PubMed Health⌕ Search

Biomedical subjects

J Sanchez

Publications and source records attributed to J Sanchez.

At least 19 recordsLinked to original sources
PubMed1995

[Metrology of airborne particles carrying the principal air allergens].

The relationship between exposure to aeroallergens and the acquisition of allergy and asthma has been shown over the past ten years. Thanks to new developments for detecting major allergens amongst the principle aeroallergens, in future it will be possible to measure their airborne concentration and to determine the particle size of particles carrying them. We report the results obtained from three studies in which we have shown that airborne mites Group I and II and cockroaches Bla g 1 and Bla g 2 allergens have a broadly similar airborne behaviour. That is to say that they are not measurable unless the atmosphere is artificially disturbed and they are carried principally on particles of > 10 microns. On the other hand, 30-40% of cat allergens are carried on particles < 5 microns and measurable in the air without any artificial disturbance. According to our data and those of the literature, we propose a different classification for aeroallergens according to characteristic aerodynamics. Although some progress in the standardisation of techniques for sampling airborne allergens may have been accomplished, other studies are required to improve their reliability in order that airborne measurements can become a marker of allergic exposure in both domestic and occupational environment.

Air↗
PubMed1992

A Streptomyces glaucescens endodeoxyribonuclease which shows a strong preference for CC dinucleotide.

We have characterized a deoxyribonuclease from Streptomyces glaucescens that cleaves double-stranded DNA preferably between the dinucleotide 5'-CC-3'. The cleavage specificity was demonstrated by both analysis of the terminal nucleotides of the generated fragments and DNA sequencing of partially digested DNA. Digestion of lambda DNA with this enzyme resulted in the production of double-stranded fragments with 5' and/or 3'-protruding single-stranded tails. DNase I footprinting experiments indicated that the nuclease specifically binds to its cleavage sites on the DNA under non-catalytic conditions. The enzyme is not affected by cytosine methylation in hemimethylated DNA.

Bacteriophage lambda↗
PubMed1992

Suppression of gene amplification in human cell hybrids.

Gene amplification, one example of genetic instability, is of prognostic and clinical importance in neoplasia. In tumorigenic cells, gene amplification occurs at a very high frequency, whereas in normal diploid fibroblasts the event is undetectable by the clonogenic assay. To investigate genetic control of gene amplification, amplification frequency was measured in hybrids of tumorigenic cells and normal diploid cells. The ability to amplify an endogenous gene behaved as a recessive genetic trait, and control of gene amplification potential segregated independently of tumorigenicity and immortality.

Aspartate Carbamoyltransferase↗
PubMed1992

A pediatric trauma center without a pediatric surgeon: a four-year outcome analysis.

Approximately 25% of all injury victims are in the pediatric age group, and one in four injured children will require a pediatric trauma center. According to the American College of Surgeons as well as many state guidelines, a level I pediatric trauma team should be directed by a pediatric surgeon. In 1986, the pediatric surgeon left our pediatric trauma center, but the center remained open under a cooperative effort by the adult trauma surgeons and pediatric intensivists. We have retrospectively reviewed the charts of all pediatric trauma patients (age less than or equal to 15 years) for the subsequent 4 years to determine the outcome of treatment without a pediatric surgeon. During this period, we treated 303 pediatric patients with multiple or serious single-system injuries. The mean age was 6.9 +/- 0.3 (SEM) years and 66% were boys. Falls were the cause of injury in 31% of the patients, with pedestrian/bicycle, motor vehicle crashes, and penetrating injuries resulting in 26%, 19%, and 3% of the injuries, respectively. The mean ISS was 15.6 +/- 0.8, and 73% of the patients had at least one AIS greater than or equal to 3. Surgical procedures were required in 48% of the patients. There were 27 deaths in this group, most commonly related to head injury (89%). The mean Pediatric Trauma Score of the patients who died was 1.6 +/- 0.8 and no patient with a Pediatric Trauma Score greater than 7 died.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1992

Detection of Mycobacterium paratuberculosis antigen with colloidal immunogold in naturally infected sheep.

The anti-Mycobacterium paratuberculosis polyclonal serum is proved useful for labelling Mycobacterium paratuberculosis in glutaraldehyde-osmium-fixed and epon-embedded intestinal samples from sheep with clinical symptoms of paratuberculosis. M. paratuberculosis marked with antibody-coated colloidal gold stain was seen in macrophages, epithelioid cells, giant cells and neutrophils throughout intestinal mucosa. In large macrophages with a low lysosomal content, a great number of intact mycobacteria was seen within phagosomes. In macrophages with average lysosomal content, very few intact mycobacteria or mycobacterial debris were present and lysosome-phagosome fusions were observed. Mycobacteria within neutrophils were scanty. These results show the usefulness of colloidal immunogold techniques for studies of the pathogenesis of paratuberculosis.

Animals↗
PubMed1992

Diffuse thallium-201-chloride uptake in hypermetabolic bone marrow following treatment with granulocyte stimulating factor.

Diffuse abnormal uptake of 201Tl-chloride in the bone marrow is described in an AIDS patient with Kaposi's sarcoma who received chemotherapy. The patient developed severe leukopenia that was treated by granulocyte stimulating factor (GCSF). The white blood cells increased from 1500 to 6200 over a period of 4 days. After chemotherapy, the tumor was negative for thallium uptake.

Acquired Immunodeficiency Syndrome↗
PubMed1992

Erythrocyte metabolism in exercise. A comparative study in anaemized rats.

The influence of young red cells induced by anaemization on physical performance had been studied in rats. The anemic rats with immature red cells, higher levels of ATP, glutamate-oxalacetate transaminase (GOT) and lactate dehydrogenase (LDH) showed an elevated lactate and ammonia concentration at the first week of training. The blood analysis also showed that the rise in 2,3-DPG concentration can be related with the increase of glycolytic activity during exercise in both groups, anemic and non anemics rats.

2,3-Diphosphoglycerate↗
PubMed1992

The effects of platelet-activating factor (PAF) and a PAF antagonist (CV-3988) on smoke inhalation injury in an ovine model.

The role of platelet-activating factor (PAF) in inhalation injury was studied in sheep, using CV-3988, a PAF antagonist. Following smoke exposure, 15 sheep were divided into three groups of five. Group I animals were untreated; group II animals were treated with CV-3988 before and after exposure; group III animals were treated only after exposure. In group I, platelet and WBC counts were markedly changed within 6 hours (p less than 0.05); in the treated groups, alteration of cell counts was not obvious. Blood malondialdehyde (MDA) levels were increased significantly only in group I. Blood PGE2 and TXB2 levels did not differ among the groups. Mean tissue MDA and mean bronchoalveolar lavage fluid (BALF) MDA concentrations were significantly increased in group I (p less than 0.01); mean BALF TXB2 levels were significantly decreased in group I (p less than 0.01). These data suggest that PAF affects inhalation injury through modulation of lipid oxygenation and that PAF antagonists may offer therapeutic benefit in the management of this injury.

Animals↗
PubMed1991

Autoregulation of the immune response in autoimmune disease and cardiac transplantation by photoinactivated autologous lymphocytes.

These studies demonstrate that photochemotherapy can be successfully evaluated in animal models. The therapy mediates specific suppression of immune responses and appears to operate at the level of the effector T cells. Future studies will focus on isolation and characterization of the host response to photochemotherapy. The extention of this form of therapy to conditions mediated by dysfunctional regulation of effector T cells is already in progress in clinical trials of cardiac allograft transplantation and autoimmune disease. The results of these trials will provide more evidence on the role of this form of therapy in autoregulation of the immune response.

Animals↗
PubMed1991

Synthesis in Vibrio cholerae and secretion of hepatitis B virus antigens fused to Escherichia coli heat-labile enterotoxin subunit B.

A simple and effective electroporation method for the transformation of Vibrio cholerae with nonmobilizable plasmids is described. Expression plasmids directing the synthesis of fusion proteins with the subunit B of Escherichia coli heat-labile enterotoxin B (LT-B) were transformed into nontoxinogenic V. cholerae vaccine strains. A protein consisting of two overlapping immunodominant antibody-binding sites of the hepatitis B virus (HBV) middle surface antigen fused to the C terminus of full-length LT-B was secreted into the supernatant of V. cholerae cultures, whereas two other LT-B/HBV fusion proteins were mostly retained within the cells or rapidly degraded in the culture supernatant. While the secretion of fusion proteins with cholera toxin subunit B (CT-B) from V. cholerae has been described, this is to our knowledge the first report describing extracellular secretion of defined foreign epitopes fused to LT-B in V. cholerae. The fusion of guest epitopes to LT-B or CT-B and secretion in V. cholerae could be an interesting system to rapidly produce pure fusion proteins for immunisation, functional studies or diagnostic procedures. An LT-B/pre-S2 fusion protein purified from the supernatant of recombinant V. cholerae induced serum IgG antibodies against LT-B and against the HBV middle surface antigen in mice after parenteral and oral immunisation.

Animals↗
PubMed1991

Orthopaedic treatment in tibial diaphyseal fractures. Risk factors affecting union.

A retrospective of 216 tibial fractures treated orthopedically was carried out. The aim was to analyze a set of clinicobiological parameters that owing to their assumed action on the physiological model of consolidation can be considered as risk factors to be taken into account in all kinds of orthopedic treatment, because they may lead to a lengthening of the normal consolidation time of the fracture. The variables analyzed were the following: type of immobilization, causative agent of the fracture, location of the focus of the fibular fracture, initial displacement, degree of conminution, type of wound, type of fracture, appearance of radiologically observable callus, commencement of weight-bearing, post-fracture hematoma, secondary displacement, and infection of soft tissues. In the particular case of immobilization by an ischiopedic plaster cast, the following parameters showed a greater degree of prognostic significance: initial displacement, secondary displacement, and age.

Adult↗