[Diagnosis of entero-invasive Escherichia coli associated with diarrhea]. / Diagnóstico de Escherichia coli enteroinvasiva asociada a diarrea.

Sixteen Escherichia coli strains isolated from diarrhea patients, characterized as enteroinvasive (EIEC) by the keratoconjunctivitis test (Sereny test), and 15 non-EIEC strains, were studied. The aim of this study was to establish a possible correlation between the Sereny test and several other tests as enzyme-linked immunosorbent assay (ELISA) and biochemical markers, which are more easily accessible to general practice laboratories. Strains were assayed for the virulence marker antigen (the outer membrane proteins) by direct ELISA, biochemical tests, antimicrobial susceptibility profile and serotyping. Mean optical density (OD) values in the ELISA were 2.018 +/- 0.336 for EIEC strains, and 0.569 +/- 0.283 for non-EIEC strains. Difference between the OD values of the two groups was found to be significant at p < 0.01 by the one-tailed Student's test. One (6.2%) of the 16 Sereny test-positive strains was negative by ELISA. Considered as a group, the EIEC strains are rather heterogeneous in their biochemical characteristics. Lysine decarboxylase test appeared as the most relevant assay, since all EIEC strains were negative for this enzyme, whereas 66.7% of non-EIEC strains were positive. Other helpful tests performed for strain characterization were: gas production from glucose and from glycerol, sucrose and salicin fermentation, and esculin hydrolysis (p < 0.01). However, strains behaviour was variable with these tests. Differences between both groups of strains with regard to mucate utilization and dulcitol fermentation was significative only to a 5% level. Antibiotic sensitivity patterns showed differences between EIEC and non-EIEC strains: 37.5% of the former vs 80% of the latter, were resistant to at least four of the antibiotics tested.(ABSTRACT TRUNCATED AT 250 WORDS)

Diagnóstico de Escherichia coli enteroinvasiva asociada a diarrea / [Diagnosis of entero-invasive Escherichia coli associated with diarrhea]

Sixteen Escherichia coli strains isolated from diarrhea patients, characterized as enteroinvasive (EIEC) by the keratoconjunctivitis test (Sereny test), and 15 non-EIEC strains, were studied. The aim of this study was to establish a possible correlation between the Sereny test and several other tests as enzyme-linked immunosorbent assay (ELISA) and biochemical markers, which are more easily accessible to general practice laboratories. Strains were assayed for the virulence marker antigen (the outer membrane proteins) by direct ELISA, biochemical tests, antimicrobial susceptibility profile and serotyping. Mean optical density (OD) values in the ELISA were 2.018 +/- 0.336 for EIEC strains, and 0.569 +/- 0.283 for non-EIEC strains. Difference between the OD values of the two groups was found to be significant at p < 0.01 by the one-tailed Student’s test. One (6.2

) of the 16 Sereny test-positive strains was negative by ELISA. Considered as a group, the EIEC strains are rather heterogeneous in their biochemical characteristics. Lysine decarboxylase test appeared as the most relevant assay, since all EIEC strains were negative for this enzyme, whereas 66.7

of non-EIEC strains were positive. Other helpful tests performed for strain characterization were: gas production from glucose and from glycerol, sucrose and salicin fermentation, and esculin hydrolysis (p < 0.01). However, strains behaviour was variable with these tests. Differences between both groups of strains with regard to mucate utilization and dulcitol fermentation was significative only to a 5

level. Antibiotic sensitivity patterns showed differences between EIEC and non-EIEC strains: 37.5

of the former vs 80

of the latter, were resistant to at least four of the antibiotics tested.(ABSTRACT TRUNCATED AT 250 WORDS)

Diagnóstico de Escherichia coli enteroinvasiva asociada a diarrea. / [Diagnosis of entero-invasive Escherichia coli associated with diarrhea]

Sixteen Escherichia coli strains isolated from diarrhea patients, characterized as enteroinvasive (EIEC) by the keratoconjunctivitis test (Sereny test), and 15 non-EIEC strains, were studied. The aim of this study was to establish a possible correlation between the Sereny test and several other tests as enzyme-linked immunosorbent assay (ELISA) and biochemical markers, which are more easily accessible to general practice laboratories. Strains were assayed for the virulence marker antigen (the outer membrane proteins) by direct ELISA, biochemical tests, antimicrobial susceptibility profile and serotyping. Mean optical density (OD) values in the ELISA were 2.018 +/- 0.336 for EIEC strains, and 0.569 +/- 0.283 for non-EIEC strains. Difference between the OD values of the two groups was found to be significant at p < 0.01 by the one-tailed Students test. One (6.2

) of the 16 Sereny test-positive strains was negative by ELISA. Considered as a group, the EIEC strains are rather heterogeneous in their biochemical characteristics. Lysine decarboxylase test appeared as the most relevant assay, since all EIEC strains were negative for this enzyme, whereas 66.7

of non-EIEC strains were positive. Other helpful tests performed for strain characterization were: gas production from glucose and from glycerol, sucrose and salicin fermentation, and esculin hydrolysis (p < 0.01). However, strains behaviour was variable with these tests. Differences between both groups of strains with regard to mucate utilization and dulcitol fermentation was significative only to a 5

level. Antibiotic sensitivity patterns showed differences between EIEC and non-EIEC strains: 37.5

of the former vs 80

of the latter, were resistant to at least four of the antibiotics tested.(ABSTRACT TRUNCATED AT 250 WORDS)

[Latin American regional reference materials for porcine heparin and bovine heparin]. / Materiales regionales latinoamericanos de referencia de heparina porcina y heparina bovina.

In agreement with the Regional Programme of Reference Materials of the Panamerican Health Organization the Instituto Nacional de Farmacología y Bromatología of Buenos Aires designed a study for the calibration of a Reference Material for Heparin, porcine, mucosal and a Reference Material for Heparin, bovine, mucosal. The assay methods used in this study were those described in the United States Pharmacopeia XXI Ed and British Pharmacopoeia 1980, Addendum 1983. The overall combined potency estimates of both heparin in preparations relative to 4th Int.St. was 1633.83 UI/ampoule (95% confidence limits 1609.70-1657.96 UI/ampoule) for porcine heparin and 1332.31 UI/ampoule (95% confidence limits, 1302.31-1361.77 UI/ampoule) for bovine heparin. The assigned unitage was 1630 UI/ampoule for the porcine Reference Material and 1330 UI/ampoule for the bovine Reference Material.

Relative risk of colorectal cancer after cholecystectomy. A multicentre case-control study.

The relative risk of developing colorectal cancer after cholecystectomy was assessed retrospectively in 493 patients with colorectal cancer (239 women, 254 men). The results were compared with a control group of patients matched for sex and age. The overall relative risk was 0.7 (90% confidence interval, 0.7-0.8). However, when the data were analysed for site significant differences were seen. In the caecum and ascending colon the relative risk of developing colorectal cancer after cholecystectomy was 2.8 (90% confidence interval, 1.0-9.4). In the rectum the relative risk was only 0.3 (90% confidence interval, 0.2-0.6) in both sexes. The results suggest a relative increased risk of developing right-sided colon cancer after cholecystectomy in women. However, they only partially support the hypothesis that prior cholecystectomy increases the relative risk of developing colorectal cancer in view of the data relating to the rectum.

[Numerical taxonomy of the genus Bacillus]. / Taxonomía numérica del género Bacillus.

Eighty-one morphologic and biochemical features of seventy Bacillus strains were studied. Techniques of Numerical Taxonomy were used for this purpose. One method of coding and four others of clustering methods were used. Clustering methods were: weighted an unweighted pair-groups methods using arithmetic averages (WPGMA and UPGMA, respectively) and those of simple and complete linkage. With this methodology four dendrograms were obtained. The highest cophenetic correlation coefficient (0,718) was obtained from UPGMA. With UPGMA a classification in eleven groups and fourteen subgroups was obtained. Group was defined as the cluster of strains linked with similarity coefficients greater than 0.700 and subgroup as the cluster of strains linked with similarity coefficients greater than 0.800. It is important to take into account that in WPGMA dendrogram a very similar distribution was observed. As in classical taxonomy, the characteristic morphologic and physiological variabilities of the genus Bacillus were observed.

Taxonomía numérica del género Bacillus. / [Numerical taxonomy of the genus Bacillus]

Eighty-one morphologic and biochemical features of seventy Bacillus strains were studied. Techniques of Numerical Taxonomy were used for this purpose. One method of coding and four others of clustering methods were used. Clustering methods were: weighted an unweighted pair-groups methods using arithmetic averages (WPGMA and UPGMA, respectively) and those of simple and complete linkage. With this methodology four dendrograms were obtained. The highest cophenetic correlation coefficient (0,718) was obtained from UPGMA. With UPGMA a classification in eleven groups and fourteen subgroups was obtained. Group was defined as the cluster of strains linked with similarity coefficients greater than 0.700 and subgroup as the cluster of strains linked with similarity coefficients greater than 0.800. It is important to take into account that in WPGMA dendrogram a very similar distribution was observed. As in classical taxonomy, the characteristic morphologic and physiological variabilities of the genus Bacillus were observed.

[Cholecystectomy and colorectal adenocarcinoma]. / Colecistectomía y adenocarcinoma colorectal.

The relative risk of developing colorectal cancer after cholecystectomy was investigated retrospectively in 124 patients with colorectal cancer, 17 patients of which had undergone previous cholecystectomy. Another 124 patients without colorectal cancer were matched for sex and age; 19 patients of which had undergone previous cholecystectomy. Disregarding sex and cancer location the relative risk was 0.87 with a 90% confidential interval from 0.43 to 1.73. On the other hand considering cancer location the relative risk of suffering right-sided hemicolon cancer was 7 with a 90% confidential interval from 1.12 to 155.46 (P less than 0.05). The hypothesis that cholecystectomy increases the risk of suffering right-sided hemicolon adenocarcinoma however requires further evaluation.

Colecistectomia y adenocarcinoma colorectal. / Cholecystectomy and colorectal adenocarcinoma

El riesgo relativo a padecer de cancer colorectal despues de la colecistectomia, se investigo de manera retrospectiva en 124 pacientes con cancer intestinal, de los cuales 17 habian sido previamente colecistectomizados. El mismo numero de pacientes, sin cancer colorectal, se los apareo como controles segun edad y sexo, de los cuales 19 habian sido previamente colecistectomizados. El riesgo relativo sin discriminar sexo ni ubicacion del cancer fue de 0.87 con un intervalo confidencial del 90% de 0.43 a 1.73; en cambio al considerar la localizacion del cancer, el riesgo relativo para el cancer del H.D. fue de 7, con un intervalo confidencial del 90% de 1.12 a 155.46 (P < 0.05). La hipotesis que la colecistectomia aumente el riesgo a padecer de adenocarcinoma del hemicolon derecho necesita futuras investigaciones

Colecistectomía y adenocarcinoma colorectal. / [Cholecystectomy and colorectal adenocarcinoma]

The relative risk of developing colorectal cancer after cholecystectomy was investigated retrospectively in 124 patients with colorectal cancer, 17 patients of which had undergone previous cholecystectomy. Another 124 patients without colorectal cancer were matched for sex and age; 19 patients of which had undergone previous cholecystectomy. Disregarding sex and cancer location the relative risk was 0.87 with a 90

confidential interval from 0.43 to 1.73. On the other hand considering cancer location the relative risk of suffering right-sided hemicolon cancer was 7 with a 90

confidential interval from 1.12 to 155.46 (P less than 0.05). The hypothesis that cholecystectomy increases the risk of suffering right-sided hemicolon adenocarcinoma however requires further evaluation.

Colecistectomia y adenocarcinoma colorectal. / Cholecystectomy and colorectal adenocarcinoma

El riesgo relativo a padecer de cancer colorectal despues de la colecistectomia, se investigo de manera retrospectiva en 124 pacientes con cancer intestinal, de los cuales 17 habian sido previamente colecistectomizados. El mismo numero de pacientes, sin cancer colorectal, se los apareo como controles segun edad y sexo, de los cuales 19 habian sido previamente colecistectomizados. El riesgo relativo sin discriminar sexo ni ubicacion del cancer fue de 0.87 con un intervalo confidencial del 90% de 0.43 a 1.73; en cambio al considerar la localizacion del cancer, el riesgo relativo para el cancer del H.D. fue de 7, con un intervalo confidencial del 90% de 1.12 a 155.46 (P < 0.05). La hipotesis que la colecistectomia aumente el riesgo a padecer de adenocarcinoma del hemicolon derecho necesita futuras investigaciones

[Simplified preliminary identification of some species of Clostridium]. / Identificación preliminar simplificada de algunas especies de Clostridium.

A dichotomous key is proposed for the identification of eight species of Clostridium: Clostridium botulinum, C. butyricum, C. haemolyticum, C. histolyticum, C. paraperfringens, C. perfringens, C. sporogenes y C. subterminale, on the basis of the Gram staining, catalase production, growth on nutrient agar, glucose utilization, motility test, gelatin hydrolysis, lecithinase production, human blood hemolysis and the test of mice toxicity.

[Numerical taxonomy of gram-positive anaerobic bacilli]. / Taxonomia numérica de bacilos gram positivos anaerobios.

Numerical Taxonomy's techniques were employed on twenty one anaerobic Gram positive bacilli strains taking account of eighty morphologic and biochemical features. Two methods of coding (weighted and non weighted) and four clustering methods (unweighted pair-group method using arithmetic averages; weighted pair-group method using arithmetic averages; single linkage and complete linkage) were used. Eight dendrograms were obtained and they showed that C. haemolyticum (strains 1, 2, 4, 7); C. subterminale (strains 8, 19); C. botulinum (strain 14) and C. sporogenes (strain 15) belong to a different group than the other strains. Another group would be formed with C. perfringens (strains 3, 5, 6, 12, 16, 21) and C. paraperfringens (strains 9, 10, 11). Of the remaining strains the two classified as Propionibacterium acnes (strains 17, 18) have a very high degree of agreement. C. histolyticum (strain 20) adjoins at a very low level, while C. butyricum (strain 13) shows a unfixed behaviour. The dendrograms display a disposition according with Classical Taxonomy.

Taxonomia numerica de bacilos gram positivos anaerobios. / Numerical taxonomy of gram-positive anaerobic bacilli

Se estudiaron por taxonomia numerica 21 cepas de bacilos anaerobios Gram positivos empleandose ochenta caracteres morfologicos y bioquimicos. Se aplicaron dos metodos de codificacion (pesado y no pesado) y cuatro de agrupamiento (metodo de los pares no pesados usando promedios aritmeticos, metodo de ligamiento simple y metodo de ligamiento completo). Se obtuvieron ocho dendrogramas que muestran que Clostridium haemolyticum (cepas 1, 2, 4 y 7), C. subterminale (cepas 8 y 19), C. botulinum (cepa 14) y C. sporogenes (cepas 15) forman un grupo diferenciable de las restantes cepas. Outro grupo estaria constituido por C. perfringens (cepas 3, 5, 6, 12, 16 y 21) y C. paraperfringens (cepas 9, 10 y 11). De las cuatro cepas restantes la dos correspondientes a Propionibacterium acnes (cepas 17 y 18) guardan entre si una estrecha similitud. C. histolyticum (cepa 20) se une luego a un nivel muy inferior, mientras que C. butyricum (cepa 13) muestra un comportamiento variable. El ordenamiento obtenido es concordante con el dado por la taxonomia clasica

Identificacion preliminar simplificada de algunas especies de Clostridium / Simplified preliminary identification of some species of Clostridium

Se propone una clave dicotomica para la identificacion de ocho especies de Clostridium: Clostridium botulinum, C. butyricum, C. haemolyticum, C. histolyticum, C.paraperfringens, C. perfringens, C. sporogenes y C. subterminale, la cual requiere observacion microscopica por medio de la coloracion de Gram y ocho pruebas: produccion de catalasas, crecimiento en agar nutritivo, fermentacion de glucosa, movilidad, hidrolisis de gelatina, produccion de lecitinasas, hemolisis en agar sangre humana y la prueba de toxicidad en raton

Taxonomia numérica de bacilos gram positivos anaerobios. / [Numerical taxonomy of gram-positive anaerobic bacilli]

Numerical Taxonomys techniques were employed on twenty one anaerobic Gram positive bacilli strains taking account of eighty morphologic and biochemical features. Two methods of coding (weighted and non weighted) and four clustering methods (unweighted pair-group method using arithmetic averages; weighted pair-group method using arithmetic averages; single linkage and complete linkage) were used. Eight dendrograms were obtained and they showed that C. haemolyticum (strains 1, 2, 4, 7); C. subterminale (strains 8, 19); C. botulinum (strain 14) and C. sporogenes (strain 15) belong to a different group than the other strains. Another group would be formed with C. perfringens (strains 3, 5, 6, 12, 16, 21) and C. paraperfringens (strains 9, 10, 11). Of the remaining strains the two classified as Propionibacterium acnes (strains 17, 18) have a very high degree of agreement. C. histolyticum (strain 20) adjoins at a very low level, while C. butyricum (strain 13) shows a unfixed behaviour. The dendrograms display a disposition according with Classical Taxonomy.

Identificación preliminar simplificada de algunas especies de Clostridium. / [Simplified preliminary identification of some species of Clostridium]

A dichotomous key is proposed for the identification of eight species of Clostridium: Clostridium botulinum, C. butyricum, C. haemolyticum, C. histolyticum, C. paraperfringens, C. perfringens, C. sporogenes y C. subterminale, on the basis of the Gram staining, catalase production, growth on nutrient agar, glucose utilization, motility test, gelatin hydrolysis, lecithinase production, human blood hemolysis and the test of mice toxicity.

Taxonomia numerica de bacilos gram positivos anaerobios. / Numerical taxonomy of gram-positive anaerobic bacilli

Se estudiaron por taxonomia numerica 21 cepas de bacilos anaerobios Gram positivos empleandose ochenta caracteres morfologicos y bioquimicos. Se aplicaron dos metodos de codificacion (pesado y no pesado) y cuatro de agrupamiento (metodo de los pares no pesados usando promedios aritmeticos, metodo de ligamiento simple y metodo de ligamiento completo). Se obtuvieron ocho dendrogramas que muestran que Clostridium haemolyticum (cepas 1, 2, 4 y 7), C. subterminale (cepas 8 y 19), C. botulinum (cepa 14) y C. sporogenes (cepas 15) forman un grupo diferenciable de las restantes cepas. Outro grupo estaria constituido por C. perfringens (cepas 3, 5, 6, 12, 16 y 21) y C. paraperfringens (cepas 9, 10 y 11). De las cuatro cepas restantes la dos correspondientes a Propionibacterium acnes (cepas 17 y 18) guardan entre si una estrecha similitud. C. histolyticum (cepa 20) se une luego a un nivel muy inferior, mientras que C. butyricum (cepa 13) muestra un comportamiento variable. El ordenamiento obtenido es concordante con el dado por la taxonomia clasica

Identificacion preliminar simplificada de algunas especies de Clostridium / Simplified preliminary identification of some species of Clostridium

Se propone una clave dicotomica para la identificacion de ocho especies de Clostridium: Clostridium botulinum, C. butyricum, C. haemolyticum, C. histolyticum, C.paraperfringens, C. perfringens, C. sporogenes y C. subterminale, la cual requiere observacion microscopica por medio de la coloracion de Gram y ocho pruebas: produccion de catalasas, crecimiento en agar nutritivo, fermentacion de glucosa, movilidad, hidrolisis de gelatina, produccion de lecitinasas, hemolisis en agar sangre humana y la prueba de toxicidad en raton