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E Prats

Publications and source records attributed to E Prats.

At least 55 records · Page 3Linked to original sources
PubMed1998

[A Spanish multicenter scintigraphic study of the breast using Tc 99m MIBI. Report of results].

UNLABELLED: The aim of this work has been to study, with a homogenous method, a wide sample of patients with breast cancer suspicion, in order to evaluate the real clinical usefulness of the scintimammography with MIBI-99mTc. METHODS AND MATERIAL: We have studied by way of prone scintimammography 388 patients (418 lesions) with breast cancer suspicion. In the mammography the size and degree of breast cancer suspicion was evaluated. Diagnosis was established by biopsy. RESULTS: 247 lesions were diagnosed as breast cancer and 171 as benign diseases. She results of the scintimammography were sensitivity 90%, specificity 70%, PPV 81% and NPV 83%. In palpable lesions sensitivity and specificity were 94% and 61%, and in non-palpable lesions 75% and 81% respectively. In 264 lesions mammographic breast cancer suspicion was establish. 13 of the 14 FN results were obtained in lesions with a high malignancy suspicion. In lesions with a low or indeterminate suspicion, sensitivity and NPV of the scintimammography were 97% and 98%. CONCLUSIONS: Scintimammography has a high sensitivity but a relatively low specificity in the study of lesions with breast cancer suspicion. Scintimammography could be a good complement of the mammography in lesions with a low or indeterminate suspicion of malignancy.

Adult↗
PubMed1998

[Scintigraphic assessment of the severity of inflammatory bowel disease using Tc 99m exametazime-labeled leukocytes].

The aim of the work was to value the utility of semiquantitative scintigraphics indexes (GI) as predictive factor of activity grade of intestinal inflammatory process in patients with confirmed diagnosis of inflammatory bowel disease (IBD). 64 patients have been studied (39 males and 25 females), mean age was 40,2 years (range: 18-88 years) with diagnosis of IBD in acute exacerbation confirmed by endoscopy and biopsy. In all patients was obtained abdominal scintigraphy with 99mTc-exametazine labelled leukocytes. The severity of intestinal inflammatory process was quantified using clinical indexes -Truelove-Witts index (TI) for ulcerative colitis (UC) and Crohn's disease activity index (CDAI), Harvey index (HI) for Crohn disease (CD)-, endoscopic index (EI) and haematological parameters: erythrocyte sedimentation rate (ESR), hematocrit, haemoglobin, leukocyte and platelet count, fibrinogen and albumin level. In all the scans regions of interest were drawn over liver, spleen, bone, abdominal background and positive intestinal segments. Subsequently three GI were calculated: GI1, GI2 and GI3 for the scans obtained at 30 min (P) and 3 h p.i. (T). The evaluation of UC severity showed significant correlation between: 1) The GI1 P and T and TI, EI, ESR, leukocyte and platelet count; 2) The GI2 P and TI and EI; 3) The IG2 T and EI, hematocrit and platelet count; 4) The GI3 P and TI, EI, ESR and platelet count; 5) The GI3 T and TI, EI, leukocytes and platelet count. In the evaluation of CD was observed significant correlation between the GI1 P and GI3 P with the CDAI and EI, between the GI1 T and the GI3 T with the CDAI and ESR; the GI2 did not show significant correlation with any of the valorised parameters. In conclusion, the scintigraphic activity indexes based in the semiquantitative evaluation of scans obtained with 99mTc-exametazine labelled leukocytes showed usefulness in the evaluation of the IBD severity, especially in the UC. Among the studied indexes, IG1 seems the more accurate.

Adolescent↗
PubMed1997

Lipoprotein alterations in liver cirrhosis: a possible contribution to changes in plasma oncotic pressure and viscosity.

BACKGROUND/AIMS: To investigate whether physicochemical alterations in plasma lipoproteins are associated with changes in plasma oncotic pressure and viscosity in liver cirrhosis. METHODS: The study included 66 patients with cirrhosis (confirmed by liver biopsy) and 58 healthy volunteers. The constituents measured were: the concentration, density and composition of plasma lipoproteins; plasma oncotic pressure and viscosity; and the concentrations of albumin, total protein, haptoglobin, transferrin, immunoglobulin M and alpha2-macroglobulin. RESULTS: Step-wise multiple regression analysis indicated that, in the patients with cirrhosis, plasma oncotic pressure was significantly correlated with plasma albumin+viscosity (r=+0.85; p<0.001) and with plasma total protein+the density of low density lipoprotein (r=+0.74; p<0.001). The inclusion of viscosity and the density of low density lipoprotein in the regression equations significantly improved the observed correlation between albumin and plasma oncotic pressure (r=+0.70; p<0.001). Similarly, plasma viscosity was significantly correlated with the sum of plasma total protein and cholesterol (r=+0.68; p<0.001). The inclusion of cholesterol in the regression equation significantly increased the observed correlation between total protein and plasma viscosity (r=+0.59; p<0.001). CONCLUSIONS: These results suggest that lipoprotein alterations associated with liver cirrhosis may play a role in determining plasma oncotic pressure and viscosity, and thus could influence the progression of the disease.

Adult↗
PubMed1997

Characterization and expression of the mouse endonuclease G gene.

Endonuclease G (Endo G) is a nuclease of prokaryotic lineage found in the mitochondria of vertebrates that has been suggested to play a role in mitochondrial DNA (mtDNA) replication. We have isolated and sequenced the entire mouse endo G gene, determined the limits of the mRNA, and mapped the promoter region. The coding sequence of the single copy gene is interrupted by two introns and analysis of the transcripts does not support a model by which more than one Endo G isoform could be produced by alternative splicing. We have also characterized a full-length human Endo G cDNA and comparison at the protein level of the human, bovine, and murine nucleases indicates a high degree of conservation except in the respective mitochondrial targeting signals. Endo G is ubiquitously expressed and the steady-state levels of its mRNA vary by a factor greater than seven between different tissues. The relationship between the mtDNA copy number and Endo G mRNA levels is not strictly proportional but tissues richer in mtDNA have higher amounts of the mRNA and vice versa.

Alternative Splicing↗
PubMed1997

Lack of founding Amerindian mitochondrial DNA lineages in extinct aborigines from Tierra del Fuego-Patagonia.

Ancient DNA from bones and teeth of 60 individuals from four extinct human populations from Tierra del Fuego-Patagonia (Selknam, Yamana, Kaweskar and Aonikenk) has been extracted and the mitochondrial DNA (mtDNA) amplified by using the polymerase chain reaction. High-resolution analysis of endonuclease restriction site variation in the mtDNA and sequencing of its hypervariable non-coding control region, revealed complete absence of two of the four primary mitochondrial haplotype groups present in contemporary Amerinds, namely A and B. In contrast, haplogroups C and D were found in all but one sample with frequencies of approximately 38% and 60%. These results, together with the decreasing incidence of group A in more southerly latitudes in the American continent and the absence of cluster B above 55 degrees North in America and Asia, argue that the first settlers entering America 21000-14000 years ago already lacked both mtDNA lineages.

Argentina↗
PubMed1997

The diagnostic value of Tc-99m human polyclonal immunoglobulin imaging compared to Tc-99m HMPAO labeled leukocytes in inflammatory bowel disease.

The aim of this study was to establish the usefulness of Tc-99m human polyclonal immunoglobulin (HIG) imaging in a group of patients who were suspected of having inflammatory bowel disease (IBD). The authors performed 30 scans (15 with Tc-99m HMPAO leukocytes and 15 with Tc-99m HIG) on 15 patients with IBD. Ten patients had Crohn's disease and five had ulcerative colitis. The sensitivity of Tc-99m HIG scintigraphy for detecting IBD was 33%, while the sensitivity of Tc-99m HMPAO leukocyte imaging was 100%. The Tc-99m HMPAO leukocyte imaging also detected a larger number of affected segments and provided better image quality of the extent of disease than Tc-99m HIG. On the basis of these results, the authors believe that Tc-99m HIG imaging is not a useful technique in the evaluation of patients with IBD, in the identification of location, or the extension or degree of disease activity.

Colitis, Ulcerative↗
PubMed1996

Community-acquired pneumonia in chronic obstructive pulmonary disease: a Spanish multicenter study.

Community-acquired pneumonia (CAP) is an infectious illness that frequently motivates hospital admission when comorbid conditions are present. However, the epidemiology of CAP in relation to the underlying disease of the patients is not well known. We performed a prospective multicenter study with the aim of assessing the clinical characteristics, etiology, and outcome of chronic obstructive pulmonary disease (COPD) patients with CAP. Between October 1992 and December 1994 we studied 124 COPD patients (mean FEV1 40 +/- 11% of predicted, mean FVC/FEV1 49 +/- 10) admitted because of CAP to one of the participating centers. An attempt to obtain an etiologic diagnosis was performed by means of blood cultures (n = 123), sputum cultures (n = 97), pleural fluid cultures (n = 17), protected specimen brush samples (n = 41), percutaneous transthoracic needle aspiration (n = 41), and serology (n = 106). Etiologic diagnosis was achieved in 80 (64%) of cases, however, diagnosis based upon valid techniques was only possible in 73 (59%) cases. The main causal microorganisms were the following: Streptococcus pneumoniae in 32 (43%), Chlamydia pneumoniae in 9 (12%), Hemophilus influenzae in 7 (9%), Legionella pneumophila in 7 (9%), Streptococcus viridans in 3 (4%), Coxiella burnetii in 3 (4%), Mycoplasma pneumoniae in 2 (3%), Nocordia asteroides 2, Aspergillus ssp. 1, and others 10. In three of these cases the etiology was polymicrobial. Bacteremia was present in 19 (15%) cases; S. pneumoniae was the most frequent isolate (13 cases). Antibiotic treatment was modified in 22 cases due to etiologic findings, and in 9 due to therapeutic failure. Ten patients died (8%), and 22 needed mechanical ventilation, the mortality rate in the latter population being 23%. Total or partial resistance of S. pneumoniae to penicillin was observed in 10 of 32 (31%) isolations, and to erythromycin in 2 (6%). The results of this study are important for the standardization of empiric antibiotic strategies in COPD patients with pneumonia.

Aged↗
PubMed1996

[The use of SPECT with 201Tl in the evaluation of brain tumors].

There is increasing interest in the literature regarding the use of SPECT (single photon emission computed tomography) with 201Tl in the evaluation of cerebral tumours. Thallium (201Tl) is one of the isotopes most commonly used in studies of the myocardium and in the diagnosis of various tumours. Normal brain takes up very little 201Tl, but in viable tumour tissue the 201Tl becomes intracellular and is rapidly cleared from the blood stream. Such cerebral tumour uptake is related to changes in the permeability of the blood-brain barrier, regional blood flow and transport by means of the Na(+)-K+ adenosine triphosphate pump. Once the SPECT images have been obtained following administration of the radioisotope, one can calculate the indices of early and of late uptake together with the retention index. The usefulness of SPECT in the preoperative detection of malignant expansive pathology, choice of tumour region during stereotaxic biopsy, control of tumour reproduction and their differentiation from post-radiotherapy necrotic tissue, and evaluation of chemotherapy in treatment of cerebral tumours are analyzed. Finally the application of SPECT in metastatic conditions and the differential diagnosis of expansive lesions is considered.

Blood-Brain Barrier↗
PubMed1996

Antineutrophil cytoplasmic antibodies in relatives of patients with inflammatory bowel disease.

BACKGROUND: The occurrence of antineutrophil cytoplasmic antibodies (ANCA) has been reported more frequently than expected in healthy first-degree relatives of patients with ulcerative colitis, suggesting that these antibodies may represent a subclinical marker of genetic disease susceptibility. AIM: To determine the prevalence of ANCA in unaffected first-degree relatives of inflammatory bowel disease patients in a Spanish population. METHODS: Three hundred and seventy sera obtained from 80 patients with inflammatory bowel disease (55 ulcerative colitis, 25 Crohn's disease), 217 unaffected first-degree relatives (157 from ulcerative colitis and 60 from Crohn's disease patients), 62 healthy controls, and 11 celiac disease patients were tested using an indirect immunofluorescence assay. RESULTS: Antibodies were detected in 64% of patients with ulcerative colitis but in only 12.5% of patients with Crohn's disease. ANCA were seldom present in their unaffected first-degree relatives (4.6%), control subjects (1.6%), and celiac disease patients (0%). CONCLUSIONS: In the Spanish population studied, antineutrophil cytoplasmic antibodies occur more commonly in ulcerative colitis than in Crohn's disease, as reported in other Caucasian populations. Moreover, their presence is not increased in their first-degree relatives. These findings indicate that ANCA are not a subclinical marker of genetic susceptibility to inflammatory bowel disease in this population.

Adult↗
PubMed1995

Efficacy, safety, and therapeutic relevance of transthoracic aspiration with ultrathin needle in nonventilated nosocomial pneumonia.

In order to determine the potential indications of transthoracic needle aspiration (TNA) using the ultrathin 25G needle for the diagnosis of nonopportunistic lung infections, we prospectively analyzed the diagnostic efficacy, safety, and therapeutic implications of its results in 97 patients with nonventilated nosocomial pneumonias (NVNP). The sensitivity of TNA was 60.9%. Specificity and positive predictive value (PPV) were 100%. Negative predictive value (NPV) was 34.1%. The complications in the studied cases were nil in 89 cases (91.8%), transient hemoptoic expectoration (< 10 ml) in five (5.2%), and self-limited partial pneumothorax in three (3.1%). No complications needing treatment were observed. On the basis of a positive TNA result, the initial antibiotic treatment was modified in 29 of 97 (29.9%) cases. In twelve of these, the empirical antibiotic regimen was demonstrated to be ineffective. We conclude that, using the 25G needle, TNA has a good diagnostic efficacy and is a safe procedure for the etiologic investigation of NVNP. A positive TNA result has significant therapeutic relevance, even in cases where broad-spectrum antibiotics are empirically prescribed.

Adolescent↗
PubMed1995

Structure of histone H2B and H4 genes of the sea cucumber Holothuria tubulosa.

A genomic library of the sea cucumber Holothuria tubulosa was screened with human and murine histone gene hybridization probes. A recombinant phage carrying an H4 gene was isolated and sequenced. Hybridization analysis of the entire 20 kb phage insert with probes for H1, H2A, H2B and H3 histones was negative except for H2B. This solitary arrangement of the two neighbouring histone H4 and H2B genes is in contrast to the organization of 'cleavage stage' histone genes, which are arranged in tandem quintets of genes encoding the 5 histone classes. Gene organization and sequence features indicate that the two Holothuria genes are the equivalents of a known pair of late H2B and H4 genes which have been described in the genome of sea urchins. This result shows that the simultaneous occurrence of tandem repeats of histone gene quintets and smaller groups of structurally distinct histone gene subtypes is not unique for sea urchins, but also applies to other echinodermata, such as the sea cucumber Holothuria tubulosa.

Amino Acid Sequence↗
PubMed1995

Risk factors for the development of Haemophilus influenzae pneumonia in hospitalized adults.

Potential risk factors for developing Haemophilus influenzae nosocomial pneumonia have not been sufficiently studied. We wanted to investigate the incidence and risk factors for the development of Haemophilus influenzae pneumonia in the hospital by means of a multivariate analysis. A total of 468 cases of nosocomial pneumonia were observed during the study period, 317 (68%) of which were aetiologically diagnosed by means of highly reliable methods, and H. influenzae was isolated in 57 of them. Fifty of the 57 episodes of H. influenzae pneumonia occurred in mechanically-ventilated patients. Underlying diseases were: medical in 12 cases, surgical in 15 cases, and traumatological in 22. Variables associated with Haemophilus influenzae nosocomial pneumonia in intubated patients after the univariate analysis were: "period between admission and pneumonia 2-7 days" and "no previous antibiotics". A multivariate analysis demonstrated that the variables "no previous antibiotics" and "coma on admission" were risk factors for H. influenzae pneumonia. In nonintubated patients, no risk factors were found for H. influenzae pneumonia compared with other nosocomial pneumonia. We conclude that H. influenzae was involved in 57 out of 317 (18%) of nosocomial pneumonia registered in our institution, and the majority of patients (50 out of 57) were mechanically-ventilated. In this particular subgroup, coma of the patient on admission to hospital and absence of antibiotic treatment prior to developing pneumonia constitute two definite risk factors for developing H. influenzae nosocomial pneumonia.

Adult↗
PubMed1994

Plasma lipoprotein alterations in patients with chronic hepatocellular liver disease resulting from alcohol abuse: effects of alcohol intake cessation.

Cholesterol and triglyceride in plasma and lipoprotein fractions and serum apoprotein concentrations were measured in 51 chronic alcoholic subjects; 23 had minimal or mild hepatic changes (steatosis and/or fibrosis) and 28 had cirrhosis. Of the latter, 16 had stopped alcohol consumption at least 3 months before the study, while the other 12 and all the mildly affected patients had continued drinking. None of the patients presented with cholestasis or alcoholic hepatitis. The control group was composed of 15 healthy, non-drinking volunteers selected from the hospital staff with an age- and sex-distribution similar to that of the alcoholic group. Patients with minimal hepatic changes had plasma total cholesterol concentrations within the ranges of the normal population but with increased high density lipoprotein and decreased low density lipoprotein fractions. Total plasma triglyceride values were not significantly elevated but the distributions in the low density lipoprotein and high density lipoprotein fractions were significantly increased in patients compared to controls. This alteration was accompanied by a consistent increase in serum apolipoprotein C-III concentration. Conversely, in patients with cirrhosis, serum concentrations of apolipoproteins A-I and B were significantly lower and were reflected in the cholesterol concentrations in the lipoprotein fractions. Comparisons between abstainers and non-abstainers within the group with cirrhosis indicated that cessation of alcohol intake was not sufficient to rectify lipoprotein dysfunction following damage from cirrhosis.

Adult↗