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R Romero

Publications and source records attributed to R Romero.

At least 181 records · Page 10Linked to original sources
PubMed1999

Oxytocin activates mitogen-activated protein kinase and up-regulates cyclooxygenase-2 and prostaglandin production in human myometrial cells.

OBJECTIVE: The objective of our study was to test the hypothesis that oxytocin promotes prostaglandin production by up-regulating cyclooxygenase-2 via activation of mitogen-activated protein kinase cascade in human myometrial cells. STUDY DESIGN: Confluent cultures of human myometrial cells obtained from uterine specimens of premenopausal women undergoing hysterectomy were serum starved for 48 hours before oxytocin stimulation. Prostacyclin levels, as 6-keto-prostaglandin F(1) (alpha), were measured by radioimmunoassay, and the cellular cyclooxygenase-2 protein content was determined by Western blot. Mitogen-activated protein kinase activity was assessed by measuring the phosphorylation of myelin basic protein. RESULTS: In a time- and dose-dependent manner oxytocin promoted prostacyclin production in human myometrial cells. Maximal responses were observed after 8 hours of stimulation at a dose of 100 nmol/L. This effect was mainly due to the expression of cyclooxygenase-2 protein. Within 5 minutes oxytocin significantly stimulated mitogen-activated protein kinase, as compared with the expression in untreated controls. The maximal increase in enzyme activity (2.5-fold) was obtained at 45 minutes. A selective inhibitor of mitogen-activated protein kinase activation (PD98059), as well as herbimycin, a tyrosine kinase inhibitor, and the transcriptional blocker actinomycin D, suppressed oxytocin-induced cyclooxygenase-2 expression and prostacyclin production. The stimulatory action of oxytocin was also sensitive to inhibition by pertussis toxin but appeared to be independent of protein kinase C activation. CONCLUSION: Our data indicate a largely unrecognized signal transduction mechanism for oxytocin, involving G-protein-coupled activation of mitogen-activated protein kinase and cyclooxygenase-2 gene expression, leading to increased prostaglandin production in human myometrial cells. This signaling pathway complements the rapid activation of the phosphoinositide cycle and may be responsible for sustained release of prostaglandins in uterine tissues, promoting labor and parturition.

Blotting, Western↗
PubMed1999

The nuclear transcription factor NF-kappaB mediates interleukin-1beta-induced expression of cyclooxygenase-2 in human myometrial cells.

OBJECTIVE: Up-regulation of prostaglandin production by gestational tissues in the setting of intrauterine infection has been implicated as an important contributor to preterm labor and parturition. In this study we investigated the possible role of the nuclear transcription factor NF-kappaB in interleukin-1 signaling, leading to the expression of cyclooxygenase 2 and prostaglandin production in human myometrial cell cultures. STUDY DESIGN: Human myometrial smooth muscle cells from an immortalized line were used as a model system between passages 20 and 35. Growth-arrested cell cultures were stimulated with human recombinant interleukin 1, and the activation of NF-kappaB was assessed by the degradation of the inhibitory protein IkappaB-alpha (Western analysis), as well as by nuclear binding of NF-kappaB by using an electrophoretic mobility shift assay. The abundance of cyclooxygenase-2 messenger ribonucleic acid and protein was measured by Northern and Western analyses, whereas prostaglandin (prostaglandin I(2 ) and prostaglandin E(2 )) production was determined by specific radioimmunoassays. RESULTS: Within 15 minutes of stimulation with interleukin 1, 90% of IkappaB-alpha was degraded. This was temporally associated with nuclear translocation and binding of NF-kappaB. Within 30 minutes, cyclooxygenase 2 messenger ribonucleic acid appeared, with steady-state levels increasing up to 4 hours. This was followed by an up to 80-fold increase in cyclooxygenase 2 protein and a corresponding time-dependent increase in prostaglandin production. When IkappaB-alpha degradation was blocked with calpain I inhibitor, NF-kappaB translocation, cyclooxygenase 2 messenger ribonucleic acid and protein expression, and prostaglandin synthesis were also inhibited. CONCLUSION: Stimulation of human myometrial cells with interleukin 1 leads to rapid activation of the transcription factor NF-kappaB, which is functionally linked to the expression of cyclooxygenase 2 messenger ribonucleic acid, protein, and prostaglandin synthesis.

Blotting, Northern↗
PubMed1999

Atherosclerosis profile and microalbuminuria in essential hypertension.

Whether microalbuminuria (MA) is the result of intrarenal hemodynamic changes induced by increased systemic blood pressure (BP) or a marker of capillary leakiness at the glomerular level that reflects more generalized atherosclerotic vascular damage is still debated. To address this question, 319 patients without diabetes, 154 men and 165 women aged 57 +/- 8.6 years (range, 37 to 73 years), but with essential hypertension (EH) never treated with drugs were enrolled onto the study. Using a multiple linear regression analysis, we analyzed the prevalence of MA and its relationship with BP level as well as with other risk factors for the development of atherosclerosis. MA was present in 40% of the population studied. A univariable analysis of ambulatory BP monitoring measurements showed that only 24-hour systolic BP (P = 0.04), daytime systolic BP (P = 0. 02), and 24-hour daytime and nighttime systolic BP load (P < 0.01) predicted the presence of MA, whereas all BP variability parameters significantly predicted it. Multivariable analysis showed that only a positive family history of hypertension (P < 0.001), BMI (P < 0. 001), glucose (P < 0.001), and 24-hour systolic BP coefficient of variation (P < 0.001) independently predicted MA. In summary, the prevalence of MA in our group of patients with EH was high, presumably as a consequence of the older mean age of the population and the selection criteria. Besides being a marker of concomitant cardiovascular damage, MA was associated with a worse pattern of atherosclerotic risk factors. Although its pathophysiological meaning remains to be completely clarified, MA seems to be more related to other atherosclerosis risk factors and presumably reflects a more diffuse vascular injury.

Adult↗
PubMed1999

Renal artery rupture secondary to pretransplantation Candida contamination of the graft in two different recipients.

Infected graft transplantation is an unwelcome complication that may lead to serious consequences in the immunosuppressed host. It can be caused by infection of the donor or by contamination of the organ during harvest, preservation and handling, or at transplantation. With current donor evaluation protocols, the risk of transmitting infections by exogenous contaminated grafts seems to be more frequent than true donor-transmitted infections. Nevertheless, although rare and usually free of clinically significant sequelae, if contamination is by some virulent organisms such as Staphylococcus aureus, gram-negative bacilli, or fungi, severe complications may occur. We report the clinical outcome of liver, heart, and kidney recipients from a single donor. Both renal allografts had to be removed because of renal artery rupture secondary to Candida albicans infection. Careful donor evaluation before transplantation, unusually early presentation of mycosis leading to anastomotic renal artery disruption, the histopathologic findings of the grafts, and the absence of Candida infection in the liver and heart recipients make us believe that exogenous contamination of the grafts occurred during donor procedure, kidney processing, or at transplantation. In summary, because infected grafts can lead to serious complications, besides careful donor screening, it is important to achieve early recognition of contaminated organs by culturing the perfusate to start specific antibiotic or antifungal therapy after transplantation if necessary and avoid the rare but, in this case, fatal consequences of these infections.

Adolescent↗
PubMed1999

Inclusion of entire pancreas in the composite liver and intestinal graft in pediatric intestinal transplantation.

An entire pancreatico-duodenal complex was included in the liver and intestinal graft in eight children who received small-size grafts. This method showed several advantages compared to the traditional approach. They included reducing time for graft preparation by eliminating donor pancreas resection, no necessity of biliary reconstruction and leaving natural tissue support for blood vessels. The method was not associated with an increased risk of complications such as pancreatitis or rejection. It should be considered in pediatric liver and intestinal transplant recipients who require small-size grafts.

Age Factors↗
PubMed1999

Allogeneic bone marrow transplantation vs chemotherapy for the treatment of childhood acute lymphoblastic leukaemia in second complete remission (revisited 10 years on).

In 1989 we carried out a trial comparing allogeneic BMT to chemotherapy (CT) in 76 children with relapsed acute lymphoblastic leukaemia (ALL). Ten years on we have clinically revised outcome to firmly establish the role of each treatment, to analyse the importance of length of first remission and to provide long-term actuarial results for disease-free survival (DFS) and relapse rate in each group. For 21 patients within the transplantation group, probability of DFS and relapse are 42.8 +/- 10.8% and 40.2 +/- 11.7% (s.e.), respectively. In the chemotherapy group, probability of DFS is 10.0 +/- 4.74% (P = 0.001) and probability of relapse 87.5 +/- 5.2% (P = 0.0004). These results strongly reflect those at initial analysis, confirming a key role of BMT in the management of ALL in second remission. Moreover, on univariate analysis only two factors influenced DFS: treatment group and length of first complete remission (less or more than 30 months from first CR). Thus, it seems clear that the best therapeutic option in early relapse is BMT, whereas DFS in late relapse is at the limit of significance (P = 0.07), with a higher relapse rate in the CT group. Although encouraging results using intensified rotational combination chemotherapy have been published, prospective randomised studies are needed to assess with certainty the best therapeutic option in these patients.

Adolescent↗
PubMed1999

Multiple roles for heparin-binding epidermal growth factor-like growth factor are suggested by its cell-specific expression during the human endometrial cycle and early placentation.

Embryonic expression of the epidermal growth factor (EGF) receptor as well as embryonic and steroid-dependent uterine secretion of its ligand, heparin-binding EGF-like growth factor (HB-EGF), are temporally associated with the period of blastocyst implantation. We examined the temporal cell type-specific expression of HB-EGF in human endometrium during the menstrual cycle by immunohistochemistry and in situ hybridization. Early first trimester implantation sites were also examined to determine HB-EGF protein levels in decidual and fetal tissues. In the endometrial stroma, HB-EGF protein expression increased markedly during the late proliferative phase and then decreased in the early secretory phase. By contrast, luminal and glandular epithelial cells as well as blood vessel endothelium accumulated the protein between midcycle and cycle day 20, with peak expression observed during the period of uterine receptivity for implantation. HB-EGF expression decreased dramatically at the end of the cycle, before menses. Spatiotemporal expression of HB-EGF messenger ribonucleic acid demonstrated a similar pattern. During early pregnancy, HB-EGF immunostaining was noted in the decidua and in both villous and extravillous trophoblast populations. These findings suggest that HB-EGF promotes implantation and trophoblast invasion through paracrine and autocrine signaling as cells penetrate the stroma and displace the arteriole endothelium.

Adolescent↗
PubMed1999

Secondary hyperparathyroidism exacerbation: a rare side-effect of interferon-alpha?

Recombinant human interferon alpha (alpha IFN) is the only treatment with proven benefit for chronic hepatitis C virus (HCV) infection. Nevertheless its use in some susceptible individuals has led to the development or aggravation of different autoimmune conditions. We report the case of a 20 year old woman on peritoneal dialysis with chronic lobular hepatitis secondary to HCV infection who developed de novo psoriasis 9 months after starting treatment with alpha-IFN. In addition to psoriasis, alpha-IFN prescription was also concurrent with an unexpected and refractory secondary hyperparathyroidism exacerbation initially characterized by a marked reduction of serum calcium levels and a consequential increase of PTH. Both complications disappeared after drug withdrawal. The clinical sequence makes an alpha-IFN-induced autoimmune side effect the most plausible hypothesis. The case is discussed and some possible etiopathogenic factors are briefly reviewed.

Adult↗
PubMed1999

[Indications from the laparoscopic approach in pediatric urological surgery: our experience in 49 patients].

OBJECTIVES: To analyse the diagnostic and therapeutic potential of video-assisted laparoscopy in the urology paediatric pathology. We had analysed its indications and results, to measure in disminution of morbidity and hospital stay. PATIENTS AND METHODS: We are treated in our section of Paediatric Urology 49 patients during the period of June 1995 and December 1998, performing 51 laparoscopics procedures. The mean age was 8 years (2-16 years ago). The laparoscopic indications were diagnostic in 33 patients: intra-abdominal testes (n = 16), renal biopsy (n = 17), and terapeuthics in 16 patients (17 laparoscopics procedures): varicoceltomy (n = 7), orchiectomy (n = 1), closure peritoneal-vaginal duct (n = 2), retroperitoneal nephrectomy (n = 6), marsupilazation and omentoplastic in giant lymphocel renal post-transplantation (n = 2). RESULTS: The laparoscopic approach were effective in 100% of diagnostic procedures and 93.4% of therapeuticm procedures. Conversion in 2 cases were necessary to make renal biopsy (n = 1). We hadn't have postoperatives complications and the indices of intraoperative morbidity was of 2.4%. The mean hospital stay was 1.4 days. CONCLUSIONS: We believe that exist indications clinically stabilised of laparoscopic approach--diagnostic and therapeutic--in paediatric urology. There are others indications that its are consider anecdotal in the present but in immediately future these indications will be valid.

Adolescent↗
PubMed1999

[Thyroid tumors in childhood].

The thyroid pathology in the paediatric population represents 5% of the total and 1.2% only thyroid pathology correspond to the infantile solitary thyroid nodules. Most of them are asymptomatic and as only sign an increase of volume is observed in the neck. Always we have to ask about the family history because the possibility of medullary carcinoma related with multiple endocrine neoplasias should be investigated (a patient of our series). The thyroid tumor represents 0.5% of all the tumors and of these 10% is in younger than 21 years old. We present 13 patients with thyroid pathology that have required surgical treatment, since 1983 to 1997. Five papillary carcinomas (ages: 7 to 14 years old) that started with a cervical nodule, normal thyroid function and a case of medullary carcinoma, in a multiple endocrine neoplasia (MEN II 2A). In the 5 cases of carcinoma papillary we were carried out total thyroidectomy and later on, postoperative ablative dose of 131I was administered. In the case of the girl with medullary carcinoma was carried out a total tumorectomy and lymph node excision. Finally, seven patients with nodule thyroid were thyroid benign tumors (benign 6 adenomas and 1 cyst colloid, ages: 8 to 15 years old). In all of them we were carried out total surgical excision of the thyroid nodules. Our protocol of study of nodule thyroid includes: 1) thyroid gammagraphy to know the intensity of reception of the isotope; 2) cervical ultrasound; and 3) biopsy or cytopathology of fine needle aspiration of the thyroid gland in children that it dissuades to base the surgical strategy on this test.

Adenoma↗
PubMed1999

[Sigmoid neovagina: apropos of 2 cases].

The presence of ambiguous external genitals can be related with a number of nosologic entities. We can find the female form with hypertrophic clitoris and vaginal hypoplasia in a wide variety of phenotype presentations. We have two young girls with ambiguous external genitals, where we notice hypertrophic clitoris and vaginal hypoplasia, with the diagnosis of mixed gonadal dysgenesis and androgen insensitivity syndrome (Morri's Syndrome). They have been operated several times: gonadectomy, genitoplasty, vaginoplasty and mammoplasty. We have made a neovagina, using a segment of sigma and preserving the walls of the former vagina. The surgical technique we used, consisted in the abdominoperineal descent of the segment of sigmoid colon and anastomosis with the back wall of the former vagina and the perineum; after that, we split the intervaginal septum, linking these two structures and reaching a lonely introitus vaginae. The hormonal treatment for the girl with mixed gonadal dysgenesis with estrogen and progestogen induces normal menstruations; we only use estrogen for the patient with Morri's Syndrome. The histology showed that there were dysgenetic gonads in one of the patients and testicular tissue without gonadal elements. Both girls have had a good evolution, with no problems and an excellent aesthetic and functional result.

Adolescent↗
PubMed1999

[Extracorporeal respiratory assistance (ECRA): initial experiences in Spain].

UNLABELLED: The attendance respiratory extracorporeal (AREC) is an oxygenation form for membrane extracorporeal with flow tidal and veno-venous cannula described by Chevalier et al. in 1990. We present our clinical experience so much with AREC in system veno-venous flow tidal as veno-arterial. From october of 1997 until the present time we have treated three patients by means AREC, in two patients with veno-venous system and in one veno-arterial. In all the cases bomb Collin-Cardio has been used with bladder for flow tidal and membrane of oxygenation of 0.8 m2, being inserted a system of alternative clamp of the branches of the circuit. The system AREC has been used in two patients with congenial diaphragmatic hernia, right in a case and left in the other one. The gestational age was of 38 and 36 weeks with a weight of 3,200 and 2,900 grams. Both patients were remitted from other centers by failure of the conventional treatment. In both cases the indication of AREC was the sharp deterioration of the general state with failure of the conservative treatment, being the previous oxygenation index of 109 and 112. The third patient precised veno-arterial AREC for ventricular failure during the correction of the congenital heart disease, this patient was 5 month old and the weight was 5,000 grams. The duration of AREC in the cases of congenital diaphragmatic hernia was of 14 and 10 days. In a patient the diaphragmatic hernia was corrected at the 55 hours of being in AREC. In the second case the hernia had been surgical corrected in another center. The exit of AREC in both cases carries out after a discreet improvement of the lung function. Both patients died at the 24 and 48 hours of the decannulation for cerebral hemorrhage and respiratory failure. The third patient stayed stable in veno-arterial AREC during 4 days, with hemodynamic support of 130 ml/kg/min, retiring the support to present absence of cerebral activity. CONCLUSIONS: With the derived limitations of the extreme severity of the treated cases and the current phase of beginning of the AREC team, we think that it is a useful and available technique in our country, for the handling of patient with cardiorespiratory failure while waiting for improvement of their base pathology.

Age Factors↗
PubMed1999

Lymphedema and the nurse practitioner.

Lymphedema is not uncommon after breast cancer surgery or radiation therapy and can appear days or even years after the causative event. Unfortunately, it is often missed by health care professionals, and patients suffer needlessly. The author discusses the nurse practitioner's role in prevention, diagnosis, and treatment of this debilitating disorder.

Breast Neoplasms↗