11 results
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2. Animal research ethics in Africa: is Tanzania making progress?
- Author
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Seth M and Saguti F
- Subjects
- Africa, Animals, Education, Professional standards, Government Regulation, Health Services Needs and Demand ethics, Humans, Tanzania, Animal Experimentation ethics, Ethics Committees, Research, Ethics, Research education
- Abstract
The significance of animals in research cannot be over-emphasized. The use of animals for research and training in research centres, hospitals and schools is progressively increasing. Advances in biotechnology to improve animal productivity require animal research. Drugs being developed and new interventions or therapies being invented for cure and palliation of all sorts of animal diseases and conditions need to be tested in animals for their safety and efficacy at some stages of their development. Drugs and interventions for human use pass through a similar development process and must be tested pre-clinically in laboratory animals before clinical trials in humans can be conducted. Therefore, animals are important players in research processes which directly and indirectly benefit animals and humans. However, questions remain as to whether these uses of animals consider the best interests of animals themselves. Various research and training institutions in Tanzania have established some guidelines on animal use, including establishing animal ethics committees. However, most institutions have not established oversight committees. In institutions where there may be guidelines and policies, there are no responsible committees or units to directly oversee if and how these guidelines and policies are enforced; thus, implementation becomes difficult or impossible. This paper endeavours to raise some issues associated with the responsible use of animals in research and training in Tanzania and highlights suggestions for improvement of deficiencies that exist in order to bridge the gap between what ought to be practised and what is practised., (© 2012 John Wiley & Sons Ltd.)
- Published
- 2013
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3. Animal research ethics in Africa: an overview.
- Author
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Nyika A
- Subjects
- Africa, Animal Experimentation legislation & jurisprudence, Animal Use Alternatives, Animal Welfare, Animals, Guidelines as Topic, Teaching, Animal Experimentation ethics, Ethics, Research
- Abstract
With research projects that use animals on the increase worldwide and in Africa in particular, animal research ethics should continue to be reviewed to improve the welfare of animals used in research. The welfare of animals used in research has gained attention globally that has led to the development of guidelines and in some instances national laws governing animal experimentation. Although there may not be empirical data on the existence or adequacy of national and/or institutional policies and guidelines on the use of animals in research in Africa, most African countries are not yet at the same level as developed countries. Consequently, some researchers based at institutions in developed countries may be tempted to 'export' their research activities to collaborating African institutions where ethical and legal frameworks on use of animals may be less stringent than in the developed countries. An appreciation of the intrinsic value of animals should be enough driving force for human beings to strive to promote humane treatment of animals. This paper gives an overview of uses and potential abuses of animals in research for the benefit of stakeholders such as researchers, research institutions, Ethics Review Committees (ERCs) and policy makers and ends with suggestions on possible ways of ensuring humane treatment of animals used in research in Africa in particular and globally in general.
- Published
- 2009
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4. Molecular Biogeography of Tribe Thermopsideae (Leguminosae): A Madrean-Tethyan Disjunction Pattern with an African Origin of Core Genistoides.
- Author
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Zhang, Ming-Li, Huang, Jian-Feng, Sanderson, Stewart C., Yan, Ping, Wu, Yu-Hu, and Pan, Bo-Rong
- Subjects
- *
DNA , *ANIMAL experimentation , *INSECTS , *MOLECULAR biology , *STATISTICS , *PHYSIOLOGY - Abstract
Thermopsideae has 45 species and exhibits a series of interesting biogeographical distribution patterns, such as Madrean-Tethyan disjunction and East Asia-North America disjunction, with a center of endemism in the Qinghai-Xizang Plateau (QTP) and Central Asia. Phylogenetic analysis in this paper employed maximum likelihood using ITS, rps16, psbA-trnH, and trnL-F sequence data; biogeographical approaches included BEAST molecular dating and Bayesian dispersal and vicariance analysis (S-DIVA). The results indicate that the core genistoides most likely originated in Africa during the Eocene to Oligocene, ca. 55-30 Ma, and dispersed eastward to Central Asia at ca. 33.47 Ma. The origin of Thermopsideae is inferred as Central Asian and dated to ca. 28.81 Ma. Ammopiptanthus is revealed to be a relic. Birth of the ancestor of Thermopsideae coincided with shrinkage of the Paratethys Sea at ca. 30 Ma in the Oligocene. The Himalayan motion of QTP uplift of ca. 20 Ma most likely drove the diversification between Central Asia and North America. Divergences in East Asia, Central Asia, the Mediterranean, and so forth, within Eurasia, except for Ammopiptanthus, are shown to be dispersals from the QTP. The onset of adaptive radiation at the center of the tribe, with diversification of most species in Thermopsis and Piptanthus at ca. 4-0.85 Ma in Tibet and adjacent regions, seems to have resulted from intense northern QTP uplift during the latter Miocene to Pleistocene. [ABSTRACT FROM AUTHOR]
- Published
- 2015
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5. Vitex doniana Leaves Extract Ameliorates Alterations Associated with 7, 12-Dimethyl Benz[a]Anthracene-Induced Mammary Damage in Female Wistar Rats.
- Author
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Forcados, Gilead Ebiegberi, Sallau, Abdullahi Balarabe, Muhammad, Aliyu, Erukainure, Ochuko Lucky, and James, Dorcas Bolanle
- Subjects
PHYTOTHERAPY ,ANIMAL experimentation ,HYDROCARBONS ,INFLAMMATION ,MOLECULAR structure ,RATS ,TAMOXIFEN ,TUMORS ,PLANT extracts - Abstract
Vitex doniana leaves are used traditionally in West Africa for the treatment of swellings and cancer. We investigated if Vitex doniana leaves extract could ameliorate 7, 12-dimethylbenz[a]anthracene (DMBA)-induced mammary damage. Female Wistar rats aged 52 ± 2 day were administered 80 mg/kg DMBA. After monitoring for 150 day, rats were administered 0, 50, 100, 200 mg/kg Vitex doniana and 20 mg/kg Tamoxifen for 14 day. Serum estrogen receptor-α, IL-1β and TNF -α levels were determined using ELISA kits. Oxidative stress markers in mammary tissue homogenates were determined using standard spectrophotometric methods. Histopathological examination was done using hematoxylin and eosin staining and cyclooxygenase-2 (COX-2) expression using immunohistochemistry. Liquid chromatography-mass spectrometry was used to determine components present in the extract. Although tumors were not observed, significantly (p < 0.05) lower estrogen receptor-α, malondialdehyde, IL-1β and TNF -α levels, significantly (p < 0.05) higher glutathione and catalase activity, attenuation of malignant epithelial hyperplasia and mild COX-2 expression were observed in rats administered Vitex doniana when compared to DMBA-induced untreated control. Liquid chromatography-mass spectrometry analysis of the V. doniana extract revealed the presence of 4,5-dihydroxy-7-methoxy-6-methylflavone and vanillylamine, which are compounds with reported antioxidant and anti-inflammatory effects. Collectively, treatment with Vitex doniana ameliorated some derangement observed in DMBA-induced rats. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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6. Effect of Aqueous Extract of Adansonia digitata Stem Bark on the Development of Hypertension in L-NAME-Induced Hypertensive Rat Model.
- Author
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Ntchapda, Fidèle, Bonabe, Christian, Atsamo, Albert Donatien, Kemeta Azambou, David Romain, Bekono Fouda, Yannick, Imar Djibrine, Soudy, Seke Etet, Paul F., and Théophile, Dimo
- Subjects
CARDIOVASCULAR disease prevention ,AMINOTRANSFERASES ,ANIMAL experimentation ,ANTIOXIDANTS ,AORTA ,BARK ,CELL physiology ,CHOLESTEROL ,CREATININE ,ELECTROCARDIOGRAPHY ,GLUTATHIONE ,DIET therapy for heart diseases ,HEMODYNAMICS ,HYPERTENSION ,ANTIHYPERTENSIVE agents ,LIPIDS ,LOW density lipoproteins ,NITRIC oxide ,RATS ,PLANT stems ,TRADITIONAL medicine ,TRIGLYCERIDES ,MALONDIALDEHYDE ,PLANT extracts ,OXIDATIVE stress ,DESCRIPTIVE statistics ,PHARMACODYNAMICS - Abstract
Background. Adansonia digitata is a plant used against cardiovascular disorders in African folk medicine. We assessed the effects of the aqueous extract of its stem bark on the development of hypertension in L-NAME-induced hypertensive rats. Methods. The animals were administered L-NAME once daily for 3 weeks (25 mg/kg, i.p.), concomitantly with aqueous extract of A. digitata stem bark (100 and 200 mg/kg, p.o.) or captopril (20 mg/kg, p.o.). Then, hemodynamic and electrocardiographic parameters, oxidative stress markers, and the lipid profile were assessed in the blood and heart, aorta, and kidney homogenates, and histopathological analyses were performed. Results. L-NAME-induced hypertensive control animals, but not the animals concomitantly treated with A. digitata extract, displayed increases in the mean arterial blood pressure (21.64% difference, p < 0.001 , vs. dose 200 mg/kg), systolic arterial blood pressure (21.33%, p < 0.001), and the diastolic arterial blood pressure (21.84%, p < 0.001). In addition, hypertensive control animals displayed (i) increases in serum triglycerides, total cholesterol, LDL, and creatinine levels, malondialdehyde and transaminase activities, and atherogenic index; (ii) decreases in serum HDL, catalase, reduced glutathione, and nitric oxide; and (iii) aorta wall thickening, inflammatory cell infiltration, and cell loss in the cardiac muscle and renal tissues. As captopril, the extract prevented hypertension-like changes in lipid profile, cardiac, hepatic, and renal affection indicators, and oxidative stress markers. Conclusion. Our findings suggest that the extract of A. digitata has antihypertensive and antioxidant effects in L-NAME-induced hypertension rat models. These effects partly justify the traditional medicine use against cardiovascular disorders. [ABSTRACT FROM AUTHOR]
- Published
- 2020
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7. Do vegetarians less frequently carry ESBL/pAmpC-producing Escherichia coli/Klebsiella pneumoniae compared with non-vegetarians?
- Author
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Meijs, Anouk P, Gijsbers, Esther F, Hengeveld, Paul D, Veenman, Christiaan, Roon, Annika M van, Hoek, Angela H A M van, Greeff, Sabine C de, Duijkeren, Engeline van, Dierikx, Cindy M, van Roon, Annika M, van Hoek, Angela H A M, de Greeff, Sabine C, and van Duijkeren, Engeline
- Subjects
VEGETARIAN foods ,KLEBSIELLA pneumoniae ,ESCHERICHIA coli ,ENTEROBACTERIACEAE ,VEGETARIANS ,HAND washing ,MEAT ,KLEBSIELLA ,BACTERIAL proteins ,RESEARCH ,SEQUENCE analysis ,ANIMAL experimentation ,RESEARCH methodology ,MEDICAL cooperation ,EVALUATION research ,HYDROLASES ,COMPARATIVE studies ,ESCHERICHIA coli diseases ,GENES ,ANTIBIOTICS - Abstract
Background: ESBL and plasmid-mediated AmpC (pAmpC)-producing Enterobacteriaceae are frequently found on meat products in Dutch retail, especially on poultry.Objectives: We investigated whether vegetarians are at lower risk of carrying ESBL/pAmpC-producing Escherichia coli/Klebsiella pneumoniae (ESBL-E/K) compared with persons who consume meat.Methods: Vegetarians, pescatarians (vegetarians who eat fish) and non-vegetarians (persons who eat meat at least three times per week) were asked to send in a faecal sample and a questionnaire. ESBL-E/K were cultured and MLSTs were determined. ESBL/pAmpC genes were analysed using PCR and sequencing. The risk of ESBL-E/K carriage in the three study groups was analysed using multivariable logistic regression.Results: Prevalence of ESBL-E/K carriage was 8.0% in vegetarians (63/785; 95% CI 6.3-10.1), 6.9% in pescatarians (27/392; 95% CI 4.8-9.8) and 3.8% in non-vegetarians (14/365; 95% CI 2.3-6.3). Multivariable analysis showed an OR for ESBL-E/K carriage of 2.2 for vegetarians (95% CI 1.2-4.0) and 1.6 for pescatarians (95% CI 0.8-3.2) compared with non-vegetarians. The predominant MLST was E. coli ST131 and the most common ESBL genes were blaCTX-M-15, blaCTX-M-27, blaCTX-M-14 and blaCTX-M-1 in all diet groups. Independent risk factors for ESBL-E/K carriage were travel to Africa/Latin America/Asia (OR 4.6; 95% CI 2.8-7.7) in the past 6 months and rarely/never washing hands before food preparation (OR 2.5; 95% CI 1.2-5.0).Conclusions: Vegetarians and pescatarians did not have a lower risk of ESBL-E/K carriage compared with non-vegetarians, indicating that eating meat is not an important risk factor for ESBL-E/K carriage. [ABSTRACT FROM AUTHOR]- Published
- 2020
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8. Active chemical fractions of stem bark extract of Khaya grandifoliola C.DC and Entada africana Guill. et Perr. synergistically protect primary rat hepatocytes against paracetamol-induced damage.
- Author
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Njayou, Frédéric Nico, Fondjo Kouam, Arnaud, Nemg Simo, Brice Fredy, Nkouatchoua Tchana, Angèle, and Fewou Moundipa, Paul
- Subjects
CIRRHOSIS of the liver ,LIVER diseases ,PHYTOTHERAPY ,HEPATOTOXICOLOGY -- Risk factors ,ACETAMINOPHEN ,ALTERNATIVE medicine ,ANIMAL experimentation ,BIOLOGICAL assay ,CELL culture ,PROTEINS ,RATS ,RESEARCH funding ,DATA analysis ,DISEASE risk factors - Abstract
Background: Khaya grandifoliola (Meliaceae) and Entada africana (Fabaceae) are traditionally used in Bamun (a western tribe of Cameroon) traditional medicine for the treatment of liver related diseases. In this study, the synergistic hepatoprotective effect of respective active fractions of the plants were investigated against paracetamol-induced toxicity in primary cultures of rat hepatocytes. Methods: Paracetamol conferred hepatocyte toxicity, as determined by the 3-(4,5-dimethylthiazol-2-yl) -2,5-diphenyltetrazolium (MTT) assay, alanine aminotransferase (ALT), superoxide dismutase (SOD), catalase (CAT) activities, malondialdehyde (MDA) and glutathione (GSH) content assays. The crude extracts were fractionated by flash chromatography and fractions were tested for hepato-(protective and curative) activities. The most active fractions of both plants were tested individually, and in combination based on their respective half effective concentration (EC50). Results: The methylene chloride/methanol fractions of K. grandifoliola (75:25 v/v) (KgF25) and E. africana (90:10 v/v) (EaF10) were found to be the most hepato-protective with EC50 values of 10.30 ± 1.66 µg/ml and 13.47 ± 2.06 µg/ml respectively, comparable with that of silymarin (13.71 ± 3.87 µg/ml). These fractions and their combination significantly (P <0.05) improved cell viability, inhibited ALT leakage and MDA formation, and restored cellular CAT, SOD activities and GSH content. The combination was more effective in restoring biochemical parameters with coefficients of drugs interaction (CDI) less than 1. Conclusion: These findings demonstrate that the active fractions have synergistic action in the protection of rat hepatocytes against paracetamol-induced damage and suggest that their hepatoprotective properties may be maximized by using them in combination. [ABSTRACT FROM AUTHOR]
- Published
- 2016
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9. Antisickling and toxicological evaluation of the leaves of Scoparia dulcis Linn (Scrophulariaceae).
- Author
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Abere, Tavs A., Okoye, Chiagozie J., Agoreyo, Freddy O., Eze, Gerald I., Jesuorobo, Rose I., Egharevba, Clement O., and Aimator, Pauline O.
- Subjects
FOLIAR diagnosis ,HEMOGLOBINOPATHY ,MEDICINAL plants ,ANIMAL experimentation ,ANTISICKLING agents ,MICE ,RATS ,TOXICOLOGY ,PHYTOCHEMICALS ,DESCRIPTIVE statistics ,ONE-way analysis of variance ,PREVENTION - Abstract
Background: Scoparia dulcis Linn (Scrophulariaceae) together with other medicinal plants serve as antisickling remedies in Africa. This study was aimed at investigating the antisickling activity of the leaves of the plant as well as establishing the toxicological profile. Method: Chemical tests were employed in phytochemical investigations. Evaluation of the antisickling activity involved the inhibition of sodium metabisulphite-induced sickling of the HbSS red blood cells obtained from confirmed sickle cell patients who were not in crises. Concentrations of the crude extract and its fractions were tested with normal saline and p-hydroxybenzoic acid serving as controls. Acute toxicological evaluation was carried out in mice while 30-day assessment was done in rats. Results: Phytochemical screening revealed the presence of alkaloids, tannins, flavonoids and saponins. Percentage sickling inhibitions of the aqueous methanol extracts of S. dulcis were significant all through the period of assay p < 0. 05 compared to normal saline, but not significant with PHBA. The fractions had less activity compared to the crude extracts. The LD 50 of the extract in mice was above 8000 mg/kg body weight when administered orally. Toxicological evaluations at 250 and 500 mg/kg showed mild congestion in virtually all the target organs. Conclusion: The antisickling results confirmed traditional usage of Scoparia dulcis in the management of Sickle cell disorders and a candidate for further investigations. [ABSTRACT FROM AUTHOR]
- Published
- 2015
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10. Emilia coccinae (SIMS) G Extract improves memory impairment, cholinergic dysfunction, and oxidative stress damage in scopolamine-treated rats.
- Author
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Foyet, Harquin Simplice, Ngatanko Abaïssou, Hervé Hervé, Wado, Eglantine, Acha, Emmanuel Asongalem, and Alin, Ciobica
- Subjects
MEMORY disorders ,ALZHEIMER'S disease ,ANIMAL experimentation ,BIOCHEMISTRY ,CONFIDENCE intervals ,ENZYMES ,GLUTATHIONE ,PARASYMPATHOMIMETIC agents ,RATS ,RESEARCH funding ,SCOPOLAMINE ,MALONDIALDEHYDE ,PLANT extracts ,RANDOMIZED controlled trials ,DATA analysis software ,DESCRIPTIVE statistics ,ODDS ratio ,ONE-way analysis of variance ,THERAPEUTICS - Abstract
Background: E. coccinae (SIMS) G. (Asteraceae) is an annual plant commonly found throughout the plain of the Central Africa and widely used in Cameroonian folk medicine for the treatment of fever and convulsions in children. We previously reported that the methanolic extract of this plant improved spatial memory. However no underlying mechanism was explored. The present study was undertaken to investigate the effects of the hydroalcoholic extract of Emilia coccinae on memory in scopolamine treated rats and to propose possible mechanisms of action. Methods: Novel object recognition and Y-maze paradigm were used to test memory while oxidative profile, AChE and ACh level of the whole brain were assessed to outline the mechanism of nootropic activity of the extract. 200 and 400 mg/kg of the extract were chronically administrated during 14 consecutive days in separate groups of scopolamine intraperitoneal treated rats (1.5 mg/kg). Results: The hydroalcoholic extract of Emilia coccinae (HEEC) at the dose of 200 mg/kg significantly improved the memory of rats and reversed the amnesia induced by scopolamine. In addition, we showed that this extract is decreasing the acetyl cholinesterase activity while also increasing the acetylcholine levels in the brain. HEEC (200 and 400 mg/kg) significantly increased antioxidant enzyme activities (SOD, GSH and CAT) and reduced lipid peroxidation (MDA level) in the rat whole brain homogenates. Conclusions: Taken together, our results suggested that the hydroalcoholic extract of Emilia coccinae ameliorated the cognitive dysfunction in scopolamine treated rats through the blockage of the oxidative effect of scopolamine and inhibition of AChE activity. [ABSTRACT FROM AUTHOR]
- Published
- 2015
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11. Research approaches for improved pro-poor control of zoonoses.
- Author
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Schelling, Esther, Grace, Delia, Willingham III, A. Lee, Randolph, Tom, and Willingham, A Lee 3rd
- Subjects
ZOONOSES ,PREVENTION of communicable diseases ,DISEASE vectors ,LIVESTOCK ,PUBLIC health ,POOR people ,INFECTIOUS disease transmission ,FOOD supply ,ANIMAL experimentation ,COMMUNICABLE diseases ,COMPARATIVE studies ,DEVELOPING countries ,RESEARCH methodology ,MEDICAL cooperation ,POVERTY ,RESEARCH ,EVALUATION research ,STANDARDS - Abstract
Background: Developing countries face difficulties in sustainably utilizing tools to effectively implement control measures for zoonoses. This is mainly due to dispersed and heterogeneous smallholder livestock systems, predominance of informal markets, poor infrastructure and lack of resources to deliver information, interventions, and regulations. In addition, developing countries lack an evidence base for planning and targeting control efforts. Zoonotic infections are receiving more and more international attention as diseases of neglected and impoverished communities, at the intersection between livestock production, human health, and poverty.Objective: To review research innovations and trends that can help identify and test targeted control strategies for zoonoses tailored to poor communities, focusing particularly on Africa.Methods: Review of recommendations of relevant working groups and scientific literature.Results: New and innovative research approaches promise to better capture the impact of zoonoses from a societal perspective and the perspective of poor livestock owners through more comprehensive frameworks that consider benefits of the control of zoonoses to the public health, livestock, and private sectors. It is challenging to better assure food safety in informal markets. Risk-based approaches with participatory elements provide a framework in which stakeholders can decide an appropriate level of protection to balance the needs for safe food, cheap food, and pro-poor economic growth. Appropriate information for all stakeholders and capacity-building of national and regional authorities is an important element of this process. New diagnostic tools that are accurate and easily used in developing-country health centers and markets can assist in reporting of cases, detection of patients, and testing of control strategies.Conclusions: A research agenda on zoonoses of the livestock sector should be interdisciplinary and participatory and include intersectoral collaborations, notably between the livestock and public health sectors. [ABSTRACT FROM AUTHOR]- Published
- 2007
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