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J Monteiro

Publications and source records attributed to J Monteiro.

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

Oligoclonality in the human CD8+ T cell repertoire in normal subjects and monozygotic twins: implications for studies of infectious and autoimmune diseases.

BACKGROUND: We have previously demonstrated CD8+ T cell clonal dominance using a PCR assay for the CDR3 length of T cell receptors belonging to a limited number of TCRBV segments/families. In this study, we have modified this approach in order to analyze more comprehensively the frequency of oligoclonality in the CD8+ T cell subset in 25 known TCRBV segments/families. In order to assess the relative roles of genes and environment in the shaping of a clonally restricted CD8+ T cell repertoire, we have analyzed clonal dominance in the CD8+ T cell population of monozygotic twins, related siblings, and adoptees. MATERIALS AND METHODS: Oligoclonality was assessed in the CD8+ T cell subsets using a multiplex PCR approach to assay for CDR3 length variation across 25 different TCRBV segments/families. Specific criteria for oligoclonality were established, and confirmed by direct sequence analysis of the PCR products. This assay was used to investigate the CD8+ T cell repertoire of 56 normal subjects, as well as six sets of monozygotic (MZ) twins. RESULTS: Seventy-two percent of normal subjects (n = 56) had evidence of oligoclonality in the CD8+ T cell subset, using well-defined criteria. Although MZ twins frequently displayed CD8+ T cell clonal dominance, the overall pattern of oligoclonality was very diverse within each twin pair. However, we occasionally observed dominant CD8+ T cell clones that were highly similar in sequence in both members of some twin pairs. Not a single example of such similarity was observed in normal controls or siblings. CONCLUSIONS: Oligoclonality of circulating CD8+ T cells is a characteristic feature of the human immune system; both host genetic factors and environment shape the pattern of oligoclonality in this T cell subset. The high frequency of this phenomenon in normal subjects provides a background with which to evaluate CD8+ T cell oligoclonality in the setting of infection or autoimmune disease. Further phenotypic and functional characterization of these clonally expanded T cells should provide insight into normal immune homeostasis.

Adolescent↗
PubMed1992

Decreased expression of Fc gamma RIII mRNA in leukemic granulocytes.

Morphologically mature granulocytes from patients with chronic myeloid leukemia show significant impairment in their ability to internalize aggregated IgG, a ligand that is rapidly phagocytosed by normal human granulocytes. With a view to understand the molecular basis of this defect, normal and leukemic granulocytes were examined for the steady-state levels of mRNA for Fc gamma RIII, a membrane-associated receptor that initially binds and traps the IgG-opsonized antigens. Northern blot analyses revealed that the level of the specific mRNA in CML granulocytes was between 0.08 and 0.69 times that seen in the normal granulocytes. This could be one of the contributory factors for the observed endocytic defect in the leukemic granulocytes.

Blotting, Northern↗
PubMed1992

[Formation of left ventricular thrombus in acute myocardial infarction: significance of the determination of fibrinogen, of products of fibrinogen degradation, and of plasminogen].

OBJECTIVE: To evaluate the significance of the fibrinogen, the plasminogen and the fibrinogen degradation products levels as marks of left intraventricular thrombosis (LIVT) in acute myocardial infarction (AMI). METHODS: 219 consecutive patients of AMI admitted in a Coronary Care Unit of an University Hospital, were prospectively studied. All protocols included a clinical evaluation, an M-mode and 2D echocardiographic study and blood samples, at day 1, 3, 7 and at hospital discharge. In the intraventricular thrombus evaluation just the 4 Asinger grade was considered. In the laboratory evaluation we used: the Clauss chronometric method for the fibrinogen, the colorimetric method for the plasminogen and the agglutination in plaque for the FDP. The patients with ECO in the 2 or 3 Asinger grades and those in which ECO and laboratory study were not performed in the same day, were excluded. 101 patients remained on the study, and they were divided in two groups: 53 patients with LIVT and 48 patients without it. RESULTS: In both groups the fibrinogen raised along the first six days of the AMI, however in the group with LIVT this level didn't raise as high as in the group without LIVT (p < 0.001). In the FDP evaluation two peaks were found, one at 48 hours and another on the 6 th day, but there were no differences between the two groups. The plasminogen values raised along the first week of AMI, in a similar way in both groups. CONCLUSIONS: a) Fibrinogen levels raises in AMI, but this elevation is significantly smaller in the group with LIVT, which suggests fibrinogen consume in fibrin formation of the thrombus. b) FDP and plasminogen levels raise along the first week of AMI, but in a similar way in the two groups. c) None of these parameters permitted to individualize patients with thrombus formation.

Aged↗
PubMed1992

[Coronary atherosclerosis in acute myocardial infarct. Anatomic profile of diverse causes of death].

OBJECTIVE: to study the degree of coronary obstruction by atherosclerotic plaques in a population dying with acute myocardial infarction. We defined subgroups by the degree of the obstructive lesion and compared the severity and distribution of coronary atherosclerotic lesions in different groups according to cause. STUDY DESIGN: systematic prospective study in patients dying in the acute phase of myocardial infarction in a University Hospital Coronary Unit during a four years period. POPULATION AND METHODS: we studied 193 patients corresponding 77% of the patients dead in the same period. 24 patients were excluded by technical reasons related to the preparation of necropsic material. The clinical protocol included 64 parameters and were considered the following causes of death: left ventricular failure (shock or acute pulmonary edema), left ventricular free wall rupture, interventricular septum rupture, primary asystole, pulmonary embolism and ventricular fibrillation. To study of the heart we performed the transverse slices technic after fixation; to study the epicardial coronary arteries we isolated the coronaries after fixation and made 5 mm transverse slices. The slices were macroscopic and microscopic evaluated for the degree of coronary obstruction in every 5 mm segment. We classified the degree of coronary obstruction in five grades: less than or equal to 25%; greater than 25% e less than or equal to 50%; greater than 50% e less than or equal to 75%; greater than 75% e less than 100%; and total obstruction. RESULTS: the degree of coronary obstruction in each epicardial segment were: Right ostium--grade I = 21%, grade II = 46%, grade III = 26%, grade IV = 7%, grade V = 0; Right coronary--grade I = 5%, grade II = 10%, grade III = 19%, grade IV = 28%, grade V = 38%; Left ostium--grade I = 27%, grade II = 50%, grade III = 19%, grade IV = 4%, grade V = 0; Left main--grade I = 16%, grade II = 43%, grade III = 28%, grade IV = 10%, grade V = 2%; Anterior descendent--grade I = 1%, grade II = 5%, grade III = 11%, grade IV = 34%, grade V = 49%; Left circumflex--grade I = 2%, grade II = 14%, grade III = 22%, grade IV = 40%, grade V = 22%. The number of coronary arteries with more than 75% obstruction for each group of one, two or three vessel disease were: 1 vessel--41 cases; 2 vessels--56 cases; 3 vessels--68 cases. The number of vessels with more than 75% obstruction for each cause of death were: Wall rupture--1 vessel = 20, 2 vessels = 18, 3 vessels = 11; Septum rupture--1 vessel = 0, 2 vessels = 2, 3 vessels = 2; Shock--1 vessel = 12, 2 vessels = 21, 3 vessels = 30; Acute pulmonary edema--1 vessel = 1, 2 vessels = 9, 3 vessels = 7; Asystole--1 vessel = 4, 2 vessels = 1, 3 vessels = 8; Pulmonary embolism--1 vessel = 2, 2 vessels = 5, 3 vessels = 8; Ventricular fibrillation--1 vessel = 2, 2 vessels = 0, 3 vessels = 2. CONCLUSION: in most patients dying with acute myocardial infarction, the coronary atherosclerotic lesions were present in two or three epicardial coronary arteries. The left anterior descendent artery was the more frequent artery with major lesion (greater than 75%). Major atherosclerotic lesion in just one vessel were more frequent in patients dying by cardiac rupture.

Autopsy↗
PubMed1990

[The importance of heart disease in the various types of cerebral vascular disease. A prospective study].

UNLABELLED: A prospective study was performed in 106 patients with acute stroke. The main purpose was the cardiac evaluation in the different types of cerebrovascular disease: Intracerebral hemorrhage (H), Cortical ischaemic events (C) and Subcortical ischaemic events (SC) and also to evaluate the interest of echocardiography in detecting occult cardiac sources of emboli. The study population included 54 men and 52 women with a mean age of 66.8 +/- 10.3 years. A thorough neurologic and cardiologic study with a computed tomography of the brain (TAC) and an echocardiogram (ECO) were performed in all patients. It was found 24 (23%) of H, 40 (38%) of C and 32 (30%) of SC. In the past history, heart diseases were more prevalent in C (p less than 0.04); previous stroke and systemic hypertension (HTA) were less prevalent in H (p less than 0.008) and in C (p less than 0.004), respectively. Atrial fibrillation (FA) was more frequent in ischaemic stroke (p less than 0.02) and within these in C (p less than 0.005). No more clinical and functional cardiac features or echocardiographic aspects had any difference in their prevalence in different types of stroke. Without clinical heart disease there were 19 (18%) cases but only in 10 were found in their echocardiograms a potentially embolic heart disease (PEHD) but 8 of them had questionable pathologic significance. IN CONCLUSION: C had more heart disease in their past history; FA is more frequent in C; it is difficult to diagnose a cerebral embolism with only a coexistent C and CPE, but if there is FA or a past history of heart disease in a C, the diagnosis of cerebral embolism is more probable; finally, echocardiography is of limited value to diagnose a PEHD in the elderly, however it makes possible to better evaluate most cardiac situations.

Acute Disease↗
PubMed1989

[Clinical methods for evaluating infarct size and its anatomic correlations. A study conducted with 193 cases. II. Evaluation of infarct size by determining maximal creatine phosphokinase in serum. Enzimatico-anatomic correlations].

AIMS: To compare the infarct size calculated by the peak serum CK method with the anatomic infarct size in a population dying of acute myocardial infarction. CONCEPT AND PLACE OF THE STUDY: To use the method of peak serum CK in the assessment of infarct size, calculated by a method developed by the authors, in a population dying of acute myocardial infarction in a coronary care unit. METHODS: 193 patients who successively died with acute myocardial infarction entered the study. After establishing the exclusion criteria the anatomical infarct size was measured using the method developed by the authors of myocardial slices after fixation of the heart and by the peak CK method. The two methods were correlated using linear regression curves. RESULTS AND CONCLUSIONS: A global correlation between the two methods was found although wide scattered values were found. After dividing the population in several subgroups, the analysis showed that survival below 48 hours, death in left ventricular failure, inferior infarcts and reinfarction influenced negatively this correlation. The anatomical method showed its value for this kind of evaluation having always in mind its known limitations. The enzyme method looked less discriminating as peak CK, obtained by 12 h sampling will seldom reflect the peaks of CK liberation curve. As the study was applied to a population of patients dying of acute myocardial infarction its results cannot be applied without caution to a population of survivors. We anticipate that in such a population peak CK will have a better correlation with real CK peaks even with 12 hours sampling and therefore reflecting more accurately infarct size.

Autopsy↗
PubMed1989

[Clinical methods for evaluating infarct size and its anatomic correlations. Study carried out in 193 cases. III. Comparison of data on the evaluation of the infarct size using the QRS score and a method of maximal creatine kinase determination in the serum].

AIMS: To compare two methods concerning the clinical evaluation of infarct size--one using a QRS score, the other based on peak Ck values--applied to the same population. CONCEPT AND PLACE OF THE STUDY: to determine--based on previously established correlations between a QRS score and the anatomic total infarct size on one hand, and between the peak CK values and the anatomic recent infarct size on the other hand--which myocardial infarction subgroup constitutes the best indication for each method. The study took place in a Coronary Care Unit of a Central Hospital. MATERIAL AND METHODS: 193 patients who died successively of acute myocardial infarction through out 4 years were studied. After establishing the exclusion critéria, the QRS score was calculated according to the method of Selvester modified by Wagner, and peak CK values were evaluated. Infarct size, either recent or old, was determined by means of an anatomical method developed by the authors and based on Hackel's and Alonso's previous works. Correlations were established between data from each clinical method and those from the anatomical method. Several myocardial infarction subgroups were considered for comparison of the correlations found in each subset. RESULTS AND CONCLUSIONS: As long as QRS score was regarded, significant correlations were found between the evaluation by QRS score and anatomical infarct size in the subgroups of patients with severe pump failure, prior myocardial infarction, or total loss of ventricular muscle mass of at least 20 percent; however, a significant correlation was missing when the whole myocardial infarction group was taken into consideration. When peak CK value were considered, a weak significant correlation was found between the evaluation by enzyme determination and anatomical infarct size in the whole group of patients, but a stronger correlation was present in the subgroups of patients with survival longer than 24 hours, anterior wall myocardial infarction, free wall cardiac rupture, or first acute myocardial infarction. In conclusion the choice of the method to be used in the clinical evaluation of infarct size should take into account the type of population beeing studied, and follow the results obtained in different myocardial infarction subgroups as mentioned above.

Creatine Kinase↗
PubMed1989

[Cerebral vascular disorders and arterial hypertension: cardiologic and neurologic aspects].

OBJECTIVE: To report and discuss some cardiologic, neurologic and radiologic aspects in different types of stroke (AVC) present in hypertensive patients. DESIGN: Retrospective study in patients with acute cerebrovascular accident (AVC) and high blood pressure (HTA). Separate this population in three groups according to the results of computerized tomography scanning of the brain (TAC): hemorrhage (H) cerebral infarction (IC) and lacune (L). In each group describe the findings. SETTING: Department of Internal Medicine in a University Hospital of Lisbon. PATIENTS: Thirty-four patients, after having discarded 8 because their TAC were normal. Twenty were men (M), 14 women (F) with a total age average of 58 years. MEASUREMENTS AND MAIN RESULTS: All patients had AVC, HTA and underwent initial TAC. For each group were considered: Past history, cardiac repercussions of HTA, neurologic features and the localisations of cerebral lesions. For statistical study were used the Student T Test. There was 45% of IC, 24% of H and 26% of L. In past history was found 35% of cardiac diseases and 24% of diabetes. There wasn't any difference in blood pressure (systolic and diastolic) between the groups. Fifty-six percent had an important cardiac repercussion, with 72% of alterations of ventricular repolarization and 35% of coronary heart diseases. Both were more prevalent in IC than in the others. Twenty percent of H were in physical activity, 20% had a progressive start and in 10% there were meningeal signals. The site of cerebral lesions were characteristical, specially the H and L and 60% of H were thalamic. There wasn't any lacune neither in the cerebral stem nor in the cerebellum. It was reviewed some theoric aspects of neurologic feature. CONCLUSIONS: IC is the more frequent AVC in hypertensive patients. The cardiac involvement, is the most frequent disease in past history. The cardiac repercussion of HTA is more important in IC. The findings were insufficient to well characterize the neurologic feature. Sometime TAC and seldom magnetic resonance are necessary. The localisations, specially of H and L are the same that have been described in medical literature.

Aged↗
PubMed1980

Human lymphocyte colony formation in agar culture: cell phenotype studies on individual colonies indicate a polyclonal origin of such colonies.

Monoclonal origin of human lymphocyte colonies grown in agar culture under mitogenic stimulation is still disputed. To solve this question we used different markers: we failed with the G6PD technic and with the successive staining for X and Y chromosomes on individual colonies. Therefore, individual colonies were investigated for the presence of different cell types using membrane receptor identification and cytochemistry. At different stages of the colony formation, presence of a macrophage surrounded by lymphocytes, of a mixture of T cells and B cells, plasma cells and c.Ig negative cells, in the same colony was demonstrated. The mixture of cells from different lineages in individual colonies indicated a polyclonal origin of such colonies, the capacity for the cells to migrate in a short distance, and the involvement of cell-cell contact throughout the colony formation. Human lymphocyte colony formation appears as a new technic for the study of cellular cooperation.

Adult↗
PubMed1978

Techniques to improve the seating of castings.

A convergence of 20 degrees for full crowns is the most likely to be seen clinically, as determined by random measurements taken at a dental laboratory. Castings did not seat without cement, by an average of 215 micron at 10 degrees of convergence, or by 99 micron at 20 degrees of convergence. Biting forces will seat a casting approximately 150 micron, but will cause random concentrations of force against tooth structure, thus compressing it. All castings tend to rebound from this position. Zinc phosphate and polycarboxylate cemented crowns seated to 33 micron and 20 micron respectively when relieved, but each were elevated to 112 micron when not relieved. A silicophosphate cement displaced crowns with 20 degrees of convergence 122 micron under "ideal" clinical conditions, even when relieved; and with CBA 9080 cement, more than 500 micron. A die relief method was found to be the most suitable of the three casting compensation techniques. Casting retention, after cementation, was increased by 25%.

Cementation↗
PubMedDate not supplied

Oligoclonality of CD8+ T cells in health and disease: aging, infection, or immune regulation?

Oligoclonality of the CD8+ T cell subset is a common and characteristic feature of the normal human peripheral T cell repertoire. These clonally expanded populations are predominantly found in a CD57+ or CD28- CD8+ T cell subset. While CD8 oligoclonality is somewhat more common in the older age group, it is also very prevalent in young to middle-aged adults. Recent experiments have also demonstrated that the clonally expanded populations may actually occur in two distinct subpopulations of CD8+ CD28- cells, distinguished by the expression of the CD57 surface marker. A major difficulty with studies involving CD8+ CD28- CD57+ T cells is their relative lack of proliferative capacity. We have recently investigated the possibility that this phenotype may be due to a state of "replicative senescence" in some cases. In this regard, we have demonstrated that the telomere lengths of CD8+ CD28- T cells are generally shorter than that of their CD8+ CD28+ counterparts, consistent with a distinct replicative history for the CD8+ CD28- population. Additional studies of the normal biology of clonally expanded CD8+ T cells are likely to yield important insights into immune function in health and disease.

Aging↗
PubMedDate not supplied

[The patient with acute cerebrovascular disorders: assessment of associated diseases].

We performed a prospective study in 106 patients with acute stroke. The main purpose was to evaluate the associated diseases and to determine their prevalence and incidence in two different types of cerebrovascular disease: the intracerebral hemorrhage (HI) and ischaemic events (AI). The studied population included 54 men and 52 women with a mean age of 66.8 +/- 10.3 years. A clinical examination was performed in all patients by different specialists and all were submitted to diverse complementary tests, including a computed tomography scan of the brain (TAC) and an echocardiogram (ECO). We found 24 (23%) HI and 82 (77%) AI. In the past history, previous stroke were more prevalent in AI (p less than 0.01). Heart disease was present in 87 (82%) patients but, among them, only atrial fibrillation which was found in 19 (18%) patients, was significantly more frequent in AI (p less than 0.02). Hypertension (HTA) existed in 79 (75%) patients, respiratory complications and periferic vascular disease in 9 (8%), diabetes in 44 (42%) and dyslipidemia in 31 (29%) patients. No significant difference was found between the two groups of stroke regarding these diseases; however, there was a tendency for HTA and diabetes to be more prevalent in HI and for periferic vascular disease in AI. In the blood tests, high haematocrit was found in 35 (33%) patients, anemia in 21 (20%), hypercholesterolemia in 17 (16%), hypertrigliceridemia in 18 (17%) and uremia or creatinemia or ionic alteration in 32 (30%) patients, without any difference in their prevalence and incidence in the two groups of stroke. In conclusion, in this prospective study of patients with an acute stroke, there was 23% of HI and 77% of AI, a high prevalence of previous stroke, heart disease and HTA, but only the previous stroke and, within heart disease, the atrial fibrillation were significantly more frequent in the AI group. Also, periferic vascular disease had a tendency to be more frequent in AI, as well as diabetes and HTA had in HI.

Acute Disease↗
PubMedDate not supplied

[Incidence and forms of clinical presentation of the various morphologic types of myocardial laceration in the acute phase of infarct. A 4 years' caseload at a coronary unit. A clinico-anatomic study of 193 successive cases].

AIMS: To determine the incidence of different morphological type of myocardial laceration (wall rupture) in patients who died of acute myocardial infarction, as well as to study the several clinical forms of presentation of different types of myocardial laceration. CONCEPT OF THE STUDY: To apply a protocol of prospective study, that includes 64 clinical and 34 anatomical parameters, using very discriminative technics in the anatomical study, already presented in previous papers. PLACE OF THE STUDY: The study took place in a CCU and pathological department of a University Hospital. POPULATION: Of 1308 patients successively admitted in a CCU with acute myocardial infarction between 1983-1986, 252 have died. It was possible to perform a necropsy study in 193. The only criterion for inclusion was the family agreement. METHODS: The study was a prospective one, being excluded only the patients in whom the anatomical study didn't confirm recent myocardial infarction. The clinical data were observed during the stay in the CCU, using a protocol developed for this study. In the anatomical study a protocol developed by the authors was applied, using very discriminative anatomical quantification technics of the infarct size as well as of the coronary obstruction degree by atherosclerotic plaques. In the study of the myocardial laceration a fourteen septal perpendicular cuts technic was applied, with a laceration development macroscopic study, and microscopic study of the more interesting cuts. All data were stored and treated in a computer program developed for this study. RESULTS: From the 193 cases that have been studied, 49 presented a complete free wall rupture (25%) and in two others there were an interventricular septal rupture and free wall rupture. The amount of free wall rupture was then 51 cases (26%), with a corrected incidence for the population with AMI of 5.1%. In 7 cases we found an interventricular septal rupture (in two cases associated with complete free wall rupture and in other two cases with an incomplete left ventricular rupture), what represents an incidence in necropsy of 3.6%. Since that in this period five patients with septal rupture have been operated and in three others the hemodynamic diagnosis was made, dying this patients without being performed necropsic study, the amount of septal ruptures was of 15 cases, what represents a corrected incidence of 1.1% in the population with AMI. The clinical forms of presentation of free wall rupture were the following: syncope followed by death (60%), shock (21%), transitory syncope (4%), psycho-motor troubling (4%). Pain persistence or recurrence associated with other clinical symptoms occurred in 63% of the patients. Hypotension, not always evoluting to shock, occurred in 33%, and pericarditis in 21% of the cases. When the different anatomical types of free wall rupture were considered (type I-direct rupture; type II-multicanalicular rupture; type III-rupture covered by an interventricular thrombus), we observed that in type I there was prevalence of syncope (71% and only 50% showed pain persistence or recurrence, when in type II syncope occurred in 67% and shock in 22%, with pain in 56%, and in type III the occurrence of syncope and shock were similar (44% vs 38%), with pain in 81% of the cases. Hypotension was verified in 56% in type III, 21% in type I and 22% in type II. Pericarditis never occurred in type I, happened in 33% in type II and 25% in type III. The terminal accident took an average 44 minutes long in type I, 3.8 hours in type II and 9.2 hours in type III. The delay in admission was nine hours in type I, 19 in type II and 30 in type III, and the time between the onset of symptoms and death was 2.9, 2.7 and 5.4 days respectively in types I, II and III. In what concerns the interventricular septal rupture shock occurred in all cases but one, in which association with free wall rupture determined cardiac tamponade with syncope.(ABSTRACT TRUNCATED AT 400 WORDS)

Aged↗
PubMedDate not supplied

[Pulmonary embolism in acute myocardial infarct. Clinico-anatomic study of 19 cases].

The aim of this study was to evaluate the incidence of pulmonary embolism as the cause of death in acute myocardial infarction; to define the anatomic and clinical profile of a subset of patients deceased by pulmonary embolism; to study the localization and characteristics of pulmonary emboli. An anatomic and clinical protocol was systematically applied to the dying patients with acute myocardial infarction admitted in a CCU of an University Hospital. Therefore, 193 patients consecutively deceased by acute myocardial infarction were studied. Sixty-four clinical parameters were evaluated together with 34 anatomic parameters concerning a very discriminative anatomic study protocol. The sole exclusion criterion for necrotic study was the lack of family consent; necropsy was thus performed in 77% of patients. Therefore, we verified that the incidence of pulmonary embolism as the cause of death was 9.8%. Delay in admission as well as the interval between the onset of symptoms and death, were longer in the deceased by pulmonary embolism than in subjects showing other causes of death. Bradycardia was absent in pulmonary embolism patients, and asystole was the terminal electric accident in the great majority of cases; heart weight was greater, and biventricular infarction and right ventricular thrombosis were also more frequent in this subset of patients. In almost half of cases, pulmonary emboli were located in the main pulmonary artery, being multiple and peripheral in four.

Aged↗