Association of matrix metalloproteinase-1-1607 1G/2G single nucleotide polymorphism genotypes with periodontitis in Iraqi population / Associação entre genótipos de polimorfismo de nucleotídeo único de metaloproteinase-1-1607 1G/2G da matriz e periodontite em população iraquiana

Objective and background: Periodontitis is an inflammatory disease which is characterized by a progressive loss in the matrix of soft and hard tissue of periodontium particularly the collagen fibers which are cleaved by matrix Metalloproteinase (MMP). Indeed, increased activity of MMP mediates progression of periodontal diseases but population-based genetic variations could determine the susceptibility to the disease. The aim was to investigate association between MMP-1-1607 polymorphism with periodontitis among Iraqi individuals. Subjects and methods: The design of this study was a case-control for Iraqi individuals who were divided into two groups; periodontitis group (cases) and those with healthy periodontium (Control). For each subject, clinical periodontal parameters and demographic characteristics were recorded and venous blood was withdrawn for genetic analysis of MMP-1 by using PCR technique and DNA sequencing. Results: Analysis of MMP-1-1607 genotypes, by Hardy-Weinberg equilibrium, showed significant differences in the total sample. The most predominant MMP-1-1607 genotype among Controls was 1G/2G which was significantly different from periodontitis cohorts. Overall, 13 SNP were detected in periodontitis group versus 17 SNP in Control group. In addition, the periodontitis group showed a significant negative association between the probing pocket depth and MMP-1-1607. Conclusion: Results suggested that polymorphisms in MMP-1-1607 1G/2G may play a protective role and decreasing the susceptibility to periodontitis. (AU)

Introdução e objetivo: A periodontite é uma doença inflamatória caracterizada pela perda progressiva da matriz dos tecidos moles e duros do periodonto, particularmente as fibras de colágeno clivadas pelas metaloproteinases da matriz (MMPs). De fato, o aumento da atividade de MMPs medeia a progressão das doenças periodontais, mas as variações genéticas baseadas na população podem determinar a suscetibilidade à doença. O objetivo foi investigar a associação entre o polimorfismo MMP-1-1607 e periodontite em indivíduos iraquianos. População e método: O desenho deste estudo foi um caso-controle com indivíduos iraquianos, os quais foram divididos em dois grupos: grupo periodontite (casos) e indivíduos com periodonto saudável (controle). Para cada sujeito, os parâmetros clínicos periodontais e as características demográficas foram registrados, e o sangue venoso foi coletado para análise genética de MMP-1 por meio da técnica de PCR e sequenciamento de DNA. Resultados: A análise dos genótipos MMP-1-1607, pelo equilíbrio de Hardy-Weinberg, mostrou diferenças significativas na amostra total. O genótipo MMP-1-1607 mais predominante entre os controles foi 1G/2G, o qual foi significativamente diferente das coortes de periodontite. No geral, 13 SNP foram detectados no grupo periodontite versus 17 SNP no grupo controle. Além disso, o grupo periodontite mostrou uma associação negativa significativa entre a profundidade da bolsa de sondagem e MMP-1-1607. Conclusão: Os resultados sugerem que polimorfismos em MMP-1-1607 1G/2G podem desempenhar um papel protetor e diminuir a suscetibilidade à periodontite. (AU)

TNF-α levels and presence of SNP-308G/A of TNF-α gene in temporomandibular disorder patients

ABSTRACT Introduction: Temporomandibular disorder (TMD) refers to a group of conditions that compromise the harmonious movement and function of the temporomandibular joint, masticatory muscles, and associated structures. The etiopathogenesis of TMD is multifactorial but not well-understood, with the role of genetic factors still being unclear. Objective: This review aims to summarize the results of studies that evaluated TNF-α levels and the -308G/A TNF-α polymorphism in TMD patients. This study emphasizes the importance of a more selective treatment involving TNF-α inhibitors that can potentially reduce inflammation and pain, and improve quality of life. Methods: The MEDLINE/PubMed database, Cochrane Library, and Web of Science database were searched for case-control studies published until September 2020 that compared levels of TNF-α or presence of its -308G/A polymorphism in TMD patients and healthy individuals. Results: Six case-control studies were identified with a total of 398 TMD patients, aged between 12 and 78 years. The control group consisted of 149 subjects, aged between 18 and 47 years. The occurrence of TMD was predominant in females. Majority of studies found high TNF-α levels in TMD patients, compared to the control group. One of these studies found a positive correlation between the GA genotype and the development of TMD. Conclusion: Majority of the TMD patients showed elevated TNF-α levels, and a possible explanation for this could be the presence of the -308G/A polymorphism.

RESUMO Introdução: A disfunção temporomandibular (DTM) é definida como um grupo de alterações que comprometem a articulação temporomandibular, os músculos mastigatórios e as estruturas associadas. A etiopatogenia da DTM é multifatorial, e o papel dos fatores genéticos permanece obscuro. Objetivo: A presente revisão teve como objetivo descrever as contribuições de estudos que avaliaram os níveis de TNF-α e o polimorfismo -308 G/A em pacientes com DTM. Esse estudo enfatizou a importância de um tratamento mais completo envolvendo os inibidores do TNF-α que podem potencialmente reduzir a inflamação e a dor, contribuindo para melhorar a qualidade de vida do paciente. Métodos: As pesquisas foram realizadas nas bases de dados MEDLINE/PubMed, Cochrane Library e Web of Science, em busca de estudos de caso-controle publicados até setembro de 2020 que avaliassem os níveis de TNF-α e seu polimorfismo -308 G/A nos pacientes com DTM e em controles saudáveis. Resultados: Seis estudos de caso-controle foram identificados, com um total de 398 pacientes com DTM, e a idade variou de 12 a 78 anos. O grupo controle consistiu de 149 indivíduos e sua idade variou, aproximadamente, de 18 a 47 anos. O sexo feminino foi predominante. A maioria das pesquisas encontrou níveis elevados de TNF-α nos pacientes, em comparação com os controles. Um estudo encontrou uma associação positiva entre o genótipo GA e o desenvolvimento de DTM. Conclusão: A maioria dos pacientes com DTM demonstrou predisposição a uma maior produção de TNF-α, e isso poderia ser explicado pela presença do polimorfismo -308 G/A.

Polymorphisms of matrix metalloproteinase-7 and -9 are associated with oral tongue squamous cell carcinoma

Abstract Matrix degradation is an important event in the progression, invasion and metastasis of malignant head and neck lesions. Imbalances, mutations and polymorphisms of MMPs and their inhibitors are observed in several cancer subtypes. The aim of this study was to evaluate the association of the MMP-7 gene promoter (181 A/G) and MMP-9 (-1562 C/T) polymorphisms in oral tongue squamous cell carcinoma (OTSCC). MMP-7 (rs11568818) and MMP-9 (rs3918242) single-nucleotide polymorphisms (SNPs) were genotyped by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis in 71 cases of OTSCC. Normal tissue specimens were obtained from 60 healthy volunteers to serve as the control. The MMP-7 G allele and MMP-9 T allele were more frequent in the OTSCC group than the control group, but only when these two SNPs were taken together was a significant association found with the nodal metastasis of OTSCC (p < 0.001). Based on our results, SNPs in the promoter region of MMP-7 and MMP-9 appear to be associated with greater risk of developing OTSCC, and with a higher propensity to form metastatic tumors. In this respect, molecular studies investigating polymorphisms may be useful in predicting tumor behavior.

Analysis of porphyromonas gingivalis fimA genotypes in severe periodontitis patients

Abstract The aim of this study was to i) evaluate the prevalence of P. gingivalis and the genotypes fim A I, Ib, II, III, IV, and V in Brazilian patients with periodontitis stage III and IV, grades B and C, ii) compare periodontitis grades B and C with regard to the prevalence of P. gingivalis and fim A genotypes, and iii) correlate the presence of these pathogens with clinical periodontal variables. Two samples of subgingival biofilm were collected from the interproximal sites with the greatest clinical attachment loss (CAL) of each patient (grade B = 38; grade C = 54) and submitted to polymerase chain reaction (PCR) for the identification of P. gingivalis and fim A genotypes. The collected periodontal clinical parameters included gingival index, plaque index, probing depth (PD), bleeding on probing (BoP) and CAL. P. gingivalis was present in 61.96% of the samples, but more prevalent in patients with grade C periodontitis (p = 0.048) and higher CAL (p < 0.001), PD (p < 0.001), and BoP (p = 0.01) values, and at sites with high CAL values (p = 0.01). The fim A II genotype was more prevalent in patients with greater mean PD (p = 0.04) and a higher proportion of bleeding sites (p = 0.006). Thus, in this sample of Brazilian periodontitis patients, the presence of P. gingivalis was associated with grade C periodontitis and periodontal destruction, while the fim A II genotype was associated with increased PD and BoP, supporting the notion that P. gingivalis fim A II is an important virulence factor in periodontal tissues.

miR-9-1 gene methylation and DNMT3B (rs2424913) polymorphism may contribute to periodontitis

Abstract Genetic and epigenetic changes have been associated with periodontitis in various genes; however, little is known about genes involved in epigenetic mechanisms and in oxidative stress. Objective: This study aims to investigate the association of polymorphisms C677T in MTHFR (rs1801133) and −149C→T in DNMT3B (rs2424913), as well as the methylation profiles of MTHFR, miR-9-1, miR-9-3, SOD1, and CAT with periodontitis. The association between polymorphisms and DNA methylation profiles was also analyzed. Methodology: The population studied was composed of 100 nonsmokers of both sexes, divided into healthy and periodontitis groups. Genomic DNA was extracted from the epithelial buccal cells, which were collected through a mouthwash. Polymorphism analysis was performed through polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP), while methylation-specific PCR (MSP) or combined bisulfite restriction analysis techniques were applied for methylation analysis. Results: For DNMT3B, the T allele and the TT genotype were detected more frequently in the periodontitis group, as well as the methylated profile on the miR-9-1 promoter region. There was also a tendency towards promoter region methylation on the CAT sequence of individuals with periodontal disease. Conclusion: The polymorphism −149C→T in DNMT3B (rs2424913) and the methylated profile of the miR-9-1 promoter region are associated with periodontitis.

Frequency of Porphyromonas gingivalis fimA in smokers and nonsmokers after periodontal therapy

Abstract Porphyromonas gingivalis is one of the most important Gram-negative anaerobe bacteria involved in the pathogenesis of periodontitis. P. gingivalis has an arsenal of specialized virulence factors that contribute to its pathogenicity. Among them, fimbriae play a role in the initial attachment and organization of biofilms. Different genotypes of fimA have been related to length of fimbriae and pathogenicity of the bacterium. Objectives The aim of this study was to identify 5 types of fimA genotype strains in smokers and nonsmokers with periodontitis, before and after periodontal therapy. Material and Methods Thirty-one patients with periodontitis harboring P. gingivalis were selected: 16 nonsmokers (NS) and 15 smokers (SM). Clinical and microbiological parameters were evaluated at baseline and 3 months after periodontal treatment, namely: plaque index, bleeding on probe, probing depth, gingival recession and clinical attachment level. The frequency of P. gingivalis and fimA genotype strains were determined by polymerase chain reaction. Results Type I fimA was detected in the majority of SM and NS at baseline, and the frequency did not diminish after 3 months of treatment. The frequency of type II genotype was higher in SM than NS at baseline. After 3 months, statistical reduction was observed only for types II and V fimA genotypes in SM. The highest association was found between types I and II at baseline for NS (37.5%) and SM (53.3%). Conclusion The most prevalent P. gingivalis fimA genotypes detected in periodontal and smoker patients were genotypes I and II. However, the presence of fimA genotype II was higher in SM. Periodontal treatment was effective in controlling periodontal disease and reducing type II and V P. gingivalis fimA.

Genes candidatos às anomalias dentárias em pacientes portadores de maloclusão esquelética / Candidate genes for dental anomalies in patients skeletal malocclusion

O objetivo do presente estudo foi verificar a presença de associação fenótipo-genotípico entre TGFA (Fator de Crescimento Transformante α) (C/T rs1523305), IRF6 (Fator Regulatório Interferon 6) (A/C rs2013162) e MSX1 (Segmento Muscular Homeobox 1) (A/G rs12532) e anomalias dentárias em pacientes com malclusão esquelética. Para tanto, dois estudos prévios foram realizados com os objetivos de (I) determinar se indivíduos com discrepâncias esqueléticas de Classe II ou III apresentam uma maior frequência de anomalias dentárias em comparação com indivíduos com maloclusão de Classe I e (II) comparar quatro diferentes métodos de coleta salivar e de células bucais [Expectoração da Saliva (1), Expectoração da Saliva com Estímulo Lingual (2), Raspagem com Escova Citológica (3) e Raspagem com Escova Citológica mais Expectoração da Saliva (4)] para extração de DNA genômico, avaliando sua concentração e pureza. Na revisão sistemática, foi realizada uma busca nas principais bases de dados da literatura científica médica eletrônica. Estudos observacionais foram selecionados se fossem mencionadas anomalias dentárias nos diferentes padrões de maloclusão esquelética. Foi adotado um conjunto de critérios para elegibilidade do estudo, com base na estratégia PECOS (População: maxila e mandíbula; Exposição: discrepâncias esqueléticas; Comparação: padrão de normalidade; e Resultado: anomalias dentárias). Cinco estudos retrospectivos contendo 7679 participantes foram classificados e considerados elegíveis para a revisão sistemática. A amostra do estudo II foi composta por 20 participantes. As coletas foram realizadas com intervalo de no mínimo um dia entre elas e foram armazenadas a -20°C até a extração do DNA ser realizada (Qiagen®). O estudo III foi composto por uma amostra de 505 registros ortodônticos. Dezenove pontos cefalométricos, serviram para a obtenção dos ângulos e medidas utilizados para a caracterização esquelética, utilizando-se o Software Dolphin. Amostras de saliva foram coletadas de todos os participantes e o DNA foi extraído, diluído e quantificado. Os genes TGFA, IRF6 e MSX1 foram usados para reações de PCR em tempo real. Os testes Razão de chance, Qui-quadrado, Exato de Fisher, T independente e coeficiente de correlação (nível de significância = 95%) foram realizados. A partir da revisão sistemática, concluiu-se que indivíduos com padrões de maloclusão esquelética têm mais anomalias dentárias. Após a análise estatística, não foi observado dimorfismo sexual em relação à concentração de DNA (p = 0,76), idade (p = 0,91) e etnias (p = 0,72). Não houve diferença significativa entre os métodos de coleta em relação à quantidade e pureza do DNA extraído (p≥0,05). O gene IRF6 foi associado com a ME Classe III (p = 0,04, OR = 0,69, IC 0,49-0,98) e o gene MSX1 foi associado ao padrão de crescimento hipodivergente (p=0,003, OR=0,5, IC 0,36-0,74) e ME Classe II (p=0,0001, OR=0,6, IC 0,46-0,78). Em relação a AD, o gene MSX1 também foi associado à impactação (p=0,03, OR=0,67, IC 0,47-0,96) e dilaceração (p=0,04, OR=0,27, IC 0,07-0,977). MSX1 associouse ao padrão de crescimento hipodivergente e Classe II, e impactação e dilaceração, mostrando que existe uma associação genética entre anomalias dentárias e maloclusões esqueléticas. (AU)

The objective of the present study was to verify the phenotype-genotype association between TGFA (Transforming Growth Factor α) (C/T rs1523305), IRF6 (Interferon Regulatory Factor 6) (A/C rs2013162) and MSX1 (Muscle Segment Homeobox 1) (A/G rs12532) and dental anomalies in patients with skeletal malocclusion. Two previous studies were carried out with the objective of (I) to determine if individuals with Class II or III skeletal discrepancies present a higher frequency of dental anomalies compared to individuals with Class I malocclusion and (II) to compare four different types of saliva and oral buccal cell collecting methods for genomic DNA extraction: (1)Expectoration of saliva, (2)Expectoration of saliva with lingual stimulation, (3)Scraping with cytological brush, and (4)Scraping with cytological brush and expectoration of saliva, evaluating its concentration and purity. In the systematic review, a search of the main electronic medical scientific literature databases was conducted. Observational studies were selected if mentioning dental anomalies in the different skeletal malocclusion patterns. A set of criteria for the eligibility of the study was adopted, based on the PECOS strategy (Population: maxilla and mandible, Exposure: skeletal discrepancies, Comparison: normality pattern, and Outcome: dental anomalies). Five retrospective studies containing 7679 participants were classified and considered eligible for the systematic review. The sample of study II was composed by 20 participants. The biological samples were collected at intervals of at least one day between them and were stored at -20 ° C until DNA extraction was performed (Qiagen®). Study III was composed of a sample of 505 orthodontic records. Nineteen cephalometric points were used to obtain the angles and measurements used for the skeletal characterization, using Dolphin Software. Saliva samples were collected from all participants and the DNA was extracted, diluted and quantified. The TGFA, IRF6 and MSX1 genes were used for real-time PCR reactions. The odds ratio, chi-square, Fisher's exact, independent T and correlation coefficient (significance level = 95%) tests were performed. From the systematic review, it was concluded that individuals with skeletal malocclusion patterns have more dental anomalies. After the statistical analysis, no sexual dimorphism (p = 0.76), age (p = 0.91) and ethnicity (p = 0.72) was observed in relation to DNA concentration. There was no significant difference between the collection methods in relation to the amount and purity of the extracted DNA (p≥0.05). IRF6 was associated with Class III skeletal malocclusion (p=0.04, OR=0.69, C.I. 0.49-0.98), and MSX1 was associated with hypodivergent growth pattern (p=0.003, OR=0.5, 95% C.I. 0.36-0.74), and Class II skeletal malocclusion (p=0.0001, OR=0.6, C.I. 0.46-0.78). In regards to dental anomalies, MSX1 was also associated with tooth impaction (p=0.03, OR=0.67, 95% C.I. 0.47-0.96) and root dilaceration (p=0.04, OR=0.27, 95% C.I. 0.07-0.97). MSX1 was associated with both hypodivergent growth pattern and Class II skeletal malocclusion (p=0.0001), and tooth impaction (p=0.03) and root dilaceration (p=0.04), whereas IRF6 was associated with Class III skeletal malocclusion, (AU)

El objetivo del presente estudio fue verificar la presencia de asociación fenotipo-genotípica entre TGFA (Factor de crecimiento transformante α) (C / T rs1523305), IRF6 (Factor regulador de interferón 6) (A / C rs2013162) y MSX1 (Segmento muscular 1 de Homeobox 1). ) (A / G rs12532) y anomalías dentales en pacientes con malclusión esquelética. Con este fin, se realizaron dos estudios previos para (I) determinar si las personas con discrepancias esqueléticas de Clase II o III tienen una mayor frecuencia de anomalías dentales en comparación con las personas con maloclusión de Clase I y (II) para comparar cuatro métodos diferentes. y colección de células salivales [Esputo de saliva (1), Estímulo lingual Saliva Esputo (2), Raspado con cepillo citológico (3) y Raspado con cepillo citológico más Esputo de saliva (4)] para extracción de ADN genómico , evaluando su concentración y pureza. En la revisión sistemática, buscamos en las principales bases de datos de la literatura científica médica electrónica. Se seleccionaron estudios de observación si se mencionaban anomalías dentales en los diferentes patrones de maloclusión esquelética. Se adoptó un conjunto de criterios para la elegibilidad del estudio, basado en la estrategia PECOS (Población: maxilar y mandíbula; Exposición: discrepancias esqueléticas; Comparación: patrón de normalidad; y Resultado: anomalías dentales). Cinco estudios retrospectivos con 7679 participantes fueron clasificados y considerados elegibles para una revisión sistemática. La muestra del estudio II consistió en 20 participantes. Se tomaron muestras con al menos un día de diferencia y se almacenaron a -20 ° C hasta que se realizó la extracción de ADN (Qiagen®). El estudio III consistió en una muestra de 505 registros de ortodoncia. Diecinueve puntos cefalométricos se utilizaron para obtener los ángulos y las medidas utilizadas para la caracterización esquelética utilizando Dolphin Software. Se recogieron muestras de saliva de todos los participantes y se extrajo, diluyó y cuantificó el ADN. Los genes TGFA, IRF6 y MSX1 se usaron para reacciones de PCR en tiempo real. Se realizaron las pruebas de odds ratio, Chi-cuadrado, exacta de Fisher, T independiente y coeficiente de correlación (nivel de significancia = 95%). De la revisión sistemática, se concluyó que las personas con patrones de maloclusión esquelética tienen más anomalías dentales. Después del análisis estadístico, no se observó dimorfismo sexual en relación con la concentración de ADN (p = 0,76), la edad (p = 0,91) y el origen étnico (p = 0,72). No hubo diferencias significativas entre los métodos de recolección con respecto a la cantidad y pureza del ADN extraído (p≥0.05). El gen IRF6 se asoció con ME Clase III (p = 0.04, OR = 0.69, CI 0.49-0.98) y el gen MSX1 se asoció con el patrón de crecimiento hipodivergente (p = 0.003, OR = 0.5, CI 0.36-0.74) y EM Clase II (p = 0.0001, OR = 0.6, CI 0.46-0.78). Con respecto a AD, el gen MSX1 también se asoció con impactación (p = 0.03, OR = 0.67, CI 0.47-0.96) y laceración (p = 0.04, OR = 0.27, IC 0,07-0,977). MSX1 se asoció con un patrón de crecimiento hipodivergente y de Clase II, impactación y laceración, lo que demuestra que existe una asociación genética entre las anomalías dentales y las maloclusiones esqueléticas. (AU)

Análise da associação entre a periodontite e polimorfismos de nucleotídeo único da interleucina-1beta / Analysis of the association between periodontitis and interleukin-1beta single nucleotide polymorphisms

A periodontite é uma doença inflamatória, que pode ser classificada em Periodontite Crônica (PC) ou Periodontite Agressiva (PA), desencadeada por um desequilíbrio na microbiota subgengival, que pode ser influenciado por diversos fatores, como polimorfismos genéticos. Dessa forma, o objetivo deste trabalho foi analisar, através de uma revisão da literatura, se há ou não associação entre a periodontite e polimorfismos genéticos de nucleotídeo único (SNPs). Os genes IL1B +3954(3), -511, -31 foram os alvos desta pesquisa, por serem os mais estudados e apresentarem boa plausibilidade biológica. Foi realizada uma busca no PubMed e ao final 24 artigos de estudos casos-controle foram selecionados. Na maioria dos estudos não foi encontrada associação positiva entre os SNPs +3954(3), -511, -31 da IL1B e a PA ou PC. Dessa forma, é possível concluir que não há associação positiva entre a periodontite e os SNPs IL1B +3954(3), -511, -31 e PA e PC. Todavia os resultados devem ser analisados com cautela, pois os estudos apresentam limitações. (AU)

Periodontitis is an inflammatory disease which is classified as chronic periodontitis (PC) or aggressive periodontitis (PA) and is initiated by an unbalance in subgengival microbiota which for their part can be influenced by a lot of factors, such as genetic polymorphism. Therefore, the aim of this study was to analyse if there is an association between periodontitis and single nucleotide polymorphisms (SNPs). The genes IL1B +3954(3), -511, -31 were chosen as the targets of this literature review, because they have good biologic plausibility and are the most studied in literature. A search was conducted on PubMed and the results analysed and 24 case-controls articles were chosen.Most of the studies did not find a positive association between the ILB1 SNPs +3954(3), -511, -31 and PA e PC. Therefore, the case-controls studies indicated that there is no positive association between SNPs IL1B +3954(3), -511, -31 and PA or PC. However, the results of this work must be analysed carefully as the studies used have limitations. (AU)

Association of single nucleotide polymorphisms in AXIN2, BMP4, and IRF6 with Non-Syndromic Cleft Lip with or without Cleft Palate in a sample of the southeast Iranian population

Abstract Non-syndromic cleft lip with or without palate (NSCL/P) is a common congenital malformation worldwide, with complex etiology. It has been proposed that interaction of genes and environmental factors play a role in the predisposition to this disease. Objectives: The aim of this study was to examine the association between AXIN2 (axis inhibition protein 2) rs7224837, BMP4 (bone morphogenetic protein 4) rs17563, and IRF6 (interferon regulatory factor 6) rs861019 and 2235371 polymorphisms and NSCL/P in an Iranian population. Material and Methods: This case-control study was carried out on 132 unrelated NSCL/P patients and 156 healthy subjects. The variants were genotyped using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Results: The findings suggest that BMP4 rs17563 polymorphism significantly decreased the risk of NSCL/P in codominant (OR=0.36, 95%CI=0.17-0.79, p=0.012, CT vs CC and OR=0.11, 95%CI=0.01-0.88, p = 0.019, TT vs CC), dominant (OR=0.30, 95%CI=0.15-0.62, p = 0.0007, CT+TT vs CC), recessive (OR=0.12, 95%CI=0.02-0.99, p = 0.023, TT vs CC+CT), overdominant (OR=0.39, 95%CI = 0.18-0.84, p=0.021, CT vs CC+TT), and allele (OR=0.28, 95%CI=0.15-0.55, p<0.0001, T vs C) inheritance models. Our findings did not support an association between AXIN2 rs7224837 and IRF6 rs861019 polymorphism and risk/protection of NSCL/P. The IRF6 2235371 variant was not polymorphic in our population. Conclusion: The results indicate that the BMP4 rs17563 variant is likely to confer a protective effect against the occurrence of NSCL/P in a sample of the southeast Iranian population.

Association of genetic polymorphisms with resistance and susceptibility phenotypes to chronic inflammatory osteolytic periapical and periodontal lesions / Associação de polimorfismos genéticos com os fenótipos de resistência e susceptibilidade à lesões osteolíticas periodontais e periapicais

Chronic periodontitis and apical periodontitis are infectious diseases characterized by the inflammatory destruction of teeth-supporting tissues. The clinical presentation of these diseases is the result of the interaction between the infecting microorganisms and the host's defense mechanisms, constituting the host/pathogen barrier. Genetic variations are associated with differential susceptibility profiles, modulating simultaneously the patterns of infection and immune response. Therefore, we investigated the association of selected genetic variations with phenotypes of resistance or susceptibility to periodontal and periapical inflammatory bone resorption, as well as with changes in the sub gingival microbial profile and host's response biomarkers. The polymorphism rs4794067 (gene TBX21) proved significantly associated with increased risk to suffer periodontitis. Polymorphic allele-carriers demonstrated increased expression of T-bet. IFN-γ expression and bacterial load proved unaltered by genotype differences. The mutation rs333 (a.k.a. CCR5Δ32, in gene CCR5) demonstrated a protective effect against chronic periodontitis. Heterozygous subjects exhibited decreased TNF-α expression. The genetic mutation was unrelated to changes in the bacterial load of putative periodontal pathogens. The polymorphisms rs2521634 (gene NPY), rs10010758 (gene TBC1D), rs6667202 (gene IL10), and rs10043775 (gene TBXO38) proved associated with significant changes in the composition of the subgingival biofilm in chronic periodontitis patients. For apical periodontitis we employed an unbiased biomarker screening strategy based in 2D diferential electrophoresis in tandem with mass spectrometry. Among the biomarkers that proved significantly modulated, we discover a substantial upregulation of HSP27 and SERPINB1. Both proteins were preferentially localized in the cytoplasm of epithelial cells in the epithelium lining the cystic cavity and the epithelial chords of epithelized granulomas. Additionally, SERPINB1 was expressed in infiltrating polymorph nuclear neutrophils. The expression of HSP27 and SERPINB1 demonstrated a negative correlation with acute inflammation biomarkers. Overall, these genes and protein biomarkers may be promissory targets to predict the risk profile for periodontal and periapical inflammatory bone resorption.(AU)

A periodontite crônica e a periodontite apical são doenças infecciosas caraterizadas pela destruição inflamatória dos tecidos de suporte dentários. O fenótipo clínico de ambas as doenças é o resultado da interação entre os microrganismos infectantes e os mecanismos de defesa do hospedeiro (barreira hospedeiro/patógeno). Ainda, variações genéticas podem conferir níveis diferenciais de susceptibilidade a tais doenças, teoricamente modulando tanto os padrões de infecção como de resposta do hospedeiro. Neste contexto, investigamos a associação de variações genéticas selecionadas com fenótipos de resistência e susceptibilidade a lesões osteolíticas periodontais e periapicais, assim como possíveis associações com mudanças no perfil microbiológico sub gengival e em marcadores de resposta do hospedeiro. O polimorfismo rs4794067 (no gene TBX21) demonstrou uma associação significativa com risco aumentado de sofrer periodontite crônica. Os portadores do alelo polimórfico apresentaram uma expressão significativamente aumentada de Tbet. No entanto, a expressão de IFN-γ e a carga bacteriana mostraram-se independentes do perfil genético para rs4794067. O polimorfismo rs333 (também conhecido como CCR5Δ32, no gene CCR5) demonstrou um efeito protetor para periodontite crônica. Os pacientes heterozigotos exibiram níveis de expressão significativamente diminuídos de TNF-α, porém, os níveis bacterianos mostraram-se independentes do perfil genético para rs333. Os polimorfismos rs2521634 (no gene NPY), rs10010758 (no gene TBC1D), rs6667202 (no gene IL10) e rs10043775 (no gene TBXO38) demostraram uma associação significativa com mudanças no perfil microbiológico sub gengival em pacientes com periodontite crônica. No caso da periodontite apical, escolhemos uma metodologia de seleção de marcadores baseada no uso consecutivo de eletroforeses diferencial bidimensional e espectrometria de massa. Dentre os marcadores que apresentaram uma modulação significativa, as lesões de periodontite apical demostraram uma supraregulação de HSP27 e SERPINB1. Ambas as proteínas foram preferencialmente imunomarcadas nas ilhas epiteliais dentro das lesões. A expressão de HSP27 e SERPINB1 apresentou uma correlação negativa com os marcadores de inflamação aguda. Assim sendo, estes genes e biomarcadores proteicos mostram-se como alvos promissórios para a determinação do perfil de risco de lesões osteolíticas periodontais e periapicais.(AU)

MMP1-1607 polymorphism increases the risk for periapical lesion development through the upregulation MMP-1 expression in association with pro-inflammatory milieu elements

ABSTRACT Increased matrix metalloproteinases (MMPs) activity is a hallmark of periapical granulomas. However, the factors underlying the MMPs expression modulation in healthy and diseased periapical tissues remains to be determined. Objective In this study, we evaluated the association between the MMP1-1607 polymorphism (rs1799750) and pro-inflammatory milieu elements with MMP-1 mRNA levels in vivo. Material and Methods MMP1-1607 SNP and the mRNA levels of MMP-1, TNF-a, IFN-g, IL-17A, IL-21, IL-10, IL-4, IL-9, and FOXp3 were determined via RealTimePCR in DNA/RNA samples from patients presenting periapical granulomas (N=111, for both genotyping and expression analysis) and control subjects (N=214 for genotyping and N=26 for expression analysis). The Shapiro-Wilk, Fisher, Pearson, Chi-square ordinal least squares regression tests were used for data analysis (p<0.05 was considered statistically significant). Results The MMP1-1607 1G/2G and 1G/2G+2G/2G genotypes were significantly more prevalent in the patients than in controls, comprising a risk factor for periapical lesions development. MMP-1 mRNA levels were higher in periapical lesions than in healthy periodontal ligament samples, as well as higher in active than in inactive lesions. The polymorphic allele 2G carriers presented a significantly higher MMP-1 mRNA expression when compared with the 1G/1G genotype group. The ordered logistic regression demonstrated a significant correlation between the genetic polymorphism and the expression levels of MMP-1. Additionally, the pro- and anti-inflammatory cytokines IL-17A, IFN-g, TNF-a, IL-21, IL-10, IL-9, and IL-4 were significant as complementary explanatory variables of MMP-1 expression. Conclusion The MMP1-1607 SNP was identified as a risk factor for periapical lesions development, possibly due to its association with increased MMP-1 mRNA levels in periapical lesions. The MMP-1 expression is also under the control of the inflammatory milieu elements, being the cytokines TNF-a, IL-21, IL-17A, and IFN-g associated with increased MMP-1 levels in periapical lesions, while IL-10, IL-9, or IL-4 presented an inverse association.

The functional EGF+61 polymorphism and nonsyndromic oral clefts susceptibility in a Brazilian population

AbstractNonsyndromic oral clefts are considered a problem of public health in Brazil, presenting a multifactorial etiology that involves genetic and environmental components, such as maternal alcohol consumption. Several candidate genes have been investigated to identify some association with nonsyndromic clefts risk. The epidermal growth factor (EGF) gene is implicated in the normal craniofacial development and its functional +61 A>G polymorphism has been related to cancer susceptibility. It has been suggested that cancer and oral clefts may share the same molecular pathways.Objective Our goal was to evaluate the association between the EGF+61 A>G polymorphism and nonsyndromic oral clefts susceptibility.Material and Methods The case-control study included 218 cleft cases and 253 controls from Brazil. The control group was comprised of individuals without congenital malformations, dental anomalies and family history of clefts. The cleft phenotypes and subphenotypes were determined based on clinical examination. Genomic DNA was extracted from oral mucosa cells obtained by mouthwash. The EGF+61 A>G polymorphism genotype was determined by polymerase chain reaction-restriction fragment length polymorphism.Results We noticed the association between maternal alcohol consumption during pregnancy and cleft occurrence. The A allele and AA genotype were over-represented in cleft cases compared with control group when we considered the bilateral cleft lip with or without cleft palate (CL±P) cases, cleft cases with tooth agenesis and cleft cases presenting family history of cleft, but the differences were not statistically significant. Contradictorily, the G allele was higher in cleft palate only (CP) cases than in control group, showing a borderline p value. Comparing the different cleft phenotypes, we observed statistical differences between CP and CL±P cases. Our data suggest the EGF+61 A>G polymorphism was not related with nonsyndromic oral clefts susceptibility in a Brazilian population, but supported the different genetic background between CL±P and CP. Moreover, we confirmed the potential effect of maternal alcohol intake on cleft risk in our population.

Triagem de mutações e polimorfismos de genes candidatos à malformação dentária em pacientes com fissura labiopalatinas / Screening of mutations and polymorphisms of candidate genes to dental malformation in patients with cleft lip and palate

O propósito deste trabalho foi investigar a ocorrência de mutações e polimorfismos em genes candidatos aos defeitos na formação do esmalte dentário em indivíduos com fissura labiopalatina (FLP) transforame incisivo unilateral ou bilateral isolada e associar o genótipo-fenótipo dos indivíduos com FLP e malformação dentária (MD) nos dentes incisivos centrais superiores permanentes. Foram coletadas amostras de saliva de 165 indivíduos de 6 a 15 anos de idade, de ambos os sexos, divididos em 4 grupos de estudo: Grupo 1 - 46 indivíduos com FLP e MD; Grupo 2 - 34 indivíduos com FLP e sem MD; Grupo 3 - 34 indivíduos sem FLP e com MD; Grupo 4 - 51 indivíduos sem FLP e MD. Foi realizada a extração do DNA genômico das amostras de saliva, seguida da Reação em Cadeia da Polimerase, sequenciamento direto dos éxons 2, 3, 4, 5, 6 e 7 do gene AMELX e genotipagem dos SNPs rs3796703, rs3796704, rs3796705, rs7671281, rs2609428 e rs35951442 no gene ENAM. Para a análise estatística dos resultados foi utilizado o Teste Exato de Fisher e o Teste do Qui-quadrado de Pearson. Em relação ao sequenciamento direto do gene AMELX, mutações foram encontradas em 30,4% (n=14), 35,3% (n=12), 11,8% (n=4) e 13,7% (n=7) dos indivíduos dos Grupos 1, 2, 3 e 4, respectivamente. Trinta e sete mutações foram detectadas e distribuídas ao longo dos éxons 2 (1 mutação - 2,7%), 6 (30 mutações - 81,08%) e 7 (6 mutações - 16,22%) do gene AMELX. Houve um aumento significativo (p=0,003) na frequência de mutações nos indivíduos com FLP (Grupos 1 e 2 - 65,7%) em relação aos indivíduos sem FLP (Grupos 3 e 4 - 25,5%). Em relação às 30 mutações encontradas no éxon 6, 43,34% (n=13), 23,33% (n=7), 13,33% (n=4) e 20% (n=6) foram encontrados nos Grupos 1, 2, 3 e 4, respectivamente. A mutação silenciosa c.261C>T (rs2106416) foi detectada em 26 indivíduos distribuídos nos quatro grupos estudados, sendo significativamente mais encontrada (p=0,003) nos grupos com FLP (23,75%), em comparação com os...

The purpose of this study was to investigate the occurrence of mutations and polymorphisms (SNPs) in candidate genes to defects in the formation of enamel in individuals with cleft lip and palate (CLP) unilateral or bilateral incisive transforame isolated and associate genotype-phenotype of individuals with CLP and dental malformation (DM) in permanent teeth maxillary central incisors. For analysis of the proposed genes, saliva samples from 165 individuals from 6 to 15 years old, of both genders, were collected and divided into 4 groups: Group 1 - 46 individuals with CLP and DM; Group 2 - 34 individuals with CLP and without DM; Group 3 - 34 subjects without CLP and DM; Group 4 - 51 subjects without CLP and DM. Extraction of genomic DNA from saliva samples was performed, followed by Polymerase Chain Reaction, direct sequencing of 2, 3, 4, 5, 6 and 7 exons of AMELX gene and genotyping of SNPs rs3796703, rs3796704, rs3796705, rs7671281, rs2609428 and rs35951442 in the ENAM gene. For statistical analysis we used the Fisher's exact test and Pearson's chi-square test. Regarding direct sequencing of AMELX gene, mutations were found in 30.4% (n=14), 35.3% (n=12), 11.8% (n=4) and 13.7% (n=7) of individuals in Groups 1, 2, 3 and 4, respectively. Thirty-seven mutations were detected and distributed over the exons 2 (1 mutation - 2.7%), 6 (30 mutations - 81.08%) and 7 (6 mutations - 16.22%) of AMELX gene. There was a significant increase (p=0.003) in the frequency of mutations in individuals with CLP (Groups 1 and 2 - 65.7%) compared to subjects without CLP (Groups 3 and 4 - 25.5%). Regarding the 30 mutations found in exon 6, 43.34% (n=13), 23.33% (n=7), 13.33% (n=4) and 20% (n=6) were found in Groups 1, 2, 3 and 4, respectively. The c.261C>T silent mutation (rs2106416) was detected in 26 individuals distributed in all groups studied, and was significantly more found (p=0.003) in the groups with CLP (23.75%) compared to the groups without CLP (8.23%). In groups without...

Efeito da redução do aporte nutricional na diversidade genotípica e nos fatores de virulência de bactérias cariogênicas isoladas de dentina cariada selada / Stress starvation effect on the genotypic diversity and virulence factors of cariogenic bacteria isolated from sealed carious dentin

No tratamento de lesões profundas de cárie, a Remoção Parcial de Dentina Cariada (RPDC) e restauração tem sido proposta como alternativa conservadora para evitar perda de tecido dentário e exposição pulpar. Existe uma hipótese de que uma seleção de bactérias ocorre abaixo de restaurações devido a um acesso limitado de nutrientes. No entanto, há falta de conhecimento sobre a diversidade e potencial de virulência das bactérias cariogênicas residuais seladas abaixo de restaurações sobre dentina cariada. O objetivo deste estudo foi caracterizar Streptococcus mutans e lactobacilos isolados de dentina cariada antes e após o estresse nutricional por selamento da cavidade. S. mutans e lactobacilos foram obtidos por cultivo da dentina cariada de lesões cavitadas de quatro e seis pacientes, respectivamente. Duas amostras de dentina cariada foram coletadas e cultivadas por paciente: uma antes e outra após três meses de selamento da cavidade. Colônias de S. mutans e lactobacilos preditos foram selecionadas, isoladas e analisadas por coloração de Gram. Genes “housekeeping” foram utilizados na identificação da espécie (gtfB para S. mutans e pheS/rpoA/groEL/16SrRNA para lactobacilos) e a técnica de AP-PCR foi utilizada para genotipagem. A análise fenotípica (produção de ácido e de tolerância ao ácido) foi realizada. Um total de 48 isolados representativos de S. mutans foram analisados (31 antes e 17 após estresse nutricional por meio do selamento). O número de genótipos diferentes de S. mutans encontrado foi de nove e seis antes e após selamento, respectivamente. Pelo menos um dos genótipos encontrados antes do selamento foi também encontrado na dentina após o estresse nutricional por meio do selamento...

A hypothesis exists that a selection of bacteria occurs underneath restoration due to a limited access of nutrients. However, there is a lack of evidence regarding their role in the progression of carious process beneath restorations after Partial Dentin Caries Removal. It still unclear if the diversity and the virulence potential of the sealed bacteria remain the same after sealing. The aim of this study was to characterize Streptococcus mutans and Lactobacillus species isolated from caries dentin before and after starvation stress by cavity sealing. S. mutans and lactobacilli were obtained by culture of carious dentin from four and six patients, respectively. Two carious dentin samples were collected and cultured per patient: 1st before and 2nd after three months of cavity sealing. Presumptive S. mutans and lactobacilli were selected, isolated and analyzed by Gram staining. Housekeeping genes sequencing were used to the species identification (gtfB for S. mutans and pheS/rpoA/groEL/16SrRNA for lactobacilli) and Arbitrary Primer-PCR (AP-PCR) was used for genotyping. Phenotypic analysis (acid production and acid tolerance) was performed. A total of 48 representative S. mutans isolates were genotyped (31 before and 17 after the sealing). The number of different genotypes identified was nine and six before and after sealing, respectively. At least one of the genotypes found before the sealing was also found on dentin after the sealing in all patients. Regarding lactobacilli, it was analyzed 86 strains, 41 before and 45 after starvation stress by sealing. L. paracasei and L. rhamnosus prevailed and only four isolates did not belong to these species. A total of 27 and 15 different genotypes were found before and after sealing, respectively...

Valor prognóstico dos polimorfismos fincionais nos genes da mmp-1, mmp-13 e il-8 no carcinoma epidermóide oral e de orofaringe / Fincionais prognostic value of polymorphisms in the genes of MMP-1, MMP-13 and IL-8 in oral squamous cell carcinoma and oropharyngeal

Tumores malignos têm a habilidade de invadir tecidos normais e de se espalharem para sítios anatômicos distantes, originando a metástase, o maior fator de mortalidade do câncer. As metaloproteinases de matriz (MMP)-l e MMP-13 têm sido associadas à invasão tumoral e à metástase, pois a MMP-1 degrada colágeno tipo I, que é o substrato mais abundante no estroma tumoral e a MMP-13 degrada colágeno tipo IV, dentre outros, que está presente na membrana basal dos vasos. Pesquisas mostram que a IL-8 é um potente fator angiogênico e está associada ao crescimento tumoral, à metástase e ao pobre prognóstico do câncer. O presente trabalho se propõe a verificar a existência e a frequência dos polimorfismos nos genes das MMPs-1 (rs2071230 e rs470558), -13 (rs2252070) e da IL-8 (rs4073 e rs2227532) e investigar o possível valor prognóstico dos mesmos em uma série de casos de carcinoma epidermóide oral e de orofaringe (CEOO). Foram genotipados por meio de PCR em tempo real 98 amostras de pacientes com carcinoma epidermóide e 134 amostras controle. Todos os polimorfismos estavam em equilíbrio de Hardy-Weinberg, exceto o SNP IL-8 (rs2227532). O genótipo homozigoto polimórfico GG da MMP-1 (rs2071230) revelou ser um fator de risco pouco mais de 8 vezes para o desenvolvimento do carcinoma epidermóide, enquanto o genótipo polimórfico GG da MMP-13 (rs2252070) diminuiu o risco de desenvolver CEOO em aproximado de 3 vezes. Verificou-se diferença na distribuição dos genótipos em relação à localização da lesão, sendo o genótipo CC da MMP-1 (rs470558) mais frequente em lesões intraorais e o CT em orofaringe e o genótipo TT da IL-8 (rs4073) mais comum em lesões intraorais e com estadiamento clínico III e IV. Os indivíduos portadores do genótipo GG da MMP-13 (rs2252070) apresentaram menor tempo de sobrevida livre de doença e sobrevida global. Conclui-se que o SNP (rs2252070) da MMP-13 possui valor prognóstico em pacientes com carcinoma epidermóide oral e de orofaringe.

Malignant tumors have the ability to invade normal tissues and spread to distant anatomic sites, leading to metastasis, the whole factor for cancer mortality. Matrix metalloproteinases (MMP)-l and MMP-13 have been associated with tumor invasion and metastasis because MMP-1 degrades type I collagen, which is the most abundant substrate in the tumor stroma and MMP-13 degrades type IV collagen, among others, that is present in the basement membrane of the vessels. Research shows that IL-8 is a potent angiogenic factor and is associated with tumor growth, metastasis and poor prognosis of cancer. This study aims to verify the existence and frequency of polymorphisms in genes of MMP-1 (rs2071230 and rs470558), -13 (rs2252070) and IL-8 (rs4073 and rs2227532) and investigate the possible prognostic value of the same in cases of squamous cell carcinoma. Ninety eight samples from patients with oral and oropharyngeal squamous cell carcinoma and 134 control samples were genotyped by real-time PCR. All polymorphisms were in Hardy-Weinberg equilibrium, except SNP (rs2227532) of IL-8. The polymorphic homozygote genotype GG of MMP-1 (rs2071230) was found to be a risk factor just over 8 times for the development of oral and oropharyngeal squamous cell carcinoma, while the GG genotype polymorphism of MMP-13 (rs2252070) showed a protective effect of approximately 3 times. CC genotype of MMP-1 (rs470558) was most frequent in intraoral and CT in oropharyngeal lesions. TT genotype of the IL-8 (rs4073) was most common in intraoral lesions and III and IV clinical staging. Patients with GG genotype of MMP-13 (rs2252070) had fewer disease-free survival and overall survival. We conclude that the SNP (rs2252070) of MMP-13 has prognostic value in patients with oral and oropharyngeal squamous cell carcinoma.

Fatores de virulência de Streptococcus mutans e sua relação com a persistência e transmissão de genótipos entre membros de famílias brasileiras / Virulence factors of Streptococcus mutans and its relation to the persistence and transmission of genotypes among Brazilian family members

Streptococcus mutans (S. mutans) é considerado o principal agente etiológico da cárie dentária e estudos acerca de sua virulência têm sido realizados com o intuito de compreender melhor os mecanismos de patogenia da doença. Dentre outros fatores, a virulência dessa espécie bacteriana está relacionada a sua habilidade em produzir proteína ligante de glucano tipo A (GbpA) e mutacinas, proteínas que desempenham importante papel na adesão celular e colonização da superfície dentária. Desta forma, o objetivo da presente pesquisa foi analisar, geneticamente, esses fatores de virulência de S. mutans e verificar sua relação com a persistência e transmissão de genótipos entre os membros de oito famílias brasileiras. Foram utilizados 392 isolados clínicos de S. mutans obtidos a partir da saliva de 20 indivíduos adultos cárie-ativos. Os microrganismos foram previamente identificados e genotipados em um estudo anterior que avaliou sua transmissibilidade e estabilidade ao longo do tempo. As amostras estocadas a -86°C foram reativadas por semeadura em diferentes meios de cultura (ágar sangue e ágar Mitis Salivarius Bacitracina Sacarose) e repicadas em caldo de Infusão de Cérebro e Coração. Após extração do DNA cromossômico bacteriano foram realizadas análises genético-moleculares, por meio da reação em cadeia da polimerase, visando a detecção nas amostras dos genes envolvidos na produção de GbpA (gbpA) e codificadores dos tipos I, II, III e IV de mutacinas (mutAI, mutAII, mutAIII e mutAIV). Os dados obtidos foram analisados por meio das estatísticas descritiva e inferencial, utilizando-se os testes de Qui Quadrado, Odds Ratio (OR) e exato de Fisher, a um intervalo de confiança de 95% (IC95%) e nível de significância de 5%. Os genes gbpa, mutAI, mutAII, mutAIII e mutAIV foram detectados, respectivamente, em 77,3%, 12,5%, 51%, 16,6% e 89,8% dos isolados de S. mutans considerados viáveis (N=392). A virulência do S. mutans apresentou associação com sua...

Streptococcus mutans (S. mutans) is the main etiologic agent in the development of dental caries and several studies about its virulence have been conducted to understand the mechanisms of disease pathogenesis. Among other factors, the virulence of this bacterial species is based on their ability to produce glucan-binding protein-A (GbpA) and mutacins, proteins that play an important role in cell adhesion and colonization of the dental surface. Thus, the aim of the present study was to analyze, genetically, these virulence factors of S. mutans and to investigate their relation with the persistence and transmission of genotypes among the members from eight Brazilian families. A total of 392 clinical isolates of S. mutans, collected from 20 caries-active adults, were utilized. These microorganisms were previously identified and genotyped in a study that evaluated their transmissibility and stability over time. The samples stored at -86°C were plated on different culture media (blood agar and Mitis Salivarius Sucrose Bacitracin agar) and grown in Brain Heart Infusion broth. After extraction of bacterial chromosomal DNA, the samples were amplified, by the technique of polymerase chain reaction, for the presence of genes coding for GbpA (gbpA) and for mutacins types I, II, III and IV (mutAI, mutAII, mutAIII and mutAIV). Data obtained were analyzed through descriptive and inferential statistics, using the Chi-Square, Odds Ratio (OR) and Fisher's exact tests, with a 95% confidence interval (95%CI) and a significance level of 5%. The gbpa, mutAI, mutAII, mutAIII and mutAIV genes were detected, respectively, in 77.3%, 12.5%, 51%, 16.6% and 89.8% of viable clinical isolates (N=392). The virulence of S. mutans was associated with the transmission (P<0,001) and stability of colonization (P=0.011). The most virulent genotypes showed approximately three times more likely to be transmitted (OR=3.07; 95%CI 2.02 - 4.66) and approximately two times more likely to...

Fatores de virulência de Streptococcus mutans e sua relação com a persistência e transmissão de genótipos entre membros de famílias brasileiras / Virulence factors of Streptococcus mutans and its relation to the persistence and transmission of genotypes among Brazilian family members

Streptococcus mutans (S. mutans) é considerado o principal agente etiológico da cárie dentária e estudos acerca de sua virulência têm sido realizados com o intuito de compreender melhor os mecanismos de patogenia da doença. Dentre outros fatores, a virulência dessa espécie bacteriana está relacionada a sua habilidade em produzir proteína ligante de glucano tipo A (GbpA) e mutacinas, proteínas que desempenham importante papel na adesão celular e colonização da superfície dentária. Desta forma, o objetivo da presente pesquisa foi analisar, geneticamente, esses fatores de virulência de S. mutans e verificar sua relação com a persistência e transmissão de genótipos entre os membros de oito famílias brasileiras. Foram utilizados 392 isolados clínicos de S. mutans obtidos a partir da saliva de 20 indivíduos adultos cárie-ativos. Os microrganismos foram previamente identificados e genotipados em um estudo anterior que avaliou sua transmissibilidade e estabilidade ao longo do tempo. As amostras estocadas a -86°C foram reativadas por semeadura em diferentes meios de cultura (ágar sangue e ágar Mitis Salivarius Bacitracina Sacarose) e repicadas em caldo de Infusão de Cérebro e Coração. Após extração do DNA cromossômico bacteriano foram realizadas análises genético-moleculares, por meio da reação em cadeia da polimerase, visando a detecção nas amostras dos genes envolvidos na produção de GbpA (gbpA) e codificadores dos tipos I, II, III e IV de mutacinas (mutAI, mutAII, mutAIII e mutAIV). Os dados obtidos foram analisados por meio das estatísticas descritiva e inferencial, utilizando-se os testes de Qui Quadrado, Odds Ratio (OR) e exato de Fisher, a um intervalo de confiança de 95% (IC95%) e nível de significância de 5%. Os genes gbpa, mutAI, mutAII, mutAIII e mutAIV foram detectados, respectivamente, em 77,3%, 12,5%, 51%, 16,6% e 89,8% dos isolados de S. mutans considerados viáveis (N=392). A virulência do S. mutans apresentou associação com sua...

Streptococcus mutans (S. mutans) is the main etiologic agent in the development of dental caries and several studies about its virulence have been conducted to understand the mechanisms of disease pathogenesis. Among other factors, the virulence of this bacterial species is based on their ability to produce glucan-binding protein-A (GbpA) and mutacins, proteins that play an important role in cell adhesion and colonization of the dental surface. Thus, the aim of the present study was to analyze, genetically, these virulence factors of S. mutans and to investigate their relation with the persistence and transmission of genotypes among the members from eight Brazilian families. A total of 392 clinical isolates of S. mutans, collected from 20 caries-active adults, were utilized. These microorganisms were previously identified and genotyped in a study that evaluated their transmissibility and stability over time. The samples stored at -86°C were plated on different culture media (blood agar and Mitis Salivarius Sucrose Bacitracin agar) and grown in Brain Heart Infusion broth. After extraction of bacterial chromosomal DNA, the samples were amplified, by the technique of polymerase chain reaction, for the presence of genes coding for GbpA (gbpA) and for mutacins types I, II, III and IV (mutAI, mutAII, mutAIII and mutAIV). Data obtained were analyzed through descriptive and inferential statistics, using the Chi-Square, Odds Ratio (OR) and Fisher's exact tests, with a 95% confidence interval (95%CI) and a significance level of 5%. The gbpa, mutAI, mutAII, mutAIII and mutAIV genes were detected, respectively, in 77.3%, 12.5%, 51%, 16.6% and 89.8% of viable clinical isolates (N=392). The virulence of S. mutans was associated with the transmission (P<0,001) and stability of colonization (P=0.011). The most virulent genotypes showed approximately three times more likely to be transmitted (OR=3.07; 95%CI 2.02 - 4.66) and approximately two times more likely to...

Potencial influência de variantes genéticas nas disfunções temporomandibulares / Potential influence of genetic variants in temporomandibular disorders

O presente estudo teve como objetivos testar a hipótese nula de que não há diferença entre o grupo com Disfunção Temporomandibular (DTM) e o grupo Controle, para as frequências genotípicas e de alelos dos SNPs candidatos COMT Val(158)Met (rs4680); TNFA-308 (rs1800629); IL6-174 (rs1800795); IL-1β-3954 (rs1143634); IL10-592 (rs1800872); MMP1-1607 (rs1799750) e TLR4-896 (rs4986790); e determinar, nos casos com DTM, a influência dos SNPs candidatos na sensibilidade dolorosa mecânica experimental, na intensidade e no tempo de dor. As frequências genotípicas e de alelos dos sete SNPs candidatos foram comparadas entre 152 indivíduos com DTM e 91 controles, por meio da técnica de PCR em tempo real. A sensibilidade dolorosa mecânica foi avaliada pelo limiar de dor à palpação (LDP) e a intensidade de dor, utilizando-se uma escala analógica visual. As diferenças entre as frequências dos polimorfismos estudados foram avaliadas por meio do teste qui-quadrado (x2) e os valores de LDP entre os grupos foram comparados pelo teste t. A análise de possíveis diferenças entre os subgrupos de genótipos, com relação aos valores de LDP, EAV e tempo de dor, foi feita pelo teste estatístico one-way ANOVA, seguido pelo teste de Tukey. A hipótese nula foi rejeitada, uma vez que houve diferença entre as frequências genotípicas do SNP TNFA-308 entre os grupos, estando o polimorfismo TNFA-308 (1800629) associado às DTMs (p<0,05). Além do TNFA-308, os SNPs COMT Val(158)Met, IL6-174, IL-1β-3954 e TLR4-896 foram capazes de influenciar a sensibilidade dolorosa mecânica em indivíduos doentes (p<0,05). O presente estudo apresenta associação inédita entre o polimorfismo TNFA-308 (1800629) e as DTMs. Encorajamos estudos futuros que elucidem a associação entre genótipos pró-inflamatórios e uma menor sensibilidade dolorosa mecânica.

This study aimed at testing the null hypothesis which claims that there is no difference between the group with temporomandibular joint disorder (TMD) and a control group regarding the genotypic and allelic frequencies of the candidate SNPs COMT Val(158)Met (rs4680); TNFA-308 (rs1800629); IL6-174 (rs1800795); IL-1β-3954 (rs1143634); IL10-592 (rs1800872); MMP1-1607 (rs1799750) and TLR4-896 (rs4986790). Additionally, it aimed at determining candidate SNPs influence on experimental mechanical pain sensitivity, intensity and duration of pain in the TMD cases. The genotypic and allelic frequencies of the seven candidate SNPs were compared among 152 individuals from the group with TMD and 91 individuals from the control group, by using the real-time PCR technique. Mechanical pain sensitivity was assessed through pressure pain threshold (PPT) and pain intensity was assessed using visual analogue scales (VAS). Differences between the frequencies regarding the studied polymorphisms were assessed through the chi-square test (x2) while the PPT values were compared through the t-test. Analysis of potential differences between the genotype subgroups with respect to the PPT, VAS and pain duration values was performed with ANOVA one-way test, followed by the Tukeys test. The null hypothesis was rejected, since there were differences among the genotypic frequencies of the TNFA-308 SNP between groups. The TNFA-308 (1800629) polymorphism is found to be associated with the TMDs (p<0.05). In addition to TNFA-308, the SNPs COMT Val(158)Met, IL6-174, IL-1β-3954 and TLR4-896 were capable of influencing mechanical pain sensitivity in individuals with TMD (p<0.05). This study presents an unprecedented association between the TNFA-308 (1800629) polymorphism and TMDs. We encourage future researches that enlighten the association between proinflammatory genotypes and lower mechanical pain sensitivity.

Genetic polymorphism of Streptococcus mutans strains associated with incomplete caries removal

Aim: Despite the antibacterial properties of dental materials, the survival of residual bacteria under restorations has been demonstrated after incomplete caries removal. The aim of this study was to evaluate the genetic polymorphism of Streptococcus mutans strains isolated from deep dentinal lesions before and three months after incomplete caries removal. Methods: Samples of carious dentin were collected from 33 primary and/or permanent molars before and after indirect pulp treatment and processed for microbiological isolation of mutans streptococci (MS). After three months of the dental treatment, positive cultures for MS were detected in only ten of these teeth. DNA of MS isolates were obtained and subjected to polymerase chain reaction (PCR) for identification of S mutans. The arbitrary primed-PCR method (primer OPA-13) was used to detect the genetic polymorphism of S. mutans strains. Results: Identical or highly related S. mutans genotypes were observed in each tooth, regardless of the collect. Considering each tooth separately, a maximum of nine genotypic patterns were found in each tooth from all the collects. In addition, at least one genotypic pattern was repeated in the three collects. Genetic diversity was observed among the S. mutans isolates, obtained from different teeth after three months of the dental treatment. Conclusions: The persistence of identical genotypic patterns and the genetic similarity among the isolates, from the same tooth in distinct collects, showed the resistance of some S. mutans strains after incomplete caries removal treatment.