Dominantly inherited micro-satellite instable cancer - the four Lynch syndromes - an EHTG, PLSD position statement.

The recognition of dominantly inherited micro-satellite instable (MSI) cancers caused by pathogenic variants in one of the four mismatch repair (MMR) genes MSH2, MLH1, MSH6 and PMS2 has modified our understanding of carcinogenesis. Inherited loss of function variants in each of these MMR genes cause four dominantly inherited cancer syndromes with different penetrance and expressivities: the four Lynch syndromes. No person has an "average sex "or a pathogenic variant in an "average Lynch syndrome gene" and results that are not stratified by gene and sex will be valid for no one. Carcinogenesis may be a linear process from increased cellular division to localized cancer to metastasis. In addition, in the Lynch syndromes (LS) we now recognize a dynamic balance between two stochastic processes: MSI producing abnormal cells, and the host's adaptive immune system's ability to remove them. The latter may explain why colonoscopy surveillance does not reduce the incidence of colorectal cancer in LS, while it may improve the prognosis. Most early onset colon, endometrial and ovarian cancers in LS are now cured and most cancer related deaths are after subsequent cancers in other organs. Aspirin reduces the incidence of colorectal and other cancers in LS. Immunotherapy increases the host immune system's capability to destroy MSI cancers. Colonoscopy surveillance, aspirin prevention and immunotherapy represent major steps forward in personalized precision medicine to prevent and cure inherited MSI cancer.

Mutational spectrum of breast cancer susceptibility genes among women ascertained in a cancer risk clinic in Northeast Brazil.

PURPOSE: There is a paucity of data on the spectrum and prevalence of pathogenic variants among women of African ancestry in the Northeast region of Brazil. METHODS: We performed BROCA panel sequencing to identify inherited loss-of-function variants in breast cancer susceptibility genes among 292 Brazilian women referred to a single institution cancer risk assessment program. RESULTS: The study included a convenient cohort of 173 women with invasive breast cancer (cases) and 119 women who were cancer-free at the time of ascertainment. The majority of the women self-reported as African-descended (67% for cases and 90.8% for unaffected volunteers). Thirty-seven pathogenic variants were found in 36 (20.8%) patients. While the spectrum of pathogenic variants was heterogeneous, the majority (70.3%) of the pathogenic variants were detected in high-risk genes BRCA1, BRCA2, PALB2, and TP53. Pathogenic variants were also found in the ATM, BARD1, BRIP1, FAM175A, FANCM, NBN, and SLX4 genes in 6.4% of the affected women. Four recurrent pathogenic variants were detected in 11 patients of African ancestry. Only one unaffected woman had a pathogenic variant in the RAD51C gene. Different risk assessment models examined performed well in predicting risk of carrying germline loss-of-function variants in BRCA1 and/or BRCA2 in breast cancer cases. CONCLUSION: The high prevalence and heterogenous spectrum of pathogenic variants identified among self-reported African descendants in Northeast Brazil is consistent with studies in other African ancestry populations with a high burden of aggressive young onset breast cancer. It underscores the need to integrate comprehensive cancer risk assessment and genomic testing in the management of newly diagnosed Black women with breast cancer across the African Diaspora, enabling improved cancer control in admixed underserved and understudied populations.

MLH1 intronic variants mapping to + 5 position of splice donor sites lead to deleterious effects on RNA splicing.

Germline pathogenic variants in the DNA mismatch repair genes (MMR): MLH1, MSH2, MSH6, and PMS2, are causative of Lynch syndrome (LS). However, many of the variants mapping outside the invariant splice site positions (IVS ± 1, IVS ± 2) are classified as variants of unknown significance (VUS). Three such variants (MLH1 c.588+5G>C, c.588+5G>T and c.677+5G>A) were identified in 8 unrelated LS families from Argentina, Brazil and Chile. Herein, we collected clinical information on these families and performed segregation analysis and RNA splicing studies to assess the implication of these VUS in LS etiology. Pedigrees showed a clear pattern of variant co-segregation with colorectal cancer and/or other LS-associated malignancies. Tumors presented deficient expression of MLH1-PMS2 proteins in 7/7 of the LS families, and MSI-high status in 3/3 cases. Moreover, RNA analyses revealed that c.588+5G>C and c.588+5G>T induce skipping of exon 7 whereas c.677+5G>A causes skipping of exon 8. In sum, we report that the combined clinical findings in the families and the molecular studies provided the evidences needed to demonstrate that the three MLH1 variants are causative of LS and to classify c.588+5G>C and c.677+5G>A as class 5 (pathogenic), and c.588+5G>T as class 4 (likely-pathogenic). Our findings underline the importance of performing clinical and family analyses, as well as RNA splicing assays in order to determine the clinical significance of intronic variants, and contribute to the genetic counseling and clinical management of patients and their relatives.

Humoral and cellular immune responses in mice against secreted and somatic antigens from a Corynebacterium pseudotuberculosis attenuated strain: Immune response against a C. pseudotuberculosis strain.

BACKGROUND: Corynebacterium pseudotuberculosis is the etiologic agent of caseous lymphadenitis (CL), a chronic disease that affects goats and sheep. CL is characterized by the formation of granulomas in lymph nodes and other organs, such as the lungs and liver. Current knowledge of CL pathogenesis indicates that the induction of humoral and cellular immune responses are fundamental to disease control. The aim of this study was to evaluate the humoral and cellular immune responses in BALB/c mice inoculated with a C. pseudotuberculosis strain isolated in the state of Bahia, Brazil. RESULTS: The lymphocyte proliferation and in vitro production of IFN-γ, IL-4, IL-10, IL-12 and nitric oxide by spleen cells stimulated with secreted and somatic antigens from the studied strain were evaluated. IgG subclasses were also analyzed. Results showed a significant increase of Th1-profile cytokines after 60 days post-inoculation, as well as an important humoral response, represented by high levels of IgG2a and IgG1 against C. pseudotuberculosis. CONCLUSION: The T1 strain of C. pseudotuberculosis was shown to induce humoral and cellular immune responses in BALB/c mice, but, even at a dosage of 1x10(7) CFU, no signs of the disease were observed.

BRCA1 and BRCA2 rearrangements in Brazilian individuals with Hereditary Breast and Ovarian Cancer Syndrome.

Approximately 5-10% of breast cancers are caused by germline mutations in high penetrance predisposition genes. Among these, BRCA1 and BRCA2, which are associated with the Hereditary Breast and Ovarian Cancer (HBOC) syndrome, are the most frequently affected genes. Recent studies confirm that gene rearrangements, especially in BRCA1, are responsible for a significant proportion of mutations in certain populations. In this study we determined the prevalence of BRCA rearrangements in 145 unrelated Brazilian individuals at risk for HBOC syndrome who had not been previously tested for BRCA mutations. Using Multiplex Ligation-dependent Probe Amplification (MLPA) and a specific PCR-based protocol to identify a Portuguese founder BRCA2 mutation, we identified two (1,4%) individuals with germline BRCA1 rearrangements (c.547+240_5193+178del and c.4675+467_5075-990del) and three probands with the c.156_157insAlu founder BRCA2 rearrangement. Furthermore, two families with false positive MLPA results were shown to carry a deleterious point mutation at the probe binding site. This study comprises the largest Brazilian series of HBOC families tested for BRCA1 and BRCA2 rearrangements to date and includes patients from three regions of the country. The overall observed rearrangement frequency of 3.44% indicates that rearrangements are relatively uncommon in the admixed population of Brazil.

Flavonoids from the Brazilian plant Croton betulaster inhibit the growth of human glioblastoma cells and induce apoptosis

Abstract This study investigated the effects of the flavonoids 5-hydroxy-7,4′-dimethoxyflavone, casticin, and penduletin, isolated from Croton betulaster Müll Arg., Euphorbiaceae, a plant utilized in popular medicine in Brazil, on the growth and viability of the human glioblastoma cell line GL-15. We observed that 5-hydroxy-7,4′-dimethoxyflavone and casticin were not toxic to GL-15 cells after 24 h of exposure. However, casticin and penduletin inhibited the metabolic activity of glioblastoma cells significantly at a concentration of 10 µM (p ≤ 0.05). Flavonoids casticin and penduletin also induced a significant and dose-dependent growth inhibition beginning at 24 h of exposure, and the most potent flavonoid was penduletin. It was also observed that penduletin and casticin induced an enlargement of the cell body and a reduction of cellular processes, accompanied by changes in the pattern of expression of the cytoskeletal protein vimentin. Signs of apoptosis, such as the externalization of membrane phosphatidyl serine residues, nuclear condensation, and fragmentation, were also detected in cells treated with 50–100 µM flavonoids. Our results indicate that flavonoids extracted from C. betulaster present antitumoral activity to glioblastoma cells, with penduletin proving to be the most potent of the tested flavonoids. Our results also suggest that these molecules may be promising supplementary drugs for glioblastoma treatment.

Avaliação imuno-histoquímica de células de Langerhans e densidade microvascular em ameloblastomas / Immunohistochemistry assessment of Langerhans cells and microvessel density in ameloblastomas

Este estudo objetivou avaliar e correlacionar a microdensidade vascular (MDV) e a quantidade de células de Langerhans (CLs) presentes em ameloblastoma (AB). Vinte e cinco lesões em blocos parafinados de AB foram analisados através de técnica imuno-histoquímica onde foram empregados dois marcadores, anti-CD1a e anti-CD207, para quantificar as células de Langerhans, e o CD34 para avaliar a MDV. A imunomarcação para o CD1a, CD207 e CD34 foi observada em 88% dos casos analisados, mostrando uma significativa associação estatística (p = 0.001, FisherÆs test). Não foi observada correlação estatística entre MDV e CLs, nem relação entre as imunomarcações com os tipos unicístico e sólido. No entanto, a imunomarcação pelo CD1a e CD207 teve uma correlação estatisticamente significante (p valor = 0,001, teste de Spearmann). As CLs e a MDV parecem influenciar na imunopatogênese do ameloblastoma, apesar de não ter sido encontrada correlação estatisticamente significante entre esses dois achados, mas possivelmente por essas células dendríticas produzirem citocinas inflamatórias indutoras de destruição óssea e mitose celular.

The aim of this study was to assess and correlate microvessel density (MVD) and the quantity of Langerhans cells (LC) present in ameloblastomas (AB). Twenty-five paraffin-embedded blocks of AB lesions were analyzed using the immunohistochemical technique in which anti-CD1a and anti-CD207 markers were used to quantify the Langerhans cells and the CD34 marker to assess MVD. In 88% of the analyzed cases immunostaining was observed for CD1a, CD207, and CD34, with statistically significant association (p = 0.001, FisherÆs test). No statistical correlation was observed between MVD and LCs nor between immunostainings with solid and unicyst ameloblastoma. However, statistically significant correlation (p value = 0,001, Spearman test) was observed between CD1a and CD207 immunostaining. The LCs and MVD seemed to influence immunopathogenesis of ameloblastoma, although no statistically significant correlation was observed between these two findings, probably because these dendritic cells produce inflammatory cytokines that induce bone destruction and cell mitosis.

Immunolocalization of FGF-2 and VEGF in rat periodontal ligament during experimental tooth movement.

OBJECTIVE: This article aimed at identifying the expression of fibroblast growth factor-2 (FGF-2) and vascular endothelial growth factor (VEGF) in the tension and pressure areas of rat periodontal ligament, in different periods of experimental orthodontic tooth movement. METHODS: An orthodontic force of 0.5 N was applied to the upper right first molar of 18 male Wistar rats for periods of 3 (group I), 7 (group II) and 14 days (group III). The counter-side first molar was used as a control. The animals were euthanized at the aforementioned time periods, and their maxillary bone was removed and fixed. After demineralization, the specimens were histologically processed and embedded in paraffin. FGF-2 and VEGF expressions were studied through immunohistochemistry and morphological analysis. RESULTS: The experimental side showed a higher expression of both FGF-2 and VEGF in all groups, when compared with the control side (P < 0.05). Statistically significant differences were also found between the tension and pressure areas in the experimental side. CONCLUSION: Both FGF-2 and VEGF are expressed in rat periodontal tissue. Additionally, these growth factors are upregulated when orthodontic forces are applied, thereby suggesting that they play an important role in changes that occur in periodontal tissue during orthodontic movement.

Immunolocalization of FGF-2 and VEGF in rat periodontal ligament during experimental tooth movement

OBJECTIVE: This article aimed at identifying the expression of fibroblast growth factor-2 (FGF-2) and vascular endothelial growth factor (VEGF) in the tension and pressure areas of rat periodontal ligament, in different periods of experimental orthodontic tooth movement. METHODS: An orthodontic force of 0.5 N was applied to the upper right first molar of 18 male Wistar rats for periods of 3 (group I), 7 (group II) and 14 days (group III). The counter-side first molar was used as a control. The animals were euthanized at the aforementioned time periods, and their maxillary bone was removed and fixed. After demineralization, the specimens were histologically processed and embedded in paraffin. FGF-2 and VEGF expressions were studied through immunohistochemistry and morphological analysis. RESULTS: The experimental side showed a higher expression of both FGF-2 and VEGF in all groups, when compared with the control side (P < 0.05). Statistically significant differences were also found between the tension and pressure areas in the experimental side. CONCLUSION: Both FGF-2 and VEGF are expressed in rat periodontal tissue. Additionally, these growth factors are upregulated when orthodontic forces are applied, thereby suggesting that they play an important role in changes that occur in periodontal tissue during orthodontic movement. .

OBJETIVO: o objetivo desse estudo foi identificar a expressão do fator de crescimento de fibroblastos 2 (FGF-2) e do fator de crescimento vascular endotelial (VEGF) nos lados de tensão e pressão do ligamento periodontal de ratos, durante movimento ortodôntico experimental, em diferentes períodos de tempo. MÉTODOS: uma força ortodôntica de 0,5N foi aplicada no primeiro molar superior direito de 18 ratos Wistar machos, por períodos de 3 (grupo I), 7 (grupo II) e 14 dias (grupo III). O primeiro molar do lado oposto foi utilizado como controle. Os animais foram sacrificados nos períodos de tempo mencionados, sendo a arcada superior removida e fixada. Após a desmineralização, os espécimes foram processados histologicamente e embebidos em parafina. A expressão do FGF-2 e do VEGF foram estudadas por meio de análise imuno-histoquímica. RESULTADOS: o ligamento periodontal dos dentes submetidos à movimentação ortodôntica mostraram maior expressão tanto de FGF-2 quanto de VEGF, em todos os grupos experimentais, quando comparados com os dentes do lado controle (p < 0,05). Diferenças estatisticamente significativas entre os lados de tensão e pressão também foram encontradas nos dentes submetidos à movimentação ortodôntica. CONCLUSÕES: tanto o FGF-2 quanto o VEGF são expressos no tecido periodontal de ratos, e esses fatores de crescimento são aumentados quando forças ortodônticas são aplicadas, sugerindo que esses desempenham um papel importante na reorganização do periodonto durante o movimento ortodôntico. .

Immunohistochemistry assessment of Langerhans cells and microvascular density in oral squamous cell carcinomas / Avaliação imuno-histoquímica de células de Langerhans e densidade microvascular em carcinoma oral de células escamosas

The aim of this study was to assess and correlate microvascular density (MVD) and the quantity of Langerhans cells (LC) present in oral squamous cell carcinoma (OSCC), well as the correlation between this microvascular density and number of Langerhans cells (LCs) with the intensity of the infiltrate, the histologic grading and staging, according to the TNM system. Twenty-three paraffin-embedded blocks of SCC lesions were analyzed using the immunohistochemical technique in which the two anti-CD1a and anti-CD207 markers were used to quantify the Langerhans cells and the CD34 marker to assess MVD. Immunostaining for CD1a, CD207 and CD34 was observed in 100% of the cases analyzed, showing a statistically significant association (p = 0.0001, Fisher’s test). No statistical correlation between MVD and LC or between immunostainings and histological grading of malignancy were found. However, immunostaining for CD1a and CD207 showed a statistically significant correlation (p value = 0.001, Spearman test) and a positive correlation was found between MVD and lymph node involvement. The LCs and MVD seem to involved in immunopathogenesis of oral carcinoma, although no statistically significant correlation was found between these two findings

O objetivo deste estudo foi avaliar e correlacionar a densidade microvascular (MVD) e a quantidade de células de Langerhans (LC) presente no carcinoma epidermoide de boca (CEB), bem como a correlação entre esta densidade microvascular e número das células de Langerhans (CL), com a intensidade do infiltrado, a classificação histológica e de teste, de acordo com o sistema TNM. Vinte e três blocos de parafina-encaixados de lesães SCC foram analisados utilizando a técnica de imuno-histoquímica em que os dois marcadores anti-CD1a e anti-CD207 foram usados para quantificar as células de Langerhans e o marcador CD34 para avaliar MVD. A imunocoloração para CD1a, CD207 e CD34 foi observada em 100% dos casos analisados, demonstrando uma associação estatisticamente significativa (p = 0,0001, teste de Fisher). Não houve correlação estatística entre MVD e LC ou entre imunomarcações e gradação histológica de malignidade foram encontrados. No entanto, a imunocoloração para CD1a e CD207 mostraram uma correlação estatisticamente significativa (p = 0,001, teste de Spearman) e foi encontrada uma correlação positiva entre MVD e comprometimento de linfonodos. O LCs e MVD parecem envolvidos em imunopatogênese de carcinoma oral, embora não foi encontrada correlação estatisticamente significativa entre estes dois resultados.

Stem cells and their niches: importance in tissue engineering applied to dentistry / Células-tronco e seus nichos: importância na engenharia de tecidos aplicada à odontologia

Niches are special microenvironments in tissue where stem cells are located. At these sites, which are a compound of stromal cells, extracellular matrix and soluble factors, complex molecular interactions that maintain the essential properties of stem cells occur, such as self-renewal and differentiation into multiple lineages, according to the organism?s needs. Some adult stem cell niches have already been described, but the majority of them remain unclear, including the dental pulp stem cell niches. Dental pulp stem cells have been isolated from deciduous and permanent teeth and have the potential to self-renew and differentiate. However, little is known about the exact anatomic location of these cells, and the relationship between stem cells and surrounding cells in dental pulp. Understanding how stem cells behave in the niche is extremely important in order to extract these cells from their natural habitat, expand them in vitro and transplant the stem cells back to the patient, to repair and/or regenerate tissues and organs, with no risks to the individual?s integrity. Likewise, the knowledge of stem cell biology is crucial to the development of stem cell therapies, based on tissue engineering applied to dentistry, seeking the regeneration of dental tissues damaged or lost by caries, trauma or genetic diseases.

Os nichos são microambientes especiais nos tecidos onde células-tronco de várias origens estão localizadas. Nestes sítios específicos, formados por vários tipos de células, matriz extracelular e fatores solúveis, complexas interações moleculares ocorrem para que a célulatroncomantenha sua capacidade de autorrenovação e permaneça no seu estado indiferenciado ou se especialize em determinada linhagemcelular, atendendo desta maneira as necessidades do organismo. Alguns nichos de células-tronco adultas já foram descritos, embora a maioriapermaneça desconhecida, como o das células-tronco pulpares. As células-tronco pulpares, já foram isoladas tanto de dentes decíduos comode permanentes e apresentam as características essenciais de uma célula-tronco, como capacidade de autorrenovação e multi-diferenciação.Apesar disso, pouco se sabe a respeito da localização anatômica destas células na polpa, assim como as possíveis interações funcionais entreas células-tronco pulpares e as células do estroma circundante. O entendimento de como as células-tronco interagem com o microambienteonde estão inseridas é essencial para que se possa extrair as mesmas do seu habitat natural, cultivá-las in vitro e aplicá-las em diferentessítios para que promovam o reparo e/ou regeneração de tecidos e órgãos, sem que isso represente um risco à integridade do organismo. Da mesma forma, o conhecimento de como estas células se comportam e respondem ao meio é fundamental para o desenvolvimento de terapias baseadas na utilização de células-tronco, que através da engenharia de tecidos aplicada à odontologia, visa à reestruturação de tecidos dentários danificados e/ou perdidos por cárie, trauma ou distúrbios genéticos.

Immunological characteristics of mesenchymal stem cells.

Although bone marrow is the main source, mesenchymal stem cells have already been isolated from various other tissues, such as the liver, pancreas, adipose tissue, peripheral blood and dental pulp. These plastic adherent cells are morphologically similar to fibroblasts and have a high proliferative potential. This special group of cells possesses two essential characteristics: self-renewal and differentiation, with appropriate stimuli, into various cell types. Mesenchymal stem cells are considered immunologically privileged, since they do not express costimulatory molecules, required for complete T cell activation, on their surface. Several studies have shown that these cells exert an immunosuppressive effect on cells from both innate and acquired immunity systems. Mesenchymal stem cells can regulate the immune response in vitro by inhibiting the maturation of dendritic cells, as well as by suppressing the proliferation and function of T and B lymphocytes and natural killer cells. These special properties of mesenchymal stem cells make them a promising strategy in the treatment of immune mediated disorders, such as graft-versus-host disease and autoimmune diseases, as well as in regenerative medicine. The understanding of immune regulation mechanisms of mesenchymal stem cells, and also those involved in the differentiation of these cells in various lineages is primordial for their successful and safe application in different areas of medicine.

Immunological characteristics of mesenchymal stem cells

Although bone marrow is the main source, mesenchymal stem cells have already been isolated from various other tissues, such as the liver, pancreas, adipose tissue, peripheral blood and dental pulp. These plastic adherent cells are morphologically similar to fibroblasts and have a high proliferative potential. This special group of cells possesses two essential characteristics: self-renewal and differentiation, with appropriate stimuli, into various cell types. Mesenchymal stem cells are considered immunologically privileged, since they do not express costimulatory molecules, required for complete T cell activation, on their surface. Several studies have shown that these cells exert an immunosuppressive effect on cells from both innate and acquired immunity systems. Mesenchymal stem cells can regulate the immune response in vitro by inhibiting the maturation of dendritic cells, as well as by suppressing the proliferation and function of T and B lymphocytes and natural killer cells. These special properties of mesenchymal stem cells make them a promising strategy in the treatment of immune mediated disorders, such as graft-versus-host disease and autoimmune diseases, as well as in regenerative medicine. The understanding of immune regulation mechanisms of mesenchymal stem cells, and also those involved in the differentiation of these cells in various lineages is primordial for their successful and safe application in different areas of medicine.

Pesquisa de interferon gama em tecido periodontal de ratos submetidos à movimentação dentária induzida / Gamma-interferon investigation in rat periodontal tissue under induced dental movement

INTRODUÇÃO: durante o tratamento ortodôntico, um processo inflamatório é induzido, desencadeando uma série de eventos bioquímicos que resultam na movimentação dentária. Estímulos como a hipóxia e a deformação mecânica são os principais fatores responsáveis pela quebra da homeostasia celular, resultando em estresse e liberação de diversos mediadores importantes para o movimento do dente. Para que a remodelação óssea ocorra durante o tratamento ortodôntico, fatores reguladores,como subprodutos do ácido araquidônico e citocinas,são liberados.Ao interferon gama (INF-γ , uma citocina principal liberada após a indução da resposta imune adaptativa, é atribuída a função de atrair os macrófagos, que auxiliam na remoção de restos celulares e promovem a cicatrização e reorganização das áreas com inflamação. OBJETIVO: visto que alguns aspectos biológicos que permeiam a movimentação dentária ainda não estão totalmente esclarecidos, procurou-se, neste trabalho, verificar a expressão do INF-γ por células do periodonto de ratos submetidos à movimentação ortodôntica. MÉTODOS: a amostra foi constituída por nove ratos, cujos primeiros molares superiores direitos foram movimentados com uma força de 0,5N, por 3, 7 e 14 dias. Os molares esquerdos desempenharam o papel de grupo controle. RESULTADOS: através da imunohistoquímica, foi verificada a ausência de expressão de INF-γ na quase totalidade dos tecidos estudados,tanto no lado de pressão quanto no lado de tração.

INTRODUCTION: During the orthodontic treatment, an inflammatory process is induced, triggering series of biochemical events that results in dental movement. Stimuli such as hypoxia and mechanical deformation are the main factors responsible for the breaking of cell homeostasis, resulting in stress and liberation of several important mediators for tooth movement. To occur osseous remodeling during orthodontic treatments, regulating factors such as sub products of arachidonic acid and cytokines are released. To interferon-gamma (INF-γ ), a main cytokine released after induction of adaptive immune response, is attributed the function of attracting the macrophages, which aids in removing cell rests and promote healing and reorganization of the inflamed areas. AIM: Given that some biological aspects that permeate dental movement are not yet fully clear, we aimed in this study to investigate INF-γ expression in the periodontium of rats under orthodontic movement. METHODS: The sample was composed of 9 rats, whose first upper right molars were moved with a force of 0,5N, for 3, 7 and 14 days. The left molars were used as controls. RESULTS: Through immunohistochemistry, we verified the absence of INF-γ expression in almost all the studied tissues, in both the traction and pressure sides.

Existe correlação entre níveis séricos de anticorpos reativos a porphyromonas gingivalis e a condição periodontal clínica? / Is there any correlation between serum antibody levels reactive to porphyromonas gingivalis and clinical periodontal status?

Porphyromonasgingivalis has been shown to be shown to be one of the most important pathogen in chronic periodontitis development. The aim of this study was to evaluate the correlation among IgA, IgG and IgC and IgG isotype serum levels reactive Porphyromonas gingivalis ATTCC33277 and the clinical periodontal status. Twenty nine periodontitis patients were evaluated according to clinical parameters: probing depth, bleeding on probing, and clinical attachment loss measurements. Humoral immune response was assayed by enzyme linked immunosorbent assay (ELISA). There was no correlation between bleeding on probing (criterion 1) and the evaluated antibodies. Significant positive correlations were found between IgA levels and percentual of sites with clinical attachment loss (CAL) >3mm (criterion 2), percentual of sites with CAL > 5 mm (criterion 3), and percentual of sites with CAL > 3mm associated to probing depth > 4mm and bleeding on probing at the same site (criterion 4) (r=0,311; r=0,336; r=0,358, respectively; p<0,05). There were significant positive correlations between IgG serum levels and criteria 3 and 4 (r=0,400 and r=0,372, respectively; p<0,05), and between IgG1 and criteria 2, 3 and 4 (r=0,333, r=0,323 and r=0,340, respectively; p<0,05). The findings indicate that the antibody response to Porphyromonas gingivalis depends on the periodontal status, determined by clinical parameters

Diagnosis of canine brucellosis by ELISA using an antigen obtained from wild Brucella canis.

An indirect ELISA test was developed for the diagnosis of Brucella canis infection in dogs. A bacterial whole cell extract was used as a solid phase antigen, using B. canis isolated from an infected animal. Sera from culture-positive and healthy negative animals were used as internal reference controls. The cut-off point was determined by a mathematical formula for a statistically valid value, which defined the upper prediction limit, based on the upper tail of the t-distribution of 21 negative control sera readings, for the confidence level of 99.5%. The sensitivity and specificity of the ELISA test were 95% and 91%, respectively. The ELISA test showed a significant concordance index (K=0.84) with the agar gel immunodiffusion test. The reliability of the ELISA for the detection of infected animals was established by a double blind study testing 280 sera provided by serum banks from different diagnostic and research institutions and analyzed by ROC Curve.