt in the soils studied. The other metals (Fe, Ni and Mn) which are strongly bound to soil matrix are not readily availably for introduction into the food chain. The results suggest that there is no serious contamination hazard with the metals studied, considering the geochemical phases in which Fe, Ni and Mn were associated with, and the low total metal concentration of Co, even with its relatively high mobility. @JASEM J. Appl. Sci. Environ. Manage. December, 2010, Vol. 14 (4) 123 - 13

Physicochemical Characteristics and Levels of Some Heavy Metals in Soils around Metal Scrap Dumps in Some Parts of Delta State, Nigeria

Some physicochemical characteristics and heavy metal levels in soil samples around metal scrap dumps at Abraka and Agbor vicinities of Delta State, Nigeria, were analysed in order to assess the effects of the dumps on the soils. Conventional analytical methods were employed for the determination of these physicochemical parameters while heavy metals in the soil samples where analysed using Atomic Absorption Spectrophotometer. The results of the physicochemical analysis showed that the pH values in all the sites ranged from 7.01 to 7.99 indicating neutrality to slight alkalinity of the soils. The Total Organic Carbon values ranged from 0.38 to 0.54% indicating presence of some organic matter and some microbiological activities in the soil samples. The high conductivity values ranging from 165 to 201μs/cm indicated significant presence of some soluble inorganic salts in soils studied. For all the physicochemical values recorded, the soil samples at Agbor had slightly higher values than those of Abraka. The heavy metal levels for the soils in Abraka and Agbor respectively were (mgkg-1) 1.50 and 1.52 for Cd, 5.10 and 4.48 for Ni, 1431 and 1411 for Fe, 74.26 and 97.21 for Zn, 14.31 and 34.21 for Cu, 24.0 and 18 for Cr, 9.73 and 10.54 for Co, and then 12.24 and 14.47 for Pb. The levels were all higher than those recorded in the control sites. A consistent trend showing a decrease in the concentration of heavy metals was observed for soil samples at increased distances from the impact points for the two towns studied. Metal was observed for soil samples at increased distances from the impact point for the two towns studied. The results from the contamination index indicated a significant degree of soil contamination for Pd, Cd, Co, Cu and Zn in the soils studied showing a higher degree of contamination for these metals. These soils therefore constitute a major health risk to the local population. This study successfully related and attributed the presence of heavy metals with anomalous concentration in the soils to anthropogenic inputs from the metal scrap dumps. @JASEM.J. Appl. Sci. Environ. Manage. December, 2010, Vol. 14 (4) 57 - 6

Glutathione and Adaptive Immune Responses against Mycobacterium tuberculosis Infection in Healthy and HIV Infected Individuals

Glutathione (GSH), a tripeptide antioxidant, is essential for cellular homeostasis and plays a vital role in diverse cellular functions. Individuals who are infected with Human immuno deficiency virus (HIV) are known to be susceptible to Mycobacterium tuberculosis (M. tb) infection. We report that by enhancing GSH levels, T-cells are able to inhibit the growth of M. tb inside macrophages. In addition, those GSH-replenished T cell cultures produced increased levels of Interleukin-2 (IL-2), Interleukin-12 (IL-12), and Interferon-gamma (IFN-γ), cytokines, which are known to be crucial for the control of intracellular pathogens. Our study reveals that T lymphocytes that are derived from HIV infected individuals are deficient in GSH, and that this deficiency correlates with decreased levels of Th1 cytokines and enhanced growth of M. tb inside human macrophages

Regional research priorities in brain and nervous system disorders

The characteristics of neurological, psychiatric, developmental and substance-use disorders in low-and middle-income countries are unique and the burden that they have will be different from country to country. Many of the differences are explained by the wide variation in population demographics and size, poverty, conflict, culture, land area and quality, and genetics. Neurological, psychiatric, developmental and substance-use disorders that result from, or are worsened by, a lack of adequate nutrition and infectious disease still afflict much of sub-Saharan Africa, although disorders related to increasing longevity, such as stroke, are on the rise. In the Middle East and North Africa, major depressive disorders and post-traumatic stress disorder are a primary concern because of the conflict-ridden environment. Consanguinity is a serious concern that leads to the high prevalence of recessive disorders in the Middle East and North Africa and possibly other regions. The burden of these disorders in Latin American and Asian countries largely surrounds stroke and vascular disease, dementia and lifestyle factors that are influenced by genetics. Although much knowledge has been gained over the past 10 years, the epidemiology of the conditions in low-and middle-income countries still needs more research. Prevention and treatments could be better informed with more longitudinal studies of risk factors. Challenges and opportunities for ameliorating nervous-system disorders can benefit from both local and regional research collaborations. The lack of resources and infrastructure for health-care and related research, both in terms of personnel and equipment, along with the stigma associated with the physical or behavioural manifestations of some disorders have hampered progress in understanding the disease burden and improving brain health. Individual countries, and regions within countries, have specific needs in terms of research priorities.Fil: Ravindranath, Vijayalakshmi. Indian Institute of Science; IndiaFil: Dang, Hoang Minh. Vietnam National University; VietnamFil: Goya, Rodolfo Gustavo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Bioquímicas de La Plata ; ArgentinaFil: Mansour, Hader. University of Pittsburgh; Estados Unidos. Mansoura University; EgiptoFil: Nimgaonkar, Vishwajit L.. University of Pittsburgh; Estados UnidosFil: Russell, Vivienne Ann. University of Cape Town; SudáfricaFil: Xin, Yu. Peking University; Chin

Efficacy of newer versus older antihypertensive drugs in black patients living in sub-Saharan Africa

To address the epidemic of hypertension in blacks born and living in sub-Saharan Africa, we compared in a randomised clinical trial (NCT01030458) single-pill combinations of old and new antihypertensive drugs in patients (30-69 years) with uncomplicated hypertension (140-179/90-109 mm Hg). After 4 weeks off treatment, 183 of 294 screened patients were assigned to once daily bisoprolol/hydrochlorothiazide 5/6.25 mg (n=89; R) or amlodipine/valsartan 5/160 mg (n=94; E) and followed up for 6 months. To control blood pressure (<140/<90 mm Hg), bisoprolol and amlodipine could be doubled (10 mg per day) and α-methyldopa (0.5-2 g per day) added. Sitting blood pressure fell by 19.5/12.0 mm Hg in R patients and by 24.8/13.2 mm Hg in E patients and heart rate decreased by 9.7 beats per minute in R patients with no change in E patients (-0.2 beats per minute). The between-group differences (R minus E) were 5.2 mm Hg (P<0.0001) systolic, 1.3 mm Hg (P=0.12) diastolic, and 9.6 beats per minute (P<0.0001). In 57 R and 67 E patients with data available at all visits, these estimates were 5.5 mm Hg (P<0.0001) systolic, 1.8 mm Hg (P=0.07) diastolic and 9.8 beats per minute (P<0.0001). In R compared with E patients, 45 vs 37% (P=0.13) proceeded to the higher dose of randomised treatment and 33 vs 9% (P<0.0001) had α-methyldopa added. There were no between-group differences in symptoms except for ankle oedema in E patients (P=0.012). In conclusion, new compared with old drugs lowered systolic blood pressure more and therefore controlled hypertension better in native African black patients.Journal of Human Hypertension advance online publication, 27 June 2013; doi:10.1038/jhh.2013.56.status: publishe