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Conservation status and growth response of cnidoscolus aconitifolius (mill.) johnst. to fertilizer in Ibadan, South-western Nigeria
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Phenology and rate of sprouting of launaea taraxacifolia (willd.) amin ex c. jeffrey in Ibadan, Oyo state, Nigeria
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EFFECTS OF SIMULATED LABORATORY AND ENRICHED LABORATORY GUIDE MATERIAL EXPERIMENTS ON STUDENTS’ LEARNING OUTCOMES IN BASIC SCIENCE IN OYO STATE, NIGERIA
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- A nationwide equine influenza virus surveillance was carried out between January 1989 and January 1995 during which nasopharyngeal swabs, tracheal washes and respiratory tract tissue homogenates were obtained from symptomatic and asymptomatic equine species in various parts of Nigeria for virus isolation and characterisation. Three equine influenza viruses were independently isolated in 10-11 day old embryonated hen eggs and Madin Darby canine kidney monolayer cells with TPCK-trypsin incorporated into the culture medium. The virus isolates were characterized antigenically, immunogenically and genetically which made them the first equine influenza viruses isolated and characterized in tropical Africa. Antigenic analyses with mono-specific antisera raised against a number of respiratory disease viruses including Paramyxoviruses, Adenoviruses, Herpes viruses, Alphavirus, Rhinoviruses, Equine arteritis viruses, African horse sickness viruses and Influenza viruses showed that the three virus isolates were influenza A viruses while haemagglutination and neuraminidase inhibition assays using influenza virus specific Mabs and polyclonal antisera showed the three viruses to be antigenically H3N8, members of equine-2 subtype of influenza A viruses. The three isolates were respectively named A/Equine/Ibadan/4/91, A/Equine/Ibadan/6/91 and A/Equine/Ibadan/9/91 in accordance with the recommendations of the World Health Organisation and the International Committee on Virus Taxonomy. Their antigenic cross-reactivity with panels of Mabs and polyclonal antisera indicated that the three viruses were antigenically divergent although they were all H3N8 viruses and were representatives of a homogenous population. They were reactive with Mabs and antisera directed against H3 equine viruses isolated in 1963, 1976, 1979, 1981 and 1986. This broad reactivity suggested that these isolates were similar to but not still different from those isolated in Europe and USA between 1963 and 1987. Virus protein synthesis and cleavability of the HA polypeptide in tissue culture were investigated by pulse-chase experiments. The results showed some heterogeneity in the non-glycosylated polypeptides particularly those of the ribonucleoprotein (RNP) complex while the HA glycoproteins of the three viruses were not cleaved in any of the cell types used in contrast to equine H7 and pathogenic avian H5 and H7 HAs. The molecular weights of the polypeptides were within the range previously determined for influenza A viruses. The heterogeneity of the RNP complex and antigenic divergence of the viruses’ HAs were confirmed by sequence analysis carried out in molecular studies. Virus infectivity was investigated by plaque assay using chicken embryo fibroblast (CEF) monolayer cells and virus titration in embryonated hen eggs. The results showed that the viruses were infectious with plaguing efficiency being comparable to efficiency of virus infectivity in embryonated hen eggs. Infectivity, antigenicity and immunogenicity of the three viruses were confirmed in-vitro using peripheral blood lymphocytes in lymphoproliferation assays and in-vivo in an equine model in which the viruses induced haemagglutination inhibiting and protective neutralising antibodies following experimental infections. The proliferating cells were also characterised and the immunoglobulin isotypes produced were determined. Molecular characterisation and genetic analyses of the three viruses were accomplished to determine the origin of the genes encoding the virus non-glycosylated polypeptides as well as those of the surface HA glycoprotein. Reverse transcription (RT) results showed the eight RNA segments of the three isolates and confirmed them as influenza A virus RNAs. No subgenomic RNAs or defective interfering particles were observed in the RNA transcripts. Nucleotide sequence analyses were carried out using three sequencing strategies of cDNA, vRNA and plasmid DNA sequencing with the dideoxy chain termination procedure. Partial nucleotide sequences were obtained from cDNAs, vRNAs and plasmid DNA clones of RNA segments 1, 2, 3, 5, 7 and 8 with the method of multiplex RT/PCR and cycle sequencing using radiolabelled segment specific oigonucleotides of 18, 24 or 25 mers. Complete nucleotide sequences of segment 4 (HA genes) were also determined on the same PCR products (cDNA) and vRNA using end-labelled oligonucleotides of both plus and minus sense. The partial nucleotide sequence data were analysed using a programme for "best-local-homology- rapid-search" on a digital array processor while the complete HA nucleotide and deduced amino acid sequence analyses were carried out using the University of Wisconsin Genetics Computer Group (GCG) package of programmes. Phytogenetic analysis was done with the distances, neighbour joining and DNAPARS of the PHYLIP package. Analyses of the viruses’ gene sequences confirmed that their genomes were similar to each other and to those of other H3N8 influenza viruses isolated from equines and also revealed the origin, evolution and genetic relatedness of the genes. Comparison of the partial cDNA sequences with virus DNA sequences in the database (EMBL sequence library) showed that for segments 1, 2, 5, and 7, the closest related sequences were from equine H3 viruses isolated in 1986 in USA (Tennesse/5/86 for segments 2, 5 and 7, Kentucky/2/86 for segments 1 and 5. Segment 5 was equally related to both viruses). The nucleotide sequence for segment 3 was most closely related to an equine-1 virus isolated in U.K. in 1973 (London/1416/73, H7N7) probably due to genetic exchange while segment 8 sequence was most closely related to an equine H3N8 virus isolated in U.K. in 1976 (Newmarket/76). The complete nucleotide and deduced amino acid sequences as well as phytogenetic analysis of the HA genes (RNA segment 4) showed a closer relationship albeit with nucleotide and amino acid substitutions between the three Ibadan viruses and those that were isolated in Europe in 1989 and 1991, the prototypic European strain, Suffolk/89 and Arundel/12369/91 isolated in U.K., Taby/91 isolated in Sweden, Hong Kong/92 isolated in the Far East in 1992 and Laplata/1/93 isolated in South America. These findings group the Ibadan viruses with those predominating and contemporarily causing disease in the Western Hemisphere rather than with viruses previously isolated from the north and south of African continent. Variation was observed in the nucleotide sequences of the Ibadan viruses HA genes. Some of the base changes resulted in amino acid changes which mapped to antigenic sites or within signal sequence in the HA1 domain as a result of a process of antigenic or genetic drift. The Ibadan viruses also showed some variation from the prototypic European virus (Suffolk/89) and these base changes also resulted in amino acid changes resulting in antigenic drift. Phytogenetic analysis showed the evolutionary lineages in equine H3 viruses isolated since 1963 along two paths one of which included the Ibadan viruses as well as viruses isolated in Europe between 1989 and 1991 and the Far East in 1992 and S. America in 1993 which form the 1989/93 cluster while the other lineage included viruses isolated in South America in 1987 and 1988 (Brazil/87, Laplata/88) and in the Far East in 1971 (Tokyo/3/71) all of which are very close to the original prototype equine-2 virus (Miami/63). These results demonstrate a faster evolutionary rate for recent equine H3 HA genes away from the original prototype virus. Overall, the results of these studies have (i) confirmed the occurrence of equine-2 H3N8 influenza viruses of distinct lineages in Nigerian equine populations in a tropical environment (ii) indicated antigenic drift among equine H3N8 viruses as earlier reported and confirmed that drift strains can co-circulate in equine populations, (iii) showed the origin, evolution and genetic relatedness of the viruses genes as well as their biological characteristics, (iv) provided the hitherto unavailable information on the status of equine influenza virus in this part of the world and (v) served to re-emphasise the potential of influenza virus for rapid global spread and the need for better control strategies. 1 results 1
- ABSTRACT Mosquitoes are vectors of various diseases of public health importance and their control has been premised on the use of synthetic insecticides. However, these insecticides are laden with problems of high cost, environmental hazards and development of resistance in many species of mosquitoes. Alternatives to synthetic substances are the natural products. Plant species, Clerodendrum inerme, have been found to inhibit the growth of Aedes aegypti and Culex quinquefasciatus larvae. However, there is paucity of information on the anti-mosquito properties of the Nigerian species, C. polycephalum Baker. Therefore, the aim of the study was to investigate the anti-mosquito properties of the methanol extract of the leaves of C. polycephalum. Fresh leaves (1.4 kg) of C. polycephalum were harvested and brought to the laboratory. The leaves were air-dried, powdered, extracted with methanol and concentrated to dryness using rotary evaporator. The crude methanol extract was subjected to phytochemical analysis according to standard method and separated into n-hexane, dichloromethane, ethyl acetate and ethanol fractions using vacuum liquid chromatography. The most active fraction (ethanol), was subjected to column chromatography. Gas Chromatography - Mass Spectroscopy (GC-MS) was used to analyse the subfraction which was ultra-violet active. The crude methanol extract and fractions (250–8000 ppm) were tested for larvicidal activity. The methanol extract was further tested for anti-oviposition, effects on growth and development on Aedes aegypti, Anopheles gambiae and Culex quinquefasciatus mosquitoes together with corresponding positive (lambda-cyhalothrin) and negative controls (dimethylsulfoxide) using World Health Organisation procedures. Toxic effects, determined by mortality, on representative non-target organisms was evaluated on adult Biomphalaria glabrata (snail) and tadpoles of Bufo regularis. Ten each of the organisms were used per concentration. Data were analysed using descriptive statistics and student’s t-test at α0.05. Tannins, flavonoids, saponins and alkaloids were identified from the crude extract. Seventeen compounds were detected from ethanol subfraction, with quantities varying from 0.0 to 23.7%. Prominent compounds include 4-((1E)-3-Hydroxy-1-propenyl)-2-methoxyphenol (7.5%), 2-Hydroxy-5-methylbenzaldehyde (6.1%) and Ethyl iso-allocholate (23.7%). Larvicidal activities of crude methanol extract and fractions were in the order ethanol (100.0%) > methanol (96.6%) > n-hexane (7.5%) > DCM/ethyl-acetate (0.0%) at 2000ppm after 24h. Susceptibilities of mosquito larvae to methanol extract were also in the order A. aegypti > A. gambiae > C. quinquefasciatus. Mortality of the larvae was significantly different from the positive control. Anti-oviposition index increased (46.4-89.9) with extract concentrations. Morphological deformities of larvae and pupae were observed at the higher doses of 2000 ppm (A. aegypti), 5000 ppm (A. gambiae) and 7000 ppm (C. quinquefasciatus). Mosquito adult emergence inhibitions (24.0-100.0%) were recorded at 1100–5600 ppm concentration levels. The crude extract had no effect on the tadpoles at 250–1000 ppm, but the mortality of the snail at 250–2000ppm, varied from 10.0–95.0%. Clerodendrum polycephalum leaves contained biological components capable of inhibiting the survival and development of mosquitoes and could be exploited in the control of mosquitoes. 1 results 1
- Academic achievement 1 results 1
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- Allelochemicals are being explored as environmentally friendly options in weed management and crop yield improvement as opposed to use of synthetic pesticides which have serious environmental damages. Allelopathic effects of aqueous extracts of different parts of Olax subscorpioidea on Okra seed germination in Petri-dish bioassays and okra performance in pot experiment were conducted in the Department of Crop Protection and Environmental Biology, University of Ibadan using a complete randomized design (CRD) and with treatments replicated five times. Ten okra seeds in three replicates were treated in separate petri-dishes with 2 ml water extracts of stem, leaf, fruit, bark and root of Olax subscorpioidea, and 2 ml distilled water (control) in two trials. Pot trials was carried out using okra seedlings with treated with 100 ml extracts at seven days intervals. Data were collected on number of germinated seeds daily and lengths of five randomly selected plumules and radicles at 7 days after sowing (DAS). Number of leaves, plant height, root and shoot dry weight of seedlings were also measured using standard methods. Data were analyzed by analysis of variance. Statistically significant (P<0.05) means were separated using Duncan’s Multiple Range Test. Leaf extract had the highest concentrations of phenolic, flavonoid and saponin compounds compared, while the stem extract had the least metabolite concentrations. Leaf extracts exerted highest inhibition on okra germination at 2 and 7 DAS in the first trial and at 7 DAS in the second trial compared to the bark, stem, root and fruit extracts of Olax subscorpioidea. The seedling growth and yield parameters in treatment extracts were better than control. In conclusion, Olax subscorpioidea has allelopathic potential with effects on germination and seedling growth of okra. It can be used as an alternative bioherbicide. Its production and agricultural potentials should be promoted. 1 results 1
- Allelopathy 1 results 1
- Anambra state 1 results 1
- Animal wastes, 1 results 1
- Animation and video-based flipped classroom strategies 1 results 1
- Antimicrobial activity 1 results 1
- Attitude to biology 1 results 1
- Background: Breastfeeding is known to be the biological norm. Despite this, many women wean their babies because of perceived insufficient breast milk production. Mothers are sometimes advised to increase their fluid intake in the hope that this could improve breast milk production. The effect of extra fluid on human breast milk production is not well established, however. Objectives: To assess the effect of extra fluid for breastfeeding mothers on milk production/supply and infant growth. Search methods We searched the Cochrane Pregnancy and Childbirth Group’s Trials Register (27 April 2014), MEDLINE (1966 to 27 April 2014), African Journals Online (27 April 2014) and reference lists of retrieved studies. Selection criteria: Randomised controlled trials and quasi-randomised controlled trials on extra fluids for breastfeeding mothers. Data collection and analysis Two review authors independently assessed the potential studies for inclusion and assessed trial quality. Main results: Five trial reports were retrieved using the search strategies. Four trials were excluded. We did not identify any randomised controlled trials for inclusion but we included one quasi-randomised study (involving 210 women) that evaluated the effect of extra fluid for breastfeeding mothers on breastfeeding outcomes. The study was considered to be at a high risk of bias. Only one of this review’s primary outcomes was reported (breast milk production (as defined by the trialist)) but data were not in a suitable format for analysis (no standard deviations or standard errors were reported). The trialist reported that advising women to drink extra fluids did not improve breast milk production. No data were reported for the review’s other primary outcomes: satisfactory weight gain in the infant (as defined by the trialists) and duration of exclusive breastfeeding (months). Similarly, no data were reported for any of this review’s secondary outcomes: duration of any breastfeeding; mother’s satisfaction with breastfeeding; hydration in mother; dehydration in the infant; or episodes of gastrointestinal illness. 1 results 1
- Background: Despite the availability of a safe and effective vaccine for over 50 years, measles remains a leading cause of death among young children in developing countries. Aim: This study assessed the knowledge and home treatment of measles by caregivers of children under 5 years. Setting: Abebi community, Ibadan, Oyo State, Nigeria. Methods: A descriptive cross-sectional study of 509 caregivers of children aged 6 months to 5 years in a semi-urban community in Ibadan was conducted using a multi-stage sampling method. An interviewer administered structured questionnaire was used to collect information on socio-demographic characteristics, knowledge of aetiology, main symptoms and signs, and home treatment of measles. Chi-square test and logistic regression were used to explore associations at 5% level of significance. Results: Most of the caregivers were females (96.3%), married (86.1%) and were the biological parents of the children (90.9%). More than half had good knowledge of the cause (59.7%) and main symptoms and signs (52.8%) of measles. However, the composite knowledge was good in 57.6% of caregivers. Over half (54.4%) of the caregivers reported that their children ever had measles. Majority (91.3%) of caregivers whose children had measles gave home treatment, while 24 (8.7%) sought treatment from health facilities alone. There was a significant association between caregivers’ educational status, age, tribe and marital status and their knowledge of measles; however, tribe was the only significant predictor of knowledge after regression analysis. Caregivers from other tribes were 3.3 times more likely to have good knowledge of measles than Yoruba caregivers. Caregivers who were 35 years and older compared to those younger than 35 years (OR: 0.625; 95% CI: 0.425–0.921) and those who were not currently married compared to those married (OR: 0.455; 95% CI: 0.273–0.758) had lower odds of having good knowledge of measles, respectively. Conclusion: Home treatment by caregivers of children with measles is high. Health education on the cause, prevention and treatment of measles should be provided for caregivers. 1 results 1
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- Journal of Genetics 6 results 6
- Reproductive Medicine and Biology 6 results 6
- GigaScience 5 results 5
- Biodiversity Data Journal 4 results 4
- Biometrical Letters 4 results 4
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- Clinical Proteomics 3 results 3
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- Proceedings of the Vertebrate Pest Conference 3 results 3
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