Comparative Studies of Some Polypores Using High Performance Liquid Chromatography

Isolates of four polypores; Ganoderma colossum, Ganoderma lucidum, Trametes cingulata and Daedalea quercina were compared using the High performance liquid chromatographic profiles of their triterpenoids. A higher abundance of colossolactone E was found in Ganoderma colossum isolate (FC 876) when compared with FC 872 obtained at different periods and dried differently and 23- hydroxycolossolactone E found in FC 876 was not observed in FC 872. Equal abundance of constituents was also found in Ganoderma lucidum isolates (FC 871 and FC 875) collected from different hosts and geographical locations. The isolates of Trametes cingulata that were of different ages showed predominance of the major constituents in FC 873 and FC 885 isolates when compared with FC 870. The abundance of the triterpenoid in the isolates of Daedalea quercina was almost doubled in FC 882 when compared with that of FC 878. These conform with the chemical spot test results on these polypores in a previous work. The ability of the polypores to produce triterpenoids is affected by their age, period of collection, geographical location and method of drying, which also affected the High Performance Liquid Chromatography characteristics of their secondary metabolites. African Research Review Vol. 1 (1) 2007: pp. 77-9

The potential impact of moxidectin on onchocerciasis elimination in Africa: an economic evaluation based on the Phase II clinical trial data

BACKGROUND: Spurred by success in several foci, onchocerciasis control policy in Africa has shifted from morbidity control to elimination of infection. Clinical trials have demonstrated that moxidectin is substantially more efficacious than ivermectin in effecting sustained reductions in skin microfilarial load and, therefore, may accelerate progress towards elimination. We compare the potential cost-effectiveness of annual moxidectin with annual and biannual ivermectin treatment. METHODS: Data from the first clinical study of moxidectin were used to parameterise the onchocerciasis transmission model EPIONCHO to investigate, for different epidemiological and programmatic scenarios in African savannah settings, the number of years and in-country costs necessary to reach the operational thresholds for cessation of treatment, comparing annual and biannual ivermectin with annual moxidectin treatment. RESULTS: Annual moxidectin and biannual ivermectin treatment would achieve similar reductions in programme duration relative to annual ivermectin treatment. Unlike biannual ivermectin treatment, annual moxidectin treatment would not incur a considerable increase in programmatic costs and, therefore, would generate sizeable in-country cost savings (assuming the drug is donated). Furthermore, the impact of moxidectin, unlike ivermectin, was not substantively influenced by the timing of treatment relative to seasonal patterns of transmission. CONCLUSIONS: Moxidectin is a promising new drug for the control and elimination of onchocerciasis. It has high programmatic value particularly when resource limitation prevents a biannual treatment strategy, or optimal timing of treatment relative to peak transmission season is not feasible. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s13071-015-0779-4) contains supplementary material, which is available to authorized users

Antimicrobial susceptibility pattern of Aeromonas hydrophila among patients presented with diarrhea attending two teaching hospitals in northern, Nigeria

A total of one hundred and twenty eight (128) stool samples were collected from patients attending Ahmadu Bello University Teaching Hospital Zaria and Aminu Kano Teaching Hospital Kano, and screened for the presence of Aeromonas hydrophila infection. Out of the one hundred and twenty eight samples analyzed 4 (3.12%) were found positive for Aeromonas hydrophila infection. Antibioticsusceptibility testing of Aeromonas hydrophila isolated showed that all the 4 (100%) isolates were sensitive to Colistin and Ceftazidime, 3 (75%) to Augmentin and 2(50%) to Gentamicin and Cefuroxine. All the isolates (100%) were however resistant to Cotrimoxazole, Tetracycline, Sulphatriad, Streptomycin, Cephalothin and Ampicilin. This study confirmed that Aeromonas hydrophila as a sole enteropathogen could be responsible for diarrhea and should be considered amongst the causative agents of diarrhea. Key words: Aeromonas, diarrhoea, antibiotic, susceptibility testing, ABUTH, AKTH

ASSOCIATE FACTORS AFFECTING THE GROWTH OF MICRO BUSINESS IN CALABAR, CROSS RIVER STATE, NIGERIA

The main objective of the study is to examine those associate factors affecting the growth of micro business in Calabar, Cross river state, Nigeria. The study is aimed to specifically investigate the extent to which lack of microcredit and crime affects the growth of micro business in Calabar. The cross sectional survey research design was used in selecting 287 business owners from 4 areas in Calabar, using the purposive sampling technique. The study used questionnaires to collect primary data. The questionnaire was checked for completion and reliability of the data. The quantitative data was then coded and analyzed using descriptive statistics such as percentages and mean and standard deviation. Descriptive statistics was used mainly to summarize the data. This included percentages and frequencies. Statistical Package for Social Sciences (SPSS version 20.0) was employed to aid in the coding, entry and analysis of the data obtained through the questionnaires. Result revealed that Lack of microcredit and crime significantly affects the growth of micro business in Calabar. Sequel to this outcome the study there by recommends amongst other factors that; the government should improve on the metropolitan security architectural network to curb urban crime. Provide mini credit scheme opportunity to deserving indigenes at bearable interest margin to deserving indigenes at bearable interest margin as well as the ancillary components like road network, water, transportation, power etc. that correlates performance in micro businesses.  Article visualizations

Effects of micronutrients on oxidative stress in HIV positive patients taking highly active antiretroviral therapy (HAART) in a tertiary health care facility in Kano, northwest Nigeria

The study examined the effects of micronutrients supplementation on oxidative stress markers in HIV positive patients on highly active antiretroviral therapy (HAART), attending Aminu Kano Teaching Hospital (AKTH) Kano-Nigeria. Fifty four (54) HIV positive individuals already taking HAART were placed on a daily dose of a multivitamin supplement for a period of three months. Another 54 HIV positive subjects who were already on HAART served as the control group for the same period of time. Prior to the multivitamin supplementation, the baseline mean serum vitamin A, C, and E, selenium, zinc, malondehaldehyde (MDA), albumin, total protein, and CD4+ count values were established. With the exception of mean serum vitamin C, the mean serum values for the studied parameters after the supplementation period increased significantly (P<0.05) in the non supplemented group compared to their baseline values. The mean serum vitamin A, C, and E, Se, total protein and CD4+ count of the supplemented group increased significantly when compared to their baseline values. Mean serum MDA was significantly decreased (P<0.05) in the multivitamin supplemented group compared to their baseline. No significant difference (P<0.05) was seen in the mean serum vitamin C and albumin of the multivitamin supplemented group as compared to their baseline. The mean serum vitamins A, C, and E and the CD4+ count of the multivitamins supplemented subjects significantly increased (P<0.05) when compared to that of the non supplemented subjects. Mean serum selenium and zinc increased significantly (P<0.05) in the non supplemented subjects but not in the supplemented subjects. The serum thiobarbituric acid reactive substances (TBARs) in the form of malondialdehyde (MDA), for the supplemented subjects was found to reduce significantly (P<0.05) compared to that of the non supplemented subjects. Statistical analysis showed no significant difference between the supplemented and the non supplemented subjects in their serum total protein and albumin. Among the supplemented Subjects, vitamin A and C increased significantly (P<0.05) in the ARV treatment naïve sub group. Vitamin E, selenium and zinc increased significantly (P<0.05) in the ARV treated sub group, while MDA decreased significantly (P<0.05) in this sub group. Micronutrient supplementation was therefore shown to reduce oxidative stress in HIV positive patients on HAART and could possibly be very helpful as an adjunct in the treatment of this disease.Key Words: Antiretroviral, micronutrients, malondialdehyde, ART naïve, reactive oxygen species, supplementation

Proton-bound dimers of nitrogen heterocyclic molecules: Substituent effects on the structures and binding energies of homodimers of diazine, triazine, and fluoropyridine

The bonding energies of proton-bound homodimers BH+B were measured by ion mobilityequilibrium studies and calculated at the DFT B3LYP/6-311++G* * level, for a series of nitrogen heterocyclic molecules (B) with electron-withdrawing in-ring N and on-ring F substituents. The binding energies (ΔH°dissoc) of the proton-bound dimers (BH+B) vary significantly, from 29.7 to 18.1 kcal/mol, decreasing linearly with decreasing the proton affinity of the monomer (B). This trend differs significantly from the constant binding energies of most homodimers of other organic nitrogen and oxygen bases. The experimentally measured ΔH°dissoc for (1,3-diazine)2H+, i.e., (pyrimidine)2H+ and (3-F-pyridine)2H+ are 22.7 and 23.0 kcal/mol, respectively. The measured ΔH°dissoc for the pyrimidine ·+(3-F-pyridine) radical cation dimer (19.2 kcal/mol) is signifcantly lower than that of the proton-bound homodimers of pyrimidine and 3-F-pyridine, reflecting the stronger interaction in the ionic H-bond of the protonated dimers. The calculated binding energies for (1,2-diazine)2H+, (pyridine)2H+, (2-F-pyridine)2H+, (3-F-pyridine)2H+, (2,6-di-F-pyridine)2H+, (4-F-pyridine)2H+, (1,3-diazine)2H+, (1,4-diazine)2H+, (1,3,5-triazine)2H+, and (pentafluoropyridine)2H+ are 29.7, 24.9, 24.8, 23.3, 23.2, 23.0, 22.4, 21.9, 19.3, and 18.1 kcal/mol, respectively. The electron-withdrawing substituents form internal dipoles whose electrostatic interactions contribute to both the decreased proton affinities of (B) and the decreased binding energies of the protonated dimers BH+B. The bonding energies also vary with rotation about the hydrogen bond, and they decrease in rotamers where the internal dipoles of the components are aligned efficiently for inter-ring repulsion. For compounds substituted at the 3 or 4 (meta or para) positions, the lowest energy rotamers are T-shaped with the planes of the two rings rotated by 90° about the hydrogen bond, while the planar rotamers are weakened by repulsion between the ortho hydrogen atoms of the two rings. Conversely, inortho-substituted (1,2-diazine)2H+ and (2-F-pyridine)2H+, attractive interactions between the ortho (C–H) hydrogen atoms of one ring and the electronegative ortho atoms (N or F) of the other ring are stabilizing, and increase the protonated dimer binding energies by up to 4 kcal/mol. In all of the dimers, rotation about the hydrogen bond can involve a 2–4 kcal/mol barrier due to the relative energies of the rotamers

Competence and enterprise of management as drivers of early foreign listing of medium-sized emerging market multinationals (EMNEs) from Africa

YesEMNEs from Africa are missing in global places and spaces, and Africapitalism is also meagrely represented within the capillaries of international investments, relative to the opportunities offered by globalisation and Africa’s rich natural resource endowment. Using the Penrosian MNE growth theory, we investigate how African firms' managerial competence and entrepreneurial behaviours can be enhanced by engaging foreign executive directors during pre, early and post-internationalisation. We conduct our analysis by using data from 157 companies domiciled in 17 African countries. Our results show that whilst access to liquidity, foreign managerial know-how, and experience are key drivers of early foreign listing of African EMNEs, these factors have less effect on corporate outcomes during the 3rd and 5th year without the moderating effect of foreign executive directors. We contribute to the international business and international entrepreneurship literature by showing that African EMNEs can succeed in global spaces if they leverage the expertise of foreign executive directors as they bring idiosyncratic industry and market knowledge during early internationalisation. EMNEs intending to internationalise must use a polycentric governing board structure to reflect the intended destination country. Our results imply that early listing on the international stock markets is among the key strategies latecomers use to enter a global game they are just learning to play

Mitigating the impact of climate change on UK buildings through zero energy strategies

It is currently established that one of the paramount concerns in the built environment is the energy efficiency of new and existing UK dwellings, respective to the unfavourable impacts posed to climate change. The Department for Business, Energy and Industrial Strategy in the United Kingdom have reported that the UK's highest recording temperatures have transpired in the years since 2002. With over 90% of England homes currently in use of high carbon systems for space heating and domestic hot water. Contributing to increased atmospheric carbon emissions in the dependency on fossil fuel burning; alluding to human-produced atmospheric temperature increase. To help tackle these issues in the residential sector, the capacity of zero-energy technologies has been introduced. Zero-energy implementation has potential to revolutionise the power system, with on-site power generation at the forefront of this. This paper will explore the influence of zero-energy implementation on two UK residential dwellings of disparate locations, using Integrated Environmental Solutions Virtual Environment (IESVE) by focusing on renewable on-site micro-generation systems. The ASHRAE climate zones of Edinburgh and London Gatwick has been selected to examine the performance of the building over varied regional climates of disparate locations. The selected design variables were finally implemented in combination for building simulation in IESVE and compared with a basic model dwelling. The processed simulation results showed a reduction in the buildings energy consumption of 43.4538MWh (71%) for Edinburgh and 33.9929MWh (64%) for London respective to the baseline model. The greatest savings in mitigation of UK climate change can be evaluated in relation to reduction of carbon emissions, which were 7880kgCO2 (46%) and 5423kgCO2 (36%) respectively

COVID 19 And Increased Security Challenges In Northern Nigeria: Interrogating Armed Banditry In Northwestern Nigeria

The COVID 19 pandemic has become a global health issue that now intersects with security issues, especially in African countries. The outbreak of the virus in Africa has halted political, economic and social activities, including countering armed violence. Nigeria is one of the African countries that is faced with security challenges, ranging from Boko Haram insurgency, rural banditry, farmers-herders clash, kidnapping, robbery to piracy among others. However, much attention has concentrated on mitigating the spread of COVID 19 pandemic and the provisions of palliatives to cushion the effects of the abrupt stoppage of formal and informal economic activities. This study examines the intersections between the pandemic and armed banditry in Northwestern. It appears that armed bandits have intensified attacks on communities, against the background of government’s anti-COVID policy. Government has equally re-strategized in responding to the bandits’ attacks. The study gathered data from documented sources and media reports and were analyzed, using content analysis. The study observed that the armed bandits used the COVID 19 lock down policy to increase attacks on some communities, thereby providing a complex dimension to rural banditry in Northwestern Nigeria. This led to increased air and land offensive by the Nigerian military against the bandits. This study recommends among others that government should increase surveillance and adopt strict measures on movements to curtail the activities of the bandit