Browsing by Author "Ofori, M."
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Item Antiplasmodial constituents from the stem bark of Polyalthia longifolia var pendula(Phytochemistry Letters, 2014-11) Annan, K.; Ekuadzi, E.; Asare, C.; Sarpong, K.; Pistorius, D.; Oberer, L.; Gyan, B.A.; Ofori, M.Along with two known compounds (1 and 2), four new clerodane diterpenes were isolated and identified from the stem bark of Polyalthia longifolia: cleroda-3-ene pyrrole-15,16-dione (3), cleroda-3-ene, pyrrolidine-15,16-dione (4), cleroda-3,13(14)E-diene-15,16-diamide (5), and cleroda-3-ene-15,16-diamide (6). Their structures were elucidated by combinations of NMR, MS and IR. Using the WHO Mark III Microtest assay, the isolated compounds were evaluated for their antiplasmodial effects. They showed antiplasmodial effects, with IC50s ranging from 4.5 to 213.8 μM. © 2014 Phytochemical Society of Europe. Published by Elsevier B.V. All rights reserved.Item Elevated levels of nitric oxide and low levels of haptoglobin are associated with severe malarial anaemia in African children(Acta Tropica, 2002-08) Gyan, B.; Kurtzhals, J.A.L.; Akanmori, B.D.; Ofori, M.; Goka, B.Q.; Hviid, L.; Behr, C.Severe malarial anaemia (SA) is a major complication of malaria and an important cause of child mortality and morbidity. However, the pathogenesis behind SA is poorly understood. Nitric oxide (NO) is known to play a protective role against clinical malaria but is also suggested to have a pathogenic role in cerebral malaria (CM). Erythrophagocytosis by splenic macrophages has been implicated in the pathogenesis of SA. In this study, plasma levels of NO, neopterin, haptoglobin and C-reactive protein (CRP) were measured in paediatric patients with CM, n=77, SA (n=28) and uncomplicated malaria (UM n=53). Haptoglobin levels were significantly lower in SA (median (interquartile range) 25 (17-59) mg/l) than in both CM and UM (40 (24-80) mg/l and 110 (60-160) mg/l, respectively, P<0.001). In contrast, NO levels were higher in SA (38 (28-51) μmol/l) than in CM and UM (21 (15-32) μmol/l and 10.3 (5.6-17) μmol/l, respectively, P<0.001). A significant negative correlation between haptoglobin and NO was seen in the SA group. No such correlation was observed within the UM or CM groups. No significant differences in neopterin levels were observed between any of the three groups, neither was there any correlation between parasitaemias and neopterin levels. The low haptoglobin and high levels of NO in this SA group may contribute to haemolysis. Taken together our results support the hypothesis that immune-mediated erythrocyte destruction is involved in the pathogenesis of malarial anaemia. © 2002 Elsevier Science B.V. All rights reserved.Item Experiences of Spouses of Men with Advanced Prostate Cancer in the Accra Metropolis(University Of Ghana, 2017-07) Ofori, M.Spouses play significant roles in the care of their husbands. This comes with a lot of experiences in times of ill-health of the men and may have several effects on the spousal caregiver. It is likely to affect the woman’s physical, social, psychological and spiritual wellbeing. This study therefore explored the experiences of spouses of men with advanced prostate cancer in the Accra Metropolis using the Quality of Life Model Applied to Family Caregivers (Ferrell, 2001) as an organising framework to understand their experiences. An exploratory descriptive qualitative research design with purposive and snowball sampling techniques were used to recruit women above 18 years living with and having any intimate relationship with men with advanced prostate cancer within the Accra Metropolis. Data saturation was achieved with sample size of 13 participants. The recruitment outlet was the Korle-Bu Teaching Hospital. A semi-structured interview guide was used for data collection from only participants who signed an informed consent form. The interviews were recorded with participants’ permission, and transcribed. Anonymity and confidentiality were ensured during the study. Braun and Clarke’s technique of thematic content analysis was adopted for data analysis. Five major themes were derived and described as follows: Physical, social, psychological, spiritual wellbeing and spousal involvement. It was found that spouses of men with advanced prostate cancer experienced fatigue, sleep disruptions, pain, loss of appetite and effects of pre-existing diseases. The spouses experienced isolation, financial burden, had no time for leisure activities. Again, the spouses experienced anxiety, depression, and fear but had hope for their husbands’ recovery. It was also revealed that the participants lacked adequate knowledge in prostate cancer and were not involved in the treatment of their husbands. It was recommended that spouses should be included in the choice of treatment and care for men with advanced prostate cancer, and there should be support groups for spouses of men with advanced prostate cancer.Item Generation of HIV-1 primary isolates representative of plasma variants using the U87.CD4 cell line(Journal of Virological Methods, 2010) Heeregrave, E.J.; Ampofo, W.K.; Tetteh, J.K.A.; Ofori, M.; Ofori, S.B.; Shah, A.S.; Pollakis, G.; Paxton, W.A.In order to obtain HIV-1 primary isolates in settings with limited access to donor PBMCs, a culture method was developed where patient PBMCs infected with HIV-1 were cultured together with U87.CD4 cells. Using this non-laborious method, it is possible to harvest virus solely on the basis of syncytia formation and circumventing monitoring of viral replication by CA-p24 ELISA. Primary isolates from 23 out of 33 patients (70%) were isolated successfully. From PCR amplification and sequencing of the V1V5 region of the viral gp120 envelope gene, primary isolates were compared with variants obtained from plasma and PBMCs of 13 patients. The primary isolates of seven patients (54%) resembled closely the plasma viral quasispecies, whereas different variants were isolated from the other patients (46%). Three patients harboured a dual infection, while this remained unnoticed from sequencing the plasma or PBMC compartment. The primary isolates were highly infectious for TZM-bl cells and could infect CD4-enriched lymphocytes. This study demonstrates that it is possible to grow viral isolates using a non-laborious and simple method. These isolates may be used in the field for studies on antiretroviral therapy or for vaccine trials.Item Human leukocyte antigen class I polymorphisms influence the mild clinical manifestation of Plasmodium falciparum infection in Ghanaian children(Human Immunology, 2011-10) Yamazaki, A.; Yasunami, M.; Ofori, M.; Horie, H.; Kikuchi, M.; Helegbe, G.; Takaki, A.; Ishii, K.; Omar, A.H.; Akanmori, B.D.; Hirayama, K.A prospective study that included 429 children for active detection of mild malaria was conducted in a coastal region of Ghana to reveal whether the incidence of malaria is affected by human leukocyte antigen (HLA) polymorphism. During 12 months of follow-up, 85 episodes of mild clinical malaria in 74 individuals were observed, and 34 episodes among them were accompanied with significant parasitemia at >5000 infected red blood cells per cubic millimeter. Attributable and relative risks conferred by genetic factors in the HLA region were evaluated by comparison of the incidence in children, stratified by carrier status, of a given allele of HLA-A, -B, -DRB1 and TNFA promoter polymorphism. HLA-B*35:01 reduced the incidence by 0.178 events per person per year (0.060 versus 0.239 for B*35:01-positive and -negative subpopulations, respectively), and a relative risk of 0.25, which remained statistically significant after Bonferroni's correction for multiple testing (p c = 8.2 × 10 -5). Further, HLA-B*35:01 and -B*53:01 exhibited opposite effects on the incidence of malaria with significant parasitemia. When parasite densities in different HLA carriers status were compared, HLA-A*01 conferred an increase in parasite load (p = 6.0 × 10 -7). In addition, we found a novel DRB1 allele that appears to have emerged from DRB1*03:02 by single nucleotide substitution. © 2011 American Society for Histocompatibility and Immunogenetics.Item In Vitro Activity of Extract and Fractions of Natural Cocoa Powder on Plasmodium falciparum(2012) Amponsah, S.K.; Bugyei, K.A.; Osei-Safo, D.; Addai, F.K.; Asare, G.; Tsegah, E.A.; Baah, J.; Ofori, M.; Gyan, B.A.Several flavonoids isolated from certain plants have demonstrated antiplasmodial activity, after their initial indigenous use in malaria treatment. Cocoa has been found to be a rich food source of flavonoids in comparison with many common foods and beverages. The aim of this work was to investigate the in vitro activity of natural cocoa powder on the growth of Plasmodium falciparum. Prepared crude methanol extract was partitioned successively with petroleum ether, ethyl acetate, chloroform, and butanol. Total flavonoid concentration in the crude methanol extract and fractions was measured by the AlCl3 colorimetric assay. Direct inhibitory activity of the natural cocoa powder was assessed by culturing extract and fractions with P. falciparum in vitro. Greater antiplasmodial activity was observed in nonpolar solvent fractions (chloroform, ethyl acetate, and petroleum ether) compared with polar solvents. The chloroform fraction was most active, with mean – SEM 50% and 90% inhibition concentrations of 48.3 – 0.9 and 417 – 7.8 lg/mL, respectively. The study showed a weak association between total flavonoid concentration and antiplasmodial activity. Early trophozoite (ring-stage) synchronized cultures treated with the chloroform fraction of natural cocoa powder showed a decline in growth. Further reduction in parasitemia was also observed for other erythrocytic stages. These results suggest that natural cocoa powder has measurable direct in vitro inhibitory effect on P. falciparum and support the anecdotal reports of its ability to prevent malaria as a result of regular intake as a beverage.Item In vitro anti-plasmodial activity of three herbal remedies for malaria in Ghana: Adenia cissampeloides (Planch.) Harms., Termina liaivorensis A. Chev, and Elaeis guineensis Jacq(Pharmacognosy Research, 2012-10) Annan, K.; Sarpong, K.; Asare, C.; Dickson, R.; Amponsah, KI.; Gyan, B.; Ofori, M.; Gbedema, S.Y.Background: Herbal remedies of Adenia cissampeloides, Terminalia ivorensis, and Elaeis guineensis among others have been used in Ghana for the treatment of various ailments including malaria. However, most of these remedies have not been scientifically investigated. Objective: This study, therefore, seeks to investigate the anti-plasmodial activity of these plants. Materials and Methods: The ethanolic extracts of A. cissampeloides stem, T. ivorensis stem bark, and E. guineensis leaves were tested for in vitro anti-plasmodial activity against chloroquine-resistant strains of Plasmodium falciparum. Thin blood films were used to assess the level of parasitemia and growth inhibition of the extracts. Results: The IC50 of A. cissampeloides, T. ivorensis, and E. guineensis were 8.521, 6.949, and 1.195 g/ml, respectively, compared to artesunate with IC50 of 0.031 g/ml. Conclusion: The result of this study appears to confirm the folkloric anti-malarial use these plants.Item Pharmacokinetics and in vivo chemosuppressive activity studies on cryptolepine hydrochloride and cryptolepine hydrochloride-loaded gelatine nanoformulation designed for parenteral administration for the treatment of malaria(Acta Tropica, 2013-09) Kuntworbe, N.; Ofori, M.; Addo, P.; Tingle, M.; Al-Kassas, R.The main objective of this investigation was to establish the pharmacokinetics profile and in vivo chemosuppressive activities of cryptolepine hydrochloride-loaded gelatine nanoparticles (CHN) designed for parenteral administration for the treatment of malaria in comparison to the drug free in solution (CHS). Single-dose pharmacokinetics was investigated in Wistar rats by administering CHN or CHS (equivalent to 10. mg/kg of drug) by IV bolus injection via the lateral tail vein. The drug concentration in plasma was monitored over a 24-h period following administration. Chemosuppressive activity was investigated in Wistar rats challenged with P berghei parasites. Animals were given a daily dose of either CHN or CHS, equivalent to 2.5-100. mg/kg by intraperitoneal injection. The level of parasitaemia was determined by light microscopy by examining Giemsa-stained thin blood smears prepared from the tail end on day four of infection. It was found that CHN attained a higher (4.5-folds) area under the curve (AUC (0-24)) compared to CHS. CHS however produced a higher volume of distribution (4-folds). Distribution and elimination rates were higher with CHS which resulted in a lower (11.7. h) elimination half-life compared to that of CHN (21.85. h). The superior pharmacokinetic profile of CHN translated into superior chemosuppressive activity at all dose levels relative to CHS. As a conclusion, loading cryptolepine hydrochloride into gelatine nanoparticles improved both pharmacokinetics and in vivo antiplasmodial activity of the compound with the highest chemosuppression (97.89. ±. 3.10) produced by 100. mg/kg of CHN. © 2013 Elsevier B.V.Item Prevalence of Human Immunodeficiency Virus, Syphilis, Hepatitis B, and Risk Factors Among Truck Drivers in Tema, Ghana(University of Ghana, 2014-07) Boahemaa- Atta, P.; Ofori, M.; Asare-Anane, H.; University of Ghana, College of Health Sciences , School of Biomedical and Allied Health Sciences , Department of PathologyHuman immunodeficiency virus (HIV), Hepatitis B virus (HBV) and syphilis infections have now spread to all parts of the world, and the rate of infection is found to be high in the cities with high number of mobile populations. One of such mobile populations is long distance truck drivers. Although studies from Asia, Europe, USA, and elsewhere have documented high prevalence of HBV, HIV and syphilis infections among truck drivers (long and short distance), such data are sparse from Africa. To my knowledge there is no such data from Ghana. This study investigates the prevalence of HIV, HBV, syphilis and the risk factors among truck drivers using the seaport at Tema. The study is a cross sectional study carried out between the months of March, 2013 and June, 2013 among truck drivers at Tema seaport. All the 106 consenting participants completed a structured questionnaire assessing socio-demographic characteristics and risk factor profile for the infections under investigation. Blood samples from consenting participants were tested at the Public Health Reference Laboratory, Korle-Bu Teaching Hospital, Accra, Ghana for the presence of antibodies to HIV-1 and 2, using Genscreen™ ULTRA HIV Ag-Ab (Bio-Rad Laboratories, Hercules, CA). Antibodies to syphilis was tested using [T. pallidum haemagglutination assay (TPHA) test; Serodia Fujirebio]. Hepatitis B surface antigen (HBsAg) was tested using Roche COBAS e411 analyzer with elecsys HBsAg II quant test (Roche Diagnostics, Germany). A total of 1250 truck drivers (Ghanaian and non-Ghanaian residents) at the Tema port were eligible for the study, however 106 (8.4%) of the eligible took part in the study. None of the foreign citizens (non-Ghanaian residents) took part in the study. The mean age of the participants was 40.56 ± 11.56 years (range: 18–74 years). For the 106 participants tested, HIV sero- prevalence was 0.98% (1 out of 106), 14.2% (15 out of 106) tested seropositive for HBsAg and reactive syphilis serology was noted in 3.8% (4 out of 106) of the participants. On multivariant analysis, the independent determinants for HBV infection were being a long distance driver [Odds Ratio (OR): 6.88; 95% CI 0.86-52.89], having multiple sexual partners (OR: 6.36; 95% CI 1.35 - 29.79) and previous visit to commercial sex worker (OR: 6.85; 95% CI: 0.89-52.89). Interestingly, knowledge of HIV, HBV and syphilis infections and preventive measures were high among the truck drivers.The data indicates a low HIV prevalence among truck drivers in Ghana, however the high prevalence of HBV and syphilis coupled with their risky behaviour suggest an increase potential risk of HIV in the truck driving population in Ghana.Item Soluble Human Leukocyte Antigen-G Expression In Pregnancy Success and Early Pregnancy Loss in Korle-Bu Teaching Hospital(University of Ghana, 2014-07) Blebu, S. I.; Adjei, A. A.; Ofori, M.Background: Human Leukocyte Antigen (HLA) -G is a non-classical major histocompatibility complex (MHC) class I protein which has been described as being selectively expressed on the invasive trophoblast at the materno-foetal interface at the beginning of pregnancy. HLA-G has the potential role of protecting the trophoblast from cytotoxicity and enhancing maternal acceptance of the semi-allogeneic foetus by modulating the maternal immune system. HLA-G exerts several immunomodulatory effects, being beneficially implicated in embryo implantation and foetal survival. HLA-G inhibits the activation of the immune cells, and primes them into cytokine secretion profiles to control trophoblast invasion and maintain a local immunosuppressive environment for successful implantation and pregnancy survival. HLA-G has the ability to modulate the release of cytokines from human allogeneic peripheral blood mononuclear cells, and generate allogeneic cytotoxic T lymphocytes (CTLs) response in a concentration-dependent manner. Soluble isoforms of HLA-G has also been demonstrated to inhibit trophoblast invasion of the maternal decidua. Setting/Location: The study was conducted at the Department of Obstetrics and Gynaecology in the Korle-Bu Teaching Hospital. Korle-Bu Teaching Hospital is a leading teaching hospital and a major referral centre in Ghana. Aim: The aim of the study was to determine the role of soluble HLA-G in pregnancy success and early pregnancy loss in Korle-Bu Teaching Hospital. Methods: This study involved eighty participants made up of twenty eight (28) normal pregnant women who had normal delivery, thirty two (32) women who had spontaneous or recurrent abortion, ten non-pregnant women and ten healthy men. A semi-structured questionnaire was administered to each consented participant to document their sociodemographic characteristics, and the history of pregnancy was obtained from the clinic folders. 5ml of venous blood samples were collected from each consented participant and the plasma used to determine sHLA-G levels by Enzyme-linked immunosorbent assay (ELISA). Results: The median sHLA-G levels were higher among women who had spontaneous abortions (66.5 U/ml) as compared to pregnant women who had normal delivery (49.53 U/ml), this was statistically significant. The first and second trimester sHLA-G levels of women who had spontaneous abortion are 66.53U/ml and 74.08U/ml respectively and was not statistically significant. The first and second trimester sHLA-G levels of pregnant women who had normal delivery are 39.73U/ml and 69.06U/ml respectively and were also not statistically significant. Healthy males had sHLA-G level (79.11 U/ml) as compared to healthy non-pregnant women (58.28 U/ml) but the difference was not statistically significant. Maternal sHLA-G levels was not statistically significant (P=0.26) in relation to maternal age and birth weight (P=0.38). Conclusion: The results indicate that high levels of sHLA-G may adversely affect pregnancy outcome whilst reduced sHLA-G expressions may enhance pregnancy survival. There was not a significance difference between gestation and sHLA-G levels of women who had spontaneous abortion and normal pregnancy in pregnant women who had normal delivery. The sHLA-G levels were not affected by gender; healthy males had higher sHLA-G level as compared to healthy non-pregnant women, who were all in normal conditions of health but the difference was not statistically significant. This suggests that high sHLA-G levels in healthy individual may play a role in immunosurveilance. The history of contraceptive use had no effect on sHLA-G levels of women who had spontaneous abortion. Finally, there was no relationship between maternal age and corresponding sHLA-G levels, which had no effect on infant birth weight.