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211.
Several new multifunctional molecules derived from natural sources such as amino acids and hydroxycinnamic acids were synthesized. They exhibit various activities such as emulsifying, UV-protecting, and radical scavenging, thereby conforming to the latest requirements for cosmetic ingredients. The synthesis comprises only a few steps: (i) the amino acid, the acid groups of which are protected by esterification, is coupled with ferulic or caffeic acid; (ii) the p-hydroxyl group of the cinnamic derivative reacts with dodecyl bromide in the presence of potassium carbonate (the resulting compounds are highly lipophilic and tested as water/oil (W/O) emulsifiers); (iii) these molecules, by deprotonating the acid groups of the amino acids, with successive salification, are more hydrophilic, with stronger O/W emulsifying properties. The new multifunctional surfactants might prove useful for the treatment of multiple skin conditions, including loss of cellular antioxidants, damage from free radicals, damage from UV, and others.  相似文献   
212.
Natural antibodies are an important component of innate humoral immunity but have not been investigated to any great extent in wild mammals. In the current study, serum natural antibody titres were measured by hemagglutination assay for two South American herbivores, the guanaco (Lama guanicoe) and the capybara (Hydrochoerus hydrochaeris). Results indicated that capybaras had antibody titres on average more than four times higher than guanacos (median titres 1:256 and 1:4, respectively), suggesting differences in investment in constitutive humoral immunity between the two species.  相似文献   
213.
The type VI secretion system (T6SS) is a virulence factor for many Gram-negative bacteria. Salmonella genus harbors five phylogenetically distinct T6SS loci encoded in Salmonella Pathogenicity Islands (SPIs) SPI-6, SPI-19, SPI-20, SPI-21 and SPI-22, which are differentially distributed among serotypes. The T6SSs encoded in SPI-6 and SPI-19 contribute to pathogenesis of serotypes Typhimurium and Gallinarum in mice and chickens, respectively. Salmonella Dublin is a pathogen restricted to cattle where it causes a systemic disease. Also, it can colonize other hosts such as chickens and mice, which can act as reservoirs of this serotype. Salmonella Dublin harbors the genes for both T6SSSPI-6 and T6SSSPI-19. This study has determined the contribution of T6SSSPI-6 and T6SSSPI-19 to host-colonization by Salmonella Dublin using avian and murine models of infection. Competitive index experiments showed that, a mutant strain lacking both T6SSs (∆T6SSSPI-6/∆T6SSSPI-19) presents a strong colonization defect in cecum of chickens, similar to the defect observed for the ∆T6SSSPI-6 mutant, suggesting that this serotype requires a functional T6SSSPI-6 for efficient colonization of the avian gastrointestinal tract. Colonization of mice was also defective, although to a lesser extent than in chickens. In contrast, the T6SSSPI-19 was not necessary for colonization of either chickens or mice. Transfer of T6SSSPI-6, but not T6SSSPI-19, restored the ability of the double mutant to colonize both animal hosts. Our data indicate that Salmonella Dublin requires only the T6SSSPI-6 for efficient colonization of mice and chickens, and that the T6SSSPI-6 and T6SSSPI-19 are not functionally redundant.  相似文献   
214.
Controlling infectious diseases at the wildlife/livestock interface is often difficult because the ecological processes driving transmission between wildlife reservoirs and sympatric livestock populations are poorly understood. Thus, assessing how animals use their environment and how this affects interspecific interactions is an important factor in determining the local risk for disease transmission and maintenance. We used data from concurrently monitored GPS-collared domestic cattle and wild boar (Sus scrofa) to assess spatiotemporal interactions and associated implications for bovine tuberculosis (TB) transmission in a complex ecological and epidemiological system, Doñana National Park (DNP, South Spain). We found that fine-scale spatial overlap of cattle and wild boar was seasonally high in some habitats. In general, spatial interactions between the two species were highest in the marsh-shrub ecotone and at permanent water sources, whereas shrub-woodlands and seasonal grass-marshlands were areas with lower predicted relative interactions. Wild boar and cattle generally used different resources during winter and spring in DNP. Conversely, limited differences in resource selection during summer and autumn, when food and water availability were limiting, resulted in negligible spatial segregation and thus probably high encounter rates. The spatial gradient in potential overlap between the two species across DNP corresponded well with the spatial variation in the observed incidence of TB in cattle and prevalence of TB in wild boar. We suggest that the marsh-shrub ecotone and permanent water sources act as important points of TB transmission in our system, particularly during summer and autumn. Targeted management actions are suggested to reduce potential interactions between cattle and wild boar in order to prevent disease transmission and design effective control strategies.

Electronic supplementary material

The online version of this article (doi:10.1186/s13567-014-0122-7) contains supplementary material, which is available to authorized users.  相似文献   
215.
Market-based fisheries management systems give incentives to reduce the fleet size and employment, which increases earnings and contributes to resolve the tragedy of the commons. However, the often-stated expectation that economies of scale cause the disappearance of small-scale fishery is not observed in many cases. In this study, we investigate the effects on fleet structure in the period after introducing individual fishing quotas or individual fishing days with various degrees of transferability in selected fisheries in the seven Nordic countries. Despite observing economies of scale in most cases, it is found that the market-based fisheries management often does not reduce the small-scale fleet more than the fleet of large vessels. This is explained partly by small vessels targeting demersal species and large vessels pelagic species, and partly by the larger need of larger than small vessels to continuously utilize their capital stocks through fast adaptation to ensure return. A more important explanation is the regulation design, with limitations in sale of fishing rights and lease between vessel groups and regions and in the share of the total quota holdings of fishing rights by individuals and vessels. This is important for countries considering the introduction of market-based fisheries management, since the Nordic experiences show that with proper regulation design, economic gains can be achieved with small-scale fishing surviving even under economies of scale.  相似文献   
216.
ABSTRACT

The squat lobster Munida gregaria has been recognized as a potential resource in several countries. However, data about its composition and nutritional value are scarce. This study provides information about the nutrients and nutritional quality of M. gregaria meat. Meat yield, proximate composition, cholesterol content, and fatty acid (FA) and amino acid (AAs) profiles were analyzed, and nutritional quality indexes were estimated. The average meat yield was 9.93%. The yearly average of the proximate composition of the M. gregaria meat (g/100 g meat) was moisture = 77.6, protein = 13.7, lipids = 3.84, and ash = 2.19. The average annual cholesterol content was 6.60 mg/100 g. The predominant FA (%) was C20:5ω3 (23.6), followed by C18:1ω9c (20.9), C22:6ω3 (18.5), and C16:0 (16.3); the unsaturated fatty acids were 72.8% of the total FA. The main AAs (g/100 g protein) were glutamic acid (15.1), leucine (9.47), and aspartic acid (8.51). Regarding the nutritional quality, the polyunsaturated FA/saturated FA ratio (1.99), ω3/ω6 ratio (8.62), atherogenic index (0.26), thrombotic index (0.56), hypocholesterolemic/hypercholesterolemic ratio (4.07), and polyene index (2.58) showed that M. gregaria meat provides lipids that are beneficial to the human diet. Moreover, M. gregaria meat provides high-quality proteins, which are well balanced in their essential AAs composition.  相似文献   
217.
218.

The fungus Macrophomina phaseolina, the causal agent of charcoal rot of common beans, damages the roots, stems, and leaves of seedlings and plants and forms resistant structures, so that chemicals are not sufficient for disease control. Integrated management systems associated with the use of biological control techniques are a sustainable alternative. Here we collected 37 native bacterial isolates from the common bean rhizosphere and screened them for antagonistic activity against M. phaseolina. Four isolates (BA97, BN17, BN20, and BR20) identified as Bacillus spp. showed antagonism in vitro against M. phaseolina, inhibiting its growth by 62.5–85%. In an in planta antagonistic assay, isolate BN20 reduced disease severity the most. Isolates BA97, BN17, BN20, and BR20 produced volatile compounds as a mechanism of antagonism. They also produced indole acetic acid in vitro (1.98–3.87 μg/ml). These results suggest that seed bacterization with the rhizobacterial isolates for field planting may be an effective means to reduce crop damage by M. phaseolina.

  相似文献   
219.
OBJECTIVE: To determine the diagnostic value of 2 intraoral bisecting angle radiographic views in comparison with periodontal probing for the assessment of periodontal attachment of the canine teeth in dogs. STUDY POPULATION: 466 canine teeth from 117 dogs. PROCEDURE: Periodontal probing measurements were recorded, and clinical attachment levels (CAL) were calculated at the mesial, buccal, distal, and lingual (or palatal) surfaces on each canine tooth. Occlusal and lateral radiographs of the canine teeth were obtained. Alveolar margin height (AMH) was measured at the same 4 surfaces. Values for AMH and CAL were compared on the basis of tooth surface, dental arch, and radiographic view. RESULTS: The AMH at the mesial and distal surfaces of the mandibular canine teeth was measurable on the lateral view and was significantly correlated with CAL. Similar results were found for the mesial and distal surfaces of the maxillary canine teeth. Buccal and lingual AMH were measured on the mandibular occlusal radiographic view, and values were significantly correlated with CAL, but only the buccal AMH could be assessed on the occlusal radiographic view of the maxilla with values that correlated significantly with CAL. CONCLUSIONS AND CLINICAL RELEVANCE: The lateral radiographic view is suitable for evaluating periodontal attachment at the mesial and distal surfaces of the canine teeth in dogs. The occlusal radiographic view is suitable for assessing buccal surfaces as well as the lingual surface of mandibular canine teeth but not the palatal surface of maxillary canine teeth in dogs.  相似文献   
220.
A 9-year-old, intact male Doberman Pinscher was examined because of anorexia and weakness. Results of a CBC showed severe, microcytic, hypochromic anemia with mild eosinophilia (2944 cells/microL, reference interval 100-1250/microL) and thrombocytosis. Hypoferremia, hypoferritinemia, and a positive fecal occult blood test supported a diagnosis of iron deficiency anemia secondary to chronic intestinal hemorrhage. Abdominal ultrasound evaluation showed a thickened small intestinal loop, of which representative specimens were obtained during exploratory laparotomy. Histologically, the intestinal wall was infiltrated by a neoplastic population of large, round, lymphoid cells with vesicular chromatin, 1 or more prominent nucleoli, and a high number of mitotic figures. The cells were closely admixed with mature eosinophils, but were negative for metachromatic granules with toluidine blue. Immunohistochemically, tumor cells were positive for CD3, and negative for CD21, Pan B, and CD79a. A diagnosis of intestinal T-cell lymphoma was made. Chemotherapy was begun, with 30 mg/m;2 of doxorubicin administered intravenously every 3 weeks. Eosinophil concentration was 880/microL 2 weeks after surgery (on day 15 after presentation) but increased markedly to 62,914/microL on day 30, 62,400/microL on day 37, and 39,444/microL on day 58 after presentation. An association between hypereosinophilia and T-cell lymphoma is well established in human patients, in whom production of IL-5 by neoplastic T cells has been demonstrated. Hypereosinophilia has been reported only rarely with intestinal lymphoma in cats and horses, and with T-cell lymphoma in dogs.  相似文献   
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