Search PubMed⌕ Search

Biomedical subjects

R Romero

Publications and source records attributed to R Romero.

At least 217 records · Page 12Linked to original sources
PubMed1998

Rhinocerebral mucormycosis following donor leukocyte infusion: successful treatment with liposomal amphotericin B and surgical debridement.

A 24-year-old male developed cytogenetic relapse of chronic myeloid leukemia (CML) four years after allogeneic BMT. After a year of treatment with IFN-alpha, he achieved a partial cytogenetic response. Treatment with donor leukocyte infusions (DLI) was given (total dose 1 x 10(8) T lymphocytes/kg). Two months later, he developed acute GVHD (skin and liver), that improved with CsA and methylprednisolone and resulted in cytogenetic remission with complete donor chimerism. One month later he developed rhinocerebral mucormycosis and was successfully treated with surgical debridement and liposomal amphotericin B (total dose 12 g). This is the first case of mucormycosis described after DLI.

Adult↗
PubMed1998

Modulation by nitric oxide of gastric acid secretion in toads.

Nitric oxide (NO) is a novel chemical messenger that mediates a variety of biological actions. This study was undertaken to investigate the effects of NO on parietal cell function. The rate of [3H]arginine conversion to [3H]citrulline, a parameter of NO synthase activity, and NO formation (as NO2-), were inhibited by the NO synthase inhibitor, NG-nitro-L-arginine methyl ester (L-NAME), in a concentration-dependent manner in the non-stimulated toad gastric mucosa. This range of concentrations of L-NAME provoked stimulation of H+ secretion in a similar fashion, which was blocked by L-arginine but not by D-arginine. Pre-treatment with carbachol plus ethylene glycol-bis(beta-aminoethyl ether)-N,N,N',N'-tetra-acetic acid (EGTA) prevented the effect of L-NAME on H+ secretion and drastically reduced NO synthase activity. L-arginine had an inhibitory effect on H+ secretion in non-stimulated and carbachol-stimulated gastric mucosa, which was reversed by L-NAME. Carbachol and pentagastrin, but not histamine, significantly increased NO formation in the toad gastric mucosa. The results suggest that changes in NO synthesis in the gastric mucosa may modulate parietal cell function and that a calcium-dependent mechanism may be involved.

1-Methyl-3-isobutylxanthine↗
PubMed1998

Fosinopril ameliorates exogenous cholesterol-induced incipient glomerular lesions in obese Zucker rats. Effects on eicosanoid secretion.

BACKGROUND: To date, the role of dietary cholesterol as a risk factor for some diabetic nephrophathy, such as mesangial expansion and glomerular lesions, is unknown. Controversy also exists regarding the effects of prostaglandin-induced changes in glomerular haemodynamics on the appearance of glomerulosclerosis. METHODS: We have used obese Zucker rats (OZRs) as a model of early nephrophathy to evaluate the effect of hypercholesterolaemic diet on glomerular prostaglandin secretion and on the development of glomerular lesions. Due to the role of angiotensin II (Ang II) in glomerular haemodynamics, we have also evaluated its effects on glomerular eicosanoid secretion. Furthermore, as it has been suggested recently by clinical studies that angiotensin-converting enzyme inhibitors (ACEIs) reduce serum lipids associated with proteinuria, we have also evaluated the effect of the ACEI, fosinopril, both in vivo and in vitro, using 24 h glomeruli cultures. RESULTS: Results showed that a cholesterol-rich diet significantly increased serum cholesterol, proteinuria and glomerular eicosanoid secretion, and caused macrophage-ED1 cell deposits in the glomerular mesangium. Segmentary lesions only appeared in those rats with the highest percentage of glomerular xanthomatous (macrophage-ED1) cells. Ang II, per se, caused a marked rise in glomerular prosaglandin E2 and thromboxane B2. The inhibition of Ang II synthesis with fosinopril reduced all the parameters listed above, whereas Ang II (10(-6)M) increased the secretion of TxB2 and tended to increase PGE2 secretion in glomerular culture. CONCLUSIONS: In conclusion, exogenous cholesterol per se may contribute to nephropathy by increasing eicosanoid secretion, serum lipid profile, urinary protein excretion and the development of glomerular lesions. Fosinopril reduced all these parameters probably by its effects on Ang II.

Angiotensin-Converting Enzyme Inhibitors↗
PubMed1998

Voluntary ingestion of Cortinarius mushrooms leading to chronic interstitial nephritis.

'Magic mushrooms' ingestion among the drug-using population has become a popular cheap way to get hallucinogenic effects which is not free of complications. One of these is acute renal failure related to Cortinarius genus intake. This one greatly resembles 'magic mushrooms' and confusion is possible for inexperienced collectors. We report the case of a young male ex-drug addict who developed acute tubulointerstitial nephritis after voluntary ingestion of Cortinarius orellanus. The clinical picture was preceded by a long latency period, had an insidious course without any data of hepatoxicity and evolved to a chronic state. Renal biopsy showed nonspecific histopathological findings. In summary, it is important to bear this possibility in mind when facing an acute tubulointerstitial nephritis of unknown origin in a drug-taking patient.

Acute Kidney Injury↗
PubMed1998

[Role of gravidin, a phospholipase A2 inhibitor, in uterine contraction].

OBJECTIVE: What is the significance of gravidine, a phospholipase A2 inhibitor, in parturition? METHODS: Gravidine concentrations were measured in amniotic fluid obtained by transabdominal amniocentesis from women in labor at term and not in labor using a sensitive and specific ELISA. RESULTS: (1) Amniotic fluid gravidine concentrations were lower in the presence than in the absence of labor. (2) Gravidine concentrations in the amniotic fluid of the forebag were higher than in the amniotic fluid of the upper compartment. (3) There was a positive correlation between gestational age and amniotic fluid gravidine concentrations. (4) No such correlation could be demonstrated between cervical dilatation and amniotic fluid gravidine concentrations. CONCLUSION: These results suggest that gravidine may play a permissive role in the interplay with prostanoids in the mechanism of parturition.

Amniotic Fluid↗
PubMed1998

Metabolic index in peritoneal dialysis.

To define protein anabolism or catabolism in our patients we retrospectively studied the 24-hour balances (B24 h), dietary protein intake (DPI), anthropometric parameters [body mass index (BMI), tricipital skin fold thickness (TF), and muscular arm circumference (MAC), using the rating scheme: undernourished (U): percentile (pc) < 15; normal (N): pc > 15 to pc < 85; obese (O): pc > 85], and urea kinetics (protein equivalent of nitrogen appearance) [PNA = PCR according to the Gotch-Borah (G), Blumenkrantz (B), and Randerson (R) formulas]. Nitrogen-balance [N-B = DPI(N)-PNA(N)], metabolic ratio (MR = DPI/PNA), and metabolic index (MI = IDPI/nPNA) were calculated as metabolic indicators. There were 215 evaluations (B24 h) in 44 patients, of whom 29 were male and 15 female, 35 on continuous ambulatory peritoneal dialysis (PD), 9 on automated PD, age 58.2 +/- 15.6 years, followed-up for 15.3 +/- 10.2 months. Undernourished patients (BMI) showed higher N-B, MR, and MI irrespective of the formula used, but MR was only significant using the Blumenkrantz formula. For N-balance and metabolic index, analysis of variance (ANOVA) was significant with all formulas. The mean metabolic index (Randerson) in subgroups was: U: 1.09 +/- 0.27, n = 54; N: 0.90 +/- 0.25, n = 135; O: 0.87 +/- 0.27, n = 26 (ANOVA: P < 0.0001). The U-N and U-O subgroup comparison was significant (Newman-Keuls P < 0.01). We concluded that: (1) The metabolic index is more discriminating for protein metabolism than N-balance or metabolic ratio. (2) Most of the undernourished patients (BMI) are anabolic according to metabolic index and N-balance, and this indicates recovery. (3) Undernourished (low BMI) patients with metabolic index < 1 deserve special attention due to the risk of remaining malnourished.

Anthropometry↗
PubMed1998

Mesalazine-associated tubulo-interstitial nephritis in inflammatory bowel disease.

The 5-aminosalicylic acid (5-ASA) is currently the treatment of choice for patients with inflammatory bowel disease. It can be administered as sulfasalazine (5-ASA + sulfapyridine), mesalazine (5-ASA + resins or gels) and olsalazine (two molecules of 5-ASA). The recent trend has been to use formulations without sulfapyridine since they produce less side-effects although some cases of nephrotoxicity have been described. We report the case of a young female with Crohn's disease treated with mesalazine (400 mg every 8 hours) over a period of 12 months who developed acute interstitial nephritis. The characteristic features of renal function impairment were an insidious onset with non-specific laboratory data and progression towards a chronic state which partially improved with steroid treatment. In summary, it is important to bear this possibility in mind when confronted by any renal impairment which cannot be related to a relapse of inflammatory bowel disease. Renal function should be monitored routinely in patients receiving mesalazine at least during the first year of treatment and annually thereafter.

Adult↗
PubMed1998

Fetal Behavioral Development: Measurement of Habituation, State Transitions, and Movement to Assess Fetal Well Being and to Predict Outcome

> Objective: This paper describes the deliberations of an interdisciplinary group of clinical and basic scientists who met at the National Institute of Child Health and Human Development to discuss the potential role of fetal behavior in assessing fetal well being and predicting neonatal outcome. The conference focused on three aspects of fetal behavior: 1) habituation; 2) state transitions; and 3) movement. Methods: The participants consisted of 25 leaders in the fields of obstetrics, perinatal medicine, neonatology, developmental psychobiology, developmental neuroscience, developmental psychology, ethology, and mathematics. The meeting was divided into three parts. In each of these a plenary speaker (a recognized expert in his field) began the session with an overview of the scientific theme. Two respondents, with research expertise in fetal research (animal models or human fetuses) followed with remarks on the plenary talk and comments based on their own studies. At the conclusion of these comments, the participants met in small groups to discuss the plenary proceedings and their implications for assessing human fetal well being and predicting outcome. At the conclusion of the small group deliberations all of the participants reconvened in a plenary session. During this part of the meeting a rapporteur from each small group summarized their discussions. Results and Conclusions: 1) Fetal habituation: there was a general consensus that research on this aspect of fetal behavior may have a high payoff for assessing human fetal well being and predicting neonatal outcome. 2) Behavioral state transitions: participants agreed that transitions afford investigators with an indication of when (timing) and how (models) behavior changes within and between developmental periods. Knowledge of transitions during development allows for tracking of behaviors that may be necessary for the fetus to adapt to its in utero environment or prepare for its postnatal life. 3) Chaos theory and fetal movement: participants concluded that non-linear dynamics systems analysis models could be useful to analyze "noise" within a measurement system; better define time scales; and increase resolution and thereby better identify "signals."

Journal Article↗
PubMed1998

The role of antibiotic therapy in the prevention of prematurity.

Prematurity is the leading cause of perinatal morbidity and mortality in the industrial world, occurring in 4% to 9% of all deliveries, a rate that has remained unchanged during the past decades. Despite the relative minority of obstetric patients affected by this problem, prematurity is responsible for approximately 70% to 80% of perinatal morbidity and mortality corrected for congenital anomalies. To date, treatment modalities (tocolysis) that have been applied to patients who have preterm labor (PTL) and preterm premature rupture of membranes have been found to be of limited value in reducing both the rate of prematurity and of perinatal mortality and morbidity. A possible explanation for this failure in prevention of prematurity can be attributed to the poor understanding of the mechanisms of parturition in general and the pathophysiology of PTL in particular.

Anti-Bacterial Agents↗
PubMed1998

Mucormycosis and hemopoietic transplants.

Mucormycosis is becoming recognized as a serious complication in patients undergoing hemopoietic transplantation (HT), because it is a major cause of morbidity and mortality. In our institution 4 cases of mucormycosis in post-HT period among 345 patients undergoing HT were diagnosed between 1984 and 1997. We studies the clinical characteristics of these cases and we conclude that mucormycosis is not a common infection in patients undergoing HT but that it is followed by a high morbidity and mortality. Maintained neutropenia is the most important risk factor.

Adult↗
PubMed1998

Restoration of open reading frame resulting from skipping of an exon with an internal deletion in the COL7A1 gene.

Restoration of open reading frame resulting from exon skipping has been documented as a mechanism of rescuing an mRNA transcript containing mutations. In this study, we describe a mutation in a family with dystrophic epidermolysis bullosa consisting of a 16-bp deletion within exon 87 of the type VII collagen gene (COL7A1) and predicted to lead to a frameshift and downstream premature termination codon. Unexpectedly, mRNA analysis revealed instead that the intraexonic deletion led to skipping of exon 87 and subsequent restoration of the open reading frame. The phenotypes and patterns of inheritance observed in this family arise from three different mutations, all of which affect RNA processing. Restoration of open reading frame by exon skipping represents a previously undescribed mechanism of action of intraexonic deletion mutations.

Biopsy↗
PubMed1998

[Nutritional characteristics of a cookie formulated with bovine blood plasma as a main source of protein].

The nutritional characteristics of a cookie formulated with bovine plasma as main protein source was evaluated. Bovine plasma was mixed with wheat flour, sugar or salt, condiments and vegetable oil. The mix was placed in trays and baking at 120 degrees C during 1 hour. Moisture, fat, protein, carbohydrate, metabolizable energy, ash, iron, essential amino acids, essential fatty acids, apparent digestibility, protein efficiency ratio, acceptability and tolerance of the final product were determined. Results indicated that 100 g of the cookie have 5 g of moisture, 16 g of fat, 16 g of protein, 61.4 g of carbohydrate, 408.2 Kcal of metabolizable energy, 1.59 g of ash, 1.9 mg of iron and 6.59 g of essential amino acids. Polyunsaturated fatty acids are in higher amount than saturated fatty acids. Results also indicated that 100 g of cookie provide at least 20% of the daily energy requirements, 24% of the iron and between 30 to 50% of the daily protein requirements for children at school age. Its digestibility and PER, tested in rats, were of 88.4% and 2.32 respectively. Acceptability and tolerance, both tested in children, were 97% and 100% respectively. The protein cookie could be included as a protein and energy supply in school meals.

Amino Acids, Essential↗
PubMed1997

Evaluation of a displacement assay with tamoxifen as prognostic indicator in breast-cancer patients with estrogen-receptor-positive tumors.

A displacement assay with tamoxifen, based on the relative binding affinity of tamoxifen and estradiol for the estrogen receptor (ER), was proposed in 1990 as prognostic indicator for breast-cancer patients. Validation of its predictive results in relation to the outcome of 73 patients with ER+ tumors is analyzed. ER, progesterone receptor (PgR) determinations and other conventional prognostic factors in relation to the displacement assay, were considered. Displacement assay results allowed ER+ tumors to be grouped as displaceable (D) or weakly displaceable (WD), with the implication that D tumors should respond better to tamoxifen (Tam) administration. Survival and disease-free interval curves showed highly significant differences between patients with ER+ D and ER+ WD tumors. For survival, including all tumor stages, 73.9% of patients were alive at 9 years after surgery in the group with D tumors and 37.0% in the group with WD tumors (p < 0.005); relative contribution of the different stages is analyzed. Addition of axillary-node number increased the prognostic significance of displacement categories for survival and disease-free interval. PgR determination as another ER functional expression failed to show significant differences for survival and disease-free interval between ER+ PgR+ and ER+ PgR- tumors. Thus, results from the displacement assay and from PgR determinations reflect 2 independent ER functional expressions. Displacement assay data appear as reliable prognostic indicators of breast-cancer outcome, and contribute to more appropriate treatment decisions in this pathology.

Antineoplastic Agents, Hormonal↗
PubMed1997

Normal angiogram after myocardial infarction in young patients: a prospective clinical-angiographic and long-term follow-up study.

This is an observational study in which we compared the clinical characteristics and the long-term course of young patients having acute myocardial infarction and angiographically normal coronary arteries and young patients showing significant coronary artery disease. In 87 patients aged < or = 40 years who suffered an acute myocardial infarction, enrolled in a prospective study over a period of 6.5 years, coronary anatomy was determined by angiography within a month of admission. The risk factors, clinical data, ventricular function and the long-term outcome were compared between patients with normal angiograms (Group 1, n = 12) and patients with coronary artery disease (Group 2, n = 75). Patients in Group 1 had a lower number of risk factors associated with them (17% vs. 64% with > 1 risk factor, P < 0.005), were younger (32 +/- 5 vs. 36 +/- 4, P < 0.01), lighter smokers (25% vs. 55% for > or = 2 packs per day, P < 0.05), had less frequent hypertension (0 vs. 25%, P < 0.05), hypercholesterolemia (17% vs. 52%, P = 0.02) and had a lower mean total cholesterol level (201 +/- 42 vs. 245 +/- 60 mg/100 ml, P < 0.05) than patients in Group 2. They also had a more common onset of their infarction during heavy physical exertion (67% vs. 17%, P < 0.001). A history of previous myocardial infarction, infarct location, global left ventricular function and regional wall motion were similar in both groups. After a mean follow-up period of 41 +/- 23 months, no patient died or had a second myocardial infarction in Group 1, and 4 patients had died in Group 2. The appearance of angina, less frequent in Group 1 than Group 2, tended to correlate with the extension of the coronary artery disease. We concluded that young patients with myocardial infarction have good prognosis irrespective of the coronary anatomy, although patients with normal coronary angiograms had less risk factors and less frequent new ischaemic events.

Adult↗
PubMed1997

Intraoperative control by somatosensory evoked potentials in the treatment of cervical myeloradiculopathy. Results in 210 cases.

Somatosensory evoked potentials (SEPs) were used for continuous monitoring of 210 patients during anterior surgery for cervical myeloradiculopathy, to test how effectively they help avoid irreversible neurological damage during surgery. The pathologies differed in severity and were treated by diskectomy or by extended corporectomy using the Senegas technique. Intraoperative SEP changes were recorded in 84 patients (40%); in 13 (6.2%) of these, changes in SEP amplitude and latency were caused by mechanical stress. SEPs revealed transient episodes of regional ischaemia or neurophysiological anomalies during anaesthesia (mainly hypotension) in 27 patients (12.8%). The traces detected incipient and potentially dangerous mechanical pressure on, or metabolic anomalies of, the spinal cord during manipulation and placement procedures of spinal fixation devices. They were particularly sensitive indicators of ischaemia; one of the most common causes of irreversible injury. The traces of 44 patients (21.0%) improved markedly during surgery. There were no false-negatives in this series and, thanks to the fact that SEPs gave immediate warnings of incipient ischaemia to the surgical team, we had no case of irreversible medullary or nerve-root deficit.

Adult↗
PubMed1997

Cell-, tissue-, and position-specific monoclonal antibodies against the planarian Dugesia (Girardia) tigrina.

To obtain specific immunological probes for studying molecular mechanisms involved in cell renewal, cell differentiation, and pattern formation in intact and regenerating planarians, we have produced a hybridoma library specific for the asexual race of the fresh-water planarian Dugesia (Girardia) tigrina. Among the 276 monoclonal antibodies showing tissue-, cell-, cell subtype-, subcellular- and position-specific staining, we have found monoclonal antibodies against all tissues and cell types with the exception of neoblasts, the undifferentiated totipotent stem-cells in planarians. We have also detected position-specific antigens that label anterior, central, and posterior regions. Patterns of expression uncovered an unexpected heterogeneity among previously thought single cell types, as well as interesting cross-reactivities that deserve further study. Characterization of some of these monoclonal antibodies suggests they may be extremely useful as molecular markers for studying cell renewal and cell differentiation in the intact and regenerating organism, tracing the origin, lineage, and differentiation of blastema cells, and characterizing the stages and mechanisms of early pattern formation. Moreover, two position-specific monoclonals, the first ones isolated in planarians, will be instrumental in describing in molecular terms how the new pattern unfolds during regeneration and in devising the pattern formation model that best fits classical data on regeneration in planarians.

Animals↗