Effect of repeated freeze-thaw cycles on routine plasma biochemical constituents in canine plasma     

Reynolds B  Taillade B  Médaille C  Palenché F  Trumel C  Lefebvre HP 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2006,35(3):339-340

BACKGROUND: The effect of repeated freeze-thaw cycles on plasma constituents has not been assessed in dogs, although such a procedure is not uncommon to use in routine laboratory practice. OBJECTIVE: To assess the effect of freeze-thaw cycles on routine plasma constituents in healthy dogs. METHODS: Six healthy adult dogs were used. Blood was sampled and placed in heparinized tubes. After centrifugation, plasma was separated into 5 aliquots. One aliquot was considered as the reference aliquot and used immediately for the assay of all of the biochemical constituents. All of the other aliquots were stored at 20 degrees C. Three aliquots underwent 1, 2, or 3 freeze-thaw cycles during a 1- to 3-day period. The last aliquot remained at 20 degrees C throughout the study and was thawed on the third day. The following biochemical constituents were assayed: glucose, urea, creatinine, total proteins, sodium, potassium, chloride, calcium, phosphates, aspartate aminotransferase (AST), alanine aminotransferase (ALT), creatine kinase (CK), and alkaline phosphatase (ALP). RESULTS: No clinically relevant change was observed between the different aliquots for all of the constituents. CONCLUSION: Repeated freeze-thaw cycles do not cause changes in the biochemical constituents studied in canine plasma.  相似文献   

Cyclooxygenase-2 expression in normal and neoplastic canine mammary cell lines     

Brunelle M  Sartin EA  Wolfe LG  Sirois J  Doré M 《Veterinary pathology》2006,43(5):656-666

Mammary cancer is the most common cancer in female dogs. Induction of cyclooxygenase-2 (COX-2), a key enzyme in prostaglandins (PGs) biosynthesis, has been demonstrated in various cancers in humans and dogs, including mammary cancer. The objective of this study was to investigate the expression and regulation of COX-2 in canine mammary epithelial cells. Cell lines derived from normal and neoplastic canine mammary glands were cultured in the absence or presence of phorbol 12-myristate 13-acetate (PMA), and immunoblots, immunocytochemistry, radioimmunoassays, and a cell proliferation assay were used to study COX-2 expression and PGs production. Results showed that the neoplastic cell line CMT12 constitutively overexpressed COX-2 protein whereas other mammary cell lines expressed low to undetectable basal levels of COX-2 protein. Basal PGE(2) production was significantly higher (P < .05) in CMT12 compared to other cell lines. Levels of COX-2 protein in CMT12 decreased in a time-dependent manner with serum starvation, and PMA stimulation induced a strong time-dependent increase in COX-2 protein. Treatment of CMT12 cells with NS-398 (a specific COX-2 inhibitor) significantly blocked PGE(2) synthesis and reduced cell proliferation (P < .05). These results indicate that some neoplastic canine mammary cell lines constitutively overexpress COX-2, and that COX-2 inhibition decreases PGE(2) production and cell proliferation, supporting a role for COX-2 and PGs in canine mammary oncogenesis.  相似文献   

Changes in Eucalyptus globulus Labill. saplings growth and physiological parameters following fire-induced stem and crown damage in a plantation in north-western Spain     

Enrique Jiménez  José A. Vega  Cristina Fernández  Pedro Pérez-Gorostiaga  Pedro Cuiñas  Teresa Fonturbel  Margarita Alonso  María J. Rozados  Salvador Bará 《European Journal of Forest Research》2012,131(6):1967-1978

Stems and crowns of young Eucalyptus globulus Labill. saplings were experimentally damaged by fire to assess the short-term effects on tree growth and selected physiological parameters (stem sap flow density, electrical resistance of stem cambium and leaf stomatal conductance). Four different treatments were considered: partial stem damage (42 % of the stem circumference girdled by the direct application of heat in the cambium zone), crown foliage damage (56 % of crown volume scorched by heating the foliage with a torch), combined stem and crown damage, and no damage (control). Saplings displayed high sensitivity to crown scorching, in terms of basal area growth. The relative growth of the basal area of crown-damaged and stem + crown-damaged trees was, respectively, 3.1 and 6.2 times lower than that of undamaged trees for the 4 months following treatment. In contrast, stem injury alone did not have any negative effect on stem growth. The results suggest that tree growth is scarcely affected by low intensity surface fire and prescribed burning that do not affect the crown. Sap flow density, cambial electrical resistance and leaf stomatal conductance were useful indicators of the loss of physiological activity caused by fire. Although in the case of partial crown damage these parameters reflected a slight compensatory effect, the response was not sufficient to balance the loss of photosynthetic area. The study only focused on the initial effects of fire-related damage, and further research is clearly needed to determine the long-term effects of such damage.  相似文献   

Population variability based on the morphometry and chemical composition of the acorn in Holm oak (Quercus ilex subsp. ballota [Desf.] Samp.)     

José Valero Galván  Jesús J. Jorrín Novo  Augusto Gómez Cabrera  David Ariza  Juan García-Olmo  Rafael Ma Navarro Cerrillo 《European Journal of Forest Research》2012,131(4):893-904

We have studied in this work the natural variability in Holm oak (Quercus ilex subsp. ballota) by analyzing acorn morphometry and chemical composition in 13 populations from the Andalusia region (southern Spain). Acorn morphometry showed statistic significant differences between the populations with a higher acorn weight, length, and diameter in the northern provenances (TJA, GSE, CTH, CHU, APS, and PCO), while the Southern provenances (RMA, SAA, CCO, BCA, and SCA) showed lower value that even decreased with the altitude. Acorn chemical composition also showed statistic significant differences between populations. Morphometry and chemical composition data were subjected to clustering analysis, and two major clusters were detected. This analysis showed that northern populations (CTH, TJA, SCA, CHU, PCO, GSE, and APS) showed a tendency to present values highest in acorn weight (5.42?g vs. 3.21?g); acorn length (37.21?mm vs. 28.73?mm); acorn diameter (16.12?mm vs. 13.79?mm); ash (1.88% vs. 1.55%); protein (4.82% vs. 4.38%); fat (12.55% vs. 9.92%); and oleic acid (66.93 vs. 66.4%). On the contrary, Southern populations (SSA, VJA, CCO, BCA, RG, and RMA) showed a tendency to present values lowest in sugar (10.28% vs. 11.25%); energy (20,076.71?kJ/kg vs. 20,149.26?kJ/kg); palmitic (16.11% vs. 16.39%) and linoleic acids (13.07% vs. 13.11%). The populations studied here seemed to integrate acorn morphology and chemical composition related to environmental conditions of the original provenances. These data have provided biochemical markers that help establish phylogenic associations between populations and also reveal potentially account as an alternative source for dietary nutrition.  相似文献   

Geographically structured and temporally unstable growth responses of Juniperus thurifera to recent climate variability in the Iberian Peninsula     

Lucía DeSoto  Jesús Julio Camarero  José Miguel Olano  Vicente Rozas 《European Journal of Forest Research》2012,131(4):905-917

Geographically structured tree-ring networks are needed to fully understand the spatiotemporal variability in climatic sensitiveness of trees and to study their future responses to global warming. We aim to identify the spatially constrained structure of radial-growth patterns of the Spanish juniper (Juniperus thurifera L.) and to assess whether their climate–growth responses were unstable during the late twentieth century. Tree–ring width chronologies were built for 13?J. thurifera stands in Spain using dendrochronological methods and related to monthly climatic data. Sites were grouped according to their growth patterns using hierarchical cluster analysis. The relationships among geographical, climatic and stand features and their influence on radial growth were evaluated using redundancy analysis. The climate–growth relationships and their temporal stability were assessed using Pearson’s and moving bootstrapped correlations, respectively. Stands formed three geographical groups according to their high-frequency growth variation: North West and Centre, North East and South East. We found that J. thurifera radial-growth patterns depended on geographical and climatic factors, but not on the stand structure, and responded to a northwest–southeast gradient of decreasing rainfall and influence of Atlantic Westerlies and Mediterranean cyclonic activity. The positive response to June precipitation was unstable during the late twentieth century and started earlier in populations from western mesic sites than in eastern xeric sites. This pattern may be related to either decreasing water availability in western than in eastern sites or the resilience of J. thurifera growth from xeric sites in response to the increasing summer aridity.  相似文献   

From points to numbers: a database-driven approach to convert terrestrial LiDAR point clouds to tree volumes   总被引：2，自引：0，他引：2  

Rüdiger Hildebrandt  André Iost 《European Journal of Forest Research》2012,131(6):1857-1867

Data provided by airborne LiDAR (Light Detection and Ranging) techniques are commonly used for measuring and monitoring of forest resources. In the last years, terrestrial laser scanning systems have also gained increasing attention as a ground-based application for individual tree measurements. The database-driven approach described in this article focuses on the calculation of single tree stem volumes from terrestrial laser scan data. A straightforward way of determining the volume of upright cylindrical objects is presented. Three-dimensional point data are split up into cylindrical sections whose diameters are used as basis for volume calculations. Tests conducted with a simple tree stem model show that results produced by the algorithm differ by less than 1?% from results obtained by manual section-wise cubing, which was applied to gather reference data. The method we present offers a perspective on non-destructive techniques of volume data acquisition for forest resource assessments. It is capable of reducing the error of single tree biomass estimations which in turn would improve the reliability of biomass inventories. Also, other tasks such as forest inventories or forest management plans can benefit from more accurate estimations and smaller prediction errors.  相似文献   

Impact of the pinewood nematode, Bursaphelenchus xylophilus, on gross calorific value and chemical composition of Pinus pinaster woody biomass     

Valeria Reva  Luís Fonseca  José L. Lousada  Isabel Abrantes  Domingos X. Viegas 《European Journal of Forest Research》2012,131(4):1025-1033

The pinewood nematode (PWN), Bursaphelenchus xylophilus, the causal agent of the pine wilt disease, has been detected in several regions of Portugal affecting Pinus pinaster, a coniferous species of a great economic value. The nematodes, migrating through resin canals and feeding on parenchyma cells, induce rapid metabolic changes in ray parenchyma cells, cavitation areas, and denaturation and necrosis of parenchyma and cambial cells. To understand how anatomic changes and biochemical incidences of tree defense reactions affect the technological parameters of the wood, the gross calorific value (GCV) and chemical composition of PWN-infected and -uninfected P. pinaster wood were evaluated. The GCV was determined using Parr 6300 Automatic Isoperibol Calorimeter, and chemical composition analysis was performed by determining the contents of carbon, hydrogen, nitrogen, sulfur and Ash on complete and instant oxidation of samples by “flash” combustion. The Student’s t test with Welch correction was used for statistical data analysis. The difference between the GCV and chemical composition for PWN-infected and -uninfected P. pinaster wood was statistically significant for the GCV and for hydrogen and nitrogen contents. The carbon, oxygen, sulfur and Ash contents did not differ statistically. The GCV of PWN-infected wood varied between the highest value of hardwood and the lowest value of softwood. This interdisciplinary study stresses the important technological and economic aspects, namely the impact of PWN on wood properties and the suitability of infected P. pinaster wood for use in the wood-processing and energy industries.  相似文献   

Melanesian blond hair is caused by an amino acid change in TYRP1     

Kenny EE  Timpson NJ  Sikora M  Yee MC  Moreno-Estrada A  Eng C  Huntsman S  Burchard EG  Stoneking M  Bustamante CD  Myles S 《Science (New York, N.Y.)》2012,336(6081):554

Naturally blond hair is rare in humans and found almost exclusively in Europe and Oceania. Here, we identify an arginine-to-cysteine change at a highly conserved residue in tyrosinase-related protein 1 (TYRP1) as a major determinant of blond hair in Solomon Islanders. This missense mutation is predicted to affect catalytic activity of TYRP1 and causes blond hair through a recessive mode of inheritance. The mutation is at a frequency of 26% in the Solomon Islands, is absent outside of Oceania, represents a strong common genetic effect on a complex human phenotype, and highlights the importance of examining genetic associations worldwide.  相似文献   

Immunology. HD6 defensin nanonets     

AJ Ouellette  ME Selsted 《Science (New York, N.Y.)》2012,337(6093):420-421

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A PCR‐based method for discriminating between high molecular weight glutenin subunits Bx7 and Bx7* in Triticum aestivum L.     

Araceli Espí  Patricia Giraldo  Marta Rodriguez‐Quijano  José M. Carrillo 《Plant Breeding》2012,131(5):571-573

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