ABSTRACT
In order to detect subclinical mastitis by means of California Mastitis Test and recounting of somatic cells, 163 cows from the dairies of San Luis city, Argentina, were examined. Seventy six individuals (46.6
) exhibited an inflammatory response ranging > or = 2+ grade and a cellular recounting value of > or = 5 x 10(5), data compatible with those of subclinical mastitis. Staphylococcus aureus was isolated from 39 (51.3
) cultures as estimated by the sum of the two last values listed in Table 1. Organisms were isolated by plating on brain heart infusion agar with 5
of sheep blood and on Baird-Parker media. One hundred and three S. aureus isolates recovered from 51 of 63 cows were characterized by coagulase activity by the tube method using human and bovine plasma; clumping factor; glucose and mannitol fermentation; thermonuclease (TNase), pigment, gelatinase, fibrinolysin, acetoin, hemolysin production; egg yolk, tellurite and catalase reaction and crystal violet types. All isolates were susceptible to cephalothin, clindamycin, methicillin, gentamycin and vancomycin; 94.1
were susceptible to chloramphenicol and 53.8
) were classified according to Hájek and Marsálek scheme as biotype C (bovine and ovine ecovar), 33 isolates (32.0
) were classified as biotype B (swine and poultry ecovar); 1 isolated (0.9
) as intermediate between B and D; 5 isolates (4.8
) as biotype A (human ecovar) and 1 isolated (0.9
) as biotype D (ecovar silvestres spp) (Table 2). Production of enterotoxins A to E and toxic shock syndrome toxin-1 (TSST-1) was determined by the optimal susceptibility plate method on 27 isolates (26.2
) which were coagulase 3+ to 4+ and TNase highly positive. None of them produced enterotoxins including TSST-1. The subclinical mastitis data and the prevalence of S. aureus coincide with those of other authors, both from Argentina and from other countries.
ABSTRACT
In order to detect subclinical mastitis by means of California Mastitis Test and recounting of somatic cells, 163 cows from the dairies of San Luis city, Argentina, were examined. Seventy six individuals (46.6
) exhibited an inflammatory response ranging > or = 2+ grade and a cellular recounting value of > or = 5 x 10(5), data compatible with those of subclinical mastitis. Staphylococcus aureus was isolated from 39 (51.3
) cultures as estimated by the sum of the two last values listed in Table 1. Organisms were isolated by plating on brain heart infusion agar with 5
of sheep blood and on Baird-Parker media. One hundred and three S. aureus isolates recovered from 51 of 63 cows were characterized by coagulase activity by the tube method using human and bovine plasma; clumping factor; glucose and mannitol fermentation; thermonuclease (TNase), pigment, gelatinase, fibrinolysin, acetoin, hemolysin production; egg yolk, tellurite and catalase reaction and crystal violet types. All isolates were susceptible to cephalothin, clindamycin, methicillin, gentamycin and vancomycin; 94.1
were susceptible to chloramphenicol and 53.8
) were classified according to Hájek and Marsálek scheme as biotype C (bovine and ovine ecovar), 33 isolates (32.0
) were classified as biotype B (swine and poultry ecovar); 1 isolated (0.9
) as intermediate between B and D; 5 isolates (4.8
) as biotype A (human ecovar) and 1 isolated (0.9
) as biotype D (ecovar silvestres spp) (Table 2). Production of enterotoxins A to E and toxic shock syndrome toxin-1 (TSST-1) was determined by the optimal susceptibility plate method on 27 isolates (26.2
) which were coagulase 3+ to 4+ and TNase highly positive. None of them produced enterotoxins including TSST-1. The subclinical mastitis data and the prevalence of S. aureus coincide with those of other authors, both from Argentina and from other countries.
ABSTRACT
Se estudió la acción bacteriostática ejercida por chalconas naturales (2',4'-dihidroxichalcona y 2'-hidroxi-4'-metoxichalcona) y de síntesis (chalcona, 2'-hidroxicalcona, 2'4-dihidroxichalcona y 2'-hidroxi-4-metoxichalcona) sobre Staphylococcus aureus (cepa ATCC 25 923). Se determinó la influencia de la concentración de la natureza y posición de los sustituyentes de las drogas empleadas sobre la tasa de crecimiento específica del germen. Los ensayos cualitativos se hicieron en placas de agar nutritivo y mostraron la acción inhibitoria de chalcona y sus derivados dihidroxilados. Los resultados obtenidos distiguen el potente efecto bacteriostático de 2',4'-dihidroxichalcona y 2',4'-dihidrochalcona que en bajas concentraciones provocaron inhibición total en el crecimiento del microorganismo, de las otras chalconas estudiadas que solamente disminuyeron la tasa de crecimiento específica del germe hasta un valor límite. Se observa que la presencia de un grupo oxihidrilo en el anillo A o B de la 2'-hidroxichalcona potencia su actividad bacteriostática siendo este efecto más pronunciado en la posición 4'(anillo A) respecto de la posición 4 (anillo B). La introducción de un grupo metoxilo en la estructura de la 2'-hidroxichalcona produce un decrecimiento de su potencia inhibitoria
Subject(s)
Chalcone/pharmacologyABSTRACT
El botulismo del lactante es una toxiinfeccion producida por la germinacion y toxinogenesis de Clostridium botulinum en el intestino. La presente exposicion es una revisor de la literatura general publicada desde que se reconocio esta entidad a partir de 1976, incluyendo ademas el aporte de una investigacion realizada por los autores. Se decriben formas clinicas, epidemiologia y finalmente se hace referencia a diagnostico y tratamiento