Lesões granulomatosas encontradas em bovinos abatidos para consumo

Com o objetivo auxiliar profissionais médico-veterinários no reconhecimento das lesões de bovinos encontradas na linha de inspeção de carnes em matadouros frigoríficos, três condições granulomatosas de bovinos foram pesquisadas e suas semelhanças e diferenças avaliadas. Essas três condições granulomatosas foram actinobacilose (causada por Actinobacillus lignieresii), actinomicose (causada por Actinomyces bovis) e mastite estafilocócica (causada por Staphylococcus aureus). Em 505 lesões encontradas em bovinos abatidos para consumo humano, 40 eram uma dessas três lesões granulomatosas: 24 eram actinobacilose, 10 eram actinomicose e seis eram mastite estafilocócica. De um modo geral, os aspectos macro e microscópicos dessas três lesões eram bastante semelhantes, mas suas localizações ajudavam a presumir sua etiologia. A. lignieresii afetou tecidos moles, principalmente língua e linfonodos da cabeça; A. bovis afetou o tecido ósseo, principalmente o da mandíbula; e S. aureus teve a glândula mamária como o tecido alvo. Histologicamente, os granulomas resultantes da infecção por qualquer um desses três agentes continham uma estrutura amorfa, eosinofílica, com clavas irradiadas, localizada centralmente; essa estrutura era rodeada por neutrófilos íntegros e degenerados, que, por sua vez, eram cercados por um manto de macrófagos epitelioides e ocasionais células gigantes multinucleadas. Esses mantos de macrófagos eram irregularmente infiltrados por linfócitos e plasmócitos que tendiam a se acumular na periferia da lesão, que era cercada por uma cápsula de tecido conjuntivo. Dependendo da aplicação do método de coloração adequado, o agente etiológico podia ser visto em cada um dos três tipos de lesão granulomatosa. No caso da mastite estafilocócica, cocos intralesionais foram observados tanto nas colorações por HE como nas de Gram, nessa última como cocos gram-positivos. O agente da actinobacilose (bacilos gram-negativos) e da actinomicose (bacilos gram-positivos) pôde ser observado somente nas colorações de Gram. Os diagnósticos diferenciais para essas três condições são discutidos.

Relationship between Daily Habits, Oral Microbiota and Caries with Special Reference to Xylitol

Caries is a plaque-associated multifactorial chronic disease. Oral hygiene habits, sugar, and oral micobiota interactions are important for caries to occur. Xylitol has been shown to reduce caries mainly due to its effects on mutans streptococci (MS). The purpose of this study was to evaluate the relationship of daily oral health habits and bacterial level on the caries occurrence and to study the effect of xylitol on the composition of oral microflora. A total of 192, 10-12 years old, male school children had been screened for salivary MS. Healthy subjects with high MS counts participated in two parallel double-blinded, randomised, controlled trials. In the first 5-week trial, subjects were assigned into xylitol (n=35) and sorbitol gum (n=38) groups. At baseline, children were examined using International Caries Detection and Assessment System (ICDAS) criteria and interviewed for oral health habits. In the second 4-week trial, subjects were assigned into xylitol (n=25) and saccharine mouthrinse (n=25) groups. In the end of both interventions, saliva samples were collected. The samples were analysed for changes in MS counts and changes in the composition of the oral microbiota assessed by the Human Oral Microbe Identification Microarray (HOMIM). Relationships between daily habits, bacterial levels and caries were evaluated. Daily use of sweets and soft drinks were the habits significantly associated with caries severity measured by ICDAS Caries Index (CI), while toothbrushing was the only habit associated with the low caries severity. Abiotrophia defectiva and Actinomyces meyeri/ A. odontolyticus were significantly higher in caries-affected children while Shuttleworthia satelles was significantly higher in caries-free children. Xylitol showed significant reduction in salivary levels of MS in both trials. No significant effects on other members of the microbiota were found when evaluated by HOMIM. In conclusion, other members of oral microbiota than MS may be associated with caries occurrence or absence. The use of xylitol had significant effect on MS with no effects on the other members of the salivary microbiota.

Distribución del fragmento katN de Nocardia brasiliensis en especies de actinomicetos patógenos

Tesis (Maestría en Ciencias con Especialidad en Mocrobliología Médica) UANL.

Estudios in vivo e in vitro de la sensibilidad de actinomadura madurae frente a diversos antimicrobianos de reciente desarrollo

Tesis (Maestría en Ciencias con Especialidad en Microbiología Médica) UANL

La respuesta de anticuerpos anti-proteínas intracelulares de actinomicetos productores de micetoma en animales infectados o inmunizados

Tesis (Maestría en Ciencias con Especialidad en Inmunología) UANL

Determinación in vitro del efecto de la combinación de amikacina y trimetoprim-sulfametoxazol sobre Nocardia brasiliensis

Tesis (Maestría en Ciencias con Especialidad en Microbiología Médica) U.A.N.L.

Estudio de la inmunogenicidad de las proteasas de Nocardia brasiliensis y su efecto inductor de protección en el micetoma experimental en ratones Balb

Tesis (Doctorado en Ciencias con Especialidad en Inmunología) UANL

Transfer of members of the genus Falcivibrio to the genus Mobiluncus, and emended description of the genus Mobiluncus

It has long been thought that the genera Mobiluncus and Falcivibrio contain the same organisms. Using a polyphasic approach, it was found that Mobiluncus curtisii and Mobiluncus mulieris were the same as Falcivibrio vaginalis and Falcivibrio grandis, respectively. As the genus name Mobiluncus takes precedence, it is proposed that F. vaginalis and F. grandis be transferred to the genus Mobiluncus. In agreement with previous studies, results from phenotypic tests did not support the separation of M. curtisii strains into its two subspecies, M. curtisii subsp. curtisii and M. curtisii subsp. holmesii. Phenotypic complexity within M. curtisii dictates that the species should be treated as a complex until more in-depth analyses of the species have been performed. Phylogenetic analyses, based on 16S rRNA gene sequences, demonstrated that the genus Mobiluncus was associated with Varibaculum cambriense and the two subspecies of Actinomyces neuii, and that A. neuii is only distantly related to Actinomyces sensu stricto.

Actinobaculum urinale sp. nov., from human urine

A hitherto undescribed Actinomyces-like bacterium was isolated from human urine. Based on its biochemical characteristics, the unidentified bacterium did not correspond to any currently described Actinomyces species or related taxa. Comparative 16S rRNA gene sequencing showed that the unknown bacterium exhibits a specific phylogenetic association with the genus Actinobaculum, but a sequence divergence of > 5% from the two currently recognized members of this genus, Actinobaculum schaalii and Actinobaculum suis, demonstrates that it represents a distinct species. Based on both phenotypic and 16S rRNA gene sequence considerations, it is proposed that the unknown bacterium from urine should be classified as a novel species, Actinobaculum urinale sp. nov. The type strain of Actinobaculum urinale is CCUG 46093(T) (= CIP 107424(T)).

Use of denaturing gradient gel electrophoresis to detect Actinobacteria associated with the human faecal microbiota

With the exceptions of the bifidobacteria, propionibacteria and coriobacteria, the Actinobacteria associated with the human gastrointestinal tract have received little attention. This has been due to the seeming absence of these bacteria from most clone libraries. In addition, many of these bacteria have fastidious growth and atmospheric requirements. A recent cultivation-based study has shown that the Actinobacteria of the human gut may be more diverse than previously thought. The aim of this study was to develop a denaturing gradient gel electrophoresis (DGGE) approach for characterizing Actinobacteria present in faecal samples. Amount of DNA added to the Actinobacteria-specific PCR used to generate strong PCR products of equal intenstity from faecal samples of five infants, nine adults and eight elderly adults was anti-correlated with counts of bacteria obtained using fluorescence in situ hybridization probe HGC69A. A nested PCR using Actinobacteria-specific and universal PCR-DGGE primers was used to generate profiles for the Actinobacteria. Cloning of sequences from the DGGE bands confirmed the specificity of the Actinobacteria-specific primers. In addition to members of the genus Bifidobacterium, species belonging to the genera Propionibacterium, Microbacterium, Brevibacterium, Actinomyces and Corynebacterium were found to be part of the faecal microbiota of healthy humans.

Microbiological profile of untreated subjects with localized aggressive periodontitis

Aim The microbial profile of localized aggressive periodontitis (LAgP) has not yet been determined. Therefore, the aim of this study was to evaluate the subgingival microbial composition of LAgP. Material and Methods One hundred and twenty subjects with LAgP (n=15), generalized aggressive periodontitis (GAgP, n=25), chronic periodontitis (ChP, n=30) or periodontal health (PH, n=50) underwent clinical and microbiological assessment. Nine subgingival plaque samples were collected from each subject and analysed for their content of 38 bacterial species using checkerboard DNA-DNA hybridization. Results Red complex and some orange complex species are the most numerous and prevalent periodontal pathogens in LAgP. The proportions of Aggregatibacter actinomycetemcomitans were elevated in shallow and intermediate pockets of LAgP subjects in comparison with those with GAgP or ChP, but not in deep sites. This species also showed a negative correlation with age and with the proportions of red complex pathogens. The host-compatible Actinomyces species were reduced in LAgP. Conclusion A. actinomycetemcomitans seems to be associated with the onset of LAgP, and Porphyromonas gingivalis, Tannerella forsythia, Treponema denticola, Campylobacter gracilis, Eubacterium nodatum and Prevotella intermedia play an important role in disease progression. Successful treatment of LAgP would involve a reduction in these pathogens and an increase in the Actinomyces species.

Microbiota saprófita associada à doença periodontal em cães

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

Detecção de subfertilidade em vacas leiteiras por meio de medidas anatômicas da região pélvica e do aparelho genital

O objetivo deste estudo foi mensurar as regiões que compõem a garupa da vaca leiteira, com aparelho desenvolvido para esse fim, e avaliar o efeito dessas variáveis na contaminação intra-uterina e na eficiência reprodutiva (intervalos parto-primeiro cio e parto-primeira inseminação, número de serviços por concepção e período de serviço). Foram usadas 252 vacas Holandesas, paridas há mais de 30 dias e não inseminadas. Realizaram-se medidas anatômicas da região pélvica e do aparelho genital e cultivo bacteriológico de material uterino. A influência das variáveis independentes (mensurações) sobre a presença de contaminantes intra-uterinos foi analisada por meio de regressão logística, a da presença de contaminantes intra-uterinos sobre a eficiência reprodutiva, por análise de variância, e a das variáveis independentes (mensurações) sobre a eficiência reprodutiva por meio de regressão linear múltipla. A presença de contaminantes intra-uterinos não foi influenciada por nenhuma das variáveis. Staphylococcus sp. (29,6%) foi o microrganismo mais encontrado no material uterino, seguido por Actinomyces pyogenes (26,0%), Streptococcus sp. (22,2%) e coliformes (22,2%), porém essa contaminação não teve efeito negativo nos índices reprodutivos. Das medidas anatômicas avaliadas, as que influenciaram as características reprodutivas foram: abertura do ílio (maior abertura menor eficiência reprodutiva), localização do óstio cranial da cérvice (quanto mais abdominal, piores os índices reprodutivos) e presença de urovagina (influência negativa na taxa de concepção).

Microbiota associated with chronic osteomyelitis of the jaws

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

Antibacterial activity of four glass ionomer cements used in atraumatic restorative treatment

The in vitro antibacterial activity of four glass ionomer cements ( Fuji IX, Ketac Molar, Vidrion R and Vitromolar) indicated for Atraumatic Restorative Treatment ( ART) was studied against strains of bacteria involved in the development of oral diseases, Streptococcus mutans, Streptococcus sobrinus, Lactobacillus acidophilus and Actinomyces viscosus. The agar plate diffusion test was used for the cultures, which included chlorhexidine as a positive control. The results demonstrated that all the cements evaluated presented antibacterial activity. Based on the results of this study, it can be concluded that Fuji IX and Ketac Molar presented the most effective antibacterial activity considering the ART approach.