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101.
Fetal lung produces corticotropin-releasing hormone (CRH) without known direct effects. We tested the hypothesis that CRH can directly regulate lung development. In baboon fetal lung explants, CRH strongly induces surfactant phospholipid synthesis and SP-C immunostaining, plus [3H]thymidine incorporation. CRH receptor mRNA was detected in lung from multiple baboons at e125. Testing thyrotropin (TRH) as a specificity control, we did demonstrate different direct effects with only modest stimulation of surfactant phospholipid synthesis and strong induction of cytidylyltransferase gene expression. Therefore, CRH, similar to ACTH and glucocorticoids, is a potent inducer of cell differentiation in fetal lung.  相似文献   
102.
Fungi isolated from skins and pens of healthy animals in Nigeria   总被引:5,自引:0,他引:5  
The mycoflora of 220 skin scrapings, hair, nail samples and pens’ materials of apparently healthy animals including cows, sheep, goats, rabbits, pigs and dogs were determined. Twenty eight species of fungi belonging to ten genera were recovered. Chrysosporium spp. were the most common and C. keratinophilum was recovered from all animals. Dermatophytes which are known causal agents of dermatophytosis were also isolated indifferent frequencies (Microsporum gypseum, M. canis, Trichophytonmentagrophytes, T. rubrum). This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   
103.
Composting technology has been widely used as a cost-effective, eco-friendly, and efficient solid waste management option for the bioremediation of organic pollutants. Most studies have focused on the use of compost in the bioremediation of organic pollutants, without any attention being paid to the effect of the organic pollutants on the composting process. Therefore, in this study, the effect of an organic pollutant (anthracene) on a starch-amended composting process is reported. In order to determine the effect, the total dry matter and the extracellular enzyme analysis (EEA) of starch-specific (α-glucosidase) and -nonspecific (β-glucosidase) substrates were monitored. Over the course of the experiments, there appeared to be some form of anthracene effect on the progression in the total dry matter and the extracellular enzyme analysis (EEA) of the α-glucosidase, particularly in the starch and anthracene–amended composts. The interactions between the starch and the anthracene consistently increased the total dry matter and the α-glucosidase activity of the starch and anthracene–amended composts. This observation is novel, and the kind of interaction is yet unknown. Therefore, detailed investigation to understand the magnitude of such interaction is necessary to potentially resolve these issues.  相似文献   
104.
Twelve new derivatives of benzothiazole bearing benzenesulphonamide and carboxamide were synthesised and investigated for their in vivo anti-inflammatory, analgesic and ulcerogenic activities. Molecular docking showed an excellent binding interaction of the synthesised compounds with the receptors, with 17c showing the highest binding energy (–12.50?kcal/mol). Compounds 17c and 17i inhibited carrageenan-induced rat paw oedema at 72, 76, and 80% and 64, 73, and 78% at 1?h, 2?h, and 3?h, respectively. In the analgesic activity experiment, compounds 17c, 17?g, and 17i had ED50 (µM/kg) of 96, 127, and 84 after 0.5?h; 102, 134, and 72 after 1?h and 89, 156, and 69 µM/kg after 2?h, respectively, which were comparable with 156, 72, and 70 µM/kg for celecoxib. The ulcerogenic index of the most active derivatives 17c and 17i were 0.82 and 0.89, respectively, comparable to 0.92 for celecoxib. The physicochemical studies of the new derivatives showed that they will not have oral bioavailability problems.  相似文献   
105.
A plant that showed morphological closeness to Aspilia africana (Pers) C. D. Adams (Asteraceae) was spotted and collected in 2015 along Afe Babalola University road, Ado‐Ekiti, Ekiti State, Nigeria with coordinates 7°36′59.99″N, 5°12′60.00″E. However, upon closer observation some distinct and peculiar characteristics that clearly distinguished it from Aspilia africana were revealed, e.g. sterility of the disc florets and production of achenes by ray florets only. Another striking character of the plant was total emptying of the capitulum after achene maturation, leaving an empty capitulum cup on the plant. Literature and herbarium searches revealed that the plant had neither been reported from West Tropical Africa nor collected in any herbarium in Nigeria before. The plant was eventually identified as Melampodium divaricatum (L.) which is an annual erect herb, distributed in tropical and subtropical regions but mostly restricted to Mexico, North America and Central America. Morphological, reproductive and cytological studies carried out on the plant revealed it to possess a highly branched erect pigmented stem, simple opposite sub sessile leaves with acute apex and distantly serrated margins, capitula with yellow unisexual disc and ray florets, sterile disc florets, fertile ray florets, relatively high pollen fertility (92.85%), a somatic chromosome number of 2n = 24 and regular formation of 12 bivalents, indicating the plant to be a diploid species. Further studies on Melampodium in Nigeria and a general revision of the flora of West Tropical Africa is suggested as well as the need to monitor M. divaricatum in the region since it appears to have the capacity to become invasive.  相似文献   
106.
Women with the breast cancer type 1 susceptibility protein (BRCA1) mutation and loss of BRCA1 expression are reported to have an increased risk of triple-negative breast cancer (TNBC). Targeting BRCA1 modulation might offer a therapeutic option to treat TNBC patients. Our studies detected that BRCA1 is poorly expressed in TNBC cell lines and highly expressed in ER+ breast cancer cell lines. To modulate BRCA1 expression, we tested two different dietary components to find out if any would induce tumor suppressor genes. We detected that quercetin and curcumin dose-dependently enhanced the BRCA1 expression. Further, a synergistic action of quercetin and curcumin was observed in modulating the BRCA1 level and in inhibiting the cell survival and migration of TNBC cell lines. Quercetin and curcumin appeared to induce BRCA1 promoter histone acetylation. Furthermore, BRCA1 knockdown induced cell survival and cell migration in ER + cells were significantly decreased by the combined treatment of quercetin and curcumin. Our present study concluded that the combination treatment of quercetin and curcumin acts synergistically to induce anticancer activity against TNBC cells by modulating tumor suppressor genes.  相似文献   
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109.
Variation in tandem repeats of two- to six-base nucleotide motifs (microsatellites) can be used to obtain inexpensive and highly informative multi-locus data on population genetics.We developed and tested a large set of cross-amplifiable sea star (Asterinidae) microsatellite markers from a mixed pool of genomic DNA from eight species. We describe cloned sequences, primers, and PCR conditions, and characterize population-level variation for some species and markers. A few clones containing microsatellites showed considerable similarity to sequences (including genes of known function) in other sea stars and in sea urchins (from the Strongylocentrotus purpuratus complete genome). The pooled genomic DNA method was an efficient way to sample microsatellites from many species: we cloned 2-10 microsatellites from each of eight species, and most could be cross-amplified in 1-7 other species. At 12 loci in two species, we found 1-10 alleles per microsatellite, with a broad range of inbreeding coefficients. Measures of polymorphism were negatively correlated with the extent of cross-amplification.  相似文献   
110.
The pathogenicity of four isolates each of the entomopathogenic fungi, Beauveria bassiana (Bals.) Vuill. and Metarhizium anisopliae (Metsch.) Sorok. to apterous adult Aphis craccivora Koch was evaluated in the laboratory at 4 concentrations of conidia. All fungi isolates tested were found to be pathogenic to the insect but their virulence varied among species and isolates within species. Three isolates, B. bassiana CPD 11 and M. anisopliae CPD 4 and 5 caused significantly higher mortality than the other isolates at the various concentrations tested causing mortality of between 58–91%, 64 to 93% and 66–100%, respectively, at 7 days post treatment. At the highest concentration of 1 × 108conidiaml‐1, these isolates produced the shortest LT50s of 3.5, 3.6 and 3.4 days, respectively. Their LC50s were 6.8 × 105, 3.1 × 105 and 2.7 × 105 conidia ml‐1, respectively. The results indicate that these isolates are promising candidates for the control of the cowpea aphid but their pathogenicity to various aphid non‐target beneficial organisms within the cowpea agroecosystem warrant further investigation before initiating field control.  相似文献   
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