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121.
At 15 days of age and in the presence of measurable levels of maternal antibody against infectious bursal disease virus serotype I (1:170 virus-neutralization geometric mean titer), a recent isolate (U-28) and a prototype virulent isolate (Edgar) of the same virus caused subclinical infections in commercial broiler chickens. Isolate U-28 caused a significant reduction in the size of the bursa of Fabricius, whereas the Edgar isolate produced splenomegaly. Both isolates reduced the serological response to Newcastle disease virus. The experimental immunosuppressive potential and pathogenicity of isolate U-28 in broiler chickens confirms the role of this virus in recent infectious bursal disease outbreaks. 相似文献
122.
Conxita Royo Marco Maccaferri Fanny Álvaro Marc Moragues Maria Corinna Sanguineti Roberto Tuberosa Fouad Maalouf Luis F. García del Moral Andrea Demontis Sayar Rhouma Miloudi Nachit Nasserlehaq Nserallah Dolors Villegas 《Field Crops Research》2010
A collection of 191 durum wheat accessions representing Mediterranean Basin genetic diversity was grown in nine different environments in four countries, with productivities ranging from 0.99 to 6.78 t ha−1. The population breeding structure comprised eight genetic subpopulations (GSPs) using data derived from 97 evenly distributed SSR markers. The phenotypic structure was assessed: (i) from the mean values of six agronomic traits across environments (multivariate), and (ii) from data representing each trait in each environment (univariate). Mean daily maximum temperature from emergence to heading was significantly (P < 0.05) and negatively associated to yield, accounting for 59% of yield variations. Significant but weak relationships were obtained between the genetic similarities among accessions and their overall agronomic performance (r = 0.15, P < 0.001), plant height (r = 0.12, P < 0.001), spike–peduncle length (r = 0.06, P < 0.01) and thousand kernel weight (r = 0.03, P < 0.05), suggesting a very low possibility of prediction of the agronomic performance based on random SSR markers. The percentage of variability (measured by sum of squares) explained by the environment varied between 76.3 and 98.5% depending on the trait, while that explained by genotypes ranged between 0.4 and 12.6%, and that explained by the GE interaction ranged from 1.1 to 12.5%. The clustering of the accessions based on multivariate phenotypic data offered the best explanation of genotypic differences, accounting for 30.3% (for yield) to 75.1% (for kernel weight) of the observed variation. The genotype × environment interaction was best explained by the phenotypic univariate clustering procedure, which explained from 28.5% (for kernel weight) to 74.9% (for days to heading) of variation. The only accessions that clustered both in the genetic dissimilarities tree and the tree obtained using Euclidean distances based on standardized phenotypic data across environments were those closely related to the CIMMYT hallmark founder ‘Altar 84’, the ICARDA accessions adapted to continental-dryland areas, and the landraces, suggesting that genetic proximity corresponded to agronomic performance in only a few cases. 相似文献
123.
Marta León Belén Rosado Sylvia García-Belenguer Gema Chacón Ainara Villegas Jorge Palacio 《Journal of Veterinary Behavior: Clinical Applications and Research》2012,7(6):348-352
Canine aggression is the most common reason for the referral of dogs to behavior practices. In addition, dog bites represent an important problem for public health and animal welfare. The serotonergic system is believed to play an important role in modulating aggression. The aim of the present study was (1) to assess the suitability of different types of blood samples for measuring circulating serotonin in canine clinical studies, and (2) to investigate the relationship between the serotonergic system and canine aggression. The assessment of serotonin was simultaneously carried out in serum, plasma, and platelets of 28 aggressive and 10 nonaggressive dogs with an enzyme immunoassay technique. The mean serotonin concentration in aggressive dogs was significantly lower than in nonaggressive dogs in all the assayed samples. These findings suggest an inverse relationship between the activity of the serotonergic system and canine aggression. Considering the simplicity of the methodology, the authors propose sampling serum as the most suitable method for measuring circulating serotonin in dogs. 相似文献
124.
Recombinant avian adeno-associated viruses coding for the LacZ gene were used to inoculate embryonating chicken eggs, to assess the usefulness of the system for the expression of a transgene in vivo. The results obtained indicate significantly higher levels of expression of the reporter gene at various time intervals in the embryos inoculated with the recombinant virus in comparison with the mock-inoculated controls. At the embryo level, significant differences were evident at 120 hr postinoculation; hatched chicks showed transgene expression up to 14 days of age. In a second experiment, different cell-line cultures were transfected with plasmids encoding for a reporter gene flanked by the avian adeno-associated virus inverted terminal repeats (ITR), either alone or in the presence of the major nonstructural proteins of the virus (Rep 78/68) to assess the ability of these proteins and DNA elements to enhance gene expression. Results indicate that the inclusion of the viral ITR alone or during coexpression of the Rep proteins significantly enhances the expression of the transgene in all cell lines tested, as evidenced by the detection of the beta-galacrosidase protein through chemiluminescence reactions and staining of transfected monolayers. 相似文献
125.
Cyclosporin A (CsA) is an immunosuppressive agent that can be used as alternative treatment to glucocorticoid therapy. This case report describes a case of vesicular cutaneous lupus erythematosus in a rough collie successfully controlled with oral CsA for more than 18 months. 相似文献
126.
Fourier transform (FT) Raman spectroscopy was used to elucidate heat-induced structural changes of albumin, globulins, serum, and plasma protein solutions (15% w/w) as affected by pH (4.5, 6.0, and 7.5). Reduction of alpha-helix and formation of beta-sheet, disulfide bond reactions, and exposure and buriedness of hydrophobic groups and amino acid residues were observed. All of these features contributed to the formation of strong, irreversible heat-induced gels. The application of a dimensionality reducing technique such as principal component analysis proved to be useful to determine the most influential qualities of protein samples, as well as the pH-dependent behavior of some of the attributes of both unheated and heated solutions. Analysis of Raman spectra in terms of differences demonstrated the interactions of albumin and globulins in co-occurrence and the significant role of fibrinogen on the gel's attributes. 相似文献
127.
128.
Docampo MJ Zanna G Fondevila D Cabrera J López-Iglesias C Carvalho A Cerrato S Ferrer L Bassols A 《Veterinary dermatology》2011,22(6):535-545
The Chinese shar-pei dog is known for its distinctive feature of wrinkled and thickened skin, defined as primary or hereditary cutaneous mucinosis. In a recent report, we identified the mucinous material deposited in the shar-pei skin as the polysaccharide hyaluronan (HA). In the present work, the molecular and cellular mechanisms underlying this phenotype have been identified in dermal fibroblasts isolated from shar-pei dogs. The production of HA, which appeared to be mainly associated with cell membrane protrusions and also intracellular, was higher in shar-pei fibroblasts than in control cells. The HA accumulation is related to a higher mRNA expression of the isoform HAS2 of the HA-synthesizing enzyme family, hyaluronan synthases (HAS). The higher expression of HAS2 in shar-pei fibroblasts was confirmed at the protein level. The other HAS isoenzymes, HAS1 and HAS3, and the HA-degrading enzymes, Hyal1 and Hyal2, were not differentially expressed in shar-pei fibroblasts compared with cells from control dogs. Fibroblasts from shar-pei dogs and from control dogs are morphologically different as observed by transmission electron microscopy. Scanning electron microscopy revealed a large number of cellular protrusions with associated globular deposits. Electron microscopy after labelling with biotinylated HA-binding protein confirmed an increased HA content in shar-pei fibroblasts, which could be localized in several subcellular structures. The authors propose the name hereditary cutaneous hyaluronosis (HCH) for affected dogs, because it better defines the cutaneous mucinosis of shar-pei dogs. 相似文献
129.
We report the first successful production of PRSV-P resistant backcross (BC) papaya plants following intergeneric hybridisation
between C. papaya and a Vasconcellea species after 50 years of reports on unsuccessful attempts. This follows our previous reports of PRSV-P resistant F1 hybrids developed by intergeneric hybridisation between C. papaya and V. quercifolia. One PRSV-P resistant BC 1 (BC1) plant was produced after 114,839 seeds were dissected from 940 fruits. The seeds yielded 1,011 embryos and 733 germinated
in vitro from which 700 developed into plantlets that were screened in a glasshouse and in the field under high disease pressure
and exposure to inoculation by viruliferous aphids. From the PRSV-P resistant backcross 1 (BC1) male plant, 1465 plants [137 BC2, 546 SbC2 (BC2 sib-crosses), 147 BC3, 379 SbC3 and 256 BC4] were grown from seed and inoculated with PRSV-P and virus resistant BC3 and BC4 plants were selected from these generations. Presence or absence of virus was confirmed by ELISA serological tests. BC plants
generally developed mild symptoms of PRSV-P after periods ranging from 5 to 18 months in the field but many showed the ability
to produce new growth free of symptoms. All control plants developed severe symptoms after 3 months in the field. Some BC3 and BC4 plants were free from viral infection after 18 months in the field. Subsequently they developed very mild symptoms on their
leaves and a few ringspots on their fruit. They continued to grow vigorously and produce fruit for 3 years under high disease
pressure provided by the infected controls and other susceptible plants. Good quality marketable fruit were produced on these
plants. Application of these results should lead to restoration of the papaya industry in virus-infested regions of the Philippines
and worldwide. 相似文献
130.
The avian adeno-associated virus (AAAV) is a replication-defective nonpathogenic virus member of the family Parvoviridae that has been proved to be useful as a viral vector for gene delivery. The use of AAAV for transgenic expression of Newcastle disease virus (NDV) hemagglutinin-neuraminidase (HN) protein and its ability to induce immunity in chickens were assessed. Proposed advantages of this system include no interference with maternal antibodies, diminished immune response against the vector, and the ability to accommodate large fragments of genetic information. In this work the generation of recombinant AAAV virions expressing the HN protein (rAAAV-HN) was demonstrated by electron microscopy, immunocytochemistry, and western blot analysis. Serological evidence of HN protein expression after in ovo or intramuscular inoculation of the recombinant virus in specific-pathogen-free chickens was obtained. Serum from rAAAV-HN-vaccinated birds showed a systemic immune response evidenced by NDV-specific enzyme-linked immunosorbent assay and hemagglutination inhibition testing. Positive virus neutralization in embryonated chicken eggs and indirect immunofluorescence detection of NDV infected cells by serum from rAAAV-HN vaccinated birds is also reported. A vaccine-challenge experiment in commercial broiler chickens using a Venezuelan virulent viscerotropic strain of NDV was performed. All unvaccinated controls died within 5 days postchallenge. Protection up to 80% was observed in birds vaccinated in ovo and revaccinated at 7 days of age with the rAAAV-HN. The results demonstrate the feasibility of developing and using an AAAV-based gene delivery system for poultry vaccination. 相似文献