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E Decreased (e + decreased)
Selected AbstractsTranspiration and stomatal conductance across a steep climate gradient in the southern Rocky MountainsECOHYDROLOGY, Issue 3 2008Nate G. McDowell Abstract Transpiration (E) is regulated over short time periods by stomatal conductance (Gs) and over multi-year periods by tree- and stand-structural factors such as leaf area, height and density, with upper limits ultimately set by climate. We tested the hypothesis that tree structure, stand structure and Gs together regulate E per ground area (Eg) within climatic limits using three sites located across a steep climatic gradient: a low-elevation Juniperus woodland, a mid-elevation Pinus forest and a high-elevation Picea forest. We measured leaf area : sapwood area ratio (Al : As), height and ecosystem sapwood area : ground area ratio (As : Ag) to assess long-term structural adjustments, tree-ring carbon isotope ratios (,13C) to assess seasonal gas exchange, and whole-tree E and Gs to assess short-term regulation. We used a hydraulic model based on Darcy's law to interpret the interactive regulation of Gs and Eg. Common allometric dependencies were found only in the relationship of sapwood area to diameter for pine and spruce; there were strong site differences for allometric relationships of sapwood area to basal area, Al : As and As : Ag. On a sapwood area basis, E decreased with increasing elevation, but this pattern was reversed when E was scaled to the crown using Al : As. Eg was controlled largely by As : Ag, and both Eg and Gs declined from high- to low-elevation sites. Observation-model comparisons of Eg, Gs and ,13C were strongest using the hydraulic model parameterized with precipitation, vapour pressure deficit, Al : As, height, and As : Ag, supporting the concept that climate, Gs, tree- and stand-structure interact to regulate Eg. Copyright © 2008 John Wiley & Sons, Ltd. [source] Vitamin E does not reduce the side-effects of isotretinoin in the treatment of acne vulgarisINTERNATIONAL JOURNAL OF DERMATOLOGY, Issue 3 2005Sadiye Kus Background, Isotretinoin is widely used in the treatment of severe, recalcitrant, nodular acne. Mucocutaneous side-effects are seen in the great majority of patients and some of them have elevations in their serum lipid and liver enzyme profiles. Recently, it has been shown that addition of vitamin E decreased the toxicity of high-dose retinoids. Objective, The purpose of this investigator-blinded, randomized study was to assess whether vitamin E would reduce the side-effects of isotretinoin in the treatment of acne vulgaris. Methods, Eighty two patients were randomly assigned to one of two treatment groups with isotretinoin (1 mg/kg/day) alone or combined with vitamin E (800 IU/day). The treatment duration was 16 weeks. Mucocutaneous side-effects such as facial erythema, facial dryness, cheilitis and serum lipid and liver enzyme profiles were assessed. Results, There was no difference in the incidence and severity of side-effects related to isotretinoin between the two treatment groups. Conclusion, Eight hundred IU/day vitamin E did not improve the side-effects of 1 mg/kg/day of isotretinoin in the treatment of acne vulgaris. [source] BACTERIA-INDUCED MOTILITY REDUCTION IN LINGULODINIUM POLYEDRUM (DINOPHYCEAE),JOURNAL OF PHYCOLOGY, Issue 4 2008Xavier Mayali Biotic factors that affect phytoplankton physiology and behavior are not well characterized but probably play a crucial role in regulating their population dynamics in nature. We document evidence that some marine bacteria can decrease the swimming speed of motile phytoplankton through the release of putative protease(s). Using the dinoflagellate Lingulodinium polyedrum (F. Stein) J. D. Dodge as a model system, we showed that the motility-reducing components of bacterial-algal cocultures were mostly heat labile, were of high molecular weight (>50 kDa), and could be partially neutralized by incubations with protease inhibitors. We further showed that additions of the purified protease pronase E decreased dinoflagellate swimming speed in a concentration-dependent manner. We propose that motility can be used as a marker for dinoflagellate stress or general unhealthy status due to proteolytic bacteria, among other factors. [source] The comparison of vitamin C and vitamin E on the protein oxidation of diabetic ratsAUTONOMIC & AUTACOID PHARMACOLOGY, Issue 5 2001H. D. Je Summary 1 We measured the plasma glucose and the glycosylated haemoglobin at the time of sacrifice in streptozotocin-induced diabetic mellitus (DM) rats. 2 In diabetic rats, plasma glucose and glycosylated haemoglobin was increased as compared with normal rats, and vitamin E inhibited the increase of glycosylated haemoglobin level but vitamin C had no effect. 3 The peroxidized proteins and lipids from the diabetic organs such as liver or kidney were measured to assess the oxidative damage. The 2,4-dinitrophenyl-hydrazine (DNPH) incorporation method was used to measure the peroxidized protein. In diabetic rats, DNPH incorporation was increased as compared with normal rats and vitamin E also inhibited the increase of DNPH incorporation but vitamin C had no effect. It suggests that the protein oxidation occurred on the liver in diabetic rats and the oxidative stress is general in the diabetic condition. 4 We measured the systolic arterial pressure and mean arterial pressure in normal rats, nephrectomy (NEPH)-rats, diabetic rats (DM), and NEPH-diabetic rats (NEPH-DM). Blood pressure was significantly increased in DM and NEPH-DM as compared with normal rats. 5 In conclusion, plasma glucose, glycosylated haemoglobin, and the oxidation of proteins or lipid were increased in diabetic rats. Vitamin E decreased the plasma glucose, glycosylated haemoglobin and the oxidation of proteins and lipid, but vitamin C had no effects. [source] | ||||||||||