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1.
Zentralbl Bakteriol ; 287(1-2): 61-6, 1998 Jan.
Article de Anglais | MEDLINE | ID: mdl-9532265

RÉSUMÉ

Five cases of infant botulism which occurred during the period from May 1995 to May 1996 in San Luis, Argentina, are reported. Infant botulism was confirmed in all patients by isolation of Clostridium botulinum type A from stool culture and by the toxin assay. Toxin was found in the serum of one of them. All patients required hospitalization with treatment consisting of supportive especially respiratory and nutritional care. At the time of discharge from the hospital, three patients had a good recovery, although two of them had mild difficulties in sucking or constipation. C. botulinum was not detected in samples of honey which had been given to two of the patients.


Sujet(s)
Botulisme/diagnostic , Clostridium botulinum/isolement et purification , Argentine/épidémiologie , Toxines botuliniques/sang , Toxines botuliniques/isolement et purification , Botulisme/sang , Botulisme/épidémiologie , Femelle , Humains , Nourrisson , Mâle
2.
Zentralbl Bakteriol ; 286(3): 413-9, 1997 Oct.
Article de Anglais | MEDLINE | ID: mdl-9361387

RÉSUMÉ

The strain G89HT of Clostridium argentinense obtained by culture selection of the prototype G89 strain producing high titers of type G botulinal toxin was studied. Its cultural, biochemical and toxigenic characteristics and the presence of plasmids were tested. Both strains showed similar physiological features and carried a 83 MDa plasmid. A 170 MDa plasmid was also recognized in the G89HT strain. Notably, this strain was better sporulating and showed a higher toxigenicity than the prototype G89 C. argentinense strain. These two characteristics might permit a long term storage and perhaps yield high antitoxin titres.


Sujet(s)
Toxines botuliniques/métabolisme , Clostridium/métabolisme , Protéines bactériennes/analyse , Clostridium/croissance et développement , Clostridium/pathogénicité , Milieux de culture/métabolisme , Tests de neutralisation , Plasmides/génétique , Plasmides/isolement et purification , Spores bactériens/génétique , Spores bactériens/croissance et développement , Spores bactériens/métabolisme , Trypsine/métabolisme , Virulence/génétique
3.
Zentralbl Bakteriol ; 277(2): 161-9, 1992 Jul.
Article de Anglais | MEDLINE | ID: mdl-1520974

RÉSUMÉ

Culture conditions were optimized for toxin production of Clostridium botulinum type G, the last toxigenic serotype described. Six factorial experiments were performed to assess the effect of medium composition (nutrients, metal ions, sterile soil, pH), incubation conditions (time, temperature and anaerobiosis) and associated microorganisms (Bacillus subtilis, Lactobacillus plantarum) on the toxinogenesis of C. botulinum type G. A significant (4 to 10 fold) improvement of toxin production was obtained by using an optimized medium (3% proteose-peptone, 0.5% trypticase, 1.1% glucose, 0.5% yeast extract, adjusted to pH 8.0) and incubation of the culture for 12 days at 26 degrees C in a nitrogen atmosphere.


Sujet(s)
Toxines botuliniques/biosynthèse , Clostridium botulinum/métabolisme , Anaérobiose , Milieux de culture , Concentration en ions d'hydrogène , Température
4.
Rev Argent Microbiol ; 24(2): 73-80, 1992.
Article de Espagnol | MEDLINE | ID: mdl-1298016

RÉSUMÉ

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% to G penicillin. Sixty three isolates (61.1%) 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.


Sujet(s)
Mammite bovine/microbiologie , Infections à staphylocoques/médecine vétérinaire , Staphylococcus aureus/isolement et purification , Animaux , Argentine/épidémiologie , Bovins , Résistance microbienne aux médicaments , Femelle , Incidence , Mammite bovine/épidémiologie , Lait/microbiologie , Prévalence , Infections à staphylocoques/épidémiologie , Infections à staphylocoques/microbiologie , Staphylococcus aureus/classification , Staphylococcus aureus/effets des médicaments et des substances chimiques
5.
Rev. argent. microbiol ; Rev. argent. microbiol;24(2): 73-80, 1992 Apr-Jun.
Article de Espagnol | BINACIS | ID: bin-51163

RÉSUMÉ

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


to G penicillin. Sixty three isolates (61.1


) 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.

6.
Rev. argent. microbiol ; Rev. argent. microbiol;24(2): 73-80, 1992 Apr-Jun.
Article de Espagnol | BINACIS | ID: bin-38066

RÉSUMÉ

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


to G penicillin. Sixty three isolates (61.1


) 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.

7.
Rev. argent. microbiol ; Rev. argent. microbiol;24(2): 73-80, 1992 Apr-Jun.
Article de Espagnol | LILACS-Express | LILACS, BINACIS | ID: biblio-1171564

RÉSUMÉ

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.

8.
Rev. argent. microbiol ; Rev. argent. microbiol;24(2): 73-80, 1992 Apr-Jun.
Article de Espagnol | LILACS-Express | LILACS, BINACIS | ID: biblio-1171572

RÉSUMÉ

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.

9.
Rev Argent Microbiol ; 22(3): 142-5, 1990.
Article de Espagnol | MEDLINE | ID: mdl-2102013

RÉSUMÉ

Thirty nine milk handlers from a factory of dairy products in the Province of Buenos Aires were examined for their nasal carriage of S. aureus strains capable of producing toxic-shock-syndrome toxin-1 (TSST-1). In addition, chance samples of handled foods, crude milk and milky fermented derivates (MFD) were studied. Strain isolation was made on Mannitol Salt Agar and on Baird-Parker Agar. Typical colonies were identified by their biochemical properties. Cultures that were found to be S. aureus were selected for analysis of the TSST-1 production. Eight milk handlers (20.5%) were carriers of S. aureus strains. Seven isolates (87.5%) were classified as biotype A (human ecovar) and 1(12.5%) was classified as biotype B (swine and poultry ecovar). Three out of 8 S. aureus biotype A isolates (37.5%), produced TSST-1. Taking into account the number of milk food handlers sampled (39), the carried rate of toxigenic strains was 7.6%. Three S. aureus strains were isolated from crude milk; 1(33.3%) was classified as biotype B and 2(66.6%) as biotype C (cattle and sheep ecovar). Thirteen S. aureus strains were isolated from MDF; 5(38.0%) were classified as biotype A, 1(7.7%) as belonging to biotype B and 7(53.8%) as belonging to biotype C. None of them had the ability to produce TSST-1.


Sujet(s)
Toxines bactériennes , État de porteur sain/épidémiologie , Produits laitiers , Entérotoxines/isolement et purification , Contamination des aliments , Manipulation des aliments , Microbiologie alimentaire , Infections à staphylocoques/transmission , Staphylococcus aureus/isolement et purification , Superantigènes , Animaux , Argentine/épidémiologie , Humains , Lait , Fosse nasale/microbiologie , Staphylococcus aureus/métabolisme
10.
Rev. argent. microbiol ; Rev. argent. microbiol;22(3): 142-5, 1990 Jul-Sep.
Article de Espagnol | BINACIS | ID: bin-51569

RÉSUMÉ

Thirty nine milk handlers from a factory of dairy products in the Province of Buenos Aires were examined for their nasal carriage of S. aureus strains capable of producing toxic-shock-syndrome toxin-1 (TSST-1). In addition, chance samples of handled foods, crude milk and milky fermented derivates (MFD) were studied. Strain isolation was made on Mannitol Salt Agar and on Baird-Parker Agar. Typical colonies were identified by their biochemical properties. Cultures that were found to be S. aureus were selected for analysis of the TSST-1 production. Eight milk handlers (20.5


) were carriers of S. aureus strains. Seven isolates (87.5


) were classified as biotype A (human ecovar) and 1(12.5


) was classified as biotype B (swine and poultry ecovar). Three out of 8 S. aureus biotype A isolates (37.5


), produced TSST-1. Taking into account the number of milk food handlers sampled (39), the carried rate of toxigenic strains was 7.6


. Three S. aureus strains were isolated from crude milk; 1(33.3


) was classified as biotype B and 2(66.6


) as biotype C (cattle and sheep ecovar). Thirteen S. aureus strains were isolated from MDF; 5(38.0


) were classified as biotype A, 1(7.7


) as belonging to biotype B and 7(53.8


) as belonging to biotype C. None of them had the ability to produce TSST-1.

11.
Rev Argent Microbiol ; 19(2): 47-54, 1987.
Article de Espagnol | MEDLINE | ID: mdl-3503310

RÉSUMÉ

Staphylococcus sp was investigated in the female lower genital tract of 102 healthy women aged between 18 and 48 years in San Luis, Argentina. Three hundred and six samples were obtained from labia, introitus and vagina (posterior fornix). Samples were plated on sheep blood, mannitol salt and Baird-Parker media. Strains were identified by tube coagulase test; thermonuclease, fibrinolysin, pigment and hemolysin production; glucose and mannitol utilization and novobiocin sensitivity. Antibiotic susceptibility was assayed. Strains were examined for their ability to produce staphylococcal enterotoxins (SE) and toxic shock syndrome toxin-1 (TSST-1). Fourteen women (13.7%) had S. aureus in one or more samples: 10.7% labia, 3.9% introitus and 3.9% vaginal. All strains were sensitive to cephalotin, clindamycin, erythromycin, gentamycin and chloramphenicol; 21.0% were intermediate to methicillin; 15.7% were resistant to methicillin, 94.7% to penicillin and 21.0% to tetracycline. Three strains (15.7%) produced SEB, three (15.7%) SED, one (5.7%) SEC and three (15.7%) TSST-1. Only one strain (5.7%) produced both SEB and TSST-1. All strains produced hemolysins. Coagulase negative staphylococci were found in 40.1% of vaginal samples: S. epidermidis (32.2%) and S. saprophyticus (9.8%) were identified.


Sujet(s)
Toxines bactériennes , Entérotoxines/analyse , Staphylococcus aureus/isolement et purification , Superantigènes , Vagin/microbiologie , Vulve/microbiologie , Adolescent , Adulte , Femelle , Humains , Tests de sensibilité microbienne , Adulte d'âge moyen , Staphylococcus aureus/métabolisme
12.
Rev. argent. microbiol ; Rev. argent. microbiol;19(2): 47-54, 1987 Apr-Jun.
Article de Espagnol | BINACIS | ID: bin-52552

RÉSUMÉ

Staphylococcus sp was investigated in the female lower genital tract of 102 healthy women aged between 18 and 48 years in San Luis, Argentina. Three hundred and six samples were obtained from labia, introitus and vagina (posterior fornix). Samples were plated on sheep blood, mannitol salt and Baird-Parker media. Strains were identified by tube coagulase test; thermonuclease, fibrinolysin, pigment and hemolysin production; glucose and mannitol utilization and novobiocin sensitivity. Antibiotic susceptibility was assayed. Strains were examined for their ability to produce staphylococcal enterotoxins (SE) and toxic shock syndrome toxin-1 (TSST-1). Fourteen women (13.7


) had S. aureus in one or more samples: 10.7


labia, 3.9


introitus and 3.9


vaginal. All strains were sensitive to cephalotin, clindamycin, erythromycin, gentamycin and chloramphenicol; 21.0


were intermediate to methicillin; 15.7


were resistant to methicillin, 94.7


to penicillin and 21.0


to tetracycline. Three strains (15.7


) produced SEB, three (15.7


) SED, one (5.7


) SEC and three (15.7


) TSST-1. Only one strain (5.7


) produced both SEB and TSST-1. All strains produced hemolysins. Coagulase negative staphylococci were found in 40.1


of vaginal samples: S. epidermidis (32.2


) and S. saprophyticus (9.8


) were identified.

13.
Rev Argent Microbiol ; 18(2): 63-7, 1986.
Article de Espagnol | MEDLINE | ID: mdl-3685383

RÉSUMÉ

Blood samples obtained from 256 workers of an abattoir were tested for brucellosis antibodies and 11.7% were found reactive. The highest rate was 44.2% among those who had contact with blood and viscera, and 26.1% among workers at slaughter section. Four tests were used: plaque agglutination (PA), tube agglutination (TA), card test (CT) and complement fixation (CF). The highest number of positive reactions was obtained by the PA and TA tests, with a complete coincidence in both results. When both test titers were the same or less than 50 IU, CF and CT yielded less percentage of positive results. When titers were higher than 50 IU, CT but CF showed concordance between the results.


Sujet(s)
Abattoirs , Brucellose/immunologie , Maladies professionnelles/immunologie , Tests d'agglutination , Anticorps antibactériens/analyse , Argentine , Tests de fixation du complément , Humains , Professions
14.
Rev. argent. microbiol ; Rev. argent. microbiol;18(2): 63-7, 1986.
Article de Espagnol | BINACIS | ID: bin-52819

RÉSUMÉ

Blood samples obtained from 256 workers of an abattoir were tested for brucellosis antibodies and 11.7


were found reactive. The highest rate was 44.2


among those who had contact with blood and viscera, and 26.1


among workers at slaughter section. Four tests were used: plaque agglutination (PA), tube agglutination (TA), card test (CT) and complement fixation (CF). The highest number of positive reactions was obtained by the PA and TA tests, with a complete coincidence in both results. When both test titers were the same or less than 50 IU, CF and CT yielded less percentage of positive results. When titers were higher than 50 IU, CT but CF showed concordance between the results.

15.
Rev Argent Microbiol ; 17(1): 27-32, 1985.
Article de Espagnol | MEDLINE | ID: mdl-3870738

RÉSUMÉ

The bacteriostatic action exerted by natural chalcones (2',4'-dihydroxychalcone and 2'-hydroxy-4'-methoxychalcone) and by synthetic chalcones (chalcone, 2'-hydroxychalcone, 2'4-dihydroxychalcone and 2'-hydroxy-4-methoxychalcone) on Staphylococcus aureus (ATCC 25 923 Strain) was investigated. In addition, the influence of the concentration, nature and position of the substituents of the mentioned drugs on the specific growth rate of the germ was determined. Qualitative tests made on nutritive agar plates showed the inhibitory action of chalcone and its dihydroxyl derivatives. Quantitative experiments were made in nutritive broth at 33 degrees C, with permanent stirring (200 rpm), measuring the microbial growth by turbidimetry at 720 nm. The results distinguish the strong bacteriostatic effect of 2',4'-dihydroxychalcone and 2',4-dihydroxychalcone, which at low concentrations caused complete inhibition of microorganism growth, from the other chalcones studies which only reduced the up to a limiting value. The presence of an hydroxyl group in the A or B ring of 2'-hydroxychalcone increases its bacteriostatic activity, being this effect stronger at position 4' (ring A) than at position 4 (ring B). The introduction of a methoxy group into the 2'-hydroxychalcone structure causes a decrease of its inhibitory power.


Sujet(s)
Chalcone/pharmacologie , Propiophénones/pharmacologie , Staphylococcus aureus/effets des médicaments et des substances chimiques , Chalcone/synthèse chimique , Tests de sensibilité microbienne , Relation structure-activité
16.
Rev. argent. microbiol ; Rev. argent. microbiol;17(1): 27-32, 1985. tab
Article de Espagnol | LILACS | ID: lil-26826

RÉSUMÉ

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


Sujet(s)
Chalcone/pharmacologie
17.
Rev. argent. microbiol ; 17(1): 27-32, 1985. Tab
Article de Espagnol | BINACIS | ID: bin-33200

RÉSUMÉ

Se estudió la acción bacteriostática ejercida por chalconas naturales (2,4-dihidroxichalcona y 2-hidroxi-4-metoxichalcona) y de síntesis (chalcona, 2-hidroxicalcona, 24-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 (AU)


Sujet(s)
Chalcone/pharmacologie
18.
Rev. argent. microbiol ; Rev. argent. microbiol;17(1): 27-32, 1985.
Article de Espagnol | BINACIS | ID: bin-49143

RÉSUMÉ

The bacteriostatic action exerted by natural chalcones (2,4-dihydroxychalcone and 2-hydroxy-4-methoxychalcone) and by synthetic chalcones (chalcone, 2-hydroxychalcone, 24-dihydroxychalcone and 2-hydroxy-4-methoxychalcone) on Staphylococcus aureus (ATCC 25 923 Strain) was investigated. In addition, the influence of the concentration, nature and position of the substituents of the mentioned drugs on the specific growth rate of the germ was determined. Qualitative tests made on nutritive agar plates showed the inhibitory action of chalcone and its dihydroxyl derivatives. Quantitative experiments were made in nutritive broth at 33 degrees C, with permanent stirring (200 rpm), measuring the microbial growth by turbidimetry at 720 nm. The results distinguish the strong bacteriostatic effect of 2,4-dihydroxychalcone and 2,4-dihydroxychalcone, which at low concentrations caused complete inhibition of microorganism growth, from the other chalcones studies which only reduced the up to a limiting value. The presence of an hydroxyl group in the A or B ring of 2-hydroxychalcone increases its bacteriostatic activity, being this effect stronger at position 4 (ring A) than at position 4 (ring B). The introduction of a methoxy group into the 2-hydroxychalcone structure causes a decrease of its inhibitory power.

19.
Arch. argent. pediatr ; 82(3): 221-3, 1984.
Article de Espagnol | LILACS | ID: lil-22416

RÉSUMÉ

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


Sujet(s)
Botulisme
20.
Arch. argent. pediatr ; 82(3): 221-3, 1984.
Article de Espagnol | BINACIS | ID: bin-33823

RÉSUMÉ

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


Sujet(s)
Botulisme
SÉLECTION CITATIONS
DÉTAIL DE RECHERCHE