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41.
Valérie Chetboul Cécile Damoiseaux Camille Poissonnier Marie Lavennes Sandrine Bertrand Nicolas Borenstein Luc Behr Jean-Louis Pouchelon Vassiliki Gouni Loïc Desquilbet 《Journal of Veterinary Cardiology》2018,20(6):405-414
Introduction
The objectives of this study were to characterize the epidemiological, clinical, and echocardiographic features of French bulldogs (FBs) with congenital pulmonic stenosis and document their survival times and risk factors for cardiac death (CD).Animals
This study included 66 FBs with congenital pulmonic stenosis.Methods
Prospective cohort study including a survival analysis to assess time to CD.Results
In most cases (53/66, 80%), at least two obstructive lesions were observed, most commonly valvular and supravalvular (42/66, 64%), with pulmonary trunk hypoplasia in 40/66 (61%) of cases. The median Doppler-derived peak trans-stenotic pressure gradient (ΔP) was very high: 170 mmHg (range = 34–291 mmHg), with ΔP ≥ 200 mmHg in 33% of FBs. Among the 51 FBs with an available follow-up and that did not undergo surgical valvuloplasty, 21/51 (41%) died, 67% (14/21) of deaths being CD. The median survival time from diagnosis to CD was 2.8 years (interquartile range = 0.8–4.6 years). Univariate Cox proportional hazard analyses revealed that age (hazard ratio [HR] = 2.3 per 1 year increase; p = 0.02), clinical signs at presentation (HR = 3.7; p = 0.03), ΔP (HR = 1.2 per 10 mmHg increase; p = 0.01), right ventricular dilation (HR = 5.0; p = 0.04), severe tricuspid regurgitation (HR = 7.6; p = 0.001), and right-sided congestive heart failure (HR = 4.8; p = 0.05) were associated with time to CD. After adjustment for age and ΔP, tricuspid regurgitation remained significantly associated with time to CD (HR = 5.1; p = 0.02).Conclusions
Pulmonic stenosis in FBs is commonly severe and complex, with at least 2 obstructive lesions in most cases, a high incidence of pulmonary trunk hypoplasia and CD, and strong association between prognosis and tricuspid regurgitation severity. 相似文献42.
Hibrand-Saint Oyant L Bourges D Chevaleyre C Raze D Locht C Salmon H 《Veterinary research》2005,36(1):63-77
Two Bordetella bronchiseptica mutants, lacking the adenylate cyclase (Cya) or both Cya and pertactin (Prn), were compared with their parental strain NL1013 in their abilities to colonize the nose of neonate piglets and to induce local and systemic antibody responses against filamentous hemagglutinin (FHA) after intranasal (i.n.) inoculation. The number of bacteria recovered and the duration of infection in the nasal secretions were greater for the wild-type parent strain than for the Cya-deficient mutant, indicating that Cya plays an important role during B. bronchiseptica colonization of the nasal cavity. The double mutant did not colonize the nasal cavity and was less able to adhere to epithelial cells in vitro than the other two strains, supporting the hypothesis that Prn plays a major role in cell adhesion. In piglets inoculated with the wild type strain, anti-FHA IgM was found in the nasal secretions one week after inoculation, followed two weeks later by anti-FHA IgA; their presence was concomitant with decreases in bacterial counts. Anti-FHA IgG appeared at six weeks after infection in the serum. In contrast, i.n. inoculation with either mutant failed to induce a nasal secretory antibody response but did induce an earlier and higher IgM response in the serum than inoculation with the wild type strain. However, only the Cya-deficient mutant was able to prime the piglets for the development of a secondary nasal IgM and serum IgG response to FHA after intranasal inoculation with the wild type B. bronchiseptica. 相似文献
43.
Mechanisms of metal-phosphates formation in the rhizosphere soils of pea and tomato: environmental and sanitary consequences 总被引:1,自引:0,他引:1
Annabelle Austruy Muhammad Shahid Tiantian Xiong Maryse Castrec Virginie Payre Nabeel Khan Niazi Muhammad Sabir Camille Dumat 《Journal of Soils and Sediments》2014,14(4):666-678
Purpose
At the global scale, soil contamination with persistent metals such as lead (Pb), zinc (Zn), and copper (Cu) induces a serious threat of entering the human food chain. In the recent past, different natural and synthetic compounds have been used to immobilize metals in soil environments. However, the mechanisms involved in amendment-induced immobilization of metals in soil remained unclear. The objective of the present work was therefore to determine the mechanisms involved in metal-phosphates formation in the rhizospheric soils of pea and tomato currently cultivated in kitchen gardens.Materials and methods
Pea and tomato were cultivated on a soil polluted by past industrial activities with Pb and Zn under two kinds of phosphate (P) amendments: (1) solid hydroxyapatite and (2) KH2PO4. The nature and quantities of metal-P formed in the rhizospheric soils were studied by using the selective chemical extractions and employing the combination of X-ray fluorescence micro-spectroscopy, scanning electron microscopy, and electron microprobe methods. Moreover, the influence of soil pH and organic acids excreted by plant roots on metal-P complexes formation was studied.Results and discussion
Our results demonstrated that P amendments have no effect on metal-P complex formation in the absence of plants. But, in the presence of plants, P amendments cause Pb and Zn immobilization by forming metal-P complexes. Higher amounts of metal-P were formed in the pea rhizosphere compared to the tomato rhizosphere and in the case of soluble P compared to the solid amendment. The increase in soil-metal contact time enhanced metal-P formation.Conclusions
The different forms of metal-P formed for the different plants under two kinds of P amendments indicate that several mechanisms are involved in metal immobilization. Metal-P complex formation in the contaminated soil depends on the type of P amendment added, duration of soil-plant contact, type of plant species, and excretion of organic acids by the plant roots in the rhizosphere. 相似文献44.
Gancel AL Ollitrault P Froelicher Y Tomi F Jacquemond C Luro F Brillouet JM 《Journal of agricultural and food chemistry》2003,51(20):6006-6013
Volatile compounds were extracted by a pentane/ether (1:1) mixture from the leaves of seven citrus somatic tetraploid hybrids sharing mandarin as their common parent and having lime, Eurêka lemon, lac lemon, sweet orange, grapefruit, kumquat, or poncirus as the other parent. Extracts were examined by GC-MS and compared with those of their respective parents. All hybrids were like their mandarin parent, and unlike their nonmandarin parents, in being unable to synthesize monoterpene aldehydes and alcohols. The hybrids did retain the ability, although strongly reduced, of their nonmandarin parents to synthesize sesquiterpene hydrocarbons, alcohols, and aldehydes. These results suggest that complex forms of dominance in the mandarin genome determine the biosynthesis pathways of volatile compounds in tetraploid hybrids. A down-regulation of the biosynthesis of methyl N-methylanthranilate, a mandarin-specific compound, originates from the genomes of the nonmandarin parents. Statistical analyses showed that all of the hybrids were similar to their common mandarin parent in the relative composition of their volatile compounds. 相似文献
45.
Release of deuterated (E)-2-nonenal during beer aging from labeled precursors synthesized before boiling 总被引:1,自引:0,他引:1
Liégeois C Meurens N Badot C Collin S 《Journal of agricultural and food chemistry》2002,50(26):7634-7638
Although lipid autoxidation in the boiling kettle is a key determinant of the cardboard flavor of aged beers, recent results show that mashing is another significant source of wort nonenal potential, the well-known indicator of how a beer will release (E)-2-nonenal during storage. Although unstable, deuterated (E)-2-nonenal nitrogen adducts created during mashing can in some cases partially persist in the pitching wort, to release deuterated (E)-2-nonenal during beer aging. In the experiment described here, the relative contributions of mashing and boiling were estimated at 30 and 70%, respectively. The presence of oxygen during mashing and, to a lesser extent, high lipoxygenase activity can intensify the stale cardboard flavor. 相似文献
46.
Pezet R Perret C Jean-Denis JB Tabacchi R Gindro K Viret O 《Journal of agricultural and food chemistry》2003,51(18):5488-5492
Delta-viniferin is a resveratrol dehydrodimer, an isomer of epsilon-viniferin. This compound has been reported as a molecule produced in vitro by the oxidative dimerization of resveratrol by plant peroxidases or fungal laccases. It was also recently identified in wines and in grape cell cultures. We have now identified this dimer by NMR, high-performance liquid chromatography-diode array detection (HPLC-DAD), and HPLC-mass spectrometry (MS) in grapevine leaves infected by Plasmopara viticola (downy mildew) or UV-C irradiated. Its concentration was higher than that of epsilon-viniferin and constitutes one of the most important phytoalexins derived from resveratrol. 相似文献
47.
Camille C. Hanot Katrina L. Mealey Janean L. Fidel Neal S. Burke Laura A. White Rance K. Sellon 《Journal of veterinary pharmacology and therapeutics》2020,43(2):231-236
Prednisone resistance develops rapidly and essentially universally when dogs with lymphoma are treated with corticosteroids. We investigated naturally occurring mechanisms of prednisone resistance in seven dogs with naïve multicentric lymphoma, treated with oral prednisone; four dogs were administered concurrent cytotoxic chemotherapy. Expression of NR3C1α, ABCB1 (formerly MDR1), 11β-HSD1, and 11β-HSD2 mRNA was evaluated in neoplastic lymph nodes by real-time RT-PCR. Changes of expression levels at diagnosis and at time of clinical resistance to prednisone were compared longitudinally using a Wilcoxon signed-rank test. Clinical resistance to prednisone was observed after a median of 68 days (range: 7–348 days) after initiation of treatment. Relative to pretreatment samples, prednisone resistance was associated with decreased NR3C1α expression in biopsies of all dogs with high-grade lymphoma (six dogs, p=.031); one dog with indolent T-zone lymphoma had increased expression of NR3C1α. Resistance was not consistently associated with changes in ABCB1, 11β-HSD1, or 11β-HSD2 expression. Decreased expression of the glucocorticoid receptor (NR3C1α) may play a role in conferring resistance to prednisone in dogs with lymphoma. Results do not indicate a broad role for changes in expression of ABCB1, 11β-HSD1, and 11β-HSD2 in the emergence of prednisone resistance in lymphoma-bearing dogs. 相似文献
48.
Burrows MT Schoeman DS Buckley LB Moore P Poloczanska ES Brander KM Brown C Bruno JF Duarte CM Halpern BS Holding J Kappel CV Kiessling W O'Connor MI Pandolfi JM Parmesan C Schwing FB Sydeman WJ Richardson AJ 《Science (New York, N.Y.)》2011,334(6056):652-655
Climate change challenges organisms to adapt or move to track changes in environments in space and time. We used two measures of thermal shifts from analyses of global temperatures over the past 50 years to describe the pace of climate change that species should track: the velocity of climate change (geographic shifts of isotherms over time) and the shift in seasonal timing of temperatures. Both measures are higher in the ocean than on land at some latitudes, despite slower ocean warming. These indices give a complex mosaic of predicted range shifts and phenology changes that deviate from simple poleward migration and earlier springs or later falls. They also emphasize potential conservation concerns, because areas of high marine biodiversity often have greater velocities of climate change and seasonal shifts. 相似文献
49.
50.
The developmentally arrested infective larva of hookworms encounters a host-specific signal during invasion that initiates the resumption of suspended developmental pathways. The resumption of development during infection is analogous to recovery from the facultative arrested dauer stage in the free-living nematode Caenorhabditis elegans. Infective larvae of the canine hookworm Ancylostoma caninum resume feeding and secrete molecules important for infection when exposed to a host mimicking signal in vitro. This activation process is a model for the initial steps of the infective process. Dauer recovery requires protein synthesis, but not RNA synthesis in C. elegans. To determine the role of RNA and protein synthesis in hookworm infection, inhibitors of RNA and protein synthesis were tested for their effect on feeding and secretion by A. caninum infective larvae. The RNA synthesis inhibitors α-amanitin and actinomycin D inhibit feeding dose-dependently, with IC(50) values of 30 and 8 μM, respectively. The protein synthesis inhibitors puromycin (IC(50)=110 μM), cycloheximide (IC(50)=50 μM), and anisomycin (IC(50)=200 μM) also displayed dose-dependent inhibition of larval feeding. Significant inhibition of feeding by α-amanitin and anisomycin occurred when the inhibitors were added before 12h of the activation process, but not if the inhibitors were added after 12h. None of the RNA or protein synthesis inhibitors prevented secretion of the activation-associated protein ASP-1, despite nearly complete inhibition of feeding. The results indicate that unlike dauer recovery in C. elegans, de novo gene expression is required for hookworm larval activation, and the critical genes are expressed within 12h of exposure to activating stimuli. However, secretion of infection-associated proteins is independent of gene expression, indicating that the proteins are pre-synthesized and stored for rapid release during the initial stages of infection. The genes that are inhibited represent a subset of those required for the transition to parasitism, and therefore represent interesting targets for further investigation. Furthermore, while dauer recovery provides a useful model for hookworm infection, the differences identified here highlight the importance of exercising caution before making generalizations about parasitic nematodes based on C. elegans biology. 相似文献