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The role of the beta3-adrenergic receptor (β3-AR) in cardioprotection by Alsalhin, Aisha Khlani Hassan
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Page will reload when a filter is selected or excluded.- A combination of physiological, biochemical and molecular characteristics was used in the study of 291 strains of staphylococci isolated from man, goats, sheep, poultry and other animals. Novobiocin-resistant strains were more prevalent amongst the coagulase-negative staphylococci examined. Of the 110 caprine strains of coagulase-negative staphylococci, 91 (87.7 per cent) were novobiocin-resistant. The strains identified to species level were found to be Staphylococcus sciuri, Staphylococcus lentus, Staphylococcus xylosus, Staphylococcus gallinarum, Staphylococcus cohnii and Staphylococcus saprophyticus. Staphylococcus sciuri and Staphylococcus lentus were easily differentiated from other novobiocin-resistant staphylococci by a positive-oxidase reaction. Morphologically, Staphylococcus sciuri and Staphylococcus lentus appeared indistinguishable. Staphylococcus lentus appeared more biochemically active than Staphylococcus sciuri and indeed other coagulase-negative staphylococci isolated from goats with the exception of Staphylococcus gallinarum. Differentiation of Staphylococcus sciuri from Staphylo coccus lentus was facilitated by the inability of several strains of Staphylococcus sciuri to produce acid from melibiose. Novobiocin-resistant staphylococcal species were the only ones isolated from sheep and they had almost identical physiological and biochemical characteristics with those of caprine origin. Staphylococcus gallinarum, a new species of coagulase-negative staphylococci isolated from animals was found amongst the present collection of coagulase-negative staphylococci. Staphylococcus gallinarum resembled Staphylococcus lentus in its acid production from several carbohydrates used but its oxidase-negative reaction was used in its differentiation from Staphylococcus lentus. Staphylococcus gallinarum strains commonly produced acid from fructose, maltose, D-(+)-mannose, D-(-)-ribose, sucrose and D-(+)-trehalose. Most of the novobiocin- resistant, coagulase-negative staphylococci from animals were physiologically active as they produced a variety of extracellular products. Weak desoxyribonuclease activities were commonly found amongst Staphylococcus sciuri and Staphylococcus lentus and the strong reaction produced by Staphylococcus hyicus was found to be of diagnostic use. One strain of Staphylococcus sciuri produced thermostable nuclease and another strain of Staphylococcus lentus produced staphylokinase. Whilst intense protease production was commonly associated with Staphylococcus sciuri and Staphylococcus lentus, none of these strains produced lipolytic effects on egg-yolk medium whilst lipolytic effects were seen in strains of Staphylococcus xylosus and Staphylococcus cohnii. The characteristics of the novobiocin-resistant, coagulase-negative staphylococci isolated from humans did not differ from those of animal strains. The strains of Staphylococcus aureus isolated from humans and animals had similar physiological and biochemical characteristics. The production of hyaluroni-dase and acetoin from glucose was helpful in differentiating Staphylococcus aureus from other coagulase-positive Staphylococcus intermedius and Staphylococcus hyicus strains isolated from various hosts. The strains of Staphylococcus intermedius isolated from a man having a pet dog had similar characteristics as the other strains of Staphylococcus intermedius of canine origin. The human strain of Staphylococcus intermedius produced proteinase, phosphatase, desoxyribonuclease and thermostable nuclease but it failed to hydrolyze Tween 80 and did not produce hyaluronidase and acetoin from glucose. Acid production from a variety of carbohydrates by the human strain of Staphylococcus intermedius was however similar to that of Staphylococcus aureus of human origin but the strain did not produce acid from D-(+)-turanose. In the course of phage typing Staphylococcus aureus strains, a caprine phage was isolated from one strain (UI 150). Three caprine strains of Staphylococcus aureus that were untypable by using the International sets of phages for typing human strains of Staphylococcus aureus were susceptible to this caprine phage Gl. Staphylococcus aureus strains isolated from humans and goats which were susceptible to the phage 80/81 complex had similar antibiograms. Whilst several of the human strains of Staphylococcus aureus were found to be of human biotype, the caprine strains of Staphylococcus aureus belonged to biotype C. Resistance to tetracycline was found in some strains of Staphylococcus aureus of caprine origin whilst a higher percentage of human strains of Staphylococcus aureus produced penicillinase. Sensitivity to the cephalosporins was commonly found amongst all the Staphylococcus aureus strains examined. With human factor sera, all the Staphylococcus aureus strains isolated from humans were serotypable. Of the 14 caprine strains of Staphylococcus aureus examined, 10 were serotypable. Agglutinogens a5, b1, o and h2 were found amongst the Staphylococcus aureus strains of human and animal origins. Two Staphylococcus intermedius strains isolated from humans and dogs were serotypable and they had agglutinogen in common. All the 3 Staphylococcus aureus strains isolated from giant rats (Cricetomys gambianus) were serotypable with a5 and p agglutinogens being common to them. Some isolates were obtained which could not be identified the application of chemotaxonomic and molecular characterization procedures however provided a relationship to some of the newly-described species of staphylococci. Some relatively uncommon teichoic acids were found amongst some strains. A caprine strain of coagulase-positive, staphylococcus had glycerol and glucosamine teichoic acids whilst a strain of coagulase- negative staphylococcus of caprine origin possessed glycerol, glucose, galactose and N-acetylglucosamine teichoic acids. The guanine plus cytosine (G + C) content of the deoxyribonucleic acid (DNA) of some of the strains tested ranged between 32.7 and 34.6 per cent. DNA-DNA hybridization values amongst some of the coagulase- negative staphylococci revealed some relationships to Staphylococcus gallinarum, Staphylococcus lentus and Staphylococcus sciuri. 1 results 1
- Abelmoschus Esculentus 1 results 1
- Abiotic stress such as heavy metal contamination of agricultural soil limits crop production by disrupting plant’s physiological activities and seed germination. Exogenous proline, hormone and compost have been used to induce growth and stress tolerance in crop but little is known about their interactive and anti-oxidative roles in crop exposed to heavy metal stress. This study assessed the effects of pre-sowing seed soaking with exogenous proline (P) and hormones (Gibberellic acid; GA and Indole-acetic acid; IAA) on the Pb accumulation, osmolytes (P, phenolics; PH and Glycine betaine; GB), Photosynthetic pigments (chlorophyll and carotenoids) and stress indexes (H2O2 and malonialdehyde; MDA) of maize grown on compost amended Pb (23,959 mg kg-1 Pb) contaminated soil. Compost was applied at 20 t ha-1 and 40 t ha-1, P, GA and IAA were applied at 10 mM and 5 mM solely and in combinations to give a total of 34 treatments including control (Distilled water only) and replicated 3 times. Except in IAA treatment, seed pre-treatments with exogenous P and GA and soil amendment with compost generally enhanced chlorophyll production in maize and reduced GB, carotenoids, H2O2 and MDA in treated seeds compared to control. With regards to stress indexes G2+C1 gave the lowest values. Sole application of P1, P2, C2, G1 and I2 enhanced the production of proline in treated plants compared to combined application. Combination with compost was better than hormonal combination. A combination of P2 with C (40 t ha-1) (P2C2) gave the maximum chlorophyll content and reduced the endogenous GB and P. Treatment with P2C2 also reduced Pb accumulation in plant. In conclusion, exogenous application of hormones and proline in combination with organic amendment induces heavy metal tolerance in maize and increased protection against oxidative stress compared to contaminated control. The technique that can enhance crop growth on contaminated soil, reduce metal uptake and provide osmo-protection could be a promising approach. 1 results 1
- Antioxidants 1 results 1
- Background. Irvingia gabonensis kernel polymer has gained attention indrug delivery systems because ofits compatibility and degradation under natural and physiological conditions. Objectives. This study aimed toevaluate Irvingia gabonensis polymer asamatrix system for thecontrolled delivery of ibuprofen incomparison toxanthan gum and hydroxypropylmethylcellulose (HPMC). Materials and methods. Irvingia gabonensis polymer was extracted using established methods and dried using theoven- and freeze-drying methods. Ibuprofen tablets were prepared bydirect compression and theeffects ofpolymer concentration (10–50%), excipients (lactose, microcrystalline cellulose and dicalcium phosphate dihydrate) and polymers (xanthan gum and HPMC) onthemechanical and drug release proper¬ties ofthetablets were evaluated. Density measurements and theHeckel and Kawakita equations were used todetermine thecompression properties ofthetablets. Friability, crushing strength and thecrushing strength–friability ratio (CSFR) were used toevaluate themechanical properties ofthetablets, while dis¬solution times were used toevaluate drug release from thematrices. Thedrug release mechanisms were determined byfitting thedissolution data into classic kinetic equations. Results. Irvingia gabonensis polymer deformed plastically with afast onset and ahigh amount ofplastic deformation compared with xanthan gum and HPMC. This polymer was directly compressible and formed intact non-disintegrating tablets; themechanical and dissolution properties ofIrvingia gabonensis polymer tablets generally decreased with increasing concentration ofibuprofen. Theranking ofdissolution times was xanthan gum> freeze-dried Irvingia gabonensis> HPMC> oven-dried Irvingia gabonensis. Theaddition oftheexcipients improved themechanical properties ofthetablets, aided ibuprofen release, and altered therelease kinetics, which was largely defined bytheKorsmeyer–Peppas model. Increasing theproportion ofxanthan gum and HPMC inthematrices resulted inadecreased amount ofibuprofen released after 9h, with xanthan gum having agreater effect. Conclusions. Irvingia gabonensis polymer matrices may be effective inthepreparation ofcontrolled release tablets, and their right combination with xanthan gum orHPMC could provide atime-independent release for longer durations. 1 results 1
- CROPGRO-soya bean model 1 results 1
- Classroom 1 results 1
- Compression properties 1 results 1
- Contamination 1 results 1
- Controlled release 1 results 1
- Drought causes severe reduction in okra [Abelmoschus esculentus (L.) Moench] yield. However, the impact of drought on okra physiology has been impeding breeding where relative degrees of tolerance need to be quantified. The okra, cv. NHAe 47-4, was exposed to 25, 50, 75, or 100% field capacity (FC) to impose water deficit for 5 or 10 days, at the vegetative (V), vegetative and reproductive (VR), or reproductive (R) stages, and effects on growth and yield, leaf relative water content (LRWC), leaf photosynthetic pigments, proline, and cysteine accumulation assessed. Simulated drought reduced LRWC, leaf chlorophyll content, biomass accumulation, and okra growth compared to the control (100% FC). The effect was more severe on plants subjected to water deficit of 10 days duration at vegetative and reproductive stages at 25% FC. Plants treated at the vegetative stage alone recovered faster than those treated at the reproductive stage alone and treatment at the two stages together. After recovery, plants exposed to water deficit at the vegetative stage alone produced more chlorophyll than the control. Okra plants exposed to water deficit produced more proline, cysteine, and carotenoids than untreated plants, with the least recorded in control, and the response varied based on duration and different FC at every growth stage. The highest values for proline and carotenoids were at 25% FC for 10 days duration at every growth stage. Plants exposed to water deficit produced more fruit than the control, especially those exposed at the vegetative stage only. Under prolonged water deficit for 10 days at the vegetative stage, there was 90.95, 70.80, and 131.18% increase in fruit yield at 25, 50, and 75% FC, respectively, compared to the control. Soil water maintained at 75% FC throughout the growing period enhanced fruit production compared to other field capacities including control. Okra response depends on water deficit severity, duration, and growth stage. Production of proline and carotenoid could be a strategy employed by okra plants for tolerance under water deficit. 1 results 1
- Duration 1 results 1
- Growth 1 results 1
- Heavy Metals. 1 results 1
- Hibiscus cannabinus L. or kenaf is a fast growing and multipurpose annual crop planted for its horticultural and economie importance. Little is known about its response to different rates of organic fertilizer in Nigeria. The objective of thè study was therefore to evaluate thè effeets of different rates of commercially produced organic fertilizer (Aleshinloye organic fertilizer to be precise) on crop growth rate, vegetative growth and biomass accumulation in kenaf Five different rates of organic fertilizer equivalent to: 0, 70, 100, 130 and 160 kg N ha'1 replicated three times were used in a randomized complete block design (RCBD). There were contrasting results on thè effects of fertilizer rates on growth and physiology of kenaf. Significant effects were observed for some agronomie parameters such as plant height, stem diameter and fibre yield. The application of organic fertilizer at varying rates increased thè bast fibre yield of thè Ifeken 400 variety of kenaf troni 67.29 g/m2 (control) to 98.70, 147.88 and 157.40 g/ni2, in those grown on soil amended with 70, 100 and 130 kg N ha'1 of organic fertilizer respectively. Organic fertilizer could be utilized for thè cultivation of kenaf in Nigeria but thè rate to apply depends on thè nutrient content of thè organic fertilizer. 1 results 1
- High concentration of heavy metals in agricultural soils has been reported to affect plan physiological processes and seed germination. There is, therefore need to ameliorate the effect of metal toxicity on germinating seeds. Greenhouse and laboratory studies were carried out to determine the effect of mixing lead (Pb) contaminated soil with uncontaminated soil on seed germination as well as on the physiological process and morphological features of germinating seeds. Greenhouse experiment involved the mixing of lead contaminated soil with uncontaminated soil in ratios; 10:90, 25:75, 50:50, 75:25, 100:0 and 0:100 to give six soil types of 10, 25, 50, 75, 100 and 0% contamination respectively with four replications. Maize and Jathropha crops were used as test crops for the experiments. The leachates collected from the six soil types were used to carry out germination test in the laboratory. They were labelled as 0. 10, 25, 50, 75 and 100% contamination. Distilled water alone and 0% contamination were used as checks. The experiments were arranged using completely randomized design replicated three times. The results showed that the Pb concentration in this contaminated soil was very high (16,130.00 mg/kg). Though, soil mixing with contaminated soil reduced the soil Pb concentration compared to control (100% contamination). none of the mixtures could support seed germination. The laboratory experiment revealed that leachates from different soil mixtures also inhibit seed germination. There was 100% reduction in germination percentage, Water uptake by the seeds was reduced compared to control. There was shrinkage in the seeds sown in all the contaminated leachates. The nitrogen and protein contents of Jatropha seeds raised with the 100% contaminated soil were reduced compared to control (leachates from uncontaminated soil). However, there was an increase in nitrogen and protein contents of maize seeds raised with 100% lead-contaminated leachate as compared to control. High lead concentration in soils contaminated by lead acid battery wastes inhibits seed germination and induced plasmolysis. 1 results 1
- Hormones 1 results 1
- Intensity. Osmolytes 1 results 1
- Irvingia gabonensis 1 results 1
- Jatropha 1 results 1
- Kenaf 1 results 1
- Lead 1 results 1
- Learner 1 results 1
- Learning 1 results 1
- Learning as a dynamic task requires the synergy of various factors in order for the learner to benefit from the instruction being passed. Several factors could however impede on the successful transmission of ideas, as well as effective learning, among which is the learner’s innate ability, learning style, cultural background and emotional status. Also, an important factor affecting learning is the learner’s physiological makeup - some conditions that at times could present as a special need area and would require effective management for adequate learning to transpire. The author examined how learners with physiological peculiarities could be helped to learn appropriately in the classroom setting, and their learning problems ameliorated 1 results 1
- Maize 1 results 1
- Nitrogen is a major soil nutrient for the growth and development of crops. Nitrogen deficiency in-between pre-nodulation and nodulation in soya bean is critical to enhancing its growth and yield. Decision Support Systems for Agro-technology Transfer (DSSAT) model like CROPGRO-soya bean could be a useful tool for predicting starter nitrogen requirement in soya bean. However, information on starter nitrogen application to overcome N-deficiency-induced-stress during early seedling growth and prediction using CROPGRO-soya bean is limited. This study was undertaken to investigate the effect of starter nitrogen on soya bean yield grown on ferric luvisol in Oyo State, Nigeria.Field experiment involving two soya bean varieties (TGx1485-1D and TGx1448-2E) and five starter nitrogen rates (0, 5, 15, 25 and 35 kg/ha) was carried out for two seasons at Ipapo and Gbonran in Itesiwaju Local Government Area of Oyo State. The experiment was laid out as split-plot in a randomised complete block design with three replications. Nitrogen rate and soya bean variety were main and sub-plot factors, respectively. Shoot Dry Weight (SDW, t/ha), Grain Yield (GY, t/ha), Harvest Index (HI) and Shoot Nitrogen Content (SNC, g/kg) were measured. In screenhouse, soil from each location was filled into pots (5 kg) and each variety was planted under optimum management practices in a completely randomised design with three replications. Data on days to seedling emergence, days to first pod appearance and days to physiological maturity were obtained, fitted and used to calibrate CROPGRO-soya bean model. Data on weather parameters, soil description and characterisation (pH, field capacity, permanent wilting point, bulk density and hydraulic conductivity) were used for predicting phenology and yield. Data were analysed using ANOVA at α0.05, and model outputs were evaluated with percentage error (PE).Nitrogen rate had no significant effect on SDW, while variety TGx1448-2E had significantly higher SDW (2.9±0.3) and GY (1.5±0.1) than TGx1485-1D (2.3±0.3 and 1.3±0.1, respectively) at both locations. Nitrogen rate had no significant effects on GY and HI at Gbonran. However, 15 kgN/ha produced a significantly highest GY (1.4±0.1) than the control (1.2±0.1), while HI at 5 kgN/ha (0.60±0.02) was highest at Ipapo. Variety TGx1485-1D had significantly higher HI (0.58±0.05) than TGx1448-2E (0.52±0.05) at both locations. Nitrogen rate had no significant effect on SNC at both locations. Variety TGx1485-1D had significantly higher SNC (33.0±1.5) than TGx1448-2E (26.0±1.5) at Ipapo. CROPGRO-Soya bean model predicted soya bean phenology across nitrogen rates within 0 – 1 day of the observed values at both locations. Predicted yield of TGx1485-1D was 1.5 t/ha across N rates with PE < 15%, while that of TGx1448-2E was 2.6 t/ha with PE > 30%. Application of starter nitrogen had no effect on yields of soya bean at Gbonran but 15 kgN/ha enhanced grain yield of soya bean at Ipapo. Variety TGx1448-2E had better biomass yield, while TGx1485-1D had better nitrogen content on ferric luvisol. Prediction of CROPGRO-soya bean model was reliable for phenology and yield of TGx1485-1D but not reliable for yield of TGx1448-2E 1 results 1
- Organic Amendment 1 results 1
- Organic Fertilizer 1 results 1
- Osmolytes 1 results 1
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