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Open Access
Absolute Normalization of the Three-Nucleon Transfer Reactions Cross Section in the Distorted-Wave Born Approximation Formalism.
(Obafemi Awolowo University, 1987) Nubi, Olatunbosun Owolabi; Amusa, A.
The three-nucleon transfer reaction cross section form factor for direct pick-up reactions (p,α) and (n,α), using DWBA formalism and shell model basis states, is obtained following an approach analogous to that by Towner and Hardy. Explicit calculations, with gaussian form for the interaction, are performed on the portion of the form factor which depends on the a-particle wave function and on the interaction potential The main emphasis is directed towards carrying out exact calculations that avoids drastic approximations in the two-body interaction potential, and such approximation as the point-alpha approximation and other simplifications of the a-particle wave function as it has been successfully carried out by Amusa for two-nucleon pick-up reactions induced by light ions. Two-body interaction parameters which reproduce low-energy scattering data very well are employed in computing values of the normalization and spectroscopic factors that are extracted from the form factor.
Open Access
Abstracts from the 6th Infection Control Africa Network Congress
(Antimicrobial Resistance and Infection Control, 2016) Wangai, Helen Wambui; Sikhosana, Mpho; Jombwe, Josephat
Infection prevention and control is a set of practices, protocols, and procedures that are put in place to prevent infections that are associated with health care service provision settings. It is an element of quality of care and safety in health care service delivery; health worker occupational health and safety practices; medical waste management; and is also concerned with clinical and public health surveillance and action. Healthcare facilities are ideal settings for the transmission of infections to patients (who are more susceptible), healthcare workers, their families and communities. Healthcare associated infections lead to prolonged hospital stay, increased cost of care and death. Therefore, the objective of this study was to assess infection prevention and control practices in various types and levels of health facilities in Nyandarua County, Kenya. Methodology A cross-sectional descriptive study was conducted in 47 health facilities that were sampled from a total of 153, using cluster sampling technique. The facilities were drawn from public, private and faith based organizations distributed across 5 sub-counties of Nyandarua County, Kenya. Data collection method was purely quantitative using a structured questionnaire. Descriptive analysis was done using SPSS version 17.
Open Access
Acidification Potential in the Nigerian Environment
(1988) Isichei, Augustine O.; Akeredolu, Funso
The inability of developing countries to tackle pollution problems for economic reasons is a fact of life. In addition, due to the lack of knowledge in Nigeria about the environment, it is difficult to ascribe environmental changes to particular factors. Therefore, in viewing acidification caused by sulfur dioxide and oxides of nitrogen in Nigeria, the first problem is to identify the relationship between acidification and prevailing economic activities based on the experience of the developed world.
Open Access
Adoption rate of land clearing techniques and their effects on some soil fertility parameters of an Alfisol in southwestern Nigeria
(African Journal of Agricultural Research, 2010-10-20) Adewole, M. B.; Anyahara, U. C.
effects on some soil fertility parameters of an Alfisol in southwestern Nigeria
Open Access
Adsorption characteristics of green 5-arylaminomethylene pyrimidine- 2,4,6-triones on mild steel surface in acidic medium: Experimental and computational approach
(Elsevier B.V, 2018-01-10) Chandrabhan, Verma; Lukman.O, Olasunkanmi; Eno.E, Ebenso; M.A, Quraishi
The effect of electron withdrawing nitro (–NO2) and electron releasing hydroxyl (–OH) groups on corrosion inhibition potentials of 5-arylaminomethylenepyrimidine-2,4,6-trione (AMP) had been studied. Four AMPs tagged AMP-1, AMP-2, AMP-3 and AMP-4 were studied for their ability to inhibit mild steel corrosion in 1 M HCl using experimental and theoretical methods. Gravimetric results showed that inhibition efficiency of the studied inhibitors increases with increasing concentration. The results further revealed that that electron withdrawing nitro (–NO2) group decreases the inhibition efficiency of AMP, while electron donating hydroxyl (–OH) group increases the inhibition efficiency of AMP. SEM and AFM studies showed that the studied compounds inhibit mild steel corrosion by adsorbing at the metal/electrolyte interface and their adsorption obeyed the Temkin adsorption isotherm. Potentiodynamic polarization study revealed that studied inhibitors act as mixed type inhibitors with predominant effect on cathodic reaction. The inhibitive strength of the compounds might have direct relationship electron donating ability of the molecules as revealed by quantum chemical parameters. The order of interaction energies derived from Monte Carlo simulations is AMP-4 > AMP-3 > AMP-2 > AMP-1, which is in agreement with the order of inhibition efficiencies obtained from experimental measurements.
Open Access
African Greenhouse Gas Emission Inventories and Mitigation Options: Forestry, Land-Use Change, and Agriculture
(Kluwer, 1995) Braatz, B. V.; Brown, S.; Isichei, A. O.; Odada, E. O.; Scholes, R. J.; Sokona, Y.; Drichi, P.; Gastonz, G.; Delmas, R.; Holmes, R.; Amous, S.; Muyungi, R. S.; De Jode, A.; Gibbs, M.
Human-induced change in the composition of the atmosphere seriously threatens the global climate. In an effort to address this threat, 161 nations signed the United Nations Framework Convention on Climate Change at the Earth Summit in Rio de Janeiro in June 1992. The ultimate objective of this international agreement is to achieve stabilization of greenhouse gas concentrations in the atmosphere at a level that would prevent dangerous anthropogenic interference with the climate system. As of the first session of the Conference of the Parties (March/April 1995), 128 nations had ratified the Convention. Parties to the Convention commit to numerous obligations, including commitments to: develop national inventories of anthropogenic emission using agreed, comparable methodologies; and to formulate and implement national programs containing measures to mitigate, and to facilitate adaptation to, climate change. Several bilateral and multilateral programs, including the United States Country Studies Program (U.S. CSP) and the United Nations Environment Programme/Global Environment Facility Country Case Studies Project (UNEP) have been established to provide technical and financial assistance to developing countries and countries with economies in transition in meeting their commitments under the Convention.
Open Access
Allelopathic Effects of Ludwigia decurrens and L.adscendens Subsp. Diffusa on Germination, Seedling Growth and Yield of Corchorus Olitorious L.
(Academic Press, 2010) Sakpere, Ayobola Moninuola; Oziegbe, Matthew; Bilesanmi, Idowu Arinola
This study examined the allelopathic effect of Ludwigia decurrens and L.adscendens exudates on germination, seedling growth (hypocotyl and radicle elongation), seedling mortality vegetative growth and reproductive yield of Corchorus olitorious. Ludwigia decurrens, L. adscendens exudates and tap water (control) were applied to seeds of Corchorus olitorious over a period of 15 days and to 3 weeks old seedling for a period of 4 weeks. Ludwigia exudates had no inhibitory effect on the germination percentage of C. olitorious, but the exudates from the two Ludwigia spp. Induced mortality rate of the 15 day old seedlings (control: 5.00%, L. decurrens: 17.50%, L. adscendens: 26.88%) and a significant decrease in seedling elongation (hypocotyls and radicle length) of C. olitorious. For the vegetative growth experiment, results showed that the stem length, stem fresh weight and leaf area of C.olitorious were significantly inhibited during week 6 (P < 0.05) by L. decurrens and L. adscendens exudates. For reproductive yield experiment, number of pods per plant was significantly reduced on week. The high percentage mortality rate observed in seedlings might be an important factor in reducing seedling survival of Corchorus olitorious in habitats where the two Ludwigia spp are dominant.
Open Access
Analysis of Pesticide Raid® in Feed of Wistar Rat by High-Pressure Liquid Chromatography (HPLC)
(Albert C. Achudume, 2011-12-31) Achudume, Albert C.
The distribution of pesticide by-product in tissues of wistar rats were analyzed using high pressure liquid chromatography. The limit of detection of the HPLC was 0.1 µg. Results show bioaccumulation factor of pesticide “Raid®” in lipid, up to three times that of the feed at the first concentration and gradually decreased as the concentration increased in the muscle > (0.7), brain > (0.5) and liver > (0.3) as indicated in the text. At higher concentration of 961 µg/g, bioaccumulation factor decreased in the lipid to 1.2 and 0.6 in the muscle, 0.03 in the brain and 0.08 in the liver respectively. High Pressure Liquid Chromatography (HPLC) analysis of raid extract suggests the presence of micprothrin and palethrin. The implications are numerous, but simply put that accidental ingestion of chlorinated hydrocarbon as in “Raid®” may involve convulsions, collapse and coma after only brief excitation and ataxia at the onset.
Open Access
An Analysis of Vegetation as a Resource in South-Eastern Nigeria
(1993) Akobundu, I. O. [et al.]
A long-term study was initiated in 1988 in two fallow systems: a planted Dactyladenia (Acioa) barteri system at Mbaise and a natural bush fallow at Umuahia in south-eastern Nigeria. The planted fallow systems consisted of rows of D. barteri spaced 2m apart and lengths of fallow periods ranged from 1 to 3 years. The natural bush fallow periods ranged from 1 to 5 years old. Analysis of the natural bush fallow showed that Dactyladenia barteri, Anthonotha macrophylla and Dialium guineense dominated the vegetation. Stems with a girth of over 20cm contributed most to the stem basal area in the natural bush fallow in all fallow periods. In the planted fallow, a stem basal area of 20 m2/ha was observed only in the 3-year-old fallow. Girth class distribution in the D. barteri field after the second year of fallow was more uniform than in the natural fallow, indicating less interference with the vegetation in the former. For the same fallow length, the amount of litter produced and the nutrient composition were identical in the two systems. Soil analysis showed that pH, soil organic C and total N content in the soil under planted fallow did not change, but extractable P increased with fallow length. The authors concluded that the two fallows systems are potential means of restoring soil fertility through litterfall and pruning application.
Open Access
Antioxidant Activities and Food Value of Five Underutilized Green Leafy Vegetables in South Western Nigeria
(Nigerian Journal of Nutritional Sciences, 2011) Oloyede, F. M; Oloyede, F. A; Obuotor, E. M; Ibironke, S. I.
Objectives: To determine the food value and antioxidant activities of five underutilized leafy vegetables namely: Bidens pilosa L.-Beggar's ticks/ Cobbler's peg; Celosia trigna L.- Woolflower; Crassocephalum crepidioides (Benth) S. Moore – Fireweed/redflower ragleaf; Launaea taracifolia (L.) Cars- Wide lettuce and Solanun nigrum L. - Black Nightshade/sun berry. Materials and methods: Fresh shoots of the five vegetables were collected from the wild, cleaned and milled. Food values which include proximate, minerals, and vitamin C contents were analyzed following the routine chemical analytical methods of Association of Official Analytical Chemists. 1, 1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging effect and phenolic compounds concentrations of the plants extracts were determined spectrophotometrically. Results: The antioxidant activities and nutrient contents of the five vegetables showed variable trends and considerable high values. Across the vegetables, antioxidant activities ranged from 67.2% (L. taracifolia) to 91.8% (B. pilosa) at a concentration of 1mg/ml of the extracted material. The total phenol contents were between 5953.5k1.5 and 10193.5+0.5 mgi100g. The flavonoid contents varieg from 3438±1.00 to 4974±1.00 mg/100g. Anthocyanin content in mg/100g ranged from 0.385±0.005 to 5.065±0.015 while Proanthocyanidin content varied from 0.125±0.05 to 2.050±0.15 in the extract powder. Crude protein values ranged from 3.5 to 9.16g/100g, Carbohydrate contents varied from 1.09 to 9.43g/100g while ascorbic acid(Vitamin C) compositions ranged from 27.2 to 87.3 mgI100g. Ca content ranges from 31.23 to 54.90 mg/100g, while Fe content varied from 21.25 to 139.75 mg/100g. Conclusion: The vegetables contained appreciable quantities of protein, iron, calcium and vitamin C. The antioxidant activities and phenolic antioxidant contents of the vegetables were also high. The health claims associated with some of these food values and bioactive compounds are noteworthy, thereby underlining the potential role of these underutilized vegetables as functional foods.
Open Access
Antiproliferative Activities of Fagara xanthoxyloides and Pseudocedrela kotschyi Against Prostate Cancer Cell Lines
(HHS Public Access, 2015-06-30) KASSIM, OLAKUNLE O.; COPELAND, ROBERT L.; KENGUELE, HILAIRE M.; NEKHAI, SERGEI; AKO-NAI, KWASHIE A.; KANAAN, YASMINE M.
Background/Aim—Roots of Fagara zanthoxyloides and Pseudocedrela kotchyii are used as chewing sticks and as medicinal remedies for diarrhea, cough and fever in West Africa. Extracts of the two plants also possess anti-bacterial, anti-fungal and anti-malarial activities. The aim of the present study was to determine the effects of such extracts on the growth, proliferation and induction of apoptosis in four prostate cancer cell lines. Materials and Methods—Androgen-independent PC3 and DU-145 and androgen-dependent LNCaP and CWR-22 prostate cancer cell lines were cultured for five days with different concentrations of the extracts and examined for growth inhibition and evidence of apoptosis. Results—Irrespective of their androgen dependence, all four cancer cell lines exhibited a dosedependent decrease in cell proliferation and viability by the 3-[4,5-dimethylthiazol-2yl]-2,5diphenyltetrazolium bromide (MTT) assay and in induction of apoptosis. The results also show that LNCap cells were the most sensitive to the two extracts, with highest inhibition at day 3 and exhibiting the highest rate of apoptosis. Conclusion—These observations suggest that F. zanthoxyloides and P. kotchyii could serve as potential chemopreventive agents in the treatment of prostate cancer
Open Access
Application of Numerical Taxonomy to Lip Morphology in the Genus Polystachya Hook (Orchidaceae) in Nigeria
(2009) Folorunso, Abayomi Ezekiel; Jayeola, Adeniyi Akanni
SCLA, a numerical taxonomic method was applied to lip morphology in the genus Polystachya Hook (Orchidaceae) in Nigeria. The basic data matrix was prepared by coding for the presence or absence of the attributes of characters involved. The data were standardized so that the values of a particular character were transformed into values ranging from zero to one. The SCLA showed that the reproductive characters are much better than the vegetative characters earlier used in distribution of Polystachya species into their sections. In the case of reproductive characters, more clusters were reported; this may be an indication of more sections in Polystachya than those earlier reported.
Open Access
Application of Seismic Attributes to Reservoir Evaluation Over "X" Field, Niger Delta, Nigeria
(2015-04-20) Emofo, Godwin Bonny
The aims of this study on the "X" field in Niger Delta were to identify faults and other subsurface structures, to identify and evaluate the tops and bottoms of sand reservoirs and to correlate seismic attributes with reservoir properties determined from well logs. The study also aimed at investigating the petrophysical characteristics of the reservoirs and at generating time and depth structure maps of the study area. These were done to unravel the subsurface geology and hydrocarbon prospect of the study area. The data used for this study included, Migrated 3-D Seismic section [dip and strike], field check shot-survey, composite well logs and base map of "X" Field sourced from Chevron Nigeria Limited (CNL). The Kingdom Suite Software version 7.6 licensed to Department of Geology, Obafemi Awolowo University, lle-lfe. was used for the interpretation of the data and also for detailed fault mapping and correlation of six wells. Gamma-Ray (GR) and Spontaneous Potential (SP) logs were used to identify sand/ shale sequence. Shallow laterolog (LLS) and deep laterolog (LLD) were used to identify the occurrence of hydrocarbons. Neutron and Compensated Formation Density logs were used to define hydrocarbon type present. The identified hydrocarbon-bearing zones G500 and J400 sands were mapped on the seismic section using time-depth data. Time, depth structure and velocity maps were generated for the interpreted events. Selected computed diagnostic seismic attributes and petrophysical characteristics were analysed. The time and depth structure maps revealed that the dominant trapping mechanism in "X" Field was the growth fault generated rollover anticlines which trend northwest-southeast and northeast-southwest of the downthrown side of the main structure building fault F2. The attribute displays showed that the anomaly was directly on the structural closures, thus supporting the interpretation made from the seismic and well log data. Petrophysical values obtained showed that the identified sands had porosity of 23 % in well-01, 18 % in well-03, 20% in TMB-04, 50 % in TMB-05 and 26 % in TMB-06. Water saturation values (SWA) of 62 % were obtained in TMB-01, 93 % in well-03, 53 % in TMB-04, 65 % in TMB-05 and 98 % in TMB-06 and permeability values obtained were in 1.2 Darcy range. The Oil-In-Place (OOIP) in G500 sand was 391,369,882,209 barrels (502,319,971,914.6 M3) and 2,555 680,724.8 barrels (3,280,194,842.98 M3) in J400 sand. Similarly, Gas-In-Place (OGIP) was 2,458,565,805,694 barrels (3,155,548,656,199.72 M3) in G500 sand and 16,0546,57,047.0 barrels (20, 6060, 18,091.16 M3) for J400 sand. In conclusion, Seismic attributes analysis could be used to predict reservoir rock properties, delineate reservoir bodies in a low net-to-gross ratio formation, which led to optimally selected drilling location of wells. Seismic attributes analysis was found to be cost effective and greatly improved reserve estimates. There was a high probability that new locations identified within the seismic grid in "X" Field were viable prospects.
Open Access
Archachatina (Calachatina) Marginata Haemolymph Proteins, Physicochemical Characterization of Protein B.
(Obafemi Awolowo University, 1985) Binutu, Olaoluwa Olujare; Aboderin, A.
The haemolymph of Archachatina (Calachatina) marginata has been found to contain other proteins apart from the predominant protein, haemocyanin. One of the other protein components, Protein B, was isolated and purified using preparatory ultracentrifugation and gel filtration techniques. Physicochemical characterization, employing different techniques has showed that Protein B is different from the haemocyanin (and/or its subunit(s)) from this mollusc. Protein B has a molecular weight of 360KD consisting of two chains which are of identical molecular size. Amino acid composition for Protein B shows that: (i) there exist more acidic residues combined than those of the basic residues combined. (ii) there is a very large occurence of Proline residues (iii) there is also a large amount of cysteine residues. There is one gram atom of copper per dimer. Protein B is a glycoprotein. The carbohydrate portion is made up of units of acetylglucosamine and galactosamine. Peptic peptide fractionation of reduced carboxymethylated Protein B has shown that most of the carbohydrate can be found on a peptide having a mass of 15KD.
Open Access
Aspects of Organic Geochemistry of Shales Associated with the Nigerian Tar Sands.
(Obafemi Awolowo University, 1985) Adedayo, Babatunde Adebayo; Nwachukwu, J. I.
Ten shale samples from three Geological Consultancy Unit, University of Ife, boreholes (Nos. 19, 20 and 25) drilled within the Ondo State tar sand belt were analysed. Bitumen was extracted from all the samples using a standard Soxhiet apparatus. Organic carbon was determined and kerogen isolated from eight samples. Elemental analysis was also carried out on six samples. Organic carbon ranged from 1.6 - 4.9 wt.% and shows that the shales contain adequate organic carbon for source-rocks. The extractable bitumen (SOM) ranged from 1,293 ppm to 28,432 ppm with the aliphatic, aromatic/ester and nitrogen, sulphur and oxygen containing compounds (NS0's) constituting 4 - 340 ppm, 57 - 788 ppm and 631 - 8,879 ppm, respectively of the SOM. Microscopic examination of the kerogen shows that amorphous, herbaceous and coaly organic matter types constitute 53 - 74%, 16 - 41%, and 6 - 21%, respectively. A plot of the hydrogen/carbon and oxygen/carbon atomic ratios on a Van Krevelen diagram indicates that kerogens are types II and III, and are thermally immature. This shows that the shales associated with the tar sands are not the source for the bitumen in the tar sands
Open Access
Assessment of Programmed Cell Death of Aspergillus flavus by Triggered Cysteine-dependent Aspartate-directed Proteases (Meta-caspase3) Lethality Mechanism of Novel Compounds Isolated from Ethyl Acetate Extract of Spondias mombin
(Biochemistry and Modern Applications, 2019-04) Osuntokun, Oludare Temitope; Omotuyi, Olaposi I; Oluduro, Anthonia O; Idowu, Thomas O
Spondias mombin is a plant that has been traditionally noted for its medicinal with a preliminary results report a wide range of antibacterial and antifungal properties. Meta-caspases and Caspases are essential in cells for programmed cell death, in development and most other stages of adult life, and have been termed "executioner" proteins for their roles in the cell. A 12 hours old culture of each microorganism was re-suspended in plant extract at 1000 μg mL in a total volume of 500 μl for 0, 15, 30, 45, 60, and 180 minutes. The cells were pelleted by centrifugation at 5000 g for 5 minutes. The pellets were rinsed twice in phosphate buffer saline (PBS). Then 1/10 volume of 95% ethanol plus 5% saturated phenol were added to the pellets to stabilize cellular RNA. The cells were then re-harvested by centrifugation (8200 g, 4°C and 2 minutes). The supernatant was aspirated and pellets re-suspended in 800 μl of lysis buffer (10 mMTris, adjusted to pH 8.0 with HCl, 1 mM EDTA) and 8.3 U/ml Ready- LyseTM Lysozyme Solution. After the pellets were re-suspended, 80 μl of a 10% SDS solution was added, mixed and incubated for 2 minutes at 64 °C. Then 88 μl of 1 M NaOAc (pH 5.2) was mixed with the lysate followed by an equal volume of water and saturated phenol was added. Total RNA was quantified using Spectrophotometric absorbance at 260 nm DNA was removed with Turbo DNA-free (Ambion, Inc.). Reverse Transcription-PCR reaction was performed in a 15.0 μl final volume (kit number-DNA-PCR739288). Assessment of Polymerase Chain Reaction products (amplicons) were electrophoreses in 0.5% of agarose gel using 0.5 × TBE buffer ( 2.6 g of Tris base, 5 g of Tris boric acid and 2 ml of 0.5M EDTA and adjusted to pH 8.3 with the sodium hydroxide pellet) with 0.5 μl ethidum bromide. The mechanism of action of isolated novel compounds using Metacaspase3 to programme the death of test organism (Aspergillus flavus) between 0 and 180 minutes interval. It was observed that cell (via DNA) were completely destroyed at 180 minutes with all the isolated compounds. The purpose of this research work is to evaluate the programmed cell death (PCD) of Aspergillus flavus by triggered Cysteine-dependent Aspartate-directed proteases (meta-caspase3) lethality mechanism of novel compound isolated from ethyl acetate extract of Spondias mombin.
Open Access
Assessment of the water quality parameters in relation to fish community of Osinmo reservoir, Ejigbo, Osun State, Nigeria
(Research Gate, 2014-04) KOMOLAFE, O.O; ADEDEJI, A.A; FADAIRO, B
Physicochemical indices of water body changed seasonally and this necessitated an investigation to assess the water quality parameters of Osinmo reservoir in relation to its fish species. The water quality parameters were measured using standard methods. Results obtained show that the reservoir is alkaline in nature with dissolved oxygen concentration (1.8-7.2 mgl-1) and alkalinity (64 CaCO3 mgl-1-108 CaCO3 mgl-1) which were within the optimum range for growth and survival of fish. Four families of fish comprising eight species were encountered. The sex-ratio of five species which were statistically different (P<0.05) indicated reproductive efficiency populations while other fish species whose sex-ratio differed insignificantly (P>0.05) revealed a growing population. The well-being of the fish species was adequate as observed in the least mean condition factor of 0.666±0.057 in C. gariepinus and the highest mean of 2.000±0.242 in S. galilaeus. The productivity of the reservoir can be improved through proper management of the water body
Open Access
Assessment of the water quality parameters in relation to fish community of Osinmo reservoir, Ejigbo, Osun State, Nigeria
(2014-10-14) KOMOLAFE, O.O; ADEDEJI, A.A; FADAIRO, B
Physicochemical indices of water body changed seasonally and this necessitated an investigation to assess the water quality parameters of Osinmo reservoir in relation to its fish species. The water quality parameters were measured using standard methods. Results obtained show that the reservoir is alkaline in nature with dissolved oxygen concentration (1.8-7.2 mgl-1) and alkalinity (64 CaCO3 mgl-1-108 CaCO3 mgl-1) which were within the optimum range for growth and survival of fish. Four families of fish comprising eight species were encountered. The sex-ratio of five species which were statistically different (P<0.05) indicated reproductive efficiency populations while other fish species whose sex-ratio differed insignificantly (P>0.05) revealed a growing population. The well-being of the fish species was adequate as observed in the least mean condition factor of 0.666±0.057 in C. gariepinus and the highest mean of 2.000±0.242 in S. galilaeus. The productivity of the reservoir can be improved through proper management of the water body
Open Access
An assessment on DNA microarray and sequence-based methods for the characterization of methicillin-susceptible Staphylococcus aureus from Nigeria
( Frontiers in Microbiology, 2015-10-20) Shittu, Adebayo O; Oyedara, Omotayo; Onko, Kenneth; Raji, Adeola; Peters, Georg; Müller, Lutz von; Schaumburg, Frieder; Herrmann, Mathias; Rufﬁng, Ulla
Staphylococcus aureus is an important human pathogen causing nosocomial and community-acquired infections worldwide. In the characterization of this opportunistic pathogen, DNA microarray hybridization technique is used as an alternative to sequence based genotyping to obtain a comprehensive assessment on the virulence, resistance determinants, and population structure. The objective of this study was to characterize a deﬁned collection of S. aureus isolates from Nigeria using the microarray technique, and to assess the extent that it correlates with sequence-based genotyping methods. The clonal diversity and genomic content of 52 methicillin-susceptible Staphylococcus aureus (MSSA)wereinvestigatedby spa typing,MLSTandDNAmicroarrayhybridization. More than half (55.8%) of these isolates were associated with clonal complexes (CCs) typically associated with methicillin-resistant S. aureus (MRSA) clones i.e., CC1, CC5, CC8,CC30,andCC45.Certaingeneslinkedwithvirulence(hlgAandclfA)andadherence (ebpS, fnbA, sspA, sspB, and sspP) were detected in all isolates. A number of genes or gene clusters were associated with distinct clonal types. The enterotoxin gene cluster (egc) was linked with CC5, CC25, CC30, CC45, and CC121, enterotoxin H gene (seh) with CC1, exfoliative toxin D gene (etd) with CC25 and CC80, and the epidermal cell differentiation inhibitor B gene (edinB) with CC25, CC80, and CC152. The excellent agreement between data from DNA microarray and MLST in the delineation of Nigerian MSSA isolates indicates that the microarray technique is a useful tool to provide information on antibiotic resistance, clonal diversity and virulence factors associated with infection and disease.
Open Access
ATR-FTIR AND HPLC SPECTROSCOPIC STUDIES AND EVALUATION OF MINERAL CONTENT OF CARICA PAPAYA LEAVES AND FLOWERS
(Open Access Scientific Publisher, 2015-02-06) Fadare, O.A.; Durosinmi, O.M.; Fadare, R.; Izevbekhai, O.U.; Awonyemi, I.O.; Obafemi, C.A.
We applied Fourier transform infrared spectroscopy (FTIR) to study the main constituents in the male Carica papaya leaves and flowers in the mid infrared region 4000–650 cm –1. The findings indicated that FTIR spectrum can discriminate and identify various functional groups present in the pawpaw parts. Four water-soluble vitamins, thiamine (vitamin B 1 ), riboflavin (vitamin B 2 ) niacin (vitamin B3) and folic acid (vitamin B9) were analyzed by HPLC. Niacin and folic acid were detected in the leaves at a concentration of 7.08 mg/100 g and 1.00 mg/100 g dry weight, respectively, while only folic acid could be detected in the flowers at a high concentration of 510.34 mg/100 g dry weight. Atomic absorption spectroscopy (AAS) analysis of the samples showed that the leaves and flowers contain elements like K, Na, Mn, Mg, Fe, Zn, Cu, Ca, Cd and Ni in various proportions, with the leaves containing higher concentrations of Mg, Ca, Zn, Fe and Ni than the flowers.