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1.
Oral (Basel) ; 3(2): 203-214, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38162993

RESUMO

Poor oral hygiene and excessive consumption of soda are among the main drivers of systemic health issues in adolescents in the United States. This non-randomized pilot clinical trial focused on the effects of a health text message system and smartphone-based intervention on adolescent tooth-brushing behavior and dietary choices, with a convenience sample of 94 participants aged 12 to 14 years old. A group of 75 participants agreed to use a tooth-brushing app and received a health text message; the other group of 15 agreed to use the tooth-brushing app, but did not receive a health text message. Saliva specimens were collected directly before and at the end of each experiment; changes in the salivary presence of cariogenic bacteria over the duration of the study were evaluated and compared with the demographics and behavioral variables. Within the text message group, 5% of participants increased the frequency of daily tooth brushing. Within the non-intervention group, 29% of participants increased the frequency of their daily tooth brushing. There were reductions in the total salivary bacteria and total streptococci in both groups (p < 0.001), but no change in the presence of cariogenic Mutans streptococci. Raising adolescents' consciousness of oral health behavior resulted in marginal to moderate improvements to oral hygiene and dietary choices, as well as reductions in total salivary bacteria.

2.
J Oral Microbiol ; 12(1): 1688449, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31893016

RESUMO

Background: Dental caries etiology is attributed to a dysbiotic imbalance within the plaque microbiome leading to a dominance of strong acidogens. Some studies that investigate the link between acidogens and caries quantify the recovery of acid tolerant strains on acid agar as a measure of acidogenic potential. This methodology assumes that acidogenic potential and acid tolerance are directly related. Aim: The validity of that assumption was investigated by statistically evaluating that relationship using streptococci recovered from children with or without a history of dental caries. Methods: Thirty streptococcal isolates were isolated from each of 13 subjects. Acidogenicity was quantified by measuring the terminal pH after overnight growth in Brain Heart Infusion (BHI) and Chemically Defined Medium (CDM). Acid tolerance was quantified by measuring the lowest pH acid agar displaying growth. Results: A significant difference in acidogenicity in CDM between levels of acid tolerance was found, but no significant difference in acidogenicity in BHI was noted. Moreover, there were no significant interactions between acid tolerance and caries history on acidogenicity measures in either medium. Conclusion: An ability to grow on acid agar below pH 5.0 is best aligned with strong acidogenicity and best able to distinguish between subjects with differing caries histories.

3.
BMC Oral Health ; 18(1): 129, 2018 07 31.
Artigo em Inglês | MEDLINE | ID: mdl-30064426

RESUMO

The mutans streptococci were once the primary focus of research dedicated to understanding the etiology of dental caries. That focus has now shifted to an emphasis on the ecological balances and complexities within the entirety of the plaque microbiome. Within that framework there are considerable differences of opinion regarding the importance and relative contributions of the mutans streptococci. This article explores the basis for the various viewpoints, the limitations of current knowledge, and the confounders that make it difficult to arrive at a consensus.


Assuntos
Cárie Dentária/microbiologia , Streptococcus mutans , Cárie Dentária/etiologia , Placa Dentária/microbiologia , Humanos , Microbiota , Modelos Biológicos
4.
J Microbiol Methods ; 139: 205-209, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28606792

RESUMO

Mutans streptococci (MS), specifically Streptococcus mutans (SM) and Streptococcus sobrinus (SS), are bacterial species frequently targeted for investigation due to their role in the etiology of dental caries. Differentiation of S. mutans and S. sobrinus is an essential part of exploring the role of these organisms in disease progression and the impact of the presence of either/both on a subject's caries experience. Of vital importance to the study of these organisms is an identification protocol that allows us to distinguish between the two species in an easy, accurate, and timely manner. While conducting a 5-year birth cohort study in a Northern Plains American Indian tribe, the need for a more rapid procedure for isolating and identifying high volumes of MS was recognized. We report here on the development of an accurate and rapid method for MS identification. Accuracy, ease of use, and material and time requirements for morphological differentiation on selective agar, biochemical tests, and various combinations of PCR primers were compared. The final protocol included preliminary identification based on colony morphology followed by PCR confirmation of species identification using primers targeting regions of the glucosyltransferase (gtf) genes of SM and SS. This method of isolation and identification was found to be highly accurate, more rapid than the previous methodology used, and easily learned. It resulted in more efficient use of both time and material resources.


Assuntos
Placa Dentária/microbiologia , Reação em Cadeia da Polimerase/métodos , Streptococcus mutans/isolamento & purificação , Streptococcus sobrinus/isolamento & purificação , Estudos de Coortes , Contagem de Colônia Microbiana , Primers do DNA , DNA Bacteriano/genética , Cárie Dentária/microbiologia , Feminino , Glucosiltransferases/genética , Humanos , Saliva/microbiologia , Streptococcus mutans/genética , Streptococcus sobrinus/genética , Fatores de Tempo
5.
Clin Exp Dent Res ; 3(6): 235-243, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-29416899

RESUMO

Early childhood caries is a complex health care issue that has a multifactorial etiology. One aspect of this etiology is the colonization and propagation of acidogenic bacteria at an early age. There have been several bacterial species associated with caries but 1 common species is Streptococcus mutans. Here, we describe genotypic diversity and commonality of Streptococcus mutans recovered from children representing 2 groups with similar socioeconomic demographics: a Northern Plains American Indian Tribe and a Southeast Iowa population. Forty 36-month-old American Indian children were selected from a cohort of 239 mothers and children, and forty 2- to 5-year-old children from Southeast Iowa were selected to compare the genotypic profiles of Streptococcus mutans recovered from each child's plaque. S. mutans isolates were selected from whole mouth plaque samples; DNA was extracted and amplified via AP-PCR to show specific genotype patterns. These patterns were compared with GelComparIIv6.5 gel analysis software. We found 18 distinct genotypes from 524 isolates; 13 of which were common between the 2 communities. Five genotypes were unique to only the American Indian children while the Southeast Iowa children harbored no unique genotypes. Although the American Indian children had some genotypes that were not present in the Southeast Iowa children, these were not widely distributed among the community. Furthermore, the levels of genotypic diversity and commonality were similar between the 2 populations. This study sets the groundwork for a comprehensive comparison of genotypes and caries among larger subsections of both populations.

6.
J Oral Microbiol ; 8: 32940, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27790973

RESUMO

BACKGROUND: Non-mutans low pH oral streptococci are postulated to contribute to caries etiology. OBJECTIVE: This study was undertaken to investigate whether the acidogenicity and acid tolerance of clinical strains of Streptococcus oralis and Streptococcus mitis correlate with health or early-stage enamel caries. DESIGN: S. oralis and S. mitis were isolated from plaque samples taken from the occlusal surfaces of second molars sampled at two different visits 4 years apart. All sites were sound at Visit 1; subjects were segregated into one of three groups based on the status of the site at Visit 2 and caries elsewhere in the dentition. Strains of S. oralis and S. mitis were evaluated for acidogenicity and acid tolerance, and the results correlated with the clinical status of the sites from which they were isolated. Mutans streptococci (MS) isolated from the plaque samples were also quantified, and the presence or absence of growth on pH 5.5 media or on media selective for bifidobacteria was recorded. RESULTS: No significant positive correlations were found between the acidogenicity properties of the S. oralis and S. mitis clones and caries at either visit. Similar results were obtained for acid tolerance of S. oralis clones but were inconclusive for S. mitis clones. A statistically significant positive correlation between MS levels and caries (or future caries) was evident at both visits, but there were no statistical correlations with the growth on pH 5.5 media or media selective for bifidobacteria. CONCLUSIONS: The low pH potential likely varies considerably among oral streptococcal species and is least likely to be found among strains of S. mitis. Accordingly, the concept and constitution of 'low pH streptococci' may need to be re-evaluated.

7.
J Public Health Dent ; 76(4): 259-262, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-26992441

RESUMO

OBJECTIVES: To compare timing of tooth emergence among groups of American Indian (AI), Black and White children in the United States at 12 months of age. METHODS: Data were from two sources - a longitudinal study of a Northern Plains tribal community and a study with sites in Indiana, Iowa and North Carolina. For the Northern Plains study, all children (n = 223) were American Indian, while for the multisite study, children (n = 320) were from diverse racial groups. Analyses were limited to data from examinations conducted within 30 days of the child's first birthday. RESULTS: AI children had significantly more teeth present (Mean: 7.8, Median: 8.0) than did Whites (4.4, 4.0, P < 0.001) or Blacks (4.5, 4.0, P < 0.001). No significant differences were detected between Black and White children (P = 0.58). There was no significant sex difference overall or within any of the racial groups. CONCLUSIONS: Tooth emergence occurs at a younger age for AI children than it does for contemporary White or Black children in the United States.


Assuntos
Etnicidade , Erupção Dentária/fisiologia , Dente Decíduo , Feminino , Humanos , Lactente , Estudos Longitudinais , Masculino , Estados Unidos
8.
Community Dent Oral Epidemiol ; 44(2): 154-61, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26544674

RESUMO

OBJECTIVES: Early childhood caries (ECC) is rampant among American Indian children, but there has been relatively little study of this problem. This article reports on risk factors for caries for a group of American Indian children at age 36 months as part of a longitudinal study. METHODS: Pregnant women from a Northern Plains Tribal community were recruited to participate in a longitudinal study of caries and caries risk factors. Standardized dental examinations were completed on children, and questionnaires were completed by mothers at baseline and when children were 4, 8, 12, 16, 22, 28, and 36 months of age. Examinations were surface-specific for dental caries, and the questionnaires collected data on demographic, dietary, and behavioral factors. Nonparametric bivariate tests and logistic regression models were used to identify risk factors for caries at 36 months, and negative binomial regression was used to identify factors related to caries severity (dmf counts). RESULTS: Among the 232 children, and caries prevalence for cavitated lesions was 80%, with an additional 15% having only noncavitated lesions. The mean dmfs was 9.6, and of the total dmfs, nearly 62% of affected surfaces were decayed, 31% were missing, and 7% were filled. Logistic regression identified higher added-sugar beverage consumption, younger maternal age at baseline, higher maternal DMFS at baseline, and greater number of people in the household as significant (P < 0.05) risk factors. Negative binomial regression found that only maternal DMFS was associated with child dmf counts. CONCLUSIONS: By the age of 36 months, dental caries is nearly universal in this population of American Indian children. Caries risk factors included sugared beverage consumption, greater household size, and maternal factors, but further analyses are needed to better understand caries in this population.


Assuntos
Cárie Dentária/epidemiologia , Indígenas Norte-Americanos/estatística & dados numéricos , Pré-Escolar , Índice CPO , Feminino , Humanos , Estudos Longitudinais , Masculino , Prevalência , Fatores de Risco , Estados Unidos/epidemiologia
9.
J Bacteriol ; 198(1): 157-67, 2016 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-26483519

RESUMO

UNLABELLED: Lipids endogenous to skin and mucosal surfaces exhibit potent antimicrobial activity against Porphyromonas gingivalis, an important colonizer of the oral cavity implicated in periodontitis. Our previous work demonstrated the antimicrobial activity of the fatty acid sapienic acid (C(16:1Δ6)) against P. gingivalis and found that sapienic acid treatment alters both protein and lipid composition from those in controls. In this study, we further examined whole-cell protein differences between sapienic acid-treated bacteria and untreated controls, and we utilized open-source functional association and annotation programs to explore potential mechanisms for the antimicrobial activity of sapienic acid. Our analyses indicated that sapienic acid treatment induces a unique stress response in P. gingivalis resulting in differential expression of proteins involved in a variety of metabolic pathways. This network of differentially regulated proteins was enriched in protein-protein interactions (P = 2.98 × 10(-8)), including six KEGG pathways (P value ranges, 2.30 × 10(-5) to 0.05) and four Gene Ontology (GO) molecular functions (P value ranges, 0.02 to 0.04), with multiple suggestive enriched relationships in KEGG pathways and GO molecular functions. Upregulated metabolic pathways suggest increases in energy production, lipid metabolism, iron acquisition and processing, and respiration. Combined with a suggested preferential metabolism of serine, which is necessary for fatty acid biosynthesis, these data support our previous findings that the site of sapienic acid antimicrobial activity is likely at the bacterial membrane. IMPORTANCE: P. gingivalis is an important opportunistic pathogen implicated in periodontitis. Affecting nearly 50% of the population, periodontitis is treatable, but the resulting damage is irreversible and eventually progresses to tooth loss. There is a great need for natural products that can be used to treat and/or prevent the overgrowth of periodontal pathogens and increase oral health. Sapienic acid is endogenous to the oral cavity and is a potent antimicrobial agent, suggesting a potential therapeutic or prophylactic use for this fatty acid. This study examines the effects of sapienic acid treatment on P. gingivalis and highlights the membrane as the likely site of antimicrobial activity.


Assuntos
Proteínas de Bactérias/metabolismo , Regulação Bacteriana da Expressão Gênica/fisiologia , Ácidos Palmíticos/farmacologia , Porphyromonas gingivalis/efeitos dos fármacos , Porphyromonas gingivalis/metabolismo , Mapas de Interação de Proteínas/fisiologia , Aminoácidos/metabolismo , Proteínas de Bactérias/genética , Metabolismo Energético , Consumo de Oxigênio/efeitos dos fármacos , Consumo de Oxigênio/fisiologia , Mapas de Interação de Proteínas/efeitos dos fármacos
10.
J Oral Microbiol ; 7: 27182, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25840611

RESUMO

BACKGROUND: Severe-early childhood caries (S-ECC) is one of the most common infectious diseases in children and is prevalent in lower socio-economic populations. American Indian children suffer from the highest levels of S-ECC in the United States. Members of the mutans streptococci, Streptococcus mutans, in particular, are key etiologic agents in the development of caries. Children typically acquire S. mutans from their mothers and early acquisition is often associated with higher levels of tooth decay. METHODS: We have conducted a 5-year birth cohort study with a Northern Plains Tribe to determine the temporality and fidelity of S. mutans transmission from mother to child in addition to the genotypic diversity of S. mutans in this community. Plaque samples were collected from 239 mother/child dyads at regular intervals from birth to 36 months and S. mutans were isolated and genotyped by arbitrarily primed-polymerase chain reaction (AP-PCR). RESULTS: Here we present preliminary findings from a subset of the cohort. The focus for this paper is on initial acquisition events in the children. We identified 17 unique genotypes in 711 S. mutans isolates in our subset of 40 children, 40 mothers and 14 primary caregivers. Twelve of these genotypes were identified in more than one individual. S. mutans colonization occurred by 16 months in 57.5% of the children and early colonization was associated with higher decayed, missing and filled surface (DMFS) scores (p=0.0007). Children colonized by S. mutans shared a common genotype with their mothers 47.8% of the time. While multiple genotypes were common in adults, only 10% of children harbored multiple genotypes. CONCLUSION: These children acquire S. mutans at an earlier age than the originally described 'window of infectivity' and often, but not exclusively, from their mothers. Early acquisition is associated with both the caries status of the children and the mothers.

11.
Biochim Biophys Acta ; 1841(3): 319-22, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23994607

RESUMO

Lauric acid (C12:0) and sapienic acid (C16:1Δ6) derived from human sebaceous triglycerides are potent antimicrobials found at the human skin surface. Long-chain bases (sphingosine, dihydrosphingosine and 6-hydroxysphingosine) are also potent and broad-acting antimicrobials normally present at the skin surface. These antimicrobials are generated through the action of ceramidases on ceramides from the stratum corneum. These natural antimicrobials are thought to be part of the innate immune system of the skin. Exogenously providing these lipids to the skin may provide a new therapeutic option, or could potentially provide prophylaxis in people at risk of infection. This article is part of a Special Issue entitled The Important Role of Lipids in the Epidermis and their Role in the Formation and Maintenance of the Cutaneous Barrier. Guest Editors: Kenneth R. Feingold and Peter Elias.


Assuntos
Anti-Infecciosos/metabolismo , Infecções/metabolismo , Metabolismo dos Lipídeos , Lipídeos , Pele/metabolismo , Animais , Ceramidases/metabolismo , Humanos , Controle de Infecções
12.
Int J Oral Sci ; 5(3): 130-40, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23867843

RESUMO

Oral mucosal and salivary lipids exhibit potent antimicrobial activity for a variety of Gram-positive and Gram-negative bacteria; however, little is known about their spectrum of antimicrobial activity or mechanisms of action against oral bacteria. In this study, we examine the activity of two fatty acids and three sphingoid bases against Porphyromonas gingivalis, an important colonizer of the oral cavity implicated in periodontitis. Minimal inhibitory concentrations, minimal bactericidal concentrations, and kill kinetics revealed variable, but potent, activity of oral mucosal and salivary lipids against P. gingivalis, indicating that lipid structure may be an important determinant in lipid mechanisms of activity against bacteria, although specific components of bacterial membranes are also likely important. Electron micrographs showed ultrastructural damage induced by sapienic acid and phytosphingosine and confirmed disruption of the bacterial plasma membrane. This information, coupled with the association of treatment lipids with P. gingivalis lipids revealed via thin layer chromatography, suggests that the plasma membrane is a likely target of lipid antibacterial activity. Utilizing a combination of two-dimensional in-gel electrophoresis and Western blot followed by mass spectroscopy and N-terminus degradation sequencing we also show that treatment with sapienic acid induces upregulation of a set of proteins comprising a unique P. gingivalis stress response, including proteins important in fatty acid biosynthesis, metabolism and energy production, protein processing, cell adhesion and virulence. Prophylactic or therapeutic lipid treatments may be beneficial for intervention of infection by supplementing the natural immune function of endogenous lipids on mucosal surfaces.


Assuntos
Antibacterianos/farmacologia , Proteínas de Bactérias/efeitos dos fármacos , Lipídeos/farmacologia , Mucosa Bucal/química , Mucosa Bucal/imunologia , Porphyromonas gingivalis/efeitos dos fármacos , Contagem de Colônia Microbiana , Ácidos Graxos/farmacologia , Humanos , Microscopia Eletrônica , Mucosa Bucal/microbiologia , Porphyromonas gingivalis/química , Porphyromonas gingivalis/ultraestrutura , Saliva/química , Saliva/microbiologia , Esfingolipídeos/farmacologia , Virulência/efeitos dos fármacos
13.
Pediatr Dent ; 35(3): 241-6, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23756308

RESUMO

PURPOSE: The purpose was to compare whether mothers exposed to an autonomy-supportive psychoeducational videotaped message, informed by the self-determination theory (SDT), demonstrated greater changes in oral health knowledge and behavioral intentions as a preventive means for early childhood caries (ECC) than mothers exposed to a neutral message delivered by brochure. METHODS: Data were collected at baseline, one-, and six-month follow-ups from 415 12- to 49-month-old WIC-enrolled children and their mothers: 283 in the video intervention group and 132 in the brochure control group. Mothers completed questionnaires on maternal knowledge and behavioral intentions for oral health care. Chi-square, Wilcoxon rank-sum, and Mann-Whitney tests were used to analyze data (P<.05). RESULTS: Relative to their baseline scores, the intervention group showed a greater increase in knowledge than the control group, both at one-month (P=.002) and six-month follow-ups (P<.001). The video group also demonstrated a greater increase in behavioral intentions than controls, both at one-month (P<.05) and six-month follow-ups (P<.001). Knowledge and behavioral intention levels at six-month follow-up did not differ significantly from those at one-month follow-up, indicating that intervention-based increases in these measures were maintained over time. CONCLUSIONS: Data provided evidence of the effectiveness of the autonomy-supportive psychoeducational intervention for ECC prevention relative to a neutral brochure.


Assuntos
Cárie Dentária/prevenção & controle , Educação em Saúde/métodos , Conhecimentos, Atitudes e Prática em Saúde , Mães/psicologia , Motivação , Higiene Bucal , Autonomia Pessoal , Adulto , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Mães/educação , Inquéritos e Questionários
14.
Pediatr Dent ; 35(3): 247-51, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23756309

RESUMO

PURPOSE: The purpose was to compare whether mothers exposed to an autonomy-supportive psychoeducational videotaped message, informed by self-determination theory (SDT), demonstrated greater changes in behavior concerning their children's oral health than mothers exposed to a neutral message delivered by brochure. METHODS: Data were collected at baseline, one- and six-month follow-ups from 415 12- to 49-month-old WIC-enrolled children and their mothers: 283 in the video intervention group and 132 in the brochure control group. Mothers completed questionnaires regarding their child's dietary/oral hygiene habits. Chi-square, Wilcoxon Signed Rank, Mann-Whitney, and McNemar tests were used to analyze data (P<0.05). RESULTS: Significantly more positive changes were observed for dietary/oral hygiene behaviors among the intervention group mothers at one- and six-month follow-ups than for the controls. Significantly fewer mothers in the intervention group shared dining ware with their child at both one- (P=0.0046) and six-month follow-ups (P<0.0001); this practice was decreased only at six-months for the control group mothers (P=0.05). Restricting consideration only to mothers who were not checking for white spot lesions at baseline, a significantly greater proportion of mothers in the intervention group performed this behavior at six-months (P=0.0044). CONCLUSIONS: Data provided evidence of the effectiveness of the SDT videotaped oral health message relative to a neutral brochure.


Assuntos
Cárie Dentária/prevenção & controle , Comportamento Alimentar , Comportamentos Relacionados com a Saúde , Educação em Saúde/métodos , Conhecimentos, Atitudes e Prática em Saúde , Mães/psicologia , Higiene Bucal/métodos , Adulto , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Mães/educação , Inquéritos e Questionários
15.
J Public Health Dent ; 72(4): 269-78, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22506597

RESUMO

OBJECTIVES: The objective of this study is to assess relationships between the presence or absence of mutans streptococci (MS) and other covariates in children aged 12-49 months. METHODS: Data were analyzed using baseline information from 411 children enrolled in the Special Supplemental Food Program for Women, Infants and Children (WIC) who participated in a psychoeducational study in Iowa. Children were assessed for MS using a semiquantitative method (RODAC plates). Dental examinations using d(1) d(2) .(3) criteria and presence of visible plaque on incisors and molars were completed. Mothers completed a series of detailed questionnaires regarding their child's oral health, their socioeconomic status, their child's dietary/oral hygiene habits, and beverage consumption, among other behaviors. Bivariate relationships with the presence of MS were assessed and followed by multivariable modeling using logistic regression (alpha = 0.05). RESULTS: MS was present in 144 children (35 percent). Bivariate relationships with MS presence were identified for multiple covariates that included demographic characteristics, type of beverage consumption, dental caries, and plaque measures. Multivariate logistic regression modeling suggested that MS presence in children was positively associated with nonwhite race of the child, number of teeth present, presence of cavitated lesions, proportion of teeth with plaque, and lower levels of maternal education. CONCLUSIONS: The presence of MS was associated with greater caries and plaque scores and with low maternal education and nonwhite racial background.


Assuntos
Placa Dentária/microbiologia , Assistência Alimentar , Streptococcus mutans , Pré-Escolar , Sacarose Alimentar/efeitos adversos , Escolaridade , Feminino , Assistência Alimentar/organização & administração , Humanos , Lactente , Transmissão Vertical de Doenças Infecciosas , Iowa , Modelos Logísticos , Mães , Estado Nutricional , Razão de Chances , Higiene Bucal/métodos , Higiene Bucal/estatística & dados numéricos , Pobreza , Fatores de Risco , Streptococcus mutans/isolamento & purificação , Streptococcus sobrinus/isolamento & purificação , Estados Unidos
16.
Antimicrob Agents Chemother ; 56(3): 1157-61, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22155833

RESUMO

There is growing evidence that the role of lipids in innate immunity is more important than previously realized. How lipids interact with bacteria to achieve a level of protection, however, is still poorly understood. To begin to address the mechanisms of antibacterial activity, we determined MICs and minimum bactericidal concentrations (MBCs) of lipids common to the skin and oral cavity--the sphingoid bases D-sphingosine, phytosphingosine, and dihydrosphingosine and the fatty acids sapienic acid and lauric acid--against four Gram-negative bacteria and seven Gram-positive bacteria. Exact Kruskal-Wallis tests of these values showed differences among lipid treatments (P < 0.0001) for each bacterial species except Serratia marcescens and Pseudomonas aeruginosa. D-sphingosine (MBC range, 0.3 to 19.6 µg/ml), dihydrosphingosine (MBC range, 0.6 to 39.1 µg/ml), and phytosphingosine (MBC range, 3.3 to 62.5 µg/ml) were active against all bacteria except S. marcescens and P. aeruginosa (MBC > 500 µg/ml). Sapienic acid (MBC range, 31.3 to 375.0 µg/ml) was active against Streptococcus sanguinis, Streptococcus mitis, and Fusobacterium nucleatum but not active against Escherichia coli, Staphylococcus aureus, S. marcescens, P. aeruginosa, Corynebacterium bovis, Corynebacterium striatum, and Corynebacterium jeikeium (MBC > 500 µg/ml). Lauric acid (MBC range, 6.8 to 375.0 µg/ml) was active against all bacteria except E. coli, S. marcescens, and P. aeruginosa (MBC > 500 µg/ml). Complete killing was achieved as early as 0.5 h for some lipids but took as long as 24 h for others. Hence, sphingoid bases and fatty acids have different antibacterial activities and may have potential for prophylactic or therapeutic intervention in infection.


Assuntos
Antibacterianos/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Imunidade Inata , Boca/imunologia , Pele/imunologia , Antibacterianos/imunologia , Bactérias Gram-Negativas/crescimento & desenvolvimento , Infecções por Bactérias Gram-Negativas/imunologia , Infecções por Bactérias Gram-Negativas/prevenção & controle , Bactérias Gram-Positivas/crescimento & desenvolvimento , Infecções por Bactérias Gram-Positivas/imunologia , Infecções por Bactérias Gram-Positivas/prevenção & controle , Humanos , Ácidos Láuricos/imunologia , Ácidos Láuricos/metabolismo , Ácidos Láuricos/farmacologia , Testes de Sensibilidade Microbiana , Boca/microbiologia , Ácidos Palmíticos/imunologia , Ácidos Palmíticos/metabolismo , Ácidos Palmíticos/farmacologia , Pele/microbiologia , Especificidade da Espécie , Esfingosina/análogos & derivados , Esfingosina/imunologia , Esfingosina/metabolismo , Esfingosina/farmacologia
17.
Arch Oral Biol ; 56(6): 588-91, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21247555

RESUMO

OBJECTIVE: The purpose of this study was to determine the presence and relative composition of neutral lipids in human saliva. DESIGN: Whole unstimulated saliva was collected from 12 subjects ranging from 21 to 29 years old. Samples were lyophilized, and lipids were extracted using chloroform-methanol. Lipids were analysed by thin-layer chromatography. RESULTS: Human saliva contains cholesterol, fatty acids, triglycerides, wax esters, cholesterol esters and squalene. The mean total neutral lipid content was 12.1±6.3 µg/ml. CONCLUSIONS: These lipids in human saliva closely resemble the lipids found on the skin surface. These salivary lipids are most likely produced by the sebaceous follicles in the oral mucosa and sebaceous glands associated with major salivary glands.


Assuntos
Ésteres/análise , Saliva/química , Esqualeno/análise , Ceras/análise , Adulto , Cromatografia em Camada Fina , Feminino , Humanos , Masculino
18.
J Endod ; 36(11): 1874-8, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20951304

RESUMO

INTRODUCTION: The purpose of this study was to determine bactericidal efficacy of 0.04% stabilized chlorine dioxide, 3% sodium hypochlorite, 2% chlorhexidine gluconate, and sterile distilled water in a polymicrobial biofilm model. METHODS: Roots of 35 permanent bovine incisors had pulps extirpated, and their apical size and root length were standardized. Teeth were coated with mucin, inoculated with standardized suspensions of Streptococcus sanguinis, Actinomyces viscosus, Fusobacterium nucleatum, Peptostreptococcus micros, and Prevotella nigrescens and incubated anaerobically. Teeth were randomly divided into four groups and rinsed for 3 minutes with 15 mL of irrigant. Biofilms were harvested and spiral-plated on selective media. Numbers of bacteria in the harvested biofilms was determined via the standard spiral-plating methodology. Treatment groups were evaluated using the nonparametric Kruskal-Wallis procedure. Pair-wise comparisons among the four groups and five organisms were made using the Wilcoxon-Mann-Whitney procedure. Adjustments for multiple comparisons were made using the Holm method with p < 0.05. RESULTS: Results provide strong evidence of a significant difference in levels of bactericidal activity associated with the type of irrigant for all five bacterial species tested. Levels of bactericidal activity were significantly higher for the NaOCl group than for the stabilized chlorine dioxide (ClO2) group for S. sanguinis, A. viscosus, and P. nigrescens. Results for F. nucleatum and P. micros were not significant after the adjustment for multiple comparisons. CONCLUSIONS: The triple-inoculation bovine tooth model system is a robust, consistent, and reproducible model system to study polymicrobial biofilms. It should be used with the knowledge expansion of biofilm structure and function as well as the development of antimicrobial protocols.


Assuntos
Biofilmes/efeitos dos fármacos , Compostos Clorados/farmacologia , Desinfetantes de Equipamento Odontológico/farmacologia , Cavidade Pulpar/microbiologia , Óxidos/farmacologia , Irrigantes do Canal Radicular/farmacologia , Actinomyces viscosus/efeitos dos fármacos , Animais , Anti-Infecciosos Locais/farmacologia , Carga Bacteriana , Técnicas Bacteriológicas , Bovinos , Clorexidina/análogos & derivados , Clorexidina/farmacologia , Fusobacterium nucleatum/efeitos dos fármacos , Incisivo/microbiologia , Teste de Materiais , Viabilidade Microbiana/efeitos dos fármacos , Microscopia Eletrônica de Varredura , Peptostreptococcus/efeitos dos fármacos , Prevotella nigrescens/efeitos dos fármacos , Distribuição Aleatória , Hipoclorito de Sódio/farmacologia , Streptococcus/efeitos dos fármacos , Fatores de Tempo , Água
19.
Artigo em Inglês | MEDLINE | ID: mdl-19451008

RESUMO

OBJECTIVE: This study evaluated the ability of a resin-based system (Resilon/Epiphany) and gutta-percha/sealer with warm vertical or cold lateral compaction to prevent coronal leakage. STUDY DESIGN: A polymicrobial suspension in a dual-chamber model was used. Seventy extracted maxillary incisors were prepared, divided into 4 groups, and obturated: Group 1, lateral compaction/gutta-percha/AH Plus; Group 2, lateral compaction/Resilon; Group 3, continuous wave compaction/gutta-percha/AH Plus; Group 4, continuous wave compaction/Resilon. Upper chambers held a mixed suspension of endodontic pathogens. Apices were suspended in the lower chambers. Leakage was determined daily for 40 days and evaluated for turbidity. Data were analyzed using survival analysis; log-rank test was used to analyze differences in time to leakage. RESULTS: Median time to leakage: 16, 15, 11, and 25 days for Groups 1 to 4 respectively (P = .93, log-rank test). CONCLUSION: No difference in time to leakage among the 4 treatment groups existed.


Assuntos
Infiltração Dentária/prevenção & controle , Materiais Restauradores do Canal Radicular/química , Obturação do Canal Radicular/métodos , Infiltração Dentária/microbiologia , Cavidade Pulpar/microbiologia , Falha de Restauração Dentária , Resinas Epóxi/química , Guta-Percha/química , Humanos , Incisivo , Estudos Longitudinais , Maxila
20.
Community Dent Oral Epidemiol ; 37(2): 116-22, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19046332

RESUMO

OBJECTIVES: Early childhood caries (ECC) is a challenging public health problem in the United States and elsewhere; however, there is limited information concerning risk factors in very young children. The purpose of this study was to assess baseline risk factors for 18-month caries prevalence as part of a longitudinal study of high-risk children. METHODS: About 212 children, 6-24 months of age were recruited from a rural community in Iowa. Subjects were enrolled in the WIC program, which provides nutritional support for low-income families with children. Dental examinations using d1, d2-3 criteria were conducted at baseline and after 18 months. Caries prevalence was determined at the frank decay level (d2-3 or filled surfaces), as well as at the noncavitated level (d1), and combined (d1, d2-3 or f surfaces). Risk factor data were collected at baseline and after 9- and 18- months. These data included beverage consumption data, presence of visible plaque, and use of fluoride toothpaste for children as well as mutans streptococci (MS) levels of mothers and children and family sociodemographic factors. RESULTS: About 128 children (60%) remained in the study after 18 months. Among these children, prevalence of d1,d2-3/f level caries increased from 9% to 77%, while d2-3/f level caries increased from 2% to 20%. Logistic regression models for baseline predictors of d2-3f caries at the 18-month follow-up found the presence of MS in children (OR=4.4; 95% CI: 1.4, 13.9) and sugar-sweetened beverages (OR=3.0; 95% CI: 1.1, 8.6) to be the only significant risk factors. Sociodemographic factors and the use of fluoride toothpaste were not significant in these models. CONCLUSIONS: Results suggest that early colonization by MS and consumption of sugar-sweetened beverages are significant predictors of ECC in high-risk populations.


Assuntos
Cárie Dentária/economia , Cárie Dentária/epidemiologia , Pobreza , Alimentação com Mamadeira/efeitos adversos , Cariostáticos/uso terapêutico , Cárie Dentária/etiologia , Placa Dentária/microbiologia , Sacarose Alimentar/efeitos adversos , Fluoretos/uso terapêutico , Humanos , Lactente , Modelos Logísticos , Estudos Longitudinais , Prevalência , Fatores de Risco , Saliva/microbiologia , Estatísticas não Paramétricas , Streptococcus mutans/isolamento & purificação , Cremes Dentais/química , Estados Unidos/epidemiologia
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