ghanaopendata/ghanaian-research-english huggingface dataset:
Pesticide residues and potential health risk through the consumption of fish from Ibadan, Oyo state, Nigeria

This study was conducted to determine the concentration of organochlorine, organophosphorus and pyrethroid pesticide residues present in some selected fish species (Oreochromis niloticus, Clarias gariepinus, Trachurus trachurus, Sardinella madenrensis and Scomber japonicus) from markets in Ibadan, Oyo state, Nigeria. Further studies were carried out to determine the health risk posed on the human population from the consumption of the selected fish species. The extraction procedure and clean-up was done using Hexane/Acetone solvent system. The five fish species were analyzed for pesticide residues by gas chromatography equipped with electron capture detector. Nine (9) organophosphorus pesticides (Methamidopho, Phorate, Fonofos, Primiphos-methyl, Chlorpyrifos, Malathion, Fenithrothion, Parathion-ethyl and Profenofos), nine (9) pyrethroid pesticides (Allenthrin, Bifenthrin, Fenpropathrin, Lambda-cyhalothrin, Cyfluthrin, Cypermethrin, Fenvalerate, Delta-methrin and Permethrin) and thirteen (13) organochlorine pesticides (β-HCH, δ-HCH, Heptachlor, γ-Chlordane, α-endosulfan, β-endosulfan, p,p’-DDE, Dieldrin, Endrin, p,p’-DDD, p,p’-DDT, Methoxychlor and Aldrin) were detected. The mean concentrations detected for organophosphorus pesticides ranged from 0.0024±0.0002 µg/g to 0.0076±0.0031 µg/g, pyrethroids ranged from 0.2154±0.0066 µg/g to 7.6504±0.0259 µg/g and organochlorine pesticides ranged from 0.1048±0.0079 µg/g to 3.2062±0.0348 µg/g. The health risk assessment analysis performed on the samples had health index of less than 1 (HI<1) for pyrethroids and organophosphorus pesticides in all fish species analyzed, indicating that their intake through fish consumption may pose no danger or harm to its consumers. On the other hand, health index was less than 1 (HI<1) for most organochlorines, with the exception of heptachlor, dieldrin and aldrin which had HI greater than 1 (HI>1) in some fish species, indicating that there may be harm in continuous consumption of such fish which could result in detrimental chronic effects on the consumer.

Source: KNUST
Pesticide residues in water, sediment and fish from Tono Reservoir and their health risk implications

Levels of organochlorine (OC) and organophosphorus (OP) pesticide residues in fish, sediments and water and their health risk associated with the consumption of the fish from the Tono Reservoir, Ghana were evaluated. The analytical methods included solvent extraction of the pesticide residues using ultrasound sonication and soxhlet extraction and their subsequent quantification using GC equipped with electron capture detector and pulse flame photometric detector after clean-up on activated silica gel/anhydrous sodium sulphate. A total of 29 pesticides comprising 16 OCs and 13 OPs were analyzed, out of which aldrin, p,p′-DDE and p,p′-DDD were detected in fish and sediment samples. The results showed that all the residues in water had their concentrations below the detection limit. Mean concentrations of organochlorine pesticide (OCP) residues in fish ranged from 0.017 to 0.17, 0.043 to 0.30, 0.027 to 0.243 and 0.097 to 0.263 μg/g in Sarotherodon galilaeus, Clarias anguillaris, Schilbe intermedius and Marcusenius senegalensis respectively. Mean concentrations of organophosphates pesticides ranged from 0.080 to 0.090, 0.080 to 0.087 and 0.050 to 0.063 μg/g in C. anguillaris, S. intermedius and M. senegalensis respectively. The level of chlorpyrifos in S. galilaeus was 0.160 μg/g. Mean concentrations of OCP residue in sediments ranged from 0.047 to 0.090 μg/g. Aldrin recorded the highest level while p,p′-DDD recorded the lowest level. The mean concentrations for all the detected residues were below the WHO/FAO maximum residue limits. Health risk estimation revealed that aldrin in M. senegalensis had great potential for systemic toxicity to consumers.

Source: KNUST
Pesticides handling and use in four selected agro – ecological zones in Ghana

This study which focused on farmers’ handling and use of pesticides was conducted in four selected agro – ecological zones in Ghana. The study aimed at determining the types of crops on which pesticides are applied, the type of pesticides of used by farmers, the level of protection of farmers and farmers’ perceptions about pesticides handling and use within the four selected agro – ecological zones. Data were gathered from two randomly selected farming communities of each zone selected; namely Techiman and Agogo (Transition zone), Mankranso and Akomadan (Forest zone), Tamale and Navorongo (Savannah zone) and Amasaman and Abokobi (Coastal-Savannah zone). Data were obtained through the administration of questionnaire in August, 2011. A total of 400 farmers were randomly interviewed. The results showed that about 70 % of the farmers have had formal education up to the Basic level with only 1 % having Tertiary education. Male farmers (92 %) mostly handled and applied pesticides. The study also revealed that insecticides and herbicides are by far the most frequently used pesticides across the ecological zones. Vegetables and cash crops like cocoa and citrus are the crops mostly treated with pesticides. The protective devices used by the farmers were not standard due to poverty. About 81 % know about expiry date of pesticides but 49 % really check expiry date on pesticides. Although 62.3 % are not aware of Specific Restricted Entry Interval, only about 3.7 % usually enter sprayed field few hours after application. The study also revealed that more than half (58 %) of the farmers have had no agricultural extension education on the handling and use of pesticides. About 26 % of the farmers use empty pesticides containers to keep drinks and food items for future use, which poses serious health threat to the farmers. There is therefore the need to intensify agricultural extension services and various awareness programmes on pesticides handling and use in Ghana.

Source: KNUST
Pharmaceutical and Biological Evaluation of Brands of Albendazole Tablets on the Ghanaian Market.

The dissolution characteristics of the various brands of albendazole have long been a problem to manufacturers. Since dissolution affects the bioavailability of drugs, it is important that all steps be taken to solve this problem once and for all. The possible reasons for the problematic dissolution profile of albendazole are differences in manufacturing processes, compression pressures, levels of excipients particularly, binders, diluents, crystal size and structure of albendazole granules used for compression etc. The effect of chewing on the dissolution was also investigated. The effect of the sparing solubilities and erratic dissolution profiles of albendazole was investigated by their activity on the mobility of earth worms (Lumbricus terretis). A simple analytical method was developed for the assay of albendazole using high performance liquid chromatography (HPLC). A solvent system of 200 volumes of water, 800 volumes of methanol with 3ml of sulphuric acid in methanol was used. The chromatographic system was equipped with a 254nm detector and C18 column. The method developed was found to be specific, precise, accurate and linear. The method was also robust, flow rates of 0.5ml/min and 1.0ml/min were recommended. The limit of detection (LOD) and limit of quantification (LOQ) were respectively 24ug/ml and 80ug/ml. The following brands of albendazole were used: zentel, tanzol, alben, wormplex, wormzap, albendaven, expel, nesben, and benzil. Upon investigation, chewing a tablet of albendazole improves drastically its dissolution and efficacy. It is therefore advised that all albendazole tablets be chewed before swallowing. All the brands of albendazole effectively killed the worms after three hours of experimentation. The differences in paralysis time were investigated by chemical assay. The purpose of the chemical assay (via non-aqueous titration and HPLC) was based on the premise that differences in the active ingredient content could contribute to the difference in the paralysis time. Using non-aqueous titration, only sample K was found to contain the appropriate amount of albendazole by virtue of its % active ingredient content. However, using HPLC samples K, B, C, D and A contained the appropriate amount of active ingredient using the British Pharmacopoeia (BP), United States Pharmacopoeia (USP) and the International Pharmacopoeia (IP) as references. The two methods employed revealed the sensitivity, accuracy and reliability of HPLC over non-aqueous titration, in the analysis of albendazole. The differences in the % active ingredient content contributed to the effects of tablets on the paralysis of the worms, hence playing a crucial role. This was demonstrated by the paralysis activities of samples A, B and C over the other brands.

Source: KNUST
Pharmaceutical supply chain network in Ghana

Pharmaceutical supply chain network basically means the route through which pharmaceuticals are distributed from manufacture, until it gets to the final consumers. The competitive nature of the pharmaceutical industry suggests that those who are able to apply supply chain principles to their business activities are likely to beat their competitors. The nature of pharmaceuticals makes it important for special attention to be given to it. It is in this light that government has entrusted the production and distribution of these products into the hands of specially trained people. However there is evidence of increasing level of counterfeit pharmaceutical in Ghana and other parts of the world. This study seeks to analyze the path or route through which pharmaceuticals are distributed from manufacture, until it gets the final consumer and make recommendations to the distributors, government and regulatory authorities. Questionnaire and interviews were used as the main method of data collection. Other documents obtained from the Pharmacy council were also used as source of data. The total population for the study was all the pharmaceutical distribution outlets in Ghana. A sample size of 40 outlets was chosen for the study. The main findings arrived at indicated that manufactures of pharmaceuticals supply to wholesale pharmacies, who intend supply to medical stores, retail pharmacies, licensed chemical sellers and health institutions, who also supplies to the consumers. Sales promotion was found to have been integrated in some cases. Informal importation was also found to exist in Ghana.

Source: KNUST
Pharmacogenetic associations with plasma efavirenz concentrations and clinical correlates in a retrospective cohort of Ghanaian HIV-infected patients

Objectives: Efavirenz is widely used in first-line antiretroviral therapy in sub-Saharan Africa. However, exposure to efavirenz shows marked interindividual variability that is genetically mediated with potential for important pharmacodynamic consequences. The aims of this study were to assess the frequencies of CYP2B6, CYP2A6, UGT2B7 and CAR single nucleotide polymorphisms (SNPs) and their impact on plasma efavirenz concentration and clinical/ immunological responses in Ghanaian patients. Methods: Genomic DNA from 800 HIV-infected patients was genotyped for selected SNPs by real-time PCR-based allelic discrimination. Mid-dose plasma efavirenz concentrations were measured for 521 patients using HPLC with UVdetection. Clinical outcomes in 299 patients on efavirenzwere retrospectively assessed.Univariate andmultivariatelinear regressionwereperformedusingbest subset selection.Time-to-eventoutcomeswereanalysedusingaCox proportional hazards regressionmodel. Results: The variant allele frequencies for CYP2B6 516G.T (rs3745274), CYP2B6 983T.C (rs28399499), CYP2A6 248T.G (CYP2B6*9B; rs28399433), UGT2B7 802C.T (UGT2B7*2; rs7439366), UGT2B7 735A.G (UGT2B7*1c; rs28365062) and CAR 540C.T (rs2307424) were 48%, 4%, 3%, 23%, 15% and 7%, respectively. CYP2B6 516G.T, CYP2B6 983T.C and CYP2A6 248T.G were associated with significantly elevated efavirenz concentrations. A trend towards association between plasma efavirenz concentration and CAR 540C.T was observed. CYP2B6 516G homozygosity was associated with immunological failure [adjusted hazards ratio compared with T homozygosity, 1.70 (1.04–2.76); P¼0.03]. Conclusions:CYP2B6andCYP2A6SNPswereassociatedwithhigher plasmaefavirenzconcentrationsduetoreduction inmajor and minor phase I routes of elimination, respectively. Further prospective studies are needed to validate the pharmacodynamic correlates of these polymorphisms in this population.

Source: KNUST
Pharmaceutical equivalence studies on some locally manufactured brands of paracetamol sold in Kumasi.

Paracetamol (acetaminophen), N-(4-Hydroxyphenil)-acetamide an over-the-counter analgesic, antipyretic and anti-inflammatory drug is a widely used drug. There are numerous generics of Paracetamol tablets available within the health delivery system in Ghana and globally. This study sought to determine the pharmaceutical equivalences between some selected brands of Paracetamol produced locally and compared to one imported brand from England. Thirteen brands of Paracetamol tablets plus one imported brand (M&A Pharmachem, England) were purchased from licensed pharmacies within Kumasi. Samples were all immediate-release conventional, oral dosage forms and were coded to avoid bias. Pharmacopoeial and non-pharmacopoeial tests such as friability, thickness, hardness, uniformity of diameter, uniformity of weight, disintegration time, in vitro dissolution testing and assay were used to assess the pharmaceutical equivalence of the various brands of Paracetamol tablets. The paddle method was used for the dissolution testing. UV spectroscopy was used for the assay analysis of all the brands of Paracetamol tablets sampled. All brands complied with the official specifications for identification, diameter, thickness and hardness. PLE, PMA, PPH, and POC passed all the test conducted on it. However brands PSA, PTA and PDA passed majority of the tests and failed the test for assay. Brands PAS, PMG, and PAN failed the dissolution rate test and assay. Brand PKI also failed the test for disintegration and dissolution. PAE failed the weight uniformity test but passed the other tests. PAR performed poorly by failing the test for friability, weight uniformity and assay. Statistically all brands are different from the standard in at least one test. Only Brands PLE, PPH and POC are pharmaceutically equivalent to the standard (PMA) and may be used as alternatives if they proved to be bioequivalent.

Source: KNUST
Pharmacognostic studies and anti -infective properties of hilleria latifolia (lam.) h. walt. (phytolaccaceae)

The study sought to investigate the Pharmacognostic properties and anti-infective activities of Hilleria latifolia (Lam.) H. Walt. which has immense medicinal use in the African sub-region, especially Ghana. The Pharmacognostic properties of the plant as well as the antimicrobial and antiplasmodial activities were assessed. Pharmacognostic studies carried out on the plant revealed the presence of abundant calcium oxalate crystals in all plant parts. Tetragonal crystals were found beneath the epidermal cells and were not embedded in the palisade cells. Different types of prismatic crystals and rosette crystals were found in the palisade cells of the leaf. The leaves had anomocytic stomatal arrangement and possessed abundant prismatic crystals (3.9-110.5 µm in length) and multicellular clothing trichomes (94.7-347.2 µm in length). Vein islet and veinlet termination numbers averaged 18 and 32 respectively. The physical parameters revealed the highest extractive value for alcohol in all plant parts; leaf (24.048 ± 0.208 % w / w ), stem (10.012 ± 1.652 % w / w ) and root (12.036 ± 0.564 % w / w ). The lea f gave the highest values for total ash (16.667 ± 0.286 % w / w) and water soluble ash (16.028 ± 0.434 % w / w ). Phytochemical screening revealed the presence of alkaloids, triterpenoids, tannins and glycosides in all parts of the plant. Flavonoids, phytosterols and saponins were present only in the roots and anthraquinones were absent in all parts of the plant. Pharmacopoeial standards for the plant have also been established through the pharmacognost ic studies. The methanolic, ethyl acetate and petroleum ether extracts of the leaves, stem and roots were tested against six micro-organisms; B. subtilis, E. coli, P. aeruginosa, S. aureus, S. pyogenes and C. albicans using the agar dilution method. The ethyl acetate extract of the leaves was the most active, inhibiting B. subtilis, E. coli, P. aeruginosa and C. albicans at MIC’s between 250 µg/ml and 500 µg/ml; the positive controls used were Ciprofloxacin vi and Ketoconazole for bacteria and fungus respectively. The methanol extract of the whole plant, tested against Mycobacterium smegmatis, recorded an MIC above 500 µg/ml with the positive control Rifampicin recording an MIC of 0.01 µg/ml. The antiplasmodial activities of the extracts were investigated in multidrug resistant P. falciparum (K1) parasites using the Parasite Lactate Dehydrogenase Assay. The petroleum ether extract of the leaf, gave the highest antiplasmodial activity with IC 50 value of 28.18 µg/ml. The petroleum and ethyl acetate root extracts showed moderate antiplasmodial activities with IC 50 values of 100 µg/ml each. Similarly, that of the stem was 89.25 µg/ml. The positive controls used, Artemether and Chloroquine, gave IC 50 values of 19.3 ng/ml and 412.01 ng/ml respectively. The present work has demonstrated that Hilleria latifolia possesses some level of anti-infective activity as suggested by folklore medicine, thus giving scientific credence to its use.

Source: KNUST
Pharmacological Management of Hypertensive Clients at Hypertension/Diabetes Clinic of KNUST Hospital

The main aim of the study is to identify, describe and assess the pharmacological management of hypertensive clients at the Hypertension and Diabetes (HPT/DM) Clinic of the Kwame Nkrumah University of Science and Technology (KNUST) Hospital, Kumasi. HPT is a major public health issue because of its high prevalence and serious complications. Appropriate and timely management using pharmacological and non-pharmacological therapy is essential to minimize complications and death resulting from HPT. A cross sectional retrospective study involving 100 clients was employed in this study. Data was collected through the administration of semi structured questionnaires from 1st July to 31st October, 2011. Case notes of the clients were also reviewed to obtain additional information and also to confirm and validate the clients’ responses. The classes of Antihypertensive Agents (AHA) commonly used at the HPT/DM Clinic of the KNUST Hospital are calcium channel blockers (CCB), diuretics (DIU), angiotensin converting enzyme inhibitors (ACEI), angiotensin II receptor blockers (ARB), and beta blockers (BB). Centrally acting agents (CAA) and vasodilators (VAS) are used sparingly. Clients’ pharmacological management was frequently initiated with monotherapy (57.6%), of which CCB accounted for 77.2% of the prescriptions followed by DIU (10.5%). Dual- and three-drug therapies are also used in initiating management. Among the CCB, Nifedipine (71.4% / 57.303) is the most prescribed and bendrofluazide (94.1% / 83.78) is the most prescribed among the DIU. Aspirin 44 (46.8%) was the most prescribed non-AHA. The target or goal blood pressure (BP) for HPT clients from World Health Organization/International Society of Hypertension (WHO/ISH) and European Society of Hypertension/European Society of Cardiology (ESH/ESC) guidelines is <130/85 mmHg and that of the Ghana Standard Treatment Guidelines (GSTG) of the Ministry of Health (MOH) of Ghana is < 140/ 90 mmHg. Based on these criteria BP control rates are 42% and 62% respectively. In conclusion, the AHA in use at the HPT/DM Clinic of the KNUST Hospital and prescription pattern are in accordance with that of the international and national guidelines.

Source: KNUST
Pharmacotoxicological Assessment of Alchornea Cordifolia Leaf Extract

There are several reports on the biological actions of Aichomea cordifolia (Schumach. & Thonn.) MQII.Arg (Euphorbiaceae) but little knowledge on the potential toxicity of the plant The constituents of the alcoholic leaf extract of Aichomea cordifolia were verified and the total leaf extract was tested on rats and mice for possible toxicity. The effect of Aichomea cordifolia was also studied on the guinea pig ileum. The presence of tannins, terpenoids, flavonoids, anthracene glycosides and saponins was confirmed but alkaloids and phytosterols were not detected in the ' extract. The crude extract (0.5 mg/ml - 4 mg/mi) caused a concentration-dependent inhibition of acetylcholine and histamine-induced contractions on the isolated guinea- pig ileum. The antagonism appeared competitive as there was a rightward shift of the concentration-response curves with no significant depression of the maximum response. Daily administration of the crude extract (250 - 2000 mg/kg) for two weeks did not cause any significant changes in haematological parameters in both rats and mice. However, there was a dose-dependent increase (P< 0.05) in the number of neutrophils in rats. Lymphocyte numbers in treated rats decreased. There were no significant changes in the relative organ weights of treated rats or mice compared to control. Hepatic function, renal function and total proteins were not affected by the treatment. Histopathologicai examination of the liver and kidney did not show changes in organ architecture at 250mg/kg and 500mg/kg. However, early signs of liver injury were observed in rats treated with 1000mg/kg and 2000mg/kg. This observation was not accompanied by loss of hepatic function as observed in the pentobarbitone sleeping time experiment. The study has shown that the alcoholic extract of Aichomea cordifolia is relatively non toxic in both rats and mice, but the liver damage observed calls for caution in the use of Aichomea cordifolia for long periods especially at high doses. The inhibitory effects of Aichomea cordifolia on acetylcholine and histamine-induced contractions of the isolated guinea pig ileum may partly explain the usefulness of Aichomea cordiflia in the management of gastrointestinal disorders.

Source: KNUST
Phase behaviour of oat b-glucan/sodium caseinate mixtures varying in molecular weight

The isothermal phase behaviour at 5 C of mixtures of sodium caseinate and oat b-glucan isolates varying in molecular weight (MW) was investigated by means of phase diagram construction, rheometry, fluorescence microscopy and electrophoresis. Phase diagrams indicated that the compatibility of the b-glucan/ sodium caseinate system increases as b-glucan MW decreases. Images of mixtures taken at various biopolymer concentrations revealed phase separated domains. Results also revealed that at the state of thermodynamic equilibrium, lower MW samples yielded considerable viscosity in the mixture. At equivalent hydrodynamic volume of b-glucan in the mixtures, samples varying in molecular weight exhibited similar flow behaviour. A deviation dependent on the protein concentration was observed for the high MW sample in the concentrated regime due to the size of b-glucan aggregates formed. Results demonstrate that by controlling the structural features of b-glucan in mixtures with sodium caseinate, informed manipulation of rheological properties in these systems can be achieved.

Source: KNUST