Showing papers by "University of Córdoba (Spain) published in 1997"
TL;DR: The Wiskott-Aldrich syndrome (WAS) is a severe immunodeficiency and platelet deficiency disease arising from mutation(s) in the WASP gene, which in normal cells encodes an intracellular protein able to interact with other proteins relevant to the control of cytoskeleton organization as discussed by the authors.
192 citations
TL;DR: The results obtained seem to corroborate previous findings in the literature which conjecture that the actual behaviour of farmers cannot be explained by the optimization of a single objective but by a compromise between multiple objectives.
171 citations
TL;DR: It is proposed that the ripe fruit expression of this strawberry gene with similarity to pectate lyases could be related to cell wall pectin degradation contributing to strawberry fruit softening.
Abstract: A strawberry fruit cDNA showing sequence similarity to higher-plant pectate lyase genes has been isolated by differential screening of a strawberry fruit cDNA subtractive library. The cDNA contains a 396 amino acids open reading frame corresponding to a 44.8 kDa protein. The transcript is predominantly expressed in ripe fruits and was not detected at high levels in any other plant tissues. The removal of the achenes from unripe green fruits induced the expression of this putative pectate lyase gene. In common with other ripening related genes in strawberry, this induction was partially inhibited by treatment of de-achened fruit with the auxin NAA. Southern blot analysis of genomic DNA indicates that in strawberry there is more than one putative pectate lyase gene. We propose that the ripe fruit expression of this strawberry gene with similarity to pectate lyases could be related to cell wall pectin degradation contributing to strawberry fruit softening.
169 citations
TL;DR: In this article, the potential of the oxidation of various carcinogenic aromatic amines by Fenton's reagent [Fe(II) + H2O2] for liquid waste treatments was assessed.
164 citations
TL;DR: The data show that leptin markedly influences LH secretion and the estrous cycle in the female rat and an impairment of reproductive function is shown.
Abstract: Recent data indicate that leptin may well play an important regulatory role in the hypothalamo-pituitary-gonadal axis. In order to further unravel the mechanisms by which leptin acts, we have studied the effect of treatment (8 days) of leptin antiserum (5 microl daily; i.c.v.) on LH pulsatility and estrous cycle in adult female rats. The administration of leptin antiserum led to a marked decrease in LH pulsatility as assessed by the area under the curve (13.5 +/- 4.7 ng/ml) in comparison to rats treated with normal rabbit serum (114 f 53 ng/ml; p < 0.01). Furthermore, rats treated with leptin antiserum showed an impairment of reproductive function as shown by the fact that all rats remained in anestrus. In conclusion, these data show that leptin markedly influences LH secretion and the estrous cycle in the female rat.
163 citations
TL;DR: In this paper, the structural characterization of boron-doped LiCoO2 was carried out using low-spin Ni3+probes and showed a distorted tetrahedral coordination.
140 citations
TL;DR: This study showed a prevalence of thrombocytopenia of 23.4% in APS patients, and these patients did not present any significant clinical or serological features that distinguish them from those patients without throm bocy topenia.
Abstract: OBJECTIVE—To determine the prevalence of thrombocytopenia in a group of patients suffering from the antiphospholipid syndrome (APS) and to investigate whether these patients may have any particular clinical or serological features.
METHODS—Retrospective analysis. A group of 171 APS patients seen in our department were studied for the presence of thrombocytopenia. Clinical and serological features of these patients were analysed by standard methods and each of them was correlated to the presence of thrombocytopenia and compared with those found in the group without thrombocytopenia.
RESULTS—Each of the patients studied had a minimum of three platelet counts during the follow up period. Forty (23.4%) were found to have thrombocytopenia; 13 with persistently low and 27 patients with intermittently low platelet counts. There were no statistically significant differences in sex, age, disease duration or diagnosis when compared with the group of APS patients without thrombocytopenia. Thrombocytopenia was associated with thrombosis in 18, with miscarriages in five, and with both of these features in 13 patients. It was the only manifestation of the APS in four patients. All patients had persistently positive tests for antiphospholipid antibodies concomitantly with the low platelet counts. No significant association was found between the presence of thrombocytopenia and clinical or serological manifestations in APS patients.
CONCLUSION—This study showed a prevalence of thrombocytopenia of 23.4% in APS. These patients did not present any significant clinical or serological features that distinguish them from those patients without thrombocytopenia.
133 citations
TL;DR: The effects of external treatments with different N sources showed that the regulation of the Nrt2 gene(s) is very similar to that reported for nitrate reduct enzyme and nitrite reductase genes: their expression was strongly induced by nitrate but was repressed when reduced forms of N were supplied to the roots.
Abstract: A family of high-affinity nitrate transporters has been identified in Aspergillus nidulans and Chlamydomonas reinhardtii, and recently homologues of this family have been cloned from a higher plant (barley). Based on six of the peptide sequences most strongly conserved between the barley and C. reinhardtii polypeptides, a set of degenerate primers was designed to permit amplification of the corresponding genes from other plant species. The utility of these primers was demonstrated by RT-PCR with cDNA made from poly(A)+ RNA from barley, C. reinhardtii and Nicotiana plumbaginifolia. A PCR fragment amplified from N. plumbaginifolia was used as probe to isolate a full-length cDNA clone which encodes a protein, NRT2;1Np, that is closely related to the previously isolated crnA homologue from barley. Genomic Southern blots indicated that there are only 1 or 2 members of the Nrt2 gene family in N. plumbaginifolia. Northern blotting showed that the Nrt2 transcripts are most strongly expressed in roots. The effects of external treatments with different N sources showed that the regulation of the Nrt2 gene(s) is very similar to that reported for nitrate reductase and nitrite reductase genes: their expression was strongly induced by nitrate but was repressed when reduced forms of N were supplied to the roots.
127 citations
TL;DR: Monitoring the evolution of spoilage organisms in a mixed salad of red cabbage, lettuce and carrot stored at 4 degrees C, 10 degrees C and 15 degrees C established a theoretical shelf-life time as a function of temperature, and lactic acid bacteria at levels of 10(6) cfu/g appeared to be related to both spoilage and theoretically-predicted shelf- life values.
115 citations
TL;DR: The antioxidant potential of the reduced coenzyme Q is now taken on a new significance in the evidence that the reduced quinone can act to maintain tocopherol in the reduced state in membranes and ascorbate reduced both inside and outside the cell.
108 citations
TL;DR: Among the liquid solvents studies, only acetone provided comparable results (73% recovery relative to SC-CO(2) extraction); however, it required decoloration with active carbon prior to HPLC analysis.
Abstract: Supercritical fluid extraction (SFE) and liquid solvent sonication, in combination with two different sample treatments, were compared for the extraction of natural antioxidants from rosemary leaves. Dried, ground, and sieved rosemary leaves (20 mg) were subjected to SFE with CO2 at 355 bar at 100 °C (CO2 density 0.72 g/mL) for 20 min at a liquid flow rate of 4 mL/min. The analytes were concentrated on an ODS trap and subsequently eluted with acetone. Antioxidants in the SF and liquid solvent extract were analyzed by HPLC. Compounds of known antioxidant activity such as carnosol, carnosic acid, and methyl carnosate were identified by mass spectrometry of the HPLC fractions collected. Freezing and grinding the samples in liquid nitrogen resulted in decreased carnosic acid recoveries. Supercritical CO2 extraction provided the highest recovery of carnosic acid from rosemary leaves (35.7 mg/g), the lowest relative standard deviation (4.4%), and the cleanest extractno cleanup prior to HPLC was required. Among ...
TL;DR: In this article, a low-pressure hydrogenator was used to reduce cathedral in the liquid phase by using catalysts consisting of palladium supported on a mixed 80:20 SiO2/AlPO4 system and sepiolite from Vallecas (Madrid, Spain).
TL;DR: Ergosterol and oleic acid added to the musts generally increased the levels of the aroma compounds in wine compared to those obtained in anaerobic conditions.
Abstract: Changes in aroma compounds synthesised from grape must during fermentation carried out by Saccharomyces cerevisiae, in semi-aerobic, anaerobic, short aeration conditions and after adding ergosterol and oleic acid to the must were studied. The biosynthesis of these aroma compounds was strongly dependent on the fermentation conditions and on the growth of the yeast. Ethanol, isoamyl alcohols, isobutyl alcohol, phenethyl alcohol and isoamyl, butyl and hexyl acetates were produced in greater concentrations in semiaerobic conditions, mainly during cellular growth. 1-Butanol and 1-pentanol were produced in greater levels in anaerobic conditions, when cellular growth was lower. Ergosterol and oleic acid added to the musts generally increased the levels of the aroma compounds in wine compared to those obtained in anaerobic conditions. © 1997 SCI.
TL;DR: The full chromosomal karyotype of six enological Saccharomyces cerevisiae strains used for fermentation and biological ageing of sherry‐type wines was studied, and the results indicate the presence of two, three or four copies of a chromosome in the industrial strains examined, and thus confirm that aneuploidy/polyploidsy is not uncommon in these strains.
Abstract: The full chromosomal karyotype of six enological Saccharomyces cerevisiae strains used for fermentation and biological ageing of sherry-type wines was studied. A genetic method based on the analysis of segregation frequencies of auxotrophic markers, among random spore progeny of hybrids, constructed between laboratory and industrial wine strains (Bakalinsky and Snow, 1990) was used. This method was combined with the analysis of strains by pulsed-field gel electrophoresis. The results obtained clearly indicate the presence of two, three or four copies of a chromosome in the industrial strains examined, and thus confirm that aneuploidy/polyploidy is not uncommon in these strains. In all strains examined, chromosome XIII polysomy is observed. This chromosome contains theADH2 and ADH3 loci, that code for the ADHII and ADHIII isoenzymes of alcohol dehydrogenase, which are involved in ethanol oxidative utilization during biological ageing of wines. Tetrad analysis for the ‘flor formation’ character suggests two possibilities: this character is either regulated by at least a digenic system, or by only one gene present on a chromosome which is, at least, disomic. key words—Saccharomyces cerevisiae; relative ploidy; chromosomes; aneuploidy; flor yeast
TL;DR: The idea that when the plasma membrane barrier fails, bcl-2 protein would be required to prevent cell death is supported to protect lipids from oxidative stress and subsequent apoptosis.
TL;DR: Though both microorganisms behave in a similar way, G. candidum seems to be slightly better for removing phenols from vinasse than Aspergillus terreus, which is aimed at finding the most suitable microorganism for removing Phenolic compounds.
TL;DR: The data support the idea that besides intracellular cytochrome b5-dependent ascorbate regeneration, the extracellular stabilization of asCorbate is mediated by CoQ10 and its NADH-dependent reductase.
Abstract: Plasma membranes isolated from K562 cells contain an NADH-ascorbate free radical reductase activity and intact cells show the capacity to reduce the rate of chemical oxidation of ascorbate leading to its stabilization at the extracellular space. Both activities are stimulated by CoQ10 and inhibited by capsaicin and dicumarol. A 34-kDa protein (p34) isolated from pig liver plasma membrane, displaying NADH-CoQ10 reductase activity and its internal sequence being identical to cytochrome b5 reductase, increases the NADH-ascorbate free radical reductase activity of K562 cells plasma membranes. Also, the incorporation of this protein into K562 cells by p34-reconstituted liposomes also increased the stabilization of ascorbate by these cells. TPA-induced differentiation of K562 cells increases ascorbate stabilization by whole cells and both NADH-ascorbate free radical reductase and CoQ10 content in isolated plasma membranes. We show here the role of CoQ10 and its NADH-dependent reductase in both plasma membrane NADH-ascorbate free radical reductase and ascorbate stabilization by K562 cells. These data support the idea that besides intracellular cytochrome b5-dependent ascorbate regeneration, the extracellular stabilization of ascorbate is mediated by CoQ10 and its NADH-dependent reductase.
TL;DR: Antioxidants effective at the plasma membrane such as Asc and alphaTOH can protect cells from oxidative damage and prevent apoptosis independent of Bcl-2 content.
TL;DR: The results confirm the involvement of free radicals in the pathogenesis of nephrotoxicity induced by AD and show the high antioxidative power of MEL and its marked effect on the prevention and suppression of this nephropathy.
Abstract: The effect of melatonin (MEL) on the nephropathy and the oxidative stress induced by a single and high dose of Adriamycin (AD) has been studied in Wistar male rats. MEL (50 microg/kg/day) was injected intraperitoneally 3 and 7 days, respectively, before and after AD injection (20 mg/kg i.p.). Trunk blood was drawn and triglycerides, total cholesterol, phospholipids, high-density lipoprotein cholesterol, urea, creatinine, total protein, lipoperoxides, and reduced glutathione (GSH) levels and catalase activity (CAT) were determined in serum. In kidney homogenates, lipoperoxides, GSH, and CAT were measured as well as total protein in urine. AD administration resulted in hyperlipidemia and high-grade proteinuria and a marked increase in serum lipoperoxides, urea, and creatinine. In the kidney, the increase in lipoperoxides was accompanied by a significant decrease of GSH and CAT. The efficiency of MEL was specially remarkable in restoring GSH, CAT, and proteinuria to the levels of controls. These results confirm the involvement of free radicals in the pathogenesis of nephrotoxicity induced by AD. Likewise, they show the high antioxidative power of MEL and its marked effect on the prevention and suppression of this nephropathy.
TL;DR: Protamine use for neutralizing circulating heparin may be safely administered immediately after stent implantation because the hospital stay after treatment was shorter in patients receiving protamine.
Abstract: Two hundred twenty-eight patients with successful coronary stent implantation were randomized either to protamine administration and femoral sheath removal (group I, n = 117) or no heparin neutralization and delayed sheath removal (group II, n = 111). The hospital stay after treatment was shorter in patients receiving protamine; therefore, protamine use for neutralizing circulating heparin may be safely administered immediately after stent implantation.
TL;DR: The presence of organochlorine pesticides in Spanish pasteurized milk were investigated and none of the samples exceeded the limit for the DDT group.
TL;DR: Results demonstrate a relationship between ubiquinone levels in the plasma membrane and the induction of serum withdrawal induced apoptosis, and ceramide accumulation, which can represent a first level of protection against oxidative damage caused by serum withdrawal.
Abstract: Serum provides cultured cells with survival factors required to maintain growth. Its withdrawal induces the development of programmed cell death. HL-60 cells were sensitive to serum removal, and an increase of lipid peroxidation and apoptosis was observed. Long-term treatment with ethidium bromide induced the mitochondria-deficient rho(o)HL-60 cell line. These cells were surprisingly more resistant to serum removal, displaying fewer apoptotic cells and lower lipid peroxidation. HL-60 cells contained less ubiquinone at the plasma membrane than rho(o)HL-60 cells. Both cell types increased plasma membrane ubiquinone in response to serum removal, although this increase was much higher in rho(o) cells. Addition of ubiquinone to both cell cultures in the absence of serum improved cell survival with decreasing lipid peroxidation and apoptosis. Ceramide was accumulated after serum removal in HL-60 but not in rho(o)HL-60 cells, and exogenous ubiquinone reduced this accumulation. These results demonstrate a relationship between ubiquinone levels in the plasma membrane and the induction of serum withdrawal-induced apoptosis, and ceramide accumulation. Thus, ubiquinone, which is a central component of the plasma membrane electron transport system, can represent a first level of protection against oxidative damage caused by serum withdrawal.
TL;DR: An automated interface for coupling flow injection (FI) systems with capillary electrophoresis (CE) has been developed and tested to combine the sample preparation capabilities of FI systems with the separation and determination provided by CE as discussed by the authors.
TL;DR: In this paper, total plant-available phosphorus (TPAP) in 12 P-rich soils from major agricultural areas of the European Union was estimated by successive cropping in pots, and compared to the amount of P extracted by different methods.
TL;DR: An overview of the different ways to accomplish pretreatment of solid samples is presented in this paper, where the use of auxiliary energies such as lyophilisation, ultrasound, microwaves and laser radiation, as well as commercial modules including simple units such as Soxhlet and more sophisticated supercritical fluid extractors, is looked at critically.
Abstract: An overview of the different ways to accomplish pretreatment of solid samples is presented. The use of 1. (a) auxiliary energies such as lyophilisation, ultrasound, microwaves and laser radiation, 2. (b) commercial modules including simple units such as Soxhlet and more sophisticated supercritical fluid extractors, and 3. (c) robotic stations working individually or coupled to other automated alternatives, is looked at critically.
TL;DR: The results suggest that both the preovulatory and the twice-daily PRL surges regulate the macrophage population in newly formed and regressing corpora lutea.
Abstract: The proliferative activity of vascular cells and the number of macrophages were studied in corpora lutea of cycling and pregnant rats after prolactin (PRL) administration or depletion with the dopaminergic agonist CB154. Pregnant rats showed a higher proliferative activity of the vascular cells in newly formed corpora lutea than did cycling rats in metestrus. When cycling rats were treated with PRL, the proliferative activity was equivalent to that of pregnant rats. Treatment of pregnant rats with CB154 decreased the proliferative activity of vascular cells to the level in cycling rats. Otherwise, the proliferative activity was not modified in cycling rats after CB154 treatment. This indicates that the increase in the proliferative activity of vascular cells in the corpus luteum of pregnancy was due to the twice-daily PRL surges induced by mating. Treatment of cycling rats with CB154 decreased the number of macrophages in both newly formed and regressing corpora lutea, whereas PRL treatment increased the number of macrophages in regressing corpora lutea. In pregnant rats, treatment with CB154 decreased the number of macrophages in both newly formed and regressing corpora lutea. These results suggest that both the preovulatory and the twice-daily PRL surges regulate the macrophage population in newly formed and regressing corpora lutea.
TL;DR: Each reproductive stock displayed its own life-history characteristics, with significant differences between mean length of reproducing females, growth rate, mean brood size, offspring size, standard fecundity and minimum length at reproduction.
Abstract: Introduced Gambusia holbrooki in a natural lagoon of southern Spain consisted of two age groups: 1992 cohort, 7-11 months old and 1993 cohort, <4 months old. In the 1992 cohort, females grew even during the gestation period at about 0.30 mm day-1. In the 1993 cohort, females displayed a high growth rate (0.55 mm day-1) and reached reproductive size in a few weeks, but stopped growing when they matured. All the 1992 cohort reproduced from mid-May to mid-June, but only 50% of the 1993 cohort reproduced, from mid-August to mid-September. Reproducing females were significantly larger in the 1992 cohort (39.8 mm) than in the 1993 one (34.8 mm). The largest 1992 females cohort had reproduced previously; the 1993 cohort had not. The mean dry weight of intra-ovarian embryos decreased to a minimum immediately before birth. These metabolic costs represented 29.8 and 31.4% of the initial weights of the 1992 and 1993 embryos, respectively. Mean dry weight of full-term embryo was significantly higher in the 1992 cohort (0.80+/-0.129 mg; 95% CL) than in the 1993 one (0.70+/-0.086 mg; 95% CL). With more females in 1992, cohort fecundity was considerably higher (number of embryos=7151; 63%) than in the 1993 (4193; 37%) cohort. The population completed two generations each year (spring and summer). The spring stock grew slower than the summer one but continued to grow during the gestation period, reaching larger final lengths, with more synchronous reproduction and clearer evidence of a second reproductive event. Each reproductive stock displayed its own life-history characteristics, with significant differences between mean length of reproducing females, growth rate, mean brood size, offspring size, standard fecundity and minimum length at reproduction.
TL;DR: Chlorophyll fluorescence and Hill reaction analysis supported the view that the mechanism of resistance to atrazine in the X biotype was modification of the target site, the DI protein, and quinclorac is not a PS II inhibiting herbicide.
Abstract: Two populations of Echinochloa crus-galli (R and I) exhibited resistance to quinclorac. Another population (X) exhibited resistance to quinclorac and atrazine. The R and I populations were collected from monocultures of rice in southern Spain. The X population was collected from maize fields subjected to the application of atrazine over several years. The susceptible (S) population of the same genus was collected from locations which had never been treated with herbicides. The quinclorac ED50 value (dose causing 50% reduction in shoot fresh weight) for the R and I biotypes were 26- and 6-fold greater than for the S biotype. The X biotype was 10 times more tolerant to quinclorac than the S biotype and also showed cross-resistance to atrazine, being 82-fold more resistant to atrazine than the R, I and S biotypes. Chlorophyll fluorescence and Hill reaction analysis supported the view that the mechanism of resistance to atrazine in the X biotype was modification of the target site, the DI protein. Quinclorac at 20 mg litre-1 did not inhibit photosynthetic electron transport in any of the test biotypes. The quinclorac I50 values (herbicide dose needed for 50% Hill reaction reduction) of the S population was over 50000-fold higher than the atrazine I50 value for the same S population, indicating that quinclorac is not a PS II inhibiting herbicide. Propanil at doses greater than 0·5 kg ha-1 controlled all the biotypes. © 1997 SCI
TL;DR: In this paper, the effects of two levels of uniformity (mean Wilkox and Swailes' uniformity coefficients of 80% and 52%) at two different levels of water supply (about 400 and 260 mm for the whole irrigation season) on cotton production were compared.
Abstract: Sprinkler irrigation systems are characterized by some degree of non-uniformity. The effect of non-uniformity on crop yield has been modelled in different ways but experimental studies are scarce. An experiment was conducted comparing the effects of two levels of uniformity (mean Wilkox and Swailes' uniformity coefficients of 80% and 52%) at two levels of water supply (about 400 and 260 mm for the whole irrigation season) on cotton production. Final yield was not affected either by uniformity or by the amount of water supplied. Vegetative growth was higher in the full irrigation treatments. Maximum leaf area index did not differ statistically between uniformity treatments. The lack of differences was attributed to the curvilinear shape of the yield function and to the dampening of the variations in applied water in the soil, as the coefficient of variation in applied water was more than twice the coefficient of variation of infiltrated water. These results suggest that non-uniformity of conventional sprinkler irrigation has a lower impact on cotton crop performance than expected from previous simulation studies.
TL;DR: In this paper, changes in absorbance (A420, A280) and phenolic compounds during browning of white wines from Pedro Ximenez and Baladi grapes were studied.