Bacterial translocation and mortality on rat model of intestinal ischemia and obstruction

Abstract Purpose: To develop an experimental model of intestinal ischemia and obstruction followed by surgical resection of the damaged segment and reestablishment of intestinal transit, looking at bacterial translocation and survival. Methods: After anesthesia, Wistar rats was subject to laparotomy, intestinal ischemia and obstruction through an ileal ligature 1.5cm of ileum cecal valve; and the mesenteric vessels that irrigate upstream of the obstruction site to approximately 7 to 10 cm were ligated. Abdominal wall was closed. Three, six or twenty-four hours after, rats were subject to enterectomy followed by an end to end anastomosis. After 24h, mesenteric lymph nodes, liver, spleen and lung tissues were surgically removed. It was studied survival rate and bacterial translocation. GraphPadPrism statistical program was used. Results: Animals with intestinal ischemia and obstruction for 3 hours survived 24 hours after enterectomy; 6hx24h: survival was 70% at 24 hours; 24hx24h: survival was 70% and 40%, before and after enterectomy, respectively. Culture of tissues showed positivity on the 6hx24h and negativity on the 3hx24h. Conclusion: The model that best approached the clinic was the one of 6x24h of ischemia and intestinal obstruction, in which it was observed bacterial translocation and low mortality rate.

Bacterial diversity of symptomatic primary endodontic infection by clonal analysis

Abstract The aim of this study was to explore the bacterial diversity of 10 root canals with acute apical abscess using clonal analysis. Samples were collected from 10 patients and submitted to bacterial DNA isolation, 16S rRNA gene amplification, cloning, and sequencing. A bacterial genomic library was constructed and bacterial diversity was estimated. The mean number of taxa per canal was 15, ranging from 11 to 21. A total of 689 clones were analyzed and 76 phylotypes identified, of which 47 (61.84%) were different species and 29 (38.15%) were taxa reported as yet-uncultivable or as yet-uncharacterized species. Prevotella spp., Fusobacterium nucleatum, Filifactor alocis, and Peptostreptococcus stomatis were the most frequently detected species, followed by Dialister invisus, Phocaeicola abscessus, the uncharacterized Lachnospiraceae oral clone, Porphyromonas spp., and Parvimonas micra. Eight phyla were detected and the most frequently identified taxa belonged to the phylum Firmicutes (43.5%), followed by Bacteroidetes (22.5%) and Proteobacteria (13.2%). No species was detected in all studied samples and some species were identified in only one case. It was concluded that acute primary endodontic infection is characterized by wide bacterial diversity and a high intersubject variability was observed. Anaerobic Gram-negative bacteria belonging to the phylum Firmicutes, followed by Bacteroidetes, were the most frequently detected microorganisms.

Utilidad de la espectrometría de masas MALDI-TOF en la identificación de bacterias anaerobias / Utility of MALDI-TOF MS for the identification of anaerobic bacteria

El análisis de espectrometría de masas mediante la metodología hoy conocida como MALDI-TOF MS (Matrix-assited laser desorption/ionization time-of-flight mass spectrometry) se ha convertido en un recurso de referencia para la identificación de microorganismos en microbiología clínica. No obstante, los datos relativos a algunos grupos de microorganismos son todavía controvertidos. El objetivo del presente estudio fue determinar la utilidad del MALDI-TOF MS para la identificación de aislamientos clínicos de bacterias anaerobias. Se analizaron 106 aislamientos de bacterias anaerobias mediante MALDI-TOF MS y por pruebas bioquímicas convencionales. En aquellos casos en los que la identificación por metodología convencional no era aplicable o frente a una discordancia de resultados entre las metodologías citadas, se realizó la secuenciación del gen 16S del ARNr. El método convencional y el MALDI-TOF MS coincidieron a nivel de género y especie en un 95,3 % de los casos considerando la totalidad de los aislamientos estudiados. Al considerar solo el conjunto de los bacilos gram negativos, la coincidencia fue del 91,4 %; entre los bacilos gram positivos, fue del 100 %; los 8 aislados de cocos gram positivos estudiados coincidieron y también hubo coincidencia en el único coco gram negativo incluido. Los datos obtenidos en este estudio demuestran que el MALDI-TOF MS ofrece la posibilidad de llegar a una adecuada identificación de bacterias anaerobias

The analysis by MALDI-TOF MS (Matrix-assited laser desorption/ionization time-of-flight mass spectrometry) has become a reference method for the identification of microorganisms in Clinical Microbiology. However, data on some groups of microorganisms are still controversial. The aim of this study is to determine the utility of MALDI-TOF MS for the identification of clinical isolates of anaerobic bacteria. One-hundred and six anaerobic bacteria isolates were analyzed by MALDI-TOF MS and by conventional biochemical tests. In those cases where identification by conventional methodology was not applicable or in the face of discordance between sequencing methodologies, 16 S rRNA gene sequence analysis was performed. The conventional method and MALDI-TOF MS agreed at genus and species level by 95.3 %. Concordance in gram-negative bacilli was 91.4% and 100% among gram-positive bacilli; there was also concordance both in the 8 isolates studied in gram-positive cocci and in the single gram-negative cocci included. The data obtained in this study demonstrate that MALDI-TOF MS offers the possibility of adequate identification of anaerobic bacteria

Peptidolytic microbial community of methanogenic reactors from two modified UASBs of brewery industries

We studied the peptide-degrading anaerobic communities of methanogenic reactors from two mesophilic full-scale modified upflow anaerobic sludge blanket (UASB) reactors treating brewery wastewater in Colombia. Most probable number (MPN) counts varied between 7.1 x 10(8) and 6.6 x 10(9) bacteria/g volatile suspended solids VSS (Methanogenic Reactor 1) and 7.2 x 10(6) and 6.4 x 10(7) bacteria/g (VSS) (Methanogenic Reactor 2). Metabolites detected in the highest positive MPN dilutions in both reactors were mostly acetate, propionate, isovalerate and, in some cases, negligible concentrations of butyrate. Using the highest positive dilutions of MPN counts, 50 dominant strains were isolated from both reactors, and 12 strains were selected for sequencing their 16S rRNA gene based on their phenotypic characteristics. The small-subunit rRNA gene sequences indicated that these strains were affiliated to the families Propionibacteriaceae, Clostridiaceae and Syntrophomonadaceae in the low G + C gram-positive group and Desulfovibrio spp. in the class d-Proteobacteria. The main metabolites detected in the highest positive dilutions of MPN and the presence of Syntrophomonadaceae indicate the effect of the syntrophic associations on the bioconversion of these substrates in methanogenic reactors. Additionally, the potential utilization of external electron acceptors for the complete degradation of amino acids by Clostridium strains confirms the relevance of these acceptors in the transformation of peptides and amino acids in these systems.

Biodiversity and phylogenetic analysis of culturable bacteria indigenous to Khewra salt mine of Pakistan and their industrial importance

Culturable bacterial biodiversity and industrial importance of the isolates indigenous to Khewra salt mine, Pakistan was assessed. PCR Amplification of 16S rDNA of isolates was carried out by using universal primers FD1 and rP1and products were sequenced commercially. These gene sequences were compared with other gene sequences in the GenBank databases to find the closely related sequences. The alignment of these sequences with sequences available from GenBank database was carried out to construct a phylogenetic tree for these bacteria. These genes were deposited to GenBank and accession numbers were obtained. Most of the isolates belonged to different species of genus Bacillus, sharing 92-99 percent 16S rDNA identity with the respective type strain. Other isolates had close similarities with Escherichia coli, Staphylococcus arlettae and Staphylococcus gallinarum with 97 percent, 98 percent and 99 percent 16S rDNA similarity respectively. The abilities of isolates to produce industrial enzymes (amylase, carboxymethylcellulase, xylanase, cellulase and protease) were checked. All isolates were tested against starch, carboxymethylcellulose (CMC), xylane, cellulose, and casein degradation in plate assays. BPT-5, 11,18,19 and 25 indicated the production of copious amounts of carbohydrates and protein degrading enzymes. Based on this study it can be concluded that Khewra salt mine is populated with diverse bacterial groups, which are potential source of industrial enzymes for commercial applications.

Avaliou-se a biodiversidade e a importância industrial de bactérias indígenas da mina de sal Khewra, Paquistão. Efetuou-se a amplificação do 16S rDNA dos isolados por PCR empregando-se os iniciadores universais FD1 e rP1, e os produtos foram seqüenciados comercialmente. Essas seqüências de genes foram comparadas com outras seqüências disponíveis no GenBank a fim de encontrar seqüências relacionadas, construindo-se uma árvore filogenética para essas bactérias. Os genes foram depositados no GenBank obtendo-se os números de acesso. A maioria dos isolados pertenceu a diferentes espécies do gênero Bacillus, apresentando 92-99 por cento de identidade de 16S rDNA com a respectiva cepa de referencia. Outros isolados apresentaram alta similaridade com Escherichia coli, Staphylococcus arlettae e Staphylococcus gallinarum, com 97 por cento, 98 por cento e 99 por cento de similaridade de16S rDNA, respectivamente. A capacidade dos isolados produzirem enzimas industriais (amilase, carboximetilcelulase, xilanase, celulase e protease) foi verificada. Todos os isolados foram testados em placas quanto a degradação de amido, carboximetilcelulose, xilana, celulose e caseína. Os isolados BPT-5, 11, 18, 19 e 25 produziram grandes quantidades de enzimas degradadoras de carboidratos e proteínas. Conclui-se que a mina de Sal Khewra apresenta diferentes grupos de bactérias, que são fontes potenciais de enzimas industriais de aplicação comercial.

Infected Pneumatocele Following Anaerobic Pneumonia in Adult

We report a case of an infected pneumatocele in the course of anaerobic pneumonia in an adult. To the best of our knowledge, anaerobic pneumonia complicated by a pneumatocele in an adult has not previously been described. The pneumatocele occurred on the fifth day of hospitalization, and rapidly increased in size, with the development of a subsequent mixed anaerobe infection. A pig-tail catheter was inserted and the pus drained. The bacterial culture from the pus was positive for three anaerobes: Bacteroid species, Peptostreptococcus asaccharolyticus and Fusobacterium species. Intravenous antibiotics and percutaneous catheter drainage resulted in a successful treatment.

Actividad “in vitro” de 10 antimicrobianos frente a bacterias anaerobias: Estudio multicéntrico, 1999-2002 / “In vitro” activity of ten antimicrobial agents against anaerobic bacteria. A collaborative study, 1999-2002

Se evaluó la actividad de ampicilina, ampicilina-sulbactama, cefoxitina, ceftriaxona, imipenem, piperacilina, piperacilina-tazobactama, clindamicina, metronidazol y azitromicina frente a 166 cepas de bacterias anaerobias aisladas en 8 hospitales de Buenos Aires. Se estudiaron: Bacteroides grupo fragilis (65), Fusobacterium spp. (26), Prevotella spp. (21), Porphyromonas spp. (10), Clostridium difficile (10), otros clostridios (12) y cocos gram-positivos (22). Las CIMs se determinaron usando el método patrón de dilución en agar recomendado por el NCCLS, documento M11-A5. Los antibióticos más activos fueron metronidazol y piperacilina-tazobactama que exhibieron valores de CIM90£ 2 µg/ml y £ 4 µg/ml frente a los microorganismos gram-negativos y £ 2 µg/ml y £ 8 µg/ml frente a los microorganismos gram-positivos, respectivamente. Entre los b-lactámicos el orden de actividad frente a bacilos gram-negativos fue: imipenem > piperacilina > cefoxitina > ceftriaxona > ampicilina. En gram-positivos la actividad decreciente fue: piperacilina> imipenem > cefoxitina > ceftriaxona > ampicilina. La mayoría de las especies estudiadas mostraron distintos niveles de resistencia con clindamicina y azitromicina. Sin embargo, el 90% de las cepas de Fusobacterium nucleatum y Por-phyromonas spp. fue inhibido por una concentración de 0,125 µg/ml de clindamicina y azitromicina, respectivamente.

The antimicrobial activity of ampicillin, ampicillin-sulbactam, cefoxitin, ceftriaxone, imipenem, piperacillin, piperacillin-tazobactam, clindamycin, metronidazole, and azitromycin was assesed against 166 strains of anaerobic bacteria recovered from eight hospitals in Buenos Aires. The strains studied were Bacteroidesfragilis group (65), Fusobacterium spp. (26), Prevotella spp. (21), Porphyromonas spp. (10), Clostridium difficile (10), other clostridia (12), and gram-positive cocci (22). The MICs were determined by the agar dilution method according to NCCLS document M11-A5. Metronidazole and piperacillin-tazobactam were the most active antimicrobial agents tested and exhibited MIC90values of £ 2 µg/ml and £ 4 µg/ml against gram-negative organisms, and £ 2 µg/ml, and £ 8 µg/ml against gram-positive organisms, respectively. Among b-lactams the activity against gram-negative rods was in the following order: imipenem> piperacillin > cefoxitin > ceftriaxone > ampicillin. Among the gram-positive bacteria the decreased activity was: piperacillin> imipenem> cefoxitin > ceftriaxone > ampicillin. The majority of the species studied showed different degrees of resistance to clindamycin and azitromycin. Nevertheless, 90% of Fusobacterium nucleatum and Porphyromonas spp. isolates were inhibited by 0.125 mg/ml of clindamycin and azitromycin, respectively.

Avaliaçäo clínica e microbiológica da saúde periodontal de crianças portadoras de fissura completa de lábio e palato unilateral comparada a de crianças sem fissuras na mesma faixa etária (5-6 anos) / Clinical and microbiological evaluation of periodontal condition in 5-6 years old children with unilateral complete cleft lip and palate compared to normal controls

Crianças portadoras de fissura de lábio e palato apresentam alteraçöes anatômicas decorrentes da própria anomalia e dos procedimentos terapêuticos para a sua reabilitaçäo, que podem predispô-las a um maior acúmulo de placa bacteriana, principalmente na regiäo anterior da maxila. Com o objetivo de comparar as condiçöes clínicas, através da utilizaçäo dos índices de placa (IP) e gengival (IG) de Loe (1967) e a presença das bactérias P. gingivalis, P. nigrescens e T. denticola, através da técnica "Slot Immunoblot", foram avaliadas 57 crianças com dentiçäo decídua e idades entre 5 e 6 anos, sendo 30 portadoras de fissura completa de lábio e palato unilateral (grupo experimental) e 27 crianças sem fissura (grupo controle). O IP médio do grupo experimental (1,82 ñ 0,38) foi superior ao do grupo controle (1,63 ñ 0,38), embora sem diferença estatisticamente significante, enquanto o IG médio do grupo experimental (1,05 ñ 0,22) foi significantemente superior ao do grupo controle (0,79 ñ 0,33) (p<0,05). No grupo experimental a área da fissura (2 sítios), com IP médio de 2,04 ñ 0,58 e IG médio de 1,11 ñ 0,26, quando comparada à regiäo posterior (4 sítios), com IP médio de 1,74 ñ 0,37 e IG médio de 1,04 ñ 0,26, mostrou difrença estatisticamente significante somente em relaçäo ao IP. Considerando a severidade, a maioria das crianças dos dois grupos apresentou IP de grau moderado, 73,33 por cento para o grupo experimental e 81,48 por cento para o grupo controle; enquanto, para o IG, a maioria apresentou severidade de grau baixo, sendo de 53,33 por cento para o grupo experimental e de 70,37 por cento para a grupo controle...

Microbiología de la enfermedad periodontal / Microbiology of periodontal disease

Existen una gran variedad de microorganismos relacionados con la enfermedad periodontal. Por lo general, los que se aíslan en la placa supragingival, son los mismos que se encuentran en la placa subgingival. Lo que hasta el momento se encuentra comprobado, es que las diferencias entre la placa asociada a sitios sanos en comparación con sitios periodontalmente afectados y aquella en posición supragingival comparada con la que se encuentra entre la encía y el diente, solamente difieren en la proporción relativa de algunos microorganismos en los conteos microbianos, parece que la mayor proporción de espiroquetas y bacteroides presentes en la placa subgingival, es el factor determinante para que la enfermedad esté activa

Determinación de bacterias patógenas en el área quirúrgica de gineco-obstetricia del Centro Materno-Infantil San Lorenzo de los Mina, mayo-junio 1989 / Determination of pathogen bacterias in surgical area of gyneco-obstetrics of the Centro Materno-Infantil San Lorenzo de los Mina, May-June 1989

Se realizó un estudio observacional, analítico y transversal, durante los meses de mayo y junio 1989, para la determinación de la presencia de bacterias patógenas en el área quirúrgica de gineco-obstetricia en el Centro Materno Infantil San Lorenzo, de Los Mina, Distrito Nacional, R. D. Se cultivaron muestras que fueron tomadas del personal médico, paramedico y del área quirúrgica (equipos hospitalarios, instrumental quirúrgico y ambiente del quirófano), de donde se tomaron 25 cultivos, 10 en el personal mencionado y 15 en el área quirúrgica. En total hubo crecimiento en 8 cultivos para un 32 por ciento , todos ellos bacilos gram negativos

Métodos para identificar bacilos gramnegativos no fermentadores (BGNnF) / Methods for the identification on non-fermentating gramnegative bacilli

Se emplearon los esquemas de King-Weaver, Gilardi, Pickett y el sistema automatizado Quantum II para identificar 53 cepas de los bacilos gramnegativos no fermentadores (BGNnF). Se encontró que los esquemas que identifican la totalidad de las cepas estudiadas son el de Gilardi y Pickett, seguido del esquema King-Weaver, con el cual se identificó a 46 cepas (86.8%). Empleando el sistema Quantum II, se identificaron 16 cepas (30.2%), siendo los géneros identificados: Pseudomonas 60.4%, Acinetobacter 28.3% y Moraxella en 11.3%. Después de analizar los resultados obtenidos, para la identificación de bacilos gramnegativos no fermentadores más frecuentemente aislados en nuestro medio, se propone el uso de las siguientes pruebas: reacción de citocromoxidasa, movilidad, desarrollo en gelosa Mac-Conkey y gelosa SS, base O/F con glucosa y manitol, reducción de nitratos y gas a partir de nitrato. Con estas pruebas se logra identificar con rapidez y bajo costo la mayoría de las cepas de BGNnF causantes de infecciones en el humano

Detección de bacilos gram negativos curvos anaerobios en pacientes con vaginosis / Anaerobic Gram negative curved rods detection in patients with vaginitis

Los bacilos curvos Gram negativos anaeróbicos, frecuentemente son detectados en la flora vaginal de mujeres con cuadros de vaginosis bacteriana. Existen dificultades para su aislamiento por su naturaleza anaeróbica y la competencia de la abundante flora acompañante. El presente trabajo trató de determinar por exámenes directos y cultivos la presencia de estos microorganismos en 100 mujeres con cuadros compatibles clínicamente con vaginosis y en 30 mujeres sin sintomatología clínica. Asimismo tratamos de definir la utilidad comparativa de las técnicas de diagnóstico disponibles y determinar el grupo etario más proclive a esta patología. Obtuvimos un 41% de detección para las técnicas directas y un 37% para los cultivos. Con la combinación de ambas alcanzamos el 46% de positividad, siendo el grupo testígo negativo para ambos métodos. Teniendo en cuenta la edad promedio del grupo de estudio vemos que esta patología se detecta en la etapa fértil de las mujeres estudiadas

Advantage of Sandiford's counterstain in detection of Gram negative bacteria in clinical specimens.

Confirmation of bacterial in clinical specimens using Gram's stain with the Sandiford's modification was found to be more useful, especially when Gram-negative bacteria with other forms coexisted, than ordinary Gram's stain. It was useful for staining histopathological specimens also. We believe that this method deserves wider recognition and should be used as a standard procedure in laboratories.