University of Nigeria, Nsukka

About: University of Nigeria, Nsukka is a education organization based out in Nsukka, Nigeria. It is known for research contribution in the topics: Population & Health care. The organization has 10211 authors who have published 13685 publications receiving 138922 citations.

An antimalarial extract from neem leaves is antiretroviral

Abstract: An acetone-water neem leaf extract with antimalarial activity was evaluated in vitro at 5 microg/ml for inhibition of adhesion of malaria parasite-infected erythrocytes and cancer cells to endothelial cells, and at 10 microg/ml for protection of lymphocytes against invasion by HIV. The extract was also evaluated in 10 patients with HIV/AIDS at 1000 mg daily for 30 d. The mean binding of infected erythrocytes and cancer cells per endothelial cell was 15 and 11 respectively in the absence of the extract, and 0 and 2 respectively in with the extract. In the absence and presence of the extract, 0% and 75%, respectively, of lymphocytes were protected. In the treated patients, haemoglobin concentration, mean CD4+ cell count and erythrocyte sedimentation rate, which were initially 9.8 g/dl, 126 cells/microl and 90 mm/h respectively, improved to 12.1 g/dl, 241 cells/microl and 49 mm/h. Mean bodyweight and platelet count, initially 57 kg and 328 x 10(3)/mm3 respectively, increased to 60 kg and 359 x 10(3)/mm3. No adverse effects were observed during the study. The extract showed antiretroviral activity with a mechanism of action that may involve inhibition of cytoadhesion. The results may help in the development of novel antiretroviral and antimalarial drugs.

Structural, electronic, and optical properties of beryllium monochalcogenides

Abstract: The results of first-principles theoretical study of the structural, electronic and optical properties of beryllium monochalcogenides BeTe, BeSe and BeS, performed using the full potential linearized augmented plane wave (FP-LAPW) method are presented. The calculated structural parameters and band gaps compare very well with previous theoretical results. The trends of the band gap pressure coefficients and volume deformation potentials for these II-VI compounds are investigated. The linear pressure coefficients for the $\Gamma - $ X and $\Gamma - \Gamma$ band gaps increase with decrease in anion atomic weight. The dependence of the direct and indirect band gaps on the relative change of lattice constant are found to follow almost the same type of trends in each of these compounds. The volume deformation potential ( $a_{v}^{\alpha}$ ) for the direct ( $\alpha = \Gamma - \Gamma$ ) and indirect ( $\alpha = \Gamma - L$ ) gaps are positive, but negative for the indirect ( $\Gamma - {\rm X}$ ) gap. Furthermore, $a_{v}^{\alpha}$ , for $\alpha = \Gamma - {\rm X}$ transitions decreases with increase in anion atomic number whereas $a_{v}^{\Gamma-\Gamma}$ , increases. The optical properties have also been calculated. From the reflectivity spectra, the compounds will be useful for optical applications. The variation of the band gaps with respect to the application of pressure and the origin of some of the peaks in the optical spectra are discussed in terms the calculated electronic structure.

Calcined Corncob-Kaolinite Combo as New Sorbent for Sequestration of Toxic Metal Ions From Polluted Aqua Media and Desorption

Abstract: This study investigated a new area of improving the adsorption capacity of clay using corn cob as an alternative means of clay modification to the more expensive and complicated chemical treatment techniques. Kaolinite Clay (KC), Calcined corncob-kaolinite Combo (CCKC), and Corncob (CC) adsorbents were utilized. The adsorbents were characterized by Fourier Transform-Infrared (FT-IR) Spectroscopy, Scanning Electron Microscopy (SEM), X-ray fluorescence spectroscopy, and Brunauer-Emmett-Teller (BET) surface area analyzer. Batch adsorption methodology was used to investigate the effect of pH, initial metal concentration, adsorbent dose, and contact time on adsorption of Pb (II) and Cd (II). A slight increase in BET surface area of 29.31 m2/g for CCKC from 14.12 m2/g for raw KC was achieved. The trend of metal adsorption on the adsorbents was in the order CC>CCKC>KC. The Langmuir isotherm was found to present the best fit for the unmodified adsorbents while the Freundlich was applicable for CCKC indicating multilayer heterogeneous surface. The pseudo second order kinetic model was found to be suitable in the kinetic analysis. Thermodynamic studies revealed a spontaneous physical adsorption process of metal ions on CCKC. The combo adsorbent showed highest percentage desorption (>70%) of Cd and Pb ions in both acid and basic media compared to the other adsorbents. The results of the study established the efficiency of calcined corn cob kaolinite combo as suitable adsorbent for metal ions.

Hypothetical and actual willingness to pay for insecticide-treated nets in five Nigerian communities

Abstract: OBJECTIVES To determine the hypothetical and actual willingness of households to pay (WTP) for insecticide-treated nets (ITNs), and compare these in areas with and without previous exposure to free ITNs. METHODOLOGY The contingent valuation method was used to determine the willingness of the heads of 1908 randomly selected households from five communities in south-east Nigeria to pay for two sizes of ITNs. Two communities previously had free access to ITNs. Validity was assessed using multiple regression analyses, and by offering ITNs for sale to 200 randomly selected people drawn from the original sample. The data was collected between March and September 1998. FINDINGS Most respondents were willing to pay for ITNs: Mbano (93.26%), Ugwogo (97.69%), Orba (83.24%), Alor-uno (95.37%), and Ibagwa-ani (87.34%). In multivariate analyses, WTP was significantly associated with the number of people living in a household, sex of the respondent, average yearly expenditure on gifts and the type of savings scheme (P < 0.05). Some of the residences were also statistically significant in the two models used, and those with prior exposure to free ITNs were negatively related to WTP. Seventy-six percent of those who were hypothetically willing to pay actually purchased them, and the WTP technique correctly predicted the choices of 80% of the respondents. CONCLUSION There was good evidence that stated WTP could be translated into actual WTP. However, peoples' perception of affordability of the nets and its link to their WTP needs further exploration. The WTP technique is a potentially valid tool for market research in healthcare, as it was able to predict the direction of actual WTP for the ITNs. The hypothetical WTP amounts could be used as guide to know either the optimal price to charge for the ITNs or the level of subsidy to introduce.