RESUMO
The microbial diversity and functioning around oceanic islands is poorly described, despite its importance for ecosystem homeostasis. Here, we aimed to verify the occurrence of microbe-driven phenanthrene co-oxidation in the seawater surrounding the Trindade Island (Brazil). We also used Next-Generation Sequencing to evaluate the effects of aliphatic and polycyclic aromatic hydrocarbons (PAHs) on these microbial community assemblies. Microcosms containing seawater from the island enriched with either labelled (9-14C) or non-labelled phenanthrene together with hexadecane, weathered oil, fluoranthene or pyrene, and combinations of these compounds were incubated. Biodegradation of phenanthrene-9-14C was negatively affected in the presence of weathered oil and PAHs but increased in the presence of hexadecane. PAH contamination caused shifts in the seawater microbial community-from a highly diverse one dominated by Alphaproteobacteria to less diverse communities dominated by Gammaproteobacteria. Furthermore, the combination of PAHs exerted a compounded negative influence on the microbial community, reducing its diversity and thus functional capacity of the ecosystem. These results advance our understanding of bacterial community dynamics in response to contrasting qualities of hydrocarbon contamination. This understanding is fundamental in the application and monitoring of bioremediation strategies if accidents involving oil spillages occur near Trindade Island and similar ecosystems.
Assuntos
Bactérias/efeitos dos fármacos , Bactérias/metabolismo , Hidrocarbonetos/efeitos adversos , Consórcios Microbianos/efeitos dos fármacos , Consórcios Microbianos/fisiologia , Fenantrenos/metabolismo , Água do Mar/microbiologia , Alcanos , Alphaproteobacteria/efeitos dos fármacos , Alphaproteobacteria/metabolismo , Bactérias/classificação , Bactérias/genética , Biodegradação Ambiental , Biodiversidade , Brasil , DNA Bacteriano/genética , Ecossistema , Gammaproteobacteria/efeitos dos fármacos , Gammaproteobacteria/metabolismo , Sequenciamento de Nucleotídeos em Larga Escala , Ilhas , Metagenômica , Consórcios Microbianos/genética , Poluição por Petróleo/efeitos adversos , Hidrocarbonetos Policíclicos Aromáticos/farmacologia , Pirenos , RNA Ribossômico 16S/metabolismo , Poluentes da ÁguaRESUMO
INTRODUCTION: Nonalcoholic steatohepatitis (NASH) is characterized by the presence of steatosis, inflammation, and ballooning degeneration of hepatocytes, with or without fibrosis. The prevalence of NASH has increased with the obesity epidemic, but its etiology is multifactorial. The current studies suggest the role of gut microbiota in the development and progression of NASH. The aim is to review the studies that investigate the relationship between gut microbiota and NASH. These review also discusses the pathophysiological mechanisms and the influence of diet on the gut-liver axis. RESULT: The available literature has proposed mechanisms for an association between gut microbiota and NASH, such as: modification energy homeostasis, lipopolysaccharides (LPS)-endotoxemia, increased endogenous production of ethanol, and alteration in the metabolism of bile acid and choline. There is evidence to suggest that NASH patients have a higher prevalence of bacterial overgrowth in the small intestine and changes in the composition of the gut microbiota. However, there is still a controversy regarding the microbiome profile in this population. The abundance of Bacteroidetes phylum may be increased, decreased, or unaltered in NASH patients. There is an increase in the Escherichia and Bacteroides genus. There is depletion of certain taxa, such as Prevotella and Faecalibacterium. CONCLUSION: Although few studies have evaluated the composition of the gut microbiota in patients with NASH, it is observed that these individuals have a distinct gut microbiota, compared to the control groups, which explains, at least in part, the genesis and progression of the disease through multiple mechanisms. Modulation of the gut microbiota through diet control offers new challenges for future studies.
Assuntos
Disbiose/fisiopatologia , Medicina Baseada em Evidências , Microbioma Gastrointestinal , Fígado/fisiopatologia , Modelos Biológicos , Hepatopatia Gordurosa não Alcoólica/etiologia , Animais , Ácidos e Sais Biliares/metabolismo , Colina/metabolismo , Dieta/efeitos adversos , Progressão da Doença , Disbiose/imunologia , Disbiose/metabolismo , Disbiose/microbiologia , Endotoxemia/etiologia , Endotoxemia/imunologia , Endotoxemia/microbiologia , Endotoxemia/fisiopatologia , Ingestão de Energia , Metabolismo Energético , Etanol/metabolismo , Fermentação , Microbioma Gastrointestinal/imunologia , Humanos , Lipopolissacarídeos/biossíntese , Lipopolissacarídeos/toxicidade , Fígado/imunologia , Fígado/metabolismo , Hepatopatia Gordurosa não Alcoólica/imunologia , Hepatopatia Gordurosa não Alcoólica/microbiologia , Hepatopatia Gordurosa não Alcoólica/fisiopatologiaRESUMO
This research paper aimed to find endemic bacteria from the cattle production system to control the growth of mastitis pathogens. Bacteria were isolated from compost barn sawdust of two dairy cattle systems and later tested to verify their ability to control the growth of Staphylococcus aureus isolates obtained from cattle with mastitis. Bacterial isolates from these systems were tested to verify biocontrol capacity using the double-layer method. A total of 189 isolates were obtained from all samples by considering the morphology of the different bacterial colonies, with 30 isolates showing positive results for the growth control of at least one S. aureus strain and 19 isolates showing the ability to control more than one pathogen strain. The ability to control more than one pathogen and present a significant halo of inhibition in our isolates represents positive traits in the search for cattle mastitis biocontrol microorganisms. Thus, the results obtained represent the range of bacteria capable of controlling the pathogens without the use of antibiotics.
Assuntos
Doenças dos Bovinos , Mastite Bovina , Infecções Estafilocócicas , Feminino , Bovinos , Animais , Staphylococcus aureus/fisiologia , Bactérias , Infecções Estafilocócicas/veterinária , Antibacterianos/farmacologia , Mastite Bovina/microbiologia , Leite/microbiologia , Doenças dos Bovinos/microbiologiaRESUMO
LIMITATIONS: of bioaugmentation strategies are an obstacle for damage mitigation caused by oil spills in marine environments. Cells added to the contaminated sites are quickly lost by low adherence to the contaminants, rendering ineffective. This study used two hydrocarbonoclastic species - Rhodococcus rhodochrous TRN7 and Nocardia farcinica TRH1 cells - growing in mineral medium containing hexadecane to evaluate cell distribution in a crude-oil contaminated marine water. Cell affinity to hydrophobic compounds was quantified using Microbial Adhesion to Hydrocarbons test and analysis of fatty acids profile was performed using the Microbial Identification System. Bioremediation simulations were set up and cell populations of both strains were quantified by Fluorescent in situ Hybridization. R. rhodochrous and N. farcinica reached up to 97% and 60% of adhesion to hexadecane, respectively. The carbon source had more influence on the fatty acid profiles of both strains than the microbial species. The presence of 45.24% of 13:0 anteiso on total fatty acids in R. rhodochrous and 12.35% of saturated fatty acids with less than 13 carbons atoms in N. farcinica, as well as the occurrence of fatty alcohols only in presence of hexadecane in both species, are indicators that fatty acid changes are involved in the adaptation of the cells to remain at the water/oil interface. Cell quantification after bioremediation simulations revealed an increase in the density of both species, suggesting that the bioremediation strategies resulted on the increase of hydrocarbonoclastic species and up to 27.9% of all prokaryotic microbial populations in the microcosms were composed of R. rhodochrous or N. farcinica. These findings show the potential of application of these two bacterial strains in bioaugmentation of hydrocarbon-contaminated marine ecosystems.R. rhodochrous TRN7 and N. farcinica TRH1 hydrocarbonoclastic strains modify the fatty acid profile and increases density, optimizing hydrocarbons biodegradation.
Assuntos
Ecossistema , Petróleo , Alcanos , Biodegradação Ambiental , Hidrocarbonetos , Hibridização in Situ Fluorescente , Nocardia , RhodococcusRESUMO
Information about bacterial diversity, such as the number of each species in the root canals of primary teeth, contributes to improving our effective management of infections of endodontic origin in primary teeth. This study made a qualitative and quantitative assessment of the bacteria in the root canals of primary teeth with necrotic pulp, using the fluorescence in situ hybridization (FISH) technique. Thirty-one primary teeth with pulp necrosis from 31 children were evaluated using the FISH technique, to detect the presence and density of Aggregatibacter actinomycetemcomitans, Campylobacter rectus, Enterococcus faecalis, Fusobacterium nucleatum, Porphyromonas gingivalis, Prevotella intermedia, Prevotella nigrescens, Streptococcus, Streptococcus mutans, Streptococcus sobrinus, Tannerella forsythia and Treponema denticola. Descriptive measures explained the data related to density, and Student's t-test assessed the differences among the densities of each bacterium, according to signs and symptoms. The bacterial density was paired and correlated. All bacteria tested were detected and identified in all the samples. The average number of bacterial individuals from each species ranged from 1.9 x 108 cells/mL (S. mutans) to 3.1 x 108 cells/mL (F. nucleatum) (p > 0.05). The sum of the mean counts of each bacterium represented almost 80% of the entire microbial community. Patients with pain had significantly more T. denticola, and those with edema showed a greater density of Streptococcus and P. nigrescens (p < 0.05). This study revealed that all 12 bacteria evaluated were found in all primary teeth with pulp necrosis. There was no predominance among the species studied; all species had a similar number of individuals.
Assuntos
Cavidade Pulpar , Necrose da Polpa Dentária , Dente Decíduo , Criança , DNA Bacteriano , Humanos , Hibridização in Situ Fluorescente , Porphyromonas gingivalis , Prevotella intermediaRESUMO
OBJECTIVE: The aim of this study was to verify the effect of a beverage containing ora-pro-nobis (OPN) flour on intestinal microbiota, gastrointestinal symptoms, and anthropometric parameters in women. METHODS: This prospective, double-blinded, randomized clinical trial included 24 women volunteers. For 6 wk, the test group received a beverage supplemented with OPN, and the control group received the same beverage without OPN. Fecal microbiota were evaluated by the fluorescence in situ hybridization method. Each participant responded to a questionnaire based on the Gastrointestinal Symptom Rating Scale. The data were analyzed by Student's t test to compare the effects between treatments (P < 0.05). RESULTS: Supplementation with the OPN beverage reduced weight (P = 0.008), waist circumference (P = 0.010), and body fat (P = 0.000). Additionally, the treatment increased satiety (P = 0.039), reduced eructation (P = 0.038) and constipation (P = 0.017), and improved feces consistency (P = 0.017). CONCLUSION: The OPN flour beverage has an effect on weight reduction, body fat composition, and improvement in gastrointestinal symptoms. These results highlight the beneficial effects of ora-pro-nobis flour beverage against the development of obesity.
Assuntos
Composição Corporal , Farinha , Bebidas , Método Duplo-Cego , Fezes , Feminino , Humanos , Hibridização in Situ Fluorescente , Estudos ProspectivosRESUMO
We studied petroleum biodegradation by biostimulation by using water in oil in water (W/O/W) double emulsions. These emulsions were developed using seawater, canola oil, surfactants, and mineral salts as sources of NPK. The emulsions were used in the simulation of hydrocarbon bioremediation in oligotrophic sea water. Hydrocarbon biodegradation was evaluated by CO2 emissions from microcosms. We also evaluated the release of inorganic nutrients and the stability of the emulsion's droplets. The double emulsions improved CO2 emission from the microcosms, suggesting the increase in the hydrocarbon biodegradation. Mineral nutrients were gradually released from the emulsions supporting the hydrocarbon biodegradation. This was attributed to the formation of different diameters of droplets and therefore, varying stabilities of the droplets. Addition of the selected hydrocarbonoclastic isolates simulating bioaugmentation improved the hydrocarbon biodegradation. We conclude that the nutrient-rich W/O/W emulsion developed in this study is an effective biostimulation agent for bioremediation in oligotrophic aquatic environments.
Assuntos
Bactérias/metabolismo , Hidrocarbonetos/metabolismo , Petróleo/metabolismo , Água do Mar/microbiologia , Poluentes Químicos da Água/metabolismo , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Biodegradação Ambiental , Emulsões/análise , Emulsões/metabolismo , Petróleo/análise , Água do Mar/análise , Poluentes Químicos da Água/análiseRESUMO
BACKGROUND AND AIMS: Non-alcoholic steatohepatitis (NASH) has multifactorial etiopathogenesis, and intestinal microbiota is co-responsible in this process. The aim of this study was to evaluate the intestinal microbiota in NASH patients with different metabolic profiles. METHODS: Patients with biopsy-proven NASH were evaluated. Subjects were divided into two groups according to their metabolic profile, with or without metabolic syndrome (MS). Their characteristics in relation to liver disease and intestinal microbiota were analyzed. To evaluate the microbiota, breath tests to investigate small intestinal bacterial overgrowth (SIBO) and fecal microbiota analysis by fluorescence in situ hybridization (FISH) were performed. RESULTS: There was a high prevalence of SIBO in both groups, with no significant difference between them. Breathing tests were positive in 43.8% of patients with MS and 50% of those without MS. There was a significant difference regarding the quantification of Verrucomicrobiales, less abundant in patients with NASH without MS. Its lower concentration also correlated with higher serum ferritin levels and higher hepatocyte ballooning. This order of bacteria, through its representative in human microbiota, Akkermansia muciniphila, is associated with mucosal protection and metabolic processes with liver aggression. CONCLUSIONS: Our results suggested that lower Verrucomicrobiales concentration is associated with higher inflammatory activity in patients with NASH without MS, where the disease etiopathogenesis does not have its classic metabolic substrate.
Assuntos
Bactérias/crescimento & desenvolvimento , Microbioma Gastrointestinal , Intestinos/microbiologia , Síndrome Metabólica/microbiologia , Hepatopatia Gordurosa não Alcoólica/microbiologia , Adulto , Estudos Transversais , Disbiose , Fezes/microbiologia , Feminino , Humanos , Masculino , Síndrome Metabólica/diagnóstico , Pessoa de Meia-Idade , Hepatopatia Gordurosa não Alcoólica/diagnóstico , Projetos PilotoRESUMO
BACKGROUND AND AIMS: Modulation of the gut microbiota emerges as a therapeutic possibility to improve health. Our objective was to compare the impact of three months of intervention with diet plus nutritional orientation versus only nutritional orientation on the gut microbiota and metabolic-nutritional profile of outpatients with non-alcoholic steatohepatitis. METHODS: It was a randomized clinical trial with 40 outpatients (49.48 ± 10.3 years), allocated in two groups: DIET group (n=20), who received diet (1.651.34 ± 263.25 kcal; 47% carbohydrates, 28% lipids, 25% proteins, 30 g fibers) and nutritional orientation, and control group (n = 20), which received only nutritional orientation. RESULTS: The DIET group, in relation to baseline, presented a reduction in body weight (p<0.001), BMI (p<0.001), waist circumference (p=0.001), percentage of fat (p=0.002), serum aspartate aminotransferase (p<0.001), alanine aminotransferase (p<0.001), γ-glutamyltransferase (p=0.001), glycemia (p=0.003), homeostasis model assessment of insulin resistance (p=0.017), total cholesterol (p=0.014), and triacylglycerols (p=0.008), whereas the control group did not present changes. After intervention, the small intestinal bacterial overgrowth frequency was 30% in the DIET group and 45% in the control group (p=0.327). In the DIET group, an increase in the density of total microorganisms (3.76 ± 7.17 x 10 8 cells g -1 ; p=0.048) was detected, while in the control group reduced Bacteroidetes (-0.77 ± 2.01 x 10 8 cells g -1 , p=0.044) and Verrucomicrobiales (-0.46 ± 0.75 x 10 8 cells g -1 ; p=0.022) were observed. CONCLUSIONS: The results suggest that exclusively dietary modifications contribute to health promotion in non-alcoholic steatohepatitis and should be the basis of nutritional treatment for this condition.
Assuntos
Dieta Saudável , Metabolismo Energético , Microbioma Gastrointestinal , Hepatopatia Gordurosa não Alcoólica/dietoterapia , Estado Nutricional , Pacientes Ambulatoriais , Adulto , Brasil , Disbiose , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Hepatopatia Gordurosa não Alcoólica/sangue , Hepatopatia Gordurosa não Alcoólica/microbiologia , Hepatopatia Gordurosa não Alcoólica/fisiopatologia , Valor Nutritivo , Fatores de Tempo , Resultado do TratamentoRESUMO
Probiotics are widely used in the food industry and may affect the oral microbiota. This study aimed to evaluate the effect of petit-suisse plus probiotic on the microbiota of children's saliva. Strawberry flavor petit-suisse cheese plus green banana flour without Lactobacillus casei (control) and with addition of Lactobacillus casei (probiotic) were prepared and used in the experiments. The feasibility of adding probiotic to petit-suisse was assessed over 28â¯days. Saliva samples from volunteers who consumed the petit-suisses produced were collected before the period of consumption of the products (T0), on the last day of consumption of petit-suisse (T1) and two weeks after the consumption stopped (T2 - post treatment). The samples were immediately fixed with paraformaldehyde in a final concentration of 2%, after which the bacteria of interest were identified by Fluorescent In Situ Hybridization (FISH) and counted with the aid of an epifluorescence microscope. Lactic bacteria were viable between 108 and 109â¯CFU·g-1 for 28â¯days of storage at 4⯰C. Both products (control and with L. casei added) were able to significantly reduce (pâ¯<â¯0.05) the total number of microorganisms and Streptococcus mutans in the volunteers' saliva. However, only the product plus L. casei decreased density of Agreggatibacter actinomycetemcomitans, as well as being able to maintain the low density of Porphyromonas gingivalis post treatment. Therefore, the petit-suisse cheese developed showed the ability to carry probiotic microorganism, being a potential alternative for reducing potentially pathogenic microbiota in the oral cavity.
Assuntos
Queijo/microbiologia , Lacticaseibacillus casei/fisiologia , Probióticos , Saliva/microbiologia , Bactérias/genética , Criança , Humanos , Hibridização in Situ Fluorescente , Microbiota , Boca/microbiologia , Streptococcus mutansRESUMO
Although lifestyle and physiology in obese individuals are accepted to lead to changes in the intestinal microbiota, uncertainty remains about microbiota dysbiosis, and xenobiotics intake, as a source of selective pressure, independent of antimicrobial chemotherapy. The aim of this study was to compare the occurrence of antimicrobial resistance genetic markers (ARG) in faecal specimens of eutrophic, overweight and obese individuals, and their correlation with xenobiotic intake and gut bacteria density. Methods: This was a cross-sectional case-controlled study including 72 adult participants with no record of intestinal or systemic diseases, or recent use of antimicrobials, grouped as eutrophic, overweight, or obese. Anthropometric profile, eating habits and oral xenobiotics intake were recorded. Faecal metagenomic DNA was used to screen for ARG by PCR, and to measure bacterial groups by fluorescence in situ hybridization (FISH). Student's t and Wilcoxon tests were used to compare means and differences in ARG detection (95% confidence intervals). Correlation analyses (odds ratio) and relationships between bacteria density and ARG were determined. Results: Increase in abdominal circumference, waist circumference, hip, waist-hip ratio, BMI, carbohydrate, fibres, and total calorie intakes were different from eutrophic to obese participants. Habitual use of antihypertensive and anti-inflammatory drugs, antacids, and artificial sweeteners were associated mainly with obesity and overweight. Nutritional supplements were associated to the eutrophic group. ARG screening showed differences being more frequent among obese, and positive for 27 genetic markers related to ß-lactams, tetracyclines, the macrolide lincosamide and streptogramin group, quinolones, sulfonamides, aminoglycosides, and efflux pump. Positive correlation between ARG and BMI, caloric intake, and intake of xenobiotics, was observed for obese individuals. Relationships among ARG detection and bacteria densities were also different. Conclusions: This study reinforces the hypothesis that obese individuals may harbour an altered gut microbiota, if compared to eutrophic. The overweight individuals display a transitional gut microbiota which seems to be between eutrophic and obese. Furthermore, the increased xenobiotic intake associated to obesity may play an important role in the antimicrobial resistance phenomenon.
Assuntos
Resistência Microbiana a Medicamentos/genética , Trato Gastrointestinal/microbiologia , Sobrepeso/microbiologia , Adulto , Antiácidos/uso terapêutico , Anti-Inflamatórios não Esteroides/uso terapêutico , Anti-Hipertensivos/uso terapêutico , Suplementos Nutricionais , Fezes/microbiologia , Feminino , Microbioma Gastrointestinal/genética , Humanos , Hibridização in Situ Fluorescente , Masculino , Pessoa de Meia-Idade , Edulcorantes/administração & dosagem , Xenobióticos/administração & dosagem , Adulto JovemRESUMO
This study was aimed to provide a longitudinal overview of the subgingival bacterial microbiome using fluorescence in situ hybridization (FISH) technique, in women in the second trimester of pregnancy (between 14 and 24 weeks), and 48 h and 8 weeks postpartum. Of 31 women evaluated during pregnancy, 24 returned for the 48-h and 18 for their 8-week exams postpartum. Probing depth (PD), bleeding on probing, clinical attachment level, and presence of calculus were recorded. Subgingival plaque samples were collected, and FISH was used to identify the numbers of eight periodontal pathogens. Friedman test was used to compare differences between follow-up examinations, followed by a multiple comparison test for a post hoc pairwise comparison. Clinically, a significantly greater number of teeth with PD = 4-5 mm were found during pregnancy than on postpartum examinations. Microbial analysis showed a statistically significant decrease in cell count over the study period for Prevotella nigrescens. P. intermedia, Campylobacter rectus, and Porphyromonas gingivalis also decrease, although not significantly, and Aggregatibacter actinomycetemcomitans increased. No significant changes were found for Fusobacterium nucleatum, Treponema denticola, or Tannerella forsythia. Our data demonstrate a change in the subgingival microbiota during pregnancy, at least for P. nigrescens.
Assuntos
Gengiva/microbiologia , Bactérias Gram-Negativas/isolamento & purificação , Periodonto/microbiologia , Adulto , Carga Bacteriana , Biofilmes/crescimento & desenvolvimento , Placa Dentária/microbiologia , Feminino , Idade Gestacional , Humanos , Hibridização in Situ Fluorescente , Estudos Longitudinais , Microbiota , Índice Periodontal , Periodontite/microbiologia , Período Pós-Parto , Gravidez , Complicações Infecciosas na Gravidez/microbiologia , Valores de Referência , Estatísticas não Paramétricas , Tannerella forsythia/isolamento & purificação , Fatores de Tempo , Adulto JovemRESUMO
Rivers and streams are important reservoirs of freshwater for human consumption. These ecosystems are threatened by increasing urbanization, because raw sewage discharged into them alters their nutrient content and may affect the composition of their microbial community. In the present study, we investigate the taxonomic and functional profile of the microbial community in an urban lotic environment. Samples of running water were collected at two points in the São Pedro stream: an upstream preserved and non-urbanized area, and a polluted urbanized area with discharged sewage. The metagenomic DNA was sequenced by pyrosequencing. Differences were observed in the community composition at the two sites. The non-urbanized area was overrepresented by genera of ubiquitous microbes that act in the maintenance of environments. In contrast, the urbanized metagenome was rich in genera pathogenic to humans. The functional profile indicated that the microbes act on the metabolism of methane, nitrogen and sulfur, especially in the urbanized area. It was also found that virulence/defense (antibiotic resistance and metal resistance) and stress response-related genes were disseminated in the urbanized environment. The structure of the microbial community was altered by uncontrolled anthropic interference, highlighting the selective pressure imposed by high loads of urban sewage discharged into freshwater environments.
Assuntos
Metagenoma , Microbiota , Rios/microbiologia , Urbanização , Microbiologia da Água , Código de Barras de DNA Taxonômico , Ecossistema , Metabolismo Energético , Humanos , Redes e Vias Metabólicas , Metagenômica , Filogenia , RNA Ribossômico 16S/genéticaRESUMO
Abstract Information about bacterial diversity, such as the number of each species in the root canals of primary teeth, contributes to improving our effective management of infections of endodontic origin in primary teeth. This study made a qualitative and quantitative assessment of the bacteria in the root canals of primary teeth with necrotic pulp, using the fluorescence in situ hybridization (FISH) technique. Thirty-one primary teeth with pulp necrosis from 31 children were evaluated using the FISH technique, to detect the presence and density of Aggregatibacter actinomycetemcomitans, Campylobacter rectus, Enterococcus faecalis, Fusobacterium nucleatum, Porphyromonas gingivalis, Prevotella intermedia, Prevotella nigrescens, Streptococcus, Streptococcus mutans, Streptococcus sobrinus, Tannerella forsythia and Treponema denticola. Descriptive measures explained the data related to density, and Student's t-test assessed the differences among the densities of each bacterium, according to signs and symptoms. The bacterial density was paired and correlated. All bacteria tested were detected and identified in all the samples. The average number of bacterial individuals from each species ranged from 1.9 x 108 cells/mL (S. mutans) to 3.1 x 108 cells/mL (F. nucleatum) (p > 0.05). The sum of the mean counts of each bacterium represented almost 80% of the entire microbial community. Patients with pain had significantly more T. denticola, and those with edema showed a greater density of Streptococcus and P. nigrescens (p < 0.05). This study revealed that all 12 bacteria evaluated were found in all primary teeth with pulp necrosis. There was no predominance among the species studied; all species had a similar number of individuals.
Assuntos
Humanos , Criança , Dente Decíduo , Necrose da Polpa Dentária , Cavidade Pulpar , DNA Bacteriano , Hibridização in Situ Fluorescente , Porphyromonas gingivalis , Prevotella intermediaRESUMO
ABSTRACT: Litopenaeus vannamei is the most cultured marine shrimp in all types of systems including the Bioflocs Technology System (BFT). Bioflocs are formed by microorganisms, among these, autotrophic bacteria are responsible for the nitrification process. This study aimed to identify and promote the development of nitrifying bacteria by adding artificial substrates and biofloc inoculum in L. vannamei culture in a BFT system. The experiment consisted of four treatments with three replics (4x3) as follows: (1) Control: clear water in which bioflocs were formed; (2) IN (10%): clear water with biofloc inoculum (10%); (3) IB: clear water with substrate (immature "bioballs"); and (4) MB: clear water with mature "bioballs" inoculum from a recirculation system. Treatments were stocked with shrimp juveniles (4.92±0.45 g) in 12 tanks with 200 L working volume at a stocking density of 200 shrimp/m³. Shrimps were fed twice a day with a commercial feed (38% CP) following a feeding table, and daily observations intake were made over the four weeks of the experiment. Biofloc and "bioballs" samples were collected to detect the growth of the population of nitrifying and heterotrophic bacteria by FISH. There was no significant difference between treatments (P>0.05) for survival, obtaining mean values greater than 88%. The IN (10%) treatment had lower concentrations of ammonia and nitrite, and nitrate concentration increased, while MB had a higher weight and biomass final, productivity, weekly weight gain and lower conversion of apparent feed for production performance results.
RESUMO: Litopenaeus vannamei é o camarão marinho mais cultivado em todos os tipos de sistemas, incluindo o Sistema de Tecnologia de Bioflocos (BFT). Os bioflocos são formados por microorganismos, entre estes, bactérias autotróficas que são responsáveis pelo processo de nitrificação. Este estudo teve como objetivo identificar e promover o desenvolvimento de bactérias nitrificantes pela adição de substratos artificiais e inóculo de bioflocos no cultivo de L. vannamei em sistema BFT. O experimento consistiu de quatro tratamentos com três repetições (4x3), sendo: (1) Controle: água limpa, na qual foram formados os bioflocos; (2) IN (10%): água limpa com inóculo de bioflocos (10%); (3) BI: água limpa com substrato ("bioballs" imaturos); e (4) BM: água limpa com inóculo de "bioballs" maduros de um sistema de recirculação. Para tanto, os tratamentos foram estocados com juvenis de camarão (4,92±0,45 g) em 12 tanques com 200 L de volume útil com densidade de 200 camarões/m³. Os camarões foram alimentados duas vezes ao dia com ração comercial (38% PB) seguindo uma tabela de alimentação, e observações diárias foram feitas ao longo das quatro semanas de experimento. Amostras de bioflocos e "bioballs" foram coletadas para detectar o crescimento da população de bactérias nitrificantes e heterotróficas por FISH. Não houve diferença significativa entre os tratamentos (P>0,05) para sobrevivência, obtendo-se valores médios superiores a 88%. O tratamento com IN (10%) apresentou menores concentrações de amônia e nitrito, e a concentração de nitrato aumentou, enquanto o BM apresentou maior peso e biomassa final, produtividade, ganho de peso semanal e menor conversão alimentar aparente para resultados de desempenho zootécnico.
RESUMO
Techniques to decrease losses from bacterial diseases are always important to improve the fish production. The use of antagonistic substances (bacteriocins) has been proven to be a viable option. The aim of this study was to evaluate different methods of purification for bacteriocin like inhibitory substances (BLIS). For the purification process, we isolated and used two Gram-positive bacilli that produce antagonistic substances for pathogens in aquaculture. Tests for detection of interfering factors were also performed. After the confirmation that the antagonistic action was due the BLIS activity, we carried out the purification methods. The methods tested were: cell free supernatant, acid extraction and ammonium sulfate precipitation at two concentrations (20 and 50%). Salmonella Tiphy CFP/IAL1472 and Aeromonas hydrophila (isolated in a tilapia production environment) were used as indicators of the efficiency of extracts in controlling pathogenic potentials. Ammonium sulfate precipitation at 50% was the most appropriate for purifying the antagonistic substance for both indicators. The extracts of the two isolates remained active for 22 days at 25ºC. These are promising results regarding the water and fish health without the use of antibiotics, in this manner being a safer environmental practice.
Técnicas para diminuir as perdas causadas por doenças bacterianas são importantes para melhorar continuamente a produção de pescado. O uso de substâncias antagônicas (bacteriocinas) tem-se mostrado uma opção viável. O objetivo do trabalho foi avaliar diferentes métodos de purificação de bacteriocinas como substâncias inibidoras (BLIS). Dois bacilos Gram-positivos, produtores de substâncias antagonistas para agentes patogênicos da aquicultura, foram utilizados em processos de purificação. Depois de confirmada a ação antagônica pela atividade de BLIS, os métodos de purificação foram realizados. Os métodos testados foram: células livres de sobrenadante, extração ácida e precipitação por sulfato de amônia em duas concentrações (20 e 50%). Salmonella Typhi PCP/IAL1472 e Aeromonas hydrophila (isolada de um ambiente de tilapicultura) foram utilizadas como indicadores de eficiência dos extratos. O precipitado por sulfato de amônio a 50% foi o mais adequado para purificar a substância antagonista para ambos os isolados indicadores. Os extratos dos dois isolados permaneceram ativos por 22 dias em 25ºC. Estes resultados são promissores do ponto de vista da manutenção da sanidade da água e dos peixes, sem uso de antibióticos, constituindo uma prática ambientalmente mais segura.
Assuntos
Bacilos Gram-Positivos/isolamento & purificação , Bacteriocinas/isolamento & purificação , Pesqueiros/análise , AquiculturaRESUMO
The aim of this study was to use the fluorescence in situ hybridization (FISH) technique to test the hypothesis of qualitative and quantitative differences of 8 periodontopathogens between pregnant and non-pregnant women. This cross-sectional study included 20 pregnant women in their second trimester of pregnancy and 20 non-pregnant women. Probing depth, bleeding on probing, clinical attachment level, and presence of calculus were recorded. Subgingival plaque samples were collected and the FISH technique identified the presence and numbers of Aggregatibacter actinomycetemcomitans, Tannerella forsythia, Campylobacter rectus, Porphyromonas gingivalis, Treponema denticola, Fusobacterium nucleatum, Prevotella intermedia and Prevotella nigrescens. The Mann-Whitney U-test was applied to compare the data between the two groups. The mean age, ethnicity, marital status, education, and economic level in both groups were similar. The clinical parameters showed no significant differences between pregnant and non-pregnant women. The numbers of subgingival periodontopathogens were not found to be significantly different between groups, despite the higher mean counts of P. intermedia in pregnant women. Colonization patterns of the different bacteria most commonly associated with periodontal disease were not different in the subgingival plaque of pregnant and non-pregnant women.
Assuntos
Bactérias/crescimento & desenvolvimento , Carga Bacteriana/métodos , Biofilmes/crescimento & desenvolvimento , Gengiva/microbiologia , Adulto , Estudos Transversais , Inquéritos de Saúde Bucal , Feminino , Humanos , Hibridização in Situ Fluorescente/métodos , Doenças Periodontais/microbiologia , Gravidez , Complicações Infecciosas na Gravidez/microbiologia , Estatísticas não Paramétricas , Adulto JovemRESUMO
The use of antimicrobials and toxic metals should be considered carefully in aquaculture and surrounding environments. We aimed to evaluate medically relevant bacteria in an aquaculture system and their susceptibility to antimicrobials and toxic metals. Selective cultures for enterobacteria (ENT), non-fermenting Gram-negative rods (NFR) and Gram-positive cocci (GPC) were obtained from water samples collected in two different year seasons. The isolated bacteria were biochemically identified and antimicrobial and toxic metal susceptibility patterns were determined. Overall, 407 representative strains were recovered. In general, bacteria isolated from fish ponds showed higher multiple antibiotic resistance indices when compared to those isolated from a water-fed canal. Resistance to penicillin and azithromycin was observed more frequently in the GPC group, whereas resistance to ampicillin and ampicillin/sulbactam or gentamicin was observed more frequently in the ENT and NFR groups, respectively. All the isolated bacteria were tolerant to nickel, zinc, chromium and copper at high levels (≥1,024 µg mL(-1)), whereas tolerance to cadmium and mercury varied among the isolated bacteria (2-1,024 µg mL(-1)). Multidrug-resistant bacteria were more frequent and diverse in fish ponds than in the water-fed canal. A positive correlation was observed between antimicrobial resistance and metal tolerance. The data point out the need for water treatment associated with the aquaculture system.
Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana Múltipla , Bactérias Gram-Negativas/efeitos dos fármacos , Cocos Gram-Positivos/efeitos dos fármacos , Metais/farmacologia , Lagoas/microbiologia , Ampicilina/farmacologia , Aquicultura , Azitromicina/farmacologia , Cádmio/farmacologia , Cromo/farmacologia , Cobre/farmacologia , Enterobacteriaceae/efeitos dos fármacos , Enterobacteriaceae/isolamento & purificação , Gentamicinas/farmacologia , Bactérias Gram-Negativas/isolamento & purificação , Cocos Gram-Positivos/isolamento & purificação , Mercúrio/farmacologia , Testes de Sensibilidade Microbiana , Níquel/farmacologia , Penicilinas/farmacologia , Sulbactam/farmacologia , Microbiologia da Água , Zinco/farmacologia , Resistência beta-LactâmicaRESUMO
Abstract This study was aimed to provide a longitudinal overview of the subgingival bacterial microbiome using fluorescence in situ hybridization (FISH) technique, in women in the second trimester of pregnancy (between 14 and 24 weeks), and 48 h and 8 weeks postpartum. Of 31 women evaluated during pregnancy, 24 returned for the 48-h and 18 for their 8-week exams postpartum. Probing depth (PD), bleeding on probing, clinical attachment level, and presence of calculus were recorded. Subgingival plaque samples were collected, and FISH was used to identify the numbers of eight periodontal pathogens. Friedman test was used to compare differences between follow-up examinations, followed by a multiple comparison test for a post hoc pairwise comparison. Clinically, a significantly greater number of teeth with PD = 4-5 mm were found during pregnancy than on postpartum examinations. Microbial analysis showed a statistically significant decrease in cell count over the study period for Prevotella nigrescens. P. intermedia, Campylobacter rectus, and Porphyromonas gingivalis also decrease, although not significantly, and Aggregatibacter actinomycetemcomitans increased. No significant changes were found for Fusobacterium nucleatum, Treponema denticola, or Tannerella forsythia. Our data demonstrate a change in the subgingival microbiota during pregnancy, at least for P. nigrescens.