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Ethnopharmacological Relevance. Development of resistance to antimalarial drugs by Plasmodium falciparum is still rampant, and there is an urgent need for novel drugs to either standalone or to partner artemisinin for treatment of malaria. Traditionally, plants have, over the years, been a good source of antimalarial drugs. Efficacy and safety of such plants need to be scientifically authenticated. Aims, Materials, and Method. This study investigated the in vitro antiplasmodial activity, cytotoxicity, and genotoxicity of aqueous extracts of Acanthospermum hispidum DC, Alstonia boone (De Wild), Cocos nucifera L, Cymbopogon citratus (DC.) Stapf, Morinda lucida Benth, Psidium guajava, Phyllanthus niruri L, and Senna siamea Lam. Results. Five out of the eight plants, A. boonei stem bark, S; siamea Lam root, M. lucida Benth leaves, P. niruri, and A. hispidum DC whole plants, showed varying degrees of antiplasmodial activity against the asexual stage of the parasite. The most active extract against chloroquine-sensitive (3D7) and chloroquine-resistant (Dd2) P. falciparum strains is the A. hispidum extract which yielded a mean inhibitory concentration at 50% (IC50) of 3.66 µg/ml and 3.71 µg/ml for 3D7 and Dd2, respectively. This was followed by S. siamea Lam with 3.95 µg/ml for 3D7 and 4.47 µg/ml for Dd2. The IC50 values of the A. boonei extract against 3D7 and Dd2 P. falciparum parasites were 5.13 µg/ml and 3.62 µg/ml, respectively. For the M. lucida Benth extract, the least IC50 value was 6.46 µg/ml. All five extracts exhibited dose-dependent antiplasmodial activity. Assessment of the genotoxic effects the A. hispidum extract by the comet assay revealed substantial damage to P. falciparum DNA. Conclusion. This study demonstrates that the crude extract of A. hispidum DC, one of the plants used traditionally to treat malaria, inhibits the growth of P. falciparum in vitro and could be a potential source of antimalarial drug. The report has highlighted genotoxic and cytotoxic effects of the selected plant extracts on human leukocytes as well.

Trypanosomiasis, leishmaniasis, and malaria are protozoan infections of public health importance with thousands of new cases recorded annually. Control of these infection(s) with existing chemotherapy is limited by drug toxicity, lengthy parenteral treatment, affordability, and/or the emergence of resistant strains. Medicinal plants on the other hand are used in the treatment of various infectious diseases although their chemical properties are not fully evaluated. In this study, we screened 112 crude extracts from 72 selected Ghanaian medicinal plants for anti-Trypanosoma, anti-Leishmania, and anti-Plasmodium activities in vitro and investigated their mechanisms of action. Twenty-three extracts from 20 plants showed significant antiprotozoan activity against at least 1 of 3 protozoan parasites screened with IC50 values less than 20 μg/ml. Eleven extracts showed high anti-Trypanosoma activity with Bidens pilosa whole plant and Morinda lucida leaf extracts recording the highest activities. Their IC50 (selectivity index [SI]) values were 5.51 μg/ml (35.00) and 5.96 μg/ml (13.09), respectively. Nine extracts had high anti-Leishmania activity with Annona senegalensis and Cassia alata leaf extracts as the most active. Their IC50 (SI) values were 10.8 μg/ml (1.50) and 10.1 μg/ml (0.37), respectively. Six extracts had high anti-Plasmodium activity with the leaf and stem-bark extracts of Terminalia ivorensis recording the highest activity. Their IC50 (SI) values were 7.26 μg/ml (129.36) and 17.45 μg/ml (17.17), respectively. Only M. lucida at 25 μg/ml induced significant apoptosis-like cell death in Trypanosoma parasites. Anti-Leishmania active extracts induced varying morphological changes in Leishmania parasites such as multiple nuclei and/or kinetoplast, incomplete flagella division, or nuclear fragmentation. Active extracts may be potential sources for developing new chemotherapy against these infections.

Background: The leaves of Pergularia daemia Forsk (family Asclepidaceae) provide alternative plant-based treatments for the management of diabetes mellitus and diarrhoea in both humans and indigenous poultry species like the Guinea fowls (Numida meleagris). However, no scientific investigations to validate its usefulness in Ghana have been established. This study therefore sought to investigate the anti-hyperglycaemic activity of the 70 % ethanolic extract of P. daemia using streptozotocin (STZ)-induced diabetic male Sprague–Dawley rats. Additionally, the antioxidant and antimicrobial properties of the extract were investigated. Methods: The total phenolic content, total flavonoids content, radical scavenging activity and reducing power assays were estimated using Folin–Ciocalteu method, aluminium chloride colorimetric assay, Fe3+ reduction assay and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assays, respectively. Results: The results showed that P. daemia extract caused anti-hyperglycaemic activity in the STZ-induced rats at doses of 30, 60 and 90 mg/kg body weight with significant reduction in blood glucose levels. The phytosterols, saponins, phenols, alkaloids, tannins and triterpenes found in the extract may be responsible for the observed anti-hyperglycaemia and antioxidant activities. The extract also showed antimicrobial activity against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus and Bacillus subtilis. Conclusions: These findings justify the folkloric use of P. daemia as an anti-diabetic and antibacterial agents for susceptible species.

A prospective randomised double blind parallel controlled trial was conducted to evaluate the safety and clinical effectiveness of a standardised Ghanaian polyherbal product EAF-2011 comprising: Alchornea cordifolia, Eugenia caryophyllata, Psidium guajava, Tridax procumbens and Zanthoxylum zanthoxyloides, used in the management of skin diseases. A total number of 84 participants aged between 8 and 45 years who were clinically diagnosed with superficial mycoses were recruited into the study and followed up for 4 months. Participants were randomised to receive 2%, 5% or 10% (w/w) concentrations of the finished herbal product or the control treatment of Whitfield ointment. Primary efficacy outcome (complete cure): defined as total signs and symptoms score (TSSS) of zero and where applicable mycological cure also defined as a negative mycological culture and microscopic examination was achieved by 30.0%, 34.78%, 75.0% and 91.30% of the control, 2%, 5% and 10% (w/w) EAF-2011 treatments respectively. Safety analyses using urine, biochemical and haematological parameters were normal at the end of the study. Also, no adverse reactions were recorded during the study. The study thus showed all the treatments to be safe and effective for the management of dermatophytes with 10% (w/w) finished herbal product being the most effective treatment.

Benign prostatic hyperplasia (BPH) is an enlargement of the prostate. The study aimed at validating the use of freeze-dried Croton membranaceus ethanolic root extract for BPH management. Thirty-three patients were observed before and after 3-month administration of 20 mg t.i.d orally. The International Prostate Symptom Score (IPSS), and the International Index of Erectile Function (IIEF) questionnaires were used. Total/free PSA (tPSA, fPSA), renal, liver function, lipid tests, and ultrasonographic imaging were performed. Thirty (30) patients (66 ± 11 years) completed the study. IPSS results showed 37% had severe, 40% moderate, and 23% mild symptoms before; 57% and 43% had moderate and mild symptoms, respectively, after treatment. IIED of patients’ results showed 30% with severe, 40% moderate, 24% mild-moderate, 3% mild, and 3% no erectile dysfunction before treatment and 20% severe, 43% moderate, and 37% mild-moderate dysfunction, after treatment. Quality of life (QoL) improved (P=0.001). Significant but non-pathological increases in total and indirect bilirubin as well as apolipoprotein A occurred. Mean tPSA reduced from 27.9 ± 19.0 to 16.2 ± 11.8 ng/mL (P=0.002); fPSA from 6.1 ± 4.8 to 3.9 ± 2.9 ng/mL (P=0.045); and prostate volume from 101.8 ± 41.3 to 54.5 ± 24.8 cm3 (P=0.023). C. membranaceus shrinks the prostate and improves QoL.

Trypanosomiasis, leishmaniasis, and malaria are protozoan infections of public health importance with thousands of new cases recorded annually. Control of these infection(s) with existing chemotherapy is limited by drug toxicity, lengthy parenteral treatment, affordability, and/or the emergence of resistant strains. Medicinal plants on the other hand are used in the treatment of various infectious diseases although their chemical properties are not fully evaluated. In this study, we screened 112 crude extracts from 72 selected Ghanaian medicinal plants for anti-Trypanosoma, anti-Leishmania, and anti-Plasmodium activities in vitro and investigated their mechanisms of action. Twenty-three extracts from 20 plants showed significant antiprotozoan activity against at least 1 of 3 protozoan parasites screened with IC

The strong anti-trypanosomal active compound, molucidin, contains a spirolactone tetracyclic iridoid skeleton and is isolated from Morinda lucida as an enantiomer of oruwacin, which is isolated from the same plant. To confirm the absolute configuration of molucidin, we prepared single crystals of molucidin for X-ray analysis. The absolute configuration of the afforded single crystal was determined by X-ray crystallography using a Cu radiation source. X-ray diffraction data were collected at 93 K in the 2 θ range 7.468–134.99° and analyzed using the SHELXL-2014 program. The corresponding chiral quaternary carbon atoms in molucidin were unambiguously determined as 1 R , 5 S , 8 S , 9 S , and 10 S . Notably, both enantiomers of a single molecule, molucidin and oruwacin, with a rigid structure have been isolated from the same plant species. The biosynthetic pathway for the formation of molucidin is also discussed on the basis of the absolute configuration. Our results for the first time support for structural elucidation of tetracyclic iridoids using X-ray analysis.

Background: The widespread use of herbal medicines in recent years means that issues concerning their quality, safety and efficacy need to be answered. In the current study, the polyherbal formulation EAF-2011 used in the Centre for Scientific Research into Plant Medicine, Mampong- Akwapemfor the management of superficial mycoses was evaluated for its quality and safety. Aim: The study sought to evaluate the quality and safety of the product in the management of superficial mycoses. Method: The method of standardisation using the basic phytochemical screening and the thin layer chromatography procedures was used. The stability was also assessed using the thin layer chromatography, an antimicrobial assay and the physicochemical properties of the product. A safety evaluation of the product was also performed using a skin sensitisation and chronic toxicity test in male Sprague-Dawley rats. Results: The product demonstrated stability during the study period of one year as results obtained from the thin layer chromatography, physicochemical and biological assay did not indicate any significant change in characteristics. Alkaloids, phenols, flavonoids, sterols and triterpenes were detected in the product. Three spots obtained by the thin layer chromatography were shown to be ideal for use as analytical markers for the product. Haematological, biochemical, urine and histopathological data at the end of the study did not indicate any adverse effect from the herbal treatments. Conclusion: The study thus showed the ointment to be safe for the management of superficial mycoses. Key words: Analytical markers, chronic toxicity, polyherbal formulation, safety, standardisation, superficial mycoses

Trypanosoma brucei parasites are kinetoplastid protozoa that devastate the health and economic well-being of millions of people in Africa through the disease human African trypanosomiasis (HAT). New chemotherapy has been eagerly awaited due to severe side effects and the drug resistance issues plaguing current drugs. Recently, there has been an emphasis on the use of medicinal plants worldwide. Morinda lucida Benth. is a popular medicinal plant widely distributed in Africa, and several research groups have reported on the antiprotozoal activities of this plant. In this study, we identified three novel tetracyclic iridoids, molucidin, ML-2-3, and ML-F52, from the CHCl 3 fraction of M. lucida leaves, which possess activity against the GUTat 3.1 strain of T. brucei brucei . The 50% inhibitory concentrations (IC 50 ) of molucidin, ML-2-3, and ML-F52 were 1.27 μM, 3.75 μM, and 0.43 μM, respectively. ML-2-3 and ML-F52 suppressed the expression of paraflagellum rod protein subunit 2, PFR-2, and caused cell cycle alteration, which preceded apoptosis induction in the bloodstream form of Trypanosoma parasites. Novel tetracyclic iridoids may be promising lead compounds for the development of new chemotherapies for African trypanosomal infections in humans and animals.

Background: The interplay between Epstein-Barr virus infection, malaria, and endemic Burkitt’s Lymphoma is not well understood. Reports show diminished EBV-specific Th1 responses in children living in malaria endemic areas and deficiency of EBNA1-specific IFN-γ T cell responses in children with endemic Burkitt’s Lymphoma (eBL). This study, therefore, examined some factors involved in the loss of EBNA-1-specific T cell responses in eBL. Methods: T-cell subset frequencies, activation, and IFN-γ- or IL-4-specific responses were analyzed by flow-cytometry. Plasma cytokine levels were measured by ELISA. Results: CD4+ and CD8+ cells in age- and sex-matched healthy controls (n = 3) expressed more IFN-γ in response to all immunostimulants than in pediatric endemic BL (eBL) patients (n = 4). In healthy controls, IFN-γ expression was higher than IL-4 expression, whereas in eBL patients the expression of IL-4 by CD4+ cells to EBNA-1 was slightly higher than IFN-γ. Moreover, the blood levels of TNF-α was significantly lower (p = 0.004) while IL-10 was significantly higher (p = 0.038), in eBL patients (n = 21) compared to controls (n = 16). Additionally, the frequency of CD4+CD25hi+ T cells was higher in both age-matched acute uncomplicated malaria (n = 26) and eBL (n = 14) patients compared to healthy controls (n = 19, p = 0.000 and p = 0.027, respectively). Conclusion: The data suggest that reduced Th1 response in eBL might be due to increased levels of IL-10 and T reg cells.

Alnus japonica Steud is a tree that grows in damp areas of mountain valleys and has been used as a traditional medicine in Asia. We investigated the antiproliferative activity of hirsutanone (Hir) and oregonin (Ore) in human cancer cell lines and elucidated their mechanisms of action. A cytotoxicity study using a panel of 12 human cancer and 4 normal cell lines indicated that Hir exhibited potent antiproliferative activity against 4 leukemia (Jurkat, U937, THP-1, and HL-60) and 2 colon cancer cell lines (HCT-15 and Colo205). Although Ore suppressed the cell growth of Jurkat and THP-1, its inhibitory potency was weaker than that of Hir. The IC50 values of Hir and Ore in Jurkat were 11.37 μM and 22.16 μM, respectively. Further analysis on Jurkat cells demonstrated that Hir caused a sequence of events involved in apoptosis, including nuclear morphological changes and accumulation of cells with sub-G1 DNA content. Hir led to the cleavage of poly(ADP-ribose) polymerase (PARP) and activation of caspase-3, -8, and -9. In addition, Hir-induced PARP cleavage was completely abolished by specific inhibitors to these caspases. Our data suggested that Hir is a potent antiproliferative compound against the 4 leukemia cell lines and the 2 colon cancer cell lines tested. Furthermore, Hir exerts antiproliferative actions via caspase-dependent apoptotic cell death.

Human African trypanosomiasis (HAT), commonly known as sleeping sickness has remained a serious health problem in many African countries with thousands of new infected cases annually. Chemotherapy, which is the main form of control against HAT has been characterized lately by the viewpoints of toxicity and drug resistance issues. Recently, there have been a lot of emphases on the use of medicinal plants world-wide. Morinda lucida Benth. is one of the most popular medicinal plants widely distributed in Africa and several groups have reported on its anti-protozoa activities. In this study, we have isolated one novel tetracyclic iridoid, named as molucidin, from the CHCl3 fraction of the M. lucida leaves by bioassay-guided fractionation and purification. Molucidin was structurally elucidated by (1)H and (13)C NMR including HMQC, HMBC, H-H COSY and NOESY resulting in tetracyclic iridoid skeleton, and its absolute configuration was determined. We have further demonstrated that molucidin presented a strong anti-trypanosomal activity, indicating an IC50 value of 1.27 μM. The cytotoxicity study using human normal and cancer cell lines indicated that molucidin exhibited selectivity index (SI) against two normal fibroblasts greater than 4.73. Furthermore, structure-activity relationship (SAR) study was undertaken with molucidin and oregonin, which is identical to anti-trypanosomal active components of Alnus japonica. Overlapping analysis of the lowest energy conformation of molucidin with oregonin suggested a certain similarities of aromatic rings of both oregonin and molucidin. These results contribute to the future drug design studies for HAT.

Despite remarkable advances in combination antiretroviral therapy (cART), human immunodeficiency virus type 1 (HIV-1) infection remains incurable due to the incomplete elimination of the replication-competent virus, which persists in latent reservoirs. Strategies for targeting HIV reservoirs for eradication that involves reactivation of latent proviruses while protecting uninfected cells by cART are urgently needed for cure of HIV infection. We screened medicinal plant extracts for compounds that could reactivate the latent HIV-1 provirus and identified a procyanidin trimer C1 derived from Theobroma cacao as a potent activator of the provirus in human T cells latently infected with HIV-1. This reactivation largely depends on the NF-κB and MAPK signaling pathways because either overexpression of a super-repressor form of IκBα or pretreatment with a MEK inhibitor U0126 diminished provirus reactivation by C1. A pan-PKC inhibitor significantly blocked the phorbol ester-induced but not the C1-induced HIV-1 reactivation. Although C1-induced viral gene expression persisted for as long as 48 h post-stimulation, NF-κB-dependent transcription peaked at 12 h post-stimulation and then quickly declined, suggesting Tat-mediated self-sustainment of HIV-1 expression. These results suggest that procyanidin C1 trimer is a potential compound for reactivation of latent HIV-1 reservoirs.

Background: Borassus aethiopum Mart (Family Arecaceae), commonly known as the African Fan Palm, is a tropical plant species found widely across Africa, and used globally for both medicinal and non-medicinal purposes. In this study, the anti-oxidant, anti-microbial and anti-inflammatory activities of an ethanolic extract of the fruit of Borassus aethiopum was investigated. Methods: The Carrageenan induced foot edema model in chicks was used to investigate the anti-inflammatory activity of an ethanolic extract of the seed endocarp cotyledon. For the anti-oxidant activity determination, three assays were employed; namely, the total anti-oxidant capacity assay, the 2, 2-diphenyl- 1-picrylhydrazyl (DPPH) scavenging assay and the Folin-Ciocalteau’s assay for total phenols. For the anti-microbial activity, the agar diffusion method was used. Phytochemical analysis to determine the types of secondary metabolites present was also conducted on the plant extract. Results: The phytochemical screening showed the presence of alkaloid, tannins, saponins, steroids, carbohydrates triterpenoids and phenols. A dose dependent reduction in edema was observed when the extract was compared with Diclofenac and Dexamethasone. The extract had an EC50 of 13.49 µg/ml DPPH scavenging activity, which is excellent when compared to the reference ascorbic acid of 140.00 µg/ml. Thus the extract was about 10 times more potent than the ascorbic acid. Conclusion: The anti-microbial assay revealed activity against the gram positive bacteria Staphylococcus aureus and Bacillus subtilis. The results obtained showed that Borassus aethiopum has anti-inflammatory and significant anti-oxidant properties, which are dose and concentration dependent respectively.

The crude extract of Alnus japonica bark exhibited a strong effect on the growth of Trypanosoma brucei. Subsequent chromatographic separation resulted in the isolation of two novel diarylheptanoids, known as alnuside C (2) and alnuside D (3), and three known compounds, 1-(3,4-dihydroxyphenyl)-7-(4-hydroxyphenyl)-heptan-3(R)-O-β-D-glucopyranoside (1), oregonin (4) and hirsutanone (5). The structures of the isolates were elucidated based on the use of extensive spectroscopic and chemical methods. Among the isolated diarylheptanoids, oregonin (4) (a major component of plant bark) and hirsutanone (5) exhibited potent in vitro inhibitory activity against T. brucei growth in the bloodstream with IC50values of 1.14 and 1.78 μM, respectively. We confirmed that oregonin (4) and hirsutanone (5) were not toxic to human normal skin fibroblast cells (NB1RGB) and colon cancer cells (HCT-15) at a concentration of 50 μM; however, lower levels of toxicity were observed for leukemia cells. To determine the structure activity relationships of the isolated components, we performed Conformation Search and found that the 3-oxo function of the heptane chain in the diarylheptanoid molecule is required for their trypanocidal activity.

A mutation-specific polymerase chain reaction method was used to estimate the proportion of pyrimethamine-resistant parasites in 101 children reporting with malaria at the hospital in Ifakara, a town in southern Tanzania. The method is based on the observation that a point mutation (Asn-108) in the dihydroifolate reductase gene confers resistance to pyrimethamine. Twenty-eight percent of the examined 101 children had pyrimethamine-resistant parasites, 65% had pyrimethamine-sensitive parasites with the wild-type Ser-108 codon, and 9% had both alleles, suggesting a mixed infection. None of the 21 children with clinical malaria had pyrimethamine-resistant parasites. Currently, sulfadoxine-pyrimethamine is considered a potential first-line drug for malaria treatment in most African countries. We suggest that although sulfadoxine-pyrimethamine could still be effective against chloroquine-resistant malaria in this area, its judicious use is important so as to minimize the spread of resistance.

BackgroundCerebral malaria (CM) is responsible for most of the malaria-related deaths in children in sub-Saharan Africa. Although, not well understood, the pathogenesis of CM involves parasite and host factors which contribute to parasite sequestration through cytoadherence to the vascular endothelium. Cytoadherence to brain microvasculature is believed to involve host endothelial receptor, CD54 or intercellular adhesion molecule (ICAM)-1, while other receptors such as CD36 are generally involved in cytoadherence of parasites in other organs. We therefore investigated the contributions of host ICAM-1 expression and levels of antibodies against ICAM-1 binding variant surface antigen (VSA) on parasites to the development of CM.Methodology/principal findingsPaediatric malaria patients, 0.5 to 13 years were recruited and grouped into CM and uncomplicated malaria (UM) patients, based on well defined criteria. Standardized ELISA protocol was used to measure soluble ICAM-1 (sICAM-1) levels from acute plasma samples. Levels of IgG to CD36- or ICAM-1-binding VSA were measured by flow cytometry during acute and convalescent states. Wilcoxon sign rank-test analysis to compare groups revealed association between sICAM-1 levels and CM (p0.05). Median levels of antibodies to CD36-binding VSAs were also comparable between acute and convalescent samples within any patient group. Median levels of antibodies to ICAM-1-binding VSAs were however significantly lower at admission time than during recovery in both groups.Conclusions/significanceHigh levels of sICAM-1 were associated with CM, and the sICAM-1 levels may reflect expression levels of the membrane bound form. Anti-VSA antibody levels to ICAM-binding parasites was more strongly associated with both UM and CM than antibodies to CD36 binding parasites. Thus, increasing host sICAM-1 levels were associated with CM whilst antibodies to parasite expressing non-ICAM-1-binding VSAs were not.

The antihyperglycaemic and antioxidant activities of a Ghanaian medicinal plant namely Adenia lobata Engl (Passifloraceae), used to treat diabetes mellitus in traditional medicine, was investigated. The dried stem powder of A. lobata was successively extracted by Soxhlet with petroleum ether and 70% ethanol to obtain the crude petroleum ether (PEAL: yield =1.1w/w %) and ethanol (EEAL: yield = 5.4 w/w %) extracts. The extracts were assessed for their antihyperglycaemic and antioxidant activities. The antihyperglycaemic activity of PEAL and EEAL were determined in streptozotocin-induced diabetic rats (70 mg/kg body weight). Five groups of diabetic rats were given 150, 300 and 600 mg/kg body weight of PEAL and EEAL orally once daily for 20 days. Glibenclamide (5 mg/kg body weight) was used as positive control while distilled water (5 ml) acted as the normal diabetic control. The blood glucose levels were monitored initially for 6 hours and subsequently over 24 days. Both extracts exhibited statistically significant (p< 0.001) antihyperglycaemic activity throughout the study period, with EEAL showing the greatest activity. The antioxidant properties of the petroleum ether and ethanol extracts of A. lobata (PEAL and EEAL) were evaluated using five assays; total phenolic content, total antioxidant capacity, reducing power, DPPH scavenging effect and lipid peroxidation activity. In all these assays, the antioxidant properties increased with increasing concentration of the extracts.Key words: Antihyperglycaemic, antioxidant, diabetes, Adenia lobata

The in vivo anti-inflammatory and analgesic activities of the crude ethanol extract and chemical constituents of Clausena anisata roots were investigated. The crude extract, which was devoid of any visible acute toxicity, displayed significant anti-inflammatory effect at the dose of 1000 mg/kg (p.o.) when assessed using the carrageenan-induced oedema model. In the acetic acid-induced writhing and hot plate tests, it produced a very significant ( p < 0.001), dose-dependent analgesic effect, with maximum analgesic activity of 72.1% at 1000 mg/kg (p.o.). Phytochemical analysis of the crude extract resulted in the isolation of four coumarins (anisocoumarin B, osthol, imperatorin and xanthotoxol) and a carbazole alkaloid, heptaphylline. Among the isolated compounds, osthol and anisocoumarin B produced the highest anti-inflammatory activity at 9 mg/kg (p.o.): slightly better than the positive control, indomethacin. Except for xanthotoxol, all the isolated compounds administered at 6 mg/kg (p.o.) produced significant analgesic activity and higher than diclofenac; with heptaphylline being the most potent (48.7%). The analgesic activity of anisocoumarin B (50.4%) was the highest among the isolates tested and the standard, tramadol, in the hot plate test. The nonselective opioid receptor antagonist, naloxone, abolished the analgesic effect of the crude extract and the tested isolates (anisocoumarin B and xanthotoxol) in the hot plate test suggesting an effect via the central opioidergic system. These findings provide the scientific basis for the use of C. anisata roots in traditional medicine as anti-inflammatory and analgesic agents.

A cross-sectional pilot study of hookworm infection was carried out among 292 subjects from 62 households in Kintampo North, Ghana. The overall prevalence of hookworm infection was 45%, peaking in those 11–20 years old (58.5%). In children, risk factors for hookworm infection included coinfection with malaria and increased serum immunoglobulin G reactivity to hookworm secretory antigens. Risk factors for infection in adults included poor nutritional status, not using a latrine, not wearing shoes, and occupation (farming). Although albendazole therapy was associated with an overall egg reduction rate of 82%, 37 subjects (39%) remained infected. Among those who failed therapy, treatment was not associated with a significant reduction in egg excretion, and nearly one-third had higher counts on repeat examination. These data confirm a high prevalence of low-intensity hookworm infection in central Ghana and its association with poor nutritional status. The high rate of albendazole failure raises concern about emerging resistance.

In higher plants the promoter elements of pol II- and pol III-transcribed U-snRNA genes are identical, comprising a -30 TATA box and an upstream sequence element, USE. The USE and TATA are centred approximately four and three helical DNA turns apart in pol II and pol III genes, respectively, and it is this difference in the element spacing that determines the RNA polymerase specificity of the gene. In this study we have analyzed the effect of spacing mutations on activity of Arabidopsis U2 and U6 genes in transfected protoplasts of Nicotiana plumbaginifolia and in stably transformed tobacco. In the pol III-transcribed U6 gene the insertions and deletions of either odd or even numbers of half helical turns completely inactivate transcription in transfected protoplasts, consistent with the high conservation of the element spacing found in all plant U-snRNA genes. Surprisingly, while insertions of 50 base pairs (bp) or more into the spacer of the pol II-specific U2 gene inactivate transcription, a deletion of 5 bp or insertions of as much as 20 bp decrease transcription by only 40 to 70%. This relaxed requirement for the conserved element spacing is only seen in transfected protoplasts since the same mutant U2 genes are not transcribed in stably transformed tobacco when transcription takes place from the chromosome. The results provide some clues about possible factor interactions at the promoters of plant U-snRNA genes and also offer an example of major differences in transcription between transiently and stably transformed cells.

Objectives: To investigate Toxoplasma infection among pregnant women in relation to exposure to infection risk, age and pregnancy-related risk factors. Design and Methods: This cross-sectional study involved 294 pregnant women attending ante-natal clinic in Accra who consented to participate. Personal and Toxoplasma infection risk related data were obtained by questionnaire interviews. Venous blood was safely drawn from each participant and spun to obtain sera. Each of the 159 randomly selected serum samples was tested for specific anti-Toxoplasma (anti-T. gondii) antibodies IgG, IgA and IgM using a commercial ELISA kit (Calbiotech Inc., CA). ELISA results were correlated with exposure to possible infection risk factors as well as age and pregnancy-related risk factors. Results: The 159 women aged 15-40 years in their first, second and third trimesters, numbered 29, 70 and 60, respectively. An overall anti-T. gondii antibodies IgG, IgA and IgM seroprevalence of 92.5% (147/159) was recorded, with 4.1% (6/147) of them having anti- IgG only. The remaining 88.7% (141/159) had anti- Toxoplasma antibodies IgG, IgA and IgM in various combinations and consisted of 17.7% (25/141) in their first, 44.0% (62/141) in their second, and 38.3% (54/141) in their third, trimesters. Twelve women (7.6%) were seronegative for all 3 antibodies Conclusions: Seroprevalence was high among the women and exposure to contact with cats’ faeces was found to be the major T. gondii infection risk factor. Age and pregnancy-related risk factors did not have association with T. gondii infection within the limitations of this study.

Schistosomiasis has been a major public health problem especially in developing countries, where access to potable water is generally limited. Its control calls for a search for various interventions that would not only target the causative agent and human behavior, but also the snail intermediate host. This study explored the possibility of using bioactive factors from naturally occurring crude or semi-processed products including some plant parts and vegetables to control the Bulinus globosus intermediate host. In all, five (25%) of the test materials in decreasing order (pawpaw > cabbage > short banana > sugarcane > sweet orange) acted as statistically significant arrestants for the adults, but four (20%) of them in decreasing order (cabbage > unripe pawpaw > sugarcane > ripe tomato) were arrestants for the juveniles at (p short banana > sugarcane > cabbage and cabbage > palm > sugarcane > unripe pawpaw). However, mango tree bark, neem tree bark, unripe mango, onion and cassava stem acted as significant repellents to both adult and juvenile snails. The identified attractants and arrestants for Bulinus globosus, pawpaw and cabbage, may be useful in its chemical manipulations especially as molluscicides in controlling the intermediate host snails. Keywords : Schistosomiasis, snail, Bulinus globosus, chemoresponses, natural products

Urinary schistosomiasis is of great public health importance in developing countries. It has adverse economic and health implications on residents living in endemic areas. Various factors including human behaviour are known to play key role in the transmission of the disease. The knowledge of the levels of risk of infection of urinary schistosomiasis and people’s perception will be an important tool in its control. The study determined the prevalence of urinary schistosomiasis and the risk of infection in some communities near the Weija lake in the Ga District. It assessed the knowledge base of the subjects on the disease and its impact on transmission. Data were collected on demographic variables, some behavioural activities in water bodies, knowledge base on the disease and sanitary facilities. Urine samples were analysed using the centrifugation technique. The percentage prevalence for Mahem and Galilea were 58% and 49%, respectively. The difference in prevalence was insignificant; 0.09 (-0.04, 0.21; P < 0.426). Bloody urine was associated with high risk of infection; OR of 4.55 (2.82, 7.36); P < 0.001. Subjects with primary level of education and invariably below 26 years of age had about two times the risk of infection; OR of 2.12 (1.13, 3.97); P < 0.02. The communities had 52% prevalence of urinary schistosomiasis. Frequent contacts and use of the infested lake were associated with infection. Educational intervention alone may not be effective in the control of the disease. The use of an integrated approach should be given favourable consideration.

In a community based study at Legon in 1997, a valuation method was used to assess the willingness of students on study leave to pay a percentage premium of their income towards a National Health Insurance Scheme (NHIS). Thirty-five percent of the respondents were aged 30-40 years, 97% were males, 45% were resident in Accra, 17% in Kumasi and 12% in Cape Coast. Respondents were 84% in formal public employment with 44% majority as teachers. Their monthly income was distributed as 33% earned below currency 200,000, 50% between currency 200,000-currency 400,000 and 7% above currency 400,000. More than 74% were willing to contribute to the scheme with 38% and 37% willing to pay 1% and 2 of their income as monthly premium respectively. Those willing to pay 2% premium, 14 (n=33) earned below currency 200,000, 18 (n=50) between currency 200,000-currency 400,000, and 5 (n=17) above currency 400,000. Malaria was the commonest disease with 86% incidence, however 30%of respondents revealed they did not spend money on hospital services except 39% who spent currency 20,000-currency 100,000 on hospital laboratory services. Over 65% of respondents indicated they self financed their health expenditure. The premium level was found to be influenced positively by financier, sex, age, income, and negatively by health expenditure, but not occupation. In an elite community with inadequate infrastructure and water supply problems but probably with better personal hygiene and sanitation, although respondents hardly spend on health services they were willing to contribute 2% of their incomes as premium towards an insurance scheme.

Rapid assessment of a National Tuberculosis Control Programme (NTP) that provides free treatment for TB patients was conducted at Koforidua in eastern Ghana. In 1997, 540 people were clinically suspected with TB and 148 tested positive by laboratory diagnosis. Likewise in the first quarter of 1998, 223 people were suspected and 25 tested positive. Thus, coverage rate increased from 45 in 1997 to 74.5 in 1998. TB incidence was highest (29.7%) in age group 31-40 years and lower (2.2%) in children below 10 years. More males (64%) had TB than females. In 1996, 196 pulmonary TB patients were receiving treatment at Koforidua Central Hospital (KCH). Outcome assessments revealed 40.6% were cured, 5.6% had treatment failure, 6.7% were transferred out, 1.1% died, but most 46.1% defaulted. Defaulters were mostly men (46.3%) and those residing in Koforidua suburbs (47.2%) but this was statistically insignificant. The treatment regimen was effective since most cases were new (70%) with few relapses and treatment failures, 1.2% each. Knowledge of the reason for defaulting is important for the success of the NTP programme.

Takanori Hori a, , Jacob Barnor b, , Tung Nguyen Huu c, , Osamu Morinaga , Akiko Hamano , Jerry Ndzinu a, , Angela Frimpong , Keren Minta-Asare , Mildred Amoa-Bosompem , James Brandful , John Odoom , Joseph Bonney , Isaac Tuffour , Baffour-Awuah Owusu , Mark Ofosuhene , Philip Atchoglo , Maxwell Sakyiamah , Richard Adegle , Regina Appiah-Opong , William Ampofo , Kwadwo Koram , Alexander Nyarko , Laud Okine , Dominic Edoh , Alfred Appiah , Takuhiro Uto , Yoshiyuki Yoshinaka , Shin Uota a, , Yukihiro Shoyama , Shoji Yamaoka a, * a Tokyo Medical and Dental University, Japan b Noguchi Memorial Institute for Medical Research, Ghana c Nagasaki International University, Japan d Centre for Plant Medicine Research, Ghana

The association between the clinical outcome of chloroquine treatment and mutations in the putative Plasmodium falciparum chloroquine resistance transporter (Pfcrt) gene at codon 76 and multidrug resistance gene 1 (Pf mdr1) at codon 86 were investigated among 406 children with uncomplicated malaria presenting at five sentinel health centres in Ghana. Presence of mutations in isolates taken at pre-treatment and on day of recurrence of parasites was detected using PCR followed by RFLP techniques. The prevalence of Pfcrt T76 mutants was 80% at Hohoe, 46% at Navrongo, 98% at Tarkwa, 61% at Sunyani and 46% at Yendi. The prevalence of the mutant Pfmdr1 at Hohoe, Navrongo, Tarkwa, Sunyani and Yendi were 78, 58, 95, 53 and 42%, respectively. Significant association between the Pfcrt mutation and treatment outcome was observed at Hohoe and Sunyani (p0.05), but not at Navrongo, Tarkwa or Yendi (p0.05). Similarly, a statistical significant association between Pfmdr1 86 and treatment failures was observed at Hohoe and Sunyani (p0.05) but not at the other three sites. A positive correlation was found between mutant Pfcrt prevalence only and treatment failures with a Spearman's rho-value of 0.872 and a p-value = 0.027. All parasite isolates from samples taken at recrudescence from patients with chloroquine treatment failures were found to have both Pfcrt and Pfmdr mutations.

Fetal hemoglobin has been implicated in the modulation of sickle cell crisis though it is functional during infancy.The purpose of this study was to determine the waning time of fetal hemoglobin (HbF) and its persistence in later life.Ninety infants aged 0-12 months, admitted at hospital, were tested for their HbF levels. Adult patients numbering 690 were also examined for their sickle cell status and a sickle positive patient of SS type with HbF had her family members recruited and their sickle cell types determined.The results revealed that HbF was highest (98%) at birth, decreasing at 5% per week till 6 months when it wane off. Ten infants aged 6-12 months had HbF persisting at a level of 10% or more. Adult patients examined showed proportions of their sickle cell types as AS forming 51%, AC 20%, SS 19%, and SC 10%. An SS adult patient with mild sickle cell crisis had an ASF father who had no crisis and a mother and brother with AS each who had severe crisis.These findings suggest that HbF wanes off during infancy but persist in some adults and may modulate crisis in these adults. This has implications in sickle cell management.

Under some circumstances, polymerase chain reaction (PCR) amplification of deoxyribonucleic acid (DNA) from Plasmodium may become necessary from infections for which only blood slides are available. Established methods used for DNA preparation do not work in that case. We have developed a reliable and controlled method for DNA preparation from malaria parasites on fixed and stained blood films. 162 slides from 2 different locations, some stored for at least one year, have been analysed by PCR amplification of the polymorphic loci for MSA1 and MSA2. In 92% of microscopically positive slides, a PCR product could be detected using material derived from thick blood films. When thin blood films with scanty parasitaemia were used, a PCR product could be obtained with only 71% of samples. In all unsuccessful cases, DNA preparation was the limiting factor, which was controlled for by amplification of a control human template.

Rapid assessment of a National Tuberculosis Control Programme (NTP) that provides free treatment for TB patients was conducted at Koforidua in eastern Ghana. In 1997, 540 people were clinically suspected with TB and 148 tested positive by laboratory diagnosis. Likewise in the first quarter of 1998, 223 people were suspected and 25 tested positive. Thus, coverage rate increased from 45 in 1997 to 74.5 in 1998. TB incidence was highest (29.7%) in age group 31-40 years and lower (2.2%) in children below 10 years. More males (64%) had TB than females. In 1996, 196 pulmonary TB patients were receiving treatment at Koforidua Central Hospital (KCH). Outcome assessments revealed 40.6% were cured, 5.6% had treatment failure, 6.7% were transferred out, 1.1% died, but most 46.1% defaulted. Defaulters were mostly men (46.3%) and those residing in Koforidua suburbs (47.2%) but this was statistically insignificant. The treatment regimen was effective since most cases were new (70%) with few relapses and treatment failures, 1.2% each. Knowledge of the reason for defaulting is important for the success of the NTP programme.

Health insurance becomes a viable alternative for financing health care amidst the high cost of health care. This study, conducted in 1997, uses a valuation method to assess the willingness of individuals from the working sector in Accra, Ghana, to join and pay premium for a proposed National Health Insurance Scheme (NHIS). Over 97%of the respondents agreed to join the scheme and 62. 8% were willing to contribute 2%of their income as premium. Respondents were mostly aged 30-50 years and 68% in the formal sector with 77% having monthly incomes ranging from currency 100,000 to currency 500,000 ($1=currency 2,400). Only 23.6% had their health care expenditure financed by their employers. Most, 83% indicated they visited hospitals more regularly than laboratories and a 14.5% of the irregular hospital visitors admitted spending over currency 100,000 per year on self-medication. Respondents revealed they spent on the average currency 100,000 and currency 50,000 per year for hospital and laboratory services respectively. The estimated individual health expenditure by biomedical methods was nearly currency 10,000 per month. Estimating individual health expenditure is necessary to set meaningful premiums and biomedical science as laboratory services provided could be a useful tool for such a purpose.

The concurrent use of herbal medicines and orthodox drugs, especially in the treatment and management of chronic ailments, may result in clinically significant herb-drug interactions. Bridelia ferruginea Benth (Euphorbiaceae) is a common medicinal plant with known anti-diabetic properties and has been reported to be taken alongside the orthodox medicine, metformin. The aim of this study was to investigate the effect of aqueous extract of B. ferruginea leaves on the pharmacokinetics of metformin in female Sprague-Dawley rats. Reconstituted freeze dried extract of B. ferruginea leaves (30 mg/kg), and metformin (7 mg/kg) were administered concurrently as a single dose to female Sprague-Dawley rats. Whole blood samples (1 ml) were aseptically withdrawn by tail bleeding at 1, 2, 4, 8, and 24 h after administration of the single dose for pharmacokinetics analyses. Concurrent administration of metformin and B. ferruginea significantly affected (P < 0.05) all the pharmacokinetics parameters of metformin except for the time to attain the maximum concentration (Tmax), which increased but insignificantly. Whereas the area under the curve, maximum whole blood concentration (Cmax) and half-life (T½) of metformin decreased significantly in the presence of B. ferruginea, the elimination rate constant (Kel), clearance (Cl), absorption rate constant (Ka), and volume of distribution (Vd) of metformin increased significantly in the presence of B. ferruginea. Therefore, in clinical practice, patients should be advised on the implication of concurrent administration of metformin and B. ferrruginea.

We have previously characterized the U2 small nuclear (sn) RNA gene family of Arabidopsis thaliana. To find out the structural features of upstream and downstream non-coding regions that are shared by different U-RNA genes in higher plants we have isolated the gene encoding a 125 nt-long U5 snRNA of Arabidopsis. Activity of the cloned gene was demonstrated in stably transformed tobacco calli and by transient expression in transfected protoplasts of Nicotiana plumbaginifolia. Southern analysis indicated that the Arabidopsis genome contains 8-9 copies of the U5 gene. Alignment of upstream non-coding regions revealed two elements conserved between all plant U-RNA genes characterized so far: the sequence RTCCCACATCG (-70/-80 region, 100% conservation) and the TATA homology around position -30. The coding regions in all genes are followed by the sequence CAN4-9AGTN (A/T)AA which may correspond to a termination and/or processing signal.