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Showing papers by "University of Córdoba (Spain) published in 1999"


Journal ArticleDOI
TL;DR: The phosphomolybdenum method is routinely applied in the laboratory to evaluate the total antioxidant capacity of plant extracts and to determine vitamin E in a variety of grains and seeds, including corn and soybean.

4,644 citations


Journal ArticleDOI
TL;DR: In this paper, the synthesis, properties and applications of layered double hydroxides (LDHs) are reviewed, also known as anionic clays or hydrotalcite-like materials containing intercalated anions constituted by metal complexes or oxometalates.

795 citations


Journal ArticleDOI
TL;DR: Nitrogen is a basic element for life because it is a component of the two preeminent biological macromolecules: proteins and nucleic acids.
Abstract: Nitrogen is a basic element for life because it is a component of the two preeminent biological macromolecules: proteins and nucleic acids. Nitrogen exists in the biosphere in several oxidation states, from N(V) to N(−III). Interconversions of these nitrogen species constitute the global

533 citations


Journal ArticleDOI
TL;DR: It is demonstrated that yeast cells control glycerol accumulation in part via a regulated, Fps1p‐mediated export of glyceroled, which seems to be independent of the known yeast osmosensing HOG and PKC signalling pathways.
Abstract: The accumulation of compatible solutes, such as glycerol, in the yeast Saccharomyces cerevisiae, is a ubiquitous mechanism in cellular osmoregulation. Here, we demonstrate that yeast cells control glycerol accumulation in part via a regulated, Fps1p-mediated export of glycerol. Fps1p is a member of the MIP family of channel proteins most closely related to the bacterial glycerol facilitators. The protein is localized in the plasma membrane. The physiological role of Fps1p appears to be glycerol export rather than uptake. Fps1 delta mutants are sensitive to hypo-osmotic shock, demonstrating that osmolyte export is required for recovery from a sudden drop in external osmolarity. In wild-type cells, the glycerol transport rate is decreased by hyperosmotic shock and increased by hypo-osmotic shock on a subminute time scale. This regulation seems to be independent of the known yeast osmosensing HOG and PKC signalling pathways. Mutants lacking the unique hydrophilic N-terminal domain of Fps1p, or certain parts thereof, fail to reduce the glycerol transport rate after a hyperosmotic shock. Yeast cells carrying these constructs constitutively release glycerol and show a dominant hyperosmosensitivity, but compensate for glycerol loss after prolonged incubation by glycerol overproduction. Fps1p may be an example of a more widespread class of regulators of osmoadaptation, which control the cellular content and release of compatible solutes.

386 citations


Journal ArticleDOI
TL;DR: Analysis of the purified recombinant c‐Jun DNA binding domain for redox‐dependent thiol modifications and concomitant changes in DNA binding activity shows that changes in the ratio of reduced to oxidized glutathione provide the potential to oxidize c‐ Jun sulfhydryls by mechanisms that include both protein disulfide formation and S‐glutathiolation.
Abstract: Redox control of the transcription factor c-Jun maps to a single cysteine in its DNA binding domain. However, the nature of the oxidized state of this cysteine and, thus, the potential molecular mechanisms accounting for the redox regulation of c-Jun DNA binding remain unclear. To address this issue, we have analyzed the purified recombinant c-Jun DNA binding domain for redox-dependent thiol modifications and concomitant changes in DNA binding activity. We show that changes in the ratio of reduced to oxidized glutathione provide the potential to oxidize c-Jun sulfhydryls by mechanisms that include both protein disulfide formation and S-glutathiolation. We provide evidence that S-glutathiolation, which is specifically targeted to the cysteine residue located in the DNA binding site of the protein, may account for the reversible redox regulation of c-Jun DNA binding. Furthermore, based on a molecular model of the S-glutathiolated protein, we discuss the structural elements facilitating S-glutathiolation and...

289 citations


Journal ArticleDOI
TL;DR: Grape marc resulting from red winemaking was extracted with a mixture of ethyl acetate and water in order to obtain its phenolic compounds with a view to their use as food lipid antioxidants as mentioned in this paper.

246 citations


Journal ArticleDOI
TL;DR: The results show that leptin, depending on the state of sexual maturation, is able to inhibit testosterone secretion acting at the testicular level, and suggest that the actions of leptin on the reproductive system are complex and are probably carried out at different levels of the hypothalamic-pituitary-gonadal axis.
Abstract: Leptin, the product of the ob gene, has emerged recently as a pivotal signal in the regulation of fertility. Although the actions of leptin in the control of reproductive function are thought to be exerted mainly at the hypothalamic level, the potential direct effects of leptin at the pituitary and gonadal level have been poorly characterised. In the present study, we first assessed the ability of leptin to regulate testicular testosterone secretion in vitro. Secondly, we aimed to evaluate whether leptin can modulate basal gonadotrophin and prolactin (PRL) release by incubated hemi-pituitaries from fasted male rats. To attain the first goal, testicular slices from prepubertal and adult rats were incubated with increasing concentrations (10(-9)-10(-7) M) of recombinant leptin. Assuming that in vitro testicular responsiveness to leptin may be dependent on the background leptin levels, testicular tissue from both food-deprived and normally-fed animals was used. Furthermore, leptin modulation of stimulated testosterone secretion was evaluated by incubation of testicular samples with different doses of leptin in the presence of 10 IU human chorionic gonadotrophin (hCG). In addition, analysis of leptin actions on pituitary function was carried out using hemi-pituitaries from fasted adult male rats incubated in the presence of increasing concentrations (10(-9)-10(-7) M) of recombinant leptin. Serum testosterone levels, and basal and hCG-stimulated testosterone secretion by incubated testicular tissue were significantly decreased by fasting in prepubertal and adult male rats. However, a significant reduction in circulating LH levels was only evident in adult fasted rats. Doses of 10(-9)-10(-7) M leptin had no effect on basal or hCG-stimulated testosterone secretion by testes from prepubertal rats, regardless of the nutritional state of the donor animal. In contrast, leptin significantly decreased basal and hCG-induced testosterone secretion by testes from fasted and fed adult rats. In addition, 10(-9) M leptin inhibited LH and FSH secretion by incubated hemi-pituitaries from fasted adult males, whereas, at all doses tested, it was ineffective in modulating PRL release. Our results show that leptin, depending on the state of sexual maturation, is able to inhibit testosterone secretion acting at the testicular level. Furthermore, the present data suggest that the actions of leptin on the reproductive system are complex and are probably carried out at different levels of the hypothalamic-pituitary-gonadal axis.

225 citations


Journal ArticleDOI
01 Jun 1999-Catena
TL;DR: In this paper, a study has been conducted to describe the different types of ephemeral gullies and to determine their origin, evolution and importance as sediment sources, and three main types were identified according to their origin.
Abstract: Ephemeral gully erosion is a common type of water erosion in the loamy soils formed on the Miocene Marls of southern Navarra. A study has been conducted to describe the different types of ephemeral gullies and to determine their origin, evolution and importance as sediment sources. Three main types were identified according to their origin: classic ephemeral gullies formed within the same field where runoff starts, drainage ephemeral gullies collecting the runoff from another upstream area, and discontinuity ephemeral gullies due to some abrupt slope change in the landscape. During 2 consecutive years of normal precipitation, ephemeral gully erosion has caused significant soil losses, locally over 2.66 kg m−2 yr−1, which is above tolerable levels. In each year, one short and intense rainfall event has been responsible for almost all soil losses from ephemeral gullies. The main cause of gully formation is the lack of any proper waterway for conveying water excess. Conventional tillage practices provoked gully occurrence, while the maintenance of stubble or vegetation cover completely prevented their formation. Although farmers refill gullies every year, they reappear at the same position if no preventive measures are taken. Early winter has been the most critical period for gully formation, when the soil is wetter and the surface cover is scarce. But a strong summer thunderstorm also caused severe gully erosion in unprotected soils. Two simple topographic indices based on the area and the slope of the watersheds are useful to describe total soil losses.

221 citations


Journal ArticleDOI
TL;DR: The results show that CD69‐mediated NK cytotoxicity can be abrogated by CD94 stimulation in NK cells expressing the CD94 inhibitory form of the receptor, indicating that CD94 regulates the cytotoxic events initiated by a wide variety of NK activatory receptors.
Abstract: CD69 is a differentiation antigen expressed shortly after activation on T lymphocytes and other cells of haematopoietic origin, including natural killer (NK) cells. The function of CD69 on T lymphocytes acting as a costimulatory molecule in proliferation and lymphokine secretion is well established. NK cells express CD69 after activation by different stimuli such as phorbol 12-myristate 13-acetate (PMA), interleukin (IL)-2, IL-12, interferon-alpha (IFN-alpha) or anti-CD16 monoclonal antibodies (mAbs). However, although it has been shown that CD69 triggers NK-cell-mediated cytolytic activity, its effect on other NK-cell functions has not been studied. Furthermore, the possible interaction of CD69 triggering with other C-lectin type inhibitory receptors is not known. Thus, the objective of this work is to determine whether CD69-mediated NK cytotoxicity can be regulated by CD94 inhibitory receptor and the role of CD69 on other NK-cell functions different of cytotoxicity. The results show that CD69-mediated NK cytotoxicity can be abrogated by CD94 stimulation in NK cells expressing the CD94 inhibitory form of the receptor, indicating that CD94 regulates the cytotoxic events initiated by a wide variety of NK activatory receptors. We also show that anti-CD69 mAbs, not only triggered NK cytotoxicity, but also induce NK-cell proliferation, CD25 and intracellular adhesion molecule-1 (ICAM-1) expression, TNF-alpha production and Ca2+ mobilization in preactivated NK cells. These results suggest that CD69 plays a crucial role in NK-cell function contributing to sustain NK-cell activation, as it has been previously demonstrated in T cells.

207 citations


Journal ArticleDOI
TL;DR: It is concluded that stent treatment for severe coarctation of aorta provides excellent immediate and long-term results in young adults and children, however, at early age, restenosis by intimal growth may develop.
Abstract: Experimental studies have shown that stents implanted at the aorta become incorporated within the aortic wall and can be further expanded in growing animals. Few clinical studies have shown that the stent repair of severe coarctation of aorta provides excellent initial results, and little is known on the follow-up of these patients. We assessed the immediate and follow-up results obtained in a series of 48 patients (mean age 14 ± 12 years) with severe coarctation of the aorta who were treated by Palmaz stent implantation; 30 of them (63%) underwent angiographic follow-up studies at a mean of 25 ± 11 months after treatment. Quantitative serial analysis of the aortogram (baseline, after treatment, and at follow-up) was performed. Significant relief (mean residual gradient 3 ± 4 mm Hg) was always obtained after stent implantation. The isthmus, when hypoplastic (60%), was always expanded with the stent. One associated aneurysm became occluded after the implant. Complications included aortic disruption, stent migration, and decreased or absent femoral pulses. At angiographic follow-up, the stent remained always in place, without recoil. In 22 patients (73%), there were no detectable neointimal proliferation at late angiogram; however, 8 patients (27%) had some degree of intimal thickening (1 to 5 mm), causing mild restenosis in 3 patients treated at early age, and nonsignificant lumen reduction in 5. The serial aortogram analysis revealed a minor but significant increase in nonstented aortic diameters that seemed related to the normal growth of children. No need for stent reexpansion was observed at 2-year follow-up (mean). Two patients (7%) developed late small aneurysm formation at the stented wall; both were occluded by the insertion of coils through the stent orifices. We conclude that stent treatment for severe coarctation of aorta provides excellent immediate and long-term results in young adults and children. However, at early age, restenosis by intimal growth may develop.

198 citations


Journal ArticleDOI
TL;DR: The acid-induced liquid−liquid phase separation of anionic surfactants in aqueous solutions, and its applicability to cloud point extraction methodology, were examined in this paper, where phase diagrams obtained (e.g., [HCl] vs [surfactant]) consisted of three regions: a homogeneous liquid region, two coexisting isotropic phases, and a solid region.
Abstract: The acid-induced liquid−liquid phase separation of anionic surfactants in aqueous solutions, and its applicability to cloud point extraction methodology, were examined. The phase diagrams obtained (e.g., [HCl] vs [surfactant]) consisted of three regions: a homogeneous liquid region, two coexisting isotropic phases, and a solid region. The breadth of each region was found to depend on the surfactant structure. The behavior of each phase was also examined in relation to temperature and added salts. The anionic surfactants investigated were sodium dodecyl sulfate (SDS), sodium dodecylbenzenesulfonic acid (SDBSA), sodium dodecanesulfonic acid (SDSA), and sodium dioctylsulfosuccinate (Aerosol OT). The use of anionic surfactant-mediated phase separations provided very high extraction efficiencies (80−100%) for pyrene in aqueous samples and various PAHs in a certified reference material (dried sewage sludge). The preconcentration factor achieved was found to be a function of both surfactant and acid concentrati...

Journal ArticleDOI
TL;DR: The long-term effects of two different tillage systems, conventional (CT) and no tillage (NT), were studied in an olive orchard in Santaella (Spain) for 15 years.
Abstract: The long-term effects of two different tillage systems, conventional (CT) and no tillage (NT), were studied in an olive orchard in Santaella (Southern Spain) for 15 years. In both tillage systems, two distinct zones developed in the orchard in relation to soil physical properties; one underneath the tree canopy, and the other in the rows between trees. Surface soil organic matter content, bulk density, cone index, macroscopic capillary length and hydraulic conductivity showed significant differences between tillage systems and positions. After 15 years, the NT treatment achieved greater bulk density and cone index values than CT. This compaction reduced the infiltration rate of NT soil with respect to CT, particularly in the rows between trees. Despite that reduction, the NT soil retained a moderate infiltration potential. That may be explained by the high infiltration rates and macroporosity of the zone beneath the tree, the temporary effects of tillage on infiltration and probably by the self-repair of soil structure in the Vertisol studied. Yield was not affected by tillage except in one year with very low precipitation, where NT significantly yielded more than CT. The reduction in infiltration in NT must have been compensated by unknown factors that improve the tree water supply in drought years.

Journal ArticleDOI
TL;DR: In this paper, a critical overview is presented of conventional methods (based on either organic solvent extraction or distillation) and new alternatives (including microwave-assisted extraction (MAE) as well as supercritical CO2 (SC-CO2) extraction and subcritical water extraction) for the isolation of essential oils from plants.
Abstract: Attention is drawn to the use of new and clean alternative methods for the isolation of essential oils from plants A critical overview is presented of conventional methods (based on either organic solvent extraction or distillation) and new alternatives (including microwave-assisted extraction (MAE) as well as supercritical CO2 (SC-CO2) extraction and subcritical water extraction) The advantages and disadvantages of each technique are reported and special emphasis is given to the use of continuous subcritical water extraction which emerges as clearly advantageous over conventional techniques (by avoiding the use of organic solvents and considerably shortening the extraction time, as well as increasing the efficiency) and recent techniques, such as MAE (by increasing the efficiency) and SC-CO2 extraction (by avoiding the co-extraction of cuticular waxes and lipids and the need for a sample drying stage prior to extraction)

Journal ArticleDOI
TL;DR: Samples of olive ( Olea europaea L) leaves developed in 1993, 1994 or 1995 were collected separately from non-irrigated, mature trees at monthly intervals during 1994 (off" year) and 1995 (on' year) to determine leaf-nutrient concentration and nutrient content per leaf as mentioned in this paper.

Journal ArticleDOI
TL;DR: Results provide evidence that the PMOR system may be an interesting target to design antitumoral and anti-inflammatory drugs and the implication of a possible vanilloid receptor in calcium mobilization, but not in ROS generation is presented.
Abstract: Capsaicin is a vanilloid quinone analog that inhibits the plasma membrane electron transport (PMOR) system and induces apoptosis in transformed cells. Using a cytofluorimetric approach we have determined that capsaicin induces a rapid increase of reactive oxygen species (ROS) followed by a subsequent disruption of the transmembrane mitochondrial potential (DeltaPsim) and DNA nuclear loss in transformed cell lines and in mitogen activated human T cells. This apoptotic pathway is biochemically different from the typical one induced by either ceramide or edelfosine where, in our system, the DeltaPsim dissipation precedes the generation of reactive oxygen species. Neither production of ROS nor apoptosis was found in capsaicin-treated resting T cells where the activity of the PMOR system is minimal when compared with mitogen activated or transformed T cells. Capsaicin also induces Ca2+ mobilization in activated but not in resting T cells. However, preincubation of cells with BAPTA-AM, which chelate cytosolic free calcium, did not prevent ROS generation or apoptosis induced by capsaicin, suggesting that ROS generation in capsaicin treated cells is not a consequence of calcium signaling and that the apoptotic pathway may be separated from the one that mobilizes calcium. Moreover, we present data for the implication of a possible vanilloid receptor in calcium mobilization, but not in ROS generation. These results provide evidence that the PMOR system may be an interesting target to design antitumoral and anti-inflammatory drugs.

Journal ArticleDOI
TL;DR: The CSWE method is quicker, provides a more valuable essential oil (with higher amounts of oxygenated compounds and no significant presence of terpenes) and allows substantial savings of costs, in terms both of energy and plant material.

Journal ArticleDOI
TL;DR: In this paper, the palladium-supported catalysts were used for the liquid-phase hydrodechlorination of chlorobenzene with molecular hydrogen in the presence of chloride ions.

Journal ArticleDOI
TL;DR: Hexaploid tritordeum is the fertile amphiploid between Hordeum chilense and durum wheat, and could be useful as an additional source of genetic variability for wheat processing (pasta and bread) quality by means of using tritordum as the bridge species.

Journal ArticleDOI
TL;DR: Complex techniques providing radical stent reconstruction of the bifurcation seems to provide no advantages over the simpler stent jail followed by ostial side branch balloon dilation.
Abstract: Coronary lesions located in major bifurcations constitute a challenge for the use of stents. Although the occlusion of a side branch covered by a stent is infrequent, the maintenance of a patent, stenosis-free bifurcation may result in a complex procedure. Between September 1994 and April 1998, 70 patients were treated by stent implantation for coronary bifurcation stenosis. The side branch always had a diameter >2 mm. The pairs of treated arteries were: left anterior descending (LAD)/diagonal artery in 32 patients, circumflex/obtuse marginal in 26, right coronary/posterior descending artery in 5, and LAD/circumflex in 7. We applied 2 different techniques of stent implantation: (1) deployment of 1 stent in the parent vessel covering the takeoff of the side branch and subsequent angioplasty of the side branch across the metallic structure (group A, n = 47 patients), and (2) implantation of 1 stent at the ostium of the side branch and complete reconstruction of the entire bifurcation with additional implantation of 1 or 2 stents at the parent vessel (group B, n = 23 patients). There were no significant differences between groups at baseline variables. Procedural success was similar in both groups: 42 (89%) in group A versus 21 (91%) in group B. However, major cardiac events at 18 months follow-up were higher in group B (event-free probability 44% vs 75%, p <0.05). Selected patients with coronary stenosis at major bifurcations can be treated with an acceptable rate of primary and late success. Complex techniques providing radical stent reconstruction of the bifurcation seems to provide no advantages over the simpler stent jail followed by ostial side branch balloon dilation.

Journal ArticleDOI
TL;DR: In this article, the crystallization of ferrihydrite prepared by hydrolysis of Fe(NO3)3 solutions containing phosphate was investigated at different pH (3-9), temperatures (298, 323, and 373 K), and initial P/Fe atomic ratios for periods to 730 d.
Abstract: We investigated the crystallization of ferrihydrite prepared by hydrolysis of Fe(NO3)3 solutions containing phosphate. Crystallization was studied at different pH (3-9), temperatures (298, 323, and 373 K), and initial P/Fe atomic ratios for periods to 730 d. Generally, crystallization was inhibited or only poorly crystallized lepidocrocite was formed at P/Fe > 2.5%. Phosphate favored the formation of hematite over goethite at all temperatures for most of the pH and P/Fe ranges investigated. This result is consistent with a model in which phosphate acts as a template for hematite formation, in analogy with other anions, such as oxalate. However, goethite was preferentially formed at alkaline pH and P/Fe > 1%, probably because high phosphate concentration resulted in a large increase in the negative charge of the ferrihydrite particles. This resulted in turn in less aggregation, a process that is known to precede dehydration to hematite. Phosphate greatly influenced the morphology of hematite and goethite. Hematite was often ellipsoidal or spindle-shaped. Twinned goethite crystals with a hematite core were formed at alkaline pH at P/Fe > 1%. Both hematite and goethite particles incorporated phosphate in an occluded form not desorbable by repeated alkali treatments.

Journal ArticleDOI
TL;DR: Hypocotyls of kidney beans (Phaseolus vulgaris L.) accumulated ascorbate after preincubation with a number of possible precursors, mainly L-galactono-gamma-lactone (L-GL), suggesting that a membrane-intrinsic protein is responsible for the asCorbic acid biosynthetic activity.
Abstract: Hypocotyls of kidney beans (Phaseolus vulgaris L.) accumulated ascorbate after preincubation with a number of possible precursors, mainly L-galactono-gamma-lactone (L-GL) and L-gulono-gamma-lactone. The increase in the intracellular ascorbate concentration was parallel to the high stimulation of the L-GL dehydrogenase (L-GLD) activity measured in vitro using L-GL as a substrate and cytochrome c as an electron acceptor. Cell fractionation using a continuous linear Percoll gradient demonstrated that L-GLD is associated with mitochondria; therefore, pure mitochondria were isolated and subjected to detergent treatment to separate soluble from membrane-linked proteins. L-GLD activity was mainly associated with the detergent phase, suggesting that a membrane-intrinsic protein is responsible for the ascorbic acid biosynthetic activity. Subfractionation of mitochondria demonstrated that L-GLD is located at the inner membrane.

Journal ArticleDOI
TL;DR: Results suggest that ethylene is involved in the regulation of Fe-deficiency stress responses by Strategy I plants.

Journal ArticleDOI
TL;DR: In different areas of Extremadura, Western Spain, soil samples were taken at the bottom of holm oak trees that were showing decline symptoms, and P. chinnamomi was consistently isolated from their roots, indicating that this fungus is the causal agent ofholm oak decline.
Abstract: Summary In different areas of Extremadura, Western Spain, soil samples were taken at the bottom of holm oak (Quercus ilex) trees that were showing decline symptoms. Half of each sample was sterilized, and acorns were sown in both sterilized and nonsterilized soil samples. The resulting seedlings were used as baits for the isolation of fungi. Seedlings growing on the natural, nonsterilized substrate were characterized by having a lower vegetative growth than the ones growing on the sterilized soil samples, and most of them died. Phytophthora dnnamomi was consistently isolated from their roots. Fusarium oxysporum was also isolated as well as different species of Pythium, although to a lesser extent. Pathogenicity tests were performed on holm oak seedlings with five different isolates of P. chinnamomi, with F. oxysporum, Pythium and with a mixture of the three fungi. All the inoculated seedlings with P. chinnamomi developed root rot and grew slowly, and 35.7% of them died up to the end of the experiments. P. chinnamomi was consistently isolated from their roots, indicating that this fungus is the causal agent of holm oak decline. However, F. oxysporum caused similar symptoms on oak seedlings as P. chinnamomi, and was isolated also from the roots, although its frequency was lower than that of. P. cinnamomi.

Journal ArticleDOI
TL;DR: P phenotypic and functional alterations can be shown in NK cells in healthy aging and these changes are compatible with the expansion of a mature NK subset.

Journal ArticleDOI
TL;DR: In this article, three doped spinels of formula LiM 0.2 Mn 1.8 O 4 (M=Cr, Co) and LiTi 0.19 Mn 2.6 O 4.76 O 4 were prepared by using a sol-gel method involving Mn(acac) 3, Cr(acAC) 3, [Ti(acc) 3 ] 2 [TiCl 6 ] and Li 2 CO 3 as precursors and propionic acid as chelating agent.

Journal ArticleDOI
TL;DR: It is suggested that the MHC isoform is associated with phenotypic differences in contractile, metabolic and size properties of muscle fibre types of presumed homogeneous MHC content.
Abstract: Myofibrillar ATPase (mATPase), succinate dehydrogenase (SDH) and α-glycerophosphate dehydrogenase (GPD) activities and cross-sectional area (CSA) were measured in fibres of rat medial gastrocnemius muscle using quantitative histochemistry. The same fibres were typed immunohistochemically using monoclonal antibodies specific to selected myosin heavy chain (MHC) isoforms. The values of mATPase, SDH, GPD and CSA formed a continuum, but significant differences in mean values were observed among fibre types of presumed homogeneous MHC content. Type I fibres had the lowest mATPase activity, followed in rank order by type IIA type I>type IIB. The mean GPD activity was consistently ranked according to fibre type such that type IIB>type IID/X >type IIA>type I. Type IIA fibres were the smallest, type IIB fibres were the largest and types I and IID/X were of intermediate size. Significant interrelationships between mATPase, SDH, GPD and CSA values were found on a fibre-to-fibre basis. Consequently, discrimination of fibres according to their MHC content was possible on the basis of their mATPase, SDH, GPD and CSA profiles. These intrafibre interrelationships suggest that the MHC isoform is associated with phenotypic differences in contractile, metabolic and size properties of muscle fibre types.

Journal ArticleDOI
TL;DR: In this article, a simple model was proposed to examine the compatibility of agricultural and environmental objectives in acid sandy soils in a temperate humid climate, based on several assumptions regarding reversible and irreversible P sorption by P-reactive soil compounds (mainly poorly crystalline Fe and Al oxides).
Abstract: The sound management of agricultural soils that are heavily loaded with phosphorus (P) involves minimizing the losses of P responsible for eutrophication of surface waters, while ensuring enough P for crops. This paper describes a simple model to examine the compatibility of these two objectives in acid sandy soils in a temperate humid climate. The model is based on several assumptions regarding reversible and irreversible P sorption by P-reactive soil compounds (mainly poorly crystalline Fe and Al oxides) and release of P to water (water-P test). Model inputs are amount of P leached, P uptake by crops, and contents of poorly crystalline Fe and Al oxides in soil. The model predicts that reducing the amount of leached P to what is environmentally acceptable (e.g. 0.44 kg P ha1 year1, equivalent to 1 kg P2O5 ha1 year1) results in the long run in available soil P test values below target concentrations for optimum crop growth. When the amount of leached P is set to a fixed value the model predicts that soils with large contents of Fe and Al oxides can maintain the initial soil P test values for longer periods than other soils. The content in available P decreases if fertilizer P is applied to the soil at a rate equal to P uptake by crops. These results stress the difficulties involved in trying to make agricultural and environmental needs compatible in acid sandy soils.

Journal ArticleDOI
TL;DR: Induction by H2O2 induced expression of the genes controlled by OxyR, including the oxyR locus, which was a remarkably rapid and reversible process that took place in an OxyR-dependent and sigmaS-independent manner.
Abstract: Simultaneous expression of seven genes in Escherichia coli was measured by a reverse transcription-multiplex PCR fluorescence procedure. Genes studied were (i) oxyR (transcriptional regulator); (ii) katG, dps, gorA, and ahpCF (controlled by OxyR); (iii) sodA (controlled by SoxRS); and (iv) trxA (not related to OxyR or SoxRS). Except for trxA, transcription of all genes was activated during the course of growth of wild-type bacteria, though notable variations were observed with respect to both the time and extent of activation. Whereas oxyR, katG, dps, and gorA were activated during exponential growth, ahpCF and sodA were stimulated in stationary phase. Maximal induction ranged from 4.6- to 86.5-fold, for gorA and dps, respectively. Treatment with H2O2 stimulated expression of the genes (katG, dps, ahpCF, and gorA) previously identified as members of the OxyR regulon, except for oxyR itself. Induction by H2O2 was a remarkably rapid and reversible process that took place in an OxyR-dependent and sigmaS-independent manner. NaCl induced expression of the genes controlled by OxyR, including the oxyR locus. This transcriptional up-regulation was preserved in a strain with the DeltaoxyR::kan mutation, but it was abolished (ahpCF) or significantly reduced (oxyR and dps) in a strain with the rpoS::Tn10 mutation, potentially reflecting positive transcriptional regulation of the oxyR regulon by sigmaS. Expression of trxA was not increased either by H2O2 stress or by a shift to high-osmolarity conditions.

Journal ArticleDOI
TL;DR: The heritabilities and genetic correlations of these traits were estimated using a BLUP Animal model with REML methodology, which agrees with the fact that they are the most subjective and complex features being closely tied to the behaviour variables.

Journal ArticleDOI
TL;DR: These integrated methods for the analysis of MHCs at the protein level demonstrate that equine skeletal muscle does not express the MHC-IIB, so type II fibres have been misclassified in numerous previous studies based upon the very traditional mATPase histochemistry.
Abstract: Combined methodologies of enzyme-linked immunosorbent assay (ELISA), sodium dodecyl sulphate polyacrilamide gel electrophoresis (SDS-PAGE), immunoblotting, traditional myofibrillar ATPase (mATPase) histochemistry and immunocytochemistry of whole biopsied samples were used to study myosin heavy chain (MHC) isoforms in the equine gluteus medius muscle. The ELISA technique allowed the quantification of the three MHC isoforms known to be present in different horse muscles: slow (MHC-I) and two fast (termed MHC-IIA and MCH-IIX). The SDS-PAGE method resolved MHCs in three bands: MHC-I, MHC-IIX and MHC-IIA from the fastest to the slowest migrating band and a quantification by densitometry for each MHC isoform was also possible. The identity of these three MHCs was confirmed by immunoblots with specific monoclonal antibodies. Five fibre types were defined immunohistochemically according to their MHC content: I, I + IIA, IIA, the hybrid IIAX and IIX. When quantitative data obtained with the four different methodologies were combined and compared, they were consistent and, when considered together, showed significant correlation. Nevertheless, the percentage of MHC-IIA histochemically derived was underestimated, while that of MHC-IIX was overestimated in comparison with the immunocytochemical determination of these MHC isoforms. The percentage of MHC-I obtained by ELISA technique was underestimated. In short, these integrated methods for the analysis of MHCs at the protein level demonstrate that equine skeletal muscle does not express the MHC-IIB, so type II fibres have been misclassified in numerous previous studies based upon the vary traditional mATPase histochemistry. They also offer new prospects for muscle fibre typing in equine experimental studies and veterinary medicine.