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151.
When warmer means weaker: high temperatures reduce behavioural and immune defences of the larvae of a major grapevine pest 总被引:1,自引:0,他引:1
Corentin Iltis Guillaume Martel Denis Thiéry Jérôme Moreau Philippe Louâpre 《Journal of pest science》2018,91(4):1315-1326
Phytophagous insects evolving in agroecosystems express numerous defences when faced with myriads of natural enemies. Such defensive traits might impair the effectiveness of biological control relying on these natural enemies, mostly parasitoids. In the case of parasitoid threat, these defences consist of the avoidance of the parasitoid (reduced exposure to antagonists through shortening of developmental time), hindrance of oviposition (evasive behaviours and morphological protection) or destruction of the parasitoid eggs (encapsulation and melanisation by means of the immune system). Previous works focused on one defensive trait only when investigating the effects of temperature on host resistance. By doing so, they assumed that all defensive traits would respond uniformly to a change occurring in thermal environment, which remains an undocumented fact. To test this assumption in the context of global warming, we adopted a global overview of host resistance by examining the effects of rising temperatures on multiple defensive traits used by the grape pest, Lobesia botrana, against its larval parasitoids. Although warmer conditions led to reduced exposure to parasitoids by accelerating larval development, warmer conditions also elicited extensive weakening of behavioural and immune defences. These results confirm that temperatures might differently modulate the levels of expression of several defensive traits. An increase in growth rate and pupal mass also occurred, especially for females, which may contribute to greater pest fecundity in the future. However, the decline of L. botrana resistance might enhance the efficiency of the biological control naturally exerted by parasitoids in vineyards, thereby limiting the damage to crops. 相似文献
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153.
Amélie Choquette Jérôme R.E. del Castillo Maxim Moreau Martin Guillot Kate Alexander Jean-Jacques Kona-Boun Dominique Gauvin Eric Troncy 《Veterinary anaesthesia and analgesia》2017,44(2):317-328
Objective
To compare the motor and sensory block efficacy and duration of a modified paravertebral brachial plexus block (PBPB) after administration of lidocaine alone (LI) or combined with epinephrine (LE).Study design
Prospective, randomized, blinded, crossover study.Animals
A total of eight healthy female Beagle dogs.Methods
Under general anesthesia, modified PBPB was performed on the left thoracic limb using neurostimulation and/or ultrasound guidance to administer lidocaine (2 mg kg–1; 0.2 mL kg–1) either alone (treatment LI, n = 10) or with epinephrine (1:100,000; treatment LE, n = 9). Sensory block was evaluated through reaction to a painful mechanical stimulus applied at five sites on the limb. Motor block effect was evaluated according to visual gait assessments and thoracic limb vertical force measurements under dynamic and static conditions. Data were analyzed using repeated-measures generalized estimating equations. All statistical tests were performed two-sided at the α = 0.05 significance threshold.Results
The duration of sensory block did not differ significantly between treatments. Visible gait impairment was more persistent in LE than in LI (118 ± 63 minutes for LI and 163 ± 23 minutes for LE; mean ± standard deviation) (p = 0.027). At nadir value, dynamic peak vertical force was lower in LE than in LI (p = 0.007). For both dynamic and static evaluations, the nadir and the return to baseline force were delayed in LE (return to normal at 180–200 minutes) when compared with LI (130–140 minutes) (p < 0.005).Conclusions and clinical relevance
The addition of epinephrine to lidocaine prolonged the duration and increased the intensity of the regional block, as verified by visual gait assessment and kinetic analysis. No significant difference was noted between treatments regarding sensory blockade. Kinetic analysis could be useful to evaluate regional anesthetic effect in dogs. 相似文献154.
Jinek M Chylinski K Fonfara I Hauer M Doudna JA Charpentier E 《Science (New York, N.Y.)》2012,337(6096):816-821
Clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated (Cas) systems provide bacteria and archaea with adaptive immunity against viruses and plasmids by using CRISPR RNAs (crRNAs) to guide the silencing of invading nucleic acids. We show here that in a subset of these systems, the mature crRNA that is base-paired to trans-activating crRNA (tracrRNA) forms a two-RNA structure that directs the CRISPR-associated protein Cas9 to introduce double-stranded (ds) breaks in target DNA. At sites complementary to the crRNA-guide sequence, the Cas9 HNH nuclease domain cleaves the complementary strand, whereas the Cas9 RuvC-like domain cleaves the noncomplementary strand. The dual-tracrRNA:crRNA, when engineered as a single RNA chimera, also directs sequence-specific Cas9 dsDNA cleavage. Our study reveals a family of endonucleases that use dual-RNAs for site-specific DNA cleavage and highlights the potential to exploit the system for RNA-programmable genome editing. 相似文献
155.
156.
157.
Fraipont A Van Erck E Ramery E Fortier G Lekeux P Art T 《The Canadian veterinary journal. La revue veterinaire canadienne》2012,53(3):311-314
A field test and a standardized treadmill test were used to assess fitness in endurance horses. These tests discriminated horses of different race levels: horses participating in races of 120 km and more showed higher values of VLA4 (velocity at which blood lactate reached 4 mmol/L) and V200 (velocity at which heart rates reached 200 beats per min) than horses of lower race levels. 相似文献
158.
Research efforts aim to enhance fundamental understanding about the role of salt in cereal products. Such knowledge may open new strategies for salt reduction in respective product categories. A model system, containing pregelatinized starch, glucose, and amino acids heated at 230°C for up to 10 min demonstrated that NaCl leads to darker products compared with the same model heated without NaCl (P < 0.05). The same trend was observed in wheat breakfast cereal flakes toasted at 230°C. The present study investigated two hypotheses how salt may influence color formation through Maillard Reaction: 1) hygroscopic behavior of salt may change the retention of water during heating and encourage Maillard reactions by improving mobility of reactants; 2) salt has a plasticizing effect and the presence of salt might keep the product in a rubbery state longer while heating, hence improving mobility and Maillard reactions of reactants. The same models (pregelatinized starch, glucose, and amino acids) mixed with several types of plasticizers (NaCl, KCl, or trehalose) and a blank without plasticizer were made and heat‐treated under controlled conditions. The presence of plasticizers always led to darker products but no correlation was found between color formation, the hygroscopic behavior of the system, and its glass transition temperature as measured by phase transition analyzer. 相似文献
159.
Grisneaux E Dupuis J Pibarot P Bonneau NH Charette B Blais D 《Journal of the American Veterinary Medical Association》2003,223(7):1006-1012
OBJECTIVE: To determine whether postoperative administration of ketoprofen or carprofen had any effects on short- or long-term results of femoral head and neck excision (FHNE) in dogs. DESIGN: Prospective randomized controlled trial. ANIMALS: 40 client-owned, large-breed dogs undergoing FHNE and 15 healthy large-breed dogs used as controls for hip joint angle measurements and force plate analyses. PROCEDURE: Dogs undergoing FHNE were treated with ketoprofen, carprofen, or a placebo for 21 days after surgery. Hip joint abduction and extension angles were measured at the end of surgery and 120 days later. Lameness scores were assigned, and force plate analyses were performed on days 3, 15, and 120. RESULTS: There were no significant differences among treatment groups in regard to hip joint angles or lameness scores. Force plate analysis revealed that dogs in all 3 treatment groups bore consistently less weight on the operated limb than did control dogs for the duration of the study. Dogs receiving ketoprofen had greater peak propulsive force at a walk on day 3 and greater peak vertical force at a walk on day 15 than did dogs receiving the placebo. Treatment of an acute condition and preservation of the lesser trochanter, but not postoperative analgesic administration, were positively associated with ground reaction forces on day 120. Owners of 12 of 31 dogs indicated that the dog's gait worsened for a few days after discontinuation of analgesic administration. CONCLUSIONS AND CLINICAL RELEVANCE: Administration of ketoprofen or carprofen after surgery was not associated with long-term results of FHNE, probably because of the impact of other factors. Because some owners noticed worsening of the lameness following cessation of analgesic administration in the present study, it is possible that longer administration would have improved long-term results. 相似文献
160.
Effects of oral administration of meloxicam,carprofen, and a nutraceutical on thyroid function in dogs with osteoarthritis
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Sauvé F Paradis M Refsal KR Moreau M Beauchamp G Dupuis J 《The Canadian veterinary journal. La revue veterinaire canadienne》2003,44(6):474-479
The purpose of this study was to evaluate the effect of the administration of meloxicam; carprofen; and a slow-acting disease modifying osteoarthritis agent, that contains chondroitin sulfate, purified glucosamine, and manganese ascorbate (CS-G-M), on thyroid function in dogs. Forty-six healthy (except for osteoarthritis) euthyroid dogs were blindly assigned to 3 treatment groups: meloxicam, carprofen, and CS-G-M. Each group received the recommended dose of the drug for 60 days. Sixteen other osteoarthritic euthyroid dogs, which received a placebo, were used as a control group to validate the study. For all groups, blood samples were collected on days 0, 30, and 60 to evaluate the serum total and free thyroxine, and endogenous thyrotropin concentrations. There were no significant differences among the treatment groups at each time or within each group over a 60-day period for all parameters. Moreover, none of these values were within the hypothyroid range. Based on the results of this study, the administration of meloxicam, carprofen, and CS-G-M did not affect canine thyroid function evaluation. 相似文献