ghanaopendata/ghanaian-research-english huggingface dataset:
Antiplasmodial activity and cytochrome p450 mediated pharmacokinetic drug interactions of xylopic acid

acid (XA), the major constituent of the fruit of Xylopia aethiopica has shown several pharmacological properties. Consequently, the fruit is being used in the preparation of food. Traditionally, the plant is used to treat several diseases and it has been formulated into a nasal drop despite the lack of information about its safety, food-drug interaction, and other pharmacokinetic properties. Therefore, this study investigated the antiplasmodial effect of XA on P. falciparum, and its effect on rat liver CYP enzymes in vivo and in vitro. To establish the effect of XA on P. falciparum, the parasite strain Dd2 was cultured and treated with XA. Pentobarbitone-induced sleeping time was used to investigate the effect of XA on rat liver enzymes. Inhibition or induction of some isoforms of CYP450, CYP 1A1/1A2, 1A2, 2B1/2B2, 3A4, 2D6 and 2C9 was investigated using microsomal fractions of rat liver. The in vitro inhibition of selected CYP (1A2, 3A4) was assessed by treating rat liver microsomes XA. Results obtained showed that Xylopic acid exhibited negligible antiplasmodial activity. The IC50 of XA > 20 μM. Xylopic acid induced CYP 1A1/1A2, 1A2, 2D6, 2C9, and inhibited CYP3A4, 2B1/2B2. The findings would help mitigate toxicity and therapeutic failure especially in cases of co-administration of medications with food containing XA, with metabolism altered by the latter

Source: UCC
Antiplasmodial activity of extracts of tridax procumbens and phyllanthus amarus in in vitro plasmodium falciparum culture systems

Background: Aqueous extracts of Tridax procumbens (TP) (Compositae) and Phyllanthus amarus (PA) (Euphorbiaceae) are used in traditional medicine in Ghana to treat malaria. Previous studies have demonstrated the anti-trypanosoma, anti-bacterial and anti-HIV effects of TP and PA. Objective: To assess the antiplasmodial activity of extracts of TP and PA. Method: Aqueous extracts of TP and PA were prepared. A portion of each was freeze-dried and the remaining extracted sequentially with ethyl acetate and chloroform. Ethanolic extracts were also prepared. The antiplasmodial activity of the extracts was assessed with the 3H-hypoxanthine assay using chloroquine resistant (Dd2) Plasmodium falciparum parasites. Chloroquine was used as the reference drug. The modified tetrazolium-based colorimetric assay was also used to evaluate the red blood cell (RBC)- protective/antiplasmodial activities and cytotoxicities of the extracts. Results: Results showed that TP and PA have antiplasmodial activities. The aqueous and ethanolic extracts of PA were the most active, yielding EC50 values of 34.9μg/ml and 31.2μg/ml, respectively in the tetrazolium-based assay. The TP and PA produced and IC50 values of 24.8μg/ml and 11.7μg/ml, respectively in the hypoxanthine assay. Protection of human RBCs against P. falciparum damage by the extracts highly correlated with their antiplasmodial activities. None of the extracts, within the concentration range (1.9- 500μg/ml) studied produced any overt toxicity to human RBCs. Conclusion: The results indicate that both PA and TP have activities against chloroquine-resistant P. falciparum (Dd2) parasites. The antiplasmodial principles extracted into water and ethanol but not chloroform or ethyl acetate

Source: UCC
Antiplasmodial and Antipyretic Activity and Safety Evaluation of the Methanolic Leaf Extract of Murraya exotica (L.)

The increasing mortality and morbidity of malaria in Africa coupled with the recent reports of antimalarial drug resistance reinforces the need for novel antimalarial agents from natural plant products with folkloric use for the disease. Murraya exotica (L.) (Rutaceae) is widely used as an ornamental plant used indigenously to treat fever, cough, and infectious wounds and eliminate pain from injury and trauma. This study was conducted to evaluate extracts of the leaves of Murraya exotica (L.) (Rutaceae) for its safety and antipyretic and antimalarial activity in rodent models. Method. In this study, the Peters 4-day suppressive and curative test in Plasmodium berghei-infected mice was used to demonstrate the antiplasmodial activity of the methanolic leaf extract of Murraya exotica (L.) (MEE). The study also evaluated the subacute toxicity study and the antipyretic activity of MEE on baker’s yeast-induced hyperthermia in rodent models. Results. Murraya exotica (L.) extract demonstrated curative antimalarial activity, with a percentage suppression of 45.84, 64:32 ± 0:33, 56:74 ± 2:16, and 64:61 ± 0:67 at doses of 50, 100, 300, and 600 mg/kg, respectively. In the Peters 4-day suppressive test, MEE at dose 600 mg/kg had the highest chemosuppression (76:02 ± 1:38%) compared with artesunate (2 mg/kg, p.o.) (82:56 ± 0:97%). Subacute oral toxicity studies in Sprague-Dawley rats documented no deaths, with no significant changes in clinical signs, organ weights, and hematological and biochemical parameters. The LD50 of MEE was estimated to be above 1000 mg/kg in Sprague-Dawley rats. All doses of MEE and paracetamol reduced pyrexia in 1 h and 2 h after their administration. The percentage reduction of rectal temperature (TR) for the positive control (paracetamol, 150 mg/kg, p.o.) was 44.36% while the Murraya exotica extract at doses 50 mg/kg, 100 mg/kg, 300 mg/kg, and 600 mg/kg recorded 67.74%, 40.78%, 66.42%, and 59.42%, respectively. Murraya exotica at dose 100 mg/kg exhibited significant reduction (p < 0:05) in baker’s yeast-induced pyrexia. Conclusions. The findings in this study show the antipyretic, curative, and suppressive antiplasmodial activity as well as the safety of the methanolic leaf extract of Murraya exotica (L.) supporting its traditional use for malaria and fever.

Source: UCC
The Antiproliferative Effect of Palm Oil Gamma-Tocotrienol on Isoprenoid Pathway of Hepatoma Cell Line

1) European Journal of Scientific Research is an international official journal publishing high quality research papers, reviews, and short communications in the fields of biology, chemistry, physics, environmental sciences, mathematics, geology, engineering, computer science, social sciences, medicine, industrial, and all other applied and theoretical sciences. The journal welcomes submission of articles through ejsr@eurojournals.com.

Source: UCC
Antithrombotic Therapy and Prevention of Thrombosis, 9th ed: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines

pharmacokinetics and pharmacodynamics of oral anticoagulant drugs that are currently available for clinical use and other aspects related to their management. Methods: We carried out a standard review of published articles focusing on the laboratory and clinical characteristics of the vitamin K antagonists; the direct thrombin inhibitor, dabigatran etexilate; and the direct factor Xa inhibitor, rivaroxaban. Results: The antithrombotic effect of each oral anticoagulant drug, the interactions, and the monitoring of anticoagulation intensity are described in detail and discussed without providing specific recommendations. Moreover, we describe and discuss the clinical applications and optimal dosages of oral anticoagulant therapies, practical issues related to their initiation and monitoring, adverse events such as bleeding and other potential side effects, and available strategies for reversal. Conclusions: There is a large amount of evidence on laboratory and clinical characteristics of vitamin K antagonists. A growing body of evidence is becoming available on the first new oral anticoagulant drugs available for clinical use, dabigatran and rivaroxaban.

Source: UCC
Anti‑allodynic and Anti‑hyperalgesic effects of an ethanolic extract and xylopic acid from the fruits of Xylopia aethiopica in murine models of neuropathic pain

Background: Fruit extracts of Xylopia aethiopica are used traditionally in the management of pain disorders including headache and neuralgia. An animal model of vincristine‑induced sensory neuropathy was developed after repeated intraperitoneal injection in rats and used in the present work to study the effects of the ethanolic extract of X. aethiopica (XAE) and its diterpene xylopic acid (XA) in vincristine‑induced neuropathic pain. Materials and Methods: Vincristine (0.1 mg kg‑1 day‑1) was administered during two cycles of five consecutive days to induce chemotherapy‑induced neuropathic pain. Static tactile anti‑allodynic, anti‑hyperalgesic, and cold anti‑allodynic effects of XAE (30‑300 mg kg‑1) and XA (10‑100 mg kg‑1) were assessed using Von Frey filaments of bending forces of 4, 8, and 15 g, the Randall‑Selitto paw pressure test, and cold water (4.5°C), respectively. Results: Administration of vincristine caused the development of allodynia and hyperalgesia with no significant motor deficit, spontaneous pain, and foot deformity. XAE (30‑300 mg kg‑1) and XA (10‑100 mg kg‑1) exhibited anti‑hyperalgesic, tactile, and cold anti‑allodynic properties with XA exhibiting greater potency than XAE. Pregabalin (10‑100 mg kg‑1) used as control produced similar effect. Conclusion: These findings establish the anti‑allodynic and anti‑hyperalgesic effects of the ethanolic fruit XAE and its major diterpene XA in vincristine‑induced neuropathtic pain.

Source: UCC
Anxiety and Depression among HIV Patients of the Infectious Disease Department of Conakry University Hospital in 2018

Anxiety and depression continue to be significant comorbidities for people with human immunodeficiency virus (HIV) infection. The aim of this study was to determine the prevalence of anxiety and depression disorder among HIV patients at Conakry, Guinea. In this cross-sectional study, we described socio-demographic, clinical and psychosocial data related to anxiety and depression in 160 HIV patients of the University Teaching Hospital, Conakry, Guinea. The Hospital Anxiety and Depression Scale (HADS) was used for measuring depression and anxiety in the prior month. The HADS score of ⩾8 was used to identify possible cases of depression and anxiety. Multivariate logistic regression analyses were performed to identify factors associated with symptoms of anxiety and depression. The prevalence of comorbid depression and anxiety among HIV patients was 8.1% and the prevalence of anxiety and depressive symptoms among HIV-infected patients was 13.8% and 16.9%, respectively. Multivariate analysis showed that individuals having BMI ⩽ 18 (AOR = 3.62, 95% confidence interval (CI) 1.37–9.57) and who did not receive antiretroviral treatment (AOR = 18.93, 95% CI 1.88–188.81) were significantly more likely to have depressive symptoms. Similarly, having age <40 years (AOR = 2.81, 95% CI 1.04–7.58) was also significantly associated with anxiety. Prevalence of symptoms of anxiety and depression was high in these HIV patients. This suggests a need for training on the screening and management of anxiety and depression among HIV patients.

Source: UCC
Anxiolytic and Antidepressant Effects of Maerua angolensis DC. Stem Bark Extract in Mice

The stembark extract of Maerua angolensis DC. (Capparaceae) is used as a traditional remedy for management of anxiety, psychosis, and epilepsy. Aim of the Study. We therefore aimed at evaluating the anxiolytic and antidepressant potential of the plant in mice models. Methods. The dried stem bark was extracted with petroleum ether/ethyl acetate (50:50) mixture to obtain the extract, MAE. We employed Irwin’s test to identify the preliminary behavioral and autonomic effects. Subsequently, MAE was administered per os to male mice and subsequently assessed, 1 h later, for anxiety parameters in the elevated plus maze (EPM) and the regular Suok tests.The forced swim(FST) and tail suspension (TST) testswere employed to assess the antidepressant potential of the extract (100-1000mg kg−1). Results. In our preliminary assay,MAE(100-5000mg/kg) exhibited analgesic effects and a reduction in fear response in the Irwin’s test.The spontaneous locomotor activity was reduced at 1000mg/kg. Additionally, MAE (1000 mg/kg) increased the latency to PTZ-induced convulsions, and duration to sleep in the pentobarbitone induced sleeping time assay. MAE (1000 mg/kg), similar to diazepam, in the anxiolytic assay, increased the percentage time spent in the open arms while decreasing protected head dips and unprotected stretch attend postures in the EPM. Correspondingly, there was a reduction in anxiety-induced immobility and freezing in the Suok test (300 mg/kg) without loss of sensorimotor coordination. Additionally, there was a significant reduction in immobility duration in the FST (300 mg/kg) and TST (1000 mg/kg). Conclusion. The petroleum ether/ethyl acetate fractions of Maerua angolensis stem bark possess anxiolytic and acute antidepressant effects in mice.

Source: UCC
Anxiolytic-like effect of the leaves of Pseudospondias microcarpa (A. Rich.) Engl. in mice

ackground: Pseudospondias microcarpa is a plant used for managing various diseases including CNS disorders. Previous studies showed sedative and anticonvulsant effects, suggesting possible anxiolytic activity. This study therefore assessed the anxiolytic effects of P. microcarpa hydroethanolic leaf extract (PME) in mice. Methods: In the present study, anxiolytic-like effect of the extract in behavioural paradigms of anxiety – the elevated plus maze (EPM), light/dark box (LDB), social interac- tion test and stress-induced hyperthermia (SIH) – was evaluated. Results: Mice treated with PME (30–300 mg kg−1, p.o.) exhibited anxiolytic-like activity similar to diazepam in all the anxiety models used. The extract increased open arm activity (p < 0.05) in the EPM as well as increasing the time spent in the lit area in relation to the time spent in the dark area of the LDB. Sociability and preference for social novelty significantly (p < 0.05–0.001) increased in mice treated with PME. In the SIH paradigm in mice, both PME and the benzodiazepine receptor agonist, diazepam, significantly (p < 0.05) reduced the stress- induced increase in rectal temperature. The extract did not impair motor coordination and balance in the beam walk test. Conclusions: Results of the present study indicate that PME possesses anxiolytic-like effects in mice.

Source: UCC
APOBEC3G expression and HIV-1 infection in Burkina Faso

Abstract APOBEC3G is a potent inhibitor of HIV-1 replication, and act by deaminating cytidines in uracil on the negative strand of the viral cDNA. In this case-control study, APOBEC3G expression in subjects’ naïve to HAART infected by HIV-1 and the effect of APOBEC3G polymorphism on its expression were evaluated. The results show that the HIV-1 infected carriers of the G minor alleles of the variant rs8177832 had a higher expression of APOBEC3G mRNA than the controls carriers of the G minor allele. APOBEC3G polymorphisms could play an important role in the modulation of the HIV-1.

Source: UCC
APOBEC3G expression and HIV-1 infection in Burkina Faso

APOBEC3G is a potent inhibitor of HIV-1 replication, and act by deaminating cytidines in uracil on the negative strand of the viral cDNA. In this case-control study, APOBEC3G expression in subjects’ naïve to HAART infected by HIV-1 and the effect of APOBEC3G polymorphism on its expression were evaluated. The results show that the HIV-1 infected carriers of the G minor alleles of the variant rs8177832 had a higher expression of APOBEC3G mRNA than the controls carriers of the G minor allele. APOBEC3G polymorphisms could play an important role in the modulation of the HIV-1 dissemination

Source: UCC
APOBEC3G is a potent inhibitor of HIV-1 replication, and act by deaminating cytidines in uracil on the negative strand of the viral cDNA. In this case-control study, APOBEC3G expression in subjects’ naïve to HAART infected by HIV-1 and the effect of APOBEC3G polymorphism on its expression were evaluated. The results show that the HIV-1 infected carriers of the G minor alleles of the variant rs8177832 had a higher expression of APOBEC3G mRNA than the controls carriers of the G minor allele. APOBEC3G polymorphisms could play an important role in the modulation of the HIV-1 dissemination

Studies on host factors, particularly the APOBEC3G gene, have previously found an association with AIDS progression in some populations and against some HIV-1 strains but not others. Our study had two main objectives: firstly, to screen a population from Burkina Faso for three variants of APOBEC3G previously described, and secondly to analyze the effect of these three variants and their haplotypes on HIV-1 infection with Circulating Recombinant Forms (CRFs) present in Burkina Faso. This case control study involved 708 seropositive and seronegative individuals. Genotyping was done by the TaqMan allelic discrimination method. Minor allele frequencies of rs6001417 (p<0.05), rs8177832 (P<0.05), and rs35228531 (P<0.001) were higher in seronegative subjects. The rs6001417 and rs8177832 SNPs were associated with HIV-1 infection in an additive model (P<0.01). Furthermore, the SNP rs35228531 was also associated with HIV-1 infection in a dominant model (P<0.001). Odds ratio analysis of genotypes and alleles of the different APOBEC3G variants showed that there is a strong association between the minor genetic variants, genotype of the three SNPs, and HIV-1 status. Haplotype analysis demonstrated that rs6001417, rs8177832, and rs35228531 are in linkage disequilibrium. The haplotype GGT from the rs6001417, rs8177832 and rs35228531 respectively has a protective effect OR = 0.54 [0.43–0.68] with P<0.001. There was also associations between the haplotypes GGC OR = 1.6 [1.1;-2.3] P<0.05, and CGC OR = 5.21 [2.4–11.3] P<0.001, which increase the risk of infection by HIV-1 from almost two (2) to five (5) fold. This study demonstrates an association of rs6001417, rs8177832, and rs35228531 of APOBEC3G with HIV-1 infection in a population from Burkina Faso.

Source: UCC
APOBEC3G Variants and Protection against HIV-1 Infection in Burkina Faso

Studies on host factors, particularly the APOBEC3G gene, have previously found an association with AIDS progression in some populations and against some HIV-1 strains but not others. Our study had two main objectives: firstly, to screen a population from Burkina Faso for three variants of APOBEC3G previously described, and secondly to analyze the effect of these three variants and their haplotypes on HIV-1 infection with Circulating Recombinant Forms (CRFs) present in Burkina Faso. This case control study involved 708 seropositive and seronegative individuals. Genotyping was done by the TaqMan allelic discrimination method. Minor allele frequencies of rs6001417 (p<0.05), rs8177832 (P<0.05), and rs35228531 (P<0.001) were higher in seronegative subjects. The rs6001417 and rs8177832 SNPs were associated with HIV-1 infection in an additive model (P<0.01). Furthermore the SNP rs35228531 was also associated with HIV-1 infection in a dominant model (P<0.001). Odds ratio analysis of genotypes and alleles of the different APOBEC3G variants showed that there is a strong association between the minor genetic variants, genotype of the three SNPs, and HIV-1 status. Haplotype analysis demonstrated that rs6001417, rs8177832, and rs35228531 are in linkage disequilibrium. The haplotype GGT from the rs6001417, rs8177832 and rs35228531 respectively has a protective effect OR = 0.54 [0.43–0.68] with P<0.001. There was also associations between the haplotypes GGC OR = 1.6 [1.1;-2.3] P<0.05, and CGC OR = 5.21 [2.4–11.3] P<0.001, which increase the risk of infection by HIV-1 from almost two (2) to five (5) fold. This study demonstrates an association of rs6001417, rs8177832, and rs35228531 of APOBEC3G with HIV-1 infection in a population from Burkina Faso.

Source: UCC
Apologia, image repair and rhetoric in the defence of electoral defeat

Using the concepts of apologia, image repair and rhetoric, this paper examines the strategies employed by a former president of the Republic of Ghana to simultaneously maintain his reputation after losing the 2016 Ghanaian general elections and campaign for re-lection as the standard bearer of his party. The paper finds that the former president did not accept responsibility for the electoral loss, but used several indirect ways to deny responsibility for the defeat. He employed bolstering, accusation/attack, playing the victim, throwing a challenge and the God’s will factor as defence strategies in order to repair his image. He exploited the Aristotelian appeals of logos, ethos and pathos to boost his persuasion. In doing so, he deployed several rhetorical tools such as metaphor, allusion, rhetorical questions and parallelism to enhance the expression of the defence strategies. The analysis reveals that, as noted in the literature, some of the image repair strategies espoused by Benoit (1995, 2015), for example, outright denial and mortification, hardly apply to political contexts – the former President’s defence was indirectly expressed. Thus, the paper concludes that combining the concepts of apologia, image repair and rhetoric in the analysis of political discourse can illuminate political discourse analysis. The paper has implications for communicating defence, reputation repair and political rhetoric

Source: UCC
Appearance of negative differential conductivity in graphene nanoribbons at high-harmonicsa)

We theoretically study current dynamics of graphene nanoribbons subject to bias dc and ac driven fields. We showed that graphene nanoribbons exhibit negative high-harmonic differential conductivity. Negative differential conductivity appears when bias electric filed is in the neighborhood of applied ac filed amplitude. We also observe both even and odd high-harmonic negative differential conductivity at wave mixing of two commensurate frequencies. The even harmonics are more pronounced than the odd harmonics. A possible use of the present method for generating terahertz frequencies at even harmonics in graphene is suggested

Source: UCC
Application of a rational model in Gis for flood risk assessment in Accra, Ghana

Accra has been experiencing periodic flooding that affect properties and lives. The government seeing the dangers involved has commissioned institutions such as Ministry of Works and Housing, Town and Country Planning and City Engineers to identify flood risk zones and adapt measures that will help reduce flood damages. These institutions identify flood risk zones using conventional methods such as watermarks on buildings and reported cases in the news media. Works carried out by these agencies were not able to give details about potential areas that are likely to experience this extreme event. Hence there was the need to find a new method of identifying and mapping of potential flood risk zones. To determine flood risk zones in Accra and its environs a hydrological model (modified rational model) was integrated into the GIS platform, by the arithmetic overlay operation method, using operators such as addition and division. The results show that although the delineated areas experienced a same rainfall intensity of 140.2 mm the flood intensities of these areas could differ. The high flood risk zone covers 35.66 percent of the study area, whiles the low risk zone covers 26.85 percent. The areas that will potentially experience periodic floods with a given input of rainfall are mostly below the 350-meter contour

Source: UCC