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101.
Iron-dependent outer membrane proteins (IROMPs) play an important role in bacterial pathogenesis and present several attributes of potential vaccine candidates. TBLASTN analysis of the Pasteurella multocida Pm70 genome using the same molecules of other bacterial pathogens as a query identified eight putative haemin and haemoglobin receptors for this organism. Quantitative binding assays have demonstrated that the proteins PM0040, PM0236, PM0741, PM1081, PM1428, PM0592 and HgbA bind both haemin and haemoglobin, whereas PM0576 and PM1282 ORFs only bind either haemoglobin or haemin, respectively. Furthermore, Western blot analysis showed that P. multocida-infected mice generate specific antibodies against PM0040, PM0236, PM0741, PM1081, PM1428, PM0592 and HgbA proteins. Nevertheless, inoculation of mice with any single one of these receptors alone did not protect against P. multocida infection.  相似文献   
102.
Although some ELISA tests using cytoplasmic or outer membrane antigens of Brucella have been developed to improve the diagnosis of canine brucellosis, the performance of these assays has not been compared. In the present study three ELISA tests using lipopolysaccharide (LPS)-free cytoplasmic proteins (CPs) of Brucella abortus, the lumazine synthase (LS) of Brucella spp. or a hot-saline (HS) extract of Brucella canis containing outer membrane antigens were used to test sera from dogs with suspected or confirmed brucellosis (n=36) and from dogs with pathological conditions other than brucellosis (n=212). In the first group the proportion of positive results was 92, 92 and 81% for the ELISAs with HS, CP and LS, respectively, and 94% of the samples were positive by at least one ELISA test. Three dogs that were negative by agglutination (2ME-RSAT) had a positive result by at least one ELISA, and this discrepancy was attributed to the lower analytical sensitivity of agglutination tests. This hypothesis was confirmed by a serological follow-up of seven dogs recently infected with B. canis in three of which the illness was diagnosed earlier by one or more ELISA tests than by 2ME-RSAT. Among dogs having pathological conditions other than brucellosis, specificities were 94.3, 96.7 and 96.7% for the ELISAs with HS, CP and LS, respectively. This study shows that HS-ELISA and CP-ELISA are highly specific and sensitive for the diagnosis of canine brucellosis and can detect the infection by B. canis shortly after the exposure to the pathogen.  相似文献   
103.
Tocopherols are compounds present in oilseeds with major effect on nutritional and technological properties of seed oils. Brassica spp. mainly contain varying concentrations of α‐tocopherol, with high vitamin E value, and γ‐tocopherol, which contributes to oil stability. The objective of this research was to select for contrasting tocopherol content and profile in Ethiopian mustard (Brassica carinata A. Braun). A collection of 211 F4:5 lines was evaluated for tocopherol content and profile, and divergent selection was conducted till the S3:4 generation. Selection resulted in two lines with increased tocopherol content (244 and 243 mg/kg seed as average of four environments), one line with reduced tocopherol content (117 mg/kg), two lines with reduced α/γ‐tocopherol ratio (0.22 and 0.28) and two lines with increased α/γ‐tocopherol ratio (3.74 and 3.34). Control line C‐101 averaged 196 mg/kg with α/γ‐tocopherol ratio of 1.10. Reduced α/γ‐tocopherol ratio was controlled by recessive alleles at a single locus. Seed to plant correlation was high (r = 0.92), which suggests the feasibility of selecting at the single‐seed level.  相似文献   
104.
ObjectiveTo compare tidal volume estimations obtained from Respiratory Ultrasonic Plethysmography (RUP) with simultaneous spirometric measurements in anaesthetized, mechanically ventilated horses.Study designProspective randomized experimental study.AnimalsFive experimental horses.MethodsFive horses were anaesthetized twice (1 week apart) in random order in lateral and in dorsal recumbency. Nine ventilation modes (treatments) were scheduled in random order (each lasting 4 minutes) applying combinations of different tidal volumes (8, 10, 12 mL kg?1) and positive end-expiratory pressures (PEEP) (0, 10, 20 cm H2O). Baseline ventilation mode (tidal volume = 15 mL kg?1, PEEP = 0 cm H2O) was applied for 4 minutes between all treatments. Spirometry and RUP data were downloaded to personal computers. Linear regression analyses (RUP versus spirometric tidal volume) were performed using different subsets of data. Additonally RUP was calibrated against spirometry using a regression equation for all RUP signal values (thoracic, abdominal and combined) with all data collectively and also by an individually determined best regression equation (highest R2) for each experiment (horse versus recumbency) separately. Agreement between methods was assessed with Bland-Altman analyses.ResultsThe highest correlation of RUP and spirometric tidal volume (R2 = 0.81) was found with the combined RUP signal in horses in lateral recumbency and ventilated without PEEP. The bias ± 2 SD was 0 ± 2.66 L when RUP was calibrated for collective data, but decreased to 0 ± 0.87 L when RUP was calibrated with individual data.Conclusions and clinical relevanceA possible use of RUP for tidal volume measurement during IPPV needs individual calibration to obtain limits of agreement within ± 20%.  相似文献   
105.
We used a spatially explicit model of forest dynamics, supported by empirical field data and socioeconomic data, to examine the impacts of human disturbances on a protected forest landscape in Kyrgyzstan. Local use of 27 fruit and nut species was recorded and modeled. Results indicated that in the presence of fuelwood cutting with or without grazing, species of high socioeconomic importance such as Juglans regia, Malus spp., and Armeniaca vulgaris were largely eliminated from the landscape after 50–150 yr. In the absence of disturbance or in the presence of grazing only, decline of these species occurred at a much lower rate, owing to competitive interactions between tree species. This suggests that the current intensity of fuelwood harvesting is not sustainable. Conversely, current grazing intensities were found to have relatively little impact on forest structure and composition, and could potentially play a positive role in supporting regeneration of tree species. These results indicate that both positive and negative impacts on biodiversity can arise from human populations living within a protected area. Potentially, these could be reconciled through the development of participatory approaches to conservation management within this reserve, to ensure the maintenance of its high conservation value while meeting human needs.  相似文献   
106.
Small ruminant lentiviruses infect sheep and goats worldwide, causing chronic progressive diseases and relevant economic losses. Disease eradication and prevention is mostly based on serological testing. The goal of this research was to investigate the presence of the small ruminant lentiviruses (SRLVs) in Jordan and to characterize the serological response in sheep and goat populations. A panel of sera were collected from flocks located in Northern Jordan and Jordan Valley. The samples were tested using three ELISA assays: a commercially available ELISA based on p25 recombinant protein and transmembrane peptide derived from British maedi–visna virus (MVV) EV1 strain, an ELISA based on P16-P25 recombinant protein derived from two Italian strains representative of MVV- and caprine arthritis encephalitis virus (CAEV)-like SRLVs, and an ELISA based on SU5 peptide from the same two Italian isolates. The results indicate that both MVV- and CAEV-like strains are present in Jordan and that the majority of the viruses circulating among sheep and goat populations belong to the MVV-like genotype.  相似文献   
107.
Abstract

A DNA vaccine containing the glycoprotein (G) gene of the North American viral hemorrhagic septicemia virus (VHSV) genotype IVb was developed to evaluate the immune response of fish following vaccination and evaluate its efficacy in protecting a susceptible species, the Muskellunge Esox masquinongy, against VHSV-IVb challenge. Seven weeks (539 degree-days) following vaccination with 10 μg of either pVHSivb-G or a control plasmid, Muskellunge were challenged by immersion with 105 plaque-forming units (pfu)/mL of VHSV-IVb. Fish vaccinated with pVHSivb-G had a relative percent survival (RPS) of 45%. Vaccinated fish also had significantly lower mean viral titers in tissues (4.2 × 102 pfu/g) and viral prevalence (4%) than fish receiving the plasmid control vaccine (3.3 × 105 pfu/g; 82%). Neutralizing antibodies were detected 28 d (308 degree-days) postchallenge (11 weeks postvaccination) in 100% of Muskellunge vaccinated with pVHSivb-G compared with only 12% of plasmid-control-vaccinated Muskellunge, suggesting robust induction of a secondary, adaptive immune response. In addition, pVHSivb-G–vaccinated Rainbow Trout Oncorhynchus mykiss challenged 7 d (100 degree-days) postvaccination with the heterologous novirhabdovirus, infectious hematopoietic necrosis virus (IHNV), experienced an RPS of 61%, compared to control fish, suggesting induction of an early and transient nonspecific antiviral immune response. This study provides an important starting point for VHSV-IVb vaccine development and useful information about the antiviral immune response elicited by DNA vaccination in a nondomesticated fish species.

Received May 1, 2016; accepted September 1, 2016  相似文献   
108.
High fibre breads were produced adding durum wheat bran fractions of different composition and particle size. Fresh products were characterized for texture, crumb grain, volume, colour, water status (water activity, moisture content, frozen water content, 1H molecular mobility).  相似文献   
109.
110.
An in-depth study of the secondary metabolites contained in the Caribbean sponge Smenospongia aurea led to the isolation of smenamide A (1) and B (2), hybrid peptide/polyketide compounds containing a dolapyrrolidinone unit. Their structures were elucidated using high-resolution ESI-MS/MS and homo- and heteronuclear 2D NMR experiments. Structures of smenamides suggested that they are products of the cyanobacterial metabolism, and 16S rRNA metagenomic analysis detected Synechococcus spongiarum as the only cyanobacterium present in S. aurea. Smenamides showed potent cytotoxic activity at nanomolar levels on lung cancer Calu-1 cells, which for compound 1 is exerted through a clear pro-apoptotic mechanism. This makes smenamides promising leads for antitumor drug design.  相似文献   
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