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Microbial resistance to antibiotics affects the control of clinical infections and is a growing concern in global public health. One important mechanism whereby micro-organisms acquire resistance is biofilm formation. This context has led to the investigation of new antimicrobial substances from plants popularly used in folk medicine. In this work, we studied the antimicrobial and antibiofilm activity of Zinnia peruviana roots, ziniolide (major root metabolite) and aerial parts against Staphylococcus aureus, Staphylococcus epidermidis, Listeria monocytogenes, Escherichia coli, Pseudomonas aeruginosa and Candida albicans. The minimum inhibitory and minimum microbicidal concentration and inhibition of biofilm production was determined. All Z. peruviana extracts showed antimicrobial activity, but that corresponding to the roots was the most active one. The best inhibitory and microbicidal activity was detected against Gram-positive bacteria (0·039-0·078 mg ml-1 ). The acetonic extract from Z. peruviana leaves showed moderate activity against Gram-positive bacteria (0·625 mg ml-1 ). Acetonic extract of Z. peruviana flowers showed weak activity (1·25-5 mg ml-1 ). All the extracts tested showed inhibition of biofilm formation, as well as the ziniolide, however, roots and flowers extracts showed higher antibiofilm activity particularly against Staphylococcus, Listeria and Candida. The extracts tested may be a promising natural alternative for the control of microbial infections.

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Acacia aroma, native plant from San Luis, Argentina, is commonly used as antiseptic and for healing of wounds. The present study was conducted to investigate the in vitro cytotoxicity and genotoxicity of hot aqueous extract (HAE) and ethanolic extract (EE) of A. aroma. The cytotoxic activity was assayed by neutral red uptake assay on Vero cell. Cell treatment with a range from 100 to 5000 µg/mL of HAE and EE showed that 500 µg/mL and 100 µg/mL were the maximum noncytotoxic concentrations, respectively. The CC50 was 658 µg/mL for EE and 1020 µg/mL for HAE. The genotoxicity was tested by the single-cell gel electrophoresis comet assay. The results obtained in the evaluation of DNA cellular damage exposed to varied concentrations of the HAE showed no significant genotoxic effect at range of 1-20 mg/mL. The EE at 20 mg/mL showed moderate genotoxic effect related to the increase of the DNA percentage contained in tail of the comet; DNA was classified in category 2. At concentrations below 5 mg/mL, the results of cytotoxicity and genotoxicity of aqueous and ethanolic extracts of Acacia aroma guarantee the safety at cell and genomic level. However further studies are needed for longer periods including animal models to confirm the findings.

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Antibacterial activity of organic and aqueous extracts of Acacia aroma was evaluated against methicillin-resistant Staphylococcus aureus (MRSA), methicillin sensitive Staphylococcus aureus (MSSA) and methicillin-resistant Staphylococcus epidermidis. Inhibition of bacterial growth was determined using agar diffusion and bioautographic methods. Among all assayed organic extracts only ethanolic and ethyl acetate extracts presented highest activities against all tested Staphylococcus strains with minimal inhibitory concentration (MIC) values ranging from 2.5 to 10 mg/ml and from 2.5 to 5 mg/ml respectively. The aqueous extracts show little antibacterial activity against Staphylococcus strains. The bioautography assay demonstrated well-defined growth inhibition zones against S. aureus in correspondence with flavonoids and saponins. A. aroma would be an interesting topic for further study and possibly for an alternative treatment for skin infections.

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Antibacterial activity of organic and aqueous extracts of Acacia aroma was evaluated against methicillin-resistant Staphylococcus aureus (MRSA), methicillin sensitive Staphylococcus aureus (MSSA) and methicillin-resistant Staphylococcus epidermidis. Inhibition of bacterial growth was determined using agar diffusion and bioautographic methods. Among all assayed organic extracts only ethanolic and ethyl acetate extracts presented highest activities against all tested Staphylococcus strains with minimal inhibitory concentration (MIC) values ranging from 2.5 to 10 mg/ml and from 2.5 to 5 mg/ml respectively. The aqueous extracts show little antibacterial activity against Staphylococcus strains. The bioautography assay demonstrated well-defined growth inhibition zones against S. aureus in correspondence with flavonoids and saponins. A. aroma would be an interesting topic for further study and possibly for an alternative treatment for skin infections.

RESUMEN

Antibacterial activity of organic and aqueous extracts of Acacia aroma was evaluated against methicillin-resistant Staphylococcus aureus (MRSA), methicillin sensitive Staphylococcus aureus (MSSA) and methicillin-resistant Staphylococcus epidermidis. Inhibition of bacterial growth was determined using agar diffusion and bioautographic methods. Among all assayed organic extracts only ethanolic and ethyl acetate extracts presented highest activities against all tested Staphylococcus strains with minimal inhibitory concentration (MIC) values ranging from 2.5 to 10 mg/ml and from 2.5 to 5 mg/ml respectively. The aqueous extracts show little antibacterial activity against Staphylococcus strains. The bioautography assay demonstrated well-defined growth inhibition zones against S. aureus in correspondence with flavonoids and saponins. A. aroma would be an interesting topic for further study and possibly for an alternative treatment for skin infections.

RESUMEN

The vacA and cagA genotypes of Helicobacter pylori exhibited distinct geographic distribution and correlation with severity of disease. In the above genotypes (obtained from 150 H. pylori-positive patients--139 with gastritis, 10 with ulcer and 1 patient with gastric cancer) combinations vacA s1/m1 and s2/m2 were detected using PCR in 75 and 25% of isolates, respectively, in patients with chronic gastritis. The of s1/m1 and s2/m2 combinations were also detected from ulcers (60 and 40%, respectively). The cagA was detected in 30% of isolates. Concentrated culture supernatants of 7 (64%) out of 11 H. pylori strains induced vacuolization in Vero cells in titers ranging from 1:5 to 1:40. The vacA s1 genotype was significantly associated with, but not predictive of the presence of vacuolating cytotoxin activity and the cagA gene.

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In this study, a total of 24 Listeria spp. strains were analyzed. Twenty-two isolates were obtained in San Luis (Argentina) from human, animal, and food samples. Two types of strains, Listeria monocytogenes CLIP 22762 and Listeria innocua CLIP 74915, were included as reference strains. All isolates were biochemically identified and characterized by serotyping, phage typing, and amplification of the flaA gene by polymerase chain reaction (PCR). Repetitive intergenic consensus (ERIC) sequence-based PCR was used to generate DNA fingerprints. On the basis of ERIC-PCR fingerprints, Listeria spp. strains were divided into three major clusters matching origin of isolation. ERIC-PCR fingerprints of human and animal isolates were different from those of food isolates. In addition, groups I and II included ten L. monocytogenes strains, and only one Listeria seeligeri strain. Group III included nine L. innocua strains and four L. monocytogenes strains. Computer evaluation of ERIC-PCR fingerprints allowed discrimination between the tested serotypes 1/2b, 4b, 6a, and 6b within each major cluster. The index of discrimination calculated was 0.94. This study suggests that the ERIC-PCR technique provides an alternative method for the identification of Listeria species and the discrimination of strains within one species.

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In this study, a total of 24 Listeria spp. strains were analyzed. Twenty-two isolates were obtained in San Luis (Argentina) from human, animal, and food samples. Two types of strains, Listeria monocytogenes CLIP 22762 and Listeria innocua CLIP 74915, were included as reference strains. All isolates were biochemically identified and characterized by serotyping, phage typing, and amplification of the flaA gene by polymerase chain reaction (PCR). Repetitive intergenic consensus (ERIC) sequence-based PCR was used to generate DNA fingerprints. On the basis of ERIC-PCR fingerprints, Listeria spp. strains were divided into three major clusters matching origin of isolation. ERIC-PCR fingerprints of human and animal isolates were different from those of food isolates. In addition, groups I and II included ten L. monocytogenes strains, and only one Listeria seeligeri strain. Group III included nine L. innocua strains and four L. monocytogenes strains. Computer evaluation of ERIC-PCR fingerprints allowed discrimination between the tested serotypes 1/2b, 4b, 6a, and 6b within each major cluster. The index of discrimination calculated was 0.94. This study suggests that the ERIC-PCR technique provides an alternative method for the identification of Listeria species and the discrimination of strains within one species.

En este estudio se analizaron 24 cepas de Listeria spp. De ellas, 22 fueron obtenidas en San Luis (Argentina), a partir de muestras humanas, de animales y alimentos. Se incluyeron 2 cepas de referencia Listeria monocytogenes CLIP 22762 y Listeria innocua CLIP 74915. Todos los aislamientos fueron identificados bioquímicamente y caracterizados por serotipificación, fagotipificación y detección del gen flaA por reacción en cadena de la polimerasa (PCR). Se generaron perfiles de bandas de ADN mediante la amplificación de secuencias repetitivas de consenso intergénico de enterobacterias (ERIC-PCR). De acuerdo a los resultados obtenidos por ERIC-PCR, las cepas de Listeria spp. fueron divididas en 3 grupos según su origen. Los perfiles de los aislamientos humanos y animales fueron distintos de los correspondientes a alimentos. Por otra parte, dentro de los grupos I y II se incluyeron 10 cepas de L. monocytogenes y solamente una de Listeria seeligeri. Dentro del grupo III no sólo estuvieron incluidas las 9 cepas de L. innocua sino también 4 de L. monocytogenes. La evaluación de los perfiles de bandas obtenidos por ERIC-PCR permitió la discriminación entre los serotipos ensayados 1/2b, 4b, 6a y 6b dentro de cada grupo. El índice de discriminación calculado para ERIC-PCR fue de 0,94. Los resultados sugieren que la técnica de ERIC-PCR provee un método alternativo válido para la identificación de especies de Listeria y, asimismo, permite la diferenciación de cepas dentro de una misma especie.

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In this study we present a relationship between different gastroduodenal pathologies and Helicobacter pylori infection. We used four diagnosis invasive methods for H. pylori infection: urease test (UT), histopathology (H), Gram stain (G) and culture (C). The upper gastrointestinal endoscopy of 300 dyspeptic patients showed that 71.6% had erosive congestive gastropathies, 13.6% had duodenopathies, 5.6% had gastric ulcer, 6.3% had duodenal ulcer and 2.6% had probable gastric neoplasia. We also correlated the data of water intake source with the pathologies. The percentage of infected patients with H. pylori was determined using: a) two simultaneous reference tests (UT and H), 54.3%, b) each test UT = 55.0%, H = 59.0%, G = 51.3%, and C = 43.0%. Sex, age and the source of water ingested did not show statistically significant differences.

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RESUMEN

In this study we present a relationship between different gastroduodenal pathologies and Helicobacter pylori infection. We used four diagnosis invasive methods for H. pylori infection: urease test (UT), histopathology (H), Gram stain (G) and culture (C). The upper gastrointestinal endoscopy of 300 dyspeptic patients showed that 71.6 had erosive congestive gastropathies, 13.6 had duodenopathies, 5.6 had gastric ulcer, 6.3 had duodenal ulcer and 2.6 had probable gastric neoplasia. We also correlated the data of water intake source with the pathologies. The percentage of infected patients with H. pylori was determined using: a) two simultaneous reference tests (UT and H), 54.3, b) each test UT = 55.0, H = 59.0, G = 51.3, and C = 43.0. Sex, age and the source of water ingested did not show statistically significant differences.(AU)

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RESUMEN

In this study we present a relationship between different gastroduodenal pathologies and Helicobacter pylori infection. We used four diagnosis invasive methods for H. pylori infection: urease test (UT), histopathology (H), Gram stain (G) and culture (C). The upper gastrointestinal endoscopy of 300 dyspeptic patients showed that 71.6 had erosive congestive gastropathies, 13.6 had duodenopathies, 5.6 had gastric ulcer, 6.3 had duodenal ulcer and 2.6 had probable gastric neoplasia. We also correlated the data of water intake source with the pathologies. The percentage of infected patients with H. pylori was determined using: a) two simultaneous reference tests (UT and H), 54.3, b) each test UT = 55.0, H = 59.0, G = 51.3, and C = 43.0. Sex, age and the source of water ingested did not show statistically significant differences.

Asunto(s)

RESUMEN

In this study we present a relationship between different gastroduodenal pathologies and Helicobacter pylori infection. We used four diagnosis invasive methods for H. pylori infection: urease test (UT), histopathology (H), Gram stain (G) and culture (C). The upper gastrointestinal endoscopy of 300 dyspeptic patients showed that 71.6

had erosive congestive gastropathies, 13.6

had duodenopathies, 5.6

had gastric ulcer, 6.3

had duodenal ulcer and 2.6

had probable gastric neoplasia. We also correlated the data of water intake source with the pathologies. The percentage of infected patients with H. pylori was determined using: a) two simultaneous reference tests (UT and H), 54.3

, b) each test UT = 55.0

, H = 59.0

, G = 51.3

, and C = 43.0

. Sex, age and the source of water ingested did not show statistically significant differences.

RESUMEN

It has been suggested that oral dissemination might be the major transmission vehicle for Helicobacter pylori, and that dental plaque might act as its reservoir. The presence of H. pylori was investigated in 62 odontological male and female patients (average age: 35 years old). Samples were taken from supragingival plaque, placed in 0.3 ml of thioglycolate broth, cultured within 12 h in Mueller-Hinton agar with the addition of 5-7% of sheep blood and antibiotic supplement, and incubated at 37 degrees C in microaerophilia for 5-7 days. Typical colonies were identified by gram, urease, oxidase and catalase. H. pylori was detected in a 15 year-old patient suffering from gastric acidity (1.61% positivity index). The medium used facilitated recovery of the agent from a sample abundant in germs. H. pylori was not recovered from the same patient 12 months later, suggesting that there might have been a transitory passage by gastric reflux or that the bacterium was acquired from an exogenous source.

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Se ha sugerido que la diseminación oral sería la principal vía de transmisión de Helicobacter pylori y la placa dental podría actuar como reservorio. Se investigó su presencia en 62 pacientes odontológicos de ambos sexos, edad promedio 35 años. Las muestras, tomadas de placas supragingival, colocadas en 0,3 ml de caldo tioglicolato, fueron cultivadas dentro de las 12 h en agar Mueller-Hinton con 5-7 por ciento de sangre de oveja y suplemento antibiótico e incubadas a 37ºC en microaerofilia 5-7 días. Las colonias típicas se identificaron por gram, ureasa, oxidasa y catalasa. H. pylori fue detectado en un paciente de 15 años que padecía acidez gástrica (índice de positividad 1,61 por ciento). El medio utilizado facilitó la

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RESUMEN

Se ha sugerido que la diseminación oral sería la principal vía de transmisión de Helicobacter pylori y la placa dental podría actuar como reservorio. Se investigó su presencia en 62 pacientes odontológicos de ambos sexos, edad promedio 35 años. Las muestras, tomadas de placas supragingival, colocadas en 0,3 ml de caldo tioglicolato, fueron cultivadas dentro de las 12 h en agar Mueller-Hinton con 5-7 por ciento de sangre de oveja y suplemento antibiótico e incubadas a 37§C en microaerofilia 5-7 días. Las colonias típicas se identificaron por gram, ureasa, oxidasa y catalasa. H. pylori fue detectado en un paciente de 15 años que padecía acidez gástrica (índice de positividad 1,61 por ciento). El medio utilizado facilitó la recuperación del agente desde una muestra abundante en gérmenes. No se aisló H. pylori del mismo paciente 12 meses después, sugiriendo un pasaje transitorio por reflujo gástrico o adquisición de la bacteria de una fuente exógena

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Se investigó la presencia de Helicobacter pylori en 50 pacientes con trastornos gastroduodenales que concurrieron a dos centros de salud de la ciudad de San Luis. De cada paciente se tomaron cuatro muestras de biopsia de mucosa de antro gástrico, dos de ellas destinadas al estudio histológico y dos al análisis bacteriológico: observación al Gram, prueba de ureasa y cultivo. Helicobacter pylori se detectó en 38 (76 por ciento) de los pacientes mediante el estudio histológico y en 30 (60 por ciento) por la tinción de Gram. De estos últimos, 28 (93 por ciento) dieron positiva la prueba de ureasa coincidiendo con un número significativo de bacterias. El 80 por ciento (24/30) de las muestras positivas al Gram mostró un buen desarrollo microbiano en los medios de cultivo de Mueller-Hinton y de Skirrow indistintamente. Se recomienda la prueba de ureasa como una alternativa de diagnóstico: rápida, económica y efectiva cuando hay una cantidad suficiente de bacterias. (AU)

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RESUMEN

Se investigó la presencia de Helicobacter pylori en 50 pacientes con trastornos gastroduodenales que concurrieron a dos centros de salud de la ciudad de San Luis. De cada paciente se tomaron cuatro muestras de biopsia de mucosa de antro gástrico, dos de ellas destinadas al estudio histológico y dos al análisis bacteriológico: observación al Gram, prueba de ureasa y cultivo. Helicobacter pylori se detectó en 38 (76 por ciento) de los pacientes mediante el estudio histológico y en 30 (60 por ciento) por la tinción de Gram. De estos últimos, 28 (93 por ciento) dieron positiva la prueba de ureasa coincidiendo con un número significativo de bacterias. El 80 por ciento (24/30) de las muestras positivas al Gram mostró un buen desarrollo microbiano en los medios de cultivo de Mueller-Hinton y de Skirrow indistintamente. Se recomienda la prueba de ureasa como una alternativa de diagnóstico: rápida, económica y efectiva cuando hay una cantidad suficiente de bacterias.

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