Licínio Esmeraldo da Silva

Expression of Bcl-2 family proteins and associated clinicopathologic factors predict survival outcome in patients with oral squamous cell carcinoma.

The aims of this study were to assess the expression levels of three proteins involved in apoptosis--Bcl-2, Bcl-X, and Bax--and evaluate their relationship with clinicopathologic features and survival in oral squamous cell carcinoma (OSCC). Immunohistochemistry was used to evaluate protein expression in 53 primary OSCCs treated by radical surgery with free margins at a single institution in 1999. Histologic specimens were graded and analyzed for perineural invasion, lymphocytic infiltrate, and pattern of invasion. Digital image analysis was performed to quantify immunostaining. Survival was analyzed using the Kaplan-Meier method and Coxs proportional hazard model. Cancer-specific 5-year survival (CSS) was 61% (56% overall survival (OS), and 51% disease-free interval (DFI)). Kaplan-Meier analysis identified pathologic stage (p=0.0007, log-rank test, OS), negative nodes status (pN) (p<0.0001, log-rank test, OS), presence of lymphocytic infiltrate (p=0.0084, log-rank test, OS), and high Bax expression (p=0.025, log-rank test, OS) to each be associated with both better OS and CSS. Tongue tumors (p=0.0179, log-rank test), worst pattern of invasion (p=0.0293, log-rank test), lack of lymphocytic infiltrate (p=0.0328, log-rank test), perineural invasion (p=0.0448, log-rank test), poorly differentiated tumors (p=0.0318, log-rank test), and low Bcl-X expression (p=0.044, log-rank test) were all associated with a low DFI. Cox regression found pN, lymphocytic infiltrate, and Bax expression to be independent prognostic factors for OS and CSS, whereas lymphocytic response and tongue tumors were predictors of DFI. Bcl-2 expression emerged as an independent marker of favorable CSS. Lymphocytic infiltrate was the most meaningful histopathologic parameter in survival analysis, whereas expression of Bcl-2 family members seems to be an important marker of a favorable prognosis in OSCC.

Oral squamous cell carcinoma grading systems – analysis of the best survival predictor

BACKGROUND The TNM system has been used for decades in an attempt to predict clinical behavior and appropriate therapy for oral squamous cell carcinomas. Histopathologic classifications can be useful as an additional predictive tool. The purpose of this study was to apply four grading systems (Multiparameter Grading System, Malignancy Grading of the Deep Invasive Margins, World Health Organization grading system, and Histologic Risk Assessment) to oral squamous cell carncinomas and evaluate each system based on clinicopathologic parameters and patient survival. METHODS The files of 53 patients diagnosed with primary oral squamous cell carcinoma at the Brazilian National Cancer Institute were evaluated. All hematoxylin and eosin-stained slides were reviewed to confirm the original diagnosis and to determine histopathologic grading. Clinicopathologic information was obtained from medical records and tumor registries. Statistical analysis was performed using Fishers exact test or the chi-square test, the Kaplan-Meier method, and the log-rank test. RESULTS The Multiparameter Grading System was statistically associated with pathologic staging (P = 0.02) and lymph node involvement (P = 0.0009). Differences in overall 5-year survival were significant for Histologic Risk Assessment (P = 0.015), pathologic staging (P = 0.001), lymph node status (P < 0.0001), and recurrence (P = 0.0001). Differences in cancer-specific 5-year survival were significant for Histologic Risk Assessment (P = 0.029), pathologic staging (P = 0.002), lymph node involvement (P < 0.0001), and recurrence (P < 0.0001). Poorly differentiated tumors were associated with the worst disease-free survival (P = 0.031) and recurrence (P = 0.043). CONCLUSION Of the grading systems evaluated, Histologic Risk Assessment demonstrated the best results for survival prediction in oral squamous cell carcinoma.

Antimicrobial activity of calcium hydroxide pastes on Enterococcus faecalis cultivated in Root Canal Systems

The effectiveness of calcium hydroxide pastes: Calen and PMCC-Calen associated to chemo-mechanical preparation was assessed on Enterococcus faecalis grown within root canals. Seventy incisors were inserted into TSB medium, sterilized and contaminated with E. faecalis. Culture medium was replaced each 24 h and incubated at 37 degrees C for 72 h. After chemo-mechanical preparation, root canals were filled with Calen or PMCC-Calen (7 or 14 days). Pastes were removed and teeth were inserted into test tubes containing Enterococcosel broth. Calen paste (maintained for 7 and 14 days) induced 70% elimination of enterococci and PMCC-Calen 100% elimination only after maintenance for 14 days. These medications were significantly more effective (p<0.001) than chemo-mechanical protocol alone and PMCC-Calen maintained for 7 days, both incapable to eliminate the viability of enterococci. Calcium hydroxide pastes demonstrated important adjuvant effects in the elimination of enterococci during chemo-mechanical preparation of root canal systems. When associated with PMCC, calcium hydroxide pastes should be maintained for at least 14 days.

Reproducibility of Immunostaining Quantification and Description of a New Digital Image Processing Procedure for Quantitative Evaluation of Immunohistochemistry in Pathology

Quantification of immunostaining is a widely used technique in pathology. Nonetheless, techniques that rely on human vision are prone to inter- and intraobserver variability, and they are tedious and time consuming. Digital image analysis (DIA), now available in a variety of platforms, improves quantification performance: however, the stability of these different DIA systems is largely unknown. Here, we describe a method to measure the reproducibility of DIA systems. In addition, we describe a new image-processing strategy for quantitative evaluation of immunostained tissue sections using DAB/hematoxylin-stained slides. This approach is based on image subtraction, using a blue low pass filter in the optical train, followed by digital contrast and brightness enhancement. Results showed that our DIA system yields stable counts, and that this method can be used to evaluate the performance of DIA systems. The new image-processing approach creates an image that aids both human visual observation and DIA systems in assessing immunostained slides, delivers a quantitative performance similar to that of bright field imaging, gives thresholds with smaller ranges, and allows the segmentation of strongly immunostained areas, all resulting in a higher probability of representing specific staining. We believe that our approach offers important advantages to immunostaining quantification in pathology.

Evaluation of mast cells in periapical cysts, dentigerous cysts, and keratocystic odontogenic tumors

BACKGROUND Several cell types are associated with the development of cystic and tumoral odontogenic lesions. Among inflammatory cells, mast cells can be associated with their pathogenesis. The aim of this study was to analyze mast cells in periapical cysts, dentigerous cysts, and keratocystic odontogenic tumors. METHODS Tissue sections were submitted to toluidine blue staining and immunohistochemistry with antibody anti-tryptase (clone G3). Mast cells were quantitated using Image-Pro Plus software to obtain the mean number of mast cells in three regions: epithelial, superficial portion of the fibrous wall and deep portion of the fibrous wall from 20 periapical cysts, 20 dentigerous cysts (six non-inflamed and 14 inflamed) and 20 keratocystic odontogenic tumors (four non-inflamed and 16 inflamed). RESULTS The mean number of mast cells detected per lesion by immunohistochemistry (4.1) was higher than by histochemistry (1.5) (P<0.0001). Inflamed dentigerous cysts and keratocystic odontogenic tumors showed a higher mean number of mast cells than non-inflamed lesions in all regions. The deep region from all cysts showed the highest mean number of degranulated mast cells, except for non-inflamed keratocystic odontogenic tumors analyzed by immunohistochemistry. CONCLUSIONS Immunohistochemical staining detected higher number of mast cells than histochemistry. The higher number of mast cells observed in inflamed lesions could indicate the participation of these cells in the inflammatory response in odontogenic lesions. The prevalence of degranulated mast cells in the deep region suggests intense activity of these cells, possibly related to growth of cystic lesions.

The influence of medication on salivary flow of the elderly: preliminary study.

OBJECTIVE This study was to evaluate the influence of medications on unstimulated and stimulated salivary flow in elderly men and women. BACKGROUND Several diseases and conditions are associated with decreasing salivary flow. Medications can be risk factors for hyposalivation due to the effect particular drug categories. METHODS Seventy-five elderly of both gender (sixty years old or over) from the Geriatric Dental Clinic at the Federal Fluminense University Dental School, were interviewed about their health status and chronic use of medication. After the interview, unstimulated and stimulated saliva were collected from each subject. The collection time was five minutes, and the flow rate was calculated as ml/min. RESULTS The mean unstimulated salivary flow was 0.25 ml/min for women and 0.30 ml/min for men, while the mean for stimulated salivary flow was 1.23 ml/min for women and 1.31 ml/min for men, without both differences being non-significant (p > 0.05). The difference between the mean production of unstimulated and stimulated salivary flow was statistically significant, regardless of gender (p < 0.01). A significant reduction of stimulated salivary flow was observed with the usage of cardiovascular agents (p < 0.05). CONCLUSION Drugs used in cardiovascular disease influence the flow of stimulated saliva.

Evaluation of Inflammatory Response of EDTA, EDTA-T, and Citric Acid in Animal Model

INTRODUCTION The biocompatibility of chelating agents and organic acids have been explained by a variety of methods, and suggestions for use have been based more on clinical observations and physicochemical properties than on biological aspects. The present study aimed to evaluate the inflammatory response of 17% EDTA, 17% EDTA-T, and 10% citric acid in bony defect created in rat jaws. METHODS Mandibular through and through critical size defects were created bilaterally in 60 rats. Fibrinol (Baldacchi SA, São Paulo, Brazil), a cube-shaped compound of absorbable bovine fibrin foam and sodium chloride, was used as a carrier of the substances. One side had received Fibrinol (control), whereas the opposite side had received Fibrinol soaked with each substance on the 1st, on the 7th, on the 14th, and on the 28th day (n=5 for each day). Hemijaws were prepared for light microscopy, and samples were stained with hematoxylin and eosin. Digitized images were analyzed with a morphometric software (ImageJ; National Institute of Mental Health, Bethesda, MD). to obtain the number of inflammatory cells per area. Comparisons were performed by using the Kruskal-Wallis test (p=0.05). RESULTS For all days, 10% citric acid and 17% EDTA-T showed, respectively, the lowest and highest number of inflammatory cells per area. All tested substances and controls showed the highest inflammatory cell response on the 14th day. CONCLUSION Among the tested substances, 10% citric acid proved to be the less aggressive tested solution at 14 days. At 28 days, all solutions were similar, but EDTA-T kept showing the higher number of inflammatory cells.

Análise de sobrevida global em pacientes diagnosticados com carcinoma de células escamosas de boca no INCA no ano de 1999

O carcinoma de celulas escamosas de boca compreende cerca de 90 a 95% de todas as neoplasias malignas da boca e e um dos tipos de câncer mais frequentes no Brasil. O indice de sobrevida em 5 anos e baixo e permaneceu estavel nas ultimas decadas, apesar dos avancos nas terapias. O objetivo deste estudo foi analisar o perfil e a sobrevida global dos pacientes diagnosticados com carcinoma de celulas escamosas de boca no ano de 1999 no Instituto Nacional de Câncer. Dos 320 pacientes incluidos no estudo, 79,4% eram homens. A idade media foi de 56,7 anos, e 82,2% deles fumavam e/ou bebiam. A lingua, seguida do assoalho de boca foram os locais mais acometidos. A maioria (68,9%) dos pacientes foi diagnosticada em estadios tardios e submetida a radioterapia exclusiva (53,6%). A sobrevida media no periodo do estudo foi de 29,4 meses. Os pacientes dos estadios iniciais apresentaram maior sobrevida, assim como aqueles submetidos apenas a cirurgia como forma de tratamento e os que nao apresentaram linfonodos acometidos ao diagnostico. Tumores localizados em palato duro e mucosa jugal apresentaram pior prognostico. Foram fatores preditivos independentes de melhor sobrevida os tumores T1 ou T2 (p=0,001), sem acometimento de linfonodos (p=0,012) e nao localizados em mucosa jugal (p=0,021). O diagnostico do câncer oral ainda se faz em estadios tardios, o que influencia negativamente a sobrevida global dos pacientes. Maior enfase deve ser dada a capacitacao dos profissionais para o reconhecimento precoce do câncer e a conscientizacao da populacao de risco.

Ridge bone maintenance in human after extraction.

Purpose:The aim of this study was to evaluate, clinically and histologically, the tissues formed in human alveolar sockets filled with bovine morphogenetic protein/bovine organic matrix (BOM) and absorbable membrane (AM) immediately after extraction. Materials:Forty-six human alveolar sockets, exhibiting buccal bone defects were selected for this study. Group 1 received no biomaterial to serve as control. Sockets from group 2 were filled with bovine bone morphogenetic protein (bBMP) associated with bOM. The association of bBMP/bOM/AM filled the alveolar defects from group 3. AM was placed over the defects from group 4. Clinical evaluation analyzed ridge width before biomaterial filling and 4 months after filling. Fifteen specimens were collected from groups 2, 3, and 4 for histologic analyses. Results:Clinical results showed no significant augmentation on the control group (−0.16 ± 0.28 mm). All test sites, groups 2, 3, and 4, showed relevant ridge width augmentation (3.0 ± 0.5 mm, 2.4 ± 0.3 mm, and 2.9 ± 0.6 mm, respectively) and no resorption. Histologically, all experimental alveolar sockets showed active bone formation with osteoid, osteoblasts, and cell differentiation. Conclusion:On the basis of this study, we concluded that bBMP/bOM with or without AM could preserve the ridge showing viable bone formation for future implant placement.

High prevalence of Staphylococcus aureus and methicillin-resistant S. aureus colonization among healthy children attending public daycare centers in informal settlements in a large urban center in Brazil

BackgroundIn the past decade methicillin-resistant Staphylococcus aureus (MRSA) has become increasingly prevalent in community settings. Attending a daycare center (DCC) is a known risk factor for colonization with MRSA. Brazil operates free, public DCCs for low-income families, some of which are located in census tracts defined by the Brazilian Census Bureau as informal settlements (aglomerados subnormais, AGSN). Physical and demographic characteristics of AGSNs suggest that S. aureus colonization prevalence would be higher, but little is known about the prevalence of MRSA in these settings.MethodsWe conducted a cross-sectional study to assess risk factors for S. aureus and MRSA colonization among children attending DCCs located in AGSN vs non-AGSN. Nasal swabs were collected from children aged three months to six years in 23 public DCCs in Niterói, Brazil between August 2011 and October 2012.ResultsOf 500 children enrolled in the study, 240 (48%) were colonized with S. aureus and 31 (6.2%) were colonized with MRSA. Children attending DCCs in AGSNs were 2.32 times more likely to be colonized with S. aureus (95% CI: 1.32, 4.08), and 3.27 times more likely to be colonized with MRSA than children attending non-AGSN DCCs (95% CI: 1.52, 7.01), adjusted for confounding variables.ConclusionS. aureus and MRSA colonization prevalence among children attending DCCs in informal settlement census tracts was higher than previously reported in healthy pre-school children in Latin America. Our data suggest that transmission may occur more frequently in DCCs rather than at home, highlighting the importance of DCCs in AGSNs as potential MRSA reservoirs. This finding underscores the importance of local epidemiologic surveillance in vulnerable AGSN communities.