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Abstract

Zinc phosphodiesterase (ZiPD) participates in the maturation of tRNA precursors. The roles of metal ions in promoting phosphoryl transfer reaction on zinc phosphodiesterase (ZiPD) activity have not been fully characterized. Therefore, this study investigated the effects of some metal ions on phosphodiesterase activity of Escherichia coli ZiPD as well as the binding site and binding affinity of the metal ions. ZiPD activity was measured by monitoring the rate of hydrolysis of bis-para-nitrophenyl phosphate (bis-pNPP) in the presence of some selected divalent metal ions (Mn2+, Co2+, Mg2+ and Zn2+). The results obtained revealed that Mn2+ at 1 mM activated ZiPD activity by 4-fold with binding affinity score of 1.795. Co2+ at 0.5 mM activated ZiPD activity by 2-fold with binding affinity score of 1.773. Mg2+ at 0.5 mM enhanced the binding affinity of ZiPD for bis-pNPP but did not increase the turnover rate of ZiPD. Zn2+ at 1.5 mM activated ZiPD activity by 2-fold via increased affinity of ZiPD for bis-pNPP. In conclusion, the findings from this study showed that Mn2+ and Zn2+ are the most effective stimulatory ions of ZiPD for bis-pNPP while Zn2+ exerted the highest binding affinity of ZiPD for bis-pNPP.

Abstract

In an effort at developing new filters and bio-packaging materials with antibacterial properties, nanocomposite fluorescence films of cellulose acetate reinforced with cellulose nanoparticles, methylcellulose nanoparticles, propylcellulose nanoparticles, toluene diisocyanate modified cellulose and cellulose acetate nanoparticles were prepared and characterized. The effects of the nanoparticles on the mechanical, crystallinity and morphology of the nanocomposite films was studied. The sensitivity of bacteria against the new nanocomposite films was experimented. Scanning electron microscopy showed the films to be well dispersed. Modulus increase was directly proportional to nanoparticle loading. Samples with maximum compatibility were cellulose nanoparticles (CNPs) loading of 40% with modulus of 113.3Mpa and toluene diisocyanate modified cellulose nanoparticles (TDI-CNPs) at 20% loading had 146.0Mpa. Others include cellulose acetate nanoparticles (CANPs) at 30% loading with 73.0Mpa; methylcellulose acetate nanoparticles (MCNPs) with 5% loading had a modulus of 87.3Mpa and pure cellulose acetate had 45.0Mpa. The films were applied as filters for the removal of cells of Bacillus; Enterococcus and Micrococcus sp. from the crude bacteriocin, with recoverability of 95.9% based on the bacteriocin produced. The films showed limited antibacterial properties against clinical Pseudomonas sp 1, Pseudomonas sp 2 and Proteus sp. It is concluded that the films showed limited antibacterial properties hence it has antibacterial potentials and capabilities.

Abstract

The opening of mitochondrial permeability transition (mPT) pore is a well recognized important event in the execution of mitochondrial-mediated apoptosis. Some bioactive compounds induce apoptosis in tumour cells via the induction of mPT pore opening. This study therefore investigated the effect of 3-Para-fluorobenzoyl-propionic acid (3PFBPA), a metabolite of haloperidol on mPT pore, mitochondrial ATPase activity (mATPase), mitochondrial lipid peroxidation (mLPO) and cytochrome c release (CCR). Thirty-two male Wistar rats, were acclimatized for 14 days in clean cages. After 30 days of treatment, they were sacrificed and the liver mitochondria isolated using differential centrifugation. The mPT pore, mATPase, mLPO and CCR were determined by standard methods using a spectrophotometer. The mPT pore opening was induced by 3PFBPA by 1.4, 3.6, 5.6, 6.6 and 7.4 folds, when compared with the control. Also, there was release of cytochrome c and enhancement of mATPase activity by 3PFBPA. The results also show that 3PFBPA reduced lipid peroxidation. However, oral administration of 3PFBPA at 50, 100 and 200 mg/kg did not have any effect on mPT pore opening and mATPase activity when compared with the control but there was inhibition of mLPO. These findings suggested the pharmacological potential of 3PFBPA against the pathological processes related to insufficient apoptosis (based on the in vitro data) and oxidative stress due to its anti-lipidperoxidative effect.

Abstract

Tiger nut is a plant generally underutilized in many parts of the world where it grows mostly as a weed. It is loved by children and many adults for its milky sugary taste, without most consumers being aware of its nutritional and health benefits. The level of awareness on the importance of this wonderful and greatly enriched plant is indeed very low. This review is aimed at expounding some of the advanced scientific researches which authenticated the folk reports on the therapeutic potential of the plant. Research findings which present potential application of this wonderful plant in food industry, pharmaceutical formulation, agricultural production and biofuel generation are also elucidated.

Abstract

The ingestion of aluminum from food containers such as cookware, cans, utensils and wrappings and its subsequent release into the environment is a growing public health concern. Aluminum is widely used in manufacturing cookware due to its malleability, high heat conductivity, light weight, durability, availability and affordability. This paper therefore gives a review of most relevant literatures on the benefits and risks of the various types of aluminum cookware in use, the composition and the public health effects of aluminum ingestion. Studies that reported the leaching of aluminum from cookware into food and environmental effects of aluminum leaching were also reviewed. In the developing countries, aluminum cookwares are produced from scrap metals and has been reported to leach harmful substances including heavy metals such as: nickel, arsenic, copper, cadmium, lead, and aluminum into cooked food. Several factors have been reported to increase the rate of leaching of metals from aluminum cookwares. Exposure to metals from aluminum cookware and the public health effects have not been well studied, hence, our recommendation for more studies to elucidate the health effect of this practice. This review also presents measures that can limit exposure to the risks that may arise from the use of aluminum cookware.

Abstract

The volume of pharmaceuticals discharged into the environment increases daily as a consequence of human life. In the present study, the seasonal variation of ibuprofen in sediment, biota, water, and their exposure risk were investigated in River Owena and Ogbese, Nigeria. The high-performance liquid chromatography coupled to a mass spectrometer (HPLC-MS/MS) was used to analyze the samples after clean up and pre-concentration by solid-phase extraction. The mean concentration of IBU in the samples spanned a range of 1.75 - 2.75 μg/g in sediment, 0.01 – 15.00 μg/g in fish, and 0.00002 – 0.005 μg/ml in water. The measurement of IBU in the sediment and water was significantly elevated in the dry season than the wet season, whereas the opposite was the case in biota. There was a significant interaction between season, media, and rivers with respect to IBU occurrence in the sampled rivers. The calculated bio-water accumulation factor (BWAF) was as high as 750,000 μg/g in fish, proving IBU is extremely bio-accumulative. The ecotoxicological risk assessment for average and worst possible outcome showed that the risk quotient (RQ) for IBU present in the water was sufficient to cause toxicity to fish in both freshwater bodies. The potential bioavailability of IBU to aquatic fauna for prolonged periods spanning several months can result in its circling back into the food web afterward. The baseline info provided by this study in these freshwaters may provide valuable information for the implementation of safety limits for the management of IBU influx into the environment.

Abstract

The combination of antiretroviral (ARV) drugs: lamivudine, tenofovir disoproxil fumarate (TDF) and efavirenz is among the preferred first-line regimens for adolescents and adults infected with HIV. However, knowledge on in vivo genetic and reproductive toxicity of each of these drugs and their combination is limited. We evaluated the genotoxicity of lamivudine, TDF, efavirenz and their combination utilizing the mouse micronucleus (MN) and sperm morphology tests. Histopathological analysis of the testes of exposed mice was also carried out. 0.016, 0.032, 0.064 and 0.129 mg/kg bwt of lamivudine, TDF and the combination; and 0.032, 0.064, 0.129 and 0.259 mg/kg bwt of efavirenz corresponding to 0.125, 0.250, 0.500 and 1.000 x the human therapeutic daily dose (HTD) of each of the ARVs and their combinations were administered to mice for 5 consecutive days. Data on MN showed a significant increase (p ---lt--- 0.05) across the tested doses of TDF, efavirenz and the combination, with the combination inducing lower frequency of MN than TDF and efavirenz. Lamivudine did not evoke significant induction of MN. Significant increase in frequency of abnormal sperm cells were observed in the tested samples, however, the combination induced the highest number of abnormal spermatozoa. The ARVs and their combination induced pathological lesions such as vacuolation and necrosis in mice testes. These findings suggest that the individual ARVs and their combination are potentially capable of activating genetic alterations in the bone marrow and germ cells of male mice thereby raising concern for long term use by HIV patients.

Abstract

This paper assessed in-vehicle and ambient pollution levels from vehicles along Ilorin-Lagos highway covering three distinct 3-hour periods (morning, afternoon and evening) of the day (from 7.30 am to 6.30 pm) along with reported health challenges at six (6) settlements (SP1-SP6) that covered four (4) states. In the case of ambient pollution, Gilair-3 air sampler (GAS) was used to measure sulphur (iv) oxide, (SO2) while ALTAIR 5x Multi-gas Detector (AMD) was used to measure both carbon (ii) oxide, (CO) and sulphur (iv) oxide, (SO2) for all scenarios. Vehicular volume was manually conducted to determine the number of vehicles. Questionnaire was used to assess information on the health challenges faced by the commuters. The concentrations of SO2 ranged from 0.142 - 0.550 ppm (ambient) and 0.037 - 0.097 ppm (in vehicle) using AMD and GAS respectively while CO concentration was between 2.289 - 18.055 ppm using AMD. The results for the in- vehicular pollution revealed that the concentration levels obtained for CO and SO2 inside the vehicles were 6.32 ppm and 0.126 ppm under opened-window condition and 9.53 ppm and 0.274 ppm under closed-window condition respectively (without air condition). The SO2 concentrations obtained from both ambient and in-vehicle were found to be much higher when compared with the FEPA standards; SO2 (0.01 – 0.1 ppm), USEPA standards; SO2 (0.075 ppm) while the CO level obtained from in-vehicle under the two scenarios (opened and closed windows) were below the limit of NESREA standards (10 – 20 ppm) and USEPA standards (35 ppm). Having noticed that these pollutants act under different environmental conditions, the work established statistical evidence that traffic volume affected the pollutants concentrations at most of the sampling points and that the higher the traffic, the higher the emissions and the more the risk of health challenges.

Abstract

Studies reveal that not up to 50% of earthworm species have been described in the world and the understanding of earthworm diversity is finite in most countries including Nigeria. The study was aimed at evaluating the diversity of earthworms and environmental factors affecting their abundance. Earthworms were collected from three (3) different sampling locations in Nnamdi Azikiwe University, Awka. Descriptive statistics and estimation of species abundance, dominance and diversity were used to analyze the data obtained from the study. From the study, four (4) species of earthworms were identified and recorded from the three sampling locations. Eudrilus eugeniae (54.9%) was the most abundant species followed by Hyperidrilus africanus (20.3%), Libyodrilus violaceous (19.6%) and Alma millsoni (6.3%) with the least abundant species. The result of the diversity indices showed Science village (1.13) as the most diverse habitat followed by Emelda hostel (0.86) and Boys’ hostel (0.84) with the least diversity of species. Soil pH ranged from 2.25 to 4.06 and total organic matter ranged from 14.10 to 16.36%. Soil temperature was uniform with an average value of 27°C for the three sampling locations. The soil moisture content ranged from 11.19 to 14.12%. The conductivity recorded the lowest value (25.60μS/cm) in Emelda Hostel and highest value (111.8 μS/cm) in Science village. The study provided understanding into the patterns of earthworm populations in Nnamdi Azikiwe University, Awka and the need for the conservation of earthworm diversity. Better understanding about habitat and living conditions of earthworms is required to provide suitable and enhanced production of vermicompost in different geographic conditions.

Abstract

In this treatise, we examined the activities of researchers of Nigeria descent in the frontier areas of nanoscience and nanotechnology, with a focus on green nanotechnology. The exploration of literature published by scholars were reviewed and compartmentalized on the basis of applications of the nanomaterials. It can be concluded that the level of activities in this area is expanding owing to the emergence of more published works since the beginning of 2010. However, in comparison with research outputs from other developing African countries such as South Africa and Egypt, activities in green nanotechnology are still at low ebb in Nigeria. Issues that are contributory to the slow pace were identified and appropriate solutions in terms of improved funding of education, enactment of national policy on nanotechnology, curriculum development, international cooperation as well as human resource development among others were discussed.