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P Caballero

Publications and source records attributed to P Caballero.

At least 19 recordsLinked to original sources
PubMed2005

[Usefulness of fast ELISA determination of D-dimer levels for diagnosing pulmonary embolism in an emergency room].

OBJECTIVE: To determine the sensitivity and negative predictive value of D-dimer levels measured by fast enzyme-linked immunoabsorbent assay (ELISA) in pulmonary embolism. PATIENTS AND METHODS: Prospective study of consecutive patients with suspicion of pulmonary embolism attended in the Emergency Room of the Hospital de La Princesa in Madrid, Spain. Thromboembolism was diagnosed with an algorithm established in the hospital, and D-dimer levels were determined by fast ELISA (VIDAS D-dimer Assay) in each patient suspected of pulmonary embolism. Patients with negative findings from a test not considered a reference method for thromboembolism were followed for 3 months. RESULTS: Of 132 patients with clinical suspicion, 28 (21.2%) were positive and 104 (78.7%) were negative for embolism. D-dimer levels were below 0.5 microg/mL in 31 patients, 30 of whom did not have pulmonary thromboembolism whereas 1 did. D-dimer levels were abowe 0..5 microg/mL in 101 patients; thromboembolism did not occur in 74 of these but was reported in the remaining 27. For a value of 1 microg/mL, 66 patients had values below the cut off, 3 of whom presented pulmonary embolism. The remaining 66 patients had D-dimer levels above or equal to 1 microg/mL; 25 of them had a positive diagnosis for embolism and 41 had a negative diagnosis. Sensitivity and negative predictive values were 96.4% (95% confidence interval [CI], 79.8%-99.9%) and 96.8% (95% CI, 81.5%-98.8%), respectively, at a cut off of 0.5 microg/mL; and 89.2% (95% CI, 70.6%-97.2%) and 95.45% (95% CI, 86.4%-98.8%), respectively, at a cut off of 1 microg/mL. CONCLUSIONS: In an emergency room, thromboembolism can be excluded if plasma levels of D-dimer measured by fast ELISA are below 0.5 microg/mL because of the high negative predictive value at this cut off.

Aged↗
PubMed2005

[Cystic fibrosis in adults: inter- and intraobserver agreement for the Brasfield and Chrispin-Norman chest radiography scoring systems and correlation with clinical data and spirometry].

OBJECTIVE: Most chest radiography scoring systems for patients with cystic fibrosis have been developed for children but are also used for adults. Our aim was to evaluate the intra- and interobserver variability of 2 radiographic scoring systems in adults with cystic fibrosis and to assess the correlation of these systems with clinical and spirometric parameters. PATIENTS AND METHODS: The chest x-rays of 24 adult patients with cystic fibrosis were compared using 2 scoring systems (Brasfield and Chrispin-Norman). The x-rays were scored by 2 radiologists and reevaluated 4 months later by 1 of the 2 observers. Intra- and interobserver agreement was assessed using the intraclass and Pearson's correlation coefficients. The radiographic scores were compared to lung function tests and other clinical data. RESULTS: Both intra- and interobserver agreement were high (r > or = 0.9 and the intraclass correlation coefficient > or = 0.85 with both systems for both samples). Both scoring systems correlated with spirometry results: forced expiratory volume in the first second (FEV1) (r = 0.64 and r = 0.55), FEV1% (r = 0.75 and r = 0.72), and the percentage of forced vital capacity in relation to the predicted value (r = 0.63 and r = 0.056). We found no association between scoring system and sex, age, or body mass index. CONCLUSIONS: Assessment of chest radiographs of adult patients with cystic fibrosis by the Brasfield and Chrispin-Norman scoring systems shows good intra- and interobserver agreement. Both systems correlate well with lung function variables, especially FEV1.

Adult↗
PubMed2003

Impact of a nucleopolyhedrovirus bioinsecticide and selected synthetic insecticides on the abundance of insect natural enemies on maize in southern Mexico.

The impact of commonly used organophosphate (chlorpyrifos, methamidophos), carbamate (carbaryl), and pyrethroid (cypermethrin) insecticides on insect natural enemies was compared with that of a nucleopolyhedrovirus (Baculoviridae) of Spodoptera frugiperda (J. E. Smith) (Lepidoptera Noctuidae) in maize grown in southern Mexico. Analyses of the SELECTV and Koppert Side Effects (IOBC) databases on the impact of synthetic insecticides on arthropod natural enemies were used to predict approximately 75-90% natural enemy mortality after application, whereas the bioinsecticide was predicted to have no effect. Three field trails were performed in mid- and late-whorl stage maize planted during the growing season in Chiapas State, Mexico. Synthetic insecticides were applied at product label recommended rates using a manual knapsack sprayer fitted with a cone nozzle. The biological pesticide was applied at a rate of 3 x 10(12) occlusion bodies (OBs)/ha using identical equipment. Pesticide impacts on arthropods on maize plants were quantified at intervals between 1 and 22 d postapplication. The biological insecticide based on S. frugiperda nucleopolyhedrovirus had no adverse effect on insect natural enemies or other nontarget insect populations. Applications of the carbamate, pyrethroid, and organophosphate insecticides all resulted in reduced abundance of insect natural enemies, but for a relatively short period (8-15 d). Pesticide applications made to late-whorl stage maize resulted in lesser reductions in natural enemy populations than applications made at the mid-whorl stage, probably because of a greater abundance of physical refuges and reduced spray penetration of late-whorl maize.

Animals↗
PubMed2002

[Hookwire localization of pulmonary nodules for video-thorascopic surgical resection].

OBJECTIVES: To assess the usefulness of a technique for inserting hookwires guided by computed tomography to locate and resect pulmonary nodules by video-assisted thoracoscopy. To describe the procedure and its complications. PATIENTS AND METHODS: Nine pulmonary nodules were located in nine patients. All were </= 2 cm in diameter, radiologically undefined and of unknown origin. Four patients had a history of cancer. The nodules were located using the needle/hookwire system (Kopans), guided by computed tomography and were resected by video-assisted thoracic surgery. RESULTS: The hookwire was placed correctly in 8 patients and incorrectly in 1. Thoracotomy was necessary for 1 patient. The histologic diagnosis was benign for all 9 nodules; 5 were hamartomas, 2 were necrotic or fibrotic nodules, 1 was a granuloma and 1 was an anthracotic node. Hospital stay ranged from 1 to 8 days (mean 3.3 days). CONCLUSION: The location of pulmonary nodes by hookwire and needle for later resection by video-assisted thoracoscopic surgery is a simple, safe way to facilitate removal in some cases, for diagnosis and treatment.

Adult↗
PubMed2002

Contents of cry genes and insecticidal toxicity of Bacillus thuringiensis strains from terrestrial and aquatic habitats.

AIMS: Two Bacillus thuringiensis collections from terrestrial and aquatic habitats were compared in order to study the possible interrelationships between habitat and biological characteristics (serovar, cry genes content and toxicity). METHODS AND RESULTS: Bacillus thuringiensis strains were characterized by serology, PCR, and one-dose treatment against the noctuids Helicoverpa armigera and Spodoptera exigua, and the dipteran Tipula oleracea. A total of 12 and 10 different serovars were identified within terrestrial and aquatic strains, respectively. The number of non-toxic strains was greater in aquatic (41.6%) than in terrestrial habitats (5.3%). The genes cry1C, cry1D and cry1E were significantly more frequent in the terrestrial habitat. The cry1B gene was very frequent within thuringiensis strains. CONCLUSIONS: A high diversity was found in terms of serovars present and cry genes content in both collections. The relative frequency of individual cry genes was different in both collections, and a serovar-dependent distribution of the cry1B gene was found. Some strains sharing the same set of cry genes differed in their toxicity, suggesting important differences in gene expression. SIGNIFICANCE AND IMPACT OF THE STUDY: The inter-relationships between serology, cry gene content and toxicity may allow a better understanding of B. thuringiensis ecology.

Animals↗
PubMed2000

Isolation and characterization of Bacillus thuringiensis strains from aquatic environments in Spain.

Samples collected from aquatic environments from Spain were analyzed for the occurrence and dipteran toxicity of Bacillus thuringiensis. From a total of 41 samples, 122 isolates were obtained, yielding a B. thuringiensis index of 0.22. Isolates were assigned to 13 different serovars, with serovar thuringiensis (serotype H1) the most frequently found. Toxicity tests carried out revealed that eight isolates (6.6% out of the total) were active against Tipula oleracea larvae. Serological tests assigned these toxic isolates to serovar thuringiensis. The toxicity found in these isolates against the tipulid was approximately seven times lower than that shown by the standard strain B. thuringiensis ser. israelensis IPS-82. Implication of Cry2A protein in toxic activity is hypothesized.

Animals↗
PubMed2000

Characterization of Bacillus thuringiensis ser. balearica (Serotype H48) and ser. navarrensis (serotype H50): two novel serovars isolated in Spain.

The novel strains of Bacillus thuringiensis PM9 and NA69, isolated from soil samples in Spain, were classified and characterized in terms of their crystal proteins, plasmid profile, cry genes content, and their toxicological properties against several species of Lepidoptera, Coleoptera, and Diptera. Both strains share morphological and biochemical characteristics with previously described B. thuringiensis strains, although their unique H antigens identify them as two new serotypes. Two new serovar names, B. thuringiensis serovar balearica (H serotype 48) and B. thuringiensis serovar navarrensis (H serotype 50) are proposed for the type strains PM9 and NA69, respectively.

Animals↗
PubMed2000

Molecular and insecticidal characterization of a Bacillus thuringiensis strain isolated during a natural epizootic.

A new Bacillus thuringiensis strain belonging to the serovar aizawai was isolated from a dead larva of the lepidopteran Mythimna loreyi collected in a corn crop in Spain during a natural epizootic. This strain, which was named Leapi01, was compared with the kurstaki and aizawai strains isolated from Dipel(R) and Xentari(R), by electron microscopy, SDS-PAGE, plasmid pattern, PCR and insecticidal activity. This strain showed similar morphological and biochemical characteristics to the standard strains. The content in cry genes of Leapi01 was analysed with a set of general and specific primers recognizing most of the cry genes reported to date. DNA amplification was obtained with primers corresponding to six genes and, to clearly determine the identity of the genes, the amplified fragments were sequenced and corresponded to cry1Aa, cry1Ab, cry1Ca, cry1Da, cry2Ab and cry1Ia. However, the proteins encoded by two of these genes, Cry2 and Cry1I, were not detected in the SDS-PAGE of the purified parasporal bodies. The insecticidal activity of Leapi01 was determined by bioassays against two Lepidoptera species, Helicoverpa armigera and Spodoptera littoralis, that were found to be very susceptible to Leapi01 purified crystals. Since two of the cry genes identified in Leapi01 appear to be silent, other factors may be involved in the toxicity of the strain. As a result of this study, the potential of Leapi01 as biological control agent is discussed, with special emphasis on the high toxicity and relatively broad spectrum activity compared with two B. thuringiensis strains that are the active ingredients of commercial preparations commonly used as bioinsecticides.

Animals↗
PubMed2000

Increasing the daily dose of recombinant follicle stimulating hormone (Puregon) does not compensate for the age-related decline in retrievable oocytes after ovarian stimulation.

A prospective, randomized, double-blind, multicentre (n = 6) study was conducted to compare the influence of either a 150 or 250 IU daily fixed-dose regimen of recombinant follicle stimulating hormone (FSH, Puregon) on the number of oocytes retrieved and the total dose used in down-regulated women between 30 and 39 years of age undergoing ovarian stimulation. In all, 138 women were treated with recombinant FSH, 67 with 150 IU and 71 with 250 IU. The number of oocytes retrieved in the low-dose group was 9.1 compared to 10.6 in the high-dose group (not significant). In the 30-33 years of age class receiving the 250 IU dose, a surplus of 4.2 oocytes (14.8 versus 10.6) was found, whereas in the 37-39 age class nearly one oocyte more was retrieved in the 150 IU group (8.1 versus 7.4). The total dose used to reach the criterion for human chorionic gonadotrophin (HCG) administration was 1727 IU for the women treated with 150 IU daily and 2701 IU for the 250 IU treated women (P < 0. 001). No significant relationships were found between serum FSH concentrations as obtained in the early follicular phase and the number of oocytes collected, or the total dose. It is concluded that in women between 30 and 39 years of age, the decline in number of oocytes retrieved with increasing age cannot be overcome by augmenting the daily dose of recombinant FSH from 150 to 250 IU.

Adult↗
PubMed2000

[Bullous emphysema and neurofibromatosis].

Clinical and image findings in a 43 year-old smoker man with advanced lung bullous emphysema and von Recklinhausen's neurofibromatosis are presented. Bullous emphysema and subpleural neurofibromas were detected in a chest computed tomographic study. The possible association or independence of these two conditions is discussed.

Adult↗
PubMed1999

Four genotypic variants of a Spodoptera exigua Nucleopolyhedrovirus (Se-SP2) are distinguishable by a hypervariable genomic region.

Four genotypes named SP2A, SP2B, SP2C and SP2D were obtained in vivo by infecting S. exigua larvae with limiting dilutions of the Spanish field isolate Spodoptera exigua Nucleopolyhedrovirus (Se-SP2) of SeMNPV. The cloning of variants SP2A, SP2B and SP2C took 1, 6, and 3 passages, respectively, before the DNA profiles showed all bands in equimolar concentrations, and they remained constant for at least six further passages indicating the stability of their genotypes. The SP2D variant isolation took over ten passages and it was genetically less stable. Physical maps of their genomes were constructed for the restriction enzymes BamHI, BglII, PstI, and XbaI. The region between 8-10 m.u. was highly variable and characteristic of each cloned genotype and, hence, can be used as RFLP markers for all four genotypic variants. This region, included in the PstI-MB fragment, was cloned and sequenced showing that all the Se-SP2 variants contained a homologous region (hr) with a variable number of 98 bp sequences tandemly repeated, which were used to distinguish genotypic variants from each other. The biological activity of the genotypic variants SP2A, SP2B, and SP2C when compared in terms of LD50 and LT50, were not significantly different. However, the SP2D genotypic variant was found to be significantly less infective (higher LD50). The emergence of new genotypes in the Se-SP2 field populations is discussed.

Animals↗
PubMed1999

Characterization of Bacillus thuringiensis serovar bolivia (serotype H63), a novel serovar isolated from the Bolivian high valleys.

The type strain Bacillus thuringiensis var. bolivia (serotype H63), isolated from the Bolivian high valleys, has been characterized at different levels. Its parasporal crystal has an unusual shape and it is composed of a protein of 155 kDa which shows two bands of 75 and 80 kDa after activation. Analysis by PCR shows the presence of cry1 genes, and amplification with specific primers gave products for cry1 E, cry1 D, cry4 A and cry4 B with sizes different to those expected. Immunoblotting tests showed positive reaction for Cry1 E, Cry3 A, Cry4 A and Cry11 A crystal proteins. The plasmid pattern revealed two large and two small plasmids. Toxicity tests were performed against 14 insects and a slight toxicity was found against Plutella xylotella and Trichoplusia ni.

Animals↗
PubMed1999

Identification and characterization of the new bacillus thuringiensis serovars pirenaica (serotype H57) and iberica (serotype H59)

Two new Bacillus thuringiensis strains have been classified by the H antigen of the cells and differentiated by their morphological, biochemical and molecular characteristics. The flagellar agglutination showed that both strains bore specific H antigens which allowed their classification as the new serotypes H57 and H59. The serovar names proposed for the type strains characterized in this work are B. thuringiensis ser. pirenaica, for the H serotype 57, and B. thuringiensis ser. iberica, for the H serotype 59. Further characterization of these strains, by means of SDS-PAGE, Western inmunodetection, plasmid profile and cry-gene identification by polymerase chain reaction, confirmed the originality of the two novel serotypes. Toxicity tests carried out against several insect species, belonging to the orders Lepidoptera, Diptera and Coleoptera, showed no detectable insecticidal activity for either of the B. thuringiensis strains.

Journal Article↗
PubMed1999

Selection of a nucleopolyhedrovirus for control of Spodoptera frugiperda (Lepidoptera: Noctuidae): structural, genetic, and biological comparison of four isolates from the Americas.

Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae) is the principal pest of maize in tropical and subtropical regions of the Americas. Larvae of this species are susceptible to a nucleopolyhedrovirus (NPV) which has attracted interest as a potential biocontrol agent. Four strains of NPV isolated from infected S. frugiperda larvae in the United States, Nicaragua, and Argentina were subjected to a structural, genetic, and biological comparison to select a candidate isolate for use in biocontrol experiments in Mexico and Honduras. All isolates had an occlusion body polyhedrin protein of 32 kDa, but the virions of each isolate differed subtly in the pattern and abundance of certain structural polypeptides revealed by SDS-PAGE analysis. Restriction endonuclease analysis of viral DNA confirmed that these isolates were strains of a single virus species but showed that they were not genetically homogeneous; each isolate could be differentiated from the others using common restriction enzymes. Droplet feeding bioassays indicated that an isolate from Nicaragua (Sf-NIC) and an isolate from the United States (Sf-US) had the highest infectivity when tested against 2nd instars originating from a Honduran S. frugiperda colony. No significant differences were detected in the speed of kill of Sf-NIC (102.7 h), Sf-US (102.3 h) and Sf-AR (103.4 h), whereas that of Sf-2 (97.3 h) was significantly shorter. Additional bioassays of the Sf-NIC isolate against 2nd to 6th instars demonstrated that LC50 values increased with larval stage from 2.03 x 10(5) OBs/ml for 2nd instars to 1.84 x 10(8) OBs/ml for 5th instars. The concentration required to elicit a lethal infection of 6th instars was so high that a reliable estimate of LC50 could not be obtained. The mean time to death for each stage challenged with the Sf-NIC isolate increased with instar from an average of 102.7 h in 2nd instars to 136.9 h in 5th instars.

Analysis of Variance↗
PubMed1998

Cloning and characterization of the phenylalanyl-tRNA synthetase beta subunit gene from Candida albicans.

A Candida albicans expression library was constructed from RNA isolated from regenerating protoplasts. A 1.4-kb cDNA clone was used to isolate a genomic fragment. Sequence analysis revealed an open reading frame of 593 amino acids with an overall identity of 63.6% with the phenylalanyl-tRNA synthetase beta subunit (FRS1) of Saccharomyces cerevisiae. We named it CaFRS1. It is located in a single copy in chromosome R, SfiI fragment M. Its expression showed a decrease during the cell wall regeneration process in protoplasts of both yeast and mycelial cells of C. albicans, suggesting its requirement thereof in initial steps of the cell wall synthesis.

Amino Acid Sequence↗
PubMed1998

Environmental distribution and diversity of Bacillus thuringiensis in Spain.

Bacillus thuringiensis was isolated from 301 out of 1,005 samples collected in Spain from agricultural and non-cultivated soils, dust from stored products, and dead insects. Based on the production of parasporal crystals, 1,401 isolates were identified as B. thuringiensis after examining 11,982 B. thuringiensis-like colonies. We found a greater presence of B. thuringiensis in dust from grain storages than in other habitats. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of the spore-crystal mixtures revealed diverse populations of B. thuringiensis which were differentiated in at least 92 distinct protein profiles. Serological identification also showed great diversity among the Spanish isolates which were distributed among 38 of the 58 known serovars. The most frequently found serovars were aizawai, kurstaki, konkukian, morrisoni, and thuringiensis, which together represented more than 50% of the serotyped isolates. In preliminary toxicity assays, a number of isolates were found to show significant insecticidal activity against the lepidopterans Heliothis armigera (76.1% of the assayed isolates), Spodoptera exigua (50.5%), and Plutella xylostella (19.7%). Thirty five isolates were toxic to both H. armigera and S. exigua, and eight were toxic to S. exigua and P. xylostella. Four and one isolates were toxic to the coleopterans Leptinotarsa decemlineata and Colaspidema atrum, respectively, and three to the dipteran Tipula oleracea. The electrophoretic pattern and serovar of most of the isolates with toxic activity were consistent with those reported in the literature, although other isolates revealed unusual protein profiles, were assigned to new H serovars, or were included in H serovars not previously reported within such pathotypes.

Animals↗