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F Arriaga

Publications and source records attributed to F Arriaga.

At least 19 recordsLinked to original sources
PubMed1992

[Research in psychogeriatrics. Various theoretical and methodologic aspects].

The rapid increase in individuals aged 65 years old and more in the general population has directed attention to geriatrics, a medical specialty concerned with the study, prevention and treatment of pathological conditions in the aged. Among these conditions, frequent psychiatric disturbances occur and therefore it is widely recognized the increasing role of psychogeriatrics. A comprehensive review of theoretical and methodological issues related with research in psychogeriatrics is presented. In a short introduction, the state of the art in some main areas is analyzed. It is pointed out that controversial and unsolved problems still influence the ongoing research in this field. The use of different theoretical models is discussed, taking into consideration their specific scope and drawbacks. Psychopathological phenomena in the elderly are under the influence of a variety of etiologic and pathogenic factors and the conclusion arises that an adequate conceptual framework can be provided by systemic and multifactorial models. However, in order to preserve their explicatory power, they require valid and reliable definitions of all variables involved--not only independent and dependent variables, but also mediating variables--as well as clear hypothesis on their relationships. Different approaches for the fulfillment of these requirements are discussed.

Ethics, Medical↗
PubMed1992

[The use of cryopreserved homografts in reconstructing the right ventricular outflow tract in congenital cardiopathies].

In recent years the use of cryopreserved allograft valves has become very popular. Homograft valves have been used for aortic valve replacement and for reconstruction of the outflow tract of the right ventricle for more than 30 years with very good results. Recently the method of cryopreservation has made possible the creation of valve banks. The use of this cryopreserved valves has obtained very good short and medium term results. We present our experience with the use of cryopreserved allograft valves in the reconstruction of the right ventricular outflow tract in the treatment of complex cardiac malformations. We have operated 15 children. Six were diagnosed of different types of transpositions of the great arteries with ventricular septal defect and pulmonary atresia or stenosis. There were 2 deaths not related to the use of the allograft valves. Nine other patients were diagnosed of different types of complex cardiac malformations. One patient with a univentricular heart and pulmonary stenosis and a neonate presenting with a truncus arteriosus communis died after the operation; again the deaths were not related to the use of the homograft conduits. Our technique of cryopreservation consists in the procurement of aortic and pulmonary valves from multiorgan donor patients. The valves are sterilized in antibiotics for 48 hours. Then the process of freezing is began with a period of progressive cooling down to -40 degrees C and second phase of storage in liquid nitrogen to a temperature of -178 degrees C. The short and medium term results are very satisfactory. We have not seen late important complications.

Adolescent↗
PubMed1991

[Harvesting of mononuclear cells from peripheral blood in malignant hemopathies].

After demonstrating through animal models that progenitor cells with haemopoietic regenerative capability are present in peripheral blood, such precursor cells were also found in the mononucleated cell (MNC) fraction of human peripheral blood. It was shown that such cells increase in the recuperative period following chemotherapy. A number of studies have demonstrated that autologous infusion of such MNC achieved by cytapheresis may lead to a quick restoration of haemopoiesis. The initial results of peripheral blood MNC achievement in 18 patients with different malignancies of the blood are presented in this paper. Ninety-one cytapheresis sessions were carried out, 88 with a Fenwall CS-3000 continuous-flow machine, and the remaining three with a Haemonetics V-50 discontinuous-flow cell separator. The number of sessions per patient ranged from three to six and the harvested MNC count was 19.3 x 10(9)/L, the percentage of recovery being 56.4%. Some studies are currently in course aimed to analyse the MNC subpopulations in order to measure the progenitor-cell fraction and to establish the viability of such cells for further transplants. Since only five patients have recently been transplanted, all successfully, no definite conclusions can be drawn presently in this connection.

Adolescent↗
PubMed1991

[Culture of cells forming granulomonocytic colonies in bone marrow (GM-CFU) in myelodysplastic syndromes and their relation to hematological findings and FAB subtype].

The results of "in vitro" culture of granulomonocytic precursor cells (CFU-GM) of the bone marrow from 44 patients were analysed in the present work. The correlation with the patient's haematological characteristics, their FAB subtypes (i.e., 6 cases of refractory anaemia (RA), 11 of acquired sideroblastic anaemia (ASA), 15 cases of refractory anaemia with excess blasts (RAEB), 5 cases of RAEB in transformation (RAEBT) and 7 cases of chronic myelomonocytic leukaemia (CMML), and the survival were examined as well. The technique used for cell culture was that of Pike and Robinson, following the classification proposed by Florensa for estimating the growth patterns. Anomalies of the myeloid clonal proliferation were found in 81% of the cases. There was direct correlation between the number of aggregates and the polymorphonuclear cell count, whereas the highest number of blast cells coincided with increased number of clusters in cultures. CNNL showed the highest aggregate counts. The B growth pattern (both colony and aggregate growth) was most frequently seen in CMML; pattern C2 (decreased colonies with increased aggregate count) appeared in RAEB, RAEBT and CMML, and pattern C3 (decrease of both colony and aggregate counts) was found only in RA and ASA. None of the culture findings appreciably associated with the survival.

Aged↗
PubMed1990

The sleep of dysthymic patients: a comparison with normal controls.

All-night electroencephalographic (EEG) sleep recordings were compared in dysthymic patients and normal controls. Patients were selected according to DSM-III and underwent 2 weeks of treatment with placebo before the sleep evaluation, which also included self-assessments of sleep quality. As compared with normals, dysthymic patients demonstrated fragmented and superficial sleep with no changes in rapid eye movement (REM) sleep. In addition to sleep continuity disturbances, dysthymics had a higher percentage of stage 1 and a reduction of slow wave sleep (SWS), mainly due to a diminished percentage of stage 4. Other differences were related to a higher incidence of some EEG events, and it is suggested that the analysis of sleep microstructure is a useful approach to study sleep physiology in psychiatric patients. The classification of minor forms of depression is a controversial issue and therefore the nosological implications of our findings are discussed.

Adult↗
PubMed1990

Absence of central effects with levocabastine eye drops.

Twelve healthy volunteers were randomly allocated to receiving in a double-blind cross-over fashion levocabastine eye drops (0.5 mg/ml solution) and placebo. They were advised to instill 2 drops per eye, four times daily. Each treatment was administered for a period of 1 week. Before and after each treatment period psychomotor function was assessed using Critical Flicker Fusion Test and the Choice Reaction Time Test. At the same time intervals a subjective evaluation of sedation was given using a Visual Analogue of Sedation. Both objective and subjective measurements showed that no significant treatment effects could be detected. It is concluded that repeated instillations of levocabastine eye drops are devoid of any sedative side effects.

Adult↗
PubMed1990

[Transfusion management of a patient with multiple anti-erythrocyte antibodies (anti-c + anti-K + anti-Fyb + anti-Jkb) subjected to a valvular reoperation using extracorporeal circulation].

A woman with multiple anti-red cell antibodies (anti-c, anti-K, anti-Jkb, anti-Fyb) due to previous transfusions was admitted to the hospital for valvular replacement. To ensure enough transfusional supply, a high number of packed red cell units was typed and screened prior to previous operation. Haemorrhagic complications developing during surgery led to transfusion of 32 blood units, 20 of them compatible. Besides this, measures directed to prevent complications derived from haemolytic disease were instituted. These included intravenous fluids and diuretics to maintain circulatory integrity and improve renal cortical blood flow. High-dose gammaglobulin was also administered in an attempt to decrease extravascular haemolysis. Despite therapy, severe adult distress respiratory syndrome caused patient's death nine days after surgery. We remark the need of storing frozen blood of low-frequency phenotypes in blood banks to face significant transfusional problems, providing sufficient numbers of antibody-compatible blood.

Agglutinins↗
PubMed1988

Effects of ritanserin on sleep disturbances of dysthymic patients.

Ritanserin, a selective and potent serotonin-2 antagonist, is effective in the treatment of a variety of syndromes related to anxiety and depression, including dysthymic disorder. In animals and healthy volunteers, ritanserin specifically increases slow-wave sleep and the hypothesis arises that this effect on sleep may contribute to its therapeutic properties. Therefore, we studied the effects of ritanserin on sleep in a group of dysthymic patients (DSM-III). Polygraphic recording as well as subjective evaluations of the quality of sleep were performed before and at the end of a 4-week period of double-blind medication with either ritanserin (10 mg o.d. in the morning) or placebo. At baseline, patients showed at fragmented and superficial sleep, with low amounts of slow wave sleep. Ritanserin significantly increased Slow Wave Sleep and changed the frequency and distribution of some stage transitions during the night. No other sleep parameters were modified by ritanserin treatment.

Adult↗
PubMed1988

Effects of lithium on dopamine behavioural supersensitivity induced by rapid eye movement sleep deprivation.

The effects of lithium on the potentiation of d-amphetamine-induced hyperlocomotion were evaluated in rapid eye movement (REM) sleep deprived rats. Under control conditions, pretreatment with lithium during 7 days did not modify the hyperlocomotion produced by d-amphetamine. REM sleep deprivation induced a pronounced potentiation of the locomotor response to d-amphetamine. In a stress control group this potentiation also occurred, but to a lesser degree than in the REM sleep deprived group. Lithium pretreatment prevented the increased response to d-amphetamine in both REM sleep deprived and stress control animals. The effects of lithium in REM sleep deprived rats are in accordance with reports that lithium is able to prevent the development of dopamine receptor supersensitivity. However, it cannot be excluded that in both REM sleep deprived and stress control groups the increased response to d-amphetamine is related to noradrenergic changes and/or noradrenergic-dopaminergic interactions. REM sleep deprivation seems to be an interesting model to study the underlying mechanisms of manic-depressive illness.

Animals↗
PubMed1987

Mimicking anti-S simulating a delayed transfusion reaction.

An autoantibody mimicking anti-S specificity is described in an S-s+ patient. The antibody was detected 2 weeks after transfusion. The direct antiglobulin test (DAT) was positive and the antibody was thought to be an alloantibody formed after the transfusion. Eighteen months later, the DAT was still positive and anti-S could be eluted from the patient's red blood cells in spite of the fact that these were S-s+. The autoantibody was characterized as mimicking anti-S specificity by in vitro absorption studies. It was present during the 3 years in which the patient was observed without causing hemolitic anemia.

Aged↗
PubMed1985

[Biologic reagents].

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