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1.
Sclerotium rolfsii Sacc. is an important fungal pathogen affecting the production of tomato (Lycopersicon esculentum Mill.). Conventional control methods using chemicals are expensive, which constitute environmental hazards. This has necessitated the search for alternatives in botanicals. Ethanol and supernatant solution of fermented maize slurry extracts from Ocimum gratissimum, Cymbopogon citratus, Xylopia aethiopica, Aframomum melegueta and Allium sativum were evaluated. In vitro test was carried out at 1, 2, 3, 4 and 5% concentrations against the pathogen. Mycelial growth was significantly reduced in the following descending order: O. gratissimum?>?A. melegueta?>?A. sativum?>?X. aethiopica?>?C. citratus. Supernatant solution extracts of O. gratissimum and A. melegueta at 5% concentration gave highest mycelial reduction (0.00?mm), respectively, while O. gratissimum ethanol extract recorded highest mycelial reduction (0.23?mm) among the ethanol extracts. Supernatant solution of fermented maize slurry extracts of O. gratissimum and A. melegueta at 5% concentration was more effective in reducing mycelial growth of S. rolfsii.  相似文献   
2.
This study was conducted to examine the psycho-emotional effects of repeated oral exposure to capsaicin, the principal active component of chili peppers. Each rat received 1 mL of 0.02% capsaicin into its oral cavity daily, and was subjected to behavioural tests following 10 daily administrations of capsaicin. Stereotypy counts and rostral grooming were significantly increased, and caudal grooming decreased, in capsaicin-treated rats during the ambulatory activity test. In elevated plus maze test, not only the time spent in open arms but also the percent arm entry into open arms was reduced in capsaicin-treated rats compared with control rats. In forced swim test, although swimming duration was decreased, struggling increased in the capsaicin group, immobility duration did not differ between the groups. Repeated oral capsaicin did not affect the basal levels of plasma corticosterone; however, the stress-induced elevation of plasma corticosterone was prolonged in capsaicin treated rats. Oral capsaicin exposure significantly increased c-Fos expression not only in the nucleus tractus of solitarius but also in the paraventricular nucleus. Results suggest that repeated oral exposure to capsaicin increases anxiety-like behaviours in rats, and dysfunction of the hypothalamic-pituitary-adrenal axis may play a role in its pathophysiology.  相似文献   
3.

Background:

Vascular growth is a prerequisite for adipose tissue (AT) development and expansion. Some AT cytokines and hormones have effects on vascular development, like vascular endothelial growth factor (VEGF‐A), angiopoietin (ANG‐1), ANG‐2 and angiopoietin‐like protein‐4 (ANGPTL‐4).

Methods:

In this study, the independent and combined effects of diet‐induced weight loss and exercise on AT gene expression and proteins levels of those angiogenic factors were investigated. Seventy‐nine obese males and females were randomized to: 1. Exercise‐only (EXO; 12‐weeks exercise without diet‐restriction), 2. Hypocaloric diet (DIO; 8‐weeks very low energy diet (VLED) + 4‐weeks weight maintenance diet) and 3. Hypocaloric diet and exercise (DEX; 8‐weeks VLED + 4‐weeks weight maintenance diet combined with exercise throughout the 12 weeks). Blood samples and fat biopsies were taken before and after the intervention.

Results:

Weight loss was 3.5 kg in the EXO group and 12.3 kg in the DIO and DEX groups. VEGF‐A protein was non‐significantly reduced in the weight loss groups. ANG‐1 protein levels were significantly reduced 22‐25% after all three interventions (P < 0.01). The ANG‐1/ANG‐2 ratio was also decreased in all three groups (P < 0.05) by 27‐38%. ANGPTL‐4 was increased in the EXO group (15%, P < 0.05) and 9% (P < 0.05) in the DIO group. VEGF‐A, ANG‐1, and ANGPTL‐4 were all expressed in human AT, but only ANGPTL‐4 was influenced by the interventions.

Conclusions:

Our data show that serum VEGF‐A, ANG‐1, ANG‐2, and ANGPTL‐4 levels are influenced by weight changes, indicating the involvement of these factors in the obese state. Moreover, it was found that weight loss generally was associated with a reduced angiogenic activity in the circulation.  相似文献   
4.
5.
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   
6.
Ubiquitination is a universal protein degradation pathway in which the molecules of 8.5-kDa proteolytic peptide ubiquitin are covalently attached to the epsilon-amino group of the substrate's lysine residues. Little is known about the importance of this highly conserved mechanism for protein recycling in mammalian gametogenesis and fertilization. The data obtained by the students and faculty of the international training course Window to the Zygote 2000 demonstrate the accumulation of ubiquitin-cross-reactive structures in the trophoblast, but not in the inner cell mass of the expanding bovine and mouse blastocysts. This observation suggests that a major burst of ubiquitin-dependent proteolysis occurs in the trophoblast of mammalian peri-implantation embryos. This event may be important for the success of blastocyst hatching, differentiation of embryonic stem cells into soma and germ line, and/or implantation in both naturally conceived and reconstructed mammalian embryos.  相似文献   
7.
Two new naphthalene acylglucosides, rumexneposides A (1) and B (2), together with 12 known compounds (3-14), were isolated from the roots of Rumex nepalensis. Their structures were established by chemical and spectroscopic methods. The biological activities of compounds 1-14 as well as an additional 11 compounds previously isolated from R. nepalensis and Rumex hastatus (15–25) were evaluated against Mycobacterium tuberculosis, para-aminobenzoic acid (pAba) pathway, and a panel of human cancer cell lines. The results showed that compound 15 was the most active against M. tuberculosis with an MIC value of 2.85 μM similar to that of isoniazid. Compound 5 could inhibit pAba synthetic pathway with an MIC value of 12.6 μM, comparable to that of positive control abyssomicin C, representing a new example of the rare pAba pathway inhibitors.  相似文献   
8.

Background  

The present study was designed to examine the effect of chronic treatment with rosiglitazone - thiazolidinedione used in the treatment of type 2 diabetes mellitus for its insulin sensitizing effects - on the Leydig cell steroidogenic capacity and expression of the steroidogenic acute regulatory protein (StAR) and cholesterol side-chain cleavage enzyme (P450scc) in normal adult rats.  相似文献   
9.
This study assessed the effects of genotype variations in two cultivated rice species: Oryza glaberrima and Oryza sativa on the biology and galling characteristics of the African rice gall midge (AfRGM), Orseolia oryzivora Harris and Gagné. The study was conducted in the screen house at ambient temperature (27 ± 3°C), 70 ± 5% relative humidity and 12:12 h photoperiod. Shoot galling, the most visible response of rice genotypes to attack by the insect, was greatly suppressed, being only 0.7 cm long in the O. glaberrima genotypes compared to 34 cm in the O. sativa species. Larval mortality (70–88%) in the O. glaberrima genotypes was significantly higher at the first instar compared to O. sativa. Gall setting was confirmed to be an irredeemable tiller loss. Even in the susceptible O. sativa genotypes, where many larvae may colonize a tiller, only one survived to the second instar. Resistant and susceptible rice genotypes had significantly different effects on the development and reproductive anatomy of the AfRGM. The female reproductive anatomy which consists of two ovaries, each with a potential complement of 192 eggs was affected by interspecific variation in rice genotypes causing reduced potential fecundity (32); morphological distortion, 60% reduction of egg size of F1 emergent in O. glaberrima compared to emergent from the susceptible O. sativa genotypes.  相似文献   
10.
The mammalian nucleus has a distinct substructure that cannot be visualized directly by conventional microscopy. In this study, the organization of the DNA within the nucleus of multiple myeloma (MM) cells, their precursor cells (monoclonal gammopathy of undetermined significance; MGUS) and control lymphocytes of the representative patients is visualized and quantified by superresolution microscopy. Three‐dimensional structured illumination microscopy (3D‐SIM) increases the spatial resolution beyond the limits of conventional widefield fluorescence microscopy. 3D‐SIM reveals new insights into the nuclear architecture of cancer as we show for the first time that it resolves organizational differences in intranuclear DNA organization of myeloma cells in MGUS and in MM patients. In addition, we report a significant increase in nuclear submicron DNA structure and structure of the DNA‐free space in myeloma nuclei compared to normal lymphocyte nuclei. Our study provides previously unknown details of the nanoscopic DNA architecture of interphase nuclei of the normal lymphocytes, MGUS and MM cells. This study opens new avenues to understanding the disease progression from MGUS to MM. J. Cell. Biochem. 116: 704–710, 2015. © 2014 The Authors. Journal of Cellular Biochemistry published by Wiley Periodicals, Inc.  相似文献   
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