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Featured researches published by Luiz Alberto Magna.


Pathology Research and Practice | 1998

THE VALUE OF PCNA AND AGNOR STAINING IN ENDOSCOPIC BIOPSIES OF GASTRIC MUCOSA

Silvia Pierre Irazusta; José Vassallo; Luiz Alberto Magna; Konradin Metze; Miriam Aparecida da Silva Trevisan

The aim of the present study was to examine the usefulness of the quantification of PC10-positive-cells and of Argyrophilic Nucleolar Organizer Regions (AgNORs) in gastric biopsies for the identification of gastric mucosal proliferative lesions. Fifty seven paraffin-embedded endoscopic biopsies were classified into four histologic groups: normal, inflammatory, dysplastic and neoplastic mucosa. The percentage of PC10-positive cells was determined by immunohistochemistry. The AgNOR parameters determined included the total number of all identifiable silver precipitations in the nucleus, the mean number of silver precipitations per cluster, and the presence of morphologically heterogenous silver precipitations. Group comparisons were performed using the Kruskall Wallis and Dunn non-parametric tests with a significance level of 5%. A discriminant analysis (followed by the jack-knife procedure) was performed using the three AgNOR parameters plus the percentage of PCNA-positive cells as the independent variables and histological groups as the dependent variable. All three AgNOR parameters, as well as the percentage of PCNA-stained nuclei, showed their highest values in the carcinoma group. However, no good differentiation among the four histologic groups was obtained using only one of these parameters, since there was always considerable overlap among them. By combining all the parameters in a linear discriminant analysis, we obtained a correct classification in 48 out of 57 cases. Within the classification errors there was only one false positive carcinoma, which was in fact a dysplasia and only one false negative carcinoma erroneously classified as dysplasia. The number of cells with heterogenous AgNORs was the most important parameter for the discriminant analysis. No correlation between PCNA values and the AgNOR parameters could be found, thus indicating that they do not represent the same phenomenon in the cell cycle. We concluded that the use of a combination of various proliferation parameters in a linear discriminant analysis may be helpful for differentiating gastric mucosal lesions. The peculiar AgNOR morphology is an important variable which should be taken in consideration in quantitative studies. PCNA and AgNORs seem to represent different physiological phenomena in the cell cycle.


Journal of Behavior Therapy and Experimental Psychiatry | 2011

Assessment of obsessive beliefs: Comparing individuals with obsessive-compulsive disorder to a medical sample☆

Makilim Nunes Baptista; Luiz Alberto Magna; Dean McKay; José Alberto Del-Porto

Cognitive behavior models for Obsessive-Compulsive Disorder (OCD) are based currently on the presence of specific beliefs associated with the disorder. Among these beliefs are inflated responsibility, concerns over thought-action fusion, and overimportance of thoughts. The aim of this study was to compare scores from the subscales of the Obsessive Beliefs Questionnaire (OBQ-87), developed by the Obsessive-Compulsive Cognitions Working Group (OCCWG, 2001), in 24 patients from an OCD clinic (OCD) and 24 patients from a Medical Clinic (MC) for ambulatory and chronic diseases. All OCD patients were diagnosed using the SCID, and the OCD portion of the SCID was used to rule out patients with OCD from the MC group. The Yale-Brown Obsessive-Compulsive Scale (YBOCS) and Dysfunctional Attitudes Scale (DAS) were also administered. The results indicated that, contrary to predictions, in the domains of Tolerance for Uncertainty, Threat estimation, Responsibility and Perfectionism, the MC group presented higher scores than the OCD group. The same findings occurred with DAS, which was significantly correlated with the OBQ. Possible explanations for these findings are discussed, as well as suggestions for future research with both groups.


Jornal De Pediatria | 2011

Time of diagnosis of oral clefts: a multicenter study

Lívia G. Amstalden-Mendes; Ana Carolina Xavier; Denise K. Antunes; Ana Carolina R. G. Ferreira; Rita Tonocchi; Agnes Cristina Fett-Conte; Raquel N. Silva; Vera H. V. Leirião; Lázara P. C. Caramori; Luiz Alberto Magna; Vera Lúcia Gil-da-Silva-Lopes

OBJECTIVE To determine the time of diagnosis of typical orofacial clefts in different Brazilian regions and its influence on age at surgical correction. METHOD This was a prospective, descriptive, cross-sectional study conducted in medical centers in the Southeast, South, and Northeast of Brazil. Trained speech therapists and geneticists interviewed the parents of affected children using a previously validated questionnaire. Epi-Info and SPSS were used for data analysis. Significance level was set at 5% (p ≤ 0.05). RESULTS The sample consisted of 215 interviews conducted in the following regions: 21.9% (47) in the Southeast, 51.1% (110) in the South, and 27% (58) in the Northeast. Monthly family income was higher in the Southeast (p ≤ 0.05). Cleft lip and palate were found in 61.4% (132) of cases, cleft palate in 20.9% (45), and cleft lip in 17.7% (38). Diagnosis occurred in the maternity ward in 75.3% (162) of cases, during the prenatal period in 14% (30), and after hospital discharge in 10.2% (22). The Southeast had a higher frequency of prenatal diagnosis (27.7%), possibly related to greater purchasing power in this region and greater availability of prenatal investigation. Of all cases diagnosed in the maternity ward, 74.4% occurred in the Northeast. However, no significant difference was found when comparing time of diagnosis, region, and age at first surgery. CONCLUSION Considering that diagnosis is more common in the maternity ward, local health care teams should be trained in order to effectively improve the initial care of these patients. Although time of diagnosis did not affect age at surgery, it favors the planning of neonatal care and treatment of affected infants.


Transplant Immunology | 2009

Prospective analysis between the therapy of immunosuppressive medication and allogeneic microchimerism after liver transplantation

Margareth Batistella Araujo; Luiz Sergio Leonardi; M.I. Leonardi; I.F.S.F. Boin; Luiz Alberto Magna; Eduardo A. Donadi; M.H.S. Kraemer

After liver transplantation, migration of donor-derived hematopoietic cells to recipient can be detected in peripheral blood. This state is termed microchimerism. The aim of this study was to investigate prospectively the presence of allogeneic microchimerism, the occurrence of acute cellular rejection and the level of immunosuppression in transplanted patients. Microchimerism occurrence between 10 days and 12 months after liver transplantation was analyzed in 47 patients aged between 15 and 65 by a two-stage nested PCR/SSP technique to detect donor MHC HLA-DR gene specifically. A pre-transplant blood sample was collected from each patient to serve as individual negative control. Microchimerism was demonstrated in 32 (68%) of the 47 patients; of these, only 10 patients (31.2%) presented rejection. Early microchimerism was observed in 25 patients (78.12%) and late microchimerism in 7 patients (21.8%). Among the patients with microchimerism, 14 were given CyA and 18 were given FK506. In the group without microchimerism, 12 patients were given CyA and 03 were given FK506. There was a significant association between the presence of microchimerism and the absence of rejection (p=0.02) and also between microchimerism and the type of immunosuppression used. Our data indicate that microchimerism and probably differentiation of donor-derived leukocytes can have relevant immunologic effects both in terms of sensitization of recipient and in terms of immunomodulation toward tolerance induction.


Revista Brasileira De Otorrinolaringologia | 2007

Marginal mandibulectomy in the surgical treatment of tonsil and retromolar trigone tumours

Maria Beatriz Nogueira Pascoal; José Francisco de Sales Chagas; Nivaldo Alonso; José Luiz Braga de Aquino; Marcus Castro Ferreira; Maria Isabel Nogueira Pascoal; Luiz Alberto Magna

UNLABELLED Resection of the ascending ramus of the mandible can result in considerable functional and esthetic damage. AIM To compare the survival rate and local and regional recurrence in marginal and segmental mandibulectomy for advanced tonsil and retromolar trigone tumours with no mandibular invasion. PLACE AND PERIOD: Reference Head & Neck Service, between October 1994 and December 2001. MATERIAL AND METHOD 20 stage IV patients undergoing marginal mandibulectomy and 22 undergoing segmental mandibulectomy were compared. CASE STUDY a contemporary cross-sectional cohort study. RESULTS Of 20 patients undergoing marginal mandibulectomy, 35% died of the disease, 15% due to local recurrence, 15% due to regional recurrence and 5% due to local and regional recurrence. Of 22 patients undergoing segmentary mandibulectomy, 36,4% died of the disease, 31,8% due to local recurrence and 13,6% due to distant recurrence. The Kaplan-Meier analysis showed a 55% survival rate for the marginal mandibulectomy group, and a 45% survival rate for the segmental group (p= 0.8329). CONCLUSIONS Analysis of the two groups showed that conservation of the ascending ramus of the mandible, even in advanced lesions with no mandibular involvement, does not increase the recurrence rate.


The Cleft Palate-Craniofacial Journal | 2013

Feeding Infants With Cleft Lip and/or Palate in Brazil: Suggestions to Improve Health Policy and Research

Vera Lúcia Gil-da-Silva-Lopes; Ana Carolina Xavier; Denise Klein-Antunes; Ana Carolina R. G. Ferreira; Rita Tonocchi; Agnes Cristina Fett-Conte; Raquel N. Silva; Vera H. V. Leirião; Lázara P. C. Caramori; Luiz Alberto Magna; Lívia G. Amstalden-Mendes

Objective To verify feeding resources used prior to corrective surgery among cleft babies from Brazil and to discuss suggestions to improve common feeding problems around the world. Design Cross-sectional descriptive study conducted at eight medical centers. Participants A total of 215 parents or guardians of cleft children. Methods Interview based upon a prevalidated questionnaire. The chi-square test and comparison of means by analysis of variance were used; significance level adopted was 5% (P < .05). Results Feeding guidelines were provided in the maternity unit to 53% of the families. Breastfeeding was encouraged among 80% of mothers, predominantly in the South (P = .016). However, follow-up after maternity discharge was not appropriately carried out and failure to breast-feed occurred in 78% of families. The feeding tube was used in 21%. According to families, for those who used the ordinary nipple, it was considered the best option by the majority (29%). Conclusion Neonatal feeding in cleft babies is a global challenge. Reports about the difficulties encountered and successful experiences would be helpful to disseminate strategies and stimulate research directed at the large-scale applicability of neonatal feeding for cleft babies on public health. This study detected the need to increase professional training and emphasizes the need for public policies addressing neonatal referral to specialized care wherever possible. It also stimulates research into using an ordinary nipple as another resource for feeding cleft babies and suggests an international discussion about specific recommendations for humanized primary health care.


Jornal De Pediatria | 2011

Estudo multicêntrico da época do diagnóstico de fendas orais

Lívia G. Amstalden-Mendes; Ana Carolina Xavier; Denise K. Antunes; Ana Carolina R. G. Ferreira; Rita Tonocchi; Agnes Cristina Fett-Conte; Raquel N. Silva; Vera H. V. Leirião; Lázara P. C. Caramori; Luiz Alberto Magna; Vera Lúcia Gil-da-Silva-Lopes

OBJECTIVE: To determine the time of diagnosis of typical orofacial clefts in different Brazilian regions and its influence on age at surgical correction. METHOD: This was a prospective, descriptive, cross-sectional study conducted in medical centers in the Southeast, South, and Northeast of Brazil. Trained speech therapists and geneticists interviewed the parents of affected children using a previously validated questionnaire. Epi-Info and SPSS were used for data analysis. Significance level was set at 5% (p < 0.05). RESULTS: The sample consisted of 215 interviews conducted in the following regions: 21.9% (47) in the Southeast, 51.1% (110) in the South, and 27% (58) in the Northeast. Monthly family income was higher in the Southeast (p < 0.05). Cleft lip and palate were found in 61.4% (132) of cases, cleft palate in 20.9% (45), and cleft lip in 17.7% (38). Diagnosis occurred in the maternity ward in 75.3% (162) of cases, during the prenatal period in 14% (30), and after hospital discharge in 10.2% (22). The Southeast had a higher frequency of prenatal diagnosis (27.7%), possibly related to greater purchasing power in this region and greater availability of prenatal investigation. Of all cases diagnosed in the maternity ward, 74.4% occurred in the Northeast. However, no significant difference was found when comparing time of diagnosis, region, and age at first surgery. CONCLUSION: Considering that diagnosis is more common in the maternity ward, local health care teams should be trained in order to effectively improve the initial care of these patients. Although time of diagnosis did not affect age at surgery, it favors the planning of neonatal care and treatment of affected infants.


Revista Brasileira De Otorrinolaringologia | 2007

A mandibulectomia marginal no tratamento dos tumores de loja amigdalina e região retromolar

Maria Beatriz Nogueira Pascoal; José Francisco de Sales Chagas; Nivaldo Alonso; José Luiz Braga de Aquino; Marcus Castro Ferreira; Maria Isabel Nogueira Pascoal; Luiz Alberto Magna

Resection of the ascending ramus of the mandible can result in considerable functional and esthetic damage. AIM: To compare the survival rate and local and regional recurrence in marginal and segmental mandibulectomy for advanced tonsil and retromolar trigone tumours with no mandibular invasion. PLACE AND PERIOD: Reference Head & Neck Service, between October 1994 and December 2001. MATERIAL AND METHOD: 20 stage IV patients undergoing marginal mandibulectomy and 22 undergoing segmental mandibulectomy were compared. CASE STUDY: a contemporary cross-sectional cohort study. RESULTS: Of 20 patients undergoing marginal mandibulectomy, 35% died of the disease, 15% due to local recurrence, 15% due to regional recurrence and 5% due to local and regional recurrence. Of 22 patients undergoing segmentary mandibulectomy, 36,4% died of the disease, 31,8% due to local recurrence and 13,6% due to distant recurrence. The Kaplan-Meier analysis showed a 55% survival rate for the marginal mandibulectomy group, and a 45% survival rate for the segmental group (p= 0.8329). CONCLUSIONS: Analysis of the two groups showed that conservation of the ascending ramus of the mandible, even in advanced lesions with no mandibular involvement, does not increase the recurrence rate.


Journal of Clinical Pathology | 2007

Diagnostic value of combining immunostaining for CD3 and nuclear morphometry in mycosis fungoides

Mariana Montenegro de Melo Lira; André Almeida Schenka; Luiz Alberto Magna; Ana Cristina Cotta; Maria Letícia Cintra; E. M. De Souza; Pierre Brousset; José Vassallo

Background: Mycosis fungoides (MF) is the most common skin lymphoid neoplasm. In initial stages, differential diagnosis of MF from other benign dermal lymphoid infiltrates (BDLI) may be impossible on morphological basis alone. In previous studies, only deletion of CD7 in MF proved to be of diagnostic help, but not the ratio between immunoexpression of CD4 and CD8. Methods: 30 cases of MF and 11 cases of BDLI were analysed, in order to compare morphometric parameters, which could be of diagnostic aid. As CD7 is frequently deleted in MF, immunohistochemical detection of T-cells was made using an antibody to CD3. Images of 100 CD3-positive cells per case in both groups were captured and analysed using a simple computer program for nuclear perimeter, area, diameter and nuclear contour index. Results: All parameters showed statistically significant higher values for MF. Area was the variable with the strongest discriminating power between the two groups of patients. Thus even if morphological evaluation is not accurate to distinguish benign versus malignant dermal lymphoid infiltrates, due to the variability of size and shape of these cells, a more sensitive method promptly shows this difference. Conclusion: Results suggest that morphometry of CD3-positive lymphoid cells may add valuable information in the differential diagnosis of MF and benign dermatoses.


Revista Brasileira De Cirurgia Cardiovascular | 2002

Disfunção endotelial após isquemia global e reperfusão em cirurgia cardíaca com circulação extracorpórea: estudo do papel do magnésio em artérias coronarianas caninas

Marco A. Volpe; João José Carneiro; Luiz Alberto Magna; Fernanda Viaro; Eliana Aparecida Lopes Origuela; Paulo Roberto Barbosa Evora

INTRODUCTION: Hypomagnesemia and ischemia followed by reperfusion often occur in cardiac surgery. Both of them are associated with endothelial dysfunction which interfers negatively with patient evolution. Phisiopatology of these disturbances is similar and involves G-proteins dysfunction. OBJECTIVE: The present study focuses on the endothelial dysfunction consequent to the lesion resulting from global ischemia followed by reperfusion and the potential protective influence of magnesium on the endothelium functional integrity in isolated coronaries of dogs. METHOD: Segments of canine coronary arteries were suspended in organ chambers to measure isometric force. Endothelial dysfunction was evaluated by the ability of these segments to produce nitric oxide changing the initial isometric force. Four groups with six dogs in each one were selected: SEM CEC (control), CEC (110 minutes of perfusion without ischemia), ISQ (45 minutes of ischemia), ISQ/REP (45 minutes of ischemia followed by 60 minutes of reperfusion). The magnesium action was evaluated in three different phases: I (organ chambers with magnesium), II (organ chambers without magnesium) and III (organ chambers with restored magnesium). Three pharmacological agonists were used which represented the main steps involved in the nitric oxide production: the membrane receptor of the endothelial cell - acetylcholine (ACh); transduction of the signal between the receptor and the intracellular processes through the G-protein - sodium fluoride (NaF); liberation of intracellular stocks of calcium - calcium ionophore (A23187). The study of endothelial function was combined with the evaluation of smooth muscle activity dependent on GMPc - sodium nitroprusside (NPS). RESULTS: The major findings of this investigation were as follows: 1) presence of magnesium in priming seemed to attenuate the endothelial dysfunction caused by global ischemia followed by reperfusion; 2) presence of magnesium in the organ chamber (phase I) was associated with the greatest relaxation in response to agonists of the nitric oxide production; 3) removal of magnesium in the organ chamber (phase II) was linked to the reduction in the relaxation intensity in response to agonists of the nitric oxide production; 4) the magnesium restoration to the organ chamber (phase III) allowed restoration of the relaxation observed in the phase I, only in response to the direct stimulation of the G-proteins. For the rest of the remaining agonists, the restoration was associated with the additional reduction in the relaxation intensity; 5) the smooth muscle received the influence of the magnesium concentration in the organ chamber. CONCLUSION: It was concluded that magnesium favorably influences the nitric oxide production by the coronary endothelium attenuating the endothelial dysfunction caused by global ischemia followed by reperfusion.

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I.F.S.F. Boin

State University of Campinas

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Luiz Sergio Leonardi

State University of Campinas

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Agnes Cristina Fett-Conte

Faculdade de Medicina de São José do Rio Preto

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M.H.S. Kraemer

State University of Campinas

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