Analyses of the genotoxic and mutagenic potential of the products formed after the biotransformation of the azo dye Disperse Red 1

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Probiotics for broiler chickens in Brazil: systematic review and meta-analysis

This study evaluated the efficacy of probiotic utilization as growth promoters in broiler chicken feeding using systematic literature review and meta-analysis. Thirty-five studies were recovered by the systematic review, 27 of which met the following criteria to be included in the meta-analysis: (1) Brazilian studies published between 1995 and 2005; (2) probiotics administered in the diet without growth promoter; (3) results included performance data with the respective coefficient of variation. Meta-analysis have shown that the probiotics promoted better weight gain and feed conversion than the negative control (no antimicrobial) in the initial phase (1 to 20-28 days); nevertheless, results were similar in the total period (1 to 35-48 days). Weight gain and feed conversion were similar between probiotics and the positive control (with antimicrobial) both in the initial and in the total periods. Viability in the total period improved with the use of probiotics in comparison to the negative or positive controls. Sensitivity analysis showed that the results of meta-analysis were coherent. The funnel plots and the Egger regression method evidenced that the studies published in Brazil do not present biased results. It is possible to conclude that the probiotics are a technically viable alternative to antimicrobial growth promoters in broiler feeding. Nevertheless, further studies are necessary to identify eventual differences among the probiotics commercially available in Brazil.

Staphylococcus spp. in the oral cavity and periodontal pockets of chronic periodontitis patients

Staphylococcus spp. não são usualmente isolados a partir da cavidade bucal. Quando presentes, são considerados pertencentes à microbiota transitória. Indivíduos que apresentam doença periodontal representam possíveis reservatórios dessas bactérias oportunistas na cavidade bucal. O uso de antibióticos para o tratamento da doença periodontal ou outras infecções pode predispor o aumento do número de Staphylococcus spp. na boca, pois estes adquirem facilmente resistência aos antibióticos, podendo resultar em superinfecção. O objetivo deste estudo foi verificar a presença de Staphylococcus spp. na cavidade bucal e nas bolsas periodontais de pacientes com periodontite crônica; identificar as cepas isoladas; verificar a relação entre a presença de Staphylococcus spp. na cavidade bucal e presença de bolsa periodontal. Participaram deste estudo 88 pacientes, entre 25 e 60 anos de idade e apresentando periodontite crônica, com pelo menos dois sítios com profundidade de sondagem maior ou igual a 5mm. Após anamnese e exame clínico periodontal foram feitas coletas de material da bolsa periodontal com cones de papel e da cavidade bucal por meio de bochechos. do total de pacientes 37,50% apresentaram Staphylococcus spp. na bolsa periodontal e 61,36% na cavidade bucal, sendo que 27,27% apresentaram a bactéria nos 2 sítios. S. epidermidis foi a espécie mais prevalente para bolsa periodontal (15,9%) e cavidade bucal (27,27%). Não houve diferença estatística significante quanto à presença desses microrganismos entre as faixas etárias e aumento da profundidade de sondagem. A presença de bactérias oportunistas na cavidade bucal pode representar dificuldades para a manutenção do tratamento periodontal.

The small bowel flora in individuals with cecoileal reflux

RACIONAL: Fato de observação não rara, é o encontro de refluxo cecoileal durante realização de enema opaco. As causas e conseqüências deste achado têm sido pouco estudadas. OBJETIVOS: Sabendo que a junção ileocecal exerce função de barreira e proteção contra a invasão do delgado pela flora colônica, realizou-se o presente estudo com a finalidade de investigar se existe contaminação ileal em indivíduos com refluxo cecoileal ao enema opaco. MÉTODOS: Investigaram-se 36 indivíduos, 30 mulheres e 6 homens, idade média de 54 anos, 25 com e 11 com ausência refluxo cecoileal. Todos submetidos a pesquisa de contaminação bacteriana do delgado por intermédio de teste respiratório com lactulose-H2 e a determinação do tempo de trânsito orocecal por meio de biossusceptometria de corrente alternada. A caracterização da contaminação do delgado foi baseada no encurtamento do tempo de trânsito orocecal medido pelo teste da lactulose-H2. RESULTADOS: A comparação dos valores basais do H2, do tempo de trânsito orocecal-H2 e tempo de trânsito orocecal-biossusceptometria de corrente alternada não diferiram estatisticamente entre os grupos com e sem refluxo cecoileal. Quando comparados os tempo de trânsito orocecal-H2 e tempo de trânsito orocecal-biossusceptometria, foi observado aumento de tendência de redução do primeiro em relação ao último nos grupos com refluxo cecoileal e correlação significante entre os dois métodos apenas no grupo-controle, inexistindo nos com refluxo cecoileal. CONCLUSÃO: Encurtamento do tempo de trânsito orocecal-H2 e sua perda de correlação com o tempo de trânsito orocecal-biossusceptometria observado em indivíduos com refluxo cecoileal, sugerem comportamento diferenciado deste grupo em relação ao grupo-controle. Possível explicação para as diferenças registradas entre os grupos, seria a presença de flora anômala nos indivíduos com refluxo cecoileal.

Cara inchada of cattle, an infectious, apparently soil antibiotics-dependant periodontitis in Brazil

O objetivo desta revisão das pesquisas sobre a cara inchada dos bovinos (CI), realizadas no decorrer dos últimos 30 anos, é de elucidar melhor a sua etiologia. A CI geralmente tem sido considerada de origem nutricional, causada primariamente por deficiência ou desequilíbrio mineral. A doença caracteriza-se por uma periodontite rapidamente progressiva, que afeta os tecidos peridentários a nível dos premolares e molares no período de erupção dos dentes e que se inicia geralmente em bezerros jovens. A doença causou grandes perdas econômicas aos pecuaristas da Região Centro-Oeste do Brasil, nas décadas de 1960 e 1970, com a ocupação de novas terras para criação de gado. O freqüente abaulamento lateral dos ossos maxilares nos bezerros, que deu à doença o nome popular de cara inchada, foi demonstrado ser conseqüente à periostite crônica ossificante resultante da alveolite purulenta da CI. Das lesões peridentárias foi isolado, em grande número, Bacteroides melaninogenicus, sempre junto com Actinomyces (Corynebacterium) pyogenes. Bactérias classificadas como pertencentes ao grupo sacarolí-tico e não-sacarolítico dos pigmentados de negro Bacteroides melaninogenicus e Bacteroides spp também foram isoladas, em pequeno número, de bovinos jovens sadios de fazendas CI-negativas. Ensaios in vitro mostraram que os antibióticos estreptomicina e actinomicina, bem como os sobrenadantes de cultivos de actinomicetos do solo de fazendas CI-positivas, aplicadas nas bactérias ensaiadas em concentrações subinibidoras, aumentaram significativamente (até 10 vezes) a aderência de B.melaninogenicus a células epiteliais da gengiva bovina. Esses antibióticos são produzidos no solo em conseqüência de um aumento do número de actinomicetos, incluindo os do gênero Streptomyces, quando há modificação de sua microbiota em áreas previamente ocupadas por mata virgem ou vegetação natural de Cerrado, que foram cultivadas pela primeira vez na formação de pastagem para o gado. em face da epidemiologia da CI, há fortes evidências de que a ingestão desses antibióticos pelos bovinos, junto com a forrageira, seja importante fator desencadeante para o desenvolvimento da periodontite. Através do aumento da aderência de B. melaninogenicus ao epitélio da gengiva marginal, em face da ingestão dos antibióticos pelos animais, as bactérias conseguem colonizar, formar a placa bacteriana e tornar-se patogênicas. Há evidência de que o fator desencadeante (aparentemente, os antibióticos) esteja também presente no leite de vacas-mães de bezerros afetados pela CI. Foi demonstrado que as bactérias envolvidas na periodontite produzem enzimas e endotoxinas capazes de ação destrutiva sobre os tecidos peridentários. A epidemiologia da CI, com a diminuição de sua incidência e o seu desaparecimento no decorrer dos anos, pode ser explicada pelo fato de que o prévio equílibrio da microbiota no solo virgem foi alcançado novamente e a produção dos antibióticos se reduziu. Desta maneira, a CI deve ser considerada como uma periodontite infecciosa multifatorial, causada sobretudo por bactérias anaeróbias pertencentes ao grupo Bacteroides melaninogenicus e, ao que tudo indica, desencadeada pela ingestão contínua, com a forrageira, de concentrações subinibidoras de antibióticos de solos recentememente cultivados. Esta hipótese é reforçada pela observação recente de novos surtos de CI, em áreas anteriormente positivas para a doença, em conseqüência da reforma de pastagens e capineiras após muitos anos. A natureza infecciosa da CI-periodontite foi confirmada através de experimento, em que virginiamicina mostrou-se eficaz no tratamento oral de bovinos afetados pela doença. Os antibióticos espiramicina e virginiamicina, usados como aditivos em suplementos minerais no campo, mostraram-se eficientes na prevenção da CI.

THE EFFECT OF CARBOHYDRATE ADMINISTRATION ON EXPERIMENTAL-INFECTION WITH SALMONELLA SEROTYPES IN CHICKENS

Carbohydrates and cultures of faecal microflora were administered to newly hatched chicks to prevent infection with Salmonella typhimurium Salmonella enteritidis, Salmonella agona and Salmonella infantis. Birds were killed 72 hours after challenge and the number of viable Salmonella organisms in their caecal contents estimated. Carbohydrates did not promote efficient control of infection with the Salmonella serotypes tested whereas cultures of faecal microflora completely prevented infection with all serotypes.

Longitudinal clinical evaluation of adjunct minocycline in the treatment of chronic periodontitis

Background: the clinical benefits of minocycline in combination with thorough scaling and root planing (SRP) have been examined in multicenter studies. The aim of this longitudinal investigation was to evaluate the clinical response to scaling and root planing combined with the use of locally delivered minocycline microspheres for 720 days in individuals with advanced chronic periodontitis.Methods: A total of 26 individuals aged 26 to 69 years (mean: 46.8 +/- 12.1 years) were included in this double-blind randomized clinical trial. After randomization, 13 individuals were selected for the test group (TG) and treated with SRP plus subgingival minocycline at baseline and 90, 180, and 270 days, and 13 individuals were selected for the control group (CG) and received SRP plus vehicle at the same time-points. Two homologous sites with probing depth (PD) >= 6 mm were chosen in each subject. To evaluate the clinical response after treatment, PD, plaque index (PI), and gingival index (GI) were assessed at baseline and 90, 180, 270, 360, and 720 days.Results: No statistical differences were found between test and control groups in relation to PD at the different timepoints. The mean values of PD demonstrated a higher reduction in the test group at 270 and 360 days. No statistical differences were observed at 90, 180, and 720 days between TG and CG (P < 0.05; Wilcoxon test). There were no statistically significant differences between TG and CG concerning PI and GI (P < 0.05; analysis of variance and t test) at all evaluated timepoints.Conclusion: Our findings demonstrated that both therapies reduced mean PD from 90 to 360 days; however, SRP combined with the use of subgingival minocycline showed a higher reduction at 270 and 360 days following therapy.

Ácidos orgânicos e microbiota cecal anaeróbia no controle da infecção experimental de frangos por Salmonella typhimurium e Salmonella enteritidis

The aim of this investigation was to study the effect of organic acids and/or anaerobic cecal microflora (ACM) on systemic and digestive infection of broilers by Salmonella typhimurium and S. enteritidis. ACM was used without previous bacterial identification. The treatment with ACM increased the resistance to Salmonella spp infection. Infection was more evident in caeca, followed by rectum and crop and did not interfere on body weight of broilers. Treated and control groups showed the same degree of infection at the end of the experiment. The use of ACM isolated or combined with acetic acid, reduced the colonization of the chick's digestive system by S. typhimurium and S. enteritidis. Acetic acid added to ACM did not potentiate the reduction of digestive system colonization. Except for the crop, the isolated use of acetic, propionic or formic acids did not reduce S. typhimurium and S. enteritidis, in caeca and rectum. The use of organic acids and ACM had little effect on reduction of caecum pH. The treatment with ACM reduced the quantity of S. enteritidis in the faeces. The reduction of caecum pH did not reduce the quantity of S. enteritidis in faeces. S. enteritidis was much more invasive than S. typhimurium and use of organic acids and ACM had little effect on reduction of systemic infection.

INTRAGASTRIC INFECTION OF CONVENTIONAL AND GERM-FREE MICE WITH GIARDIA-LAMBLIA

The effects of experimental infection with Giardia lamblia were studied in 30-day old conventional and germfree CFW mice (7 animals in each group) of both sexes. Cysts were observed in the feces of both groups 6 to 7 days after intragastric infection of each animal with about 2.5 x 10(5) G. lamblia trophozoites. Fecal cyst level was statistically higher in germfree mice (about 10(5) cysts/g feces) when compared with the conventional group (about 10(4) cysts/g feces). The peak of infection in the conventional group apparently occurred on the 10th day after infection as indicated by an increase of fecal weight and by histopathological examination. Intense infiltration of the lamina propria and high reactional hyperplasia of the lymphoid component were observed in the conventional group. There was no infiltration or hyperplasia in germfree infected mice and fecal weight was relatively constant throughout the experiment. These results suggest that, as is the case for other intestinal pathogenic protozoa, the intestinal microflora is indispensable for the expression of the pathogenicity but not for the multiplication of G. lamblia.

The relationship of oral malodor in patients with or without periodontal disease

Background: Halitosis has been correlated with the concentration of volatile sulfur compounds (VSC) produced in the oral cavity by metabolic activity of bacteria colonizing the periodontal area and the dorsum of the tongue. The aim of this study was to determine whether there is some relationship between the presence of N-benzoyl-DL-arginine-2-napthylamide (BANA)positive species Treponema denticola, Porphyromonas gingivalis, and Bacteroides forsythus and clinical and oral malodor parameters.Methods: Twenty-one subjects (21 to 59 years old) with probing depths (PD) >3.0 mm and 20 subjects (21 to 63 years old) with PD less than or equal to3.0 mm (controls) participated. The quality of the mouth air was assessed organoleptically, and a portable sulfide monitor was used to measure the concentration of VSC. Clinical parameters, plaque index (PI) and gingival index (GI), were obtained from 6 teeth. Samples for BANA test were taken from the dorsal surface of the tongue, saliva, and the 6 reference teeth.Results: the scores of PI, GI, subgingival samples that tested positive for BANA hydrolyzing species, organoleptic ratings, and VSC values were significantly higher in the subjects with PD >3.0 mm (P <0.01, Mann-Whitney U test). There was a correlation between BANA hydrolysis by subgingival plaque bacteria and VSC values (r = 0.55, P <0.01), and between GI and VSC values (r = 0.48, P <0.05) in patients with PD >3.0 mm. There was no significant correlation between these parameters in the control group.Conclusion: These results confirm that the BANA hydrolyzing bacteria in the subgingival plaque are an important source of malodor production in the oral cavity.

Isolation of Malassezia pachydermatis and M. sympodialis from the external ear canal of cats with and without otitis externa

The objective of this study was to determine the presence of Malassezia spp. in the external ear canal of cats with and without otitis. Forty-five animals were studied, 20 with and 25 without otitis externa (OE). Cerumen or secretion from external ear canal samples was cultured on modified Mycosel agar and sterile olive oil was added to the surface of the medium before specimen seeding. The isolates were analysed for macro- and micromorphology and identified by catalase tests and on the basis of growth on Tween 20, 40, 60 and 80. Malassezia spp. were isolated from 15 out of 20 (75%) animals with otitis and from 7 out of 25 (28%) cats without OE; the difference between the two groups was statistically significant (P <= 0.05). Malassezia pachydermatis and M. sympodialis were isolated from 60% (12/20) and 40% (8/20) of cats with otitis, respectively, with no significant difference in the frequency of isolation between the two species. In the microflora of the healthy ear canal M pachydermatis was significantly more common (6/25, 24%) than M sympodialis (1/25, 4%). The present investigation confirms that M sympodialis can also act as an actiological agent of feline OE, and if commercial veterinary laboratories do not use media with added lipids for the isolation of Malassezia spp., this might lead to false-negative results.

Periodontal status in smokers and never-smokers: Clinical findings and real-time polymerase chain reaction quantification of putative periodontal pathogens

Background: Smoking is a well-known risk factor for destructive periodontal disease, but its relationship with periodontal status and subgingival microbiota remains unclear. Inherent limitations of microbiological methods previously used may partly explain these mixed results, and real-time polymerase chain reaction (PCR) has been presented as a valid alternative. The aim of the present study was to investigate the clinical condition and microbiological profile of patients with chronic periodontitis as related to the habit of smoking.Methods: Fifty patients (33 to 59 years old), 25 smokers and 25 never-smokers, constituted the sample. The visible plaque index (VPI), gingival bleeding index (GBI), bleeding on probing (BOP), periodontal probing depth (PD), clinical attachment loss (CAL), and gingival crevicular fluid (GCF) volume were recorded. Real-time PCR quantified Porphyromonas gingivalis, Micromonas micros, Dialister pneumosintes, Actinobacillus actinomycetemcomitans and total bacteria in subgingival samples.Results: Smokers and never-smokers showed similar values for VPI, GBI, and BOP. Smokers had deeper PD in buccal/lingual sites and higher CAL independently of the tooth surface. The GCF volume was smaller in smokers, independent of the PD. Similar amounts of total bacteria and P. gingivalis were observed for both groups. Significantly higher numbers of D. pneumosintes and M. micros were present in smokers and associated with moderate and deep pockets. When heavy smokers were considered, higher counts of total bacteria, M. micros, and D. pneumosintes were observed.Conclusions: Smoking seems to have a detrimental impact on the periodontal status and microbiological profile of patients with periodontitis. Compared to never-smokers, smokers had deeper pockets, greater periodontal destruction, and higher counts of some putative periodontal pathogens.

Detection of T lymphocytes in intestine of broiler chicks treated with Lactobacillus spp. and challenged with Salmonella enterica serovar enteritidis

The expression of immune response in the form of leukocytic infiltrate by CD3+, CD4+, and CD8+ cells in the epithelium and in the intestinal lamina propria of chicks was studied in the present work by means of immunohistochemical reaction. The chicks were treated with Lactobacillus spp. or cecal microflora (CM) and experimentally challenged or not with Salmonella enterica serovar Enteritidis. The 320 birds utilized were divided into 4 groups containing 80 chicks each and submitted to treatments with Lactobacillus reuteri, Lactobacillus salivarius, Lactobacillus acidophilus, and CM. Each group was subdivided into 4 subgroups of 20 birds each and classified into a subgroup that did not receive treatment (negative control), subgroup treated, subgroup treated and challenged with Salmonella Enteritidis, and subgroup only challenged with Salmonella Enteritidis (positive control). The results obtained show that the treatment with L. reuteri, L. salivarius, L. acidophilus, or CM and challenged or not with Salmonella Enteritidis determine immune response in the form of leukocytic infiltrate by CD3+ and CD8+ lymphocytes followed by CD4+ in the epithelium and in the lamina propria of the duodenum, jejunum, and cecum of chicks up to 12 d of age. The quantity of CD3+ lymphocytes was significantly higher (P < 0.05) in the intestine of chicks treated with L. acidophilus or CM and challenged or not with Salmonella Enteritidis; however, the higher quantity of CD8+ lymphocytes was in the intestine of chicks treated with CM and challenged with Salmonella Enteritidis. The duodenum was the segment in which the immune response by T cells (CD3+, CD4+, and CD8+) was stimulated with the greatest intensity, followed by, respectively, the jejunum and cecum. The quantity of CD3+ lymphocytes present in the duodenum, jejunum, and cecum increases with the age of chicks, independent of the stimulus determined by treatments or challenge.

Escherichia coli phylogenetic group determination and its application in the identification of the major animal source of fecal contamination

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Flora do delgado em megas chagásicos: estudo pelo teste do H2 respiratório.

The author use the H2 breath test to study the small bowel microflora of chagasic patients with megaesophagus and/or megacolon. Compare this group with a control one. Find a significant increase (P < 0.05) in the small bowel flora of chagasic group. It is concluded that H2 breath is a simple and useful test to detect alteration in intestinal flora.