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921.
Halima Benbouza George Lognay Jodi Scheffler Jean Pierre Baudoin Guy Mergeai 《Euphytica》2009,165(2):211-221
The expression of the “glanded-plant and glandless-seed” trait was assessed using High Performance Liquid Chromatography (HPLC) analysis methods in different Gossypium hybrids obtained by crossing Australian diploid cottons and various diploid and tetraploid species. Significant variation
in the gossypol content in the seed was observed among the analyzed genotypes. HPLC data demonstrated that the gossypol synthesis
repression mechanism in the Australian diploid species belonging to C and G genomes was dominant but did not confirm its preferential
functioning against A genome species bearing GL2 locus. About 10% of the produced seeds had total gossypol content lower than the limit imposed by the World Health Organisation
(600 ppm) for the use of cotton flour in food and feed. HPLC analysis of the terpenoids aldehyde (TA) contents in the aerial
parts of the hybrids showed important qualitative and quantitative variability. This result could indicate a certain separation
between pigment gland morphogenesis and terpenoid synthesis mechanisms in cotton. 相似文献
922.
Bohler S Sergeant K Lefèvre I Jolivet Y Hoffmann L Renaut J Dizengremel P Hausman JF 《Tree physiology》2010,30(11):1415-1432
Populus tremula L. × Populus alba L. (Populus ×c anescens (Aiton) Smith) - clone INRA 717-1-B4 saplings (50 cm apex to base and carrying 19 leaves on average) - were followed for 28 days. Half of the trees were grown in charcoal-filtered air while the other half were exposed to 120 ppb ozone for 11 h a day during the light period. The expanding leaf number 4 was tagged at the beginning of the experiment and finished expansion between 7 and 14 days. These leaves were harvested weekly for biochemical and proteome analyses using quantitative bidimensional electrophoresis (DiGE). Independent of the ozone treatment, all the analyses allowed a distinction between expanding and adult leaves. The results indicate that during the expansion phase (Days 0-7) the enzymatic machinery of the leaves is set up, and remains dynamically stable in the adult leaves (Days 14-28). Although ozone had no apparent effect on expanding leaves, the metabolic stability in fully expanded leaves observed in ozone-free plants was disturbed after 2 weeks of exposure and a stress-induced response became apparent. 相似文献
923.
Eve Ramery Laurence Fievez Audrey Fraipont Fabrice Bureau Pierre Lekeux 《Veterinary research》2010,41(2)
The long pentraxin 3 (PTX3) plays an important role in host defence and its over-expression may contribute to airway injury. The aim of the present study was therefore to characterize in more detail PTX3 and its expression in the horses’ airway. Six healthy horses and six horses affected by recurrent airway obstruction (R.A.O.) were submitted to a dusty environment challenge. PTX3 DNA and cDNA were cloned and sequenced. PTX3 expression was evaluated by RT-qPCR, Western blotting and immuno-histochemistry in bronchoalveolar lavage fluid (BALF) cells, BALF supernatant and bronchial epithelial cells. An alternative splicing of the second exon of PTX3 occurred, resulting in two forms of the protein: “spliced” (32 kDa) and “full length” (42 kDa). PTX3 was detected in BALF macrophages, neutrophils and bronchial epithelial cells. It was over-expressed in the BALF supernatant from R.A.O.-affected horses in crisis. However, dust was unable to induce PTX3 in BALF cells ex vivo, indicating that dust is an indirect inducer of PTX3. Dust exposure in-vivo induced PTX3 in BALF macrophages but there was no significant difference between healthy and R.A.O.-affected horses. Conversely, PTX3 was over-expressed in the bronchial epithelial cells from R.A.O.-affected horses in crisis. These data indicate a differential regulatory mechanism in inflammatory and bronchial epithelial cells and offer therapeutically interesting perspectives. 相似文献
924.
ABSTRACT The identification and detection of Pseudomonas syringae pv. papulans, the causal agent of blister spot of apple, on apple leaves and fruit was achieved by polymerase chain reaction amplification of a specific DNA fragment of the hrpL sequence. The consensus primers hrpL(1) and hrpL(2) were designed based on the alignment of pseudomonad hrpL gene sequences available in nucleic acid data banks. This primer set produced a 631-bp amplicon from 37 of the 57 pseudomonads strains tested. These strains belonged to genomospecies 1 and 2, as described by Gardan et al. (8). The amplicon obtained from 30 of these strains was digested with eight restriction enzymes. Three different restriction patterns were produced from strains belonging to genomospecies 1, resulting in A1 and A2 patterns, while strains belonging to genomospecies 2 were characterized by a B pattern. Patterns A1 and A2 differed at only two sites, a Bsp 143I site located at nucleotide 360 and a MseI site located at nucleotides 22-24. Group A2 consisted solely of P. syringae pv. papulans strains. The hrpL gene in P. syringae pv. papulans strain CFBP3323 was sequenced. Two primer sets, Pap1/Pap2 and Pap1/Pap3, were designed and tested for specificity to P. syringae pv. papulans. These primers amplified expected fragments of 242 and 303 bp, respectively. Pap1/Pap2 amplified a fragment only with P. syringae pv. papulans DNA, while Pap1/Pap3 amplified all tested strains belonging to genomospecies 1. A diagnostic procedure using the Pap1/Pap2 primer set was successful for the detection of P. syringae pv. papulans in diseased fruit and artificially inoculated leaves. 相似文献
925.
A peptide vaccine administered transcutaneously together with cholera toxin elicits potent neutralising anti-FMDV antibody responses 总被引:2,自引:0,他引:2
Beignon AS Brown F Eftekhari P Kramer E Briand JP Muller S Partidos CD 《Veterinary immunology and immunopathology》2005,104(3-4):273-280
In this study a synthetic peptide representing residues 141-159 from the GH loop of VP1 protein of foot-and-mouth disease virus was tested for its capacity to elicit virus neutralising antibodies in mice after transcutaneous immunisation. Topical application of the peptide conjugated to bovine serum albumin together with cholera toxin as an adjuvant elicited anti-peptide antibody responses with strong virus neutralising activity. The combination of cholera toxin with an immunostimulatory CpG motif resulted in the induction of IgG1 and IgG2a anti-peptide antibodies with significantly enhanced virus neutralising activity. To shed more light on the mechanisms of cholera toxin adjuvanticity we demonstrated its binding to keratinocytes via GM(1)-gangliosides. This was followed by an increase of the intracellular cAMP and the rapid diffusion of cholera toxin throughout the epidermis. These findings demonstrate that peptide-based vaccines when combined with the appropriate adjuvant(s) can elicit potent virus neutralising antibody responses after transcutaneous immunisation. However, experiments in target species will be required to confirm the potential of this simple vaccination procedure in livestock. 相似文献
926.
Boda C Enanga B Dumet H Chauviere G Labrousse F Couquet C Saivin S Houin G Perie J Dumas M Bouteille B 《Veterinary parasitology》2004,121(3-4):213-223
Experimentally infected sheep have been previously developed as an animal model of trypanosomosis. We used this model to test the efficacy of megazol on eleven Trypanosoma brucei brucei-infected sheep. When parasites were found in blood on day 11 post-infection, megazol was orally administered at a single dose of 40 or 80mg/kg. After a transient aparasitaemic period, all animals except two relapsed starting at day 2 post-treatment, which were considerated as cured on day 150 post-treatment and showed no relapse after a follow-up period of 270 days. In order to understand the high failure of megazol treatment to cure animals, a kinetic study was carried out. Plasma concentrations of megazol determined, by reverse-phase high-performance liquid chromatography at 8h post-treatment in these animals, were lowered, suggesting slow megazol absorption, except in cured animals. However, megazol plasma profiles in uninfected sheep after a single oral dose of megazol showed a fast megazol lowered absorption associated with a short plasma half-life of drug. Inter-individual variation of megazol pharmacokinetic properties was also observed. These findings suggested that the high failure rates of megazol treatment were related to poor drug availability after oral administration in sheep. In conclusion, megazol could cure sheep with T. b. brucei infection but oral administration was not an effective route. 相似文献
927.
Kirsten Gnirs DVM Yannick Ruel DVM Stephane Blot DVM PHD Dominique Begon DVM Delphine Rault DVM Franloise Delisle DVM Lilia Boulouha DVM Marie-anne Colle DVM Claude Carozzo DVM Pierre Moissonnier DVM PHD 《Veterinary radiology & ultrasound》2003,44(4):402-408
Thirteen dogs, including 6 Rottweiler dogs, exhibiting clinical signs of spinal cord dysfunction and myelographically confirmed subarachnoid space enlargement were investigated. To characterize the lesions and to get a better understanding of their pathogenesis, different imaging techniques were used in association with explorative surgical procedures (12 dogs) and histopathologic techniques (5 dogs). All subjects underwent preoperative myelography, five of which were examined by computed tomography (CT) scanning and one by magnetic resonance imaging (MRI) as well as cerebrospinal fluid (CSF) flow measurement (velocimetry). Most animals were <12 months old (7/13 dogs) and Rottweilers were over-represented (6/13 dogs). The lesions were mainly located dorsally with respect to the spinal cord (10/13 dogs) and in the cranial cervical area (8/13 dogs). MRI suggested spinal cord deviation with signs of ventral leptomeningeal adhesion opposite the enlarged space. In one dog, velocimetry confirmed that the "cyst" was freely communicating with the surrounding CSF space. Surgical investigation confirmed leptomeninges-induced ventral adhesion in 4/5 dogs. Follow-up studies, carried out from 6 months to 2.5 years postoperatively, showed there was full recovery in 8/13 dogs. This study suggests that the compression of the spinal cord is possibly not caused by a cyst. Adhesion resulting from a combination of microtrauma and chronic inflammatory processes induces a secondary enlargement of the subarachnoid space and may be a significant causative factor in spinal cord compression and dysfunction. The over-representation of Rottweilers and the young age of the animals in the study suggest a possible genetic predisposition and an inherited etiology. 相似文献
928.
OBJECTIVE: To report the use of dorsal acetabular augmentation (DAA) in canine total hip arthroplasty (THA) and to evaluate the clinical and radiographic outcome after a minimum of 1 year follow-up. STUDY DESIGN: Clinical study. ANIMALS: Nine dogs that had THA. METHODS: Ten hips requiring acetabular augmentation for optimum acetabular cup implantation for THA were evaluated retrospectively. The excised femoral head and neck was used as the corticocancellous bone graft for index THA surgeries, and the dorsal crest of the ipsilateral ilial wing was used as the bone graft in 1 dog that had a revision surgery. Clinical and radiographic follow-up examinations were performed at approximately 8 weeks and 1 year postoperatively. Long-term radiographic examinations included use of a standing dorsal acetabular rim (DAR) projection for assessment of graft-recipient boundary. Functional clinical outcome was assessed using direct patient evaluation and telephone interview. RESULTS: One dog failed to regain limb function after surgery. Suspected aseptic loosening of the acetabular cup was observed on radiographs approximately 12 weeks postoperatively. Excluding this single explantation, follow-up physical and radiographic examinations indicated good implant and graft positioning and normal function for all dogs. CONCLUSIONS: Acetabular augmentation permitted implantation of an appropriately sized acetabular cup while maintaining complete DAR coverage of the prosthesis. Nine out of 10 hips had a successful outcome with minimal radiographic and no functional abnormalities. Further follow-up is necessary to determine the long-term outcome of DAR augmentation in canine THA. CLINICAL RELEVANCE: Acetabular augmentation with an autogenous corticocancellous bone graft constructed from the femoral head and neck can provide complete DAR coverage to permit use of an appropriately sized acetabular cup in THA. 相似文献
929.
Diarra MS Petitclerc D Deschênes E Lessard N Grondin G Talbot BG Lacasse P 《Veterinary immunology and immunopathology》2003,95(1-2):33-42
Antibiotics should combine good antibacterial activity and the capacity to work in association with the host defence system. In this study, we have investigated the effects of bovine lactoferrin alone or in combination with penicillin G on the phagocytic activity of bovine polymorphonuclear leukocytes against Staphylococcus aureus. We have shown that susceptibility of S. aureus to phagocytosis was decreased in the presence of penicillin in the medium. In a kinetic study, lactoferrin alone did not affect phagocytosis but, when used with penicillin, it reversed the negative effect of this antibiotic on phagocytosis. In addition, in an epithelial invasion assay, lactoferrin alone or in combination with penicillin reduced the invasion of mammary epithelial cells in culture by S. aureus. Lactating female CD-1 mice were infected by intra-mammary delivery of a virulent penicillin-susceptible S. aureus strain and were then randomly assigned to treatments according to a 2 x 2 factorial design. In this mouse mastitis model, 2 days of systemic treatments with lactoferrin and/or penicillin did not lead to a total clearance of infection by S. aureus, but bacterial number was significantly reduced by treatments with lactoferrin or penicillin. These data suggest that bovine lactoferrin, alone or in combination with penicillin G, enhances S. aureus susceptibility to immuno-defense mechanisms, which can be beneficial in the treatment of S. aureus infections. 相似文献
930.
van Erck E Votion DM Kirschvink N Art T Lekeux P 《American journal of veterinary research》2003,64(11):1414-1420
OBJECTIVE: To compare sensitivity of the impulse oscillometry system (IOS) with that of the conventional reference technique (CRT; ie, esophageal balloon method) for pulmonary function testing in horses. ANIMALS: 10 horses (4 healthy; 6 with recurrent airway obstruction [heaves] in remission). PROCEDURE: Healthy horses (group-A horses) and heaves-affected horses (group-B horses) were housed in a controlled environment. At each step of a methacholine bronchoprovocation test, threshold concentration (TC(2SD); results in a 2-fold increase in SD of a value) and sensitivity index (SI) were determined for respiratory tract system resistance (R(rs)) and respiratory tract system reactance (X(rs)) at 5 to 20 Hz by use of IOS and for total pulmonary resistance (RL) and dynamic lung compliance (C(dyn)), by use of CRT. RESULTS: Bronchoconstriction resulted in an increase in R(rs) at 5 Hz (R(5Hz)) and a decrease in X(rs) at all frequencies. Most sensitive parameters were X(rs) at 5 Hz (X(5Hz)), R(5Hz), and R(5Hz):R(10Hz) ratio; RL and the provocation concentration of methacholine resulting in a 35% decrease in dynamic compliance (PC(35)C(dyn)) were significantly less sensitive than these IOS parameters. The TC(2SD) for X(rs) at 5 and 10 Hz was significantly lower in group-B horses, compared with group-A horses. The lowest TC(2SD) was obtained for X(5Hz) in group-B horses and R(5Hz) in group-A horses. CONCLUSIONS AND CLINICAL RELEVANCE: In contrast to CRT parameters, IOS parameters were significantly more sensitive for testing pulmonary function.The IOS provides a practical and noninvasive pulmonary function test that may be useful in assessing subclinical changes in horses. 相似文献