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1.
Int J Oral Sci ; 5(1): 21-5, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23538641

RESUMO

The objective of this study was to investigate the compositional profiles and microbial shifts of oral microbiota during head-and-neck radiotherapy. Bioinformatic analysis based on 16S rRNA gene pyrosequencing was performed to assess the diversity and variation of oral microbiota of irradiated patients. Eight patients with head and neck cancers were involved in this study. For each patient, supragingival plaque samples were collected at seven time points before and during radiotherapy. A total of 147,232 qualified sequences were obtained through pyrosequencing and bioinformatic analysis, representing 3,460 species level operational taxonomic units (OTUs) and 140 genus level taxa. Temporal variations were observed across different time points and supported by cluster analysis based on weighted UniFrac metrics. Moreover, the low evenness of oral microbial communities in relative abundance was revealed by Lorenz curves. This study contributed to a better understanding of the detailed characterization of oral bacterial diversity of irradiated patients.


Assuntos
Bactérias/classificação , Placa Dentária/microbiologia , Neoplasias de Cabeça e Pescoço/radioterapia , Actinomyces/classificação , Actinomyces/efeitos da radiação , Actinomycetaceae/classificação , Actinomycetaceae/efeitos da radiação , Alcaligenaceae/classificação , Alcaligenaceae/efeitos da radiação , Bactérias/efeitos da radiação , Capnocytophaga/classificação , Capnocytophaga/efeitos da radiação , Carnobacteriaceae/classificação , Carnobacteriaceae/efeitos da radiação , Biologia Computacional , Seguimentos , Gemella/classificação , Gemella/efeitos da radiação , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Pessoa de Meia-Idade , Neisseria/classificação , Neisseria/efeitos da radiação , Prevotella/classificação , Prevotella/efeitos da radiação , Propionibacteriaceae/classificação , Propionibacteriaceae/efeitos da radiação , RNA Bacteriano/análise , RNA Ribossômico 16S/análise , Streptococcus/classificação , Streptococcus/efeitos da radiação , Veillonella/classificação , Veillonella/efeitos da radiação
2.
PLoS One ; 8(2): e56343, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23437114

RESUMO

Radiotherapy is the primary treatment modality used for patients with head-and-neck cancers, but inevitably causes microorganism-related oral complications. This study aims to explore the dynamic core microbiome of oral microbiota in supragingival plaque during the course of head-and-neck radiotherapy. Eight subjects aged 26 to 70 were recruited. Dental plaque samples were collected (over seven sampling time points for each patient) before and during radiotherapy. The V1-V3 hypervariable regions of bacterial 16S rRNA genes were amplified, and the high-throughput pyrosequencing was performed. A total of 140 genera belonging to 13 phyla were found. Four phyla (Actinobacteria, Bacteroidetes, Firmicutes, and Proteobacteria) and 11 genera (Streptococcus, Actinomyces, Veillonella, Capnocytophaga, Derxia, Neisseria, Rothia, Prevotella, Granulicatella, Luteococcus, and Gemella) were found in all subjects, supporting the concept of a core microbiome. Temporal variation of these major cores in relative abundance were observed, as well as a negative correlation between the number of OTUs and radiation dose. Moreover, an optimized conceptual framework was proposed for defining a dynamic core microbiome in extreme conditions such as radiotherapy. This study presents a theoretical foundation for exploring a core microbiome of communities from time series data, and may help predict community responses to perturbation as caused by exposure to ionizing radiation.


Assuntos
Placa Dentária/microbiologia , Neoplasias de Cabeça e Pescoço/microbiologia , Neoplasias de Cabeça e Pescoço/radioterapia , Metagenoma/genética , Análise de Sequência de DNA/métodos , Temperatura , Adulto , Idoso , Bactérias/genética , Relação Dose-Resposta à Radiação , Variação Genética , Humanos , Pessoa de Meia-Idade , Fatores de Tempo
3.
J Radiat Res ; 52(6): 834-9, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22104273

RESUMO

This study aimed to evaluate changes in the biodiversity of the oral microflora of patients with head and neck cancer treated with postoperative intensity-modulated radiotherapy (IMRT) or conventional radiotherapy (CRT). Pooled dental plaque samples were collected during the radiation treatment from patients receiving IMRT (n = 13) and CRT (n = 12). Denaturing gradient gel electrophoresis (DGGE) was used to analyze the temporal variation of these plaque samples. The stimulated and unstimulated salivary flow rates were also compared between IMRT and CRT patients. Reductions in the severity of hyposalivation were observed in IMRT patients compared with CRT patients. We also observed that the temporal stability of the oral ecosystem was significantly higher in the IMRT group (69.96 ± 7.82%) than in the CRT group (51.98 ± 10.45%) (P < 0.05). The findings of the present study suggest that IMRT is more conducive to maintaining the relative stability of the oral ecosystem than CRT.


Assuntos
Boca/microbiologia , Boca/efeitos da radiação , Radioterapia de Intensidade Modulada/efeitos adversos , Placa Dentária/microbiologia , Neoplasias de Cabeça e Pescoço/radioterapia , Humanos , Metagenoma/genética , Metagenoma/efeitos da radiação , RNA Ribossômico 16S/genética , RNA Ribossômico 16S/isolamento & purificação , Xerostomia/etiologia , Xerostomia/prevenção & controle
4.
Shanghai Kou Qiang Yi Xue ; 19(1): 81-5, 2010 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-20300700

RESUMO

PURPOSE: To investigate the effect of nifedipine(NIF) on transcription of bcl-2 in human gingival epithelial cells(HGECs) in vitro and to study the pathogenesis of epithelial thickening in drug-induced gingival overgrowth(DGO). METHODS: The gingival tissues obtained from periodontal surgeries were digested with enzyme and HGECs were cultured in vitro; HGECs were identified by immunohistochemistry; bcl-2 mRNA levels were quantitated by Real-time PCR 24 hours and 48 hours after cells stimulated by NIF with different concentration (0microg/ml, 1microg/ml,2microg/ml,3microg/ml), in which 0microg/ml NIF as blank control. The data was analyzed by one-way ANOVA using SPSS 11.0 software package. RESULTS: HGECs cultured in vitro showed keratin positive signal and vimentin negative signal; the level of bcl-2 mRNA increased with NIF 3microg/ml after 24 hours treatment, which appeared significant increase compared with blank control (P<0.05); after 48 hours treatment the level of bcl-2 mRNA in the groups of 2microg/ml and 3microg/ml showed significant increase compared with blank control (P<0.05). CONCLUSION: NIF regulates the level of bcl-2 mRNA.


Assuntos
Gengiva , Nifedipino , Células Epiteliais , Humanos , Técnicas In Vitro , RNA Mensageiro
5.
J Periodontol ; 79(7): 1192-9, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18597601

RESUMO

BACKGROUND: Current epidemiologic data suggest that a localized infection (periodontitis) can disseminate into the distant tissues, and subgingival bacteria can migrate in the bloodstream, thereby contributing to independent systemic disease processes. To test this hypothesis, we investigated the effect of repeated systemic inoculations with Porphyromonas gingivalis (Pg) on intimal hyperplasia in iliac arteries in a rabbit model of balloon injury. METHODS: One week after single balloon injury to the iliac artery, 30 male New Zealand rabbits were randomly assigned to intravenous inoculation with 100 microl live Pg (10(7) colony-forming units; n = 15) or vehicle (n = 15) once weekly for 4, 8, or 12 consecutive weeks. Arteries were fixed by perfusion and removed for analysis of neointimal lesion formation. We measured intimal and medial lesion areas in iliac artery cross-sections as well as the intimal/medial ratio (I/M). We also analyzed Pg 16S ribosomal DNA amplification with polymerase chain reaction, systemic proinflammatory mediators with enzyme-linked immunosorbent assay, and immunolocalization of macrophages in the balloon-injured arteries. RESULTS: At 12 weeks, iliac intimal hyperplasia was accelerated, and I/M was significantly increased in Pg-inoculated animals (I/M 3.961 +/- 0.536 in the Pg group versus 3.585 +/- 0.353 in the control animals; P <0.01). Pg-inoculated animals also had significant increases in macrophage infiltration at 12 weeks, C-reactive protein levels at all time points, and interleukin-6 levels at 12 weeks. Moreover, Pg ribosomal DNA was found in the injured arteries of Pg-inoculated animals, but only after 12 weeks. CONCLUSION: Long-term systemic challenge with Pg, an oral pathogen, may accelerate intimal hyperplasia in balloon-injured iliac arteries.


Assuntos
Infecções por Bacteroidaceae/fisiopatologia , Cateterismo/efeitos adversos , Artéria Ilíaca/lesões , Porphyromonas gingivalis/fisiologia , Túnica Íntima/lesões , Animais , Infecções por Bacteroidaceae/microbiologia , Proteína C-Reativa/análise , DNA Bacteriano/análise , DNA Ribossômico/análise , Modelos Animais de Doenças , Hiperplasia , Artéria Ilíaca/microbiologia , Artéria Ilíaca/patologia , Mediadores da Inflamação/análise , Interleucina-6/análise , Macrófagos/patologia , Masculino , RNA Ribossômico 16S/análise , Coelhos , Distribuição Aleatória , Fatores de Tempo , Túnica Íntima/microbiologia , Túnica Íntima/patologia , Túnica Média/patologia
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