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F Ramírez

Publications and source records attributed to F Ramírez.

30 records · Page 2Linked to original sources
PubMed1978

HLA--D typing with homozygous cells identified in an American indigenous isolate. I. Population studies.

Lymphocytes from six individuals homozygous for their HLA--A, --B, --C and --D loci belonging to an American indigenous group, the Warao, have been used as typing cells to detect HLA--D determinants in 121 donors from the same indigenous isolate and in 71 donors of mixed ethnic origin living in Venezuela. Two determinants responsible for strong proliferation in mixed lymphocyte cultures have thus been identified. Four HLA--A2, B5 cells (r values between 0l72 and 0.57) identify a determinant provisionally called LD5a showing a gene frequency of 0.30 among the Warao and of 0.09 among the population of mixed ethnic origin. The nearest B locus antigen to this new specificity among the Warao is HLA--B5 (r value = 0.20). A second determinant identified by two HLA--A2, B15 sisters (r values of 0.71) shows a gene frequency of 0.15 among the Warao and of 0.03 among the mixed population. The latter is related to Dw8 as shown by results of the VI and VII Histocompatibility Workshops, and is weakly associated (r value of 0.28) to HLA--B15 among the American indigenous population tested.

Epitopes↗
PubMedDate not supplied

[Diagnosis of venous thrombosis by using radioisotopes].

Thromboembolism problem is a grave complication which occurs with great frequency in patients hospitalized in a critical state. The association between periferical venous thrombosis and the thromboembolic accident is plainly demonstrated, although the accurate establishment of the clinical diagnosis of phlebothrombosis is only feasible in 50% of the cases. In the present work, we describe the methodology and the experience which we have acquired with the use of radioisotops in the diagnosis of these problems. We studied 64 patients to whom in the supine position we injected into a vein in both heels, from 3 to 5 millicuries of 99m-Tecnecio, practicing three stages: dynamic venography, a static study, and a pulmonary gammagram. In the normal cases, we clearly identified the tracts of the principal femural, iliac, and the inferior third of the inferior vena cava veins. In the abnormal studies, we observed the obstructive process manifested by the absence of radioactivity in the affected venous tract, with appearence of collateral circulation, definitive data which establishes with certainty the diagnosis. It can be concluded that the method is rapid and easily carried out, meaning that it could be a routine practice in all of those patients who are suspected of having this problem.

Adult↗
PubMedDate not supplied

[Clinical findings in active cerebral neurocysticercosis in pediatrics].

OBJECTIVE: We describe our experience in the study of active cerebral cysticercosis in paediatrics over a period of 6 years, involving a total of 85 cases, which were studied from the clinical, immunological and radiological points of view. The aim of this communication is to present the clinical characteristics of the disorder and its course when symptomatic treatment is given. DEVELOPMENT: The commonest age of presentation was school age. However, we had a large number of children under 4 years old. This shows that there is considerable endemicity in a group in which the disorder is considered to be less frequent. There were slightly more females than males, which is in accordance with another Mexican series. The predominant socio-economic level was poor (59%). The patients come from urban areas more and more frequently. The commonest signs were: convulsive crises, intracranial hypertension and headache without intracranial hypertension. The commonest type of crisis was partial, in its different forms. CONCLUSIONS: The course was mild and satisfactory in 90% of the patients. The good clinical progress was independent of the use of antiparasitic treatment.

Adolescent↗
PubMedDate not supplied

[Sclerotherapy with 75% ethanol in the control of hemorrhage caused by peptic ulcer disease].

We present our experience using ethanol as sclerosant of non-variceal bleeding lesions of the upper digestive tract and the result of its hemostatic effect when compared with patients who received conventional medical treatment. Since January 1989, 48 patients admitted with active bleeding or signs of high risk for rebleeding (clot or visible vessel) were submitted to sclerosis. The historic control group included patients admitted before 1989, being both groups comparable in clinical and endoscopic characteristics. Surgery was performed in 5 cases of the sclerosis group (10.4%) versus 14 of the control group (37.8%). Five of the patients in the sclerotherapy group died, one of them due to upper G.I. bleeding as the primary cause. We dit not observe a statistically significant difference in hospital stay, transfusion requirements or mortality. There were no complications as a result of the method. Sclerotherapy was not immediately effective in 2 patients; three patients who rebled were subject to new sclerosis, which was effective in controlling bleeding in two of them. In conclusion, sclerosis is a safe and effective method to achieve hemostasis, diminishing the re-bleeding and the need for surgery in cases of digestive bleeding due to peptic ulcer disease. Future studies using larger samples could show decrease in mortality.

Adolescent↗
PubMedDate not supplied

[Clinical and prognostic factors of mortality in upper digestive hemorrhage].

In order to investigate prognostic factors we prospectively followed 741 patients with upper gastrointestinal bleeding (UGIB). Eleven variables were identified with mortality predictive value. Hematemesis, age of 50 y/o, more than 120 heart beat/minute, 3 or more units of pack red blood cells, esophageal varices, cirrhotic liver and renal failure had independent predictive value. Our findings could help to identify high risk patients.

Age Factors↗
PubMedDate not supplied

[Upper gastrointestinal hemorrhage. Prospective analysis of 741 cases].

A prospective study was performed to evaluate the epidemiological characteristics and clinical outcome of patients with upper digestive bleeding. Between April 1987 and May 1993, 741 patients, 517 men and 224 women, with a mean age of 50.48 years (range, 12 to 94) were admitted to the emergency department with this diagnosis. The chief complaint was tarry stool (88.4%). A total of 717 patients underwent endoscopic examination within a mean time of 17.2 hours of arrival at the emergency department. Duodenal ulcers were found in 216 (35.9%) patients, gastric ulcer in 240 (32.4%), gastritis in 74 (10%), esophageal varices in 38 (5.1%), and other causes in 121 patients (16.5%). 478 required blood transfusion (range of 1 to 15 blood units transfused). 80.4% of patients who died necessitated transfusion versus 62.5% of the patients who had a satisfactory outcome. A total of 672 cases (92%) were managed with medical therapy. In 90 cases (12.2%) endoscopic injection treatment with 75% alcohol was performed. 60 patients (8.18%) had surgical therapy, 81.7% of whom underwent emergency operation to arrest bleeding. The global mortality was 10.6% (78 of 741 patients), compared to 18.3% in patients who were operated. The highest mortality occurred in patients with esophageal varices. We conclude that peptic ulcer is still the mayor cause of upper digestive bleeding. The high mortality found in patients who required surgical therapy creates the need to select those patients who may get benefits of alternate therapies which may improve the outcome.

Adolescent↗
PubMedDate not supplied

[Predictors of rehospitalization in schizophrenia].

OBJECTIVES: The aim of this study is to determine the predictive value on rehospitalization of sociodemographic variables, positive/negative symptoms and thought disorders. The results are part of research project founded by the Basque Health Department. METHODS: A 18 month follow-up study of a cohort of 60 patients with acute exacerbation of schizophrenia was carried out. The assessment was performed with DSM III-R diagnostic criteria, PANSS and CGI rating scales, and SCID-P semistructured interview. All patients received antipsychotic treatment. The sociodemographic and disease data, the dimensional score of the PANSS subscales, the score of CGI scale, the items 2, 12, 13 and 14 of the PANSS as indicators of formal thought disorders; and the items 1, 5, 6, 17 and 23 of the PANSS as content thought disorders were established as predictors. The predictive value was determined by the Cox regression test (Lee 1992). RESULTS: We did not find predictive value either in the PANSS scores or in the 9 thought disorders evaluated (Wald and RR tests were not significative). Nevertheless, considering the values of standard error obtained in the Cox regression we were not in a position to assure that they did not have an incidence in the hospitalizations. The CGI was the only scale that showed prognostic value (Wald test = 1.9945; RR = 1.7499). Our results indicated that the lower number of previous hospitalizations (Wald test = 1.1437; RR = 1.1437) and the high level of studies (Wald test = 2.4258; RR = 1.8052) diminished the risk of rehospitalization. CONCLUSIONS: 1 o The predictive value on rehospitalization for the positive/negative symptoms and thought disorders was not confirmed. 2 o CGI is the only scale with predictive value. That fact makes us consider the importance of what German psychiatrists called "smelling the schizophrenia" or "The smell of schizophrenia". 3 o Our results indicate that the lower number of previous hospitalizations, and the high level of studies diminish the risk of rehospitalization.

Adolescent↗
PubMedDate not supplied

[Positive and negative symptoms in schizophrenia: standards of change during acute exacerbation].

INTRODUCTION AND OBJECTIVES: The temporal stability of the positive and negative symptoms in schizophrenia deserves a special interest due to its consequences in the outcome and the treatment of the disease. This study determines the temporal stability of positive/negative subtypes in schizophrenia during the acute phase. MATERIAL AND METHODS: This is a clinical, observational and prospective study of a dynamic cohort of patients with acute exacerbation of schizophrenia defined by DSM III-R criteria. Patients with severe and unstable organic pathology, substance dependence, mental organic disorder, mental retardation, depression, or medicamentous parkinsonism were excluded. Clinical assessment was performed with the PANSS scale. Schizophrenic subtypes were established according to inclusive and restrictive criteria of PANSS. All patients were treated with new antipsycotics and biperiden if necessary. RESULTS: 51 patients were assessed for 8 weeks. In the baseline, the negative subtype (63.3% and 52.5% by inclusive and restrictive system respectively) and paranoid form (45.1%) were predominant. Three types of analysis were performed to determine the temporal stability: 1. Concordance (Kappa index). The concordance of the inclusive and restrictive System, regarding to the baseline assessment, indicated that both criteria had a low temporal stability. 2. Mc Nemar Ji Square. This test showed that these changes were bi-directional except for the first visit, which was significant through the restrictive system (higher change from the negative to other subtypes). 3. Transition analysis among groups by First Order Morkov Chains analysis indicated that this change was stationary (the change was the same in all phases). CONCLUSIONS: 1o The variable "time" has to be considered for the definition of subtypes in schizophrenia. 2o The restrictive system is more specific. It allows to identify a subgroup of patients with "Negative" schizophrenia with a high specificity and validity in clinical and epidemiological studies. 3o The use of the baseline visit as a reference (gold standard) is recommended because it exits a higher concordance among criteria and a more florid psychopathology.

Acute Disease↗