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1.
The Trypanosoma spp. cause animal and human trypanosomiasis characterized with appreciable health and economic burden mostly in developing nations. There is currently no effective therapy for this parasitic disease, due to poor drug efficacy, drug resistance, and unwanted toxicity, etc. Therefore, new anti-Trypanosoma agents are urgently needed. This study explored new series of imidazoles for anti-Trypanosoma properties in vitro and in vivo. The imidazoles showed moderate to strong and specific action against growth of T. congolense. For example, the efficacy of the imidazole compounds to restrict Trypanosoma growth in vitro was ≥ 12-fold specific towards T. congolense relative to the mammalian cells. Additionally, the in vivo study revealed that the imidazoles exhibited promising anti-Trypanosoma efficacy corroborating the in vitro anti-parasite capacity. In particular, three imidazole compounds (C1, C6, and C8) not only cleared the systemic parasite burden but cured infected rats after no death was recorded. On the other hand, the remaining five imidazole compounds (C2, C3, C4, C5, and C7) drastically reduced the systemic parasite load while extending survival time of the infected rats by 14 days as compared with control. Untreated control died 3 days post-infection, while the rats treated with diminazene aceturate were cured comparable to the results obtained for C1, C6, and C8. In conclusion, this is the first study demonstrating the potential of these new series of imidazoles to clear the systemic parasite burden in infected rats. Furthermore, a high selectivity index of imidazoles towards T. congolense in vitro and the oral LD50 in rats support anti-parasite specific action. Together, findings support the anti-parasitic prospects of the new series of imidazole derivatives.  相似文献   
2.
Naja haje envenoming could activate multiple pathways linked to haematotoxic, neurological, and antioxidant systems dysfunctions. Moringa oleifera has been used in the management of different snake venom-induced toxicities, but there is no scientific information on its antivenom effects against Naja haje. This study thus, investigated the antivenom activities of different extract partitions of M. oleifera leaves against N. haje envenoming. Forty five male rats were divided into nine groups (n = 5). Groups 2 to 9 were envenomed with 0.025 mg/kg (LD50) of N. haje venom while group 1 was given saline. Group 2 was left untreated, while group 3 was treated with polyvalent antivenom, groups 4, 6 and 8 were treated with 300 mg/kg?1 of N-hexane, ethylacetate and ethanol partitions of M. oleifera, respectively. Groups 5, 7 and 9 were also treated with 600 mgkg?1of the partitions, respectively. Ethanol extract and ethyl acetate partition of M. oleifera significantly improved haematological indices following acute anaemia induced by the venom. Likewise, haemorrhagic, haemolytic and anti-coagulant activities of N. haje venom were best inhibited by ethanol partition. Envenoming significantly down-regulated Nuclear factor erythroid 2-related factor 2 (Nrf2) with the consequent elevation of antioxidant enzymes activities in the serum and brain. Treatment with extract partitions however, elevated Nrf2 levels while normalising antioxidant enzyme activities. Furthermore, there were reduction in levels of pro-inflammatory cytokines (TNF-α and interleukin-1β) in tissues of treated envenomed rats. This study concludes that ethanol partition of M. oleifera was most effective against N. haje venom and could be considered as a potential source for antivenom metabolites.  相似文献   
3.
This present research investigated variations in lipid profiles and important biomarkers of tissue damage in response to graded concentrations of alcohol administration in male Wistar rats. Group A (control) received distilled water while group B, C and D received 30%, 40% and 50% (v/v) alcohol respectively. Five rats each from groups A-D were sacrificed after day(s) 1, 7, 14, 21 and 28 of administration. A significant increase was observed at day 28 for serum cholesterol by 79% (group B), 78% (group C) and 47% (group D) together with serum phospholipid 58% (group B), 50% (group C) and 92% (group D). Serum triacylglycerol increased by 71% (group B), 43% (group C) and 16% (group D) at day 21, while concentration of serum albumin decreased at day 28 by 40.9% (group B), 50.2% (group C), 53.3% (group D) respectively when compared with control (group A). Serum aminotransferases and alkaline phosphatase specific activities, as well as creatinine and uric acid concentration increased in a concentration-dependent manner, following alcohol administration. Though most of these effects induced by alcohol were time- and concentration-dependent, 40% alcohol appear to be more stable, giving results consistent with alcohol-induced damages, with minimal mortality. This study therefore further validated dyslipidemia and imbalance in clinical biomarkers as hallmarks of tissue damage induced by excessive alcohol consumption with an insight on the time- and concentration-response relationship between alcohol consumption and its toxicity.  相似文献   
4.
Sperm competition represents an important component of post-copulatory sexual selection. It has been argued that the level of sperm competition declines in birds towards the equator. However, to date, sperm competition estimates have been available mainly for avian species inhabiting the northern temperate zone. Here we apply a novel approach, using the coefficient of between-male variation (CVbm) in sperm size as an index for sperm competition risk, in a comparative analysis of 31 Afrotropical and 99 northern temperate zone passerine species. We found no difference in sperm competition risk between the two groups, nor any relationship with migration distance. However, a multivariate model indicated that sperm competition risk was highest in species with a combination of low body mass and few eggs per clutch. The effect of clutch size was most pronounced in tropical species, which indicates that sperm competition risk in tropical and temperate species is differently associated with particular life-history traits. Although tropical species had lower sperm competition risk than temperate zone species for overlapping clutch sizes, the idea of a generally reduced risk of sperm competition in tropical birds was not supported by our analysis.  相似文献   
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6.
Sclerotinia sclerotiorum is a pathogenic fungus that infects hundreds of plant species, including many of the world's most important crops. Key features of S. sclerotiorum include its extraordinary host range, preference for dicotyledonous plants, relatively slow evolution, and production of protein effectors that are active in multiple host species. Plant resistance to this pathogen is highly complex, typically involving numerous polymorphisms with infinitesimally small effects, which makes resistance breeding a major challenge. Due to its economic significance, S. sclerotiorum has been subjected to a large amount of molecular and evolutionary research. In this updated pathogen profile, we review the evolutionary and molecular features of S. sclerotiorum and discuss avenues for future research into this important species.  相似文献   
7.
Tribolium confusum is a major pest of grains and grain products. Some legumes hitherto not used as major food are gaining interest due to increase in human population and the need of food and feeds. Susceptibility of fresh and processed Glycine max and Cajanus cajan flours, and white wheat flour (control) to T. confusum was studied towards effective storage techniques and cheap insect diet. Ten copulating pairs of the beetle were introduced into twenty grams of each flour. Number of eggs laid, emerged larvae, pupae, eclosed adults, and duration of development of each stage was used as indices of survival of T. confusum. Proximate composition, saponin; and α-amylase and protease inhibitors determined suitability of flours as insect diet. This work discusses the significance of proximate composition and anti-nutrient properties in fresh and roasted processed flours on the development and survival of T. confusum.  相似文献   
8.
In bridging the knowledge gap on stress physiology of Nigerian indigenous chickens, this study investigated the effect of exogenous corticosterone (eCORT) as stress inducing agent on the testicular function and mating behavior of Nigerian indigenous cocks. Twenty-four (24) cocks and one hundred and forty four (144) hens (mating ratio of 1 cock: 6 hens) were grouped into four and assigned to each of the four eCORT treatments (0, 2, 4 and 6 mgeCORT/KgBW) daily for 14 days. Semen samples were collected on days 0, 7 and 14 and analyzed for semen volume (SV), progressive sperm motility (PSM), membrane integrity (MI) and sperm abnormality (SA). Mating behaviors were monitored on days 3, 5 and 8. Blood samples, for hormonal (Luteinizing Hormone (LH), Follicle Stimulating Hormone (FSH) Testosterone (TEST) and stress analysis (heterophil/lymphocyte ratio, H/L) were collected from brachial vein on days 7 and 14. On day 15, cocks were euthanized and testes harvested for histomorphometry. Data were analyzed using multivariate analysis, one–way ANOVA and Kruskal-Wallis tests all in SPSS 23. Administration of 4 mgeCORT/KgBW declined (P<0.05) PSM while 4 mgeCORT/KgBW and 6 mgeCORT/KgBW cocks had reduced (P<0.05) SV and MI with increased SA. Compared to baseline values, progressive sperm motility of cocks administered 6 mgeCORT for 7 and 14 days decreased (P<0.05) by 57.5% and 52.4%, respectively. Exogenous CORT had no significant (P>0.05) influence on the mating behaviors, H/L ratio, FSH and TEST. However, 2 mgeCORT/KgBW enhanced LH levels. Administration of eCORT did not affect the testicular epithelial height and seminiferous tubular diameter. In conclusion, optimal stress induced by eCORT impaired semen quality but with less impact on reproductive hormones, H/L and mating behaviors of intensively raised Nigerian indigenous cocks.  相似文献   
9.
Supercoiled plasmid pBR322 DNA was irradiated in phosphate buffer by 60Co gamma-rays at a dose rate 19.26 Gy/min and total dose of 10 Gy in the presence of a bioreductive antitumour prodrug namely 1,4-bis [?2-(dimethylamino-N-oxide)ethyl? amino] 5, 8-dihydroxyanthracene-9,10-dione (AQ4N) and its DNA affinic reduction product 1,4-bis[?2(dimethylamino)ethyl? amino] 5,8-dihydroxyanthracene-9,10-dione (AQ4) under air and nitrogen. AQ4N and AQ4 were found to protect against radiation-induced plasmid single and double strand breakage as assessed by agarose gel electrophoresis. The differences between the two agents, and between atmospheres of air or nitrogen were negligible. It was also found that the protection efficiencies of the compounds were pH dependent and showed maximum protection at pH 6. These results indicate that protection of DNA by AQ4 and AQ4N against radiation damage is an indirect effect since both agents are equally effective despite major differences in their DNA affinity. It is likely that radiation-induced phosphate buffer radicals are intercepted by AQ4 and AQ4N in a pH-dependent process.  相似文献   
10.
Evaluation of various agro-wastes for traditional black soap production   总被引:1,自引:0,他引:1  
The agricultural wastes, cocoa-pod husks, palm-bunch waste, sorghum chaff and groundnut shells, which are normally thrown away have been used in the production of black soap. Unlike other soaps which are made from oils and chemicals, black soap is made from oils and agro-wastes ashes. Chemical analysis indicated that the liquid extract from the ashes of the different agro-wastes used contained various amounts of potassium and sodium compounds. The most common ingredient in the agro-wastes was potassium carbonate. The amount of potassium carbonate was 56.73 +/- 0.16% in cocoa-pod ash, 43.15 +/- 0.13% in palm-bunch ash, 16.65 +/- 0.05% in groundnut shell ash and 12.40 +/- 0.08% in sorghum chaff ash. Soaps made from the agro-wastes ashes had excellent solubility, consistency, cleansing and lathering abilities.  相似文献   
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