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Antisickling Effects of Quercetin may be Associated with Modulation of Deoxyhaemoglobin, 2, 3-bisphosphoglycerate mutase, Redox Homeostasis and Alteration of Functional Chemistry in Human Sickle Erythrocytes.

Abstract

It is now glaring that sickle cell anaemia is still one of the highest leading inbred hemoglobinopathy amongst Africans. This study examined the antisickling effects of quercetin via modulation of deoxy-haemoglobin, redox homeostasis and alteration of functional chemistry in human sickle erythrocyte using in silico and in vitro models while espousing preventive and curative approaches. Quercetin was docked against deoxy-haemoglobin and 2, 3-bisphosphoglycerate mutase, with binding energies (−30.427 and −21.106 kcal/mol) and Ki of 0.988μM and 0.992μM at their catalytic sites via strong hydrophobic and hydrogen bond interactions. Induction of sickling was done using 2% metabisulphite at 3h. Treatment with quercetin prevented sickling outstandingly at 5.0μg/mL and reversed same at 7.5μg/mL, 83.6% and 75.9%, respectively. Quercetin also significantly (P<0.05) maintained the integrity of erythrocyte membrane apparently from the observed % haemolysis relative to untreated. Quercetin significantly (P<0.05) prevented and counteracted lipid peroxidation while stimulating GSH and CAT levels which were detected to considerably (P<0.05) increase with simultaneous significant (P<0.05) reduction in SOD level based on curative approach. Umpiring from our FTIR results, a favorable alteration in the part of functional chemistry in terms of shifts (bend and stretches) and functional groups were observed relative to the induced erythrocyte/untreated. Thus, antisickling effects of quercetin may be associated with modulation of deoxy-haemoglobin, redox homeostasis and alteration of functional chemistry in human sickle erythrocytes.

Open access
A Coupled Insulin and Meal Effect Neuro-Fuzzy Model for The Prediction of Blood Glucose Level in Type 1 Diabetes Mellitus Patients.

Abstract

Diabetes Mellitus is a metabolic disorder that affects the ability of the human body to properly utilize and regulate glucose. It is pervasive world-wide yet tenuous and costly to manage. Diabetes Mellitus is also difficult to model because it is nonlinear, dynamic and laden with mostly patient specific uncertainties. A neuro-fuzzy model for the prediction of blood glucose level in Type 1 diabetic patients using coupled insulin and meal effects is developed. This study establishes that the necessary and sufficient conditions to predict blood glucose level in a Type 1 diabetes mellitus patient are: knowledge of the patient’s insulin effects and meal effects under diverse metabolic scenarios and the transparent coupling of the insulin and meal effects. The neuro-fuzzy models were trained with data collected from a single Type 1 diabetic patient covering a period of two months. Clarke’s Error Grid Analysis (CEGA) of the model shows that 87.5% of the predictions fall into region A, while the remaining 12.5% of the predictions fall into region B within a four (4) hour prediction window. The model reveals significant variation in insulin and glucose responses as the Body Mass Index (BMI) of the patient changes.

Open access
Escherichia coli as Possible Agents of Spread of Multidrug Resistance in Port Harcourt, Rivers State.

Abstract

Multidrug resistance (MDR) continues to be a growing global issue. The problem of MDR is fuelled in part by the spread of the genes encoding resistance horizontally which is linked particularly to conjugation involving plasmids. Studies have demonstrated the presence of plasmids in drug resistant isolates, few have shown a link between these plasmids and drug resistance via plasmid curing especially in our locale. This study set out to explore this link in Escherichia coli isolates from Port Harcourt, Nigeria. Plasmid curing was done on a selection of clinical and non-clinical bacteria using acridine orange and antibiotic susceptibility testing carried out on both cured and uncured variants. Data generated was analysed to ascertain the multiple antibiotic resistance (MAR) index and MDR of each isolate. Data was then compared to ascertain effects of plasmid curing on antibiotic resistance of the isolates. Results revealed a decrease in resistance to 7 of 8 antibiotics following plasmid curing. The highest change was noted in ceftazidime (40%), followed by ofloxacin (26.7%). Plasmid curing caused a shift in MAR index values of isolates from higher to lower indices. At MAR index values of ≤0.25 occurrence increased from 5% to 36.7% while at MAR index values ≥0.75, occurrence reduced from 29.9% to 10.0%. A reduction in the degree of MDR was noted (from 55% to 36.7%). Strikingly, the reduction in MDR level of non-clinical isolates was 30% as opposed to 3.4% in the clinical isolates. This study shows a link between plasmids and antibiotic resistance. For the non-clinical isolates, the high-level link between MDR and plasmid carriage could indicate a higher use of antimicrobials in non-clinical rather than clinical settings. Additionally, it could be an indicator for a higher risk of the transfer of MDR determinants from non-clinical sources to human populations in our locale.

Open access
Influence of the Techniques and Degrees of Ripeness on the Nutritional Qualities and Carotenoid Profiles of Tomatoes (Solanum lycopersicum).

Abstract

Tomato is a significant vegetable crop with numerous health benefits derived from its carotenoids, flavonoids and other phytonutrients contents. This work studies the nutritional qualities and carotenoids contents of five different cultivars of tomatoes (San Marz, Nasmata, Roma VF, Ogbomoso local and 4-lobes). The variations of pH, titratable acidity, reducing sugar, total solid, lycopene and beta-carotene contents of these tomatoes were investigated under ambient temperature and field ripening techniques and the mean values of these parameters investigated at different ripening stages and techniques were compared. Lycopene contents were significantly higher (p < 0.05) in tomatoes subjected to field ripening compared with those ripened under ambient temperature. The highest lycopene content (17.18 μg/g) was observed in Roma VF cultivar at fully-ripe stage under field ripening technique while the lowest value (0.64 μg/g) was in 4-lobes cultivar at semi-ripe stage under ambient temperature ripening. Similar trend was observed in the variation of betacarotene (a pro-Vitamin A index) among the tomato cultivars. The evaluated reducing sugar contents (ranging from 1.84 to 5.23 μg/g) were significantly higher (p < 0.05) in fully-ripe tomatoes compared to semi-ripe ones under field ripening and the trend was reversed for some cultivars under ambient temperature ripening. The titratable acidities of the tomatoes were significantly higher at the semi-ripe stage (0.24 to 0.38 %) under field ripening than those obtained under ambient temperature ripening (0.15 to 0.25 %). The pH of the tomatoes ranged from 3.58 to 4.07 and 3.46 to 5.40 under field and ambient temperature ripening, respectively, and the higher pH values obtained under ambient temperature ripening condition could make such tomatoes unsuitable in tomato processing plants. Consumption of tomatoes for the purpose of dietary antioxidant lycopene and pro-Vitamin A could maximally be achieved at fully-ripe stage under field ripening condition.

Open access
Studies on Tursiops truncatus and Stenella coeruleoalba Dolphin Species: from Retinal Cell Morphological Comparisons Towards its Surrounding environment.

Abstract

In this current study, the retinal cell morphology of two dolphin species, Tursiops truncatus and Stenella coeruleoalba was compared, and supplemented with a miniature review of how it relates to surrounding environment. Retinal cell morphology involved sectioning and retino-separation of eyes, morphometric analysis of retinal cell layers and its corresponding neurons, followed by stratigraphy of both retina and area/density of ganglion neuron cell bodies. A qualification criteria was developed to describe both thickness and visibility. To relate with surrounding environment of studied species, we searched relevant synthesized literature combining such key words as ‘dolphin’, ‘Tursiops truncatus’, ‘Stenella coeruleoalba’, ‘eye’, ‘vision’, ‘ecology’ and ‘environment’. Retinal cell morphology comparisons showed that the thickness of outer nuclear layer had upper (37.8 – 38.5 μm) whereas outer plexiform layer had lower (7.8 – 8.7 μm) range values, with some differences between individual retinal layers (p<0.05) but specific to some cases. Area of ganglion cell layer of multipolar neurons of retina of both studied species could surpass the 800 μm2 mark, which suggests the presence of ‘giant’ size cell types. Plausibly, the retino-morphological comparisons of studied dolphin species depict the context of micro-view, and able to relate with a macro-view with respect to its surrounding environment.

Open access
Vulnerability Assessment: A Geospatial Bio-accessibility Approach Using Polycyclic Aromatic Hydrocarbons Concentration of Soils in Lagos, Nigeria.

Abstract

Cancer is on the increase globally. Cancer could be associated with hazards from anthropogenic activities. This study attempted to determine the site-specific potential human risks from polycyclic aromatic hydrocarbons (PAHs) in sites of different socioeconomic human activities from soils across Lagos metropolis in Nigeria by including a geographic information system (GIS) approach. A Human Simulation Test method was used to determine bio-accessibility for 16 priority PAHs. This was then spatially modelled using a GIS. The spatial vulnerability index for cancer developed show some variation within the study area from 0.2 – 0.0002 all falling below the normal exposure risk level of 1.0. The vulnerability to cancer based on different anthropogenic activities assessed were within the acceptable risk levels. However, it is important to reduce human exposure to even low concentrations of bio-accessible PAHs due to their tendency to bio-accumulate in plants, humans and other organisms.

Open access
Assessment of Environmental Factors on Secondary Metabolites and Toxicological Effects of Datura metel Leaves Extracts

Abstract

This study evaluated the chemical composition, physicochemical properties, toxicological and environmental potentials of the Datura metel (D. metel) leaves extracts. Fresh leaves of D. metel were harvested at three different times of the day (morning, afternoon and evening), extraction done in succession using n-hexane and ethanol solvents respectively. Preliminary phytochemical screening, physicochemical analysis for specific gravity, pH, colour, total ash and moisture contents of the dried extracts were determined. The characterisation of the bioactive compounds using Gas Chromatography-Mass Spectrometry, showed the presence of different compounds at the three different times of the day, out of which phytol and 9,12,15-octadecatrienoic acid were present at all times. These results confirmed that some bioactive compounds present in this plant are dependent on environmental factor , time of harvest and the choice of solvent used while the presence of others are independent on these factors. Each extract was administered orally to Wistar rats for two weeks. There were significant difference (p < 0.05) in activities of AST (serum and heart), ALT (liver and serum) and ALP (Serum, liver and kidney), as well as the concentrations of albumin and protein in the liver and serum and urea in the serum of experimental rats given n-hexane and ethanolic extracts of D. metel. Generally it also suggest that the leaf extracts collected at three different times of the day had some significant toxicological effect, thus may not be totally safe for consumption at the dosage indicated since tissues membranes integrity of the Wistar rats were not potentially preserved.

Open access
Assessment of the flocculating potentials of Alcaligenes faecalis Isolated from the Estuary of Sodwana Bay

Abstract

Alcaligenes faecalis was previously isolated from Sodwana Bay, South Africa and was shown to be a bioflocculant producing microorganism. The bioflocculant production potential was further assessed through the optimization of the standardized culture media. The production of biofloculant as well as the flocculation was evaluated using different variables such as the size of inoculum, sources of carbon and nitrogen, time course and pH. Through optimization A. faecalis showed an improvement in the production of its bioflocculant and also flocculating activity for the following factors: flocculating activity of 71% for an inoculum size of 1%. The bioflocculant produced when maltose was used as source of carbon, showed flocculating activity of 91%, urea, as the most efficient nitrogen source, showed a flocculating activity of 97%, the optimum pH was 9. The time courses analysis between 60 and 72 hours showed the peak for flocculation and by implication highest level of bioflocculant production.

Open access
Qualitative Detection and Isolation of Bacteria from Surfaces of Canned Drinks Sold in Ugbor, Benin City

Abstract

The qualitative assessment of putative bacterial pathogens on the surfaces of canned drinks sold in Benin metropolis was evaluated in this study. Standard bacteriological culture-based techniques employing the use of selective and differential media (Oxoid) such as Bacillus cereus agar, mannitol Salt agar, Pseudomonas cetrimide agar, bile esculin agar and MacConkey agar were used for isolation and identification of bacteria from swabbed surfaces of canned drinks. Kirby-Bauer disc diffusion technique was used for antibacterial susceptibility testing. The multiple antibiotic resistance (MAR) index was deduced from the antibiogram characterization to evaluate the public health importance of the bacterial isolates. Refrigerated samples had 25% contamination while 75% were not contaminated and about 15.39% contamination was observed for non-refrigerated samples (stored in crates or cartons) compared to the counterpart 84.61%. The bacterial species include Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli, Bacillus cereus, Bacillus sp. and Enterococcus sp. The bacteria were found to be sensitive to ciprofloxacin (92.5%) and gentamicin (90.1%) and least susceptible to cefixime (23.1%) and vancomycin (26.4%). They were found to be multi-resistant because they have an MAR index above the tolerable permissible limit (0.2) for common antibiotics usually used for their eradication. It is important to ensure that the surfaces of canned drinks must be rinsed with water before consumption.

Open access
Evaluation of Some Salicylaldehyde-derived Baylis-Hillman Adducts and Coumarin Derivatives as Potential Antisickling Compounds

Abstract

Some salicylaldehyde-derived Baylis-Hillman adducts and 3-(chloromethyl)coumarins have been synthesised and evaluated in vitro for their antisickling activities. The compounds were screened for inhibitory and reversal activity against mutated haemoglobin (HbSS) in red blood cells at four different concentrations (4 mg/mL, 2 mg/mL, 1 mg/mL and 0.5 mg/mL) as a measure of their antisickling potentials. Among the synthesized compounds, 6-chloro-3-(chloromethyl)coumarin 4d showed the highest inhibitory activity (83.75±1.90%), followed by 6-chlorocoumarin-3-methylsulfinic acid 5d (80.90 ±0.91%) and the least was tert-butyl-3-hydroxy- 3-(2-hydroxyphenyl)-2-methylenepropanoate 3a (33.33±1.86%). The results obtained from the reversal antisickling experiment showed that the percentage of sickle cells able to revert to the normal biconcave shape was dose dependent. Compound 5d had the highest reversal activity (66.49±1.39%) followed by 6-bromo-3- (chloromethyl)coumarin 4c (59.66±2.95) and 4d (55.50±1.95%) at 4 mg/mL. Compound 4c had higher reversal activity than the standard p-hydroxybenzoic acid at 2 mg/mL, 1 mg/mL and at 0.5 mg/mL. The 3-substituted coumarins 4a-d, and 5d had higher inhibitory antisickling activities than their Baylis-Hillman precursors 3a-d. Effect of 4a-d and 5d on the rate of polymerization of sickle cell heamoglobin was further studied spectrophotomerically using hemolysate of HbSS. The considerable inhibitory and reversal activities of these compounds make them good candidates for further antisickling studies.

Open access