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C Royo

Publications and source records attributed to C Royo.

At least 19 recordsLinked to original sources
PubMed2006

Monitoring sedation in critically ill patients: bispectral index, Ramsay and observer scales.

BACKGROUND AND OBJECTIVE: Sedation is commonly required by critically ill patients and inadequate sedation may be hazardous. Traditionally, subjective scales have been used for monitoring sedation. Bispectral index has been proposed, although its utility in the intensive care unit is debated. Our aim was to evaluate the depth of sedation in intubated surgical critically ill patients by means of two sedation scales (Ramsay and Observer's Assessment of Alertness and Sedation) and bispectral index. METHODS: Sedation was assessed prospectively in 50 postoperative intubated patients requiring at least 24 h of sedation (35 propofol, 15 midazolam/fentanyl), every 8 h for a 24 -h period. The bispectral index value recorded was the mean value obtained during a 10-min observation period, whenever the quality signal index was above 75% and the electromyographic signal was below 25%. RESULTS: Most of the patients (78%) were oversedated (bispectral index < 60). The three sedation scores (global data) correlated significantly (P < 0.001). This correlation was lost in the midazolam group in which the patients were also significantly more sedated than the propofol group (P = 0.001). The correlation between the bispectral index and the scales in the midazolam group reappeared when the measurements with a Ramsay = 6 or an Observer's Assessment of Alertness and Sedation = 1 were excluded. CONCLUSIONS: Sedation should be monitored routinely in intensive care units. The Ramsay and the Observer's Assessment of Alertness and Sedation scales showed equal efficacy. Bispectral index might prove useful for discriminating between deeper levels of sedation.

Aged↗
PubMed2005

Development of a citrus genome-wide EST collection and cDNA microarray as resources for genomic studies.

A functional genomics project has been initiated to approach the molecular characterization of the main biological and agronomical traits of citrus. As a key part of this project, a citrus EST collection has been generated from 25 cDNA libraries covering different tissues, developmental stages and stress conditions. The collection includes a total of 22,635 high-quality ESTs, grouped in 11,836 putative unigenes, which represent at least one third of the estimated number of genes in the citrus genome. Functional annotation of unigenes which have Arabidopsis orthologues (68% of all unigenes) revealed gene representation in every major functional category, suggesting that a genome-wide EST collection was obtained. A Citrus clementina Hort. ex Tan. cv. Clemenules genomic library, that will contribute to further characterization of relevant genes, has also been constructed. To initiate the analysis of citrus transcriptome, we have developed a cDNA microarray containing 12,672 probes corresponding to 6875 putative unigenes of the collection. Technical characterization of the microarray showed high intra- and inter-array reproducibility, as well as a good range of sensitivity. We have also validated gene expression data achieved with this microarray through an independent technique such as RNA gel blot analysis.

Citrus↗
PubMed2005

Pressure-volume curve variations after a recruitment manoeuvre in acute lung injury/ARDS patients: implications for the understanding of the inflection points of the curve.

BACKGROUND AND OBJECTIVE: Although the pressure-volume (P-V) curve has been proposed in the management of mechanically ventilated patients, its interpretation remains unclear. Our aim has been to study the variations of the P-V curve after a recruitment manoeuvre (RM). Our hypothesis was that the lower inflection point (LIP) represents the presence of compressive atelectases, so it should not change after lung recruitment, while the upper inflection point (UIP) reflects reabsorptive atelectases, and an effective recruitment should result in changes at this level. METHODS: Two P-V curves (quasi-static method) separated by an RM (40 cmH2O, two consecutive manoeuvres) were plotted in 35 postoperative patients with criteria of acute lung injury/acute respiratory distress syndrome (ARDS). LIP, UIP and expiratory inflection point (EIP) were defined as the first point where the curve consistently starts to separate from the line. RESULTS: One to six measurements were obtained per patient (73 procedures). Neither the lower nor the EIPs varied significantly after the RM (P = 0.11 and 0.35, respectively). An UIP was observed in 18 curves (25%) before the RM and disappeared on nine occasions after the recruitment. Similar results were obtained when first measurements only were analysed, and when the cause (pulmonary vs. extrapulmonary), severity of lung injury or duration of mechanical ventilation at first measurement were studied. CONCLUSIONS: An RM does not modify the LIP significantly, but induces the disappearance of the UIP in 50% of the cases in which this point is found.

Aged↗
PubMed2003

Adjusting positive end-expiratory pressure and tidal volume in acute respiratory distress syndrome according to the pressure-volume curve.

BACKGROUND: Management of acute respiratory distress syndrome (ARDS) patients implies the selection of the adequate ventilatory parameters, essentially PEEP and tidal volume (Vt), to prevent ventilator-induced lung injury. These parameters should be reset as the lung injury evolves. Among the different methods proposed for the adjustment of the ventilator, the measurement of the P-V curve has emerged as a useful, although debated, tool. Our aim has been to study the relationship between the different inflection points of the P-V curve in ARDS patients, and to assess the changes in the empiric PEEP and Vt (PEEP(emp), V(temp) following its use. METHODS: P-V curves were measured in 27 patients (lung injury score [LIS] >or= 2, 69 measurements) by means of the low-flow continuous inflation method. RESULTS: A lower inflection point (LIP) was found in all patients and, although it correlated with the PEEP(emp), there was only a fair concordance, so the PEEP was modified in 80% of the cases. The expiratory inflection point (EIP) was significantly lower than the LIP (6.3 +/- 1.7 vs. 8.1 +/- 3.2, P = 0.008). An upper inflection point was observed in 16 measurements (23%) and the Vt was reset in 20% of the cases. Both PEEP and Vt were readjusted on 10 occasions (14%). Only the EIP was significantly higher on the first 3 days of mechanical ventilation. The LIS was correlated with all the inflection points. There were no differences for any parameter independent of the cause of the ARDS (pulmonary/extrapulmonary). CONCLUSIONS: The quasi-static measurement of the P-V curve is a simple method, easy to interpret, for objective adjustment of the ventilatory parameters in ARDS patients as the lung injury evolves. The implementation of this strategy may vary the empiric clinical practice. The role of the EIP for the evaluation of the severity of lung injury deserves further investigation.

Acute Disease↗
PubMed2002

Plant breeding and drought in C3 cereals: what should we breed for?

Drought is the main abiotic constraint on cereal yield. Analysing physiological determinants of yield responses to water may help in breeding for higher yield and stability under drought conditions. The traits to select (either for stress escape, avoidance or tolerance) and the framework where breeding for drought stress is addressed will depend on the level and timing of stress in the targeted area. If the stress is severe, breeding under stress-free conditions may be unsuccessful and traits that confer survival may become a priority. However, selecting for yield itself under stress-alleviated conditions appears to produce superior cultivars, not only for optimum environments, but also for those characterized by frequent mild and moderate stress conditions. This implies that broad avoidance/tolerance to mild-moderate stresses is given by constitutive traits also expressed under stress-free conditions. In this paper, we focus on physiological traits that contribute to improved productivity under mild-moderate drought. Increased crop performance may be achieved through improvements in water use, water-use efficiency and harvest index. The first factor is relevant when soil water remains available at maturity or when deep-rooted genotypes access water in the soil profile that is not normally available; the two latter conditions become more important when all available water is exhausted by the end of the crop cycle. Independent of the mechanism operating, a canopy able to use more water than another would have more open stomata and therefore higher canopy temperature depression, and 13C discrimination (delta13C) in plant matter. The same traits would also seem to be relevant when breeding for hot, irrigated environments. Where additional water is not available to the crop, higher water-use efficiency (WUE) appears to be an alternative strategy to improve crop performance. In this context delta13C constitutes a simple but reliable measure of WUE. However, in contrast to lines performing better because of increased access to water, lines producing greater biomass due to superior WUE will have lower delta13C values. WUE may be modified not only through a decrease in stomatal conductance, but also through an increase in photosynthetic capacity. Harvest index is strongly reduced by terminal drought (i.e. drought during grain filling). Thus, phenological traits increasing the relative amount of water used during grain filling, or adjusting the crop cycle to the seasonal pattern of rainfall may be useful. Augmenting the contribution of carbohydrate reserves accumulated during vegetative growth to grain filling may also be worthwhile in harsh environmcnts. Alternatively, extending the duration of stem elongation without changing the timing of anthesis would increase the number of grains per spike and the harvest index without changing the amount of water utilized by the crop.

Acclimatization↗
PubMed1998

Effect of ranitidine on gastric intramucosal pH in critically ill patients.

OBJECTIVE: To determine whether ranitidine a) increases the values of gastric intramucosal pH (pHi) in critically ill patients, as determined by tonometry; b) reduces the variability of these measurements. DESIGN: Prospective, double blind, randomized, placebo-controlled study. SETTING: General Intensive Care Unit of a teaching hospital. PATIENTS: Twenty-five critically ill, mechanically ventilated patients requiring arterial catheter and nasogastric tube. INTERVENTIONS: Tonometer placement; blind, random administration of intravenous ranitidine (50 mg) or placebo. MEASUREMENTS AND MAIN RESULTS: Tonometer saline PCO2 (PCO2i), arterial blood gases, gastric juice pH and pHi were determined immediately before, and 2, 4, 6 and 8 h after, ranitidine (12 patients) or placebo (13 patients). Ranitidine significantly increased gastric juice pH, but did not affect PCO2i or pHi; pHi was 7.34 +/- 0.14 before ranitidine, and 7.30 +/- 0.12, 7.31 +/- 0.11, 7.31 +/- 0.14 and 7.31 +/- 0.12-2, 4, 6 and 8 h, respectively, after ranitidine administration (p = 0.55). Ranitidine did not modify the coefficients of variation of PCO2i or pHi, either. No significant changes in gastric juice pH, PCO2i or pHi were observed in the placebo group. CONCLUSIONS: In critically ill patients, ranitidine has no effect on pHi values, and does not increase the reproducibility of pHi measurements.

APACHE↗
PubMed1997

Effect of sucralfate on gastric intramucosal pH in critically ill patients.

OBJECTIVE: To determine whether sucralfate administration affects the tonometric measurement of gastric intramucosal pH (pHi). DESIGN: Non-randomized observational study. SETTING: General intensive care unit of a teaching hospital. PATIENTS: Twenty critically ill, mechanically ventilated, consecutively admitted patients requiring an arterial catheter and nasogastric tube. INTERVENTIONS: Tonometer placement and sucralfate administration. MEASUREMENTS AND MAIN RESULTS: We simultaneously determined tonometer saline PCO2 (PCO2i), arterial blood gases, pH of gastric juice and pHi. These parameters were evaluated immediately before sucralfate administration, and 2 h and 4 h after. We did not detect any change in either PCO2i or pHi after sucralfate administration (PCO2i: basal 6.4 +/- 1.7, 2 h 6.3 +/- 1.7, 4 h 6.3 +/- 1.7; pHi: basal 7.35 +/- 0.13, 2 h 7.36 +/- 0.12, 4 h 7.36 +/- 0.12). CONCLUSIONS: Sucralfate does not affect the tonometric measurement of PCO2i and pHi.

Adult↗
PubMed1992

Carbon isotope ratios in ear parts of triticale : influence of grain filling.

Four triticale (xTriticosecale Wittmack) genotypes were grown under rainfed conditions with limited irrigation support in Lleida in northeast Spain. For each variety, samples consisting of 10 tillers with half-sterilized spikes were taken three times from anthesis to maturity. Carbon isotope ratios (delta(13)C) were then determined in water extracts from ear bracts (glumes, paleas, and lemmas), awns and flag leaves, and in powdered kernels. For the half-sterilized spikes, carbon isotope analysis was carried out separately in bracts and awns from fertile and nonfertile spikelets. The delta(13)C in the water-soluble fraction of awns, glumes, and glumells from fruitless spikelets was significantly higher than that from fertile spikelets sampled at mid-grain filling. Differences in delta(13)C among sterile and fertile spikelets were not significant in samples taken a few days after anthesis or at maturity. These results are in accordance with some degree of refixation by awns and ear bracts of the CO(2) respired by grains during grain filling. There was progressively higher delta(13)C from flag leaf blades to awns, glumes, and glumells. This variation in delta(13)C along plant parts may be caused by differences in the ratio of assimilation rate to CO(2)-diffusive conductance. Values of delta(13)C of mature kernels were between the values at anthesis and mid-grain filling for the water-soluble fraction of flag leaves and inner bracts and were fairly similar to those of glumes and awns.

Journal Article↗
PubMed1991

The place of fetal liver transplantation in the treatment of inborn errors of metabolism.

Over the last 16 years, 202 fetal tissue transplants have been performed in our department to treat 29 patients with severe inborn errors of metabolism without immunodeficiency, 26 patients with congenital and severe immunodeficiency diseases, and 2 patients with severe aplastic anaemia. The actuarial survival curve of patients with inborn errors of metabolism treated with fetal liver transplantation shows a 12-year survival of 77%. The condition of many of these patients has been improved by the treatment, but transplantation has had to be repeated in order to maintain clinical amelioration. Enzyme levels were not significantly and durably increased in peripheral blood but the quantities of substrates detected in sera and urines were significantly reduced and tissue deposits were stabilized.

Adolescent↗
PubMed1989

HLA class II antigens: structure, function, and expression in immunodeficiencies, autoimmune diseases, and allograft rejection.

The major histocompatibility complex (MHC) genes, coding for the histocompatibility leukocyte antigens (HLAs) are located on the short arm of chromosome 6. The HLA gene products are involved in many immune responses. Class I and class II molecules are composed of two subunits. Class I antigens are expressed on all cell types except red blood cells; class II molecules have a more limited distribution and are found only on certain cell types. A review of our current knowledge of the genes coding for these molecules, their biochemical analysis, and the current investigation into the three-dimensional structure of the glycoproteins will allow us to understand better how this complex system, which has been preserved in animal species throughout the evolutionary process, operates. The biologic significance of HLA class I and class II molecules in the development of an efficient immune system that permits our survival in the sea of microorganisms in which we are immersed is illustrated by the severe and lethal infections that occur when these antigens are absent. Important and interesting variations in class II antigen expression are also observed in certain autoimmune diseases. Furthermore, the role of these antigens in the allogeneic reaction of graft rejection has now been clearly identified. It has become increasingly apparent how important it is to understand the antigenic variation between organs, or even between cells within an organ, and to be able to identify the circumstances that are associated with modulation of antigen expression.

Autoimmune Diseases↗
PubMed1987

Survey of experimental data on fetal liver transplantation.

Fetal liver transplantation has been shown to induce hematological and immunological reconstitution in irradiated rodents, dogs, horses, and sheep. Engraftment and reconstitution without GvHD has been readily obtained using histocompatible donors. When mismatched fetal donors were used, a comparatively larger number of donor cells was required, in addition to pre-treatment of host with higher doses of irradiation or irradiation plus chemotherapy. Stem cell suspensions devoid of any T lymphocyte can be transplanted across major histocompatibility barrier without inducing overt GvHD. The transplanted animals become tolerant to both donor and host grafts.

Animals↗
PubMed1987

Ontogeny of T lymphocyte differentiation in the human fetus: acquisition of phenotype and functions.

Phenotype and functions of cells of the T lymphocyte lineage from fetal liver, thymus, spleen and bone marrow were investigated at various ages. T lymphocyte differentiation was shown to be initiated in the thymus after the 7th week of gestation. In this organ, a large number of cells with a phenotype comparable to that of children thymocytes and with a high proliferative response to phytomitogens was observed at the 14th week. The fetal liver and bone marrow never contained many T-cells and the liver was shown to be virtually devoid of any of these cells before the 13th week. Fetal spleen contained appreciable amounts of T-cells after the 13th week. Helper and suppressor activities of fetal thymocytes and splenocytes were acquired between the 12th and the 16th week, but they were never as complete nor as potent as those of adult lymphocytes. HLA antigens were detected in very low amount in lymphocytes from the various organs at the beginning of the second trimester and their expression was significantly enhanced by in vitro incubation with alpha-interferon (alpha-IFN), a procedure that permits easier HLA typing of fetal cells.

Antibodies, Monoclonal↗
PubMed1987

Fetal tissue transplantation, bone marrow transplantation and prospective gene therapy in severe immunodeficiencies and enzyme deficiencies.

The successful development of fetal tissue transplantation has resulted in therapeutical solutions for patients with a variety of diseases. Fetal liver transplants as well as bone marrow transplants, can completely cure patients with severe combined immunodeficiency disease. These transplants can also be applied to treat other types of immunodeficiency, hemopathies, and inborn errors of metabolism, in association with immunosuppressive therapy. Despite complete HLA incompatibility between transplanted stem cells and host cells, functional activities of donor-derived T-lymphocytes are not restricted. In severe forms of Di George syndrome, immunological reconstitution can be obtained by fetal thymus transplantation. It is expected that, in the near future, pure stem cell transplants and gene transplants will develop and will provide remarkable solutions for the therapy of a large number of diseases.

Bone Marrow↗