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E Rodriguez

Publications and source records attributed to E Rodriguez.

At least 163 records · Page 9Linked to original sources
PubMed1994

Effect of isoproterenol on the relationship between regional cyclic AMP and local coronary blood flow in the canine myocardium.

This study was designed to test in the dog heart the hypothesis that local levels of myocardial cyclic AMP (cAMP) would exhibit significant heterogeneity; that this heterogeneity would correlate with local coronary blood flow, and that this association would be increased with isoproterenol stimulation. Anesthetized open-chest dogs were studied during control (n = 7) or isoproterenol (0.5 micrograms/kg/min) infusion (n = 7) to test this hypothesis. Coronary blood flow was measured with radioactive microspheres, and cAMP was determined with a competitive binding assay using 3H-cAMP. Significant heterogeneity in cAMP existed during basal [592 pmol/g, within-animal coefficient of variation (100 x mean/SD) = 45.2%] and isoproterenol stimulated [872 (27.3%)] conditions. Method variability could account for only 28% of the total basal variability. No correlation between local blood flow [87 ml/min/100 g (12.9%)] and local cAMP was found under control conditions. Both coronary blood flow [206 (20.8%)] and cAMP levels increased significantly with isoproterenol stimulation. There was a significant correlation between normalized stimulated blood flow and cAMP: % flow = 0.39 (% cAMP) + 61.3 (r = 0.48, p < 0.0001). We conclude that significant heterogeneity in myocardial cAMP levels exists, and that this heterogeneity correlates with coronary blood flow heterogeneity during isoproterenol stimulation.

Animals↗
PubMed1994

Frequency of sister chromatid exchanges in humans at 14-16 week foetal stage and at birth.

In order to identify transplacental induced mutagenicity in humans the baseline frequency of sister chromatid exchanges (SCEs) in amniotic fluid cells (8.56 +/- 0.28 per cell) from 14 to 16-week-old foetuses as well as in peripheral blood lymphocytes (7.96 +/- 0.26 per cell) from newborns was determined. A group of twelve patients who were analysed both at 14-16 weeks gestation and at birth showed no SCE variations. These results suggest that foetal amniocytes and T lymphocytes from newborns present a similar sensitivity to the mutagenic activity of the thymidine analogue 5-bromodeoxyuridine employed in the sister chromatid differentiation.

Adult↗
PubMed1994

Amaurosis fugax as a symptom of carotid artery stenosis. Its relationship with ulcerated plaque.

Amaurosis fugax has frequently been related to carotid artery disease. In order to determine the relationship between amaurosis fugax and significant carotid artery stenosis, we prospectively studied 81 consecutive patients presenting to an ophthalmologist with this symptom. Neurologic and vascular evaluation with PPG and Duplex-scan were performed. A stenosis of greater than 70% was regarded as significant. DSA was performed in patients with significant stenosis (55 of 81). The presence of risk factors such as hypertension, diabetes, coronary artery disease, tobacco and hyperlipidemia was considered. Mean age was 64.96 years. There was a high prevalence of hypertension, smoking and previous CVA/TIAs. Patients with significant carotid stenosis were endarterectomized. Carotid atheromata plaques were classified in three groups: hemorrhagic plaque (5), dystrophic calcification (8) and ulcerated plaque (42). There was a high correlation (0.87) between ulcerated plaque and amaurosis fugax. We conclude that amaurosis fugax is an important symptom to allocate patients with high risk of carotid disease, specially carotid stenosis complicated with ulcerated plaque. Carotid duplex scan must be done if this symptom is present.

Aged↗
PubMed1994

Chromosomal aberrations in soft tissue tumors. Relevance to diagnosis, classification, and molecular mechanisms.

In recent years, significant progress has been made in identifying characteristic chromosomal rearrangements associated with several solid tumor types, notably sarcomas, a relatively rare subset of human cancer. Most sarcomas analyzed have been found to be characterized by recurrent chromosome translocations that are specific to histological types. We have reviewed published reports of chromosomal aberrations in benign and malignant soft tissue tumors and found an incidence of specific translocations in these neoplasms that ranged from 20% to 93% within histological tumor types. Identification of recurrent chromosomal abnormalities in benign tumors has resulted in a reappraisal of the general concept that benign tumors have a normal (diploid) chromosome constitution. The variety of recurrent changes present in the different tumor types attests to the cytogenetic diversity inherent in these tumors. The chromosomal rearrangements in each of the tumor types were unique and did not correspond to cancer-associated aberrations known from other solid or hematopoietic malignancies. Cytogenetics thus provides an essential adjunct to diagnostic surgical pathology in the case of malignant soft tissue tumors, which often present substantial diagnostic challenges. In addition, it represents another approach to determine the histogenetic origin of some tumors and identifies sites of gene deregulation for molecular analysis. Indeed, recent molecular analyses of several sarcoma-associated translocations have identified novel genes and novel mechanisms of their dysregulation.

Chromosome Aberrations↗
PubMed1993

Molecular cytogenetic analysis of i(12p)-negative human male germ cell tumors.

The i(12p) chromosome has been shown to characterize more than 80% of male germ cell tumors (GCTs) and is an important diagnostic marker. Although recent cytogenetic analyses of GCTs have defined nonrandom chromosome abnormalities in these tumors, no attempt has so far been made to compare i(12p)-positive and -negative tumors in terms of their cytogenetic, histologic, and clinical features. During a 5-year period, we have ascertained 202 GCTs, of which 117 had clonally abnormal karyotypes. Among the latter, 91 had one or more copies of i(12p), whereas 26 lacked an i(12p). We report here the karyotypic analysis of these 26 i(12p)-negative GCTs. In this group, nonrandom sites of chromosomal rearrangements included 12p13 (9/26) and 1p11-q11 (5/26). Comparison of the cytogenetic features of i(12p)-negative tumors with i(12p)-positive tumors revealed the only significant difference to be rearrangements affecting 12p13 in the former (35%) as compared to their absence in the latter (3%). Hybridization of metaphase preparations of 9 i(12p)-negative tumors with a chromosome 12 painting probe and with a microdissected 12p painting probe revealed extra copies of chromosome 12 segments incorporated into marker chromosomes whose composition could not otherwise be resolved by banding analysis; all were shown to be derived from 12p. These data demonstrate that both i(12p)-negative and -positive groups are characterized by an increased copy number of 12p, which is consistent with a lack of significant clinical or biological difference between them. An increased 12p copy number thus is a specific aberration of significance to the development of germ cell tumors.

Chromosome Aberrations↗
PubMed1993

Effect of isoproterenol on coronary blood flow and signal transduction responses in thyroxine-treated rabbit hearts.

This study examined the hypothesis that treatment with thyroxine (T4) would alter the coronary blood flow and signal transduction responses of the rabbit heart. T4 was administered for 16 days by subcutaneous time-release pellets (3 mg/kg/day) in 3 kg New Zealand white rabbits. Four groups of anesthetized open-chest rabbits (control, control+isoproterenol (ISO, 0.5 microgram/kg/min for 15 min), T4, and T4 + ISO) were used to determine coronary blood flow (radioactive microspheres), cyclic AMP content (competitive binding), low Km cyclic-AMP-phosphodiesterase activity (cyclic AMP-PDE, conversion of 3H-cyclic AMP to 3H-AMP) and beta-adrenoceptor number and affinity (125I-iodocyano-pindolol). Coronary blood flow was increased from control by ISO from 167 +/- 59 to 354 +/- 157 ml/min/100 g. T4 did not cause cardiac hypertrophy, but increased baseline coronary blood flow to 269 +/- 115 ml/min/100 g. The ISO response was attenuated in terms of blood flow (448 +/- 118) and heart rate with T4. Beta-adrenoceptor numbers increased significantly from 65.7 +/- 9.2 to 81.9 +/- 4.4 fmol/mg protein, while neither soluble (126 +/- 39 vs 119 +/- 15 pmol/mg protein/min) nor particulate cyclic AMP-PDE activity were different between control and T4 animals. Cyclic AMP content was increased from control by both ISO (779 +/- 239 to 1371 +/- 672 pmol/g) and T4 (1143 +/- 244). T4 animals showed a smaller increase in cyclic AMP following ISO (1391 +/- 261). There was not a significant difference between the control and T4 group cyclic AMP level following ISO. Thus, despite increased beta-adrenoceptor numbers, there was a diminished responsiveness of heart rate, coronary blood flow and cyclic AMP levels to isoproterenol in the T4-treated rabbit hearts.

3',5'-Cyclic-AMP Phosphodiesterases↗
PubMed1993

Bioimpedance measurement of body water correlates with measured volume balance in injured patients.

Bioimpedance technology is being used increasingly to determine drug volume of distribution, body water status, and nutrition repletion. Its accuracy in patients experiencing large volume flux is not established. To address this, we undertook this prospective study in 54 consecutive seriously injured adults who had emergency celiotomy soon after arrival in the emergency department. Bioimpedance measurements were obtained in the emergency department before the patient was transported to the operating room, on completion of celiotomy, and 24 hours and 48 hours after celiotomy. Bioimpedance measurements of body water were compared with measured fluid balance. If insensible losses are subtracted from measured fluid balance, the percentage of body weight, which is body water determined by bioimpedance, closely follows fluid flux. This study supports the use of bioimpedance measurements in determining total body water even during periods of surgery, blood loss, and vigorous resuscitation.

Abdomen↗
PubMed1993

Relationship between local myocardial adenylyl cyclase activity and local coronary blood flow in the dog heart.

1. This study tested the hypothesis that heterogeneity of myocardial adenylyl cyclase activity exists and contributes to the heterogeneity of blood flow in canine myocardium, in which flow varies in different areas at any one moment or in a single area at different times. 2. Tissue adenylyl cyclase activity was measured simultaneously with coronary blood flow in the left ventricle of eight anaesthetized open-chest dogs. Coronary flow was measured using radioactive microspheres under control conditions and after sympathetic stimulation. The ventricle was cut into 15 subepicardial and 15 subendocardial sections in which both flow and adenylyl cyclase (basal and forskolin-stimulated) activity were assayed. 3. Control coronary flow was 73.1 +/- 19.9 ml min-1 100 g-1 and ansa subclavia nerve stimulation increased flow to 93.2 +/- 26.1. Baseline adenylyl cyclase activity averaged 51.9 +/- 38.8 pmol min-1 mg protein-1, while forskolin-stimulated activity was 588.2 +/- 393.6. Method variability was approximately 10% of the mean, much less than the biological variability of 70%. 4. Regression analysis of control flow vs baseline adenylyl cyclase activity produced the equation: flow = 0.25 (Adenylyl Cyclase)+60.6, (r = 0.47, P < 0.0001). The equation for stimulated flow vs stimulated adenylyl cyclase was: flow = 0.03 (Adenylyl Cyclase)+73.1, (r = 0.51, P < 0.0001). 5. Thus, significant heterogeneity of tissue adenylyl cyclase activity existed in the heart. There was also a direct linear relationship between adenylyl cyclase activity and coronary flow heterogeneity in canine left ventricle.

Adenylyl Cyclases↗
PubMed1993

Guinea pig maximization test of the bark extract from pawpaw, Asimina triloba (Annonaceae).

Several acetogenins, characteristic of the Annonaceae, have been found to exhibit pesticidal and feeding-deterrent activities against a variety of pests and are undergoing commercial development as pesticides. The sensitizing potential of one of these plants, pawpaw, Asimina triloba Dunal, was examined in the current study. The potential of Fraction F020 (a pesticidal crude extract of pawpaw stem bark) to sensitize and elicit an allergic contact dermatitis response was determined by using a modified guinea pig maximization test (GPMT). Fraction F020 is a weak sensitizer and the active compound, asimicin, a trihydroxy-bistetrahydrofuran fatty acid gamma-lactone, is a weak irritant.

Animals↗
PubMed1993

Levels of tumor necrosis factor alpha/cachectin (TNF alpha) in sera from patients with sickle cell disease.

Serum levels of tumor necrosis factor alpha/cachectin (TNF alpha) were studied in a group of adult patients with sickle cell disease (SCD), which include 31 patients with homozygous SS hemoglobinopathy and 10 patients bearing double heterozygous SC hemoglobinopathy and in their matched normal controls. All patients tested did not show any form of crisis for at least 4 weeks prior to the extraction of the sample. The amount of TNF alpha in serum was quantitated by means of an immunoenzymatic assay with a lower limit of detection of 25 pg/ml. The percentage of sera with detectable levels of TNF alpha was significantly increased in SCD patients as compared with the normal controls. Mean TNF alpha values in individuals with detectable levels of the cytokine were also significantly higher in the whole group of SCD patients and in patients bearing either SS or SC hemoglobinopathies than in the control group. An inverse correlation was observed between the percentages of Hb F and the levels of TNF alpha found in the sera from the patients.

Adult↗
PubMed1993

Clinical trials of primary care treatments for major depression: issues in design, recruitment and treatment.

The objective of this article is to consider whether randomized clinical trials (RCTs) are able to determine the validity of transferring treatments for major depression from the psychiatric to the primary care sector. This clinical issue is of growing concern in the United States since both governmental and professional bodies are establishing guidelines for the treatment of medical patients with the affective disorder. The article's method involves analysis of how the competing aims of rigorous scientific methodology (internal validity) and generalization of study findings (external validity) are best balanced within the RCT. Experiences in recruiting medical patients with major depression and providing pharmacologic, psychotherapeutic, and usual care interventions compatible with the sociotechnical characteristics of ambulatory medical centers are described to illustrate the complexities of investigating transferability of treatments for major depression with RCT methodology.

Antidepressive Agents↗
PubMed1993

The RBRVS for psychiatry.

Explore the source record for details and available documents.

Centers for Medicare and Medicaid Services, U.S.↗
PubMed1993

Interphase cytogenetics of gastric and esophageal adenocarcinomas.

Numerical changes affecting chromosomes 1, 2, 3, 4, 6, 7, 8, 10, 11, 12, 16, 17, 18, and the X and Y chromosomes have been analyzed using chromosome-specific centromeric alpha-satellite repeat DNA probes in a panel of biopsies of six gastric and three esophageal adenocarcinoma and one epidermoid carcinoma of esophagus obtained at surgery. For each case, with each probe, the number of hybridization signals were determined in 200 nuclei. Hybridization of each probe to phytohemagglutinin-stimulated normal peripheral blood lymphocytes served as controls. Monosomy was defined by loss of one signal in 15% or more cells and trisomy or tetrasomy was defined by the presence of 3 or 4 signals in 7% or more cells, respectively. The Y chromosome was lost in 6 of 8 cases and monosomy 10 was seen in 5 of 10 cases. Trisomy for chromosomes 17, 8, 7, 12, 11, and 1 was seen in 4 of 10, 4 of 10, 4 of 10, 2 of 10, 2 of 8, and 2 of 10 cases, respectively, and tetrasomy for chromosome 7 was seen in 1 of 10 cases. These data show that the Y chromosome and chromosomes 10, 8, 7, 17, and 12 are most frequently involved in nondisjunctional changes in these tumors. They also document the feasibility and utility of interphase cytogenetics of gastric adenocarcinomas.

Adenocarcinoma↗