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A Criado

Publications and source records attributed to A Criado.

At least 19 recordsLinked to original sources
PubMed2006

New data on epizootiology and genetics of piroplasms based on sequences of small ribosomal subunit and cytochrome b genes.

As a continuation of our studies on molecular epizootiology of piroplasmosis in Spain and other countries, we present in this contribution the finding of new hosts for some piroplasms, as well as information on their 18S rRNA gene sequences. Genetic data were complemented with sequences of apocytochrome b gene (whenever possible). The following conclusions were drawn from these molecular studies: Theileria annulata is capable of infecting dogs, since it was diagnosed in a symptomatic animal. According to cytochrome b sequences, isolates from cows and dog present slight differences. The same isolates showed, however, identical sequence in the 18S rRNA gene. This exemplifies well the usefulness of the mitochondrial gene for examining infra-specific variation. Babesia bovis is an occasional parasite of equines, since it was detected in two symptomatic horses. We found evidence of genetic polymorphism occurring in the 18S rRNA gene of Spanish T. equi-like and B. ovis isolates. B. bennetti from Spanish seagull is loosely related to B. ovis, and might represent a genetically distinct branch of babesids. A partial sequence of a cytochrome b pseudogene was obtained for the first time in Babesia canis rossi from South Africa. The pseudogene is distantly related to B. bigemina cytochrome b gene. These new findings confirm the ability of some piroplasms to infect multiple hosts, as well as the existence of a relatively wide genetic polymorphisms with respect to the cytochrome b gene. On the other hand, the existence of mtDNA-like pseudogenes of possible nuclear location in piroplasms is interesting due to their possible impact on molecular phylogeny studies.

Animals↗
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

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↗
PubMed2004

Direct automatic screening of soils for polycyclic aromatic hydrocarbons based on microwave-assisted extraction/fluorescence detection and on-line liquid chromatographic confirmation.

An integrated screening-confirmation system for PAHs in soils is presented. The sample screening configuration comprises on-line microwave-assisted extraction of the selected pollutants, followed by continuous preconcentration and sample clean-up on RP-C18. Those samples for which the total concentration is close to or above the threshold limit established (10 microg/g) are subjected to liquid chromatographic separation for confirmation. An evaluation of the qualitative data obtained was also carried out, by calculating the unreliability zone as well as the false positive and false negative rates. The whole method (extraction/determination/confirmation) was validated using industrial soil and harbour sediment certified reference materials (IRMM, European Commission CRM 524 and CRM 535). Application to the screening of solid environmental samples with subsequent confirmation of the results is also presented.

Chromatography, High Pressure Liquid↗
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

Chemical isomerism as a key to explore free-energy landscapes in disordered matter.

The effects of a minor chemical modification on the microscopic structure of a material in its glass and crystal phases are investigated by the concurrent use of neutron diffraction and computer simulation. Significant changes in short-, intermediate-, and long-range order are found, resulting from the change in molecular structure. These differences are explainable by a shift in the balance between directional and excluded-volume interactions.

Journal Article↗
PubMed2002

Rifampin and isoniazid resistance associated mutations in Mycobacterium tuberculosis clinical isolates in Seville, Spain.

The susceptibility phenotypes of 964 clinical isolates of Mycobacterium tuberculosis were studied over a 7-year period in Seville, Spain. Thirty-eight (3.9%) strains were rifampin (RMP) resistant, 79 (8.2%) were isoniazid (INH) resistant and 22 (2.3%) were resistant to at least both antimicrobials (multidrug-resistant, MDR). We studied the mechanisms of resistance to these drugs in 94 resistant clinical isolates of M. tuberculosis using three molecular methods: 1) PCR-single strand conformation polymorphism (SSCP) analysis, 2) RFLP analysis using B1/B2 primers, and 3) sequence analysis. Five different mutations were detected in the rpoB gene: Ser531-->Leu (72.3%), His526-->Asp (12.8%), Asn518-->Ser (2.1%), Gln513-->Leu (2.1%) and a nine-nucleotide deletion (2.1%). In the case of resistance to INH, four different mutations in the katG gene were detected, Ser315-->Thr (58.0%), Ser315-->Leu (2.9%), partial deletion (5.8%) and Ile304-->Val (1.4%), while in the inhA regulatory region the only mutation was the nucleotide substitution C209T (4.3%). No mutation was found in the ahpC promoter.

DNA, Bacterial↗
PubMed2001

[Prolonged muscle weakness associated with the administration of non-depolarizing neuromuscular blocking agents in critically ill patients].

Generalized muscle weakness is a common disorder in patients undergoing mechanical ventilation. The cause is unknown but is attributed to the administration of non-depolarizing neuromuscular blocking and other drugs, mainly steroids, or to the presence of sepsis or multiorgan failure. Specific clinical pictures (polyneuropathy, myopathy and prolonged muscle weakness) develop in function of the underlying cause, although etiological factors may sometimes interact. Differential diagnosis is carried out with the aid of electromyography and pathology of the peripheral muscle. Costs are high and prognosis is uncertain. Completeness of neuromuscular blockade must be monitored in these patients to guide the administration of drugs, to avoid overdoses, to maintain muscle activity and to detect a chain of reactions among concomitant medications or pathophysiologic changes.

Critical Illness↗
PubMed2001

[Anesthesia in a case of Holt-Oram syndrome].

A 19-year-old man with Holt-Oram syndrome (HOS) underwent emergency surgical treatment of an occipital abscess. He presented total aplasia of the radius and first and second finger of the left hand, asymmetric thorax and complex cyanotic cardiopathy with double output of the right ventricle that had been treated on several occasions, malpositioning of the large vessels and interventricular conduction. He had been treated with digoxin for episodes of supraventricular tachycardia. After premedication with 0.4 mg of atropine, balanced general anesthesia was induced with etomidate and remifentanil and maintained with O2/air/desflurane and infused remifentanil. The patient remained hemodynamically stable during surgery and tubes were removed in the operating room with no complications. HOS, a hereditary disease characterized by congenital malformations of the upper extremities and the heart, is often associated with rhythm disorders. Problems that may develop in such patients during anesthesia include difficulty catheterizing vessels, difficult orotracheal intubation and ventilation, hemodynamic instability, and the presentation of arrhythmias and cardiac arrest.

Adult↗
PubMed2000

Fast urinary screening for paracetamol using on-line microwave assisted hydrolysis and spectrophotometric detection.

A fully automated urinary screening system for paracetamol and its metabolites is proposed. The method comprises on-line acid microwave assisted hydrolysis of the drug to p-aminophenol followed by reaction with o-cresol in alkaline medium. The indophenol blue dye formed can be continuously monitored at 620 nm. The detection limit achieved, 0.1 microgram ml-1, allows a high dilution of the samples, thus reducing potential interferences from the sample matrix (mainly protein degradation during urine hydrolysis). The proposed screening system also possesses an adequate selectivity, as the major interferent, epinephrine, is tolerated at concentrations higher than those that could be found in the positive urine samples. The reproducibility, expressed as relative standard deviation, was 3.0% and the sample frequency 20 h-1. The reliability of the method was established at five concentrations (between 0.5 and 4 times the detection limit). Finally, it was applied to the screening of several human urine samples. The results obtained were compared with those provided by batch acid hydrolysis, and were similar in all instances.

Acetaminophen↗
PubMed2000

Use of real-time PCR and fluorimetry for rapid detection of rifampin and isoniazid resistance-associated mutations in Mycobacterium tuberculosis.

Very fast amplification of DNA in small volumes can be continuously monitored with a rapid cycler that incorporates fluorimetric detection. Primers were designed to amplify a 157-bp fragment of the rpoB gene spanning codons 526 and 531 and a 209-bp fragment of the katG gene spanning codon 315 of Mycobacterium tuberculosis. Most mutations associated with resistance to rifampin (RMP) and isoniazid (INH) in clinical isolates occur in these codons. Two pairs of hybridization probes were synthesized; one in each pair was 3' labeled with fluorescein and hybridized upstream of the codon with the mutation; the other two probes were 5' labeled with LightCycler-Red 640. Each pair of probes recognized adjacent sequences in the amplicon. After DNA amplification was finished by using a LightCycler, the temperature at which the Red 640 probe melted from the product was determined in a 3-min melt program. Twenty M. tuberculosis clinical isolates susceptible to streptomycin, INH, RMP, and ethambutol and 36 antibiotic-resistant clinical M. tuberculosis isolates (16 resistant to RMP, 16 to INH, and 4 to both antimicrobial agents) were amplified, and the presence of mutations was determined using single-strand conformation polymorphism analysis, the LiQor automated sequencer, and the LightCycler system. Concordant results were obtained in all cases. Within 30 min, the LightCycler method correctly genotyped all the strains without the need of any post-PCR sample manipulation. Overall, this pilot study demonstrated that real-time PCR coupled to fluorescence detection is the fastest available method for the detection of RMP and INH resistance-associated mutations in M. tuberculosis clinical isolates.

Antitubercular Agents↗
PubMed1998

Warm ischemic time tolerance after ventilated non-heart-beating lung donation in piglets.

OBJECTIVE: The availability of lungs for transplantation could be ameliorated with the use of organs retrieved from ventilated non-heart-beating donors (VNHBD). The aim of this work is to determine the limit to tolerable in situ warm ischemia time (WIT) for lung grafts after circulation is stopped. METHODS: Twenty piglets underwent left lung allotransplantation. Animals were randomly allocated based on the donor's status before lung harvesting into the following study groups: Sham (n = 5), Heart-beating donors-non-warm ischemia; I-30 (n = 5), I-60 (n = 5) and I-90 (n = 5), VNHBD-WIT of 30, 60 and 90 min, respectively. Right pulmonary artery and bronchus were permanently occluded one hour after transplantation. Assessment of pulmonary function was monitored hourly by hemodynamic, oxygenation and pulmonary mechanic measurements during a period of 6 h after reperfusion. Lung grafts were weighed pre- and post-transplantation. RESULTS: Cold ischemic time was similar for all groups, and averaged 80.1+/-2.7 min. Final mean lung weight was significantly greater in VNHBD (92.5+/-3.1 g vs. Sham values 75.6+/-2.4 g, P < 0.01). After right lung exclusion, hemodynamic changes consisted of a sustained increase in pulmonary vascular resistance and a reduction in cardiac output. Lung mechanics also modified, with a rise in airway resistance and a fall in compliance. CONCLUSIONS: Post-transplantation lung graft function from VNHBD with up to 90 min of WIT, is equivalent to those achieved by grafts harvested after heart-beating donation. This method may be a promising strategy of increasing the pulmonary donor pool.

Animals↗
PubMed1996

[Predictive factors of inotropic support in myocardial revascularization surgery].

OBJECTIVES: The use of perioperative inotropics in myocardial revascularization surgery can be considered a marker of ventricular dysfunction, the etiology of which involves a variety of pre- and intraoperative factors. Knowledge of the risk factors and their relative importance can allow them to be modified for improved outcome. This study aims to determine the incidence of and factors that predict the need for inotropic support in order to finalize extracorporeal circulation and in the first 6 hours after myocardial revascularization. PATIENTS AND METHODS: Two hundred forty-two patients who underwent myocardial revascularization were studied retrospectively. The parameters collected were age, sex, NYHA classification, left ventricular telediastolic pressure at baseline and after contrast, ejection fraction, collateral circulation, number of distal anastomoses, time of clamping, time of extracorporeal circulation, need for inotropic support to end extracorporeal circulation and during the first 6 hours after surgery. RESULTS: Inotropics were used in 27.6% of the sample. The need for inotropic support was related to female sex (odds ratio [OR] 3.85 with 95% confidence interval [CI], 1.56-9.49); NYHA class III (OR 2.13 with 95% CI, 1.05-4.32) or IV (OR 10.16 with 95% CI, 3.22-32.13); low injection fraction (OR 2.41 with 95% CI, 1.22-4.76); and prolonged extracorporeal circulation (OR 2.97 with 95% CI, 1.54-5.76). CONCLUSIONS: The independent variables associated with the need for inotropic support during the perioperative period in myocardial revascularization are NYHA functional class III and IV, female sex, low injection fraction and prolonged extracorporeal circulation. New techniques for myocardial protection during extracorporeal circulation, plus adequate peroperative stabilization of patients and shorter time of extracorporeal circulation will probably diminish short term morbidity in revascularization surgery.

Aged↗