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P Morales

Publications and source records attributed to P Morales.

At least 73 records · Page 4Linked to original sources
PubMed1999

Antifungal prophylaxis during the early postoperative period of lung transplantation. Valencia Lung Transplant Group.

INTRODUCTION: Fungal infections occur frequently in lung transplant patients, with the highest risk being in the early postoperative period (the initial hospitalization after lung transplantation). Aspergillus is responsible for more than half of all fungal infections, and Aspergillus has even been considered a contraindication for lung transplantation because of its difficult therapy and frequently fatal outcome. The aim of this article is to evaluate the success of an antifungal prophylaxis protocol to prevent fungal infection in the immediate postoperative period in lung transplant recipients. MATERIAL AND METHODS: From March 1994 to March 1997, we performed 52 lung transplants in 31 men and 21 women who received antifungal prophylaxis with fluconazole, 400 mg/d, and aerosolized amphotericin B, 0.6 mg/kg/d, during the postoperative period. RESULTS: The mean (+/- SD) postoperative period duration was 49 +/- 27.5 days. No fungal infections were observed during this period, and all patients provided negative cultures. We also found no toxicity related to antifungal drugs. The dose of cyclosporine was easily adjusted in every recipient according to blood levels so that effective immunosuppression was not compromised. DISCUSSION: In our study, the removal of the lungs and antifungal prophylaxis with fluconazole and aerosolized amphotericin B prevented fungal infection in the postoperative period in all 52 lung transplant recipients.

Adolescent↗
PubMed1999

[The first simultaneous double unilateral lung transplantation in Spain: clinical course and results. Transplantation Group].

Unilateral lung transplantation of two organs allows two patients to benefit from a single donor. We report the first and only such transplants--carried out simultaneously in the same surgical unit--to be performed in Spain to date. The diagnosis was idiopathic pulmonary fibrosis in both cases and the donor came from the same hospital. No complications developed during the subsequent hospital stay. Two years later, both patients are asymptomatic and carrying out normal activities with no limitations.

Female↗
PubMed1999

Suspected intestinal torsion in a blacktip reef shark (Carcharhinus melanopterus).

A blacktip reef shark (Carcharhinus melanopterus) with a history of recurrent eversion or prolapse of the valvular intestine, arrived at the Steinhart Aquarium in June 1996 and was placed in a mixed species shark display. The eversion soon reappeared, and the animal became thin and anorexic. The everted portion of the intestine was bitten by another shark and became infected. Treatment included force-feeding, manual reduction of the eversion, hydrocortisone suppositories held in place with purse-string sutures, and injections of enrofloxacin. All treatments ultimately failed, and the animal died in March 1997. Necropsy revealed that the intestine had separated into two segments at the distal portion of the pyloric stomach (duodenum); both ends were scarred and sealed off. It is suggested that a torsion (twisting along the long axis) of the intestine was responsible for the condition.

Animals↗
PubMed1999

[Lung transplantation in cystic fibrosis. The results of the Clínica Puerta de Hierro (Madrid) and the Hospital La Fe (Valencia)].

UNLABELLED: Retrospective analysis of cystic fibrosis patients who underwent pulmonary transplantation at Clínica Puerta de Hierro, Madrid, and at Hospital La Fe, Valencia. Since the beginning of the programme and until March 1998, a total of 63 patients with cystic fibrosis were studied. Among transplanted patients, 18 were males and 16 females, with a mean age of 18.9 years. All patients underwent sequential bilateral pulmonary transplantation. After transplantation, the most common complication was bacterial pneumonia which affected all patients. Six patients had dehiscence or stenosis of the bronchial suture. Other specific complications of this condition by frequency were intestinal obstruction and diabetes mellitus. Six patients developed obliterans bronchiolitis and one of them underwent a repeat transplantation. Three out of the 34 patients died, and the likelihood of survival after one and three years was 94%. Respiratory function tests and PaO2 peaked at sixth post-transplantation month. CONCLUSION: Pulmonary transplantation is a therapeutic option to be considered for the patient with cystic fibrosis and severe involvement of his/her pulmonary disease.

Adolescent↗
PubMed1999

Influence of prolactin on the differentiation of mouse B-lymphoid precursors.

Development and activation of immune cells are submitted to hormonal influences, as illustrated by the roles of corticosteroids in thymus, pregnancy-related estrogens in B-cell development, or prolactin (PRL) on T-cell generation and function. We have analyzed the putative role of PRL in B lymphopoiesis and differentiation. We chose as an experimental model the interleukin (IL)-3 dependent BaF-3 pro-B cell line, which was transfected with the rat long form of the PRL receptor (PRL-R) and transferred from IL-3- to PRL-enriched media. When stimulated with PRL, the PRL-R transfectants underwent some changes characteristic of B-cell differentiation: (a) IL-2R alpha chain became positively controlled by PRL; (b) antiapoptotic Bcl-2 protein was induced by PRL in a dose-dependent manner; and (c) transcription of the pre-B cell receptor encoding the lambda5 gene was strongly up-regulated. We attempted to evaluate the differentiation-promoting activity of PRL in more physiological conditions, and the presence of PRL-R in bone marrow B-cell precursors was revealed. Furthermore, PRL promoted significant expansions of defined B-lineage cell populations in short-term bone marrow cell cultures. These findings suggest that PRL, in collaboration with other cytokines and hormonal influences, modulates B-cell development.

Animals↗
PubMed1999

Methyl bromide decreases excitability without having immediate toxic effects in rat hippocampal CA1 neurons in vitro.

Methyl bromide, a disinfectant gas amply used worldwide, is neurotoxic in humans and other mammals. To study its short-term effects on neurons, it was applied in aqueous solution to hippocampal slices of young rats (1.4 and 0.7 mM; for 8 minutes). Extracellular field recordings and intracellular microelectrode recordings from CA1 pyramidal neurons showed that the neurons stay viable for at least one hour after application of the mono-halomethane. However, a moderate, but consistent, irreversible decrease in synaptic excitability was observed. The intracellular recordings indicate that this may be attributed to a decrease in excitatory postsynaptic potentials. No effects were observed at 0.7 mM methyl bromide. Bromide, in a dose-dependent, partly reversible manner (during one hour), produced a similar decrease in excitability. Quantitatively, the action of bromide at 0.5 mM resembled the one seen with methyl bromide at the concentration of 1.4 mM. Since methyl bromide did not induce electrophysiologic changes consistent with evidence of neurotoxicity during one hour of observation it is concluded that it lacks immediate toxic effects on hippocampal rat neurons. Its neurotoxicity may be entirely due to metabolites or other indirect effects. The slight decrease in excitability may be due to the effect of bromide that is set free as tissue proteins and other cell molecules are methylated.

Animals↗
PubMed1998

Protective Effect of Broccoli, Onion, Carrot, and Licorice Extracts against Cytotoxicity of N-Nitrosamines Evaluated by 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium Bromide Assay.

The protective effect of nine fruit and vegetable aqueous (H(2)O) and ethanolic (EtOH) extracts against the cytotoxicity of N-nitrosodimethylamine (NDMA), N-nitrosopyrrolidine (NPYR), N-nitrosodibutylamine (NDBA), and N-nitrosopiperidine (NPIP) was evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The fruit extracts under investigation did not show a protective effect against any N-nitrosamines tested. Four vegetable extracts exhibited a protective effect (to 100% of survival) and a stimulation of cellular proliferation (>100% of survival) in decreasing order against NDMA and NPYR: broccoli(EtOH) > onion(H2O) > carrot(EtOH) > onion(EtOH) > licorice(H2O). Decreasing orders against NDBA and NPIP were, respectively, broccoli(EtOH) > licorice(H2O) > carrot(EtOH) > onion(EtOH) and broccoli(EtOH) > carrot(EtOH) > licorice(H2O) > onion(EtOH). Thus, broccoli(EtOH) extract (19-20 mg/mL) showed greater protective effect and stimulation of cellular proliferation (160% of survival) against all N-nitrosamines studied than the other vegetable extracts tested.

Journal Article↗
PubMed1998

Transcription and weak expression of HLA-DRB6: a gene with anomalies in exon 1 and other regions.

HLA-DRB6 is one of the human major histocompatibility complex (MHC) genes present in DR1, DR2, and DR10 haplotypes (approximately 26% of individuals). It shows several anomalies in human and non-human primates, including exon 2 stop codons (non-randomly grouped between codons 74 and 94) and a promoter region, and an exon 1 coming from an inserted retrovirus. It has been shown that not only chimpanzee but also human Mhc-DRB6 lack the usual 3' untranslated (UT) polyadenylation signal, and in the present work it was found that the human DRB6 gene coming from an HLA-DR2 haplotype is effectively transcribed after transfection in mouse L cells, and that HLA-DRB6 molecules may be expressed on the cell surface. DRB6 transcription level is remarkably lower in human than in chimpanzee. Moreover, their exons 1 (both taken from the 3'LTR region of a mammary tumor retrovirus) are also different; this shows that these viral insertions may be an important mechanism for different evolutionary changes in orthologous genes of different species. The pathways by which DRB6 molecules may be expressed on the membrane are unclear but other examples of truncated protein expression have also been described, even within the human major histocompatibility complex (i. e., in HLA-G). Finally, the presence of mature HLA-DRB6 mRNA molecules supports the notion that splicing may take place even in the absence of a canonical 3'UT polyadenylation signal.

Amino Acid Sequence↗
PubMed1998

Lack of HLA-G soluble isoforms in Graves-Basedow thyrocytes and complete cDNA sequence of the HLA-G*01012 allele.

The presence of HLA-G mRNA has been studied in thyroid follicular cells from autoimmune patients with Graves' disease. Investigating the possible role of the expression of the HLA-G gene in tissue inflammation, we have found four of the six HLA-G mRNA isoforms described: G1, G2, G3 and G4, but not the soluble ones G5 and G6. Soluble G isoforms may be responsible for inducing tolerance and inflammation control and their absence in autoimmune thyroid follicular cells may induce failure of such control. In addition, the complete coding sequence of HLA-G*01012 has been obtained from thyrocytes and it shows only four synonymous changes with respect to the HLA-G*01011 allele; this further supports the existence of an evolutionary pressure for invariance on HLA-G genes.

Alleles↗
PubMed1998

Hygiene behaviour in rural Nicaragua in relation to diarrhoea.

BACKGROUND: Childhood diarrhoea is a leading cause of morbidity and mortality in Nicaragua. Amongst the risk factors for its transmission are 'poor' hygiene practices. We investigated the effect of a large number of hygiene practices on diarrhoeal disease in children aged <2 years and validated the technique of direct observation of hygiene behaviour. METHODS: A prospective follow-up study was carried out in a rural zone of Nicaragua. From the database of a previously conducted case-control study on water and sanitation 172 families were recruited, half of which had experienced a higher than expected rate of diarrhoea in their children and the other half a lower rate. Hygiene behaviour was observed over two mornings and diarrhoea incidence was recorded with a calendar, filled out by the mother, and collected every week for 5 months. RESULTS: Of 46 'good' practices studied, 39 were associated with a lower risk of diarrhoea, five were unrelated and only for two a higher risk was observed. Washing of hands, domestic cleanliness (kitchen, living room, yard) and the use of a diaper/underclothes by the child had the strongest protective effect. Schooling (>3 years of primary school) and better economic position (possession of a radio) had a positive influence on general hygiene behaviour, education having a slightly stronger effect when a radio was present. Individual hygiene behaviour appeared to be highly variable in contrast with the consistent behaviour of the community as a whole. Feasible and appropriate indicators of hygiene behaviour were found to be domestic cleanliness and the use of a diaper or underclothes by the child. CONCLUSION: A consistent relationship between almost all hygiene practices and diarrhoea was detected, more schooling producing better hygiene behaviour. The high variability of hygiene behaviour at the individual level requires repeated observations (at least two) before and after the hygiene education in the event one wants to measure the impact of the campaign on the individual.

Adult↗
PubMed1998

Gonadotropin-releasing hormone increases ability of the spermatozoa to bind to the human zona pellucida.

Sperm-zona pellucida binding, a crucial step in the process of fertilization, takes place in vivo in the upper portion of the fallopian tube. The presence of GnRH-like peptides in the female and the male genital tract has been described. In this work, the effect of GnRH and related peptides upon sperm-zona pellucida binding ability was studied. Sperm aliquots, capacitated for 4.5 h, were incubated for 5 min with saline (control) or 20 nM of GnRH, C-terminal (1-5) or N-terminal (5-10) fragments of GnRH, Substance P, dynorphin, bombesin, or mixed GnRH (a synthetic peptide with the same amino acids as GnRH but in different order). Sperm were also incubated with the GnRH antagonist Ac-3,4-dehydro-Pro1, -p-fluoro- D-Phe2, D-Trp3,6-LHRH, alone or before adding GnRH. The sperm were then tested using the hemizona assay. After 10 min, the number of zona-bound sperm was determined. In addition, the effect of GnRH upon the acrosome reactions, sperm movement characteristics, and sperm-zona collisions was evaluated. Sperm treated with GnRH bound in higher numbers to the zona than did control sperm (p < 0.005). The GnRH fragments, the GnRH antagonist, and related peptides did not have any effect on sperm-zona interaction; however, the GnRH antagonist totally blocked the stimulatory effect of GnRH. GnRH did not affect the percentage of acrosome-reacted sperm, pattern of sperm movement, or frequency of sperm-zona collisions. I suggest that the increased ability of the sperm to bind to the zona may be due to exposure and/or change of affinity of zona receptors on the sperm plasma membrane.

Acrosome↗
PubMed1998

Developmental hematopoiesis.

Hematopoiesis is a developmental process that evolves throughout the lifespan of an individual. Most work in the field has focused on events occurring in the adult bone marrow (BM). In the embryo, blood and endothelial cell generation begins very early after gastrulation, in defined intraembryonic mesodermic sites. Recent multidisciplinary studies, taking advantage of classic embryological and gene targeting technology in various species, have provided a new image of embryofetal lymphohemopoiesis, which includes the suggestion of developmental compartmentalization or waves. The first hematopoietic stem cells (HSC) migrate further and home in an ordered sequence of supporting microenvironments depending on scarcely known molecular requirements. These early hematopoietic progenitors show important differences in their cell biology and differentiation potentialities with respect to those present in adult stages; this fact, together with specific microenvironmental influences, define a process that diverges significantly from that occurring in the BM. Here, we update the latest developments in the field, the new understanding of lymphohemopoiesis in prenatal life, and the novel questions that this emerging paradigm is producing.

Cardiovascular System↗
PubMed1998

Use of intrauterine contraceptive devices in nulliparous women: personal experience over a 12-year period.

OBJECTIVE: To evaluate the use of intrauterine contraceptive devices (IUDs) in nulliparous women compared to their use in parous women. METHODS: A comparative cross-sectional study was carried out to determine the reasons for removal of IUDs inserted between 1985 and 1996 in a sample of 227 nulliparous women and 2080 parous women. The statistical analysis was performed using the chi 2 test; the differences were considered to be significant when p < 0.05. RESULTS: The reasons for removal of IUDs in the two groups were: expiry, 49.1% in the nulliparous group vs. 48.2% in the parous group; planned pregnancy, 21.7% vs. 15.4%; accidental pregnancy, 4.8% vs. 6.3%; expulsion, 1.6% vs. 5.1%; pelvic inflammatory disease, 1.6% vs. 1.1%; pain and/or bleeding, 14.5% vs. 10.2%; other, 6.4% vs. 6.3%; vasectomy or tubal sterilization, 0% vs. 7%. CONCLUSION: Our data suggest that nulliparity is not a contraindication for the use of an IUD, and that the use of an IUD in nulliparous women is as safe and effective as in parous women.

Adolescent↗
PubMed1998

[Low energy transcatheter atrial defibrillation in one patient with refractory atrial fibrillation].

Most cases of atrial fibrillation are converted with antiarrhythmic medications or external electric defibrillation. However, in some refractory patients, an internal transcatheter defibrillation must be attempted. We report a 50 years old male with an atrial fibrillation of one year duration that was refractory to pharmacological treatment and in whom external cardioversion was unsuccessful. After the application of a bifasic shock of 10 joules between a catheter in the right atrium and another one located at the coronary sinus, the patient was converted to sinus rhythm. At two months of follow up, the patient continues in sinus rhythm.

Atrial Fibrillation↗
PubMed1998

[Implantable defibrillators in the management of malignant ventricular tachyarrhythmias. Experience at the Arrhythmia National Center].

BACKGROUND: Implantable defibrillators are the most effective means to prevent sudden death in patients with malignant ventricular tachyarrhythmias. The availability of this type of devices is limited in Chile, due to their high price. AIM: To report the first patients treated with implantable defibrillators in our hospital. PATIENTS AND METHODS: Nine males and one female aged 13 to 65 years old are reported. Three presented with ventricular fibrillation (presenting out of the hospital in three) and the rest had ventricular tachycardia resistant to drugs or radiofrequency ablation. RESULTS: All implants were performed using intracardiac electrodes. The generator was implanted in the pectoral region in nine and in the abdomen in one. A successful defibrillation was obtained with less than 15 J in four patients, with 20 J in three and with 24 J in three. There were no complications during the procedure. After a 12 months follow up, four patients have been treated by the implantable device. One of these subjects had a ventricular fibrillation in two occasions. One patient died of a bronchopneumonia two years after the implant. CONCLUSIONS: Implantable defibrillators are an effective therapy for the treatment of malignant ventricular arrhythmias with a high risk of sudden death.

Adolescent↗
PubMed1998

[Sudden death due to recuperated ventricular fibrillation: Brugada syndrome?].

We report a 47 years old male who was recuperated from a sudden death, and in whom the cardiological assessment showed a right bundle branch block and a fluctuating ST segment elevation V1 to V3. During the electrophysiological study, a polymorphic tachycardia and a ventricular fibrillation were induced. Procainamide administration enhanced ST segment alterations in right precordial leads, and isoproterenol normalized the EKG. All these disturbances are similar to the condition described by Brugada brothers. The patient was treated with an internal implantable defibrillator, without the use of antiarrhythmic drugs and is well after four months of follow up.

Bundle-Branch Block↗