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1.
Oncologist ; 28(11): e1005-e1016, 2023 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-37310796

RESUMO

BACKGROUND: Patients with gastrointestinal cancer (GICA) are at high risk for venous thromboembolism (VTE). Data from randomized clinical trials in cancer-associated VTE suggest that direct oral anticoagulants (DOACs) conferred similar or superior efficacy but a heterogeneous safety profile in patients with GICA. We compared the safety and effectiveness of DOACs in patients with GICA and VTE at MD Anderson Cancer Center. MATERIALS AND METHODS: This was a retrospective chart review of patients with GICA and VTE receiving treatment with DOACs for a minimum of 6 months. Primary outcomes were the proportion of patients experiencing major bleeding (MB), clinically relevant non-major bleeding (CRNMB), and recurrent VTE. Secondary outcomes were time to bleeding and recurrent VTE. RESULTS: A cohort of 433 patients with GICA who were prescribed apixaban (n = 300), or rivaroxaban (n = 133) were included. MB occurred in 3.7% (95% confidence interval [CI] 2.1-5.9), CRNMB in 5.3% (95% CI 3.4-7.9), and recurrent VTE in 7.4% (95% CI 5.1-10.3). The cumulative incidence rates of CRNMB and recurrent VTE were not significantly different when comparing apixaban to rivaroxaban. CONCLUSION: Apixaban and rivaroxaban had a similar risk of recurrent VTE and bleeding and could be considered as anticoagulant options in selected patients with GICA and VTE.


Assuntos
Neoplasias Gastrointestinais , Tromboembolia Venosa , Humanos , Rivaroxabana/efeitos adversos , Tromboembolia Venosa/etiologia , Estudos Retrospectivos , Recidiva Local de Neoplasia/tratamento farmacológico , Anticoagulantes , Hemorragia/induzido quimicamente , Hemorragia/complicações , Hemorragia/tratamento farmacológico , Neoplasias Gastrointestinais/tratamento farmacológico , Administração Oral
2.
JCO Clin Cancer Inform ; 5: 789-804, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34351787

RESUMO

PURPOSE: Metastatic breast cancer (MBC) has a heterogeneous clinical course. We sought to develop a prognostic model for overall survival (OS) that incorporated contemporary tumor and clinical factors for estimating individual prognosis. METHODS: We identified patients with MBC from our institution diagnosed between 1998 and 2017. We developed OS prognostic models by Cox regression using demographic, tumor, and treatment variables. We assessed model predictive accuracy and estimated annual OS probabilities. We evaluated model discrimination and prediction calibration using an external validation data set from the National Comprehensive Cancer Network. RESULTS: We identified 10,655 patients. A model using age at diagnosis, race or ethnicity, hormone receptor and human epidermal growth factor receptor 2 subtype, de novo versus recurrent MBC categorized by metastasis-free interval, Karnofsky performance status, organ involvement, frontline biotherapy, frontline hormone therapy, and the interaction between variables significantly improved predictive accuracy (C-index, 0.731; 95% CI, 0.724 to 0.739) compared with a model with only hormone receptor and human epidermal growth factor receptor 2 status (C-index, 0.617; 95% CI, 0.609 to 0.626). The extended Cox regression model consisting of six independent models, for < 3, 3-14, 14-20, 20-33, 33-61, and ≥ 61 months, estimated up to 5 years of annual OS probabilities. The selected multifactor model had good discriminative ability but suboptimal calibration in the group of 2,334 National Comprehensive Cancer Network patients. A recalibration model that replaced the baseline survival function with the average of those from the training and validation data improved predictions across both data sets. CONCLUSION: We have generated and validated a robust prognostic OS model for MBC. This model can be used in clinical decision making and stratification in clinical trials.


Assuntos
Neoplasias da Mama , Neoplasias da Mama/diagnóstico , Feminino , Humanos , Recidiva Local de Neoplasia , Prognóstico , Modelos de Riscos Proporcionais
3.
NPJ Breast Cancer ; 6: 11, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32219153

RESUMO

We developed prognostic models for breast cancer-specific survival (BCSS) that consider anatomic stage and other important determinants of prognosis and survival in breast cancer, such as age, grade, and receptor-based subtypes with the intention to demonstrate that these factors, conditional on stage, improve prediction of BCSS. A total of 20,928 patients with stage I-III invasive primary breast cancer treated at The University of Texas MD Anderson Cancer Center between 1990 and 2016, who received surgery as an initial treatment were identified to generate prognostic models by Fine-Gray competing risk regression model. Model predictive accuracy was assessed using Harrell's C-index. The Aalen-Johansen estimator and a selected Fine-Gray model were used to estimate the 5-year and 10-year BCSS probabilities. The performance of the selected model was evaluated by assessing discrimination and prediction calibration in an external validation dataset of 29,727 patients from the National Comprehensive Cancer Network (NCCN). The inclusion of age, grade, and receptor-based subtype in addition to stage significantly improved the model predictive accuracy (C-index: 0.774 (95% CI 0.755-0.794) vs. 0.692 for stage alone, p < 0.0001). Young age (<40), higher grade, and TNBC subtype were significantly associated with worse BCSS. The selected model showed good discriminative ability but poor calibration when applied to the validation data. After recalibration, the predictions showed good calibration in the training and validation data. More refined BCSS prediction is possible through a model that has been externally validated and includes clinical and biological factors.

4.
Am J Hosp Palliat Care ; 37(9): 707-715, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31986903

RESUMO

INTRODUCTION: In patients with advanced cancer, prolongation of life with treatment often incurs substantial emotional and financial expense. Among hospitalized patients with cancer since acute kidney injury (AKI) is known to be associated with much higher odds for hospital mortality, we investigated whether renal replacement therapy (RRT) use in the intensive care unit (ICU) was a significant independent predictor of worse outcomes. METHODS: We retrospectively reviewed patients admitted in 2005 to 2014 who were diagnosed with stage IV solid tumors, had AKI, and a nephrology consult. The main outcomes were survival times from the landmark time points, inpatient mortality, and longer term survival after hospital discharge. Logistic regression and Cox proportional regression were used to compare inpatient mortality and longer term survival between RRT and non-RRT groups. Propensity score-matched landmark survival analyses were performed with 2 landmark time points chosen at day 2 and at day 7 from ICU admission. RESULTS: Of the 465 patients with stage IV cancer admitted to the ICU with AKI, 176 needed RRT. In the multivariate logistic regression model after adjusting for baseline serum albumin and baseline maximum Sequential Organ Failure Assessment (SOFA), the patients who received RRT were not significantly different from non-RRT patients in inpatient mortality (odds ratio: 1.004 [95% confidence interval: 0.598-1.684], P = .9892). In total, 189 patients were evaluated for the impact of RRT on long-term survival and concluded that RRT was not significantly associated with long-term survival after discharge for patients who discharged alive. Landmark analyses at day 2 and day 7 confirmed the same findings. CONCLUSIONS: Our study found that receiving RRT in the ICU was not significantly associated with inpatient mortality, survival times from the landmark time points, and long-term survival after discharge for patients with stage IV cancer with AKI.


Assuntos
Injúria Renal Aguda/epidemiologia , Injúria Renal Aguda/terapia , Neoplasias/epidemiologia , Terapia de Substituição Renal/estatística & dados numéricos , Injúria Renal Aguda/mortalidade , Idoso , Institutos de Câncer/estatística & dados numéricos , Feminino , Mortalidade Hospitalar , Humanos , Unidades de Terapia Intensiva/estatística & dados numéricos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasias/mortalidade , Neoplasias/patologia , Escores de Disfunção Orgânica , Estudos Retrospectivos , Análise de Sobrevida
5.
BMJ Open ; 7(3): e013242, 2017 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-28249848

RESUMO

OBJECTIVES: We appraised the methodological and reporting quality of randomised controlled clinical trials (RCTs) evaluating the efficacy and safety of Chinese herbal medicine (CHM) in patients with rheumatoid arthritis (RA). DESIGN: For this systematic review, electronic databases were searched from inception until June 2015. The search was limited to humans and non-case report studies, but was not limited by language, year of publication or type of publication. Two independent reviewers selected RCTs, evaluating CHM in RA (herbals and decoctions). Descriptive statistics were used to report on risk of bias and their adherence to reporting standards. Multivariable logistic regression analysis was performed to determine study characteristics associated with high or unclear risk of bias. RESULTS: Out of 2342 unique citations, we selected 119 RCTs including 18 919 patients: 10 108 patients received CHM alone and 6550 received one of 11 treatment combinations. A high risk of bias was observed across all domains: 21% had a high risk for selection bias (11% from sequence generation and 30% from allocation concealment), 85% for performance bias, 89% for detection bias, 4% for attrition bias and 40% for reporting bias. In multivariable analysis, fewer authors were associated with selection bias (allocation concealment), performance bias and attrition bias, and earlier year of publication and funding source not reported or disclosed were associated with selection bias (sequence generation). Studies published in non-English language were associated with reporting bias. Poor adherence to recommended reporting standards (<60% of the studies not providing sufficient information) was observed in 11 of the 23 sections evaluated. LIMITATIONS: Study quality and data extraction were performed by one reviewer and cross-checked by a second reviewer. Translation to English was performed by one reviewer in 85% of the included studies. CONCLUSIONS: Studies evaluating CHM often fail to meet expected methodological criteria, and high-quality evidence is lacking.


Assuntos
Artrite Reumatoide/tratamento farmacológico , Terapias Complementares/métodos , Medicamentos de Ervas Chinesas/uso terapêutico , Projetos de Pesquisa/normas , Viés , Fidelidade a Diretrizes , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Viés de Seleção , Resultado do Tratamento
6.
Food Chem ; 220: 306-312, 2017 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-27855904

RESUMO

Oxidation products and tocol homologues were monitored in oils during chicken frying to determine the discarding point of highly used frying oils. Oils were heated without chicken for 170h while chicken frying was performed 130 cycles at 180°C. As heating time and frying cycles increased, all oxidation parameters including acid value, total polar materials (TPM), conjugated dienoic acid (CDA), and p-anisidine values (p-AV) increased significantly (p<0.05). γ-Tocopherol and γ-tocotrienol had the lowest stability in oils during heating or frying processes compared to other tocol homologues. TPM values over 24% were obtained after about 109h for heated oil and 100 cycles for oils used to fry chicken. A decrease of 2,2-diphenyl-1-picrylhydrazyl (DPPH) in isooctane and methanol was highly correlated with the formation of TPM in oils during the frying process. Both DPPH loss and TPM values could be applied to determine the discarding points of highly used frying oils.


Assuntos
Ácidos/química , Antioxidantes/química , Culinária , Óleos de Plantas/química , Compostos de Anilina/análise , Animais , Compostos de Bifenilo/análise , Galinhas , Cromanos/análise , Temperatura Alta , Oxirredução , Picratos/análise , Aves Domésticas , Vitamina E/análogos & derivados , Vitamina E/análise , gama-Tocoferol/análise
7.
J Food Sci ; 81(8): C1914-20, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27387389

RESUMO

Eight phenolic compounds including: p-coumaric acid, vanillic acid, caffeic acid, chlorogenic acid, trolox, quercetin, curcumin, and resveratrol were treated with riboflavin (RF) photosensitization and in vitro antioxidant capacities of the mixtures were determined by 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2' azino bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS), and ferric reducing antioxidant power (FRAP) assays. Mixtures containing p-coumaric acid and vanillic acid under RF photosensitization showed increases in ferric ion reducing ability and radical scavenging activity of DPPH, whereas mixtures of other compounds had decreases in both radical scavenging ability and ferric reducing antioxidant power. Hydroxycoumaric acid and conjugated hydroxycoumaric and coumaric acids were tentatively identified from RF photosensitized p-coumaric acid, whereas dimmers of vanillic acid were tentatively identified from RF photosensitized vanillic acid. RF photosensitization may be a useful method to enhance antioxidant properties like ferric ion reducing abilities of some selected phenolic compounds.


Assuntos
Antioxidantes/farmacologia , Luz , Fenóis/farmacologia , Extratos Vegetais/farmacologia , Riboflavina/química , Antioxidantes/química , Benzotiazóis/metabolismo , Compostos de Bifenilo/metabolismo , Ácidos Cafeicos/química , Ácidos Cafeicos/farmacologia , Ácido Clorogênico/química , Ácido Clorogênico/farmacologia , Cromanos/química , Cromanos/farmacologia , Ácidos Cumáricos/química , Ácidos Cumáricos/farmacologia , Curcumina/química , Curcumina/farmacologia , Estrutura Molecular , Oxirredução , Fenóis/química , Picratos/metabolismo , Extratos Vegetais/química , Propionatos , Quercetina/química , Quercetina/farmacologia , Resveratrol , Estilbenos/química , Estilbenos/farmacologia , Ácidos Sulfônicos/metabolismo , Ácido Vanílico/química , Ácido Vanílico/farmacologia
8.
Cancer ; 121(19): 3422-7, 2015 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-26280679

RESUMO

BACKGROUND: The 2015 National Comprehensive Cancer Network guidelines recommend that genetic counseling and germline BRCA mutation testing be offered to women under age 60 with triple-negative breast cancer (TNBC). As a result of the 2010 American Society of Clinical Oncology (ASCO)/College of American Pathologists (CAP) guidelines for breast cancer, patients with breast cancers that are estrogen receptor (ER) or progesterone receptor (PR) low-positive (1%-9% on immunohistochemistry) are no longer strictly considered to have TNBC and may not be referred for genetic counseling. However, the incidence of BRCA mutation in patients with hormone receptor (HR) low-positive breast cancers remains unknown, and current ASCO/CAP guidelines may result in undertesting for BRCA mutations. METHODS: A prospectively maintained research database of breast cancer patients evaluated at The University of Texas MD Anderson Cancer Center between 2004 and 2014 was reviewed; 314 patients were identified with HER2/neu-negative breast cancers expressing ER and PR <10% with known BRCA mutation status. RESULTS: Three hundred fourteen patients had breast cancers expressing ER and PR <10%; 238 (75.8%) had HR-negative cancers (<1% ER and PR), and 76 (24.2%) had HR-low-positive cancers (1%-9% ER and/or PR). Among patients with HR-negative tumors, 86 of 238 (36.1%) had a BRCA1/2 mutation, whereas in the HR-low-positive group, 30 of 76 (39.5%) had a BRCA1/2 mutation. In multivariate analysis, HR status (<1% vs 1%-9%) was not significantly associated with BRCA1/2 mutations. CONCLUSIONS: The incidence of BRCA1/2 mutations is similar in patients with HR-low-positive breast cancer and patients with HR-negative breast cancer. Genetic counseling and BRCA testing should be offered to patients under age 60 who have HR-low-positive breast cancers. Cancer 2015;121:3435-43. © 2015 American Cancer Society.


Assuntos
Neoplasias da Mama/genética , Receptor ErbB-2/genética , Adulto , Neoplasias da Mama/patologia , Estudos de Coortes , Feminino , Genes BRCA2 , Aconselhamento Genético , Mutação em Linhagem Germinativa , Humanos , Incidência , Estudos Prospectivos
9.
J Womens Health (Larchmt) ; 21(4): 379-87, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22303820

RESUMO

BACKGROUND: Evidence-based guidelines for use of aspirin to decrease cardiovascular disease (CVD) events in women are well established. Despite this, aspirin is underused in women. We examined self-reported aspirin use in women for primary and secondary prevention of CVD events, correlates of use, and change in use over time from 2004 to 2009. METHODS: Data from volunteer respondents participating in a web-based CVD risk assessment tool at 127 US healthcare centers were analyzed. Survey questions included information on CVD risk factors, the presence or absence of any form of CVD, diabetes mellitus, and medication usage, including daily aspirin. Logistic regression analyses identified factors associated with aspirin intake. RESULTS: Of the 217,987 women respondents, 29,701 women were recommended to take aspirin based on the guidelines. We found, however, that only 41% of women who meet criteria for primary prevention and 48% of women who meet criteria for secondary prevention report that they take aspirin on a daily basis. The main factors that favored aspirin use were a family history of CVD or high cholesterol. Although aspirin use for secondary prevention did not change between the years 2004 and 2009, there was a significant increase in aspirin use for primary prevention. CONCLUSIONS: These findings confirm that the majority of women for whom aspirin is recommended for primary and secondary prevention of CVD were not following national guidelines. Educational programs for clinicians and women aimed at promoting appropriate use of aspirin is one measure that should improve CVD outcomes in women.


Assuntos
Aspirina/uso terapêutico , Doenças Cardiovasculares/prevenção & controle , Adulto , Feminino , Inquéritos Epidemiológicos , Humanos , Masculino , Pessoa de Meia-Idade , Programas Nacionais de Saúde , Razão de Chances , Relações Médico-Paciente , Medição de Risco , Estados Unidos
10.
J Surg Educ ; 68(3): 172-7, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21481799

RESUMO

OBJECTIVE: The overall objective of this study is to assess the usefulness of a standardized patient (SP) educational activity in the evaluation of surgery residents' communication skills. DESIGN: This is a pre/post observational study on surgery residents' communication skills, attitudes, and self-perceptions after an educational activity with standardized patients. SETTING: Scott & White Healthcare is a Central Texas-based non-profit integrated healthcare system with more than nine hospitals, 60 clinics, and a health plan. Scott & White Memorial Hospital in Temple is a Level-1 Trauma Center and the clinical site for the Texas A&M Health Science Center-College of Medicine in Temple, Texas. PARTICIPANTS: In all, 14 residents of the Texas A&M Health Science Center-College of Medicine/Scott & White General Surgery Residency Program participated in the SP education activity. RESULTS: After the activity, residents agreed more with the statements: "Communication skills are a learned behavior" and "Effective communication with patients is more difficult in high-stress situations." A significant increase in positive attitude toward physician-patient communication was measured in PGY3 and PGY-4 residents after the activity. However, there was no significant difference in residents' self-perceptions of communication skills after the activity. The residents believed the activity was somewhat useful, and feedback from the SPs was informative and helpful. CONCLUSIONS: Overall, in a formative setting, the SP methodology was a useful methodology to assess surgery residents' patient communication. The use of this methodology might require specific curriculum integration that is appropriate to the year of postgraduate training. This study demonstrates how SPs can be integrated into a Surgery Residency curriculum for teaching and assessing communication.


Assuntos
Comunicação , Cirurgia Geral/educação , Internato e Residência , Simulação de Paciente , Relações Médico-Paciente , Atitude do Pessoal de Saúde , Feminino , Humanos , Masculino , Autoimagem , Inquéritos e Questionários
11.
Surg Obes Relat Dis ; 7(2): 134-9, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21195676

RESUMO

BACKGROUND: The reported prevalence of anemia after malabsorptive bariatric surgery has varied from 5% to 64% in the post-Roux-en-Y gastric bypass (RYGB) population, owing to the small study sample sizes and generally poor follow-up in surgical referral practices. The present study estimated the prevalence of anemia in the post-RYGB population and determined whether an integrated healthcare system with a shared electronic medical record could improve postoperative follow-up. METHODS: The medical records from 1009 sequential patients who had undergone RYGB from 2000 to 2005 were retrospectively analyzed. All anemia data within the healthcare system's electronic medical record were accessible. RESULTS: Of the 1009 medical records, 720 contained ≥1 year of follow-up data concerning anemia. Anemia had developed or worsened in 259 patients, for a prevalence of 36% in the present sample. The anemia was moderate to severe (hemoglobin <10 g/dL) in 88 patients (12.2%.), many of whom subsequently required parenteral iron. Of the 1009 patients, the follow-up data for ≥3 years concerning anemia were available for only 357 patients (35.4%). CONCLUSION: The results of the present study have shown that in a large population of patients undergoing RYGB, the prevalence of anemia was great enough to justify more intensive long-term screening. We hope the findings from the present report influence the national screening standards for this patient population.


Assuntos
Anemia/epidemiologia , Derivação Gástrica/efeitos adversos , Obesidade Mórbida/cirurgia , Adulto , Idoso , Anemia/sangue , Anemia/etiologia , Feminino , Seguimentos , Hemoglobinas/metabolismo , Registros Hospitalares , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Prognóstico , Estudos Retrospectivos , Texas/epidemiologia , Fatores de Tempo , Adulto Jovem
12.
J Ethnopharmacol ; 112(3): 419-25, 2007 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-17543483

RESUMO

Polygonum cuspidatum (Polygonaceae) has traditionally been used in folk medicine to control oral diseases. Nevertheless, there are no reports related to its possible effect on the diseases, particularly on biofilm-related diseases such as dental caries. In this study, we evaluated in vitro effects of a fraction separated from Polygonum cuspidatum root on the viability, in both suspension and biofilms, and the biofilm formation of mutans streptococci. The separated fraction (F1) showed bacteriostatic and bactericidal activity against mutans streptococci in suspension, with minimum inhibitory concentration (MIC) range of 31.3-250 microg/ml and minimum bactericidal concentration (MBC) range of 0.5-1 mg/ml. At a concentration of 1.5 mg/ml, F1 killed approximately 2 log(10)CFU/ml of Streptococcus mutans and Streptococcus sobrinus after 2h of exposure. In biofilms, F1 also inhibited the viability of Streptococcus mutans and Streptococcus sobrinus, dependent on the biofilm age, the concentration of F1, and the treatment time. Four hours of exposure to 1.5 mg/ml F1 reduced the viable counts of Streptococcus mutans and Streptococcus sobrinus by greater than 2 log(10)CFU/disc. Furthermore, at sub-MIC levels, F1 inhibited biofilm formation by Streptococcus mutans and Streptococcus sobrinus in a dose-dependent fashion. Based on the preliminary phytochemical analysis, the activity of F1 may be related to the presence of anthraquinones, cardiac glycosides, terpenoids, and phenolics. These results indicate that F1 is probably useful in the control of oral biofilms and subsequent dental caries development.


Assuntos
Biofilmes/efeitos dos fármacos , Fallopia japonica/química , Extratos Vegetais/farmacologia , Raízes de Plantas/química , Streptococcus mutans/efeitos dos fármacos , Acetatos , Análise de Variância , Biofilmes/crescimento & desenvolvimento , Cromatografia em Camada Fina , Relação Dose-Resposta a Droga , Metanol , Testes de Sensibilidade Microbiana , Viabilidade Microbiana/efeitos dos fármacos , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Streptococcus mutans/crescimento & desenvolvimento , Streptococcus sobrinus/efeitos dos fármacos , Streptococcus sobrinus/crescimento & desenvolvimento , Fatores de Tempo
13.
Arch Oral Biol ; 51(12): 1131-40, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16914113

RESUMO

OBJECTIVES: Polygonum cuspidatum has been used in Korean folk medicine to improve oral hygiene. This study was performed to evaluate the effects of methanol extract from root of P. cuspidatum (MEP) on bacterial viability and the virulence factors of Streptococcus mutans and Streptococcus sobrinus. METHODS: To test the effects of MEP on bacterial viability, we determined the minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) against 20 bacterial strains, including S. mutans and S. sobrinus, using a micro-dilution assay. In case of S. mutans and S. sobrinus, the assays for time-kill and bacterial growth rate at sub-MIC concentrations were also performed. To determine effects of the extract on the virulence factors of S. mutans and S. sobrinus, the assays for sucrose-dependent adherence, water-insoluble glucan formation, glycolytic acid production, and acid tolerance were performed at sub-MIC levels. Phytochemical analysis for constituents of MEP was carried out. RESULTS: MEP showed a broad antibacterial range (MIC 0.5-4 mg/ml). The MBC was two to four times higher than the MIC. The time-kill curves showed S. mutans and S. sobrinus were significantly killed after 1h of incubation. At sub-MIC levels, doubling times of S. mutans and S. sobrinus dose-dependently increased up to 211% and 123%, respectively. At sub-MIC levels, MEP also showed inhibitory effects on the virulence factors of S. mutans and S. sobrinus in a dose-dependent fashion. Phytochemical analysis revealed the presence of alkaloids, sterol/terpenes, tannins, flavonoids, and carbohydrates. CONCLUSION: These data indicate that MEP has inhibitory effects on bacterial viability at higher concentrations (> or =MIC) and the virulence factors of S. mutans and S. sobrinus at sub-MIC concentrations, suggesting that it might be useful for the control of dental plaque formation and subsequent dental caries formation.


Assuntos
Antibacterianos/farmacologia , Fallopia japonica/química , Metanol/farmacologia , Raízes de Plantas/química , Streptococcus/efeitos dos fármacos , Antibacterianos/química , Aderência Bacteriana/efeitos dos fármacos , Contagem de Colônia Microbiana , Cárie Dentária/microbiologia , Cárie Dentária/prevenção & controle , Glucanos/biossíntese , Glucosiltransferases/metabolismo , Glicólise/efeitos dos fármacos , Metanol/química , Testes de Sensibilidade Microbiana/métodos , Viabilidade Microbiana/efeitos dos fármacos , Extratos Vegetais/farmacologia , Streptococcus/patogenicidade , Streptococcus/fisiologia , Streptococcus mutans/efeitos dos fármacos , Streptococcus mutans/fisiologia , Streptococcus sobrinus/efeitos dos fármacos , Streptococcus sobrinus/fisiologia , Virulência/efeitos dos fármacos
14.
Arch Pharm Res ; 29(6): 490-6, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16833017

RESUMO

This study aimed to evaluate in vitro effects of Rheum undulatum L. root on the development of dental caries, especially its effects on viability, dental plaque formation, and glycolytic acid production of Streptococcus mutans and Streptococcus sobrinus. Methanol extract of Rheum undulatum L. root and its fractions were prepared and tested. Among the test extract and fractions, dichloromethane fraction (DF) showed the most active antibacterial activity (inhibition zone: 13-17 mm) against S. mutans and S. sobrinus in a disc diffusion method. Minimal inhibitory concentrations (MICs) of DF against these bacteria ranged from 0.25 to 0.5 mg/mL. Furthermore, DF significantly inhibited the caries-inducing factors of these bacteria. At sub-MIC levels, DF inhibited in vitro dental plaque formation by S. mutans and S. sobrinus (IC50= 0.079 and 0.142 mg/mL, respectively), which was caused, in part, by the inhibitory effect on the activity of glucosyltransferases. A significant reduction of glycolytic acid production was found at the concentration as low as 0.032 mg/mL for S. mutans and 0.063 mg/mL for S. sobrinus. The possible bioactive compounds that are inducing in vitro anti-cariogenic activity of DF are unknown. Based on the preliminary phytochemical analysis, the activity of DF may be related to the presence of anthraquinones, cardiac glycosides, coumarines, sterols/terpenes, and phenolics. These results indicate that DF is probably useful for the control of dental plaque formation and subsequent dental caries development.


Assuntos
Antibacterianos/farmacologia , Cariostáticos/farmacologia , Placa Dentária/prevenção & controle , Extratos Vegetais/farmacologia , Rheum , Streptococcus mutans/efeitos dos fármacos , Streptococcus sobrinus/efeitos dos fármacos , Antibacterianos/química , Cariostáticos/química , Cárie Dentária/metabolismo , Cárie Dentária/microbiologia , Cárie Dentária/prevenção & controle , Placa Dentária/metabolismo , Placa Dentária/microbiologia , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Glucanos/metabolismo , Glucosiltransferases/antagonistas & inibidores , Glucosiltransferases/metabolismo , Concentração de Íons de Hidrogênio , Cloreto de Metileno/química , Testes de Sensibilidade Microbiana , Extratos Vegetais/química , Raízes de Plantas , Solventes/química , Streptococcus mutans/enzimologia , Streptococcus mutans/crescimento & desenvolvimento , Streptococcus sobrinus/enzimologia , Streptococcus sobrinus/crescimento & desenvolvimento
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