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Abstract

Malaria and toxoplasmosis are two important parasitic diseases with significant public health concerns in the Sub-Saharan African countries. Some aspects of pathogenesis of the two parasitic diseases involve the central nervous system manifesting neuropsychiatric disorders. Studies have implicated the single infection by Plasmodium spp. and Toxoplasma gondii in development of psychosis. Although concomitant infection of the two parasites suggests an aggravated psychotic condition, there is currently no reported study. This article reviewed some studies which implicated malaria and toxoplasmosis in psychosis. It further explored the likely role of concurrent infection by the parasites on psychosis, the dynamics of their pathology and possible effects of certain psychosis-associated cytokines and other biomolecules on the central nervous system. We recommend evidence-based research efforts in this field for the effective management of these two parasitic diseases to abate the public health burden of psychosis.

Abstract

Acalypha wilkesiana is a tropical herb used for the treatment of skin disorders. Phytochemical studies carried out on the pulverized dried leaves of the plant revealed the presence of alkaloids, cardiac glycosides, anthraquinones, saponins, flavonoids and tannins. The crude 50% methanol extract obtained from the dried leaves was sequentially partitioned into three fractions. Thin layer chromatography of the fractions revealed three (3) components each in hexane fraction; ethyl acetate fraction and butanol fraction of the plant extract. Column chromatography of the fractions was carried out. The infrared analyses of the components revealed the presence of alkenes, hydroxyl group, conjugate carbonyls, esters in the hexane fraction components. Those from the ethyl acetate and butanol fractions contained aliphatic amides or amines with carbonyl and esters attached in the two fractions. Essential oil was extracted from the dried leaves using hydro-distillation method. GC-MS analysis of the essential oil revealed the presence of major compounds which included: n-Hexadecanoic acid 4-Hexen-2-one-3-methyl, Pyrrole and 6-Benzamido-4-benzoyl-1,2,4-triazine-3,5. The presence of the functional groups inferred from IR and GC-MS analyses with the antimicrobial potential of the essential oil may support the use of the plant in the management of skin infections, gastrointestinal disorders and other ailments.

Abstract

Working with subsurface engineering problems in Hydrocarbon exploration as regard rock elastic and petrophysical properties necessitate accurate determination of in-situ physical properties. Several techniques have been adopted in correlating log-derived parameters with petrophysical and mechanical behavior of the rocks. However, limited field applications show there are no particular parameters and correlations that are generally acceptable due to the regional variation in geologic features (i.e., degree of mineralogy, texture, etc.). This study presents a method that assesses the disparity in petrophysical properties of oil and gas reservoir rocks in relation to their elastic/mechanical properties from 10 well-logs and 3D migrated seismic data. Two distinct facies were identified from seismic data after computing attributes. Reflection strength attribute of 2.5 and above depicts Bright spots within the central section of the field as clearly revealed by Variance and Chaos attributes. Formation properties calculated from logs were conformally gridded in consonance with the reflection patterns from the seismic data. The average Brittleness index (BI) of 0.52 corresponds to Young’s modulus (E) values of between 8 and 16 for the dense portion. This portion is the laminated, reasonably parallel, and undeformed part, flanked by the unlaminated and chaotic zones. From cross plots, the distinguished lower portion on the plot is the segment with higher sand of more than 50 %. This segment corresponds to the reservoir in this study as confirmed from the genetic algorithm neural network Acoustic impedance inversion process result. Similarly, the plot of Compressional velocity (Vp) and Poisson’s ratio (ν), reveals the laminated sand value of not less than 0.32 of ν, and Vp of about 4.2 km/s. The average porosity is about 16 %, average water saturation is about 16 %, and average permeability is approximately 25 md. Rock properties trends in a unique pattern and showing fluctuation that confirms the compressive nature of the structure with corresponding petrophysical properties. This trend is sustained in permeability computed and suggests a significant gravity-assisted compaction trend and fluid movement. It gives a reasonable idea of the fluid movement interplay and mechanical property variation within the sequence and across the dome. This part probably has been subjected to fair compressional deformational forces initiated from outside the survey.

Abstract

The occurrence of erythromycin resistance in bacteria causing respiratory tract infections varies among populations and is associated with inappropriate antibiotic usage. This study was undertaken to determine erythromycin resistance in bacterial isolates from patients with respiratory tract infections in Ikere-Ekiti. Bacteria were isolated from sputum specimens using standard microbiological protocols while the antibiotic susceptibility pattern of isolates was determined using the Kirby-Bauer method. Erythromycin resistance genes: mefA, ermA, and ermB were detected using multiplex polymerase chain reaction (PCR). Out of the 157 bacterial isolates identified using standard microbiological methods, Klebsiella spp. 40 (25%) was the most frequent followed by Staphylococcus aureus 34 (22%) and Proteus spp. 34 (22%) while Streptococcus spp., Escherichia coli, and Bacillus spp. had 19 (12%), 20 (13%), and 10 (6%) respectively. Most of the bacterial isolates were resistant to penicillin 148 (94%), cloxacillin 147 (93.6%), amoxicillin-clavulanic acid 141 (90%), erythromycin 141 (90%), and tetracycline 124 (79%). However, the isolates were least resistant to trimethoprim-sulfamethoxazole 57 (36%). Out of the 48 bacterial isolates investigated using multiplex PCR amplification for erythromycin resistance genes, 10 (20.8%) were positive for mefA, 3 (6.3%) were positive for ermA, and 2 (4.2%) were positive for ermB. The association between the presence of mefA, ermA, and ermB genes and erythromycin resistance was not significant (p=0.464). The presence of erythromycin resistant genes in pathogenic bacterial isolates from the respiratory tract was revealed in this study. Awareness of the risk of self-medication and abuse of antibiotics should be emphasized.

Abstract

Hermannia geniculata is a herb that plays an important role in the treatment of an array of diseases including diabetes, ulcer, and colitis in the South African traditional medicine. The bioactive constituent and medicinal properties in phenols of Hermannia geniculata (PoHG) roots were investigated using high pressure thin layer chromatography (HPTLC). The α-amylase inhibitory potentials of PoHG was determined by reacting different concentration of the plant extract with 1% starch solution containing α-amylase. The inhibitory effect of the extract on α-glucosidase was evaluated by pre-incubating α-glucosidase with varying extract concentrations followed by the addition of ρ -nitrophenylglucopyranoside.. The reactive oxygen and free radical scavenging potentials of the extract were also analyzed. The result showed the presence of phenolic compounds in the extract with retention factor (Rf) values ranging from 0.14 to 095. The extract scavenged DPPH, ABTS+, hydroxyl, and superoxide anion radicals. The extract was able to chelate metallic ions with a lower IC50 value which differs significantly (p≤0.05) from silymarin. Moreover, PoHG extract inhibited the key enzymes (α-glucosidase and α-amylase) involved in carbohydrate catabolism with IC50 values of 1.76 ±0.14 and 7.52 ±0.23 mg/mL respectively while IC50 value reported for acarbose were 7.62 ±0.12 and 4.38 ±0.25 mg/mL for glucosidase and α-amylase, respectively. The α-glucosidase exhibited non-competitive inhibition by PoHG extract while α-amylase showed uncompetitive inhibition. This study confirmed the presence of phenol in PoHG extract and also showed an appreciable antioxidant and antidiabetic activities in vitro. Therefore, PoHG extract may be of nutraceutical importance.

Abstract

Access to potable water is a major problem confronting most developing nations particularly with the overwhelming health burden posed by polluted water and its sources. In this review, studies on the level of contamination of drinking water sources in different geopolitical zones in Nigeria were assessed. The anthropogenic activities eliciting the pollutions were extensively discussed. Overall, the level of Nigeria preparedness in meeting the sustainable development goal number 6 (SDG no 6: to ensure availability and sustainable management of water and sanitation for all) was evaluated. Cogent methods that could enhance the achievement of SDG no. 6 were suggested. From our analysis of published literature, pre- and post- SDG implementation in Nigeria, it is clear that no significant progress has been made in providing potable water for all in Nigeria. All implementing partners must therefore rejig the process to ensure the availability of potable water, in order to achieve the sustainable development goal six.

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 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 < 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.