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71.

Objectives

To validate a thermal threshold (TT) nociceptive model in bearded dragons (Pogona vitticeps) and to document TT changes after administration of morphine.

Study design

A two-part randomized, blinded, controlled, experimental study.

Animals

Five adult bearded dragons (242–396 g).

Methods

A TT device delivered a ramped nociceptive stimulus (0.6 °C second?1) to the medial thigh until a response (leg kick/escape behavior) was observed or maximum (cut-off) temperature of 62 °C was reached. In phase I, period 1, six TT readings were determined at 20 minute intervals for evaluation of repeatability. Two of these readings were randomly assigned to be sham to assess specificity of the behavioral response. The same experiment was repeated 2 weeks later (period 2) to test reproducibility. In phase II, animals were administered either intramuscular morphine (10 mg kg?1) or saline 0.9%. TTs (maximum 68 °C) were determined before and 2, 4, 8, 12 and 24 hours after treatment administration. Data were analyzed using one-way anova (temporal changes and repeatability) and paired t tests (reproducibility and treatment comparisons) using Bonferroni correction (p < 0.05).

Results

Mean TT values were 57.4 ± 3.8 °C and 57.3 ± 4.3 °C for periods 1 and 2, respectively. Data were repeatable within each period (p = 0.83 and p = 0.07, respectively). Reproducibility between periods was remarkable (p = 0.86). False-positive responses during sham testing were 10%. TTs were significantly increased after morphine administration at 2, 4 and 8 hours compared with baseline, and at 2 and 4 hours compared with saline 0.9%. The highest TT was 67.7 ± 0.7 °C at 4 hours after morphine administration.

Conclusions and clinical relevance

Testing was repeatable, reproducible and well tolerated in bearded dragons. TT nociceptive testing detected morphine administration and may be suitable for studying opioid regimens in bearded dragons.  相似文献   
72.
6α,7β-Dihydroxyvouacapan-17β-oic acid (1) and methyl 6α,7β-dihydroxyvouacapan-17β-oate (8) were isolated from Pterodon polygalaeflorus Benth. 1 was modified to obtain 6α-hydroxyvouacapan-7-β,17β lactone (2). Then, 6-oxovouacapan-7β,17β lactone (3) was obtained from 2. The furanoditerpene ester derivatives: propyl 7β-hydroxy-6-oxovouacapan-17β-oate (4), butyl 7β-hydroxy-6-oxovouacapan-17β-oate (5), 2-methoxyethyl 7β-hydroxy-6-oxovouacapan-17β-oate (6) and 3-methylbut-2-enyl 7β-hydroxy-6-oxovouacapan-17β-oate (7) were synthesized from (3) and methyl 6α,7β-thiocarbonyldioxyvouacapan-17β-oate (9) was obtained from (8). In this work, the lactone ester derivatives 4-7 and 9 were tested on photosynthetic activities in an attempt to search for new compounds as potential herbicide agents that affect photosynthesis. All compounds inhibited ATP synthesis and electron flow from water to MV, therefore, they act as Hill reaction inhibitors, being 4- to 9-fold more potent than 2 and 3 as inhibitors of ATP synthesis. Their interaction site was located at PSII in a similar way to diuron. Furthermore, furanoditerpene esters 6 and 7 act as uncouplers, and were corroborated by enhancement of the light-activated Mg2+-ATPase, while 5 act as an energy transfer inhibitor. Finally 5-7 behave as herbicides, since they inhibit the biomass production of weeds assay.  相似文献   
73.
Cryopreservation of selected genotypes of European chestnut and cork oak was carried out in two laboratories in a project involving conservation of field collections. Plant material was selected on the basis of disease resistance (chestnut), growth habit, phytosanitary performance and cork quality (cork oak). The cryopreservation technique comprised of vitrification of shoot apices isolated from in vitro stock shoot cultures (chestnut) and somatic embryos (cork oak). Forty-three out of 46 chestnut genotypes assayed survived the freezing process, but only 63% recovered their capacity to produce new shoots. After completion of multiplication and rooting steps, the surviving shoots produced plants that were morphologically identical to those derived from non-supercooled material. All 51 cork oak genotypes withstood freezing and were able to produce new somatic embryos through a process of secondary embryogenesis. Multiplication and germination of the recovered embryos enabled production of plants that were morphologically identical to those derived from non-supercooled material. In light of the results obtained, long-term cryopreservation of these species is feasible, thereby ensuring conservation of valuable genotypes during field evaluation.  相似文献   
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76.
Almond ( Prunus dulcis ) has been widely used in all sorts of food products (bakery, pastry, snacks), mostly due to its pleasant flavor and health benefits. However, it is also classified as a potential allergenic seed known to be responsible for triggering several mild to life-threatening immune reactions in sensitized and allergic individuals. Presently, eight groups of allergenic proteins have been identified and characterized in almond, namely, PR-10 (Pru du 1), TLP (Pru du 2), prolamins (Pru du 2S albumin, Pru du 3), profilins (Pru du 4), 60sRP (Pru du 5), and cupin (Pru du 6, Pru du γ-conglutin), although only a few of them have been tested for reactivity with almond-allergic sera. To protect sensitized individuals, labeling regulations have been implemented for foods containing potential allergenic ingredients, impelling the development of adequate analytical methods. This work aims to present an updated and critical overview of the molecular characterization and clinical relevance of almond allergens, as well as review the main methodologies used to detect and quantitate food allergens with special emphasis on almond.  相似文献   
77.
Pinus pinaster wood samples were subjected to double hydrothermal processing. The liquors coming from the second stage, containing soluble saccharides of polymeric or oligomeric nature from hemicelluloses (POHs), were subjected to membrane processing (operating in discontinuous diafiltration) for refining and fractionation. Refined POH fractions were characterized by matrix-assisted laser desorption/ionization time of flight mass spectrometry and chromatographic techniques. The most complex POH component was made up of 14 hexoses and contained 4 acetyl groups. The fermentability of purified POHs by human fecal inocula was assessed by measuring both carbon source consumption and formation of short-chain fatty acids. The bifidogenic ability of POHs was confirmed by fluorescence in situ hybridization. The stimulatory effects on the bifidobacterial population reached by POHs were of the same order as those obtained with commercial fructooligosaccharides.  相似文献   
78.
In this study, the hypothesis that food-derived opioid peptides besides β-casomorphin 7 might modulate the production of mucin via a direct action on epithelial goblet cells was investigated in HT29-MTX cells used as a model of human colonic epithelium. Seven milk whey or casein peptides, a human milk peptide, and a wheat gluten-derived peptide with proved or probable ability to bind μ- or δ-opioid receptors were tested on the cell culture. Significantly increased secretion of mucins was found after exposure to six of the assayed peptides, besides the previously described β-casomorphin 7, as measured by an enzyme-linked lectin assay (ELLA). Human β-casomorphin 5 and α-lactorphin were selected to study the expression of mucin 5AC gene (MUC5AC), the HT29-MTX major secreted mucin gene. α-Lactorphin showed increased expression of MUC5AC from 4 to 24 h (up to 1.6-fold over basal level expression), although differences were statistically different only after 24 h of exposure. However, this increased expression of MUC5AC did not reach significance after cell treatment with human β-casomorphin 5. In conclusion, six food-derived peptides have been identifed with described or probable opioid activity that induce mucin secretion in HT29-MTX cells. Concretely, α-lactorphin is able to up-regulate the expression of the major secreted mucin gene encoded by these cells.  相似文献   
79.
80.
The impact of the topographical position on soil properties was evaluated in an olive grove with traditional tillage. Three topographical positions: summit, backslope and toeslope were chosen for evaluation. The soil samples were taken from four soil sections of 0·25 m (0–1 m). The soil organic carbon (SOC) and N content increased along the downslope direction (5·5, 6·5 and 7·1 g C kg−1 and 0·3, 0·8 and 0·9 g N kg−1 in the surface layer in the summit, backslope and toeslope respectively) as well as SOC and N stocks, considering the two first soil sections. In addition, there was movement of the most erodible textural fraction (silt). However, the total SOC stock (refer to 1 m of depth) did not vary with respect to the topographical position, but the total N stock (refer to 1 m of depth) varied significantly. These increases were due to erosion processes that occur along the toposequence, leading to organic matter transfers from the summit to the toeslope. All the stratification ratios calculated were lower than 2, indicating the low quality of the soils. Therefore, alternative management techniques that avoid soil erosion must be considered in olive grove in order to increase the soil quality and fertility. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
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