ghanaopendata/ghanaian-research-english huggingface dataset:
Characterization and Evaluation of Zeolite A/Fe3O4 Nanocomposite as a Potential Adsorbent for Removal of Organic Molecules from Wastewater

In this work, zeolite (Z) and Z-Fe3O4 nanocomposite (Z-Fe3O4 NC) have been synthesized. The Fe3O4 nanoparticles were synthesized using the extract from maize leaves and ferric and ferrous chloride salts and encapsulated into the zeolite framework. The nanocomposite (Z-Fe3O4 NC) was characterized using X-ray diffractometer (XRD), Fourier-transform infrared (FT-IR) spectroscopy, energy-dispersive X-ray (EDX) spectroscopy, and scanning electron microscopy (SEM). The potential of Z-Fe3O4 NC as an adsorbent for removing methylene blue molecules (MB) from solution was examined using UV-Vis and kinetic and equilibrium isotherm models. The adsorption data fitted best with the pseudo-second-order model and Weber and Morris model, indicating that the adsorption process was chemisorption, while the Weber and Morris described the rate-controlling steps. The intraparticle diffusion model suggests that the adsorption processes were pore and surface diffusion controlled. The Langmuir isotherm model best describes the adsorption process indicating homogeneous monolayer coverage of MB molecules onto the surface of the Z-Fe3O4 NC. The maximum Langmuir adsorption capacity was 2.57 mg/g at 25°C. The maximum adsorption efficiency was 97.5%. After regeneration, the maximum adsorption efficiency achieved at a pH of 7 was 82.6%.

Source: UG
Characterization of 2 Human Genotype G10 Rotavirus Strains, 3008CM and 1784/CI/1999, Isolated in Cameroon and Cote d’Ivoire during the 1999–2000 Rotavirus Season

The main research focus of the Electron Microscopy and Histopathology Department in the past 20 years has been in the areas of enteric diarrhoeas with special emphasis on rotavirus. Through its diarrhoea surveillance studies, the Department has helped to firmly establish rotaviruses as a major cause of diarrhoea in children, and document the circulation of unusual rotavirus genotypes in Ghana. The Department has also recently expanded its diagnostic repertoire to include the identification and characterization of noroviruses, astroviruses, and other enteric viruses.

Source: UG
Characterization of a mutant population of cocoyam (Xanthosoma sagittifolium L. Schott)

A mutant population of cocoyam (Xanthosoma sagittifolium L. Schott) developed through gamma irradiation of shoot tips of cocoyam was evaluated in two field experiments. In the first experiment, four putative mutants, fifty irradiated clones and four non-irradiated clones were evaluated for morpho-agronomic diversity. Progeny derived from minisetts were characterised in a second experiment to establish repeatability of the distinctive characters of the putative mutants. Yields were exceptionally low and this was attributed to poor environmental conditions. The mutants showed a distinctive yellow cormel apex and yellow interior cormel colour. Out of seventeen morphological traits studied in the second experiment, ten were monomorphic. These were growth habit, petiole attachment, petiole surface glaucous, leaf pubescence, leaf variegation, leaf surface glossy (shining), leaf margin, number of collecting vein, position of collecting vein and shape of petiole in cross-section. The seven polymorphic traits were petiole colour, colour of vein on leaf surface, leaf shape, leaf margin colour, leaf surface colour, leaf sinus denuding and lamina orientation. The main differences in the polymorphic characters were between the mutants on one side and the irradiated (non mutants) and non-irradiated clones on another side. It will be interesting to determine whether the mutants have desirable agronomic characters. © 2006 Asian Network for Scientific Information.

Source: UG
Characterization of a Novel Plasmodium Falciparum Merozoite Surface Antigen and Potential Vaccine Target

Introduction: Detailed analyses of genetic diversity, antigenic variability, protein localization and immunological responses are vital for the prioritization of novel malaria vaccine candidates. Comprehensive approaches to determine the most appropriate antigen variants needed to provide broad protection are challenging and consequently rarely undertaken. Methods: Here, we characterized PF3D7_1136200, which we named Asparagine-Rich Merozoite Antigen (ARMA) based on the analysis of its sequence, localization and immunogenicity. We analyzed IgG and IgM responses against the common variants of ARMA in independent prospective cohort studies in Burkina Faso (N = 228), Kenya (N = 252) and Mali (N = 195) using a custom microarray, Div-KILCHIP. Results: We found a marked population structure between parasites from Africa and Asia. African isolates shared 34 common haplotypes, including a dominant pair although the overall selection pressure was directional (Tajima’s D = -2.57; Fu and Li’s F = -9.69; P < 0.02). ARMA was localized to the merozoite surface, IgG antibodies induced Fc-mediated degranulation of natural killer cells and strongly inhibited parasite growth in vitro. We found profound serological diversity, but IgG and IgM responses were highly correlated and a hierarchical clustering analysis identified only three major serogroups. Protective IgG and IgM antibodies appeared to target both cross-reactive and distinct epitopes across variants. However, combinations of IgG and IgM antibodies against selected variants were associated with complete protection against clinical episodes of malaria. Discussion: Our systematic strategy exploits genomic data to deduce the handful of antigen variants with the strongest potential to induce broad protection and may be broadly applicable to other complex pathogens for which effective vaccines remain elusive.

Source: UG
Characterization of a secretase activity which releases angiotensin-converting enzyme from the membrane

Angiotensin-converting enzyme (ACE; EC 3.4.1.15.1) exists in both membrane-bound and soluble forms. Phase separation in Triton X-114 and a competitive e.l.i.s.a. have been employed to characterize the activity which post-translationally converts the amphipathic, membrane-bound form of ACE in pig kidney microvilli into a hydrophilic, soluble form. This secretase activity was enriched to a similar extent as other microvillar membrane proteins, was tightly membrane-associated, being resistant to extensive washing of the microvillar membranes with 0.5 M NaCl, and displayed a pH optimum of 8.4. The ACE secretase was not affected by inhibitors of serine-, thiol- or aspartic-proteases, nor by reducing agents or alpha 2-macroglobulin. The metal chelators, EDTA and 1,10-phenanthroline, inhibited the secretase activity, with, in the case of EDTA, an inhibitor concentration of 2.5 mM causing 50% inhibition. In contrast, EGTA inhibited the secretase by a maximum of 15% at a concentration of 10 mM. The inhibition of EDTA was reactivated substantially (83%) by Mg2+ ions, and partially (34% and 29%) by Zn2+ and Mn2+ ions respectively. This EDTA-sensitive secretase activity was also present in microsomal membranes prepared from pig lung and testis, and from human lung and placenta, but was absent from human kidney and human and pig intestinal brush-border membranes. The form of ACE released from the microvillar membrane by the secretase co-migrated on SDS/PAGE with ACE purified from pig plasma, thus the action and location of the secretase would be consistent with it possibly having a role in the post-translational proteolytic cleavage of membrane-bound ACE to generate the soluble form found in blood, amniotic fluid, seminal plasma and other body fluids

Source: UG
Characterization of Anopheles gambiae s.l. and insecticide resistance profile relative to physicochemical properties of breeding habitats within Accra Metropolis, Ghana

Malaria is endemic in Ghana as in most countries of sub-Saharan Africa. This study was conducted to characterize Anopheles gambiae s.l. and determine pyrethroid resistance profiles relative to physicochemical properties of breeding habitats in Accra, Ghana. Eight aquatic habitats containing Anopheles larvae were identified and from each habitat, larvae and water were sampled. Adult An. gambiae reared from larvae were morphologically identified and tested for permethrin (0.75%) and deltamethrin (0.05%) resistance using WHO bioassay method. An. gambiae s.s. found were identified to their molecular levels and kdr mutation detected using PCR-based methods. Twenty-nine physicochemical parameters of each water sample were measured and their levels connected with pyrethroid resistance and proportions of An. gambiae s.s. molecular forms in habitats. A total of 2,257 mosquitoes were morphologically identified as An. gambiae s.l. and all 224 processed for PCR were identified as An. gambiae s.s., of which 56.46% and 43.54% were M and S-forms, respectively. Both forms occurred in sympatry in all larval habitats and no S/M hybrids were detected. However, M-form larvae were in high proportion in polluted habitats than the S-form. An. gambiae s.s. was highly resistant to both deltamethrin and permethrin with mortality rates of 42.98-70.0% and 6.5-20.0% respectively. The frequency of kdr mutation was 60.5% (n=195). This mutation occurred in both S and M-forms, but was mainly associated with the S-form (X 2=10.92, df =1, P=0.001). Carbonate and pH were both selected in discriminant function analysis as best predictors of high proportion of M-form in the habitats. The adaptation of An. gambiae s.s. in polluted aquatic habitats coupled with occurrence of insecticide resistance is quite alarming particularly for urban malaria control and needs further exploration in a wider context.

Source: UG
Characterization of anti-EBA175RIII-V in asymptomatic adults and children living in communities in the Greater Accra Region of Ghana with varying malaria transmission intensities

The Department of Immunology conducts research in the field of immunology of infectious and non-infectious diseases. The Department has the overall goal of contributing knowledge to better diagnosis, management, control and prevention of infectious and non-infectious diseases in Ghana and worldwide. This is consistent with the overall strategy of the Noguchi Memorial Institute for Medical Research (NMIMR) and in line with the strategy of the College of Health Sciences of the University of Ghana.

Source: UG
Characterization of Cassava Fiber of Different Genotypes as a Potential Reinforcement Biomaterial for Possible Tissue Engineering Composite Scaffold Application

Cassava bagasse contains considerable amount of natural single elementary cellulose fibers and white thick root fiber (thick-core fiber) that has seen frequent application in the packaging industry as reinforcement for plastic composite development. However, a review of the literature was unable to find any study that characterized the material properties (such as tensile properties) of both the single elementary and white thick-core cassava cellulose fibers), and their application as potential reinforced filler in tissue engineering scaffold development. In this study, the tensile properties, morphology, crystallinity and thermal degradation profile of non-chemically treated single elementary cellulose fibers and thick-core fibers of different cassava genotypes were investigated. Fibers were tested according to ASTM C1557 under direct tension in a standard mechanical testing system and the cross-sectional area of the fractured regions of the fibers were determined using a 3D optical microscopy method. Cassava fibers of different genotypes did not show any significant difference in tensile properties, with average tensile strength ranging from (5.1–7.3 MPa), Young’s modulus (258–333 MPa) and failure strain (3.4–4.2 %). Tensile test conducted for several gage lengths did not influence the tensile strength and Young’s modulus of the fibers, however, strain-at-break depended on gage length. Single elementary and thick-core fibers showed similar surface morphology, degree of crystallinity (ranging from 21–40 %) and tensile properties with some variation in elastic modulus. Cassava fibers are thermally stable around 100–200 oC, where processing could be performed. Preliminary results showed an improvement in the mechanical properties of a gelatin scaffold when cassava cellulose microfibers were used as reinforcing fillers. The current findings show that cassava fiber has a reasonable mechanical strength, stiffness and thermal stability, and could be considered as a reinforced biomaterial to improve the mechanical integrity of tissue engineering scaffolds. © 2019, The Korean Fiber Society.

Source: UG
Characterization of Cassava Fibre for Potential Wound Dressing Application

Wound dressing is the application of a sterile pad to protect a wound from further harm and promote healing. Over the past decades, various materials including calcium alginate, hydrogel, hydrocolloid and gauze based wound dressing materials have been developed. Unfortunately, shortcomings such as potential allergic reaction, high cost, short shelf life and scarcity have been associated with their use. In developing countries such as Ghana, sterilized gauze is commonly used in wound dressing but it causes scar formation and traumatic pain during removal. In addressing the issues of cost and availability, there may be local materials like cassava (Manihot esculenta) with the ability to aid in wound healing. Cassava is a cheap staple crop grown in Africa which is rich in carbohydrate, fibre and minerals. This research characterized three genotypes of cassava (IITA-TMS-GAEC-160006 (IT6), IITA-TMS-GAEC-160004 (IT4) and Afisiafi (Afi)). These genotypes have been studied in terms of their fibre content, fluid absorption capacity, hemolytic ability and their ability to promote rapid blood coagulation (coagulation time). Fibre samples were soaked in deionized (DI) water and PBS (Phosphate buffered saline) and at different time intervals the swollen samples were weighed. Fibre samples were also brought into contact with human blood and toxicity of samples determined. The results reveal that the rate of absorption of fluid by fibres in both DI water and PBS ranges between 0.66-0.93 g/min and fibres are generally non-toxic to blood cells. The fibre properties were compared with gauze and from these, some genotypes of cassava fibre were recommended for further research towards the design of a wound dressing material.

Source: UG
Characterization of charcoal and firewood ash for use in African peri‑urban agriculture

Background: Ample quantities of ashes generated from domestic biomass energy combustion in Ghanaian kitchens are currently disposed of despite their potential agricultural value. This study aimed to investigate the potential agricultural value of charcoal and firewood ashes in terms of differences in the chemical and mineralogical compositions, and to identify the suitability of aqua regia, H2SO4, vinegar and distilled water to extract plant nutrients (Ca, Mg, K, Na, and P). The chemical compositions were determined by atomic absorption spectrometry after extractions with aqua regia, H2SO4, vinegar and distilled water while mineralogy was determined by X-ray powder diffraction. Results: The charcoal ash had 0.2 units, 13 ds m−1, and 7% higher (P < 0.05) pH, EC, and CCE, respectively, than the firewood ash, whereas the latter had 6, 17, 43, and 139 μg g−1 higher (P < 0.05) As, Cu, Mg, and Zn contents, respectively, and more minerals with 86% being Mg-rich. Calcite and calcium oxide were the dominant minerals occurring in both ashes followed by calcium manganate ( CaMnO3). Aqua regia and vinegar were suitable for Ca, acidic solutions for Mg, H2SO4 and aqua regia for P with Na and K being virtually soluble in all solutions. Lead, Mn, Ni, and Zn had values in the order of hundreds. Conclusions: Although the ashes differ, they both contain trace elements whose bioavailability may differ and may not necessarily lead to plant uptake after field application. This offers an opportunity for further research into the threshold trace element contents of wood ash and their relationship with plant uptake in different soil pH and soil types.

Source: UG
Characterization of chemical composition and anti-nutritional factors in seven species within the Ghanaian yam (dioscorea) germplasm

This study characterized the most cultivated and consumed yam (Dioscorea) cultivars within the Ghanaian yam germplasm based on their chemical composition and anti-nutritional factors. Matured yam cultivars grown under the same climatic and edaphic factors were harvested from the Roots and Tuber Conservatory Division of the Council for Scientific and Industrial Research-Plant Genetic Resources Research Institute, Bunso Ghana. Samples were analyzed for proximate composition, mineral content and levels of tannins, phytates and oxalates using standard analytical methods. Significant differences (p<0.05) existed between the means of the yam varieties based on their chemical characteristics. The moisture content of the fresh tubers ranged between 58.18 to 77.79%. The varieties had low fat (<1.0%), protein (4.0-6.5%) and fibre (1.25-3.47%) with high carbohydrate (77.5-87.3%) and energy (1451.2-1574.7 kJ/100g). The most predominant minerals were potassium (475-1475 mg/100g), phosphorus (158-294.5 mg/100g) and sodium (62.5-102.5 mg/100g). All the studied varieties had low levels of oxalates, tannins and phytates (<15 mg/100g) and could all be safely recommended for food processing applications. D. rotundata, D. praehensalis, D. cayenensis and D. bulbifera differed from the rest by having higher levels of carbohydrate and energy with appreciable levels of minerals that make them nutritious and can be used as reliable food and energy security crops. D. rotundata (Pona) variety distinguishes itself because of low moisture content (high dry matter) that makes it suitable for high yield flour production.

Source: UG
Characterization of Chitosan/ Zeolite drug delivery composite and curcumin release kinetics in a simulated pH environment

Cancer remains a formidable global health challenge, necessitating innovative strategies for effective drug delivery to tumor sites. This study is focused on modeling the release profile of a chitosan/zeolite nanocomposite beads delivery system encapsulating curcumin. The nano composites were synthesized by functionalizing zeolite with chitosan and subsequently loading curcumin. The chitosan/zeolite nanocomposite was characterized for its physicochemical prop erties, including surface morphology, functional groups, elemental profile, crystal structure, and drug loading capacity using SEM, FTIR, EDS, XRD, and UV–vis spectrophotometer respectively. In vitro experiments investigated the release kinetics of curcumin from the composite in simulated pH environments, providing insights into the drug release behavior. The chitosan/zeolite nano composite demonstrated a controlled, and sustained release of curcumin, exhibiting significant potential for optimizing therapeutic outcomes. The maximum entrapment efficiency of the chi tosan/zeolite drug delivery vehicle was recorded at 84 %, indicating high efficiency in encap sulating drug molecules. Drug release kinetics were analysed using the Higuchi, Korsmeyer Peppas, Zero-Order, First-Order, and Hixson-Crowell models. The Higuchi kinetic model, which explains the release rate of drugs from an insoluble matrix based on Fickian diffusion, best explained the release of curcumin, with a correlation coefficient of R2 = 0.9351. These results indicate that the zeolite functionalized chitosan nanocomposite beads hold promise as a viable platform for enhanced drug delivery, enabling prolonged drug circulation and improved thera

Source: UG
Characterization of Common Bean (Phaseolus vulgaris L.) Genotypes for Drought Tolerance

Background: Drought is a major constraint affecting the seed yield of common bean in smallholder farmers’ fields in Malawi. Therefore, there is a need to develop genotypes that can perform well under drought conditions. The study was conducted to assess the variability of common bean genotypes under stressed and optimum soil moisture conditions. Methods: Forty-three common bean genotypes were evaluated under low and optimum soil moisture in a split-plot pot experiment in 2017. Data were collected at flowering stage on five root traits and seed weight. Result: Highly significant (P<0.01) differences were observed among the genotypes and the genotype  water treatment interactions for the root traits and seed weight. Water stress increased hypocotyl root number, basal root number and basal root growth angle by 127.1, 11.3 and 46.1%, respectively, while hypocotyl root length, basal root whorl number and seed weight were reduced by 7.1, 1.9 and 9.4%, respectively. Broad-sense heritability and genetic advance (%) were highest for hypocotyl root length. Genotypes CER-78, SAB-560 and SER-125 were considered tolerant to soil moisture stress and should therefore be tested in various drought conditions for release and used for genetic enhancement, focusing on root traits and seed yield.

Source: UG
Characterization of conserved T- and B-cell epitopes in plasmodium falciparum major merozoite surface protein 1

Vaccines for P. falciparum will need to contain both T, and B-cell epitopes. Conserved epitopes are the most desirable, but they are often poorly immunogenic. The major merozoite surface protein 1 (MSP-1) is currently a leading vaccine candidate antigen. In this study, six peptides from conserved or partly conserved regions of MSP-1 were evaluated for immunogenicity in B10 congenic mice. Following immunization with the peptides, murine T cells were tested for the ability to proliferate in vitro and antibody responses to MSP-1 were evaluated in vivo. The results showed that one highly conserved sequence (MSP-11, VTHESYQELVKKLEALEDAV; located at amino acid positions 20 to 39) and one partly conserved sequence (MSP-123, GLFHKEKMIL NEEEITTKGA; located at positions 44 to 63) contained both T- and B-cell epitopes. Immunization of mice with these peptides resulted in T-cell proliferation and enhanced production of antibody to MSP-1 upon exposure to merozoites. MSP-11 stimulated T-cell responses in three of the six strains of mice evaluated, whereas MSP-123 was immunogenic in only one strain. Immunization with the other four peptides resulted in T-cell responses to the peptides, but none of the resulting peptide-specific T cells recognized native MSP-1. These results demonstrate that two sequences located in the N terminus of MSP-1 can induce T- and B-cell responses following immunization in a murine model. Clearly, these sequences merit further consideration for inclusion in a vaccine for malaria.

Source: UG
Characterization of edible soldier fly protein and hydrolysate altered by multiple-frequency ultrasound: Structural, physical, and functional attributes

The effect of conventional (control), and different ultrasonic treatment modes (fixed, and sweep frequency ultrasound) on structural, physical and functional traits of soldier fly (Hermetia illucens) larvae protein preparations and hydrolysates were examined. Ultrasonication significantly increased lightness (L*) of protein isolates by x 7.46 % compared to control. Sonic-treated (particularly sweep-type) isolates and hydrolysates showed significant increases in thiol value, reconstitutability function (pH 2–10), and surface charge; and significant decreases in turbidity, and particle size, relative to controls. Protein isolates were characterized by higher molecular weight (MW) using SDS-PAGE, whereas hydrolysates were lower (with no observable variances). By numerical estimation, hydrolysates (especially the sweep-treated) showed significantly lower MW (< 1000 Da). Deconvoluted FTIR spectra (α-helix, β–sheet/turn, random coil fractions), and UV spectra analyses showed differences in samples. Treatment type (sweep/ fixed frequency ultrasound) could be used to alter protein structure, modify functionality, and thereby usage of H. illucens protein/hydrolysate preparations.

Source: UG