91 research outputs found
Detecção de patógenos de lesões periodontais
OBJETIVO: Realizar a detecção comparativa de A. actinomycetemcomitans e F. nucleatum de sĂtios periodontais e sadios. MÉTODOS: Foram analisadas amostras subgengivais de 50 pacientes com periodontite do adulto e de 50 indivĂduos sadios. Ambos os organismos foram isolados em meio ágar de soja tripticaseĂna-bacitracina-vancomicina e detectados por PCR. Testes bioquĂmicos convencionais foram usados para a identificação bacteriana. RESULTADOS: A. actinomycetemcomitans e F. nucleatum foram isolados em 18 e 20% dos pacientes, respectivamente, e em 2 e 24% dos indivĂduos sadios. Entre os isolados de A. actinomycetemcomitans, o biĂłtipo II foi o mais prevalente. O par de iniciadores AA mostrou 100% de sensibilidade na detecção de A. actinomycetemcomitans, em ambos os grupos de indivĂduos. Iniciadores ASH e FU foram tambĂ©m 100% sensĂveis para detectar esse organismo em amostras de indivĂduos sadios. O iniciador FN5047 foi mais sensĂvel para detectar F. nucleatum em amostras de pacientes ou de sadios que o 5059S. Iniciadores ASH e 5059S foram mais especĂficos na detecção de A. actinomycetemcomitans e F. nucleatum, respectivamente, em amostras de pacientes e de sadios. CONCLUSĂ•ES: PCR constitui-se uma ferramenta efetiva na detecção de patĂłgenos periodontais de espĂ©cimes clĂnicos, fornecendo um diagnĂłstico rápido e seguro da doença periodontal. Entretanto, esse mĂ©todo depende da escolha dos iniciadores especĂficos utilizados.OBJECTIVE: To comparatively detect A. actinomycetemcomitans and F. nucleatum from periodontal and healthy sites. METHODS: Subgingival clinical samples from 50 periodontitis adult patients and 50 healthy subjects were analyzed. Both organisms were isolated using a trypticase soy agar-bacitracin-vancomycin (TSBV) medium and detected by PCR. Conventional biochemical tests were used for bacteria identification. RESULTS: A. actinomycetemcomitans and F. nucleatum were isolated in 18% and 20% of the patients, respectively, and in 2% and 24% of healthy subjects. Among A. actinomycetemcomitans isolates, biotype II was the most prevalent. Primer pair AA was 100% sensitive in the detection of A. actinomycetemcomitans from both subject groups. Primers ASH and FU were also 100% sensitive to detect this organism in healthy subject samples. Primer pair FN5047 was more sensitive to detect F. nucleatum in patients or in healthy samples than primer 5059S. Primers ASH and 5059S were more specific in the detection of A. actinomycetemcomitans and F. nucleatum, respectively, in patients and in healthy subject samples. CONCLUSIONS: PCR is an effective tool for detecting periodontal pathogens in subgingival samples, providing a faster and safer diagnostic tool of periodontal diseases. The method's sensitivity and specificity is conditioned by the choice of the set of primers used
Prevotella intermedia and Porphyromonas gingivalis isolated from osseointegrated dental implants: colonization and antimicrobial susceptibility
Aggregatibacter actinomycetemcomitans and Fusobacterium nucleatum in subgingival biofilms from Brazilian patients with and without periodontal disease: comparison of two detection methods
Objetivo: Realizar la detecciĂłn comparativa de cepas de A. actinomycetemcomitans y F. nucleatum de muestras subgingivales por los mĂ©todos de cultivo y de reacciĂłn en cadena de la polimerasa (PCR). MĂ©todos: Fueron evaluados 50 pacientes con periodontitis crĂłnica (P) y 50 pacientes sanos (S). Las muestras fueron colectadas de bolsas periodontales y surcos gingivales. El cultivo bacteriano fue realizado en agar tripticasa de soya-suero de caballo-bacitracina-vancomicina, e incubado en anaerobiosis. La identificaciĂłn bacteriana fue por mĂ©todos bioquĂmicos de fermentaciĂłn de carbohidratos y por PCR. Resultados: Por el mĂ©todo de cultivo, de las 50 muestras de periodontitis, 9 (18%) fueron positivas para A. actinomycetemcomitans aislándose 17 cepas. TambiĂ©n, de esas muestras, 10 (20%) fueron positivas para F. nucleatum aislándose 19 cepas. De las 50 muestras de pacientes sanos, solamente 1 (2%) fue positiva para A. actinomycetemcomitans obteniĂ©ndose 2 cepas, y 12 (24%) positivas para F. nucleatum con 18 cepas. Por PCR fueron observadas diferencias en la detecciĂłn de A. actinomycetemcomitans, entre los tres pares de partidores utilizados, para muestras de bolsa periodontal y surco gingival: partidor AA, 96% y 86%; partidor FU, 48% y 42%; y partidor ASH, 24% y 6%. Los porcentajes de detecciĂłn para F. nucleatum de muestras de P y S fueron: partidor FN-5047, 36% y 18%; y partidor 505-S, 8% para ambas muestras colectadas. Cepas de A. actinomycetemcomitans biotipo II fueron las más prevalentes. Conclusiones: EL mĂ©todo de PCR fue más sensible y especĂfico en la detecciĂłn bacteriana que el cultivo.Objective: A comparative detection of strains of A. actinomycetemcomitans and F. nucleatum directly from subgingival samples was performed by culture and polymerase chain reaction (PCR) methods. Methods: Fifty patients with chronic periodontitis (P) and 50 healthy patients (S) were evaluated. Subgingival samples were collected from periodontal pockets and gingival sulcus. Bacterial culture was performed on trypticase soy-horse serum- bacitracin-vancomycin agar and incubated in anaerobiosis. Bacterial identification was done by biochemical methods of carbohydrate fermentation and by PCR. Results: By culture method, of the 50 samples of periodontitis, 9 (18%) were positive for A. actinomycetemcomitans isolating 17 strains. Also, of these samples, 10 (20%) were positive for F. nucleatum isolating 19 strains. Of the 50 samples from healthy patients, only 1 (2%) was positive for A. actinomycetemcomitans, obtaining 2 strains, and 12 (24%) positive for F. nucleatum with 18 strains. Differences were observed in the detection of A. actinomycetemcomitans among the three pairs of primers used, for periodontal pocket and gingival sulcus samples: primer AA, 96% and 86%; primer FU, 48% and 42%; and primer ASH, 24% and 6%. The percentages of detection for F. nucleatum of samples from P and S were: primer FN-5047, 36% and 18%; and primer 505-S, 8% for both samples collected. Strains of A. actinomycetemcomitans biotype II were the most prevalent. Conclusions: The PCR method was more sensitive and specific in the bacterial detection than the culture
Aderência de Actinobacillus actinomycetemcomitans às células epiteliais bucais: estabilidade e aspectos ultra-estruturais
Actinobacillus actinomycetemcomitans is considered an important pathogen in periodontal disease, especially in localized juvenile periodontitis. The bacterial mechanism of adherence to oral epithelial cells (OEC), teeth or other bacteria is the initial step in colonization and in the pathogenesis of oral infectious processes, such as gingivitis and periodontitis. The goal of this study was to evaluate the adherence and its variability, as well as ultrastructural aspects of A. actinomycetemcomitans isolates on OEC, when they were submitted to repeated subcultures. Twenty-one fresh isolates from 21 patients with periodontal disease and one reference strain were tested. All tested isolates adhered to OEC and repeated subcultures produced variations in the adhesion rates of each isolate. Furthermore, a direct correlation between high levels of adherence and the presence of large amounts of extracellular components, such as fimbriae, vesicles and extracellular amorfous material, was observed.Actinobacillus actinomycetemcomitans Ă© considerado um importante patĂłgeno na doença periodontal, particularmente na periodontite juvenil localizada. O mecanismo de adesĂŁo bacteriana Ă s cĂ©lulas epiteliais bucais (CEB), aos dentes e a outras bactĂ©rias, constitui-se o passo inicial na colonização e patogĂŞnese nos quadros de gengivite e periodontite. Neste estudo, avaliou-se a aderĂŞncia Ă s CEB, a sua variabilidade e os aspectos ultra-estruturais de 21 isolados e de uma cepa de referĂŞncia de A. actinomycetemcomitans, quando submetidos a repiques sucessivos. Todos os isolados testados aderiram Ă s CEB e os repiques sucessivos determinaram variações nas taxas de aderĂŞncia de cada isolado. Os isolados que apresentaram altos Ăndices de aderĂŞncia tambĂ©m produziram quantidades elevadas de componentes extracelulares, tais como fĂmbrias, vesĂculas e/ou material amorfo extracelular
Clostridium perfringens and necrotic enteritis in poultry: virulence, genetic and molecular factors
Clostridium perfringens é o causador da enterite necrótica que afeta a produção de frangos de corte no mundo todo. Essa bactéria produz diversas toxinas e causa lesões no intestino tendo como consequências a elevada mortalidade e perdas econômicas devido à baixa produtividade. Nessa revisão são apresentados os principais fatores de virulência, a susceptibilidade aos antimicrobianos e a diversidade genética de C. perfringens isolados de frangos com enterite necrótica.Clostridium perfringens cause necrotic enteritis affecting the poultry production worldwide. This bacterium produces various toxins and causes lesions in the intestine producing high mortality and economic loss due to the low productivity. In this review, the major virulence factors, antimicrobial susceptibility and genetic diversity of C. perfringens from chickens with necrotic enteritis are showed
Antimicrobial resistance and prevalence of resistance genes in intestinal Bacteroidales strains
OBJECTIVE: This study examined the antimicrobial resistance profile and the prevalence of resistance genes in Bacteroides spp. and Parabacteroides distasonis strains isolated from children's intestinal microbiota. METHODS: The susceptibility of these bacteria to 10 antimicrobials was determined using an agar dilution method. β-lactamase activity was assessed by hydrolysis of the chromogenic cephalosporin of 114 Bacteriodales strains isolated from the fecal samples of 39 children, and the presence of resistance genes was tested using a PCR assay. RESULTS: All strains were susceptible to imipenem and metronidazole. The following resistance rates were observed: amoxicillin (93%), amoxicillin/clavulanic acid (47.3%), ampicillin (96.4%), cephalexin (99%), cefoxitin (23%), penicillin (99%), clindamycin (34.2%) and tetracycline (53.5%). P-lactamase production was verified in 92% of the evaluated strains. The presence of the cfiA, cepA, ermF, tetQ and nim genes was observed in 62.3%, 76.3%, 27%, 79.8% and 7.8% of the strains, respectively. CONCLUSIONS: Our results indicate an increase in the resistance to several antibiotics in intestinal Bacteroides spp. and Parabacteroides distasonis and demonstrate that these microorganisms harbor antimicrobial resistance genes that may be transferred to other susceptible intestinal strains
Association between periodontal condition and subgingival microbiota in women during pregnancy: a longitudinal study
Objectivo In this study, the gingival conditions and the quantitative detection for Aggregatibacter actinomycetemcomitans, Fusobacterium nucleatum, Porphyromonas gingivalis and Prevotella intermedia in pregnant women were determined. Material and Methods Quantitative determinations of periodontal bacteria by using a SyBr green system in women during pregnancy were performed. Women at the 2nd and 3rd trimesters of pregnancy and non-pregnant women were included in this study. A. actinomycetemcomitans was observed in high numbers in women at the 2nd and 3rd trimesters of pregnancy with a significant difference (
Occurrence of Aggregatibacter actinomycetemcomitans in Brazilian indians from Umutina Reservation, Mato Grosso, Brazil
Aggregatibacter actinomycetemcomitans is associated with periodontal disease, especially localized aggressive periodontitis, produces a potent leukotoxin and its distribution is influenced by ethnic characteristics of the population. Objective: Using culture and polymerase chain reaction (PCR) techniques, this study evaluated the occurrence of this microorganism and the distribution of leukotoxic strains isolated from Indians belonging to the Umutima Reservation, Mato Grosso, Brazil. MATERIAL AND METHODS: Forty-eight native Brazilians with gingivitis and 38 with chronic periodontitis, belonging to Umutina, Paresi, Bororo, Bakairi, Kayabi, Irantxe, Nambikwara and Terena ethnicities, were studied. Subgingival, supragingival and saliva samples of each patient were collected and transferred to VMGA III medium and to ultra pure Milli Q water. Bacteria were grown on TSBV agar and incubated in anaerobiosis (90% N2 + 10% CO2) at 37ÂşC for 72 h. The presence of the ltx promoter was determined by PCR, and a 530 bp deletion in the promoter was evaluated by using specific primers. RESULTS: A. actinomycetemcomitans was isolated from 8.33% of saliva, supragingival and subgingival samples from patients with gingivitis and from 18.42% of saliva and supragingival biofilm, and 26.32% subgingival biofilm from patients with chronic periodontitis. By PCR, the bacterial DNA was detected in 8.33% of saliva, supragingival and subgingival biofilms from patients with gingivitis and from 23.68% of saliva, 28.95% supragingival biofilm and 34.21% subgingival biofilm from patients with periodontitis. All strains were grouped as non-JP2 clones based on the absence of deletion in the leukotoxin promoter. Differences among the microbial and clinical parameters in patients were analyzed by using the Mann-Whitney, Chi-square or Fisher's exact tests. CONCLUSIONS: The present results suggest that A. actinomycetemcomitans can be related to the attachment loss in this population, but the presence of minimally leukotoxic strains, as well as its role in the pathogenesis of the periodontitis in these native Brazilians need to be further investigated
Dose-Response Met-RANTES Treatment of Experimental Periodontitis: A Narrow Edge between the Disease Severity Attenuation and Infection Control
Chemokines and chemokine receptors have been implicated in the selective migration of leukocyte subsets to periodontal tissues, which consequently influences the disease outcome. Among these chemoattractants, the chemokines CCL3, CCL4 and CCL5 and its receptors, CCR1 and CCR5, have been associated with increased disease severity in mice and humans. Therefore, in this study we investigated the modulation of experimental periodontitis outcome by the treatment with a specific antagonist of CCR1 and 5 receptors, called met-RANTES. C57Bl/6 mice was orally infected with Aggregatibacter actinomycetemcomitans and treated with 0.05, 0.1, 0.5, 1.5 and 5 mg doses of met-RANTES on alternate days, and evaluated by morphometric, cellular, enzymatic and molecular methods. At 0.5 mg up to 5 mg doses, a strong reduction in the alveolar bone loss and inflammatory cell migration were observed. Interestingly, 5 mg dose treatment resulted in the maximum inhibition of inflammatory cell migration, but resulted in a similar inhibition of bone loss when compared with the lower doses, and also resulted in increased bacterial load and CRP response. When 0.5 and 5 mg therapy regimens were compared it was observed that both therapeutic protocols were able to downregulate the levels of pro-inflammatory, Th1-type and osteoclastogenic cytokines, and CD3+ and F4/80+ cells migration to periodontal tissues, but the high dose modulates host response in a more pronounced and unspecific and excessive way, interfering also with the production of antimicrobial mediators such as MPO, iNOS and IgG, and with GR1+ and CD19+ cells migration. Our results demonstrate a thin line between beneficial immunoregulation and impaired host defense during experimental periodontitis, and the determination of the exact equilibrium point is mandatory for the improvement of immune-targeted therapy of periodontitis
Evolving trends in the management of acute appendicitis during COVID-19 waves. The ACIE appy II study
Background: In 2020, ACIE Appy study showed that COVID-19 pandemic heavily affected the management of patients with acute appendicitis (AA) worldwide, with an increased rate of non-operative management (NOM) strategies and a trend toward open surgery due to concern of virus transmission by laparoscopy and controversial recommendations on this issue. The aim of this study was to survey again the same group of surgeons to assess if any difference in management attitudes of AA had occurred in the later stages of the outbreak.
Methods: From August 15 to September 30, 2021, an online questionnaire was sent to all 709 participants of the ACIE Appy study. The questionnaire included questions on personal protective equipment (PPE), local policies and screening for SARS-CoV-2 infection, NOM, surgical approach and disease presentations in 2021. The results were compared with the results from the previous study.
Results: A total of 476 answers were collected (response rate 67.1%). Screening policies were significatively improved with most patients screened regardless of symptoms (89.5% vs. 37.4%) with PCR and antigenic test as the preferred test (74.1% vs. 26.3%). More patients tested positive before surgery and commercial systems were the preferred ones to filter smoke plumes during laparoscopy. Laparoscopic appendicectomy was the first option in the treatment of AA, with a declined use of NOM.
Conclusion: Management of AA has improved in the last waves of pandemic. Increased evidence regarding SARS-COV-2 infection along with a timely healthcare systems response has been translated into tailored attitudes and a better care for patients with AA worldwide
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