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A Macedo

Publications and source records attributed to A Macedo.

At least 55 records · Page 3Linked to original sources
PubMed1995

Immunological detection of blast cell subpopulations in acute myeloblastic leukemia at diagnosis: implications for minimal residual disease studies.

The aim of the present study was to analyze the incidence of AML cases displaying more than one blast cell subpopulation by immunophenotype at diagnosis, since, any of them, although minimal, can be responsible for the relapse. For this purpose we have prospectively investigated the immunophenotype of blast cells from 40 de novo AML patients at diagnosis with a large panel of monoclonal antibodies in double and triple staining combinations analyzed at flow cytometry. The discrimination between the different cell populations was based on: (1) the existence of aberrant phenotypes; (2) differences in light-scatter characteristics; and (3) the expression of differentiation-associated antigens (CD34, CD117, HLADR, CD33, CD15, CD14, CD11b and CD4). More than one blast cell subpopulation was identified in 34 patients (85%), two subpopulations in 12 patients (30%), three in three cases (7.7%), four in 13 patients (32.5%) and five populations in six cases (15%). The most common criteria for discrimination of blast cell subpopulations was based on the expression of maturation-associated antigens and, interestingly, the blast subpopulations defined by higher reactivity for myeloid differentiation-associated markers had a more mature FSC/SSC pattern. In 53% of the patients at least one of the subpopulations identified was minimal (< 10% of the total leukemic cells). Regarding the existence of aberrant phenotypes three situations were observed: (1) none of the subpopulations had antigenic aberrations (10 cases); (2) coexistence of normal and aberrant subpopulations (five cases); and (3) all the subpopulations displayed aberrant phenotypes (19 cases). In 17 of the 23 patients (74%) who had two or more blast cell subpopulations with phenotypic aberrations, at least one aberrant criteria was common to all the subpopulations; this criteria by itself would permit the simultaneous identification of all subpopulations in minimal residual disease (MRD) studies. In the remaining cases the investigation of MRD should be based on the phenotypic characteristics of each subpopulation.

Antigens, CD↗
PubMed1993

Expression of NK and lymphoid-associated antigens in blast cells of acute myeloblastic leukemia.

In the present study, the expression of two NK-associated antigens (CD56 and CD16) together with six 'classically' considered lymphoid-related markers (TDT,CD19,CD10,CD7,CD2,CD4) has been analyzed by appropriate dual combinations in 265 acute myelogenous leukemia (AML) patients. Among the lymphoid markers, CD4 and CD7 were those most frequently expressed by AML blast cells (58% and 21.6%, respectively) while the incidence of positivity for the other markers was lower: CD19 (7.8%), CD10 (10.9%), CD2 (11.4%), and TDT (11.3%). Regarding NK-associated antigens, CD56 was present in 41% of AML cases analyzed whereas CD16 was detected in only 23%. All but one of the CD16+ cases coexpressed the CD56 antigen. The expression of these antigens was not associated with the degree of cell differentiation assessed either by morphological or immunophenotypical criteria, with the exception of the correlation observed between monocytic leukaemias and the expression of the CD4, CD56, and CD16 antigens. Regarding the prognostic value of the markers investigated, CD56 expression was associated with a tendency for a better outcome whereas CD7 was the only antigen that had an adverse influence on the survival of AML patients.

Antigens, CD↗
PubMed1992

[Left cor triatriatum. Clinical and echocardiographic polymorphism].

Four cases of cor triatriatum in children aged from 4 days to 12 months are described. In one case isolated classical form of the disease occurred, and in the other it was associated respectively to ventricular septal defect, anomalous pulmonary venous connexion and persistence of left superior venae cava. One child had successful surgical correction, two died before surgery could be attempted and one waits operation. Relevant clinical and investigational data are described and the role of echocardiography as an excellent diagnostic tool is stressed. We conclude that isolated form of cor triatriatum can simulate primary lung disease and when associated to other cardiac anomalies it has an earlier diagnosis due to early referral. Surgical results and prognosis depend not only on associated anomalies but also on early diagnosis.

Abnormalities, Multiple↗
PubMed1992

[Heart surgery without previous heart catheterization, in pediatric cardiology].

STUDY OBJECTIVE: To determine the influence of echocardiography in the preoperative diagnosis of heart diseases in children. DESIGN: Retrospective study. SETTING: Hospitalized children admitted in Departments of Pediatric Cardiology and Cardiothoracic Surgery. PATIENTS: Children of both sexes, aged from neonate to 14 years old, with heart disease who underwent cardiac surgery. MATERIAL AND METHODS: From January 1989 to July 1990, 220 consecutive cardiac surgeries were performed in children with heart disease. The initial diagnosis was based on data from clinical examination, electrocardiogram, thorax X-Ray and echocardiogram (M-mode, 2D, conventional and colour Doppler). Patients were separated in three groups according to their ages: newborn infants less than 28 days old; infants less than 12 months old; children more than 1 year old and less than 14 years old. Patients were separated according to the investigations used further for preoperative diagnosis: whether they had or not cardiac catheterization performed prior to surgery. RESULTS: From 220 surgical interventions performed, 124 were "open heart" surgeries (9 neonates, 28 infants and 87 children) and the remaining had "closed heart" operations (14 neonates, 37 infants and 45 children). Preoperative diagnosis was mainly dependent on echocardiography, dispensing catheterization in 90 cardiac interventions. The diagnosis was confirmed at surgery or at autopsy. There were 9 deaths, 3 of which occurred in patients not submitted to cardiac catheterization. CONCLUSIONS: Echocardiography is a reliable method for investigation and establishment of the preoperative diagnosis of heart diseases in children. Its use may further reduce the need for diagnostic catheterization in children, particularly in risk groups.

Adolescent↗
PubMed1990

Regulation of the hexaheme nitrite/nitric oxide reductase of Desulfovibrio desulfuricans, Wolinella succinogenes and Escherichia coli. A mass spectrometric study.

Dissimilatory nitrite reduction, carried out by hexaheme proteins, gives ammonia as the final product. Representatives of this enzyme group from 3 bacterial species can also reduce NO to either ammonia or N2O. The redox regulation of the nitrite/nitric oxide activities is discussed in the context of the denitrifying pathway.

Ascorbic Acid↗
PubMed1990

[Changes in the coronary arteries in Kawasaki disease: echocardiographic aspects].

OBJECTIVE: Evaluation of coronary anomalies in children with Kawasaki disease (KD) by two-dimensional echocardiography. SETTING: Outpatient and Laboratory of Echocardiography in the Pediatric Cardiology Department of Santa Marta Hospital. PATIENTS: Forty four children (M/F = 1.7/1) with a mean age of 2 years and 8 months (range from 2 months to 8 years) underwent Outpatient and serial echocardiographic study from July 1984 to December 1988. RESULTS: Coronary artery anomalies were demonstrated in 13 (52%) of 44 children; 11 (25%) had uniform dilatation and 12 (27%) had aneurysms. These anomalies were never observed before the first week of illness. During a mean follow-up of 8.4 months, we have observed normalization of coronary arteries lumen, in 10 (43.4%) of the 23 cases. The anomalies remained in 13 (56.6%). CONCLUSIONS: Coronary artery anomalies are a frequent complication of KD. In about 50% of patients, coronary artery anomalies remained in a mean follow-up of 8 months. Two-dimensional echocardiography is a good method to study coronary anomalies in KD.

Child↗
PubMed1990

[Usefulness of the immunologic phenotype in the diagnosis of chronic lymphoproliferative syndromes with splenomegaly as the dominant clinical manifestation].

From a total number of 221 patients with leukaemic lymphoproliferative syndromes studied at the Hospital dos Capuchos, in Lisbon, seven patients whose cell morphology differed from that of "classical" lymphoproliferative syndromes were separated; marked splenomegaly without lymph node enlargement was present in all of them. Immunophenotypic studies confirmed B-cell origin of the lymphoproliferation in the seven patients. Small lymphocytes with mature appearance predominated in three of these cases, presenting as: a) the only cell population (with immunophenotype RR+, FMC7-, CD5+), b) along with a significant amount of prolymphocytes (RR+, CD5+, FMC7+), c) accompanying a population of cells with lymphoplasmacytoid differentiation (RR-, CD5-, CD38+, associated to serum monoclonal IgM). Those data strongly suggested that these three lymphoproliferative syndromes corresponded, respectively, to a classic B-cell chronic lymphocytic leukaemia, a chronic lymphocytic leukaemia with prolymphocytes, and an immunocytoma. In three other cases the morphology of the proliferating cells was intermediate between prolymphocytes and hairy cells (i.e., variant hairy cells) and they strongly reacted with monoclonal antibodies FMC7 and LeuM5 (CD11c), showing low positivity with antigens CD5 and CD25, in the absence of receptors for mouse red blood cells. The remaining B-cell lymphoproliferative syndrome studied had small centrocytes in peripheral blood, their phenotype being RR-, CD5+, FMC7+/-, CD10+ and CD38+, which suggested a centrofollicular lymphoma with leukaemic expression. In summary, the present study seems to confirm the heterogeneity of the chronic lymphoproliferative syndromes showing splenomegaly as an outstanding clinical feature. Immunophenotype along with cell morphology are important in the differential diagnosis, especially whenever splenectomy cannot be carried out, in order to choose the appropriate therapy.

Antigens, Differentiation↗
PubMed1988

Comparison of the metabolic control of diabetes achieved by whole pancreas transplantation and pancreatic islet transplantation in rats.

To compare the long-term effectiveness of whole pancreas transplantation and pancreatic islet transplantation in controlling the metabolic disorders of alloxan diabetes, metabolic studies were performed monthly for 2 years in 4 groups of highly inbred rats: (1) NC-116 nondiabetic controls; (2) DC-273 untreated alloxan-diabetic controls; (3) PDT-182 rats that received syngeneic pancreaticoduodenal transplants shortly after induction of diabetes with alloxan; and (4) IT-92 rats that received an intraportal injection of at least 1500, but usually 2000, syngeneic pancreatic islets shortly after induction of diabetes with alloxan. Whole pancreas transplantation maintained strict metabolic control throughout the 2 years of study. In group PDT, hyperglycemia was abolished; plasma glucose concentration was maintained tightly within the normal range; markedly depressed plasma insulin levels were raised to above normal; glucose tolerance tests had insulin levels above normal and glucose levels that increased less and declined more rapidly than normal; and body weight gain and growth approached normal. In contrast, pancreatic islet transplantation failed to maintain precise metabolic control. In group IT, plasma glucose concentration initially fell to normal but then was elevated significantly above normal beginning with the 3rd posttransplant month; plasma insulin level declined progressively after the 6th posttransplant month; glucose tolerance tests had a diabetic glucose tolerance curve as a result of a markedly deficient plasma insulin response; and body weight gain and growth were significantly less than in group PDT. The results of these long-term metabolic studies may explain the effectiveness of whole pancreas transplantation and the ineffectiveness of pancreatic islet transplantation in preventing diabetic nephropathy.

Animals↗
PubMed1988

Effect of pancreas transplantation on diabetic somatic neuropathy.

To determine whether pancreas transplantation is capable of preventing diabetic somatic neuropathy, metabolic studies and electron microscopic morphometry of the sciatic nerve were performed monthly for 2 years in four groups of highly inbred rats: (1) NC-28 nondiabetic controls; (2) DC-82 untreated alloxan-diabetic controls; (3) WPT-122 diabetic rats that received a syngeneic whole-pancreas transplant; and (4) IT-90 diabetic rats that received intraportal injections of 1500 to 2000 syngeneic pancreatic islets. Five diabetic nerve lesions were quantitated by a "blind" protocol: intra-axonal glycogen deposits, axons with glycogen deposits, demyelinated axons, intact axoglial junctions in paranodal terminal myelin loops, and basal lamina thickness of vasa nervorum. Untreated diabetic control animals had significant and progressive increases in all five nerve lesions compared to nondiabetic controls (p less than 0.01). Whole pancreas transplants produced precise metabolic control of diabetes and prevented development and progression of all five diabetic nerve lesions throughout the 2-year study period. Pancreatic islet transplantation produced strict metabolic control and prevented diabetic neuropathy for the first 6 months, but then diabetes recurred and nerve lesions that were similar in severity to those in untreated diabetic rats developed. The finding that whole pancreas transplantation prevents diabetic somatic neuropathy adds to and extends our previous studies showing that whole-pancreas transplants prevent diabetic nephropathy.

Animals↗
PubMed1987

Comparison of whole pancreas and pancreatic islet transplantation in controlling nephropathy and metabolic disorders of diabetes.

To compare the long-term effectiveness of whole pancreas transplantation and pancreatic islet transplantation in controlling the metabolic disorders and preventing the kidney lesions of alloxan diabetes, metabolic and morphologic studies were performed in four groups of rats: (1) NC-116 nondiabetic controls; (2) DC-273 untreated alloxan-diabetic controls; (3) PDT-182 rats that received syngeneic pancreaticoduodenal transplants not long after induction of diabetes with alloxan; and (4) IT-92 rats that received an intraportal injection of at least 1500 and usually 2000 syngeneic pancreatic islets soon after induction of diabetes with alloxan. Each month for 24 months after diabetes was well established, body weight and plasma concentrations of glucose and insulin were measured, and five lesions were scored by light microscopy in 50 glomeruli and related tubules in each kidney by a "blind" protocol: glomerular basement membrane thickening, mesangial enlargement, Bowman's capsule thickening, Armanni-Ebstein lesions of the tubules, and tubular protein casts. There were progressive and highly significant increases in the incidence and severity of all five kidney lesions in the diabetic control rats compared with the nondiabetic control rats. No significant differences were found between the kidneys of Group PDT and those of Group NC, demonstrating that whole pancreas transplantation prevented all of the diabetic kidney lesions throughout the 2-year study period. In contrast, within 3-9 months after pancreatic islet transplantation and thereafter, the incidence and severity of the five diabetic kidney lesions were similar in Group IT and Group DC. Whole pancreas transplantation produced precise metabolic control of diabetes throughout the 24 months of study, whereas pancreatic islet transplantation did not accomplish complete metabolic control, particularly beyond the first several months after transplantation. The difference in the completeness of metabolic control achieved by the two types of transplants is the most likely explanation for their sharp difference in effectiveness in preventing diabetic nephropathy.

Animals↗
PubMedDate not supplied

Biological parameters and molecular markers of clone CL Brener--the reference organism of the Trypanosoma cruzi genome project.

Clone CL Brener is the reference organism used in the Trypanosoma cruzi Genome Project. Some biological parameters of CL Brener were determined: (a) the doubling time of epimastigote forms cultured in liver infusion-tryptose (LIT) medium at 28 degrees C is 58 +/- 13 hr; (b) differentiation of epimastigotes to metacyclic trypomastigotes is obtained by incubation in LIT-20% Grace's medium; (c) trypomastigotes infect mammalian cultured cells and perform the complete intracellular cycle at 33 and 37 degrees C; (d) blood forms are highly infective to mice; (e) blood forms are susceptible to nifurtimox and benznidazole. The molecular typing of CL Brener has been determined: (a) isoenzymatic profiles are characteristic of zymodeme ZB; (b) PCR amplification of a 24S alpha ribosomal RNA sequence indicates it belongs to T. cruzi lineage 1; (c) schizodeme, randomly amplified polymorphic DNA (RAPD) and DNA fingerprinting analyses were performed.

Animals↗
PubMedDate not supplied

[Structural changes in pulmonary vessels and coronary arteries in hypoplastic left heart syndrome].

In order to correlate gross morphological features with pulmonary and coronary vasculature changes in hypoplastic left heart syndrome (HLHS) 15 heart-lung necropsy specimens from neonates were analysed. Histology of left atrium wall, lung vessels with pulmonary arteriolar disease morphometric grading, study of intra and extra pulmonary wall veins and coronary arteries were recorded. Classic HLHS was observed in 11, and DORV with mitral atresia in 4, the foramen ovale (FO) being the only left atrium outflow tract in all. All specimens had increased % of thickness and muscular extension of arterioles and increased wall thickness of pulmonary veins, but severer arteriolar and venous changes with left atrium fibrosis were noticed in 8 specimens with either closed FO (3 cases) or mean FO diameter (d) of 5 mm when compared with specimens with mean FOd of 9 mm. Coronary arteries histology disclosed in 4 of 8 specimens with opened but hypoplastic mitral valve, intima proliferative changes with lumen narrowing, not observed in 7 specimens with mitral valve atresia. We concluded that in HLHS closed or restrictive FO and permeable mitral valve may predispose neonates to respiratory complications, right ventricle abnormal function and arrhythmias, specially after cardiac surgery.

Aorta↗
PubMedDate not supplied

[Endocarditis caused by Candida parapsilosis after total correction of tetralogy of Fallot. Medico-surgical treatment].

Three children with Candida Parapsilosis endocarditis after total surgical correction for Tetralogy of Fallot, are reported. Blood cultures became negative in one child with amphotericin-B and in the other two with Ketoconazole, before reoperation for septal patch replacement. Oral therapy with Ketoconazole continued for a total of 24 months, and during a mean follow-up of 36 months no side effects or reinfection occurred. Medical and surgical conjoined therapy, with surgical timing decided on clinical and laboratorial grounds, were important for good results and cure.

Candidiasis↗
PubMedDate not supplied

[Interatrial communication associated with dilated cardiomyopathy].

A case of atrial septal defect in association with dilated cardiomyopathy is presented. Evolutive features are mainly assessed by echocardiography. On initial presentation the findings on physical examination pointed to the diagnosis of atrial septal defect with severe congestive heart failure. In addition to the demonstration of the congenital heart disease, echocardiography showed very dilated right atrial and ventricular cavities and later appearance of right atrium intracavitary thrombi. Left cavities were initially normal but, after surgical repair of the atrial septal defect, they rapidly increased. Endomyocardial biopsy confirmed the diagnosis of cardiomyopathy, which clinically seemed to only affect the right ventricle, but actually shown to be a diffuse myocardial disease.

Cardiomegaly↗