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L Espinosa

Publications and source records attributed to L Espinosa.

At least 37 records · Page 2Linked to original sources
PubMed1999

[The long-term behavior of the valve bladder as a function of the initial treatment and its effect on early kidney failure].

In approximately 25-40% of infants presenting with posterior urethral valves (PUV) renal insufficiency will develop before adolescence. In some these patients, renal dysplasia, bladder dysfunction and mismanagement may precipitate renal failure at even earlier age. The goals of this study were to determine whether long-term bladder dysfunction was more frequent in children who underwent early temporary pyelostomy than in those who underwent valve ablation, and to know if bladder dysfunction and mismanagement, in some patients, could be responsible of early renal failure. Urodynamic studies were performed in 59 boys with severe PUV divided into two groups based on initial treatment. A) Valve ablation (30 p.); B) Cutaneous pyeloureterostomy (29 p.). At the end of the study 22 boys had chronic renal failure. Of the 59 boys, 42% (25 p.) had bladders with overdistended or normal behaviour, 58% (34 p.) had bladder dysfunction (instability 37%, low compliance 15%, myogenic failure 5%). The 89% of low compliance bladders, 66% of myogenic failure and 23% of those with instability were in CRF. No difference at all was found in bladder function between boys treated as neonates by high diversion or valve ablation. Of the group in chronic renal failure (22 p.), only 7 patients (32%) had bladders with normal behaviour and in five of these patients a mismanagement was directly related with a quicker renal deterioration. The 58% of our boys with severe PUV have some type of bladder dysfunction. Neonatal pyelo-ureterostomy does not increase long-term bladder dysfunction. Surgical mismanagement should be added to bladder dysfunction as contributors to earlier renal failure.

Child, Preschool↗
PubMed1998

In vitro and in vivo reversal of cancer cell multidrug resistance by the semi-synthetic antibiotic tiamulin.

A large number of multidrug resistance (MDR) modulators, termed chemosensitizers, have been identified from a variety of chemicals, but most have been proven to be clinically toxic. Low concentrations of the pleuromutilin-derived semi-synthetic antibiotic tiamulin (0.1 to 10 microM) sensitized the three highly resistant P-glycoprotein (Pgp)-overexpressing tumor cell lines P388 (murine lymphoid leukemia), AS30-D (rat hepatoma), CEM (human lymphoblastic leukemia), and the barely resistant AS30-D/S cell lines to several MDR-related anticancer drugs. Flow cytometric analysis showed that tiamulin significantly increased the intracellular accumulation of daunomycin. When compared to reference modulating agents such as verapamil and cyclosporin A, tiamulin proved to be 1.1 to 8.3 times more efficient in sensitizing the resistant cell lines. Moreover, when given i.p. (1.6 microg/mg body weight), tiamulin increased the survival rate of adriamycin-treated mice bearing the P388/ADR25 tumor line by 29%. In the presence of an anticancer drug, tiamulin inhibited both ATPase and drug transport activities of Pgp in plasma membranes from tumor cells. Tiamulin is thus a potent chemosensitizer that antagonizes the Pgp-mediated chemoresistance in many tumor cell lines expressing the MDR phenotype at different levels and displays no toxic effects on contractile tissues at active doses, therefore providing the promise for potential clinical applications.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed1998

Human serine/threonine protein kinase EMK1: genomic structure and cDNA cloning of isoforms produced by alternative splicing.

The EMK (ELKL Motif Kinase) is a small family of ser/thr protein kinases involved in the control of cell polarity, microtubule stability and cancer. We have isolated several cDNA clones that encoded two isoforms of the human ser/thr protein kinase EMK1 (GDB symbol EMK1, alias ELKL motif kinase 1, and MARK2). These isoforms were characterized by the presence of a 162-bp alternative exon that gave rise to two forms, one containing the exon and the other one lacking it. Both forms were found to be coexpressed in a number of selected cell lines and tissue samples when analyzed by RT-PCR. By Northern blot, human EMK1 was shown to be encoded by a single mRNA ubiquitously expressed. We have reconstructed most of the genomic structure of EMK1 from the sequence of two human chromosome 11 cosmids deposited in databases, and showed that the gene is composed of a minimum of 16 small exons.

Alternative Splicing↗
PubMed1997

Primary sequence of the human, lysine-rich, ribosomal protein RPL38 and detection of an unusual RPL38 processed pseudogene in the promoter region of the type-1 angiotensin II receptor gene.

We have isolated a cDNA clone encoding the human ribosomal protein L38 (HSRPL38). The longest ORF of the cDNA predicts a lysine-rich small polypeptide identical to the rat RPL38 protein (100% identity), and sharing a 84% of identity to the tomato RPL38 protein sequence. Northern blot analysis of a number of epithelial cell lines showed that the HSRPL38 is encoded by a mRNA ubiquitously expressed. Southern blot analysis of human genomic DNA suggested that the RPL38 does not constitute a multigene family but it is encoded by a reduced set of active genes, among which we have also found a RPL38 processed pseudogene located in the promoter region of the human type-1 angiotensin II receptor gene. This RPL38 pseudogene is very unusual among processed pseudogenes in that the poly A tail and the entire 5'-UTR of the original RPL38 mRNA were deleted during the retrotransposition process.

Amino Acid Sequence↗
PubMed1997

Reduction of I(Ca,L) and I(to1) density in hypertrophied right ventricular cells by simulated high altitude in adult rats.

The present paper describes the effect of a simulated hypobaric condition (at the altitude of 4500 m) on morphological characteristics and on some ionic currents in ventricular cells of adult rats. According to current data, chronic high-altitude exposure led to mild right ventricular hypertrophy. Increase in right ventricular weight appeared to be due wholly or partly to an enlargement of myocytes. The whole-cell patch-clamp technique was used and this confirmed, by cell capacitance measurement, that chronic high-altitude exposure induced an increase in the size of the right ventricular cells. Hypertrophied cells showed prolongation of action potential (AP). Four ionic currents, playing a role along with many others in the precise balance of inward and outward currents that control the duration of cardiac AP, were investigated. We report a significant decrease in the transient outward (I(to1)) and in the L-type calcium current (I(Ca,L)) densities while there was no significant difference in the delayed rectifier current (I(K)) or in the inward rectifier current (I(K1)) densities in hypertrophied right ventricular cells compared to control cells. At a given potential the decrease in I(to 1) density was relatively more important than the decrease in I(Ca,L) density. In both cell types, all the currents displayed the same voltage dependence. The inactivation kinetics of I(to 1) and I(Ca,L) or the steady-state activation and inactivation relationships were not significantly modified by chronic high-altitude exposure. We conclude that chronic high-altitude exposure induced true right ventricular myocyte hypertrophy and that the decrease in I(to 1) density might account for the lengthened action potential, or have a partial effect.

Action Potentials↗
PubMed1997

The gift of time.

Explore the source record for details and available documents.

Father-Child Relations↗
PubMed1994

[The prognosis of patients with posterior urethral valves according to the initial treatment and their urodynamic behavior].

Long-term outcome of 35 boys with severe posterior urethral valves is reviewed, with intention to know if the course of renal function depended on initial treatment and bladder dysfunction. Diagnosis was established during the first month in 15 patients, before one year in 16 and later in 4. Surgical management was initially, upper urinary tract diversion (pyeloureterostomy) in 19 patients (group A) and valve ablation in 15 (group B). The average age for closure of temporary urinary diversion was 17 months. Follow-up ranged from 4-19 years (mean 8.3 years). Twenty one patients had a urodynamic study years after initial treatment and this study showed 8 normal bladder, 7 unstable and 6 non-compliant. In group A, at the end of study, 13 patients (70%) have a glomerular filtration of more than 80 ml/min/1.72 m2 while in group B only 6 (37.5%) and average height after treatment was higher in patients of group A. Noncompliant bladders had worst prognosis (66% renal failure) than unstable bladders (25%) and the prognosis was improved in these types of bladders when initial treatment was upper tract diversion. The results of our study suggest that in patients with severe posterior urethral valves, the renal function improved with early diversion (pyeloureterostomy) and irreversible bladder dysfunction worsen the prognosis in these patients.

Follow-Up Studies↗
PubMed1993

[Outcome of conservative treatment of high-degree vesicoureteral reflux].

We performed a retrospective study to evaluate the results of a nonsurgical approach of primary high grade vesicoureteral reflux (VUR). 241 patients (209 III and 32 IV) were reviewed during and average time of 9.4 years. 55% of them were under 6 months and 52% had bilateral reflux (50% III and 63% IV). During the observation period spontaneous resolution of reflux was observed in 126 (60%) with grade III at 5 years and 26% in patient with grade IV at 4 years. In both grades the duration of persistent reflux was analyzed using life-table method. When age at presentation was compared with duration of reflux there was a shorter time of reflux in those patients presenting from age 0 to 6 months. New renal scars developed in 5 patients during the period of observational therapy. We conclude that high grade VUR can resolve over a protracted interval. On basis of this analysis, we advocate the surgical correction in these patients after 5-year period to grade III and 2-year to grade IV.

Child↗
PubMed1993

[Usefulness of the API ZYM system for the identification of Legionella sp].

BACKGROUND: The identification of Legionella genus is usually difficult, time consuming, and expensive. We decided to study the usefulness of API-ZYM system (Biomerieux) for Legionella species identification. METHODS: A total of 96 strains (82 from Legionella genus and 14 from other bacterial genus) were included. We studied 19 different enzyme activities and we proceed following the manufacturers directions, with an incubation time for galleries of 4 hours at 37 degrees C. RESULTS: Seventeen out of the 19 enzyme activities were uniformly positive or negative for Legionella sp. Thus, the sensitivity of these activities was 100% in identifying Legionella sp. Valine and cystine-arylamidase gave variable reactions for Legionella sp. strains. When the results of these enzyme test were compared to those of the control strains (Haemophilus influenzae, Pseudomonas aeruginosa) we observed that alkaline phosphatase, esterase, esterase-lipase, acid phosphatase and naphthol-AS-BI-phosphohydrolase in one side and esterase, esterase-lipase and leucin-arylamidase in the other side were able to differentiate Legionella sp. strains from P. aeruginosa and H. influenzae, respectively. CONCLUSION: API SYM system is a simple, accurate and reproducible method for the identification of Legionella sp.

Bacterial Proteins↗
PubMed1992

[The use of molecular epidemiologic markers in the study of an epidemic outbreak of legionnaires' disease of nosocomial origin].

BACKGROUND: Epidemiological investigations of Legionella infections are based, since recently, on molecular techniques that are more sensitive and specific than phenotypic traits. We were interested in these methods for subtyping isolates of L. pneumophila serogroup 1 and confirm the epidemic spread of an outbreak of legionnaires' disease at the Universitary Hospital Germans Trias i Pujol (HUGTiP) in Badalona. METHODS: Environmental samples taken from domestic water, heating and cooling water systems and oxygen humidifiers were examined. Clinical and environmental isolates of L. pneumophila serogroup 1 were compared by analysis of genomic DNA by restriction endonucleases. RESULTS: We could found L. pneumophila serogroup 1 and 9 in domestic hot water and heating systems and L. micdadei in cooling water system. Cleavage of genomic DNA showed that all restriction fragment patterns coming from clinical and environmental isolates of L. pneumophila serogroup 1 were identical and different from isolates belonging to the same species and serogroup but coming from community area. CONCLUSIONS: Molecular analysis of clinical and environmental isolates of L. pneumophila serogroup 1 has allowed to identify a reservoir related to a nosocomial outbreak of legionnaires' disease at the HUGTiP, and a clonal population of L. pneumophila serogroup 1 in environmental samples genotypically identical to the clinical ones.

Cross Infection↗
PubMed1992

[The causes of mortality and prevalent pathology in children in Portugal--their evolution and an analysis of the current situation].

The author analyses the infant mortality rate amongst different age groups in Portugal, considering not only the regional variations but also its prenatal, neonatal, post neonatal, and children between 1-4 and 5-9 years components. The author takes in consideration other factors which enable one to attribute the principal causes of morbidity to each particular age group.

Adolescent↗
PubMed1991

Anemia of chronic renal failure: treatment with erythropoietin.

Twenty-three anemic children with end-stage renal failure (ESRD), aged 0.1-19.0 years (X +/- SD, 8.3 +/- 5.7 years), were treated with intravenous recombinant human erythropoietin (rHuEPO). Eleven were on conservative treatment and their estimated glomerular filtration rate (EGFR) was 11.8 +/- 3.8 ml/min/1.73 m2; 7 were on continuous ambulatory peritoneal dialysis (CAPD) and 5 on chronic hemodialysis. rHuEPO was given once a week in predialysis and CAPD children and thrice weekly in patients on hemodialysis. The initial dose of 50 U/kg/week was increased gradually up to a target hemoglobin of 10-12 g/dl. After 4.3 +/- 1.3 months of treatment, hemoglobin increased from 7.4 +/- 1.3 to 10.7 +/- 1.4 g/dl (p less than 0.001). An hemoglobin concentration of 11.4 +/- 0.9 g/dl was maintained with a rHuEPO dose of 289 +/- 86 U/kg/week. The response was similar in predialysis, CAPD, and hemodialysis children. No change in renal function was observed in predialysis children, EGFR being 11.8 +/- 3.8 and 10.8 +/- 1.7 ml/min/1.73 m2, before and after rHuEPO therapy. All children improved appetite, physical activity, and the sense of well-being. Four developed mild hypertension that was easily controlled with antihypertensive therapy. Heparin dose had to be increased during the hemodialysis sessions to avoid clotting of the filter. Serum calcium increased from 9.9 +/- 0.9 to 10.5 +/- 0.9 mg/dl (p less than 0.001). Serum aluminium levels also increased from 65 +/- 17 to 100 +/- 15 micrograms/l, p less than 0.01. A linear correlation (r = 0.58, p less than 0.01) between aluminium levels and rHuEPO dose was found.(ABSTRACT TRUNCATED AT 250 WORDS)

Anemia↗
PubMed1989

Continuous arteriovenous haemofiltration in children.

Continuous arteriovenous haemofiltration (CAVH) was used in 7 critically ill children: a premature neonate with hypervolaemia secondary to hydrops foetalis and six children aged 9 days to 7 years with acute oliguric renal failure. Biospal 0.5 m2, Renaflo 0.25 m2, Gambro 0.15 m2 and Amicon 0.015 m2 filters were used according to the weights and ages of the patients. Adequate removal of water and solutes was obtained in 6 patients. One of the patients with the smallest filter needed a change to a filter with a larger surface area to improve water and solute removal. Haemofiltration was maintained for between 17 hours and 31 days and was well tolerated. CAVH was discontinued because of recovery of renal function in three patients, improvement of the hypervolaemic state in one, death in three, and transfer to continuous ambulatory peritoneal dialysis because of chronic renal failure in one patient. CAVH is a useful technique for the treatment of acute renal failure and hypervolaemia in critically ill children.

Acute Kidney Injury↗
PubMed1989

[Posterior urethral valves: prognosis related to the initial surgical treatment].

Long-term outcome of 32 boys with severe posterior urethral valves is reviewed. Diagnosis was established during the first month of life in 14 patients, along the first year in another 14 and later in five. Surgical management was, initially, bilateral upper urinary tract diversion (cutaneous ureterostomy or pyelostomy) in 17 patients (Group A), and valve ablation alone or vesicostomy in 15 children (Group B). Eight months was the mean age of patients at initial surgery (40% before the first month of life). The average age for closure of the temporary urinary diversion was 17 months. Eleven patients underwent later unilateral nephrectomy and eighteen antireflux surgical procedures. Follow-up ranged from 1 to 15 years (mean 6 years). Fifteen patients have a Glomerular Filtration Rate (G.F.R.) of more than 80 ml./min./1.73 m2. Eleven (73%) of them underwent early upper urinary tract diversion, and the remaining four (27%) underwent valve ablation or vesicostomy. Two children among the 32 have developed end stage renal disease. Average height and weight posttreatment values were higher in those patients treated with ureterostomy or pyelostomy. The results of our study suggest that renal function improved in patients with early upper urinary tract diversion.

Child, Preschool↗