Metabolomic Signatures of In Vitro Biofilm Maturation of Streptococcus mutans.

The Streptococcus mutans is commonly find in oral environment in both symbiont and dysbiotic conditions, where for the last one it causes the break in homeostatic balance and, in association with other microorganisms' community, results in dental caries process. Additionally, it is important to determine the low molecular weight metabolites profile from Streptococcus mutans to distinguish the endogenous and exogenous compounds from patient subjected to salivary metabolomic studies. Thus, the objective of the present study was to characterize the in vitro metabolomic profile of the maturation of a single-species Streptococcus mutans biofilm using metabolomic approach by 1H-nuclear magnetic resonance (NMR) spectroscopy. A distinct metabolomic profile was observed after 2 days of biofilm maturation, independently of the presence of enamel substrate. Sucrose, lactate, and fructose were the main metabolites responsible for the distinction. The sucrose was consumed by S. mutans in higher levels in the initial experimental periods than at 6 days of biofilm growth. Lactate and fructose were the main compounds secreted, regardless of the type of growth, but it was also observed production of propionate, iso-butyrate, and pyruvate. Pyruvate metabolism and glycolysis/gluconeogenesis were the main pathways related to biofilm growth. The results contribute to the determination of compounds that are resulted from oral microbial activity and help to guide further metabolomics studies.

Salivary metabolome of children and adolescents under peritoneal dialysis.

OBJECTIVE: To study the influence of peritoneal dialysis (PD) on the salivary metabolite profile of children and adolescents with renal failure. MATERIALS AND METHODS: Healthy children/adolescents (n = 31; mean age: 12.18 ± 3.76) and children/adolescents subjected to PD (n = 12; mean age: 10.10 ± 4.25) were recruited. Oral health status assessed by the dmft/DMFT and Volpe-Manhold calculus indices. The 1H spectra were acquired in a 600-MHz Bruker nuclear magnetic resonance spectrometer and were subjected to multivariate analysis using partial least squares discriminant analysis (PLS-DA), orthogonal PLS-DA (O-PLS-DA), and univariate analysis through chi-square and t tests (SPSS 20.0, IL, USA), with a significance level of p < 0.05. RESULTS: A similar caries pattern (p = 0.57; chi-square test) was observed between the healthy (dmft = 0.72 ± 1.28 and DMFT 0.93 ± 2.30) and PD groups (dmft = 2.14 ± 3.67, DMFT 0.33 ± 0.71) and dental calculus (p > 0.05, t test). PLS-DA and O-PLS-DA were able to distinguish both groups (ACC = 0.85, R2 = 0.80, Q2 = 0.15). Salivary metabolites decrease in creatine, propionate, and sugar levels in the PD group and an increase in creatinine, butyrate, and lactate levels when compared with the healthy group. CONCLUSIONS: Children and adolescents subjected to PD have a different salivary metabolic profile from that of their healthy subjects. CLINICAL RELEVANCE: Complications of peritoneal dialysis procedures could be monitored by proper knowledge of saliva characteristics as predictors of peritonitis-related outcome. The use of metabolomics in pediatric nephrology may be an innovative methodology for the early diagnosis and monitoring of kidney diseases.

LACK OF ASSOCIATION BETWEEN HERPESVIRUS DETECTION IN SALIVA AND GINGIVITIS IN HIV­INFECTED CHILDREN.

The aims of this study were to compare the detection of human herpesviruses (HHVs) in the saliva of HIV-infected and healthy control children, and to evaluate associations between viral infection and gingivitis and immunodeficiency. Saliva samples were collected from 48 HIV-infected and 48 healthy control children. Clinical and laboratory data were collected during dental visits and from medical records. A trained dentist determined gingival indices and extension of gingivitis. Saliva samples were tested for herpes simplex virus types 1 and 2 (HSV-1 and HSV-2), varicella zoster virus (VZV), Epstein-Barr virus (EBV), and cytomegalovirus (CMV) by nested polymerase chain reaction assays. Thirty-five HIV-infected and 16 control children had gingivitis. Seventeen (35.4%) HIV-infected children and 13 (27%) control children were positive for HHVs. CMV was the most commonly detected HHV in both groups (HIV-infected, 25%; control, 12.5%), followed by HSV-1 (6.2% in both groups) and HSV-2 (HIV-infected, 4.2%; control, 8.3%). The presence of HHVs in saliva was not associated with the presence of gingivitis in HIV-1-infected children (p = 0.104) or healthy control children (p = 0.251), or with immunosuppression in HIV-infected individuals (p = 0.447). Gingivitis was correlated with HIV infection (p = 0.0001). These results suggest that asymptomatic salivary detection of HHVs is common in HIV-infected and healthy children, and that it is not associated with gingivitis.

Lack of associaiion between herpesvirus detectin in saliva and gingivitis in hhiv‑infected children / Ausência de associação entre a detecção de herpesvírus na saliva e gengivite em crianças infectadas pelo HIV

The aims of this study were to compare the detection of human herpesviruses (HHVs) in the saliva of HIV-infected and healthy control children, and to evaluate associations between viral infection and gingivitis and immunodeficiency. Saliva samples were collected from 48 HIV-infected and 48 healthy control children. Clinical and laboratory data were collected during dental visits and from medical records. A trained dentist determined gingival indices and extension of gingivitis. Saliva samples were tested for herpes simplex virus types 1 and 2 (HSV-1 and HSV-2), varicella zoster virus (VZV), Epstein-Barr virus (EBV), and cytomegalovirus (CMV) by nested polymerase chain reaction assays. Thirty-five HIV-infected and 16 control children had gingivitis. Seventeen (35.4%) HIV-infected children and 13 (27%) control children were positive for HHVs. CMV was the most commonly detected HHV in both groups (HIV-infected, 25%; control, 12.5%), followed by HSV-1 (6.2% in both groups) and HSV-2 (HIV-infected, 4.2%; control, 8.3%). The presence of HHVs in saliva was not associated with the presence of gingivitis in HIV-1-infected children (p = 0.104) or healthy control children (p = 0.251), or with immunosuppression in HIV-infected individuals (p = 0.447). Gingivitis was correlated with HIV infection (p = 0.0001). These results suggest that asymptomatic salivary detection of HHVs is common in HIV-infected and healthy children, and that it is not associated with gingivitis.

Os objetivos deste estudo foram detectar a presença de herpesvírus humanos (HHVs) na saliva de crianças infectadas pelo HIV, em comparação com controles saudáveis e avaliar a associação entre infecção viral, gengivite e imunodeficiência. Para este fim, foram colhidas amostras de saliva de 48 crianças HIV-positivas e 48 controles saudáveis. O índice gengival e extensão de gengivite foram determinados por um dentista treinado. Informações clínicas e laboratoriais foram obtidas durante a consulta odontológica e dos registros médicos. As amostras de saliva foram testadas para detecção de vírus herpes simplex tipos 1 e 2 (HSV-1 e HSV-2), vírus da varicela-zoster (VVZ), vírus Epistein-Barr (EBV) e citomegalovírus (CMV) através de nested-PCR. Trinta e cinco crianças HIV-positivas e 16 crianças do grupo controle apresentavam gengivite. Dezessete (35,4%) crianças HIV-positivas e 13 (27%) crianças controle testaram positivo para a presença de HHVs. CMV foi o vírus mais comum detectado em ambos os grupos (25% HIV-positivas e 12,5% de controle), seguido por HSV-1 (6,2% de ambos os grupos) e HSV-2 (4,2% HIV-positivas e 8,3% de controle). Não houve associação entre a detecção de HHVs na saliva e a presença de gengivite em ciranças HIV-positivas (p = 0.104) ou crianças saudáveis (p = 0,251), ou com imunossupressão em indivíduos HIV-positivos (p = 0,447). Foi observada uma correlação entre a infecção por HIV e a presença de gengivite (p = 0,0001). Os resultados sugerem que a detecção salivar assintomática de HHVs é comum entre crianças HIV-positivas e crianças saudáveis, e não está associada à gengivite.

Effect of serine-type protease of Candida spp. isolated from linear gingival erythema of HIV-positive children: critical factors in the colonization.

BACKGROUND: There are several kinds of oral soft tissue lesions that are common manifestations observed in human immunodeficiency virus (HIV)-infected children; for example, linear gingival erythema (LGE) that is a distinctive fiery red band along the margin of the gingivae. The etiology and pathogenesis of LGE are questionable, but a candidal origin has been suggested. Proteases are key virulence attributes produced by a variety of pathogenic fungi, including Candida. The objective of the present study is to identify the protease production in Candida species including, C. albicans (n=5), C. dubliniensis (n=1) and C. tropicalis (n=1), isolated directly from typical LGE lesions observed in six HIV-positive children, and also to test the effect of a serine protease inhibitor on the interaction of Candida spp. and epithelial cells in vitro. METHODS: The ability of Candida strains to release proteases in the culture supernatant fluids was visualized by gelatin-SDS-PAGE. Gel strips containing 30-fold concentrated supernatant (1.5×10(8) yeasts) were incubated at 37°C for 48 h in 50 mM sodium phosphate buffer, pH 5.5. The concentrated supernatants were also incubated with fibronectin, laminin, immunoglobulin G, bovine serum albumin and human serum albumin. The effect of serine protease inhibitor on the interaction of Candida spp. and epithelial cells (MA 104) was measured after pre-treatment of fungi with the inhibitor (phenylmethylsulphonyl fluoride, PMSF). RESULTS: All the extracellular proteases were completely inhibited by PMSF, identifying these activities as serine-type proteases. Interestingly, a common 62-kDa serine protease was observed in all Candida strains. The culture supernatants, rich in serine protease activities, cleaved several soluble proteinaceous substrates. Additionally, we demonstrated that pre-treatment of C. albicans, C. dubliniensis and C. tropicalis with PMSF diminished the interaction with epithelial cells. CONCLUSIONS: Collectively, our results show that Candida spp. isolated from LGE lesions produced and secreted serine proteases and these enzymes may be involved in the initial colonization events.

Child-OIDP index in Brazil: cross-cultural adaptation and validation.

BACKGROUND: Oral health-related quality of life (OHRQoL) measures are being increasingly used to introduce dimensions excluded by normative measures. Consequently, there is a need for an index which evaluates children's OHRQoL validated for Brazilian population, useful for oral health needs assessments and for the evaluation of oral health programs, services and technologies. The aim of this study was to do a cross-cultural adaptation of the Child Oral Impacts on Daily Performances (Child-OIDP) index, and assess its reliability and validity for application among Brazilian children between the ages of eleven and fourteen. METHODS: For cross-cultural adaptation, a translation/back-translation method integrated with expert panel reviews was applied. A total of 342 students from four public schools took part of the study. RESULTS: Overall, 80.7% of the sample reported at least one oral impact in the last three months. Cronbach's alpha was 0.63, the weighted kappa 0.76, and the intraclass correlation coefficient (ICC) 0.79. The index had a significant association with self-reported health measurements (self-rated oral health, satisfaction with oral health, perceived dental treatment needs, self-rated general health; all p < 0.01). CONCLUSION: It was concluded that the Child-OIDP index is a measure of oral health-related quality of life that can be applied to Brazilian children.

Salivary microbiota of HIV-positive children and its correlation with HIV status, oral diseases, and total secretory IgA.

AIM: This study aimed to investigate the prevalence and levels of salivary microorganisms in HIV-positive children, and their correlation to HIV status, oral lesions, and salivary IgA levels. DESIGN: Forty-two HIV-positive and 36 control children were clinically examined, had their saliva collected and processed for the microbiological analysis of 38 bacterial taxa by the checkerboard method, and salivary IgA quantification by ELISA. RESULTS: The majority of the species tested were more prevalent in control children than in the HIV group. Mean concentration of total salivary IgA was similar in both groups. High levels of Veillonella parvula were found in children with cheilitis and herpes. Tannerella forsythia, Eikenella Corrodens, and Propionibacterium acnes were prevalent in children with gingivitis, while Fusobacterium periodonticum, Streptococcus gordonii, and Streptococcus oralis were significantly more frequent in children with no oral lesions. Significant negative correlations between salivary IgA levels and Eubacterium nodatum and oral streptococci were observed (P < 0.05). CONCLUSION: HIV-seropositive children presented significantly lower prevalence and levels of several bacterial species in saliva; HIV-positive children are able to mount a mucosal immune response; HIV-seropositive children under highly active antiretroviral therapy presented low prevalence of oral lesions.