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Common beans are rich in phenolic compounds, which can provide health benefits to the consumer. The objective of this work was to study the relationship among antimutagenicity, antioxidant and enzymatic activities of methanolic extract and trolox by principal components multivariate analysis. Antimutagenicity of phenolic compounds present in methanolic extract from the seed coat of common beans (P. vulgaris, Flor de Mayo Bajío cultivar) and trolox against AFB1 mutagenicity were evaluated in the Salmonella typhimurium microsuspension assay. Antioxidant capacity of methanolic extract and trolox were evaluated using β-carotene and 1,1-diphenyl-2-picryhydrazyl (DPPH) in vitro model assays. Cythrome P450 activity was measured by fluorometric assay. For phenolic extract, trolox and phenolic extract + trolox, the inhibition on AFB1 mutagenicity in tester strain TA100 was 47, 59 and 69%, respectively. While in TA98 was 39, 48 and 68%. The inhibition of phenolic compounds, trolox and phenolic compounds + trolox on cytochrome P450 (CYP450) activity was 48, 59 and 88%, respectively. Correlation analysis showed that phenolic extract and trolox have high antimutagenic and antioxidant activity and also inhibited enzymatic activity. The results suggest that the primary mechanism of action of phenolic compounds in beans against AFB1 mutagenicity may be extra-cellular in the microsuspension assay.  相似文献   
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Precision Agriculture - Crop monitoring through remote sensing techniques enable greater knowledge of average variability in crop growth. Canopy sensors help provide information on the variability...  相似文献   
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Aequipecten opercularis (Queen scallop) and Mimachlamys (Chlamys) varia (Black scallop) are important natural resources occurring in Atlantic and Mediterranean coasts. To develop an optimal sustainable exploitation plan, it is important to study the genetic structure of the different populations. In this study, we used polymerase chain reaction‐restriction fragment length polymorphisms for the determination of the genetic variation and population structure of these two species in different localities. Ten composite haplotypes were generated for A. opercularis and 15 haplotypes for M. varia. Of these, six and four were unique respectively. The analysis of the distribution of the different haplotypes between the localities showed no clear evidence of subdivision in A. opercularis, while in M. varia the results indicated that the two localities analysed should be managed as separate stocks.  相似文献   
5.
Behavioral and physiological traits of ectotherms are especially sensitive to fluctuations of environmental temperature. In particular, niche-specialist lizards are dependent on their physiological plasticity to adjust to changing environmental conditions. Lizards of the genus Phymaturus are viviparous, mainly herbivorous, and inhabit only rock promontories in the steppe environments of Patagonia and the Andes. Herein, we examine the vulnerability of the southernmost Phymaturus species to global warming: the endemic Phymaturus calcogaster, which lives in a mesic environment in eastern Patagonia. We studied body temperatures in the field (Tb), preferred body temperatures in a thermogradient (Tpref), the operative (Te) and environmental temperatures, and the dependence of running performance on body temperature. P. calcogaster had a mean Tb (27.04°C) and a mean Te (31.15°C) both lower than their preferred temperature (Tpref = 36.61°C) and the optimal temperature for running performance (To = 37.13°C). Lizard activity seems to be restraint during the early afternoon due high environmental temperatures. However, both, the high safety margin and warming tolerance suggest that the expected increase in environmental temperatures due to global warming (IPCC report in 2018) would not threaten, but indeed enhance locomotor performance in this population.  相似文献   
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In the present study, the validation of an enzyme-linked immunosorbent assay (ELISA) for serodiagnosis of canine brucellosis is described. Two different antigenic extracts, obtained by heat or ultrasonic homogenization of microbial antigens from a wild isolate of Brucella canis bacteria, were compared by ELISA and Western blot (WB). A total of 145 canine sera were used to define sensitivity, specificity and accuracy of the ELISA as follows: (1) sera from 34 animals with natural B. canis infection, confirmed by blood culture and PCR, as well as 51 sera samples from healthy dogs with negative results by the agar–gel immunodiffusion (AGID) test for canine brucellosis, were used as the control panel for B. canis infection; and (2) to scrutinize the possibility of cross reactions with other common dog infections in the same geographical area in Brazil, 60 sera samples from dogs harboring known infections by Leptospira sp., Ehrlichia canis, canine distemper virus (CDV), Neospora caninum, Babesia canis and Leishmania chagasi (10 in each group) were included in the study. The ELISA using heat soluble bacterial extract (HE-antigen) as antigen showed the best values of sensitivity (91.18%), specificity (100%) and accuracy (96.47%). In the WB analyses, the HE-antigen showed no cross-reactivity with sera from dogs with different infections, while the B. canis sonicate had various protein bands identified by those sera. The performance of the ELISA standardized with the heat soluble B. canis antigen indicates that this assay can be used as a reliable and practical method to confirm infection by this microorganism, as well as a tool for seroepidemiological studies.  相似文献   
7.
Evolution of resistance to herbicides in weeds is becoming an increasing problem worldwide. To develop effective strategies for weed control, a thorough knowledge of the basis of resistance is required. Although non‐target‐site‐based resistance is widespread, target site resistance, often caused by a single nucleotide change in the gene encoding the target enzyme, is also a common factor affecting the efficacies of key herbicides. Therefore, fast and relatively simple high‐throughput screening methods to detect target site resistance mutations will represent important tools for monitoring the distribution and evolution of resistant alleles within weed populations. Here, we present a simple and quick method that can be used to simultaneously screen for up to 10 mutations from several target site resistance‐associated codons in a single reaction. As a proof of concept, this SNaPshot multiplex method was successfully applied to the genotyping of nine variable nucleotide positions in the CT domain of the chloroplastic ACCase gene from Lolium multiflorum plants from 54 populations. A total of 10 nucleotide substitutions at seven of these nine positions (namely codons 1781, 1999, 2027, 2041 2078, 2088 and 2096) are known to confer resistance to ACCase‐inhibiting herbicides. This assay has several advantages when compared with other methods currently in use in weed science. It can discriminate between different nucleotide changes at a single locus, as well as screening for SNPs from different target sites by pooling multiple PCR products within a single reaction. The method is scalable, allowing reactions to be carried out in either 96‐ or 384‐well plate formats, thus reducing work time and cost.  相似文献   
8.
Ectophylla alba is a tent-making bat that roosts in mixed-sex clusters comprising adults and offspring. Our goal was to determine the genetic identity of individuals belonging to different roosting groups. We tested the hypothesis of kin selection as a major force structuring group composition. We used 9 microsatellites designed for E. alba to determine the genetic identity and probability of parentage of individuals. We analyzed parentage and kinship using the software ML-Relate, GenAIEx, and Cervus. The obtained relationship probabilities (0.5) revealed a clear maternal relationship between female adults and offspring with allele compatibility, and at least 5 relationships between male adults and pups. We found a low degree of relatedness within roosting groups. Between roosting groups at different sites, the mean probability of a half-sibling relationship ranged from 0.214 to 0.244 and, for full-sibling relationship, from 0.383 to 0.553. Genetically, adult individuals were poorly related within clusters, and kinship as an evolutionary force could not explain group membership.  相似文献   
9.
Objective: To (1) determine prevalence of radiographically detectable meniscal mineralization in domestic cats and (2) to evaluate the association between meniscal mineralization and degenerative joint disease (DJD). Study Design: Prospective study. Animals: Client‐owned cats (n=100) and 30 feline cadavers. Methods: Randomly selected client‐owned cats were used to determine the prevalence of meniscal mineralization. Stifles from feline cadavers were used to evaluate the relationship between meniscal mineralization (using high‐resolution X‐ray), radiographic DJD, and cartilage damage. Menisci were evaluated histologically. Results: Forty‐six percent of the client‐owned cats had meniscal mineralization detected in 1 or both stifles. Pain scores were not significantly different between stifles with meniscal mineralization and those with no radiographic pathology (P=.38). Thirty‐four of 57 cadaver stifles had meniscal mineralization, which was always located in the cranial horn of the medial meniscus. Percentage mineralization of the menisci was significantly correlated with the cartilage damage score of the medial femoral (r2=0.6; P<.0001) and tibial (r2=0.5; P<.0001) condyles as well as with the total joint cartilage damage (r2=0.36; P<.0001) score and DJD score (r2=0.8; P<.0001). Conclusion: Meniscal mineralization is a common condition in domestic cats and seems to indicate medial compartment DJD. Clinical Relevance: Clinical significance of meniscal mineralization is uncertain. Further work is needed to determine if the meniscal mineralization is a cause, or a consequence of joint degeneration.  相似文献   
10.
The probability of being employed varies depending on several factors. Many of these are related to personal characteristics such as educational level, age, gender, or number and age of children. Nevertheless, other factors may be relevant, in particular the geographical environment. The purpose of this paper is to analyse the relevance of urban size and the position of each territory (in terms of its distance from large metropolises) for the probability of being employed in the Spanish economy. Following the set of economic regions suggested by Polése, Shearmur and Rubiera (2007 ), we try to explain the spatial patterns of employment distribution. Our results show some relevant differences between these alternative economic areas. We find that municipalities with similar sizes and located at a similar distance from a metropolis but belonging to different Autonomous Communities or provinces share similar employability patterns.  相似文献   
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