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Sample records for streptococcus constellatus agente

  1. Taxonomy of the Anginosus group of the genus Streptococcus and description of Streptococcus anginosus subsp. whileyi subsp. nov. and Streptococcus constellatus subsp. viborgensis subsp. nov

    DEFF Research Database (Denmark)

    Jensen, Anders; Hoshino, Tomonori

    2013-01-01

    The Anginosus group of the genus Streptococcus has been the subject of much taxonomic confusion, which has hampered the full appreciation of its clinical significance. The purpose of this study was to critically re-examine the taxonomy of the Anginosus group, with special attention to ?-haemolytic, Lancefield group C strains, using multilocus sequence analysis (MLSA) combined with 16S rRNA gene sequence and phenotypic analyses. Phylogenetic analysis of concatenated sequences of seven housekeeping genes previously used for examination of viridans streptococci distinguished seven distinct and coherent clusters in the Anginosus group. Analyses of 16S rRNA gene sequences and phenotypic characters supported the MLSA clustering and currently recognized taxa of the Anginosus group. Single gene analyses showed considerable allele sharing between species, thereby invalidating identification based on single-locus sequencing. Two novel clusters of ?-haemolytic, Lancefield group C strains within the Streptococcus constellatus and Streptococcus anginosus species and isolated from patients with sore throat showed sufficient phylogenetic distances from other clusters to warrant status as novel subspecies. The novel cluster within S. anginosus was identified as the previously recognized DNA homology cluster, DNA group 2. The names S. anginosus subsp. whileyi subsp. nov. (type strain CCUG 39159(T)?=?DSM 25818(T)?=?SK1267(T)) and S. constellatus subsp. viborgensis subsp. nov. (type strain SK1359(T)?=?CCUG 62387(T)?=?DSM 25819(T)) are proposed.

  2. Resistance of Streptococcus sanguis biofilms to antimicrobial agents

    DEFF Research Database (Denmark)

    Larsen, T; Fiehn, N E

    1996-01-01

    Bacteria living in biofilms as dental plaque on tooth surfaces are generally more resistant to antimicrobial agents than bacteria in batch culture normally used for in vitro susceptibility testing. In order to compare the resistance of free-living and surface-grown oral bacteria, the MIC of Streptococcus sanguis 804 and ATCC 10556 to amoxicillin, doxycycline and chlorhexidine was determined by a broth dilution method. Subsequently, S. sanguis biofilms established in an in vitro flow model were p...

  3. Streptococcus agalactie como agente etiológico de Doença Sexualmente Transmissível Streptococcus agalactie involved in the etiology of Sexually Transmitted Diseases

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    Marcos Noronha Frey

    2011-12-01

    Full Text Available O Streptococcus agalactie é um importante micro-organismo causador de doenças em gestantes, neonatos, idosos (maiores de 65 anos de idade, e portadores de doenças crônicas debilitantes, sendo um patógeno incomum em pacientes que não se enquadrem nestas faixas etárias ou perfil clínico (1-5, e, raramente, é descrito como agente causador de doenças sexualmente transmissíveis. Descrevemos o caso de um adulto jovem hígido de 19 anos, apresentando lesões ulceradas genitais e oral, assim como corrimento uretral e ocular, sugestivas de terem sido causadas pelo Streptococcus agalactie, e adquiridas através do contato sexual (doenças sexualmente transmissíveis.Streptococcus agalactiae is an important microorganism involved in a number of conditions in pregnant women, newborns, elderly people (over 65 years of age and individuals with chronic disabling illnesses. This pathogen is infrequently found among patients outside this age range or clinical profile(1-5 and is rarely reported in the etiology of sexually transmitted diseases. Here we describe a case of an otherwise healthy 19 year-old male, who presented with ulcerative genital and oral lesions in association with urethral and ocular discharge, suggestive of Streptococcus agalactiae infection acquired through sexual contact.

  4. In vitro susceptibility of Streptococcus mutans to chlorhexidine and six other antimicrobial agents.

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    Järvinen, H.; J Tenovuo; Huovinen, P

    1993-01-01

    The susceptibility of Streptococcus mutans to chlorhexidine and to six commonly used, systemic antibacterial agents (amoxicillin, cefuroxime, penicillin, sulfamethoxazole-trimethoprim, tetracycline, and erythromycin) was studied for 424 clinical isolates from 116 children and students. The MIC of chlorhexidine for all isolates was < or = 1 micrograms/ml. No resistance to the other antimicrobial agents was detected. Although widely exposed to various antimicrobial agents, S. mutans has remaine...

  5. Empiema pleural por Streptococcus grupo anginosus en un preescolar y revisión de la literatura: Case report and review Streptococcus anginosus pleural emphyema in a child

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    Paola Pidal M.

    2004-01-01

    Full Text Available Presentamos el caso clínico de un preescolar con antecedente de malformación pulmonar que 43 días tras una neumonectomía izquierda, ingresó al Hospital Padre Hurtado con fiebre de una semana de evolución. En una TAC pulmonar se demostró una gran colección intrapleural izquierda de la que se aisló Streptococcus grupo anginosus y Prevotella spp. Se efectuó tratamiento antimicrobiano con penicilina más clindamicina. Existe gran confusión en la terminología y clasificación de Streptococcus grupo anginosus. En la actualidad no existe duda que es un grupo que posee tres especies, S. anginosus, S. constellatus y S. intermedius. Son parte de la flora normal de orofaringe, nasofaringe, tracto gastrointestinal y vagina. Este grupo ha sido reconocido como causa de infecciones supurativas en niños y adultos. La mayoría de las cepas se describen como susceptibles a penicilina; sin embargo, existen reportes que sugieren la emergencia de resistencia. Se discuten las recomendaciones actuales para el diagnóstico e informe microbiológicosLeft pneumonectomy in a child with congenital pulmonary malformation was performed two months prior to admission. Within one week he had high fever. Chest CT scan showed massive left pleural effusion. Both Streptococcus anginosus group and Prevotella spp. grew from the fluid obtained by pleural punction. Antimicrobial therapy was immediately initiated with clindamycin and penicillin. Streptococus anginosus group is quite confusing in terms of classification and taxonomy. Now it is well recognized that three species belong to this genera: S. anginosus S. constellatus and S. intermedius. They all are considered normal flora of the oropharynx, nasopharynx, gastrointestinal tract and vagina but also they have been identified as agents of suppurative infections in children and adults. Many reports show adequate response to penicillin, however there is some emerging resistance in strains isolated in other studies. In this article we also suggest some diagnostic and microbiologic recommendations

  6. Epidural abscess caused by Streptococcus milleri in a pregnant woman

    OpenAIRE

    Bearman Gonzalo; Lampen Russell

    2005-01-01

    Abstract Background Bacteria in the Streptococcus milleri group (S. anginosus, S. constellatus, and S. intermedius) are associated with bacteremia and abscess formation. While most reports of Streptococcus milleri group (SMG) infection occur in patients with underlying medical conditions, SMG infections during pregnancy have been documented. However, SMG infections in pregnant women are associated with either neonatal or maternal puerperal sepsis. Albeit rare, S. milleri spinal-epidural absce...

  7. Suppression of salivary Streptococcus mutans and lactobacilli by topical caries preventive agents.

    Science.gov (United States)

    Juric, H; Dukic, W; Jankovic, B; Karlovic, Z; Pavelic, B

    2003-12-01

    Reduction of cariogenic bacteria, especially salivary Streptococcus mutans and lactobacilli is a valuable clinical procedure that in many ways alleviates implementation of targeted caries preventive procedures in the entire population. The aim of this study was to investigate the caries preventive values of certain preventive procedures in in vivo conditions. Four groups of subjects, each with 18 children aged from 4-5 and 10-12 years (n = 72) were treated with different caries preventive agent (aminfluoride solution, Proxyt paste, chewing gum containing xylitol and fluoride and chlorhexidine solution). During a period of two months five control measurements for number of salivary Streptococcus mutans (SM) and lactobacilli (LB) were performed. At the end of the study the best result in the reduction of the bacteria was achieved by the application of Proxyt paste and daily use of chewing gum (p xylitol and fluorides on daily basis can be very effective protocol for cariogenic bacteria reduction and in the individual caries prevention. PMID:14768786

  8. Reproduction, distribution and abundance of Bothus constellatus (Pisces: Bothidae, in the Gulf of Tehuantepec, Mexico

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    M. Tapia-García

    2000-03-01

    Full Text Available A total of 3 593 individuals of Bothus constellatus was captured during five oceanographic cruises carried out in the Gulf of Tehuantepec, Mexico. Its distribution, abundance, and reproduction patterns were stated by means of the analysis of the population parameters (i.e. density, biomass, weight and size average, visceral and gonadosomatic index, and maturity stages. B. constellatus is a typical demersal marine species, because it does not occur in estuaries, but occurs near to them on the continental shelf. It is distributed in the Gulf of Tehuantepec in depths lesser than 60 m, with high abundance around the 40 m isobath, and in front of Mar Muerto Lagoon. During January and May the biomass and density were high. The size at first maturity of females is 101 mm total length, and maturation occurs first in zones influenced by estuarine processes. Reproduction and recruitment were detected in all the collections.

  9. Mode of action of a lysostaphin-like bacteriolytic agent produced by Streptococcus zooepidemicus 4881.

    OpenAIRE

    Simmonds, R S; Pearson, L.; Kennedy, R C; Tagg, J.R.

    1996-01-01

    Electron microscopy of zoocin A-treated sensitive streptococcus cells revealed cytoplasmic disruption and ultimately complete rupture of the cell wall. Culture viability and optical density were shown to decrease rapidly and simultaneously in Streptococcus pyogenes FF22 but less quickly in the relatively more resistant Streptococcus mutans 10449. Zoocin A was shown to cleave hexaglycine in a colorimetric cell-free microtiter assay system, and it is concluded that the killing action of zoocin ...

  10. Halistanol sulfate A and rodriguesines A and B are antimicrobial and antibiofilm agents against the cariogenic bacterium Streptococcus mutans

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    Bruna de A. Lima

    2014-12-01

    Full Text Available In the present investigation we report the antibacterial activity of halistanol sulfate A isolated from the sponge Petromica ciocalyptoides, as well as of rodriguesines A and B isolated from the ascidian Didemnum sp., against the caries etiologic agent Streptococcus mutans. The transcription levels of S. mutans virulence genes gtfB, gtfC and gbpB, as well as of housekeeping genes groEL and 16S, were evaluated by sqRT-PCR analysis of S. mutans planktonic cells. There were no alterations in the expression levels of groEL and 16S after antimicrobial treatment with halistanol sulfate A and with rodriguesines A and B, but the expression of the genes gtfB, gtfC and gbpB was down-regulated. Halistanol sulfate A displayed the most potent antimicrobial effect against S. mutans, with inhibition of biofilm formation and reduction of biofilm-associated gene expression in planktonic cells. Halistanol sulfate A also inhibited the initial oral bacteria colonizers, such as Streptococcus sanguinis, but at much higher concentrations. The results obtained indicate that halistanol sulfate A may be considered a potential scaffold for drug development in Streptococcus mutans antibiofilm therapy, the main etiologic agent of human dental caries.

  11. Halistanol sulfate A and rodriguesines A and B are antimicrobial and antibiofilm agents against the cariogenic bacterium Streptococcus mutans

    Scientific Electronic Library Online (English)

    Bruna de A., Lima; Simone P. de, Lira; Miriam H., Kossuga; Reginaldo B., Gonçalves; Roberto G.S., Berlinck; Regianne U., Kamiya.

    2014-12-01

    Full Text Available In the present investigation we report the antibacterial activity of halistanol sulfate A isolated from the sponge Petromica ciocalyptoides, as well as of rodriguesines A and B isolated from the ascidian Didemnum sp., against the caries etiologic agent Streptococcus mutans. The transcription levels [...] of S. mutans virulence genes gtfB, gtfC and gbpB, as well as of housekeeping genes groEL and 16S, were evaluated by sqRT-PCR analysis of S. mutans planktonic cells. There were no alterations in the expression levels of groEL and 16S after antimicrobial treatment with halistanol sulfate A and with rodriguesines A and B, but the expression of the genes gtfB, gtfC and gbpB was down-regulated. Halistanol sulfate A displayed the most potent antimicrobial effect against S. mutans, with inhibition of biofilm formation and reduction of biofilm-associated gene expression in planktonic cells. Halistanol sulfate A also inhibited the initial oral bacteria colonizers, such as Streptococcus sanguinis, but at much higher concentrations. The results obtained indicate that halistanol sulfate A may be considered a potential scaffold for drug development in Streptococcus mutans antibiofilm therapy, the main etiologic agent of human dental caries.

  12. Sialidase activity of the "Streptococcus milleri group" and other viridans group streptococci.

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    Beighton, D.; Whiley, R. A.

    1990-01-01

    Viridans group streptococci were examined for the production of sialidase (neuraminidase) activity, using the fluorescent substrate 4-methylumbelliferyl-alpha-D-N-acetylneuraminic acid in a simple and rapid (15-min) assay. Sialidase was produced by all strains of Streptococcus oralis and S. intermedius and by a majority of S. mitis strains. S. mutans, S. sobrinus, S. gordonii, S. sanguis, S. vestibularis, S. salivarius, S. anginosus, S. constellatus, "S. parasanguis," and the "tufted fibril g...

  13. Streptococcus pneumoniae and Haemophilus influenzae as etiological agents of conjunctivitis outbreaks in the region of Ribeirão Preto, SP, Brazil

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    Marta I. C. MEDEIROS

    1998-01-01

    Full Text Available In the study of conjunctivitis outbreaks occurring from September 1994 to September 1996 in the region of Ribeirão Preto, conjunctival exudates of 92 patients were cultivated in Instituto Adolfo Lutz Laboratory I, Ribeirão Preto. Most cases occurred in the age range 2-7 years. The etiological agents which were most frequently isolated from the analyzed cases were: Streptococcus pneumoniae and Haemophilus influenzae, in 40.22% and 21.74%, respectively. 51.35% of the S. pneumoniae isolated strains were not typable. The oxacillin-resistant S. pneumoniae strains were submitted to the minimum inhibitory concentration test (MIC and three of them presented intermediate resistance, whereas only one was highly resistant to penicillin.No estudo de surtos de conjuntivite ocorridos no período de setembro de 1994 a setembro de 1996, na região de Ribeirão Preto, foram semeadas no Instituto Adolfo Lutz Laboratório I, Ribeirão Preto, exsudatos conjuntivais de 92 pacientes, sendo que a maioria dos casos estava na faixa etária de 2-7 anos. Os agentes etiológicos mais freqüentemente isolados dos casos analisados foram: Streptococcus pneumoniae e Haemophilus influenzae em 40,22% e 21,74% respectivamente. 51,35% das cepas de S. pneumoniae isoladas foram não tipáveis. As cepas de S. pneumoniae oxacilina resistente foram submetidas ao teste de concentração inibitória mínima (CIM, sendo que três apresentaram resistência intermediária e apenas uma foi altamente resistente à penicilina.

  14. Susceptibilidad a antimicrobianos en aislamientos de Streptococcus pneumoniae invasor en Colombia / Susceptibility to antimicrobial agents in isolates of invasive Streptococcus pneumoniae in Colombia

    Scientific Electronic Library Online (English)

    Aura Lucía, Leal; Castañeda, Elizabeth.

    1999-03-01

    Full Text Available Se realizó un estudio para determinar los patrones de susceptibilidad a los antimicrobianos de los aislamientos de Streptococcus pneumoniae causante de enfermedad invasora diagnosticada en Colombia en niños menores de 5 años entre 1994 y 1996 y para establecer la distribución de los tipos capsulares [...] de los aislamientos resistentes. Se analizaron 324 aislamientos recuperados durante la ejecución del Protocolo Nacional de Serotipificación de S. pneumoniae realizado en Santa Fe de Bogotá, Medellín y Cali, Colombia, entre julio de 1994 y marzo de 1996. Se observó que 119 de todos los aislamientos (36,7%) presentaban susceptibilidad disminuida por lo menos a un antimicrobiano, que 39 (12%) presentaban susceptibilidad disminuida a la penicilina y que de estos últimos aislamientos, 29 presentaban resistencia intermedia y 10 resistencia alta. Nueve aislamientos (2,8%) presentaban resistencia a la ceftriaxona, 80 (24,7%) a la combinación de trimetoprima y sulfametoxazol (TMS), 49 (15,1%) al cloranfenicol y 31 (9,6%) a la eritromicina. Se observó resistencia a dos antimicrobianos en 31 aislamientos (9,6%) y multirresistencia en 22 (6,7%). Estos 22 aislamientos mostraron resistencia al TMS. Las asociaciones más frecuentes fueron penicilina, TMS y eritromicina en 5 casos; penicilina, cloranfenicol, TMS y eritromicina en 4; penicilina, ceftriaxona, cloranfenicol y TMS en 3; y penicilina, ceftriaxona, cloranfenicol, TMS y eritromicina en 3 casos. Los serotipos más frecuentes en los aislamientos resistentes a la penicilina fueron: 23F (53,8%), 14 (25,6%), 6B (7,7%), 9V (5,1%), 19F (5,1%) y 34 (2,6%). Los serotipos más frecuentes en los aislamientos resistentes a antimicrobianos distintos de la penicilina fueron: 5 (37,5%), 23F (7,5%), 14 (18,8%) y 6B (13,8%). Esta diferencia en la distribución de los serotipos fue estadísticamente significativa (P Abstract in english A study was done to determine the patterns of susceptibility to antimicrobial agents in isolates of Streptococcus pneumoniae that caused invasive disease diagnosed in children under the age of 5 in Colombia between 1994 and 1996, as well as to establish the distribution of the capsular types of the [...] resistant isolates. The analysis was done using 324 isolates obtained during the performance of the National Serotyping Protocol for S. pneumoniae carried out in Bogotá, Medellín, and Cali, Colombia, between July 1994 and March 1996. Of the 324 isolates, 119 (36.7%) showed diminished susceptibility to at least one antimicrobial agent, including 39 (12%) that showed diminished susceptibility to penicillin. Of these 39 resistant to penicillin, 29 showed intermediate resistance and 10 showed high resistance. Nine isolates (2.8%) showed resistance to ceftriaxone, 80 (24.7%) to the combination of trimethoprim and sulfamethoxazole (TMS), 49 (15.1%) to chloramphenicol, and 31 (9.6%) to erythromycin. Resistance to two antimicrobial agents was observed in 31 isolates (9.6%); multiple resistance was found in 22 (6.7%). These 22 multiresistant isolates all showed resistance to TMS. The most frequent associations were penicillin, TMS, and erythromycin (5 cases); penicillin, chloramphenicol, TMS, and erythromycin (4 cases); penicillin, ceftriaxone, chloramphenicol, and TMS (3 cases); and penicillin, ceftriaxone, chloramphenicol, TMS, and erythromycin (3 cases). The most frequent serotypes in the penicillin-resistant isolates were: 23F (53.8%), 14 (25.6%), 6B (7.7%), 9V (5.1%), 19F (5.1%), and 34 (2.6%). The most frequent serotypes in the isolates resistant to antimicrobial agents other than penicillin were: 5 (37.5%), 23F (7.5%), 14 (18.8%), and 6B (13.8%). This difference in the distribution of the serotypes was statistically significant (P

  15. AG205, a Novel Agent Directed against FabK of Streptococcus pneumoniae

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    Takahata, Sho; Iida, Maiko; Osaki, Yumi; Saito, Jun; Kitagawa, Hideo; Ozawa, Tomohiro; Yoshida, Takuji; Hoshiko, Shigeru

    2006-01-01

    AG205 was identified from high-throughput screening as a potent inhibitor of FabK, the enoyl-ACP reductase in Streptococcus pneumoniae. Specific inhibition of lipid biosynthesis in a macromolecular biosynthesis assay and identification of an Ala141Ser substitution in FabK from spontaneous AG205-resistant mutants indicated that AG205 exerts antibacterial activity against S. pneumoniae through the specific inhibition of FabK.

  16. ?acteriology of pleural infection «Streptococcus milleri group» in the limelight

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    Richard W. Light

    2009-01-01

    Full Text Available SUMMARY. Bacterial infection of the pleura is an old disease that continues to have a considerable mortality, of >15%. It is more common in males, and in the presence of diabetes mellitus, malignancy and alcoholism. The bacteriology of pleural infection has been changing during the past decades. Although pleural fluid culture is the «gold standard» for the identification of microorganisms in the pleural fluid, molecular methods such as polymerase chain reaction (PCR have a notably higher sensitivity (75% versus 60%. Community-acquired pleural infection (CAPI and hospital-acquired pleural infection (HAPI have substantial differences in both their bacteriology and mortality, while the bacteriology of both differs markedly from that of pneumonia. The «Streptococcus milleri group» is the predominant isolate in CAPI, followed by Streptococcus pneumoniae. In HAPI the most common isolates are Staphylococcus aureus, usually methicillin-resistant (MRSA, and Enterococcus spp. Given the higher incidence of CAPI compared to HAPI, «Streptococcus milleri» accounts for the greatest number of pleural infections. The «Streptococcus milleri group» consists of Streptococcus anginosus, Streptococcus constellatus and Streptococcus intermedius. The unique characteristics of these bacteria favour the production of putrifying and necrotizing infections. The most common thoracic infection due to these organisms is empyema. Drainage of the infected pleural fluid and administration of antibiotics are essential components of the management of pleural infection. Knowledge of the pleural infection bacteriology is a useful adjunct in the selection of the appropriate antibiotic treatment. Pneumon 2009; 22(1:46–64.

  17. Emergence in Vietnam of Streptococcus pneumoniae resistant to multiple antimicrobial agents as a result of dissemination of the multiresistant Spain(23F)-1 clone.

    OpenAIRE

    Parry, CM; Duong, NM; Zhou, J.; Mai, NT; Diep, TS; Thinh, LQ; Wain, J.; Van Vinh Chau, N; Griffiths, D; Day, NP; White, NJ; Hien, TT; Spratt, BG; Farrar, JJ

    2002-01-01

    Surveillance for Streptococcus pneumoniae resistant to penicillin and other antimicrobial agents is necessary to define the optimal empirical antibiotic therapy for meningitis in resource-poor countries such as Vietnam. The clinical and microbiological features of 100 patients admitted to the Centre for Tropical Diseases in Ho Chi Minh City, Vietnam, between 1993 and 2002 with invasive pneumococcal disease were studied. A penicillin-nonsusceptible pneumococcus (MIC, > or =0.1 micro g/ml) was ...

  18. Presence and antibiotic susceptibility patterns of contagious mastitis agents (Staphylococcus aureus and Streptococcus agalactiae) isolated from milks of dairy cows with subclinical mastitis

    OpenAIRE

    ?K?Z, Serkan; BA?ARAN, Beren; B?NGÖL, Enver Bar??; ÇET?N, Ömer; KA?IKÇI, Güven; ÖZGÜR, Naciye Yakut; UÇMAK, Melih; Özge YILMAZ; GÜNDÜZ, Mehmet Can; SABUNCU, Ahmet

    2013-01-01

    Mastitis is recognized as one of the most important diseases affecting the dairy industry. The antibiotic susceptibility test is important to achieve accurate treatment in subclinical mastitis. This study was conducted to determine the presence of contagious mastitis agents (Streptococcus agalactiae and Staphylococcus aureus) in 270 bovine milk samples collected from 132 dairy cows with subclinical mastitis in 15 different dairy farms located in the Marmara Region of Turkey. A total of 256 ba...

  19. Susceptibilidad a antimicrobianos en aislamientos de Streptococcus pneumoniae invasor en Colombia Susceptibility to antimicrobial agents in isolates of invasive Streptococcus pneumoniae in Colombia

    OpenAIRE

    Aura Lucía Leal; Castañeda Elizabeth

    1999-01-01

    Se realizó un estudio para determinar los patrones de susceptibilidad a los antimicrobianos de los aislamientos de Streptococcus pneumoniae causante de enfermedad invasora diagnosticada en Colombia en niños menores de 5 años entre 1994 y 1996 y para establecer la distribución de los tipos capsulares de los aislamientos resistentes. Se analizaron 324 aislamientos recuperados durante la ejecución del Protocolo Nacional de Serotipificación de S. pneumoniae realizado en Santa Fe de Bogotá, Medell...

  20. Action of selected agents on the accumulation of /sup 18/F by Streptococcus mutans

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    Yotis, W.W.; Zeb, M.; Brennan, P.C.; Kirchner, F.R.; Glendenin, L.E.; Wu-Yuan, C.D.

    1983-01-01

    The action of certain substances known to induce cellular alterations, or encountered in the oral cavity, on the accumulation of /sup 18/F by Streptococcus mutans GS-5 has been investigated. A 62-67% inhibition in the number of /sup 18/F atoms bound per mg dry weight of cells could be induced by a 15 min pretreatment with 2.7 x 10/sup -4/ M cetyltrimethylammoniumbromide, 1 x 10/sup -1/ M acetic anhydride, or 7 x 10/sup -2/ M HCl. Plate counts indicated that alteration of the cellular composition rather than viability was responsible for this diminution in /sup 18/F accumulation. Prior exposure for 15 min of this organism to 1 M HCHO or 0.1 M NaOH did not alter /sup 18/F accumulation. Of the common salts encountered in the oral cavity, CaCl/sub 2/ enhanced /sup 18/F binding. Pretreatment of the assay cells for 15-160 min with 0.1 mg/ml of trypsin, pronase, protease, ..cap alpha..-glucosidase, dextranase, or lactoferrin had no significant effect on the accumulation of /sup 18/. However, pre-exposure of cells for 60 min to 1-10 mg/ml of either amylase or lipase induced a 40-67% inhibition in the binding of /sup 18/F, while lysozyme enhanced the binding of /sup 18/F by the cells. It would appear then that the binding of /sup 18/F by S. mutans may be altered by certain substances encountered in the oral cavity. 17 references, 1 figure, 5 tables.

  1. In Vitro Activity of Antimicrobial Agents Against Streptococcus Pyogenes Isolates from patients with Acute Tonsillopharyngitis in Dakar, Senegal

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    A. Gueye Ndiaye

    2009-06-01

    Full Text Available Streptococcus pyogenes (S. pyogenes is the most important causative agent of tonsillopharyngitis. Beta-lactam antibiotics, particularly penicillin, are the drug of first choice and macrolides are recommended for patients who are allergic to penicillin. However, other antibiotics are also used for the treatment of streptococcal tonsillopharyngitis. In recent years, the increase in the incidence of respiratory tract pathogens that are resistant to current antibacterial agents highlights the need to monitor the evolution of the resistance of these pathogens to antibiotics. In this study, we assess the susceptibility of 98 isolates of S. pyogenes to 16 antibiotics. The pathogens were recovered from patients with acute tonsillopharyngitis in Dakar, the Senegalese capital city, who were recruited from May 2005 to August 2006. All strains were susceptible to penicillin with low Minimum Inhibitory Concentration (MIC = 0,016 mg/L. Amoxicillin had high activity (100% showing its importance in treatment of streptococcal infections. Cephalosporins had MIC90 values ranging from 0.016 to 0.094 mg/L. Macrolides have shown high activity. All strains were resistant to tetracyclin. Other molecules such as teicoplanin, levofloxacin and chloramphenicol were also active and would represent alternatives to treatment of tonsillopharyngitis due to this pathogen. These results indicate that no significant resistance to antibiotics was found among patients with tonsillopharyngitis studied in Dakar. Limitations of this study were that the number of isolates tested was small and all isolates were collected from one hospital in Dakar. Hence, results may not be representative of the isolates found, in the wider community or other regions of Senegal. Further studies are needed in other parts of Dakar and other geographic regions of Senegal, in order to better clarify the antibiotic susceptibility profile of S. pyogenes isolates recovered from patients with tonsillopharyngitis.

  2. Estudio fitoquímico y actividad antibacterial de Psidium guineense Sw (choba frente a Streptococcus mutans, agente causal de caries dentales Phytochemical study and antibacterial activity of Psidium guíneense Sw (choba against Streptococcus mutans, causal agent of dental caries

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    Adriana María Neira González

    2005-12-01

    Full Text Available Se comprobaron las potencialidades antibacteriales del extracto etanólicoy de sus fracciones éter de petróleo, diclorometano, acetato de etilo y acuosa obtenidos de la cáscara y pulpa de Psidium guineense Sw (choba frente a la bacteria Gram positiva Streptococcus mutans ATCC 31089 y a una cepa de la misma bacteria aislada de paciente. El S. mutans está reconocido como el principal agente causal de las caries dentales. Se comprobó, por técnicas de coloración y cromatografía en capa delgada, el contenido de metabolitos secundarios en los extractos etanólicos crudos y en sus respectivas fracciones. Los ensayos antibacteriales se realizaron por la técnica de perforación en gel empleando la escala de 0,5 de McFarland a 10(8 ufc/mL. Se utilizó agar base sangre y se aplicaron 50 mL de los extractos etanólicos de la cáscara y la pulpa de P. guineense diluidos en DMSO a concentraciones de 400 y 0,4 mg/mL. Según los mayores porcentajes de inhibición obtenidos de estos extractos, se tomaron las fracciones en concentraciones entre 25 y 100 mg/mL y para la cepa S. mutans aislada de paciente, concentraciones de 400 y 200 mg/mL. Los extractos etanólicos crudos mostraron actividad frente a estas bacterias; las fracciones de mayor actividad fueron las nombradas M1FA (fracción acetato de choba fruto cáscara verde seca y M3FA (fracción acetato de choba fruto pulpa verde seca. La actividad antimicrobiana de la especie P. guineense pudiera ser atribuida a los metabolitos secundarios, taninos, flavonoides, terpenos y aldehídos, presentes en el fruto de esta especie.The antibacterial potentialities of the ethanol extract and its petroleum ether, dicloromethane, ethyl acetate, and aqueous fractions obtained from the peel and pulp of Psidium guineense Sw ( choba against the Gram positive Streptococcus mutants ATCC 31089 and a strain of the same germ isolated from a patient, were proved . S. Mutans is recognized as the causal agent of dental caries. The content of secondary metabolites in the crude ethanol extracts and in its respective fractions were proved by staining and thin layer chromatography. The antibacterial tests were made by means of the gel perforation technique and using McFarland's 0.5 scale at 108 ufc/mL. Blood base agar was utilized and 50 mL of the ethanol extracts from the peel and pulp of P. guineense diluted in DMSO at concentrations of 400 and 0.4 mg/mL were applied. According to the highest percentages of inhibition obtained from these extracts, the fractions were taken in concentrations between 25 and 100 mg/ mL and from 400 and 200 mg/mL for the S. mutans strain isolated from a patient. The crude ethanol extracts showed activity against these bacteria. The fractions with the greatest activity were the so-called M1FA (fraction of acetate of choba fruit's dry green peel and M3FA (fraction of acetate of choba fruit's dry green pulp. The antimicrobial activity of the P. guineense species may be attributed to secondary metabolites, taninns, flavonoids, terpenes and aldehydes present in the fruit of this species.

  3. Estudio fitoquímico y actividad antibacterial de Psidium guineense Sw (choba) frente a Streptococcus mutans, agente causal de caries dentales / Phytochemical study and antibacterial activity of Psidium guíneense Sw (choba) against Streptococcus mutans, causal agent of dental caries

    Scientific Electronic Library Online (English)

    Adriana María, Neira González; Martha Beatriz, Ramírez González; Nidia Lizbeth, Sánchez Pinto.

    2005-12-01

    Full Text Available Se comprobaron las potencialidades antibacteriales del extracto etanólicoy de sus fracciones éter de petróleo, diclorometano, acetato de etilo y acuosa obtenidos de la cáscara y pulpa de Psidium guineense Sw (choba) frente a la bacteria Gram positiva Streptococcus mutans ATCC 31089 y a una cepa de l [...] a misma bacteria aislada de paciente. El S. mutans está reconocido como el principal agente causal de las caries dentales. Se comprobó, por técnicas de coloración y cromatografía en capa delgada, el contenido de metabolitos secundarios en los extractos etanólicos crudos y en sus respectivas fracciones. Los ensayos antibacteriales se realizaron por la técnica de perforación en gel empleando la escala de 0,5 de McFarland a 10(8) ufc/mL. Se utilizó agar base sangre y se aplicaron 50 mL de los extractos etanólicos de la cáscara y la pulpa de P. guineense diluidos en DMSO a concentraciones de 400 y 0,4 mg/mL. Según los mayores porcentajes de inhibición obtenidos de estos extractos, se tomaron las fracciones en concentraciones entre 25 y 100 mg/mL y para la cepa S. mutans aislada de paciente, concentraciones de 400 y 200 mg/mL. Los extractos etanólicos crudos mostraron actividad frente a estas bacterias; las fracciones de mayor actividad fueron las nombradas M1FA (fracción acetato de choba fruto cáscara verde seca) y M3FA (fracción acetato de choba fruto pulpa verde seca). La actividad antimicrobiana de la especie P. guineense pudiera ser atribuida a los metabolitos secundarios, taninos, flavonoides, terpenos y aldehídos, presentes en el fruto de esta especie. Abstract in english The antibacterial potentialities of the ethanol extract and its petroleum ether, dicloromethane, ethyl acetate, and aqueous fractions obtained from the peel and pulp of Psidium guineense Sw ( choba) against the Gram positive Streptococcus mutants ATCC 31089 and a strain of the same germ isolated fro [...] m a patient, were proved . S. Mutans is recognized as the causal agent of dental caries. The content of secondary metabolites in the crude ethanol extracts and in its respective fractions were proved by staining and thin layer chromatography. The antibacterial tests were made by means of the gel perforation technique and using McFarland's 0.5 scale at 108 ufc/mL. Blood base agar was utilized and 50 mL of the ethanol extracts from the peel and pulp of P. guineense diluted in DMSO at concentrations of 400 and 0.4 mg/mL were applied. According to the highest percentages of inhibition obtained from these extracts, the fractions were taken in concentrations between 25 and 100 mg/ mL and from 400 and 200 mg/mL for the S. mutans strain isolated from a patient. The crude ethanol extracts showed activity against these bacteria. The fractions with the greatest activity were the so-called M1FA (fraction of acetate of choba fruit's dry green peel) and M3FA (fraction of acetate of choba fruit's dry green pulp). The antimicrobial activity of the P. guineense species may be attributed to secondary metabolites, taninns, flavonoids, terpenes and aldehydes present in the fruit of this species.

  4. Sialidase activity of the "Streptococcus milleri group" and other viridans group streptococci.

    Science.gov (United States)

    Beighton, D; Whiley, R A

    1990-06-01

    Viridans group streptococci were examined for the production of sialidase (neuraminidase) activity, using the fluorescent substrate 4-methylumbelliferyl-alpha-D-N-acetylneuraminic acid in a simple and rapid (15-min) assay. Sialidase was produced by all strains of Streptococcus oralis and S. intermedius and by a majority of S. mitis strains. S. mutans, S. sobrinus, S. gordonii, S. sanguis, S. vestibularis, S. salivarius, S. anginosus, S. constellatus, "S. parasanguis," and the "tufted fibril group" were uniformly negative. Sialidase production may be a useful characteristic to assist in the identification of viridans group streptococci. PMID:2199505

  5. Epidural abscess caused by Streptococcus milleri in a pregnant woman

    Directory of Open Access Journals (Sweden)

    Bearman Gonzalo

    2005-11-01

    Full Text Available Abstract Background Bacteria in the Streptococcus milleri group (S. anginosus, S. constellatus, and S. intermedius are associated with bacteremia and abscess formation. While most reports of Streptococcus milleri group (SMG infection occur in patients with underlying medical conditions, SMG infections during pregnancy have been documented. However, SMG infections in pregnant women are associated with either neonatal or maternal puerperal sepsis. Albeit rare, S. milleri spinal-epidural abscess in pregnancy has been reported, always as a complication of spinal-epidural anesthesia. We report a case of spinal-epidural abscess caused by SMG in a young, pregnant woman without an antecedent history of spinal epidural anesthesia and without any underlying risk factors for invasive streptococcal disease. Case presentation A 25 year old pregnant woman developed neurological symptoms consistent with spinal cord compression at 20 weeks gestation. She underwent emergency laminectomy for decompression and was treated with ceftriaxone 2 gm IV daily for 28 days. She was ambulatory at the time of discharge from the inpatient rehabilitation unit with residual lower extremity weakness. Conclusion To our knowledge, this is the first reported case of a Streptococcus milleri epidural abscess in a healthy, pregnant woman with no history of epidural anesthesia or invasive procedures. This report adds to the body of literature on SMG invasive infections. Treatment of SMG spinal-epidural abscess with neurologic manifestations should include prompt and aggressive surgical decompression coupled with targeted anti-infective therapy.

  6. Caracterización clínica y microbiológica de las infecciones causadas por Streptococcus grupo anginosus / Clinical and microbiological characteristics of infections caused by Streptococcus anginosus group

    Scientific Electronic Library Online (English)

    Gustavo, Caro D.; Ingrid, Riedel K.; Patricia, García C..

    Full Text Available Streptococcus grupo anginosus, y sus especies constellatus, anginosus e intermedius, causan infecciones supuradas. Su identificación microbiológica es compleja pues pueden ser beta-hemolíticos y comparten antígenos de Lancefield con otros estreptococos. Si bien morfológicamente son colonias pequeñas [...] y presentan un olor característicos, si sólo se realiza test de látex para aglutinación del carbohidrato C pueden ser clasificados erróneamente. El objetivo de nuestro trabajo fue evaluar un algoritmo que utiliza 3 pruebas bioquímicas, conocer su susceptibilidad a antimicrobianos y describir las características clínicas de infecciones producidas por Streptococcus grupo anginosus. Se estudiaron cepas de Streptococcus grupo C, G y F, determinando sus características morfológicas de colonia, para identificar cepas de colonia pequeña que se incluyeron en el algoritmo de bajo costo propuesto (b-glucuronidasa y el test Voges-Proskauer) comparándose al método API Rapid ID 32 Strept®, establecido como estándar de oro. Se estudiaron 219 cepas, de las cuales 101 presentaron las características morfológicas compatibles con grupo anginosus, identificándose S. constellatus en 58% (59/101), S. anginosus en 37% (37/101) y S. intermedius en 5% (5/101). Las cepas aisladas procedían principalmente de infecciones piogénicas (61%, 62/101), en especial de foco abdominal. Se observó 98% de susceptibilidad a penicilina y cefotaxima y resistencia a eritromicina y clindamicina en 6,8 y 5%, respectivamente. La edad promedio de los pacientes fue de 30 años (2-85), con distribución similar por sexo y predominio de pacientes hospitalizados. Los resultados expuestos demuestra la efectividad del algoritmo de bajo costo para la detección de S. grupo anginosus. En nuestra experiencia este grupo bacteriano conserva su susceptibilidad a penicilina y cefotaxima, siendo necesario vigilar clindamicina y eritromicina Abstract in english Streptococcus anginosus group and its species constellatus, anginosus and intermedius, produce suppurative infections. Its microbiological identification is complex because it can be beta-hemolytic and shares Lancefield antigens with other Streptococci. This group grows as small colonies and present [...] s a characteristic smell, but if only latex test for carbohydrate C agglutination is used it can be erroneously classified. The aims of this publication were to evaluate an algorithm that includes three biochemical tests, and to describe in vitro susceptibility to antibiotics and clinical characteristics of infections caused by Streptococcus anginosus group. Streptoccoccal strains belonging to groups C, G and F were evaluated, determining its colony characteristics in order to select small colony strains that were included into the proposed low cost algorithm (beta-glucurosidase and Voges Proskauer tests) comparing them with API Rapid ID 32 Strept® method, considered the gold standard. Two hundred nineteen strains were studied, 101 had a morphological profile compatible with the anginosus group, identifying S. constellatus in 58% (59/101), S. anginosus in 37% (37/101) and S. intermedius in 5% (5/101). Strains were isolated mainly from pyogenic infections (61%, 62/101), specially from abdominal origin. High grade of penicillin and cefotaxime susceptibility (98%) and low grade resistance to erithromycin and clindamycin (6,8 and 5% respectively) were observed. Mean patient age was 30 years old (2-85), a similar sex distribution with predominance of inpatients. These results document the usefulness of the proposed low cost algorithm for detection of S. anginosus group. In our experience this bacterial group maintains good susceptibility to penicillin and cefotaxime, and we recommend a continous surveillance of clindamycin and erythromycin susceptibility

  7. Activities of a New Oral Streptogramin, XRP 2868, Compared to Those of Other Agents against Streptococcus pneumoniae and Haemophilus Species

    OpenAIRE

    Pankuch, Glenn A.; Kelly, Linda M.; Lin, Gengrong; Bryskier, Andre; Couturier, Catherine; Jacobs, Michael R.; Appelbaum, Peter C

    2003-01-01

    MIC methodology was used to test the antibacterial activity of XRP 2868, a new oral combination of two semisynthetic streptogramins, RPR 132552A and RPR 202868, compared to activities of other antibacterial agents against pneumococci, Haemophilus influenzae, and Haemophilus parainfluenzae. For 261 pneumococci, XRP 2868 and pristinamycin MICs were similar, irrespective of penicillin G and erythromycin A susceptibilities (MIC at which 50% of isolates were inhibited [MIC50], 0.25 ?g/ml; MIC90, 0...

  8. Susceptibility of Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis to 17 oral antimicrobial agents based on pharmacodynamic parameters: 1998-2001 U S Surveillance Study.

    Science.gov (United States)

    Jacobs, Michael R; Bajaksouzian, Saralee; Windau, Anne; Good, Caryn E; Lin, Gengrong; Pankuch, Glenn A; Appelbaum, Peter C

    2004-06-01

    Pharmacokinetic/pharmacodynamic parameters were used to interpret susceptibility data for the oral agents tested in a clinically meaningful way. Among S pneumoniae isolates, >99% were susceptible to respiratory fluoroquinolones, 91.6% to amoxicillin, 92.1% to amoxicillin/clavulanic acid (95.2% at the extended-release formulation breakpoint), 90.6% to clindamycin, 80.4% to doxycycline, 71.0% to azithromycin, 72.3% to clarithromycin, 71.8% to cefprozil and cefdinir, 72.6% to cefuroxime axetil, 66.3% to cexime, 63.7% to trimethoprim/sulfamethoxazole, and 19.7% to cefaclor. Among H influenzae isolates, 28.6% were b-lactamase positive, but virtually all were susceptible to amoxicillin/clavulanic acid (98.3%, with 99.8% at the extended-release formulation breakpoint), cexime (100%), and uoroquinolones (99.8%), whereas 93.5% were susceptible to cefdinir, 82.8% to cefuroxime axetil, 78.1% to trimethoprim/sulfamethoxazole, 70.2% to amoxicillin, 25.1% to doxycycline, 23.2% to cefprozil, and 5% to cefaclor, azithromycin and clarithromycin. Most isolates of M catarrhalis were resistant to amoxicillin, cefaclor, cefprozil, and trimethoprim/sulfamethoxazole. Thus significant b-lactam and macrolide/azalide resistance in Streptococcus pneumoniae and b-lactamase production and trimethoprim/sulfamethoxazole resistance in untypeable Haemophilus influenzae are still present. The results of this study should therefore be applied to clinical practice based on the clinical presentation of the patient, the probability of the patient's having a bacterial rather than a viral infection, the natural history of the disease, the potential of pathogens to be susceptible to various oral antimicrobial agents, the potential for cross-resistance between agents with S pneumoniae, and the potential for pathogens to develop further resistance. Antibiotics should be used judiciously to maintain remaining activity and chosen carefully based on activity determined by pharmacokinetic/pharmacodynamic-based breakpoints to avoid these bacteria developing further resistance, particularly to fluoroquinolones. PMID:15177851

  9. Single- and Multistep Resistance Selection Studies on the Activity of Retapamulin Compared to Other Agents against Staphylococcus aureus and Streptococcus pyogenes

    OpenAIRE

    Kosowska-Shick, Klaudia; Clark, Catherine; Credito, Kim; McGhee, Pamela; Dewasse, Bonifacio; Bogdanovich, Tatiana; Appelbaum, Peter C

    2006-01-01

    Retapamulin had the lowest rate of spontaneous mutations by single-step passaging and the lowest parent and selected mutant MICs by multistep passaging among all drugs tested for all Staphylococcus aureus strains and three Streptococcus pyogenes strains which yielded resistant clones. Retapamulin has a low potential for resistance selection in S. pyogenes, with a slow and gradual propensity for resistance development in S. aureus.

  10. Prevalencia de serotipos de Streptococcus pneumoniae y otros gérmenes causantes de otitis media aguda en niños de Latinoamérica: Revisión sistemática de la bibliografía / Prevalence of serotypes of Streptococcus pneumoniae and other agents that cause acute otitis media in children in Latin America: A systematic review of the literature

    Scientific Electronic Library Online (English)

    Norma Carolina, Barajas Viracachá.

    2011-06-01

    Full Text Available La otitis media aguda (OMA) es un diagnóstico frecuente en pediatría. Streptococcus pneumoniae continúa siendo el germen más prevalente a nivel mundial, seguido de Haemophilus influenzae. Sin embargo, la introducción de vacunas contra el neumococo ha venido cambiando la microbiología de la OMA. Obje [...] tivo. Establecer la prevalencia del neumococo, sus serotipos y la prevalencia de otros gérmenes comunes en niños latinoamericanos con OMA. Fuente de los datos. Se realizó una búsqueda sistemática de artículos originales en siete bases de datos, limitada a publicaciones entre 1999 y 2010, a menores de 18 años y a idiomas inglés y castellano. Se completó la búsqueda por estrategia de "bola de nieve". Métodos de revisión. Los criterios de elegibilidad incluyeron artículos originales de prevalencia de corte transversal, realizados en población pediátrica latinoamericana y con criterios de inclusión y exclusión homogéneos. Se extrajo la información pertinente de los artículos seleccionados. Resultados. Once artículos cumplieron los criterios de elegibilidad. En Latinoamérica, específcamente en Costa Rica, Chile, Brasil y Argentina, el germen más prevalente fue Streptococcus pneumoniae (43,5%), (el serotipo más frecuente es el 19F, excepto en Argentina, donde es el 14) seguido por Haemophilus influenzae (30%) y Moraxella catarrhalis (6,4%). Conclusiones. El germen más prevalente en OMA en niños latinoamericanos es Streptococcus pneumoniae, hallazgo concordante con lo registrado en Europa y Estados Unidos. Se requieren más estudios en los otros países de la región y su población pediátrica vacunada contra el neumococo, con el fin de establecer un perfil epidemiológico y microbiológico actualizado de Latinoamérica. Abstract in english Acute otitis media (AOM) is a common diagnosis in children. Streptococcus pneumoniae remains the most prevalent agent worldwide, followed by Haemophilus influenzae. However, the introduction of pneumococcal vaccines has changed the microbiology of AOM. Objective. To establish the prevalence of pneum [...] ococcal serotypes and other common germs in Latin American children with AOM. Source of data. We carried out a systematic search for original articles in seven databases, limited to publications between 1999 and 2010, children under 18, and English and Spanish languages. Search was completed with "snowball" strategy. Review methods. Eligibility criteria included original prevalence cross-sectional articles, conducted in pediatric populations in Latin America, with homogeneous inclusion and exclusion criteria. Relevant information was extracted from the selected articles. Results. Eleven articles met the eligibility criteria. In Latin America, specifically Costa Rica, Chile, Brazil and Argentina, Streptococcus pneumoniae (43.5%) was the most frequent germ, (serotype 19F is the most frequent, except in Argentina where it is 14) followed by Haemophilus influenzae (30%) and Moraxella catarrhalis (6.4%). Conclusions. The more prevalent germ in Latin American children AOM is Streptococcus pneumoniae, a finding consistent with those from Europe and the U.S. Further studies are required in the other countries of the region and its pediatric pneumococcal vaccinated population, in order to establish an updated epidemiological and microbiological profile in Latin America.

  11. Mutacins of Streptococcus mutans

    Directory of Open Access Journals (Sweden)

    Regianne Umeko Kamiya

    2011-12-01

    Full Text Available The colonization and accumulation of Streptococcus mutans are influenced by various factors in the oral cavity, such as nutrition and hygiene conditions of the host, salivary components, cleaning power and salivary flow and characteristics related with microbial virulence factors. Among these virulence factors, the ability to synthesize glucan of adhesion, glucan-binding proteins, lactic acid and bacteriocins could modify the infection process and pathogenesis of this species in the dental biofilm. This review will describe the role of mutacins in transmission, colonization, and/or establishment of S. mutans, the major etiological agent of human dental caries. In addition, we will describe the method for detecting the production of these inhibitory substances in vitro (mutacin typing, classification and diversity of mutacins and the regulatory mechanisms related to its synthesis.

  12. Mutacins of Streptococcus mutans

    Scientific Electronic Library Online (English)

    Regianne Umeko, Kamiya; Tiago, Taiete; Reginaldo Bruno, Gonçalves.

    2011-12-01

    Full Text Available The colonization and accumulation of Streptococcus mutans are influenced by various factors in the oral cavity, such as nutrition and hygiene conditions of the host, salivary components, cleaning power and salivary flow and characteristics related with microbial virulence factors. Among these virule [...] nce factors, the ability to synthesize glucan of adhesion, glucan-binding proteins, lactic acid and bacteriocins could modify the infection process and pathogenesis of this species in the dental biofilm. This review will describe the role of mutacins in transmission, colonization, and/or establishment of S. mutans, the major etiological agent of human dental caries. In addition, we will describe the method for detecting the production of these inhibitory substances in vitro (mutacin typing), classification and diversity of mutacins and the regulatory mechanisms related to its synthesis.

  13. Streptococcus mutans y caries dental / Streptococcus mutans and dental caries

    Scientific Electronic Library Online (English)

    Juan Carlos, Ojeda-Garcés; Eliana, Oviedo-García; Luis Andrés, Salas.

    2013-01-01

    Full Text Available Streptococcus mutans es uno de los microorganismos cariogénicos asociados a la caries dental. De acuerdo con la hipótesis de la placa ecológica, la caries dental es la consecuencia de cambios en el balance natural de la microflora de la placa dental causados por la alteración de las condiciones ambi [...] entales locales (homeostasis microbiana oral). El estudio de su participación en la colonización de tejidos dentales, implantación e interacción con otros microrganismos es de mucha importancia para la comprensión de la dinámica de las biopelículas dentales. Por medio de técnicas de biología molecular, se ha avanzado en la identificación de los diferentes tipos que habitan la cavidad oral, los productos que generan y que son críticos para su implantación, las interacciones con otras especies y el desarrollo de nuevos procedimientos que ayuden su identificación como uno de los agentes más importantes en la caries dental. Esta revisión examina los últimos avances en la biología de Streptococcus mutans, su papel en la génesis de la caries y las técnicas de identificación y estudio más usadas en los últimos años. Abstract in english Streptococcus mutans is one of cariogenic microorganisms associated with tooth decay. According with the hypothesis of the ecological plaque, dental caries is the consequence of changes in the natural balance in the dental plaque microflora (oral microbial homeostasis). Its role in the colonization [...] of dental tissues, implantation and interaction with other microorganisms is of paramount importance for the understanding of the dynamics of dental biofilms. By means of molecular biology techniques, there have been advances in the identification of the different types that live in the oral cavity, the products they produce which are critical for its implantation, the interaction with other species and the development of new procedures that help its identification as one of the most important agents in dental caries. This review examines the latest advances in the biology of Streptococcus mutans, its role in the genesis of the caries and the identification and study techniques most used in recent years.

  14. Streptococcus pneumoniae, mecanismos de resistencia antimicrobiana

    Directory of Open Access Journals (Sweden)

    Amauri Noda Albelo

    2011-09-01

    Full Text Available El Streptococcus pneumoniae, principal agente causal de la neumonía comunitaria, líder en la etiología de la otitis media y la meningitis, en las últimas 3 décadas ha incrementado, de manera importante, su resistencia a los agentes terapéuticos más utilizados, como los betalactámicos, macrólidos, azálidos y fluroquinolonas. La versatilidad adaptativa del microorganismo le ha permitido crear mecanismos capaces de sobreponerse a cualquiera de estas agresiones terapéuticas con un grado variable de eficacia. Se realiza una revisión de los mecanismos más importantes implicados en la adquisición de resistencia antimicrobiana por S. pneumoniae, y se precisan algunos de los factores de riesgo implicados en infección por S. pneumoniae resistente.

  15. Antibiotic Resistances of Yogurt Starter Cultures Streptococcus thermophilus and Lactobacillus bulgaricus

    OpenAIRE

    Sozzi, Tommaso; Smiley, Martin B.

    1980-01-01

    Twenty-nine strains of Lactobacillus bulgaricus and 15 strains of Streptococcus thermophilus were tested for resistance to 35 antimicrobial agents by using commercially available sensitivity disks. Approximately 35% of the isolates had uncharacteristic resistance patterns.

  16. Laboratory Growth and Maintenance of Streptococcus pyogenes (The Group A Streptococcus, GAS)

    OpenAIRE

    Gera, Kanika; Kevin S. McIver

    2013-01-01

    Streptococcus pyogenes is a Gram-positive bacterium that strictly infects humans. It is the causative agent of a broad spectrum of diseases accounting for millions of infections and at least 517, 000 deaths each year worldwide (Carapetis et al., 2005). It is a nutritionally fastidious organism that ferments sugars to produce lactic acid and has strict requirements for growth. To aid in the study of this organism, this unit describes the growth and maintenance of S. pyogenes.

  17. Interactions between Oral Bacteria: Inhibition of Streptococcus mutans Bacteriocin Production by Streptococcus gordonii

    OpenAIRE

    Wang, Bing-yan; Kuramitsu, Howard K.

    2005-01-01

    Streptococcus mutans has been recognized as an important etiological agent in human dental caries. Some strains of S. mutans also produce bacteriocins. In this study, we sought to demonstrate that bacteriocin production by S. mutans strains GS5 and BM71 was mediated by quorum sensing, which is dependent on a competence-stimulating peptide (CSP) signaling system encoded by the com genes. We also demonstrated that interactions with some other oral streptococci interfered with S. mutans bacterio...

  18. Comparrisson of MICs of ceftioufur and other antimicrobial agents against bacterial pathogens of swine from the United States, Canada and Denmark

    DEFF Research Database (Denmark)

    Salmon, S.A.; Watts, J.L.; Case, C.A.; Hoffmann, L.J.; Wegener, Henrik Caspar; Yancey, R.J.

    1995-01-01

    The MICs of ceftiofur and other antimicrobial agents, tested for comparison, for 515 bacterial isolates of pigs from the United States, Canada, and Denmark with various diseases were compared. The organisms tested included Actinobacillus pleuropneumoniae, Escherichia coli, Pasteurella multocida, Salmonella choleraesuis, Salmonella typhimurium, Streptococcus suis, Streptococcus dysgalactiae subsp. equisimilis, Streptococcus equi subsp. equi, and Streptococcus equi subsp. zooepidemicus. In additio...

  19. Meningitis por Streptococcus suis / Streptococcus suis meningitis

    Scientific Electronic Library Online (English)

    D. E., Geffner Sclarsky; R., Moreno Muñoz; Mª.S., Campillo Alpera; F.J., Pardo Serrano; A., Gómez Gómez; Mª.D., Martínez-Lozano.

    2001-06-01

    Full Text Available La infección humana por Streptococcus suis (S. suis) es una zoonosis, con un riesgo ocupacional conocido y que suele presentarse como meningitis purulenta, que tiene baja mortalidad y frecuentes secuelas de hipoacusia y ataxia. Se han publicado menos de 150 casos humanos desde el informe original de [...] hace 30 años. Hay una reconocida distribución geográfica viviendo la mayoría de los afectados en el norte de Europa y el sudeste Asiático. En España se han comunicado dos pacientes con enfermedad por S. suis. Presentamos dos pacientes con meningitis por S. suis, que acudieron a nuestro hospital en el plazo de un mes. Ambos eran hombres con exposición laboral a cerdos. Presentaron hipoacusia neurosensorial y ataxia de la marcha. Un paciente tuvo parálisis facial periférica y diplopía por paresia del sexto par contralateral con resolución completa a los tres meses. Lo excepcional de la meningitis por S. suis en nuestro país, no debe hacernos olvidar la importancia de registrar el riesgo laboral en la anamnesis. Abstract in english Human infection by Streptococcus suis (S. suis) is a zoonosis, with a known occupational risk and clinical presentation mainly as a purulent meningitis with low mortality and frequent hearing loss and ataxia sequela. Less than 150 human cases have been reported since original one thirty years ago. T [...] here is a geographical distribution most patients living in northen Europe and south Asia. S. suis disease in human has been reported in two patients in Spain the last years. We present two patients with S. suis meningitis, both were men with occupation related by pork meet, and good outcome. They come at our hospital in a lapse of one month. Both had neurosensorial hearing loss and walking ataxia. One patient had peripheral facial paralysis and diplopia because of paresia of contralateral sixth nerve, with complete resolution at three months.The rare presentation of S. suis meningitis in our country must not forget us to record the working risk at anamnesis.

  20. Streptococcus mutans Murein Hydrolase

    OpenAIRE

    Catt, Diana M.; Gregory, Richard L.

    2005-01-01

    Allelic replacement of the C terminus of a Streptococcus mutans surface protein affects murein hydrolase activity. The targeted open reading frame encodes a 67-kDa protein (SmaA) with an N-terminal signal sequence and cleavage site, three 46-amino-acid (aa) direct repeats, and two 88-aa direct repeats. The identical autolytic profile was obtained using a sortase mutant (SrtA?).

  1. ANTIBIOFILM ACTIVITY OF SALIX ALBA PLANT EXTRACT AGAINST STREPTOCOCCUS MUTANS AND STREPTOCOCCUS AUREUS ISOLATED FROM DENTAL PLAQUE SAMPLES

    OpenAIRE

    Mussrat Fayaz; P.K.SIVAKUMAAR

    2014-01-01

    Most of the pathogens have the ability to form biofilms which makes them resistant to the antimicrobial agents. The emergence of new multi drug resistant strains is a big concern. Hence there is a growing need to find alternative antimicrobial agents. Plants have been used for ancient years to control many diseases. In the present study we evaluated antibiofilm activity of Salix alba bark extract against the Streptococcus mutans and Staphylococcus aureus which are the main...

  2. Genetic Transformation of Streptococcus mutans

    OpenAIRE

    Perry, Dennis; Kuramitsu, Howard K.

    1981-01-01

    Three strains of Streptococcus mutans belonging to serotypes a, c, and f were transformed to streptomycin resistance by deoxyribonucleic acids derived from homologous and heterologous streptomycin-resistant strains of S. mutans and Streptococcus sanguis strain Challis. Homologous transformation of S. mutans was less efficient than heterologous transformation by deoxyribonucleic acids from other strains of S. mutans.

  3. Streptococcus pneumoniae, mecanismos de resistencia antimicrobiana / Streptococcus pneumoniae, mechanisms of antimicrobial resistance

    Scientific Electronic Library Online (English)

    Amauri, Noda Albelo; Lázaro Arturo, Vidal Tallet; Joan Iavier, Vidal Tallet; Leanet, Hernández Álvarez.

    2011-09-01

    Full Text Available El Streptococcus pneumoniae, principal agente causal de la neumonía comunitaria, líder en la etiología de la otitis media y la meningitis, en las últimas 3 décadas ha incrementado, de manera importante, su resistencia a los agentes terapéuticos más utilizados, como los betalactámicos, macrólidos, az [...] álidos y fluroquinolonas. La versatilidad adaptativa del microorganismo le ha permitido crear mecanismos capaces de sobreponerse a cualquiera de estas agresiones terapéuticas con un grado variable de eficacia. Se realiza una revisión de los mecanismos más importantes implicados en la adquisición de resistencia antimicrobiana por S. pneumoniae, y se precisan algunos de los factores de riesgo implicados en infección por S. pneumoniae resistente. Abstract in english The Streptococcus pneumoniae, the main causal agent of community pneumonia, leader in the etiology of the otitis media and the meningitis, during the past three decades has increase in a significant way its resistance to the more used therapeutic agents including the beta-lactamase, macrolides, azal [...] ides and fluroquinolones. Adaptive versatility of the microorganism allows it to create mechanisms able to overcome to any of these therapeutical aggressions with a variable degree of effectiveness. Authors made a review of the more important mechanisms involved in acquisition of the antimicrobial resistance by S. pneumoniae and some of risk factors involved in the infection due to resistant S. pneumoniae are specified.

  4. Sepsis neonatal por Streptococcus Grupo B Group B Streptococcus neonatal sepsis: up-to-date

    Directory of Open Access Journals (Sweden)

    MAGDALENA CRUZ O

    2008-10-01

    Full Text Available El Streptococcus grupo B (SGB es uno de los principales agentes causales de sepsis neonatal precoz, siendo un importante factor de morbimortalidad neonatal y de costos en salud pública. Se han implementado múltiples estrategias para evitar la transmisión vertical desde la madre colonizada a su recién nacido, de modo de prevenir la infección de éste último. La más usada en la actualidad es la profilaxis antibiótica administrada a la madre en el momento del parto dependiendo del resultado de un cultivo perineal realizado entre las semanas 35 y 37 de gestación. Mediante esta estrategia se ha logrado disminuir de manera importante la incidencia de la sepsis neonatal por este agente, pero existen aprehensiones acerca de la posible generación de resistencia antibiótica o reacciones adversas a fármacos por parte de la madre. Por esto último, nuevas técnicas de prevención se encuentran en estudio, como las vacunas contra el SGB. En los recién nacidos la infección por Streptococcus agalactiae puede manifestarse de diversas maneras, siendo la sepsis y la meningitis las más frecuentes y mortales. El porcentaje de secuelas entre los sobrevivientes es elevado, por lo que ante la sospecha precoz de infección debe iniciarse tratamiento antibiótico a la brevedad.Group B Streptococcus is one of the leading bacterias causing early onset neonatal sepsis. It constitutes an important factor of neonatal morbidity and mortality and high costs in health. Many strategies have been formulated to avoid vertical transmission from the colonized mother to the newborn, in an attempt to prevent infection of the infant. The most used nowadays is antibiotic prophylaxis given to the mother during labor, depending on the results of recto-vaginal culture taken during 35 to 37 weeks of gestation. This strategy has importantly diminished the prevalence of early onset neonatal sepsis by this agent, although there is still concern about the potential generation of antibiotic resistance and drug-induced adverse reactions in the mother. New techniques for prevention are being developed, such as vaccines against Streptococcus. In the newborn, infection caused by Streptococcus has a broad spectrum of clinical manifestations, like sepsis and meningitis which are the most frequent and lethal. Neurological sequelae are common among the survivors, so an early suspicion of disease must lead to a prompt antibiotic treatment.

  5. Latest developments on Streptococcus suis: an emerging zoonotic pathogen: part 1.

    OpenAIRE

    M Segura; Zheng, H.; De Greeff, A.; Gao, GF; Grenier, D; Jiang, Y.; Lu, C (Chuang); Maskell, D.; Oishi, K.; Okura, M; Osawa, R.; Schultsz, C; Schwerk, C; Sekizaki, T; Smith, H.

    2014-01-01

    First International Workshop on Streptococcus suis, Beijing, China, 12-13 August 2013 The first international workshop on Streptococcus suis, which is an important swine pathogen and emerging zoonotic agent, took place in Beijing, jointly organized by the Faculty of Veterinary Medicine, University of Montreal, Canada and the National Institute for Communicable Disease Control and Prevention, China CDC. The aim of the meeting was to gather together, for the first time, more than 80 researchers...

  6. Genetic Manipulation of Streptococcus pyogenes (The Group A Streptococcus, GAS)

    OpenAIRE

    Le Breton, Yoann; Kevin S. McIver

    2013-01-01

    Streptococcus pyogenes (the group A streptococcus, GAS) is a Gram-positive bacterium responsible for a wide spectrum of diseases ranging from mild superficial infections (pharyngitis, impetigo) to severe often life-threatening invasive diseases (necrotizing fasciitis, streptococcal toxic shock syndrome) in humans. This unit describes molecular techniques for the genetic manipulation of S. pyogenes with detailed protocols for transformation, gene disruption, allelic exchange, transposon mutage...

  7. Streptococcus mutans Out-competes Streptococcus gordonii in vivo

    OpenAIRE

    Tanzer, J. M.; Thompson, A.; K. Sharma; Vickerman, M.M.; Haase, E M; Scannapieco, F.A.

    2012-01-01

    Streptococcus gordonii and Streptococcus mutans avidly colonize teeth. S. gordonii glucosyltransferase (GtfG) and amylase-binding proteins (AbpA/AbpB), and S. mutans glucosyltransferase (GtfB), affect their respective oral colonization abilities. We investigated their interrelationships and caries association in a rat model of human caries, examining the sequence of colonization and non- vs. high-sucrose diets, the latter being associated with aggressive decay in humans and rats. Virulence-ch...

  8. Characterization of hemin binding activity of Streptococcus pneumoniae.

    OpenAIRE

    Tai, S S; Wang, T R; Lee, C. J.

    1997-01-01

    Streptococcus pneumoniae is a causative agent of bacterial pneumonia, otitis media, meningitis, and bacteremia. It causes considerable morbidity and mortality throughout the world, especially among children, the elderly, and immunocompromised individuals. We have demonstrated previously that the growth of S. pneumoniae is limited under iron-depleted conditions and can be restored by the addition of either hemin or hemoglobin. In the present study, we showed that S. pneumoniae had the ability ...

  9. Group A Streptococcus Endometritis following Medical Abortion

    OpenAIRE

    Gendron, Nicolas; Joubrel, Caroline; Nedellec, Sophie; Campagna, Jennifer; Agostini, Aubert; Doucet-Populaire, Florence; Casetta, Anne; Raymond, Josette; Poyart, Claire; Kernéis, Solen

    2014-01-01

    Medical abortion is not recognized as a high-risk factor for invasive pelvic infection. Here, we report two cases of group A Streptococcus (GAS; Streptococcus pyogenes) endometritis following medical abortions with a protocol of oral mifepristone and misoprostol.

  10. Streptococcus suis vaccines: candidate antigens and progress.

    Science.gov (United States)

    Segura, Mariela

    2015-12-01

    Streptococcus suis is a major swine pathogen and an emerging zoonotic agent of human meningitis and streptococcal toxic shock-like syndrome. S. suis is a well-encapsulated pathogen and multiple serotypes have been described based on the capsular polysaccharide antigenic diversity. In addition, high genotypic, phenotypic and geographic variability exits among strains within the same serotype. Besides, S. suis uses an arsenal of virulence factors to evade the host immune system. Together, these characteristics have challenged the development of efficacious vaccines to fight this important pathogen. In this careful and comprehensive review, clinical field information and experimental data have been compiled and compared for the first time to give a precise overview of the current status of vaccine development against S. suis. The candidate antigens and vaccine formulations under research are examined and the feasibility of reaching the goal of a "universal" cross-protective S. suis vaccine discussed. PMID:26468755

  11. Penicillin-induced lysis of Streptococcus mutans.

    OpenAIRE

    Kral, T A; Callaway, M D

    1984-01-01

    Treatment of Streptococcus mutans GS-5 cells with concentrations of penicillin G within a relatively narrow range resulted in substantial lysis. This penicillin-induced lysis was dependent upon cell density and pH of the lysis medium. Other oral streptococci (Streptococcus sobrinus, Streptococcus rattus, and Streptococcus cricetus) also demonstrated substantial levels of penicillin-induced lysis under appropriate conditions. Lesser degrees of lysis were seen in a related organism, Streptococc...

  12. Purulent Pericarditis Caused by Group A Streptococcus

    OpenAIRE

    Bhaduri-McIntosh, Sumita; Prasad, Meeta; Moltedo, José; Vázquez, Marietta

    2006-01-01

    Purulent pericarditis is a rare disease that is most often caused by organisms such as Staphylococcus aureus, Streptococcus pneumoniae, viridans streptococci, Haemophilus influenzae, and anaerobic bacteria. We present an unusual case of purulent pericarditis caused by Streptococcus pyogenes, Lancefield group A streptococcus (GAS), and we provide a review of the literature.

  13. Native valve endocarditis due to Streptococcus vestibularis and Streptococcus oralis.

    Science.gov (United States)

    Doyuk, Elif; Ormerod, Oliver J; Bowler, Ian C J W

    2002-07-01

    Viridans streptococci are the commonest cause of native valve infective endocarditis (IE). The taxonomy of this group is evolving allowing new disease associations to be made. Streptococcus vestibularis is a recently described member of the viridans group, first isolated from the vestibular mucosa of the human oral cavity. It has rarely been associated with human disease. Streptococcus oralis, another member of the viridans group resident in the human oral cavity is a well known cause of IE and bacteraemia in neutropenic patients. We report the first case of native mitral valve endocarditis due to S. vestibularis in a patient with co-existing S. oralis endocarditis. PMID:12217730

  14. Resultados de la aplicación del protocolo basado en screening para la búsqueda de Streptococcus agalactiae en el tercer trimestre del embarazo: Posible impacto sobre la sepsis neonatal precoz por este agente / PERFORMANCE OF A Streptococcus agalactiae UNIVERSAL SCREENING PROTOCOL DURING THE THIRD THRIMESTER OF PREGNANCY: IMPLICATIONS IN REDUCING NEONATAL GROUP B STREPTOCOCCAL SEPSIS

    Scientific Electronic Library Online (English)

    ANA M., GUZMÁN D.; FERNANDO, ABARZÚA C.; CRISTIAN, BELMAR J.; PATRICIA, GARCÍA C..

    Full Text Available Streptococcus agalactiae (SGB) es la principal causa de sepsis neonatal precoz (SNP). Recientemente el CDC ha planteado tratar sólo pacientes con factores de riesgo o detectar a las portadoras realizando cultivo vaginal-perianal en el 3º trimestre del embarazo (screening universal). En nuestro hospi [...] tal hasta el año 1999 sólo se trataba a las pacientes con factores de riesgo, presentando en el bienio 1997/1998 una tasa de SNP por SGB de 1,84/1.000 nacidos vivos. Entre octubre 1999 y noviembre 2000 se aplicó screening universal encontrándose 20% de portadoras. En el período de estudio hubo dos casos de SNP por SGB: un prematuro y un R.N. de término sin factor de riesgo a cuya madre no se le tomó cultivo. La incidencia del período fue de 0,73/1.000 R.N. vivos, lo que indica una disminución de 61% con respecto al período previo. Abstract in english Group B streptococcal infection is the most important cause of neonatal sepsis. The CDC has proposed two alternative strategies for its control: antibiotic treatment only of pregnant women with risk factors or antibiotic treatment of identified group B streptococcal carriers after culturing all preg [...] nant women. At our institution until 1999 we only treated women with risk factors. The incidence of group B streptococcal sepsis in 1997/1998 was 1.84/1.000 per 1.000 live births. Between October 1999 and November 2000 we established universal screening. Maternal GBS carriage rate was 20%. Two newborn infants acquired group B streptococcal sepsis: one premature newborn and one on term newborn infant of a mother without screening. The successful implementation and manteinance of a screening protocol reduced neonatal group B streptococcal sepsis in a 61% rate with an incidence of 0.73/1.000 live births.

  15. Resultados de la aplicación del protocolo basado en screening para la búsqueda de Streptococcus agalactiae en el tercer trimestre del embarazo: Posible impacto sobre la sepsis neonatal precoz por este agente PERFORMANCE OF A Streptococcus agalactiae UNIVERSAL SCREENING PROTOCOL DURING THE THIRD THRIMESTER OF PREGNANCY: IMPLICATIONS IN REDUCING NEONATAL GROUP B STREPTOCOCCAL SEPSIS

    Directory of Open Access Journals (Sweden)

    ANA M. GUZMÁN D.

    2001-01-01

    Full Text Available Streptococcus agalactiae (SGB es la principal causa de sepsis neonatal precoz (SNP. Recientemente el CDC ha planteado tratar sólo pacientes con factores de riesgo o detectar a las portadoras realizando cultivo vaginal-perianal en el 3º trimestre del embarazo (screening universal. En nuestro hospital hasta el año 1999 sólo se trataba a las pacientes con factores de riesgo, presentando en el bienio 1997/1998 una tasa de SNP por SGB de 1,84/1.000 nacidos vivos. Entre octubre 1999 y noviembre 2000 se aplicó screening universal encontrándose 20% de portadoras. En el período de estudio hubo dos casos de SNP por SGB: un prematuro y un R.N. de término sin factor de riesgo a cuya madre no se le tomó cultivo. La incidencia del período fue de 0,73/1.000 R.N. vivos, lo que indica una disminución de 61% con respecto al período previo.Group B streptococcal infection is the most important cause of neonatal sepsis. The CDC has proposed two alternative strategies for its control: antibiotic treatment only of pregnant women with risk factors or antibiotic treatment of identified group B streptococcal carriers after culturing all pregnant women. At our institution until 1999 we only treated women with risk factors. The incidence of group B streptococcal sepsis in 1997/1998 was 1.84/1.000 per 1.000 live births. Between October 1999 and November 2000 we established universal screening. Maternal GBS carriage rate was 20%. Two newborn infants acquired group B streptococcal sepsis: one premature newborn and one on term newborn infant of a mother without screening. The successful implementation and manteinance of a screening protocol reduced neonatal group B streptococcal sepsis in a 61% rate with an incidence of 0.73/1.000 live births.

  16. Development of primer sets for loop-mediated isothermal amplification that enables rapid and specific detection of Streptococcus dysgalactiae, Streptococcus uberis and Streptococcus agalactiae

    Science.gov (United States)

    Streptococcus dysgalactiae, Streptococcus uberis and Streptococcus agalactiae are the three main pathogens causing bovine mastitis, with great losses to the dairy industry. Rapid and specific loop-mediated isothermal amplification methods (LAMP) for identification and differentiation of these three ...

  17. Detección y caracterización de Streptococcus agalactiae en muestras para urocultivo Detection and characterization of Streptococcus agalactiae in urinary samples for culture

    Directory of Open Access Journals (Sweden)

    José Viegas Caetano

    2004-12-01

    Full Text Available La frecuencia de los aislamientos de Streptococcus agalactiae en el laboratorio clínico es cada vez mayor. Dada su importancia como patógeno, fundamentalmente relacionado a infecciones del tracto urinario, sepsis neonatal y puerperal, se hace necesario mejorar los métodos de detección. El presente trabajo pretende estudiar la frecuencia de los aislamientos de Streptococcus agalactiae en muestras para urocultivo con especial atención en las pacientes embarazadas. Se evaluaron 17.160 aislamientos durante un período de dos años, tanto de pacientes ambulatorios como de internados, aislándose Streptococcus agalactiae en 170 muestras (1%. Con agar sangre de carnero como medio de aislamiento se logró aumentar la sensibilidad en la detección de este microorganismo al considerar la presencia de colonias beta hemolíticas en las muestras de pacientes embarazadas aún en bajas concentraciones. Sobre un total de 4.868 muestras provenientes de embarazadas se obtuvieron 107 aislamientos de Streptococcus agalactiae que corresponden al 2,2%. De esta forma, pudo detectarse un gran número de pacientes portadoras y prevenir efectivamente los riesgos potenciales. Sobre 88 aislamientos se ensayó la sensibilidad a diferentes agentes antimicrobianos, y pudo observarse una sensibilidad conservada a los agentes beta-lactámicos y una buena respuesta a los tratamientos instaurados.The frequency of Streptococcus agalactiae is growing in the clinical laboratory. Improved detection methods are needed due to its importance as urinary tract, neonatal and puerperal pathogen. The aim of the present work was to study the frequency of Streptococcus agalactiae isolations in urinary culture samples focused on pregnant women. 170 isolates (1% Streptococcus agalactiae were obtained from 17,160 samples of ambulatory and hospitalized patients in a two year period. It was possible to increase the sensitivity of the detection of this microorganism by considering the presence of beta hemolytic colonies in low concentrations in samples of pregnant patients on sheep blood agar plates. Out of 4,868 samples of pregnant women, 107 isolates (2.2% of Streptococcus agalactiae were obtained. By this means it was possible to detect a great number of carriers and to effectively prevent potential risks. The susceptibility of 88 isolates to different antimicrobial agents was tested. A preserved susceptibility to beta-lactam agents and also a positive response to the established treatments were observed.

  18. Streptococcus pyogenes meningitis in children: report of two cases and literature review

    Directory of Open Access Journals (Sweden)

    Mariana V. Arnoni

    2007-06-01

    Full Text Available Streptococcus pyogenes meningitis (SPM occurs sporadically, even with the increase of invasive streptococcal disease observed in the past years. We reported two cases of SPM in infants to alert pediatricians for the possibility of this agent as a cause of meningitis in previously healthy children.

  19. Streptococcus pyogenes meningitis in children: report of two cases and literature review

    Scientific Electronic Library Online (English)

    Mariana V., Arnoni; Eitan N., Berezin; Marco A.P., Sáfadi; Flávia J., Almeida; Cláudia R.C., Lopes.

    2007-06-01

    Full Text Available Streptococcus pyogenes meningitis (SPM) occurs sporadically, even with the increase of invasive streptococcal disease observed in the past years. We reported two cases of SPM in infants to alert pediatricians for the possibility of this agent as a cause of meningitis in previously healthy children. [...

  20. Study of the intra- and interlaboratory reproducibility of partial single base C-sequencing of the 16S rRNA gene and its applicability for the identification of members of the genus Streptococcus.

    Science.gov (United States)

    Storms, Virginie; Baele, Margo; Coopman, Renata; Willems, Anne; de Baere, Thierry; Haesebrouck, Freddy; Verschraegen, Gerda; Gillis, Monique; Vaneechoutte, Mario

    2002-04-01

    The use of Single Base C-Sequencing of the first 500 bases of the 16S rRNA-gene (SBCS) combined with capillary electrophoresis was evaluated for the identification of reference strains of 30 different species within the genus Streptococcus. For SBCS, only dd-CTP's are used in the sequencing reactions instead of the four dideoxy bases and the primer is fluorescently labeled. The reproducibility, interlaboratory exchangeability and discriminative power of this method were studied by comparing the patterns obtained in three laboratories under highly standardized conditions. The interlaboratory reproducibility proved to be high, enabling the construction of a common database for the identification of strains belonging to the streptococcal species studied. Most of the examined species generated distinguishable profiles. SBCS did not differentiate between the closely related species S. constellatus and S. intermedius. Also S. thermophilus and S. vestibularis as well as S. mitis and S. pneumoniae showed highly resembling profiles. The previously reported heterogeneity within the species S. equinus was reflected by SBCS. For all other species, strains belonging to the same species generated indistinguishable patterns. In conclusion, Single Base C-sequencing of the first 500 bases of the 16S rRNA-gene could be a useful and widely applicable method for the identification of bacteria at the species level, with the added advantage of being more rapid and easier to automatize than full sequence determination. PMID:12086189

  1. Adhesion of streptococcus rattus and streptococcus mutans to metal surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Branting, C.; Linder, L.E.; Sund, M.-L.; Oden, A.; Wiatr-Adamczak, E.

    1988-01-01

    The adhesion of Streptococcus rattus BHT and Streptococcus mutans IB to metal specimens of amalgam, silver, tin and copper was studied using (6-/sup 3/H) thymidine labeled cells. In the standard assay the metal specimens were suspended by a nylon thread in an adhesion solution containing a chemically defined bacterial growth medium (FMC), sucrose, and radiolabeled bacteria. Maximum amounts of adhering bacteria were obtained after about 100 min of incubation. Saturation of the metal specimens with bacteria was not observed. Both strains also adhered in the absence of sucrose, indicating that glucan formation was not necessary for adhesion. However, in the presence of glucose, adhesion was only 26-45% of that observed in the presence of equimolar sucrose. Sucrose-dependent stimulation of adhesion seemed to be due to increased cell-to-cell adhesion capacity. Isolated radiolabeled water-insoluble and water-soluble polysaccharides produced from sucrose by S. rattus BHT were not adsorbed to the metal surfaces.

  2. Antagonism between penicillin and erythromycin against Streptococcus pneumoniae in vitro and in vivo

    DEFF Research Database (Denmark)

    Johansen, H K; Jensen, T G; Dessau, Ram; Lundgren, B; Frimodt-Moller, N

    2000-01-01

    The combination of beta-lactam antibiotics and macrolides is often recommended for the initial empirical treatment of acute pneumonia in order to obtain activity against the most important pathogens. Theoretically, this combination may be inexpedient, as the bacteriostatic agent may antagonize the effect of the bactericidal agent. In this study, the possible interaction between penicillin and erythromycin was investigated in vitro and in vivo against four clinical isolates of Streptococcus pneum...

  3. Use of a Bacteriophage Lysin, PlyC, as an Enzyme Disinfectant against Streptococcus equi?

    OpenAIRE

    Hoopes, J. Todd; Stark, Caren J.; Kim, Han Ah; Sussman, Daniel J.; Donovan, David M.; Nelson, Daniel C.

    2009-01-01

    Streptococcus equi is the causative agent of the purulent infection equine strangles. This disease is transmitted through shedding of live bacteria from nasal secretions and abscess drainage or by contact with surfaces contaminated by the bacteria. Disinfectants are effective against S. equi, but inactivation by environmental factors, damage to equipment, and toxicity are of great concern. Bacteriophage-encoded lysins (cell wall hydrolases) have been investigated as therapeutic agents due to ...

  4. Antimicrobial susceptibilities and serotypes of invasive Streptococcus pneumoniae strains in Switzerland.

    OpenAIRE

    Wüst, J.; Huf, E; Kayser, F. H.

    1995-01-01

    In 1993 and 1994, 10 microbiological laboratories in Switzerland collected 351 strains of Streptococcus pneumoniae from invasive infections. Susceptibilities to the main representatives of the chemical classes were as follows: penicillin, 93%; chloramphenicol, 92%; erythromycin, 94%; sulfamethoxazole-trimethoprim, 86%; tetracycline, 92%; vancomycin, 100%. Forty-three strains showed resistance to one agent, and 35 strains showed resistance to two or more antimicrobial agents simultaneously; i....

  5. Acute meningitis by Streptococcus suis

    Directory of Open Access Journals (Sweden)

    Maria-Jesus Corrales-Arroyo

    2012-12-01

    Full Text Available Streptococcus suis is a coccus Gram positive, anaerobic optional. Human infection by this microorganism is a zoonoticdisease that usually presents as purulent meningitis. Mortality is low but is common sequelae. A case of meningitis byS. suis secondary to contact with pigs is presented here. A 35-year-old male patient was admitted to the hospital complainingof high fever, malaise, vomiting and headache. A physical examination revealed decreased level of consciousness,with adequate response to painful stimulus and his eyes with deconjugated gaze. S. suis was isolated in bloodculture. He was treated with cefotaxime, vancomycin and acyclovir in the intensive care unit. He experienced progressiveimprovement. He was discharged with severe deafness and a minimally unstable gait as sequellae. J Microbiol Infect Dis2012; 2(4: 160-162Key words: Streptococcus suis, meningitis, deafness.

  6. Hydrolytic enzymes of "Streptococcus milleri".

    OpenAIRE

    Ruoff, K L; Ferraro, M J

    1987-01-01

    Seventy-two isolates classified as "Streptococcus milleri" were examined for the presence of various hydrolytic enzymes. While no protein or lipid-degrading activities were demonstrated, some isolates showed DNase and mucopolysaccharide-degrading activities. Beta-hemolytic isolates were more likely to produce these enzymes than were nonhemolytic strains. Isolates of one "S. milleri" biotype (mannitol fermentation positive) were uniformly devoid of all enzyme activities tested.

  7. Genome evolution in Streptococcus pneumoniae.

    OpenAIRE

    Kelly L. Wyres; Brueggemann, Angela B.

    2012-01-01

    Streptococcus pneumoniae (the pneumococcus) is a bacterial pathogen responsible for >1.6 million annual deaths globally. Pneumococcal penicillin-resistance is conferred by acquisition of ‘altered’ penicillin-binding protein (pbp) genes. The first penicillin-nonsusceptible pneumococci were identified in the late 1960s. Global pneumococcal penicillin-nonsusceptibility rates rapidly increased in the 1980s/90s.Since 2000, protein-conjugate vaccines, targeting 7, 10 or 13 of the ?94 different pneu...

  8. Streptococcus agalactiae mastitis: a review.

    OpenAIRE

    Keefe, G.P.

    1997-01-01

    Streptococcus agalactiae continues to be a major cause of subclinical mastitis in dairy cattle and a source of economic loss for the industry. Veterinarians are often asked to provide information on herd level control and eradication of S. agalactiae mastitis. This review collects and collates relevant publications on the subject. The literature search was conducted in 1993 on the Agricola database. Articles related to S. agalactiae epidemiology, pathogen identification techniques, milk quali...

  9. Streptococcus mutans: Fructose Transport, Xylitol Resistance, and Virulence

    OpenAIRE

    Tanzer, J.M.; Thompson, A.; Wen, Z.T.; Burne, R A

    2006-01-01

    Streptococcus mutans, the primary etiological agent of human dental caries, possesses at least two fructose phosphotransferase systems (PTSs), encoded by fruI and fruCD. fruI is also responsible for xylitol transport. We hypothesized that fructose and xylitol transport systems do not affect virulence. Thus, colonization and cariogenicity of fruI? and fruCD? single and double mutants, their WT (UA159), and xylitol resistance (Xr) of S. mutans were studied in rats fed a high-sucrose diet. A suc...

  10. Infecciones por Streptococcus agalactiae en un servicio de neonatología abierto / Infections due to Streptococcus agalactiae at an open neonatology service

    Scientific Electronic Library Online (English)

    Manuel, Díaz Álvarez; Daniel, Claver Isás; Julián, Pérez Amarillo.

    2008-12-01

    Full Text Available INTRODUCCIÓN. El objetivo del presente estudio fue conocer las características clínicas y epidemiológicas de las infecciones por estreptococo del grupo B en recién nacidos egresados de los hospitales maternos. MÉTODOS. Se realizó un estudio descriptivo, que incluyó a recién nacidos consecutivos con [...] infecciones por Streptococcus agalactiae, ingresados en el Servicio de Neonatología del Hospital Pediátrico Universitario «Juan M. Márquez» entre febrero de 1992 y diciembre del 2007. Se procesaron y analizaron distintas variables clínicas y epidemiológicas, con cálculo de tasas de incidencia y letalidad, así como relación entre variables categóricas. RESULTADOS. Hubo 76 recién nacidos con infección por Streptococcus agalactiae, lo cual constituyó una tasa promedio anual de 1,9 x 100 ingresos. Predominaron las infecciones de inicio tardío y las adquiridas en la comunidad (89,5 % y 93,4 %, respectivamente). La meningitis fue la forma clínica más frecuente, seguida de la bacteriemia aislada. Hubo 56 de 76 recién nacidos con bacteriemia (73,7 %). El Streptococcus agalactiae tuvo elevada sensibilidad ante la penicilina, la eritromicina, la vancomicina, la cefotaxima y el cloranfenicol. Hubo 7 fallecidos (9,2 %) y todos fueron pacientes con infección del sistema nervioso central. CONCLUSIONES. Streptococcus agalactiae es un agente causal de infecciones que afectan al recién nacido, tanto en la comunidad como en el medio hospitalario. Estas infecciones pueden ser letales en algunos pacientes con infección del sistema nervioso central con bacteriemia o sin ella, aún manteniendo un patrón de elevada susceptibilidad a los antibióticos betalactámicos. Abstract in english INTRODUCCIÓN. The objective of the present study was to know the clinical and epidemiological characteristics of the infections caused by group B Streptococcus in newborns discharged from maternal hospitals. METHODS. A descriptive study that included consecutive infants with infections due to Strept [...] ococcus agalactiae admitted in the Neonatology Service of «Juan M. Márquez» University Pediatric Hospital from February 1992 to December 2007 was conducted. Different clinical and epidemiological variables were processed and analyzed, with calculation of incidence and lethality rates and relation among the categoric variables. RESULTS. There were 76 newborns with infection due to Streptococcus agalactiae for an average annual rate of 1.9 x 100 admissions. It was observed a predominance of late onset infections and of those acquired in the community (89.5 % y 93.4 %, respectively). Meningitis was the most common clinical form followed by isolated bacteriemia. 56 of the 76 newborn infants had bacteriemia (73.7 %). Streptococcus agalactiae showed a high sensitivity to penicillin, erythromycine, vancomycin, cefotaxime and cloranphenicol. There were 7 deaths (9.2 %). All of them had infection of the CNS. CONCLUSIONS. Streptococcus agalactiae is an agent that causes infections affecting the newborn infant, both in the community and in the hospital. These infections may be lethal in some patients with infection of the CNS with o without bacteriemia, even when they maintain a pattern of elevated susceptibility to betalactamic antibiotics.

  11. Gene Repertoire Evolution of Streptococcus pyogenes Inferred from Phylogenomic Analysis with Streptococcus canis and Streptococcus dysgalactiae

    OpenAIRE

    Lefébure, Tristan; Richards, Vince P.; Lang, Ping; Pavinski-Bitar, Paulina; Stanhope , Michael J.

    2012-01-01

    Streptococcus pyogenes, is an important human pathogen classified within the pyogenic group of streptococci, exclusively adapted to the human host. Our goal was to employ a comparative evolutionary approach to better understand the genomic events concomitant with S. pyogenes human adaptation. As part of ascertaining these events, we sequenced the genome of one of the potential sister species, the agricultural pathogen S. canis, and combined it in a comparative genomics reconciliation analysis...

  12. Streptococcus salivarius K12 Limits Group B Streptococcus Vaginal Colonization.

    Science.gov (United States)

    Patras, Kathryn A; Wescombe, Philip A; Rösler, Berenice; Hale, John D; Tagg, John R; Doran, Kelly S

    2015-09-01

    Streptococcus agalactiae (group B streptococcus [GBS]) colonizes the rectovaginal tract in 20% to 30% of women and during pregnancy can be transmitted to the newborn, causing severe invasive disease. Current routine screening and antibiotic prophylaxis have fallen short of complete prevention of GBS transmission, and GBS remains a leading cause of neonatal infection. We have investigated the ability of Streptococcus salivarius, a predominant member of the native human oral microbiota, to control GBS colonization. Comparison of the antibacterial activities of multiple S. salivarius strains by use of a deferred-antagonism test showed that S. salivarius strain K12 exhibited the broadest spectrum of activity against GBS. K12 effectively inhibited all GBS strains tested, including disease-implicated isolates from newborns and colonizing isolates from the vaginal tract of pregnant women. Inhibition was dependent on the presence of megaplasmid pSsal-K12, which encodes the bacteriocins salivaricin A and salivaricin B; however, in coculture experiments, GBS growth was impeded by K12 independently of the megaplasmid. We also demonstrated that K12 adheres to and invades human vaginal epithelial cells at levels comparable to GBS. Inhibitory activity of K12 was examined in vivo using a mouse model of GBS vaginal colonization. Mice colonized with GBS were treated vaginally with K12. K12 administration significantly reduced GBS vaginal colonization in comparison to nontreated controls, and this effect was partially dependent on the K12 megaplasmid. Our results suggest that K12 may have potential as a preventative therapy to control GBS vaginal colonization and thereby prevent its transmission to the neonate during pregnancy. PMID:26077762

  13. Susceptibilidad antimicrobiana de Streptococcus pneumoniae colonizante de nasofaringe en niños colombianos con neumonía Antibiotic susceptibility of Streptococcus pneumoniae colonizing the nasopharynx of Colombian children with pneumonia

    OpenAIRE

    Aura Lucía Leal; Elizabeth Castañeda

    1997-01-01

    Streptococcus pneumoniae es uno de los principales agentes causales de infección respiratoria aguda (IRA) en niños y su resistencia a antibióticos se ha incrementado en todo el mundo. En este estudio se determinaron los patrones de susceptibilidad a antimicrobianos de S. pneumoniae colonizante de las vías respiratorias altas en 272 niños hospitalizados por neumonía en dos hospitales de Santafé de Bogotá. Se aisló S. pneumoniae en 114 pacientes (42%). Se observó susceptibilidad disminuida a la...

  14. Antibiotic susceptibility of Streptococcus pneumoniae colonizing the nasopharynx of Colombian children with pneumonia Susceptibilidad antimicrobiana de Streptococcus pneumoniae colonizante de nasofaringe en niños colombianos con neumonía

    OpenAIRE

    Aura Lucía Leal; Elizabeth Castañeda

    1997-01-01

    Streptococcus pneumoniae is one of the principal causal agents of acute respiratory infection (ARI) in children, and its resistance to antibiotics has increased worldwide. This study examined the patterns of susceptibility to antibiotics of S. pneumoniae that had colonized the upper respiratory tract of 272 children hospitalized for pneumonia in two hospitals in Santafé de Bogotá. S. pneumoniae was isolated from 114 patients (42%). Diminished susceptibility to penicillin was noted in 19 isola...

  15. Infective endocarditis due to Streptococcus gallolyticus associated with colonic displasia.

    Science.gov (United States)

    Quintas, Edna; Pantarotto, Marcos; Moniz, João; Pardal, Nuno; Pinheiro, Maria Dolores; Gomes, Maria Helena; Sarmento, António

    2011-01-01

    Streptococcus gallolyticus is a microorganism belonging to the Streptococcus bovis I group isolated in humans, bovines and equines pigeons, among other animals. Streptococcus bovis is a Streptococcus strain found in the rumen, and has been isolated in the milk of animals with mastitis. The authors describe a case of an adult immunocompetent patient with underlying valvular heart disease, with bacteraemia and infective endocarditis by Streptococcus gallolyticus, in whom adenomatous colonic polyps with dysplasia were identified. PMID:22521029

  16. Genetic Transformation of Streptococcus sanguis (Challis) with Cryptic Plasmids from Streptococcus ferus

    OpenAIRE

    Macrina, Francis L.; Wood, Patricia H.; Jones, Kevin R

    1980-01-01

    By using the basic methodology initially published by Kretschmer et al. (J. Bacteriol. 124:225-231, 1975), we have been able to introduce phenotypically cryptic plasmids from Streptococcus ferus (formerly Streptococcus mutans subsp. ferus) into Streptococcus sanguis by genetic transformation. In this system, the entry of the cryptic plasmids is selected indirectly. This is effected with transforming deoxyribonucleic acid mixtures in which the cryptic plasmid deoxyribonucleic acid is present i...

  17. Penetration of Streptococcus sobrinus and Streptococcus sanguinis into dental enamel.

    Science.gov (United States)

    Kneist, Susanne; Nietzsche, Sandor; Küpper, Harald; Raser, Gerhard; Willershausen, Brita; Callaway, Angelika

    2015-10-01

    The aim of this pilot study was to assess the difference in virulence of acidogenic and aciduric oral streptococci in an in vitro caries model using their penetration depths into dental enamel. 30 caries-free extracted molars from 11- to 16-year-olds were cleaned ultrasonically for 1 min with de-ionized water and, after air-drying, embedded in epoxy resin. After 8-h of setting at room temperature, the specimens were ground on the buccal side with SiC-paper 1200 (particle size 13-16 ?m). Enamel was removed in circular areas sized 3 mm in diameter; the mean depth of removed enamel was 230 ± 60 ?m. 15 specimens each were incubated anaerobically under standardized conditions with 24 h-cultures of Streptococcus sanguinis 9S or Streptococcus sobrinus OMZ 176 in Balmelli broth at 37 ± 2 °C; the pH-values of the broths were measured at the beginning and end of each incubation cycle. After 2, 4, 6, 8, and 10 weeks 3 teeth each were fixed in 2.5% glutaraldehyde in cacodylate buffer for 24 h, washed 3× and dehydrated 30-60min by sequential washes through a series of 30-100% graded ethanol. The teeth were cut in half longitudinally; afterward, two slits were made to obtain fracture surfaces in the infected area. After critical-point-drying the fragments were gold-sputtered and viewed in a scanning electron microscope at magnifications of ×20-20,000. After 10 weeks of incubation, penetration of S. sanguinis of 11.13 ± 24.04 ?m below the break edges into the enamel was observed. The invasion of S. sobrinus reached depths of 87.53 ± 76.34 ?m. The difference was statistically significant (paired t test: p = 0.033). The experimental penetration depths emphasize the importance of S. sanguinis versus S. sobrinus in the context of the extended ecological plaque hypothesis. PMID:25805186

  18. Streptococcus mutans in denture stomatitis patients under antifungal therapy / Streptococcus mutans em pacientes com estomatite protética submetidos à terapia antifúngica

    Scientific Electronic Library Online (English)

    Laurylene César de S., Vasconcelos; Fábio Correia, Sampaio; Maria Carméli Correia, Sampaio; Maria do Socorro Vieira, Pereira; Maria Helena Pereira, Peixoto.

    Full Text Available OBJETIVO: Verificar o número de Streptococcus mutans em saliva de pacientes com estomatite protética antes e após a terapia antifúngica. METODOLOGIA: Após exame clínico de 93 pacientes, 47 foram selecionados para exame micológico e desta amostra foram selecionados trinta pacientes: 15 com diagnóstic [...] o positivo e 15 com diagnóstico negativo de candidose foram avaliados para contagem de S. mutans, determinação de fluxo salivar e capacidade tampão. Higiene bucal e da prótese, tempo de confecção, tipo de lesão e dados salivares foram relacionados com características clínicas e laboratoriais de Candida. RESULTADOS: As lesões frequentes foram dos tipos I (43,5%) e II (53,5%). A quantidade de S. mutans foi seis vezes maior em pacientes com candidose e foi associada com baixo fluxo salivar e higiene oral deficiente. Após a terapia, a redução de S. mutans foi verificada particularmente em pacientes com fluxo salivar normal. Os valores variaram de 0,01 a 3,88 UFC/ml x 10(4). CONCLUSÃO: Os dados sugerem que os Streptococcus colaboram com Candida spp na etiopatogenia da estomatite protética. O uso de agentes antimicrobianos orais pode propiciar efeito benéfico para pacientes com estomatite protética submetidos à terapia antifúngica e que apresentam higiene oral deficiente e parâmetros salivares desfavoráveis. Abstract in english PURPOSE: To assess the number of Streptococcus mutans in saliva of patients with denture stomatitis before and after antifungal therapy. METHODS: After examining 93 patients, 47 were selected for fungal test. Then, from this sample, thirty patients were selected: 15 with positive and 15 with negativ [...] e diagnosis for candidiasis that were evaluated for S. mutans counting, salivary flow and buffer capacity evaluation. Oral hygiene and prosthesis hygiene, period using prosthesis, lesion type and salivary data were related with clinical laboratorial characteristics of the patients with Candida. RESULTS: The most frequent lesions were type I (43.5%) and II (53.5%). The amount of S. mutans was six times higher in patients with candidiasis and it was associated with low salivary flow and poor oral hygiene. After therapy, a reduction of S. mutans was verified particularly in patients with normal salivary flow. The values ranged from 0.01 to 3.88 x 10(4) cfu/mL. CONCLUSION: The data suggest that Streptococcus spp collaborates with Candida spp in the etiology and pathogenesis of denture stomatitis. The use of oral antimicrobial agents may provide a beneficial effect for denture stomatitis patients that are under antifungal therapy and that have poor oral hygiene and unfavorable salivary parameters.

  19. Evaluation of the PASCO Strep Plus Broth Microdilution Antimicrobial Susceptibility Panels for Testing Streptococcus pneumoniae and Other Streptococcal Species

    OpenAIRE

    Mohammed, M. Jasmine; Tenover, Fred C.

    2000-01-01

    Antimicrobial resistance continues to increase worldwide among isolates of Streptococcus pneumoniae and other species of streptococci. Increasing rates of penicillin resistance, particularly in viridans group streptococci, and resistance to multiple classes of antimicrobial agents, including ?-lactams, macrolides, and fluoroquinolones, in pneumococci have increased the importance of having accurate antimicrobial susceptibility testing results for guiding therapy. One commercial method of asse...

  20. Preparation against Streptococcus Pneumoniae-Associated Diseases

    International Science & Technology Center (ISTC)

    Design of Laboratory Sample of Complex Preparation Based on Specific Bacteriophages and their Lytic Enzymes for a Prophylaxis and Treatment of Human and Animals Streptococcus Pneumoniae-Assiciated Diseses

  1. Plasmid-mediated transformation of Streptococcus mutans.

    OpenAIRE

    Kuramitsu, H K; Long, C M

    1982-01-01

    Streptococcus mutans GS-5 was transformed to erythromycin resistance with streptococcal plasmid pVA736. Transformation frequencies were higher with plasmids reisolated from transformed GS-5 cells relative to plasmid originally derived from S. sanguis Challis.

  2. Actividad antibacteriana de Pelargonium peltatum (L.) L'Hér. sobre Streptococcus mutans, Streptococcus sanguis y Streptococcus mitis frente a clorhexidina / Antibacterial activity of Pelargonium peltatum (L.) L'Her. against Streptococcus mutans, Streptococcus sanguis and Streptococcus mitis versus chlorhexidine

    Scientific Electronic Library Online (English)

    Juana del Carmen, Guerrero Hurtado; Zoila Mercedes, Ortiz Rubio; Luis Fernando, Peralta Berrospi; Fredy Romel, Pérez Azahuanche.

    2013-06-01

    Full Text Available Introducción: Pelargonium peltatum (L.) L'Hér (geranio hiedra) es ampliamente utilizado en medicina natural para el tratamiento de enfermedades bucales, pero se desconocen aún sus propiedades farmacológicas, actividad antibacteriana y la composición de sus fitoconstituyentes. Objetivo: realizar un e [...] studio comparativo de la actividad antibacteriana in vitro del extracto acuoso obtenido de las hojas de Pelargonium peltatum (L.) L'Hér (geranio hiedra) sobre Streptococcus mutans, Streptococcus sanguis y Streptococcus mitis, frente a la clorhexidina. Métodos: para el ensayo antibacteriano se empleó el método de difusión en agar. Se trabajó con 18 muestras de microorganismos de cada especie mencionada, aisladas de los pacientes de una clínica dental. Posteriormente, se prepararon 6 concentraciones diferentes del extracto acuoso, para comparar la actividad antibacteriana frente al colutorio de clorhexidina. El análisis fitoquímico preliminar se realizó mediante el ensayo a la gota. Los datos obtenidos se sometieron a análisis estadísticos como estimadores de media y dispersión, análisis de varianza unifactorial y prueba de Tukey. Resultados: la más alta actividad antibacteriana se obtuvo en la concentración de 400 mg/mL y la más baja en la de 25 mg/mL del extracto acuoso, sobre las tres especies de Streptococcus, en comparación con la clorhexidina; con efecto similar a la concentración de 200 mg/mL. El ensayo fitoquímico preliminar indicó la presencia de flavonoides, taninos, esteroides, antocianinas y saponinas. Conclusiones: el extracto acuoso de Pelargonium peltatum tiene actividad antibacteriana sobre Streptococcus mutans, Streptococcus mitis y Streptococcus sanguis. Abstract in english Introduction: Pelargonium peltatum (L.) L'Her (ivy geranium) is widely used in natural medicine for the treatment of oral disease, but its pharmacological properties, antibacterial activity and phytoconstituent composition are still unknown. Objective: carry out a comparative study of the in vitro a [...] ntibacterial activity of the aqueous extract obtained from leaves of Pelargonium peltatum (L.) L'Her (ivy geranium) against Streptococcus mutans, Streptococcus sanguis and Streptococcus mitis versus chlorhexidine. Methods: the agar diffusion method was used for the antibacterial assay. A study was conducted of 18 samples of microorganisms from the above-mentioned species, isolated from patients cared for at a dental clinic. Six different concentrations were prepared of the aqueous extract to compare antibacterial activity versus the chlorhexidine gargle. Preliminary phytochemical analysis was conducted by drop assay. The data obtained were subjected to statistical analyses such as mean and dispersion estimators, unifactorial analysis of variance and Tukey's test. Results: the highest antibacterial activity against the three species of Streptococcus was obtained with the 400 mg/ml concentration, and the lowest with the 25 mg/ml concentration of the aqueous extract, in comparison with chlorhexidine, with a similar effect to the 200 mg/ml concentration. The preliminary phytochemical assay revealed the presence of flavonoids, tannins, steroids, anthocyanins and saponins. Conclusions: the aqueous extract of Pelargonium peltatum has antibacterial activity against Streptococcus mutans, Streptococcus mitis and Streptococcus sanguis.

  3. Seeing Streptococcus pneumoniae, a Common Killer Bacteria

    DEFF Research Database (Denmark)

    Kjærgaard, Rikke Schmidt; Andersen, Ebbe Sloth

    2014-01-01

    Look around you. The diversity and complexity of life on earth is overwhelming and data continues to grow. In our desire to understand and explain everything scientifically from molecular evolution to supernovas we depend on visual representations. This paper investigates visual representations of the bacteria Streptococcus pneumoniae by use of ink, watercolours and computer graphics. We propose a novel artistic visual rendering of Streptococcus pneumoniae and ask what the value of these kind of...

  4. Recommended conservation of the names Streptococcus sanguis, Streptococcus rattus, Streptococcus cricetus, and seven other names included in the Approved Lists of Bacterial Names. Request for an opinion

    DEFF Research Database (Denmark)

    Kilian, Mogens

    2001-01-01

    With reference to the first Principle of the International Code of Nomenclature of Bacteria, which emphasizes stability of names, it is proposed that the original names Streptococcus sanguis, Streptococcus rattus, Streptococcus cricetus, Erwinia ananas, Eubacterium tarantellus, Lactobacillus sake, Nitrosococcus oceanus, Pseudomonas betle, Rickettsia canada and Streptomyces rangoon, all included in the Approved Lists of Bacterial Names, be conserved. Request for an Opinion

  5. The effect of mango and neem extract on four organisms causing dental caries: Streptococcus mutans, Streptococcus salivavius, Streptococcus mitis, and Streptococcus sanguis: An in vitro study

    Directory of Open Access Journals (Sweden)

    Prashant G

    2007-01-01

    Full Text Available Background and Objectives: Chewing twigs of the mango or neem tree is a common way of cleaning the teeth in the rural and semi-urban population. These twigs are also believed to possess medicinal properties. The present study was conducted to evaluate the antimicrobial effects of these chewing sticks on the microorganisms Streptococcus mutans , Streptococcus salivarius , Streptococcus mitis , and Streptococcus sanguis which are involved in the development of dental caries. An additional objective was to identify an inexpensive, simple, and effective method of preventing and controlling dental caries. Materials and Methods: The sticks were sun dried, ground into a coarse powder, and weighed into 5 gm, 10 gm, and 50 gm amounts. These were added to 100 ml of deionized distilled water. After soaking for 48 h at 4°C, the water was filtered. The filtrate was inoculated onto blood agar plates containing individual species of microorganisms and incubated at 37°C for 48 h. Results: Mango extract, at 50% concentration, showed maximum zone of inhibition on Streptococcus mitis . Neem extract produced the maximum zone of inhibition on Streptococcus mutans at 50% concentration. Even at 5% concentration neem extract showed some inhibition of growth for all the four species of organisms. Interpretation and Conclusion: A combination of neem and mango chewing sticks may provide the maximum benefit. We recommend the use of both the chewing sticks.

  6. Disseminated Streptococcus equi subsp. zooepidemicus Infection in a Foal and Associated Mastitis in a Mare

    OpenAIRE

    KOCABIYIK, A. Levent; BÜYÜKCANGAZ, Esra; AKKOÇ, Ahmet

    2008-01-01

    A systemic infection with Streptococcus equi subsp. zooepidemicus is described in a 22-day-old female foal for the first time in Turkey. Clinically the foal was in poor condition and had severe pneumonia. Painful swellings of the carpal and tarsal joints were evident. Examination of the dam revealed clinical mastitis. Postmortem histopathological and microbiological examinations of samples from the foal revealed a disseminated infection with S. equi subsp. zooepidemicus. The causative agent w...

  7. Effects of Oxygen on Biofilm Formation and the AtlA Autolysin of Streptococcus mutans?

    OpenAIRE

    Ahn, Sang-Joon; Burne, Robert A

    2007-01-01

    The Streptococcus mutans atlA gene encodes an autolysin required for biofilm maturation and biogenesis of a normal cell surface. We found that the capacity to form biofilms by S. mutans, one of the principal causative agents of dental caries, was dramatically impaired by growth of the organism in an aerated environment and that cells exposed to oxygen displayed marked changes in surface protein profiles. Inactivation of the atlA gene alleviated repression of biofilm formation in the presence ...

  8. Emergence of Fluoroquinolone Resistance among Multiply Resistant Strains of Streptococcus pneumoniae in Hong Kong

    OpenAIRE

    Ho, Pak-Leung; Que, Tak-lun; Tsang, Dominic Ngai-Chong; Ng, Tak-Keung; Chow, Kin-Hung; Seto, Wing-Hon

    1999-01-01

    The MICs of 17 antimicrobial agents for 181 Streptococcus pneumoniae strains were determined by the E-test. Overall, 69.1% were penicillin resistant (MIC > 0.06 ?g/ml). Resistance to ciprofloxacin (MIC > 2 ?g/ml), levofloxacin (MIC > 2 ?g/ml), or trovafloxacin (MIC > 1 ?g/ml) was found in 12.1, 5.5, or 2.2% of the strains, respectively. These high rates of resistance raise concerns for the future.

  9. Quantitative antimicrobial susceptibility testing of Haemophilus influenzae and Streptococcus pneumoniae by using the E-test.

    OpenAIRE

    Jorgensen, J H; Howell, A W; Maher, L. A.

    1991-01-01

    The E-test (PDM Epsilometer; AB Biodisk, Solna, Sweden) is an antimicrobial agent gradient-coated plastic test strip which allows MIC determinations on agar media. The test is performed in a manner similar to the agar disk diffusion procedure. A collection of Haemophilus influenzae and Streptococcus pneumoniae strains possessing various resistance mechanisms was used to evaluate the E-test method. H. influenzae strains were tested with both Haemophilus test medium (HTM) and PDM ASM II chocola...

  10. Real-Time Monitoring of Streptococcus mutans Biofilm Formation Using a Quartz Crystal Microbalance

    OpenAIRE

    Tam, K; Kinsinger, N.; Ayala, P; Qi, F; Shi, W.; Myung, N. V.

    2007-01-01

    The ability of Streptococcus mutans, a well-known etiological agent in dental caries, to attach and form a biofilm is an important key to its virulence. The effects of various environmental factors (i.e. sucrose concentration, flow rate and temperature as well as genetic manipulations) on the capability of S. mutans (UA 140) to attach, form and detach were monitored in situ using quartz crystal microbalance. The biofilm growth rate was much slower than that of planktonic growth. Greater avail...

  11. Complete Genome Sequence of Streptococcus mutans GS-5, a Serotype c Strain

    OpenAIRE

    Biswas, Saswati; Biswas, Indranil

    2012-01-01

    Streptococcus mutans, a principal causative agent of dental caries, is considered to be the most cariogenic among all oral streptococci. Of the four S. mutans serotypes (c, e, f, and k), serotype c strains predominate in the oral cavity. Here, we present the complete genome sequence of S. mutans GS-5, a serotype c strain originally isolated from human carious lesions, which is extensively used as a laboratory strain worldwide.

  12. Regulation of the Glucosyltransferase (gtfBC) Operon by CovR in Streptococcus mutans

    OpenAIRE

    Biswas, Saswati; Biswas, Indranil

    2006-01-01

    Streptococcus mutans is an important etiological agent of dental caries in humans. The extracellular polysaccharides synthesized by cell-associated glucosyltransferases (encoded by gtfBC) from sucrose have been recognized as one of the important virulence factors that promote cell aggregation and adherence to teeth, leading to dental plaque formation. In this study, we have characterized the effect of CovR, a global response regulator, on glucosyltransferase expression. Inactivation of covR i...

  13. Phenotypic characterization of the foldase homologue PrsA in Streptococcus mutans

    OpenAIRE

    Guo, Lihong; Wu, Tingxi; HU, WEI; He, Xuesong; Sharma, Shivani; Webster, Paul; Gimzewski, James K.; Zhou, Xuedong; Lux, Renate; Shi, Wenyuan

    2012-01-01

    Streptococcus mutans is generally considered to be the principal etiological agent for dental caries. Many of the proteins necessary for its colonization of the oral cavity and pathogenesis are exported to the cell surface or the extracellular matrix, a process that requires the assistance of the export machineries. Bioinformatic analysis revealed that the S. mutans genome contains a prsA gene, whose counterparts in other gram positive bacteria, including Bacillus and Lactococcus encode funct...

  14. Susceptibilidad antimicrobiana de Streptococcus pneumoniae colonizante de nasofaringe en niños colombianos con neumonía

    OpenAIRE

    Leal Aura Lucía; Castañeda Elizabeth

    1997-01-01

    Streptococcus pneumoniae es uno de los principales agentes causales de infección respiratoria aguda (IRA) en niños y su resistencia a antibióticos se ha incrementado en todo el mundo. En este estudio se determinaron los patrones de susceptibilidad a antimicrobianos de S. pneumoniae colonizante de las vías respiratorias altas en 272 niños hospitalizados por neumonía en dos hospitales de Santafé de Bogotá. Se aisló S. pneumoniae en 114 pacientes (42%). Se observó susceptibilidad disminuida a la...

  15. Subinhibitory Concentrations of Triclosan Promote Streptococcus mutans Biofilm Formation and Adherence to Oral Epithelial Cells

    OpenAIRE

    Bedran, Telma Blanca Lombardo; Grignon, Louis; Spolidorio, Denise Palomari; Grenier, Daniel

    2014-01-01

    Triclosan is a general membrane-active agent with a broad-spectrum antimicrobial activity that is commonly used in oral care products. In this study, we investigated the effect of sub-minimum inhibitory concentrations (MICs) of triclosan on the capacity of the cariogenic bacterium Streptococcus mutans to form biofilm and adhere to oral epithelial cells. As quantified by crystal violet staining, biofilm formation by two reference strains of S. mutans was dose-dependently promoted, in the range...

  16. In Vitro Development of Resistance to Six Quinolones in Streptococcus pneumoniae, Streptococcus pyogenes, and Staphylococcus aureus

    OpenAIRE

    Boos, Mechthild; Mayer, Susanne; Fischer, Ansgar; Köhrer, Karl; Scheuring, Sibylle; Heisig, Peter; Verhoef, Jan; Fluit, Ad C; Schmitz, F.-J.

    2001-01-01

    Streptococcus pneumoniae, Streptococcus pyogenes, and Staphylococcus aureus isolates were exposed to subinhibitory MICs of ciprofloxacin, sparfloxacin, gatifloxacin, moxifloxacin, clinafloxacin, and gemifloxacin during a 10-day period. Subculturing led to resistance development, regardless of the initial potencies of the quinolones. None of the quinolones was associated with a significantly slower rate of resistance development.

  17. Prevalência de Streptococcus ?-hemolítico em crianças portadoras de necessidades especiais / Prevalence of ?-hemolytic Streptococcus in children with special health care needs

    Scientific Electronic Library Online (English)

    Viviane Martha Santos de, Morais; Alice Ramos, Orsi; Fernanda Cristina de Albuquerque, Maranhão; Therezita Maria Peixoto Patury Galvão, Castro; Karina Cavalcante Beltrão de, Castro; Denise Maria Wanderlei, Silva.

    2012-10-01

    Full Text Available Faringotonsilite causada por Streptococcus ?-hemolítico afeta principalmente crianças e imunocomprometidos, sendo Streptococcus pyogenes (Grupo A) o agente mais comum em faringotonsilites bacterianas. OBJETIVO: Este trabalho objetivou a busca por Streptococcus ?-hemolítico do Grupo A (SBHGA) e Não A [...] (SBHGNA) na orofaringe de indivíduos com necessidades especiais da APAE (Maceió-AL). MÉTODO:Estudo prospectivo com amostras da orofaringe de pacientes com síndrome de Down e outras desordens mentais (teste) e estudantes de escola privada (controle) de 5-15 anos. Culturas em ágar sangue (5%) foram identificadas através dos testes de Gram/catalase e o método de disco difusão com bacitracina/sulfametoxazol-trimetoprim, aplicando-se o teste Chi-quadrado em análises estatísticas. RESULTADOS: Um total de 222 colônias bacterianas foram isoladas em 74 indivíduos da APAE e 65 no grupo controle. No grupo teste, episódios prévios de faringotonsilites foram relatados por 36,49% (27/74) e 9,46% (7/74) foram diagnosticados com sintomas e/ou sinais sugestivos de infecção orofaríngea. Nenhuma amostra de S. pyogenes foi confirmada na APAE, sendo todas identificadas como SBHGNA, com cinco SBHGA no grupo controle. CONCLUSÃO:A identificação precoce de Streptococcus ?-hemolítico é importante para o tratamento rápido de faringotonsilites e a ausência de S. pyogenes evita futuras sequelas supurativas ou não supurativas no grupo da APAE. Abstract in english Pharyngotonsillitis by ?-hemolytic Streptococcus mostly affects children and imunocompromissed, being Streptococcuspyogenes (Group A) the most common agent in bacterial pharyngotonsillitis. AIM:This work targeted the research of ?-hemolytic Streptococcus Group-A (SBHGA) and No-A (SBHGNA) in the orop [...] harynx of individuals with special health needs from the APAE (Maceió-AL). METHOD: A prospective study with oropharynx samples from patients with Down syndrome and other mental disorders (test) and students from a private school (control) aged 5-15 years. Cultures in blood agar (5%) were identified through Gram/catalase tests and bacitracin/trimethoprim-sulfamethoxazole disk diffusion method, applying the chi-squared statistical analysis. RESULTS: A total of 222 bacterial colonies were isolated in 74 individuals from APAE and 65 in the control group. In the test group, previous episodes of pharyngotonsillitis were reported by 36.49% (27/74) and 9.46% (7/74) were diagnosed with symptoms and/or signs suggestive of oropharynx infection. No positive sample of S. pyogenes was confirmed at APAE, being all samples classified as SBHGNA, with 5 SBHGA in the control group. CONCLUSION: The early identification of ?-hemolytic Steptococcus is important for the fast treatment of pharyngotonsillitis and the absence of S. pyogenes avoid future suppurative or not-suppurative sequels in the group from APAE.

  18. Streptococcus mutans in denture stomatitis patients under antifungal therapy =Streptococcus mutans em pacientes com estomatite protética submetidos à terapia antifúngica

    Directory of Open Access Journals (Sweden)

    Vasconcelos, Laurylene César de S. et al.

    2010-01-01

    Full Text Available Objetivo: Verificar o número de Streptococcus mutans em saliva de pacientes com estomatite protética antes e após a terapia antifúngica. Metodologia: Após exame clínico de 93 pacientes, 47 foram selecionados para exame micológico e desta amostra foram selecionados trinta pacientes: 15 com diagnóstico positivo e 15 com diagnóstico negativo de candidose foram avaliados para contagem de S. mutans, determinação de fluxo salivar e capacidade tampão. Higiene bucal e da prótese, tempo de confecção, tipo de lesão e dados salivares foram relacionados com características clínicas e laboratoriais de Candida. Resultados: As lesões frequentes foram dos tipos I (43,5% e II (53,5%. A quantidade de S. mutans foi seis vezes maior em pacientes com candidose e foi associada com baixo fluxo salivar e higiene oral deficiente. Após a terapia, a redução de S. mutans foi verificada particularmente em pacientes com fluxo salivar normal. Os valores variaram de 0,01 a 3,88 UFC/ml x 104. Conclusão: Os dados sugerem que os Streptococcus colaboram com Candida spp na etiopatogenia da estomatite protética. O uso de agentes antimicrobianos orais pode propiciar efeito benéfico para pacientes com estomatite protética submetidos à terapia antifúngica e que apresentam higiene oral deficiente e parâmetros salivares desfavoráveis.

  19. Chemical Agents

    Science.gov (United States)

    ... Agents Incapacitating Agents Metals Nerve Agents Pulmonary Agents Riot Control Agents Toxic Alcohols Vesicants Chemical-Specific Fact ... Barium Benzene Brevetoxin Bromine (CA) Bromobenzylcyanide (CA) see Riot Control Agents BZ C Carbon Monoxide Chlorine (CL) ...

  20. Parotiditis por Streptococcus Pyogenes: Presentacion de un caso

    Directory of Open Access Journals (Sweden)

    Zoila del S. López-Díaz

    1995-08-01

    Full Text Available La glándula parótida es generalmente afectada por procesos inflamatorios. Su etiología se debe a infecciones primarias de la glándula o como complicación de infecciones sistémicas. Se reporta el Stafilococcus aureus como el agente causal más frecuente de parotiditis aguda supurada, y se señalan además otras bacterias y virus. Se presenta un niño de 9 años de edad con un proceso supurativo agudo de la parótida izquierda de un mes de evolución, con salida de abundante pus por el conducto de Stenon. Se realizó cultivo de la secreción e identificación de Streptococcus B hemolítico grupo A, a pesar de haber recibido antibioticoterapia previa. Se utilizó ampicillina y se tuvo en cuenta la sensibilidad in vitro; no presentó mejoría clínica, por lo que se decidió el empleo de la sialografía como alternativa terapéutica en este caso. Se obtuvo la resolución del proceso supurativo infeccioso y además se evidenció en este estudio la pérdida del estroma parotídeo.

  1. Geno- and Phenotypic Diversity of Avian Isolates of Streptococcus gallolyticus subsp. gallolyticus (Streptococcus bovis) and Associated Diagnostic Problems?

    OpenAIRE

    Chadfield, M. S.; Christensen, J P; Decostere, A.; Christensen, H.; Bisgaard, M.

    2006-01-01

    Recently, strains of Streptococcus bovis were reclassified as Streptococcus gallolyticus. In the present study we describe for the first time an outbreak of S. gallolyticus in a broiler flock. Mortality during the first week was normal (

  2. Spontaneous retroperitoneal abscess caused by streptococcus pyogenes

    Directory of Open Access Journals (Sweden)

    C. Petrogiannopoulos

    2007-03-01

    Full Text Available The retroperitoneum is a potential space that can be infected by several microbes. We describe the case of a 38- year-old woman who was presented to us with abdominal pain and fever for 6 days. Laboratory studies showed leukocytosis (WBC=18000 and an ubnormal liver function tests (AST=91U/l, ALT=122U/l, ALP=277U/l. A computed tomography of the abdomen revealed a retroperitoneal abscess, while the abdominal viscera were normal. Culture of the pus, obtained during surgical drainage, showed Streptococcus pyogenes. Although streptococcal infections are very usual in clinical practice, streptococcus pyogenes has been reported as a very rare cause of spontaneous retroperitoneal abscess, especially for immunocompetent patients. The patient was treated first with intravenous antibiotics with no response, and then with surgical drainage, with fully recovery. Key words: Streptococcus pyogenes, abscess, retroperitoneum

  3. Inhibitory activity by barley coffee components towards Streptococcus mutans biofilm.

    Science.gov (United States)

    Stauder, Monica; Papetti, Adele; Daglia, Maria; Vezzulli, Luigi; Gazzani, Gabriella; Varaldo, Pietro E; Pruzzo, Carla

    2010-11-01

    It was shown that barley coffee (BC) interferes with Streptococcus mutans adsorption to hydroxyapatite. After BC component fractionation by dialysis and gel filtration chromatography (GFC), it was found that the low molecular mass ( 1,000 kDa) melanoidin fraction display strong anti-adhesive properties towards S. mutans. In this study, we have further examined the potential of BC, BC LMM fraction and BC HMM melanoidin fraction as caries controlling agents by evaluating their anti-biofilm activity.The effects of BC and BC fractions on biofilm formation by S. mutans ATCC 25175 and its detachment from pre-developed biofilms were evaluated by microtiter plate assay. It was found that BC and its fractions, at concentrations ranging from 60 to 15 mg ml(-1) that are devoid of antimicrobial activity, inhibited S. mutans biofilm formation. An increase of S. mutans ATCC 25175 detachment from 24 h developed biofilm was observed at the highest tested concentrations. Interestingly, BC and BC fractions also showed anti-biofilm activity towards a variety of S. mutans clinical strains isolated from saliva, plaque and caries lesions of adult donors. In general, the HMM melanoidin fraction was more active than the LMM fraction. These findings, classifying BC LMM fraction and BC HMM melanoidin fractions as natural anti-biofilm agents, represent the basis for studying their possible use as anti-caries agents. PMID:20361189

  4. Streptococcus pneumoniae NanC

    Science.gov (United States)

    Owen, C. David; Lukacik, Petra; Potter, Jane A.; Sleator, Olivia; Taylor, Garry L.; Walsh, Martin A.

    2015-01-01

    Streptococcus pneumoniae is an important human pathogen that causes a range of disease states. Sialidases are important bacterial virulence factors. There are three pneumococcal sialidases: NanA, NanB, and NanC. NanC is an unusual sialidase in that its primary reaction product is 2-deoxy-2,3-didehydro-N-acetylneuraminic acid (Neu5Ac2en, also known as DANA), a nonspecific hydrolytic sialidase inhibitor. The production of Neu5Ac2en from ?2–3-linked sialosides by the catalytic domain is confirmed within a crystal structure. A covalent complex with 3-fluoro-?-N-acetylneuraminic acid is also presented, suggesting a common mechanism with other sialidases up to the final step of product formation. A conformation change in an active site hydrophobic loop on ligand binding constricts the entrance to the active site. In addition, the distance between the catalytic acid/base (Asp-315) and the ligand anomeric carbon is unusually short. These features facilitate a novel sialidase reaction in which the final step of product formation is direct abstraction of the C3 proton by the active site aspartic acid, forming Neu5Ac2en. NanC also possesses a carbohydrate-binding module, which is shown to bind ?2–3- and ?2–6-linked sialosides, as well as N-acetylneuraminic acid, which is captured in the crystal structure following hydration of Neu5Ac2en by NanC. Overall, the pneumococcal sialidases show remarkable mechanistic diversity while maintaining a common structural scaffold. PMID:26370075

  5. Recovery of Streptococcus iniae from Diseased Fish Previously Vaccinated with a Streptococcus Vaccine

    OpenAIRE

    Bachrach, Gilad; Zlotkin, Amir; Hurvitz, Avshalom; Evans, Donald L.; Eldar, Avi

    2001-01-01

    Streptococcus iniae was recovered from diseased rainbow trout (Oncorhynchus mykiss, Walbaum) previously vaccinated against streptococcosis. PCR and serological methods indicate the presence of a new serotype in the diseased fish.

  6. Antibacterial activity of the three essential oils on Streptococcus mutans- an in-vitro study

    Directory of Open Access Journals (Sweden)

    reevidhya. T. M

    2014-12-01

    Full Text Available The aim of the present study was to evaluate the anti bacterial activity of three essential oils Thyme, Peppermint and neem oil on Streptococcus mutans, the potent initiator and leading cause of dental caries world wide. Essential oils are distillates of the volatile compounds of a plant’s secondary metabolism and may act as phytoprotective agents. Their curative effect has been known since antiquity. It is based on a variety of pharmacological properties which are specific for each plant species. Antibacterial activity of the three essential oils, Thyme, Peppermint and neem oil were screened against Streptococcus mutans, using disc diffusion technique. The results of this study showed that the extracts at different concentrations exhibited anti bacterial activity against the bacterial species tested.

  7. Atividade in vitro do extrato de própolis contra agentes bacterianos da mastite bovina In vitro activity of propolis extract against bovine mastitis bacterial agents

    Directory of Open Access Journals (Sweden)

    Andrea Pinto Loguercio

    2006-02-01

    Full Text Available Este trabalho foi desenvolvido com o objetivo de avaliar a atividade in vitro do extrato alcoólico de própolis, contra agentes da mastite bovina, comparando-o aos principais antimicrobianos utilizados no tratamento convencional. Foram utilizados 36 isolados coagulase-positivos de Staphylococcus sp. e 27 isolados de Streptococcus sp.; 94,4% dos Staphylococcus sp. e 85,2% dos Streptococcus sp. foram susceptíveis ao extrato de própolis.The present study aimed to determine the in vitro activity of propolis extract, comparing it to the most common antibacterial drugs against bovine mastitis bacterial agents. Thirty-six isolates of coagulase-positive Staphylococcus sp. and twenty-seven of Streptococcus sp. were analyzed. Coagulase-positive Staphylococcus (94.4% and Streptococcus sp. (85.2% showed susceptibility to propolis extract.

  8. Regulation of ATP-dependent P-(Ser)-HPr formation in Streptococcus mutans and Streptococcus salivarius.

    OpenAIRE

    Thevenot, T; Brochu, D; Vadeboncoeur, C; Hamilton, I. R.

    1995-01-01

    Sugar transport via the phosphoenolpyruvate (PEP) phosphotransferase system involves PEP-dependent phosphorylation of the general phosphotransferase system protein, HPr, at histidine 15. However, gram-positive bacteria can also carry out ATP-dependent phosphorylation of HPr at serine 46 by means of (Ser)HPr kinase. In this study, we demonstrate that (Ser)HPr kinase in crude preparations of Streptococcus mutans Ingbritt and Streptococcus salivarius ATCC 25975 is membrane associated, with pH op...

  9. Adherence of Streptococcus mutans and Streptococcus sanguis to salivary components bound to glass.

    OpenAIRE

    Stinson, M. W.; Jinks, D C; Merrick, J M

    1981-01-01

    Adherence of radiolabeled Streptococcus mutans and Streptococcus sanguis to saliva-treated glass surfaces was studied under conditions which minimized bacteria-glass interactions. Treatment of glass with an alkylsilane solution decreased nonspecific bacterial adherence and enhanced adsorption of radiolabeled salivary components to these surfaces. Addition of Triton X-100 to the bacterial suspensions also reduced nonspecific adherence to siliconized glass, but did not affect adherence to saliv...

  10. Upper limb compartment syndrome secondary to streptococcus pyogenes (Group A streptococcus) infection

    OpenAIRE

    Taylor, J.; Wojcik, A.

    2011-01-01

    Compartment syndrome caused by Streptococcus pyogenes (Group A streptococcus) has rarely been described. We report a case of a healthy 44-year-old male who presented with compartment syndrome of the right forearm and subsequent acute respiratory distress syndrome. The patient received antibiotics and urgent surgical decompression, followed by delayed wound closure without the need for skin grafting. The patient recovered with no loss of power, sensation or range of movement. High index of sus...

  11. Functional Variation of the Antigen I/II Surface Protein in Streptococcus mutans and Streptococcus intermedius

    OpenAIRE

    Petersen, F.C.; Assev, S.; Mei, H.C. van der; Busscher, H J; Scheie, A. A.

    2002-01-01

    Although Streptococcus intermedius and Streptococcus mutans are regarded as members of the commensal microflora of the body, S. intermedius is often associated with deep-seated purulent infections, whereas S. mutans is frequently associated with dental caries. In this study, we investigated the roles of the S. mutans and S. intermedius antigen I/II proteins in adhesion and modulation of cell surface characteristics. By using isogenic mutants, we show that the antigen I/II in S. mutans, but no...

  12. Population diversity and dynamics of Streptococcus mitis, Streptococcus oralis, and Streptococcus infantis in the upper respiratory tracts of adults, determined by a nonculture strategy

    DEFF Research Database (Denmark)

    Bek-Thomsen, Malene; Tettelin, H; Hance, I; Nelson, KE; Kilian, Mogens

    2008-01-01

    We reinvestigated the clonal diversity and dynamics of Streptococcus mitis and two other abundant members of the commensal microbiota of the upper respiratory tract, Streptococcus oralis and Streptococcus infantis, to obtain information about the origin of frequently emerging clones in this habitat. A culture-independent method was used, based on cloning and sequencing of PCR amplicons of the housekeeping gene gdh, which shows remarkable, yet species-specific, genetic polymorphism. Samples were ...

  13. Streptococcus loxodontisalivarius sp. nov. and Streptococcus saliviloxodontae sp. nov., isolated from oral cavities of elephants.

    Science.gov (United States)

    Saito, Masanori; Shinozaki-Kuwahara, Noriko; Hirasawa, Masatomo; Takada, Kazuko

    2014-09-01

    Four Gram-stain-positive, catalase-negative, coccoid-shaped organisms were isolated from elephant oral cavities. The isolates were tentatively identified as streptococcal species based on the results of biochemical tests. Comparative 16S rRNA gene sequencing studies confirmed the organisms to be members of the genus Streptococcus. Two isolates (NUM 6304(T) and NUM 6312) were related most closely to Streptococcus salivarius with 96.8?% and 93.1?% similarity based on the 16S rRNA gene and the RNA polymerase ? subunit encoding gene (rpoB), respectively, and to Streptococcus vestibularis with 83.7?% similarity based on the 60 kDa heat-shock protein gene (groEL). The other two isolates (NUM 6306(T) and NUM 6318) were related most closely to S. vestibularis with 97.0?% and 82.9?% similarity based on the 16S rRNA and groEL genes, respectively, and to S. salivarius with 93.5?% similarity based on the rpoB gene. Based on phylogenetic and phenotypic evidence, these isolates are suggested to represent novel species of the genus Streptococcus, for which the names Streptococcus loxodontisalivarius sp. nov. (type strain NUM 6304(T)?=?JCM 19287(T)?=?DSM 27382(T)) and Streptococcus saliviloxodontae sp. nov. (type strain NUM 6306(T)?=?JCM 19288(T)?=?DSM 27513(T)) are proposed. PMID:24994777

  14. Endocarditis caused by nonhemolytic group B streptococcus.

    OpenAIRE

    Miranda, C.; Gámez, M I; Navarro, J. M.; Rosa-Fraile, M.

    1997-01-01

    We report a case of bacterial endocarditis caused by nonhemolytic group B streptococcus (GBS) in a 67-year-old man with no predisposing risk factors. Nonhemolytic GBS strains rarely cause illness and are usually detected in perinatal infections. We believe this to be the first reported case of endocarditis caused by a nonhemolytic strain of GBS.

  15. Streptococcus pluranimalium: A novel human pathogen?

    OpenAIRE

    Aryasinghe, Lasanthi; Sabbar, Saweera; Kazim, Yasmin; Awan, Liaqat Mahmood; Khan, Hammad Khan Nadir

    2014-01-01

    •Subdural empyema is difficult to differentiate from meningitis on clinical examination alone.•CT or MRI imaging must be performed for definitive diagnosis.•Prompt diagnosis, IV antibiotics and neurosurgical evacuation improve morbidity and mortality.•Use of prophylactic anticonvulsants and wide-exposure craniotomy are recommended.•Streptococcus pluranimalium needs to be further studied to assess for zoonotic potential.

  16. Recurrent Sepsis Caused by Streptococcus pyogenes?

    OpenAIRE

    Rasmussen, Magnus

    2011-01-01

    I report that a 75-year-old man with severe atherosclerosis experienced two episodes of bacteremia with Streptococcus pyogenes of type emm87. Recurrent sepsis with S. pyogenes is extremely rare, and a foot ulcer was the suspected point of entry. The patient did not develop opsonizing antibodies to the isolate.

  17. Prostatic abscess caused by Streptococcus mutans

    OpenAIRE

    Nguyen, Chau; Dascal, Andre; Mendelson, Jack

    1990-01-01

    The first reported case of prostatic abscess caused by Streptococcus mutans isolated in pure culture is described. Urethral dilation for obstruction was unsuccessful, so suprapubic cystostomy was performed. Perineal aspiration under ultrasonic guidance resulted in 10 mL of pus containing pure Strep mutans. Diagnosis of prostatic abscess is difficult since the clinical manifestations are nonspecific.

  18. Regulation of neuraminidase expression in Streptococcus pneumoniae

    Directory of Open Access Journals (Sweden)

    Gualdi Luciana

    2012-09-01

    Full Text Available Abstract Background Sialic acid (N-acetylneuraminic acid; NeuNAc is one of the most important carbohydrates for Streptococcus pneumoniae due of its role as a carbon and energy source, receptor for adhesion and invasion and molecular signal for promotion of biofilm formation, nasopharyngeal carriage and invasion of the lung. Results In this work, NeuNAc and its metabolic derivative N-acetyl mannosamine (ManNAc were used to analyze regulatory mechanisms of the neuraminidase locus expression. Genomic and metabolic comparison to Streptococcus mitis, Streptococcus oralis, Streptococcus gordonii and Streptococcus sanguinis elucidates the metabolic association of the two amino sugars to different parts of the locus coding for the two main pneumococcal neuraminidases and confirms the substrate specificity of the respective ABC transporters. Quantitative gene expression analysis shows repression of the locus by glucose and induction of all predicted transcriptional units by ManNAc and NeuNAc, each inducing with higher efficiency the operon encoding for the transporter with higher specificity for the respective amino sugar. Cytofluorimetric analysis demonstrated enhanced surface exposure of NanA on pneumococci grown in NeuNAc and ManNAc and an activity assay allowed to quantify approximately twelve times as much neuraminidase activity on induced cells as opposed to glucose grown cells. Conclusions The present data increase the understanding of metabolic regulation of the nanAB locus and indicate that experiments aimed at the elucidation of the relevance of neuraminidases in pneumococcal virulence should possibly not be carried out on bacteria grown in glucose containing media.

  19. The prevalence of fluoroquinolone resistance among clinically significant respiratory tract isolates of Streptococcus pneumoniae in the United States and Canada--1997 results from the SENTRY Antimicrobial Surveillance Program.

    OpenAIRE

    Doern, GV; Pfaller, MA; Erwin, ME; Brueggemann, AB; Jones, RN

    1998-01-01

    As part of the SENTRY antimicrobial resistance surveillance program, a total of 1100 clinically significant respiratory tract isolates of Streptococcus pneumoniae were tested for susceptibility to six fluoroquinolone antimicrobial agents: ciprofloxacin, levofloxacin, gatifloxacin, grepafloxacin, sparfloxacin, and trovafloxacin. Isolates were obtained during the 5-month period, February to June, 1997 from 27 United States medical center laboratories and seven laboratories in Canadian health ca...

  20. Phenotypic and genotypic heterogeneity among Streptococcus iniae isolates recovered from cultured and wild fish in North America, Central America and the Caribbean Islands

    Science.gov (United States)

    Streptococcus iniae, the etiological agent of streptococcosis in fish, is an important pathogen of cultured and wild fish worldwide. During the last decade outbreaks of streptococcosis have occurred in a wide range of cultured and wild fish in the Americas and Caribbean islands. To gain a better und...

  1. Endocarditis infecciosa por Streptococcus bovis asociada a instrumentación gastrointestinal / Infective endocarditis caused by Streptococcus bovis

    Scientific Electronic Library Online (English)

    Rafael, Pila Pérez; Victor Adolfo, Holguín Prieto; Ever, Cetina Lozada; Rafael, Pila Peláez; Leandro, Segura Pujal.

    2012-12-01

    Full Text Available La endocarditis por Streptococcus bovis representa el 10% de los casos de endocarditis bacteriana, siendo frecuente su asociación con enfermedades intestinales y hepáticas. Se presenta el caso de una mujer de 36 años con antecedentes de fiebre reumática en la niñez, quien hace un año comenzó con sin [...] tomatología digestiva, para la cual fue sometida a estudios clínicos invasivos como endoscopia y colonoscopia, desarrollando posteriormente una endocarditis con aislamiento microbiológico de Streptococcus bovis. Se detalla la fisiopatología, clínica, diagnóstico y los aspectos terapéuticos de esta entidad. Además se discuten las posibles relaciones de las enfermedades intestinales, las instrumentaciones del tubo digestivo y las hepatopatías con la bacteriemia por Streptococcus bovis biotipo I. Esta asociación sugiere un posible mecanismo de adherencia biotipo-específica que aún no ha sido fehacientemente demostrado. Por último se resalta la conveniencia de someter a exploración digestiva y ecocardiografía a todo paciente con hemocultivos positivos a este tipo de germen. (MÉD.UIS. 2012;25(3):251-8). Abstract in english Endocarditis caused by Streptococcus bovis represents 10% of the cases of bacterial endocarditis and is frequently associated with intestinal and liver diseases. We present the case of a 36-year old female patient with a history of rheumatic fever in childhood. The gastrointestinal symptomatology be [...] gan one year before the bacterial endocarditis. Several invasive clinical investigations as endoscopy and colonoscopy, were performed and subsequently she developed endocarditis. Streptococcus bovis was isolated in microbiological studies. Pathophysiology, clinical manifestations, diagnosis, and treatment are detailed. The association between bacteremia from Streptococcus bovis biotype I and intestinal diseases, instrumentation of the digestive tract, and hepatopathy is reviewed. This association suggests a possible mechanism of bacteremia and endocarditis associated with biotype I but this has not been definitely confirmed. We have highlighted the importance of performing echocardiography in all patients with blood cultures positive for Streptococcus bovis who have had invasive studies of the gastrointestinal tract.(MÉD.UIS. 2012;25(3)251-8).

  2. Frequency of Spontaneous Resistance to Peptide Deformylase Inhibitor GSK1322322 in Haemophilus influenzae, Staphylococcus aureus, Streptococcus pyogenes, and Streptococcus pneumoniae.

    Science.gov (United States)

    Min, Sharon; Ingraham, Karen; Huang, Jianzhong; McCloskey, Lynn; Rilling, Sarah; Windau, Anne; Pizzollo, Jason; Butler, Deborah; Aubart, Kelly; Miller, Linda A; Zalacain, Magdalena; Holmes, David J; O'Dwyer, Karen

    2015-08-01

    The continuous emergence of multidrug-resistant pathogenic bacteria is compromising the successful treatment of serious microbial infections. GSK1322322, a novel peptide deformylase (PDF) inhibitor, shows good in vitro antibacterial activity and has demonstrated safety and efficacy in human proof-of-concept clinical studies. In vitro studies were performed to determine the frequency of resistance (FoR) to this antimicrobial agent in major pathogens that cause respiratory tract and skin infections. Resistance to GSK1322322 occurred at high frequency through loss-of-function mutations in the formyl-methionyl transferase (FMT) protein in Staphylococcus aureus (4/4 strains) and Streptococcus pyogenes (4/4 strains) and via missense mutations in Streptococcus pneumoniae (6/21 strains), but the mutations were associated with severe in vitro and/or in vivo fitness costs. The overall FoR to GSK1322322 was very low in Haemophilus influenzae, with only one PDF mutant being identified in one of four strains. No target-based mutants were identified from S. pyogenes, and only one or no PDF mutants were isolated in three of the four S. aureus strains studied. In S. pneumoniae, PDF mutants were isolated from only six of 21 strains tested; an additional 10 strains did not yield colonies on GSK1322322-containing plates. Most of the PDF mutants characterized from those three organisms (35/37 mutants) carried mutations in residues at or in close proximity to one of three highly conserved motifs that are part of the active site of the PDF protein, with 30 of the 35 mutations occurring at position V71 (using the S. pneumoniae numbering system). PMID:26014938

  3. Real-time PCR for detection of Streptococcus suis serotype 2 in cerebrospinal fluid of human patients with meningitis.

    Science.gov (United States)

    Nga, Tran Vu Thieu; Nghia, Ho Dang Trung; Tu, Le Thi Phuong; Diep, To Song; Mai, Nguyen Thi Hoang; Chau, Tran Thi Hong; Sinh, Dinh Xuan; Phu, Nguyen Hoan; Nga, Tran Thi Thu; Chau, Nguyen Van Vinh; Campbell, James; Hoa, Ngo Thi; Chinh, Nguyen Tran; Hien, Tran Tinh; Farrar, Jeremy; Schultsz, Constance

    2011-08-01

    Streptococcus suis serotype 2 is an emerging zoonotic pathogen and is the main cause of acute bacterial meningitis in adult patients in Vietnam. We developed an internally controlled real-time PCR for detection of S. suis serotype 2 in cerebrospinal fluid (CSF) samples targeted at the cps2J gene. Sensitivity and specificity in culture-confirmed clinical samples were 100%. The PCR detected S. suis serotype 2 infection in 101 of 238 (42.4%) prospectively collected CSF samples, of which 55 (23%) were culture positive. Culture-negative but PCR-positive CSF samples were significantly associated with the use of antimicrobial agents before admission. S. suis serotype 2 infection was more common than infections with Streptococcus pneumoniae and Neisseria meningitidis combined. Our results strikingly illustrate the additional diagnostic value of PCR in patients who are pretreated with antimicrobial agents and demonstrate the extremely high prevalence of S. suis infections among Vietnamese adult patients with bacterial meningitis. PMID:21767702

  4. Infecciones por Streptococcus anginosusen otorrinolaringología: Revisión de 9 casos clínicos / Infections caused by Streptococcus anginosusin otolaryngology: Review of 9 clinical cases

    Scientific Electronic Library Online (English)

    Felipe, Cardemil M; Daniel, Muñoz S; Maritza, Rahal E; Jaime, Osorio M; René, Sepúlveda S; Rodrigo, Urzúa B.

    2013-04-01

    Full Text Available Introducción: El Streptococcus anginosus (SA) es un habitante común de la cavidad oral y tracto gastrointestinal, y puede ser un patógeno agresivo causante de abscesos en varios sitios del cuerpo. Aparentemente, su rol en infecciones de cabeza y cuello está adquiriendo cierta notoriedad y no está cl [...] aramente reportado en la literatura. Objetivo: El objetivo del presente estudio fue evaluar las implicancias clínicas de estas infecciones en otorrinolaringología. Material y método: Estudio retrospectivo de todos los pacientes diagnosticados microbiológicamente con infecciones causadas por Streptococcus anginosus, tratados en el Servicio de Otorrinolaringología del Hospital Barros Luco-Trudeau entre los años 2007 a 2012. Se describen las características clínicas, microbiológicas y el manejo de los pacientes. Resultados: La muestra estuvo constituida por 9 casos, 3 hombres y 6 mujeres, con una mediana de edad de 52 años (rango 6-70). Los sitios de infección fueron: absceso periamigdalino (2 casos), un absceso peritraqueostoma, un absceso submandibular, un absceso submentoniano, un absceso parafaríngeo con extensión retrofaríngea y mediastino, un caso de absceso cerebral frontal secundario a sinusitis frontal complicada, un caso de otitis media crónica activa, y un caso de sinusitis maxilar crónica. Discusión: El SA ha sido reportado como un agente causal de infecciones potencialmente graves en cabeza y cuello. Su identificación requiere de consideraciones especiales para el cultivo, y al ser un microorganismo común puede ser confundido e informado como S viridans o Streptococcus anaeróbico. Es importante reconocer al SA como un patógeno a considerar en infecciones de cabeza y cuello. Abstract in english Introduction: Streptococcus anginosus (SA) is a common inhabitant of the oral cavity and gastrointestinal tract, and can be an aggressive pathogen causing abscesses in various body sites. Apparently, its role in head and neck infections is gaining some notoriety that it is not clearly reported in th [...] e literature. Aim: The aim of this study was to evaluate the clinical implications of this infections in otolaryngology. Material and method: A retrospective case series study of all patients diagnosed microbiologically with Streptococcus anginosus infections treated at the Department of Otolaryngology, HospitalBarros Luco-Trudeau from 2007 to 2012. We describe the clinical and microbiological features, and treatment of each patient. Results: The sample consisted of 9 patients, 3 men and 6 women, with a median age of 52 years (range 6-70). The sites of infection were: peritonsillar abscess (2 cases), peritracheostomy abscess, submandibular abscess, submental abscess, parapharyngeal abscess with retropharyngeal and mediastinal extension, a case of frontal brain abscess secondary to frontal sinusitis, a case of otitis chronic active half, and one case of chronic maxillary sinusitis. Discussion: SA has been reported as a causative agent ofpotentially serious infections in the head and neck region. Their identification requires special considerations for growing, and because of being a common microorganism may be confused and informed as Streptococcus viridans or anaerobic streptococcus. It is important to recognize SA as a relevant pathogen in head and neck infections.

  5. A galactose-specific sugar:phosphotransferase permease is prevalent in the non-core genome of Streptococcus mutans

    OpenAIRE

    Zeng, Lin; Xue, Peng; Stanhope , Michael J.; Burne, Robert A

    2013-01-01

    Three genes predicted to encode the A, B and C domains of a sugar:phosphotransferase system (PTS) permease specific for galactose (EIIGal) were identified in the genomes of 35 of 57 recently-sequenced isolates of Streptococcus mutans, the primary etiological agent of human dental caries. Mutants defective in the EIIGal complex were constructed in 6 of the isolates and showed markedly reduced growth rates on galactose-based medium relative to the parental strains. An EIIGal-deficient strain co...

  6. Complete genome sequence of Streptococcus agalactiae strain SA20-06, a fish pathogen associated to meningoencephalitis outbreaks

    OpenAIRE

    Pereira, Ulisses de Pádua; Rodrigues dos Santos, Anderson; Hassan, Syed Shah; Aburjaile, Flávia Figueira; Soares, Siomar de Castro; Ramos, Rommel Thiago Jucá; Carneiro, Adriana Ribeiro; Guimarães, Luís Carlos; Silva de Almeida, Sintia; Diniz, Carlos Augusto Almeida; Barbosa, Maria Silvanira; Gomes Sá, Pablo; Ali, Amjad; Bakhtiar, Syeda Marriam; Dorella, Fernanda Alves

    2013-01-01

    Streptococcus agalactiae (Lancefield group B; GBS) is the causative agent of meningoencephalitis in fish, mastitis in cows, and neonatal sepsis in humans. Meningoencephalitis is a major health problem for tilapia farming and is responsible for high economic losses worldwide. Despite its importance, the genomic characteristics and the main molecular mechanisms involved in virulence of S. agalactiae isolated from fish are still poorly understood. Here, we present the genomic features of the 1,8...

  7. Comparative Bactericidal Activities of Ciprofloxacin, Clinafloxacin, Grepafloxacin, Levofloxacin, Moxifloxacin, and Trovafloxacin against Streptococcus pneumoniae in a Dynamic In Vitro Model

    OpenAIRE

    Klepser, Michael E; Ernst, Erika J.; Petzold, C. Rosemarie; Rhomberg, Paul; Doern, Gary V.

    2001-01-01

    Several new quinolones that exhibit enhanced in vitro activity against Streptococcus pneumoniae have been developed. Using a dynamic in vitro model, we generated time-kill data for ciprofloxacin, clinafloxacin, grepafloxacin, levofloxacin, moxifloxacin, and trovafloxacin against three isolates of quinolone-susceptible S. pneumoniae. Three pharmacokinetic profiles were simulated for each of the study agents (0.1, 1, and 10 times the area under the concentration-time curve [AUC]). Target 24-h A...

  8. Transcriptional Repressor Rex Is Involved in Regulation of Oxidative Stress Response and Biofilm Formation by Streptococcus mutans

    OpenAIRE

    Bitoun, Jacob P.; Nguyen, Anne H.; Fan, Yuwei; Burne, Robert A; Wen, Zezhang T.

    2011-01-01

    The transcriptional repressor Rex has been implicated in regulation of energy metabolism and fermentative growth in response to redox potential. Streptococcus mutans, the primary causative agent of human dental caries, possesses a gene that encodes a protein with high similarity to members of the Rex family of proteins. In this study, we showed that Rex-deficiency compromised the ability of S. mutans to cope with oxidative stress and to form biofilms. The Rex-deficient mutant also accumulated...

  9. In Vitro Antimicrobial Effects of Various Combinations of Penicillin and Clindamycin against Four Strains of Streptococcus pyogenes

    OpenAIRE

    Stevens, Dennis L.; Madaras-Kelly, Karl J.; Richards, David M

    1998-01-01

    Previous studies using mouse models of Streptococcus pyogenes necrotizing fasciitis demonstrated that clindamycin had greater efficacy than penicillin. Frequently both agents are used concurrently in the treatment of severe S. pyogenes infections. This study investigated interactions between penicillin and clindamycin. E-test and broth microdilution assays suggested additivity or indifference, while timed-killing assays demonstrated concentration-dependent variable effects. Timed-kill studies...

  10. Seeing Streptococcus pneumoniae, a Common Killer Bacteria

    DEFF Research Database (Denmark)

    Kjærgaard, Rikke Schmidt; Andersen, Ebbe Sloth

    2014-01-01

    Look around you. The diversity and complexity of life on earth is overwhelming and data continues to grow. In our desire to understand and explain everything scientifically from molecular evolution to supernovas we depend on visual representations. This paper investigates visual representations of the bacteria Streptococcus pneumoniae by use of ink, watercolours and computer graphics. We propose a novel artistic visual rendering of Streptococcus pneumoniae and ask what the value of these kind of representations are compared to traditional scientific data. We ask if drawings and computer-assisted representations can add to our scientific knowledge about this dangerous bacteria. Is there still a role for the scientific illustrator in the scientific process and synthesis of scientific knowledge?

  11. Group B Streptococcus Induces Trophoblast Death

    OpenAIRE

    Kaplan, Amber; Chung, Kathy; Kocak, Hande; Bertolotto, Cristina; Uh, Andy; Hobel, Calvin J.; Simmons, Charles F; Doran, Kelly; Liu, George; Equils, Ozlem

    2008-01-01

    Group B streptococcus (GBS) is one of the leading causes of neonatal infection; however the molecular mechanisms involved are not clearly known. Here we used high and low hemolytic GBS isolates and mutant GBS that lacks ?-hemolysin expression and showed that GBS infection or exposure to GBS-hemolysin extract induces primary human trophoblast, placental fibroblast and JEG3 trophoblast cell line death, and that GBS-induced trophoblast death was ?-hemolysin dependent. The fibroblasts and trophob...

  12. Primary psoas abscess due to Streptococcus milleri

    Directory of Open Access Journals (Sweden)

    Abeysekara Abeywardana MS

    2008-02-01

    Full Text Available Abstract Primary Psoas abscess (PPA is an infrequent clinical entity with obscure pathogenesis and vague clinical presentation. High index of clinical suspicion is required for the diagnosis of psoas abscess. We also emphasises the importance of bacteriological confirmation of microorganism involved, although Staphylococcus aureus remains the commonest pathogen. We report an extremely rare case of PPA caused by Streptococcus milleri. Only one case has been reported in literature so far.

  13. Genetic regulation of fructosyltransferase in Streptococcus mutans.

    OpenAIRE

    Kiska, D L; Macrina, F L

    1994-01-01

    Streptococcus mutans possesses several extracellular sucrose-metabolizing enzymes which have been implicated as important virulence factors in dental caries. This study was initiated to investigate the genetic regulation of one of these enzymes, the extracellular fructosyltransferase (Ftf). Fusions were constructed with the region upstream of the S. mutans GS5 Ftf gene (ftf) and a promoterless chloramphenicol acetyltransferase (CAT) gene. The fusions were integrated at a remote site in the ch...

  14. Erythromycin resistance in Streptococcus pyogenes in Italy.

    OpenAIRE

    Bassetti, M; Manno, G.; Collidà, A.; Ferrando, A.; Gatti, G; Ugolotti, E.; Cruciani, M; Bassetti, D

    2000-01-01

    In a prospective study of acute pharyngitis in Italian children, 69 (38.3%) of 180 isolates of Streptococcus pyogenes were resistant to macrolides. S. pyogenes was eradicated in 12 (63.1%) of 19 patients with erythromycin-resistant S. pyogenes treated with clarithromycin and in 22 (88%) of 25 patients with erythromycin-susceptible strains. The constitutive-resistant phenotype was correlated with failure of macrolide treatment.

  15. Streptococcus mutans, Caries and Simulation Models

    OpenAIRE

    Arthur C. Ouwehand; Marika Björklund; Forssten, Sofia D.

    2010-01-01

    Dental caries and dental plaque are among the most common diseases worldwide, and are caused by a mixture of microorganisms and food debris. Specific types of acid-producing bacteria, especially Streptococcus mutans, colonize the dental surface and cause damage to the hard tooth structure in the presence of fermentable carbohydrates e.g., sucrose and fructose. This paper reviews the link between S. mutans and caries, as well as different simulation models that are available for studying carie...

  16. Functional amyloid formation by Streptococcus mutans

    OpenAIRE

    Oli, M. W.; Otoo, H. N.; Crowley, P. J.; Heim, K. P.; M.M. Nascimento; Ramsook, C. B.; Lipke, P. N.; Brady, L. J.

    2012-01-01

    Dental caries is a common infectious disease associated with acidogenic and aciduric bacteria, including Streptococcus mutans. Organisms that cause cavities form recalcitrant biofilms, generate acids from dietary sugars and tolerate acid end products. It has recently been recognized that micro-organisms can produce functional amyloids that are integral to biofilm development. We now show that the S. mutans cell-surface-localized adhesin P1 (antigen I/II, PAc) is an amyloid-forming protein. Th...

  17. Phenotypic Characterization of Streptococcus pneumoniae Biofilm Development

    OpenAIRE

    Allegrucci, Magee; Hu, F.Z.; Shen, K.; Hayes, J.; Ehrlich, Garth D; Post, J. Christopher; Sauer, Karin

    2006-01-01

    Streptococcus pneumoniae is among the most common pathogens associated with chronic otitis media with effusion, which has been hypothesized to be a biofilm disease. S. pneumoniae has been shown to form biofilms, however, little is known about the developmental process, the architecture, and the changes that occur upon biofilm development. In the current study we made use of a continuous-culture biofilm system to characterize biofilm development of 14 different S. pneumoniae strains representi...

  18. Animal Models of Streptococcus pneumoniae Disease

    OpenAIRE

    Chiavolini, Damiana; Pozzi, Gianni; Ricci, Susanna

    2008-01-01

    Summary: Streptococcus pneumoniae is a colonizer of human nasopharynx, but it is also an important pathogen responsible for high morbidity, high mortality, numerous disabilities, and high health costs throughout the world. Major diseases caused by S. pneumoniae are otitis media, pneumonia, sepsis, and meningitis. Despite the availability of antibiotics and vaccines, pneumococcal infections still have high mortality rates, especially in risk groups. For this reason, there is an exceptionally e...

  19. Unit Cell Hypothesis for Streptococcus faecalis

    OpenAIRE

    Edelstein, Eugene M.; Rosenzweig, Martin S.; Daneo-Moore, Lolita; Higgins, Michael L.

    1980-01-01

    The mass doubling times of exponential-phase cultures of Streptococcus faecalis were varied from 30 to 110 min by omitting glutamine from a defined growth medium and providing different concentrations of glutamate (ranging from 300 to 14 ?g/ml). After Formalin fixation, cells were dried by the critical point method, and carbon-platinum replicas were prepared. The surface area and volume of cell poles seen in these replicas were estimated by a computer-assisted, three-dimensional reconstructio...

  20. Genome of Streptococcus oralis Strain Uo5?

    OpenAIRE

    Reichmann, Peter; Nuhn, Michael; Denapaite, Dalia; Brückner, Reinhold; Henrich, Bernhard; Maurer, Patrick; Rieger, Martin; Klages, Sven; Reinhard, Richard; Hakenbeck, Regine

    2011-01-01

    Streptococcus oralis, a commensal species of the human oral cavity, belongs to the Mitis group of streptococci, which includes one of the major human pathogens as well, S. pneumoniae. We report here the first complete genome sequence of this species. S. oralis Uo5, a high-level penicillin- and multiple-antibiotic-resistant isolate from Hungary, is competent for genetic transformation under laboratory conditions. Comparative and functional genomics of Uo5 will be important in understanding the...

  1. Effect of low-molecular-weight chitosans on the adhesive properties of oral streptococci.

    Science.gov (United States)

    Tarsi, R; Corbin, B; Pruzzo, C; Muzzarelli, R A

    1998-08-01

    It was previously shown that a low-molecular-weight chitosan and its derivatives N-carboxymethyl chitosan and imidazolyl chitosan inhibit Streptococcus mutans adsorption to hydroxyapatite. The ability of the same molecules to interfere with adhesive properties of other oral streptococci (Streptococcus sanguis, Streptococcus gordonii, Streptococcus constellatus, Streptococcus anginosus, Streptococcus intermedius, Streptococcus oralis, Streptococcus salivarius, Streptococcus vestibularis) was tested. When saliva-coated or -uncoated hydroxyapatite beads were treated with N-carboxymethyl chitosan, a reduction varying from 60% to 98% depending on strains was observed. Low-molecular-weight chitosans and imidazolyl chitosan did not have any effect. Growth in N-carboxymethyl chitosan-supplemented medium (final concentrations ranging from 20 to 500 micrograms.ml-1) caused a dose related reduction in the adsorption of all strains to hydroxyapatite and in their affinity towards xylene. No effect was observed with low-molecular-weight chitosans and imidazolyl chitosan. In contrast to what observed with S. mutans, the three polysaccharides did not affect detachment from hydroxyapatite beads and adherence to cheek epithelial cells of the other streptococci. These results suggest that low-molecular-weight chitosans and/or imidazolyl chitosan, selectively affecting S. mutans adsorption to hydroxyapatite, may be very interesting as potential anti-dental caries agents. PMID:10093536

  2. Surgical wound infection by Streptococcus pneumoniae after a cat-scratch disease.

    Science.gov (United States)

    Savini, Vincenzo; Cecinati, Valerio; Onofrillo, Daniela; Consilvio, Nicola Pietro; Polilli, Ennio; Crescenzi, Carlo; Fazii, Paolo; D'Antonio, Domenico

    2012-12-01

    Streptococcus pneumoniae (pneumococcus) is mostly known as an agent of meningitis and pneumonia. We present what is believed to be a previously unreported case of pneumococcal disease, involving an inguinal wound. A 10-year-old male patient underwent surgical removal of a cat-scratch disease-related enlarged groin lymph node; infection of the wound was soon observed, with multidrug-resistant S pneumoniae growing from the lesion discharge. This communication expands the spectrum of skin ulcer-infecting pathogens; in fact, although pneumococcus has been known to mostly affect central nervous system and airways, we observed a surgical wound infection by this organism. PMID:23222165

  3. Characterization of the Functional Domains of the SloR Metalloregulatory Protein in Streptococcus mutans

    OpenAIRE

    Haswell, Jeffrey R.; Pruitt, Benjamin W.; Cornacchione, Louis P.; Coe, Christopher L.; Smith, Evan G.; Spatafora, Grace. A

    2013-01-01

    Streptococcus mutans is a commensal member of the healthy plaque biofilm and the primary causative agent of dental caries. The present study is an investigation of SloR, a 25-kDa metalloregulatory protein that modulates genes responsible for S. mutans-induced cariogenesis. Previous studies of SloR homologues in other bacterial pathogens have identified three domains critical to repressor functionality: an N-terminal DNA-binding domain, a central dimerization domain, and a C-terminal FeoA (pre...

  4. Identification of Candidate Susceptibility and Resistance Genes of Mice Infected with Streptococcus suis Type 2

    OpenAIRE

    Rong, Jie; Zhang, Wei; Wang, Xiaohui; Fan, Hongjie; Lu, Chengping; Yao, Huochun

    2012-01-01

    Streptococcus suis type 2 (SS2) is an important swine pathogen and zoonosis agent. A/J mice are significantly more susceptible than C57BL/6 (B6) mice to SS2 infection, but the genetic basis is largely unknown. Here, alterations in gene expression in SS2 (strain HA9801)-infected mice were identified using Illumina mouse BeadChips. Microarray analysis revealed 3,692 genes differentially expressed in peritoneal macrophages between A/J and B6 mice due to SS2 infection. Between SS2-infected A/J an...

  5. Persistence of Streptococcus mutans in Stationary-Phase Batch Cultures and Biofilms†

    OpenAIRE

    Renye, John A.; Piggot, Patrick J.; Daneo-Moore, Lolita; Buttaro, Bettina A.

    2004-01-01

    Streptococcus mutans is a member of oral plaque biofilms and is considered the major etiological agent of dental caries. We have characterized the survival of S. mutans strain UA159 in both batch cultures and biofilms. Bacteria grown in batch cultures in a chemically defined medium, FMC, containing an excess of glucose or sucrose caused the pH to decrease to 4.0 at the entry into stationary phase, and they survived for about 3 days. Survival was extended up to 11 days when the medium containe...

  6. DETERMINACION DE LA PORTACION DE STREPTOCOCCUS AGALACTIAE (GRUPO B EN EMBARAZADAS DURANTE EL TERCER TRIMESTRE MEDIANTE INMUNOENSAYO

    Directory of Open Access Journals (Sweden)

    Fernando Abarzúa

    2002-01-01

    Full Text Available Dado que la sepsis neonatal por Streptococcus Grupo B es una enfermedad de alta letalidad, y considerando además que la portación de este germen en nuestra población de embarazadas se acerca a 20%, es que, resulta muy importante disponer de algún test rápido y confiable para realizar screening. Este estudio evalúa el rendimiento de un inmunoensayo para pesquisa de Streptococcus agalactiae en embarazadas sin factores de riesgo y a fines del tercer trimestre. Los resultados muestran una baja sensibilidad y un bajo valor predictivo positivo para este método, lo que no lo hace recomendable para su implementación clínicaNeonatal sepsis of early onset by group B Streptococcus has a high mortality rate. Twenty percent of our pregnant population have vaginal colonization by this bacterial agent, so clinical practice require a fast and efficient screening test. This report checks a Group B Streptococcus immunoassay screening test in the last trimester for pregnant women without risk factors. The low sensitivity and low positive predictive value of the test make it not recomendable for clinical practice

  7. Human Streptococcus agalactiae isolate in Nile tilapia (Oreochromis niloticus)

    Science.gov (United States)

    Streptococcus agalactiae, the Lancefield group B Streptococcus (GBS), long recognized as a mammalian pathogen, is an emerging pathogen to fish. We show that a GBS serotype Ia, multilocus sequence type ST-7 isolate from a human neonatal meningitis clinical case causes disease signs and mortality in N...

  8. Human Streptococcus agalactiae Isolate in Nile Tilapia (Oreochromis niloticus)

    OpenAIRE

    Joyce J. Evans; Klesius, Phillip H.; Pasnik, David J.; Bohnsack, John F.

    2009-01-01

    Streptococcus agalactiae, the Lancefield group B streptococcus (GBS) long recognized as a mammalian pathogen, is an emerging concern with regard to fish. We show that a GBS serotype Ia multilocus sequence type ST-7 isolate from a clinical case of human neonatal meningitis caused disease and death in Nile tilapia (Oreochromis niloticus).

  9. Sympathetic empyema arising from streptococcus anginosus splenic abscess

    Directory of Open Access Journals (Sweden)

    Wissa E

    2012-03-01

    Full Text Available We report a 52 year old male with a history splenic infarction, abdominal pain and shortness of breath. CT scanning revealed a splenic abcess and empyema. Cultures from both sites grew Streptococcus anginosus. These resolved with drainage and antibiotics. Physicians should consider Streptococcus species when confronted with a patient with splenic infarction.

  10. Problemas de resistencia en Streptococcus pyogenes / Antimicrobial resistance in Streptococcus pyogenes

    Scientific Electronic Library Online (English)

    Rossanna, Camponovo C..

    Full Text Available Los problemas de resistencia de Streptoco-ccus pyogenes son relativos a la adquisición de resistencia a macrólidos lo cual ocurre mediante dos mecanismos: modificación del sitio de acción en el ribosoma, resistencia tipo MLS B codificada por el gen erm que se asocia con resistencia a lincosamidas y [...] streptogramina B, y por eflujo activo codificado por gen mef con resistencia sólo a macrólidos, siendo éste el mecanismo más frecuentemente encontrado en este microorganismo. En Chile se han aislado cepas de Streptoco-ccus pyogenes resistentes a macrólidos desde 1994, con porcentaje de resistencia promedio en los últimos seis años de 7% en el área Metropolitana Abstract in english Streptococcus pyogenes resistance problems are refered to macrolides resistance which occurs by two mechanisms: modification of the target site in the ribosomes, MLS B resistance codified by gen erm and associated with resistance to lincosamines and streptogramin B, or by an active efflux mechanism [...] codified by gen mef which confers resistance to macrolides only, this being the most frequently described in this specie. In Chile Streptococcus pyogenes strains resistant to macrolides have been isolated since 1994, with rates of 7% in last six years at the Metropolitan area

  11. Sepsis neonatal tardía por Streptococcus pyogenes / Late neonatal sepsis caused by Streptococcus pyogenes

    Scientific Electronic Library Online (English)

    Mercedes, Fariñas Salto; Aída, De la Huerga López; Cristina, Menéndez Hernando; Ester Sanz, López.

    2011-08-01

    Full Text Available Actualmente, Streptococcus grupo A es una causa infrecuente de infección en el período neonatal. La descripción de casos de infección grave en el recién nacido es esporádica. Presentamos un recién nacido de 12 días de vida que acudió al servicio de urgencias por síndrome febril sin foco, que durante [...] su ingreso desarrolló afectación neurológica y sistémica. Describimos la presentación clínica, la evolución y el tratamiento. El aislamiento de Streptococcus grupo A en el hemocultivo confrma la sepsis tardía por este germen con probable meningitis asociada. Abstract in english Currently, the group A Streptococcus is a unusual cause of infection in the neonatal period. The description of cases of severe infection in the newborn is sporadic. We present a 12-days-old newborn attended at the emergency room for fever without focus, which developed neurological and systemic inv [...] olvement during admission. Clinical presentation, evolution and treatment are described. Blood culture isolation of group A Streptococcus confrmed late sepsis by this bacteria, probably with associated meningitis.

  12. Structural genomics studies of human caries pathogen Streptococcus mutans.

    Science.gov (United States)

    Li, Lanfen; Nan, Jie; Li, Dan; Brostromer, Erik; Wang, Zixi; Liu, Cong; Hou, Qiaoming; Fan, Xuexin; Ye, Zhaoyang; Su, Xiao-Dong

    2014-09-01

    Gram-positive bacterium Streptococcus mutans is the primary causative agent of human dental caries. To better understand this pathogen at the atomic structure level and to establish potential drug and vaccine targets, we have carried out structural genomics research since 2005. To achieve the goal, we have developed various in-house automation systems including novel high-throughput crystallization equipment and methods, based on which a large-scale, high-efficiency and low-cost platform has been establish in our laboratory. From a total of 1,963 annotated open reading frames, 1,391 non-membrane targets were selected prioritized by protein sequence similarities to unknown structures, and clustered by restriction sites to allow for cost-effective high-throughput conventional cloning. Selected proteins were over-expressed in different strains of Escherichia coli. Clones expressed soluble proteins were selected, expanded, and expressed proteins were purified and subjected to crystallization trials. Finally, protein crystals were subjected to X-ray analysis and structures were determined by crystallographic methods. Using the previously established procedures, we have so far obtained more than 200 kinds of protein crystals and 100 kinds of crystal structures involved in different biological pathways. In this paper we demonstrate and review a possibility of performing structural genomics studies at moderate laboratory scale. Furthermore, the techniques and methods developed in our study can be widely applied to conventional structural biology research practice. PMID:24474570

  13. Phenotypical characteristics of group B streptococcus in parturients.

    Science.gov (United States)

    Simoes, Jose Antonio; Alves, Valeria Moraes Neder; Fracalanzza, Sergio Eduardo Longo; de Camargo, Rodrigo Pauperio Soares; Mathias, Lenir; Milanez, Helaine Maria Besteti Pires; Brolazo, Eliane Melo

    2007-04-01

    Colonization by Group B Streptococcus (GBS) is highly prevalent among pregnant women, with prevalence rates ranging between 4% and 30%. The infection may be transmitted vertically and may result in serious neonatal consequences. In the period from November 2003 to May 2004, a cross-sectional study was carried out among 316 parturients at the Jundiaí Teaching Hospital to establish the prevalence of genital GBS colonization, to identify the factors associated with colonization and the characteristic phenotypes of these streptococci. Samples from rectal and vaginal areas were collected for selective culture in Todd-Hewitt broth. Susceptibility to 7 antimicrobial agents was tested using the antibiotic diffusion disk technique, and the isolated strains were classified using specific antisera. The prevalence of GBS colonization was 14.6%. No strain was resistant to penicillin, ampicillin, erythromycin or nitrofurantoin. The majority of strains were sensitive to cephalothin. Greatest resistance was to gentamicin (76.1%), followed by clindamycin (17.4%). The most frequent serotype was Ib (23.9%), followed by serotypes II and Ia (19.6% and 17.4%, respectively). There was no correlation between serotype and greater antimicrobial resistance. In conclusion, the prevalence of GBS in parturients was high and penicillin continues to be the drug of choice for intrapartum prophylaxis. The most frequent serotype (Ib) found in this study differs from those found in the majority of studies carried out in other countries, revealing the need to identify prevalent serotypes in each region so that specific vaccines can be designed. PMID:17625774

  14. Bacteriostatic effect of copaiba oil (Copaifera officinalis) against Streptococcus mutans.

    Science.gov (United States)

    Pieri, Fábio Alessandro; Mussi, Maria Carolina Martins; Fiorini, João Evangelista; Moreira, Maria Aparecida Scatamburlo; Schneedorf, José Mauricio

    2012-01-01

    This study evaluated the inhibitory activity of copaiba oil (Copaifera officinalis against the cariogenic microorganism, Streptococcus mutans. For such purpose, a minimum inhibition concentration test of copaiba oil against S. mutans was performed, using the serial dilution in broth technique, with a negative control, a positive control (0.12% chlorhexidine) and a 10% copaíba oil solution as a test. A minimum bactericidal concentration test with tubes presenting microbial inhibition was also conduced. In the minimum inhibitory concentration test, copaiba oil showed inhibition of bacterial growth at all concentrations tested up to 0.78 µL/mL of the 10% copaiba oil solution in the broth. In addition, the negative control had no inhibition, and the 0.12% chlorhexidine solution was effective up to 6.25 µL/mL in the broth. Copaiba oil showed a bacteriostatic activity against S. mutans at low concentrations, and could be a an option of phytotherapic agent to be used against cariogenic bacteria in the prevention of caries disease. PMID:22460312

  15. Streptococcus agalactiae en embarazadas: Prevalencia en el Hospital Nacional Alejandro Posadas / Streptococcus agalactiae in pregnant women: Prevalence at the Posadas Hospital

    Scientific Electronic Library Online (English)

    S., Di Bartolomeo; M., Gentile; G., Priore; S., Valle; A., Di Bella.

    2005-09-01

    Full Text Available Streptococcus agalactiae (estreptococo grupo B de Lancefield) es el microorganismo más frecuentemente involucrado en infección neonatal por transmisión vertical madre-feto. También es responsable de infecciones en mujeres embarazadas y adultos con enfermedades de base. El objetivo de este trabajo fu [...] e conocer la prevalencia de portación de S. agalactiae en mujeres embarazadas que concurrieron al Hospital Posadas y determinar la sensibilidad a penicilina, eritromicina y clindamicina de los aislamientos. De las 1203 gestantes estudiadas, se aisló S. agalactiae en 113 muestras, con una prevalencia de 9,39%. Se realizaron las pruebas de sensibilidad a 87 de los 113 aislamientos. Todos ellos resultaron sensibles a penicilina y únicamente 2 cepas fueron resistentes a eritromicina y clindamicina (mecanismo MLS constitutivo). Resaltamos la importancia de conocer la resistencia a estos dos últimos agentes, en el caso de mujeres alérgicas a los antibióticos beta-lactámicos. Abstract in english Streptococcus agalactiae (Lancefield group B Streptococcus), is the most frequently microorganism involved in neonatal infections through the mother-fetus vertical transmission. It is also responsible for infections in pregnant women, and adults with underlying diseases. The objective of this work w [...] as to know the S. agalactiae carrier prevalence in pregnant women who attended to Posadas Hospital, and to study the susceptibility pattern of the isolates to penicillin, erythromycin and clindamycin. From 1203 pregnant women studied, S. agalactiae was recovered in 113, which means a prevalence of 9.39%. Antimicrobial susceptibility was tested to 87 isolates. All of them were susceptible to penicillin, and only 2 isolates were resistant to erythromycin and clindamycin (constitutive MLS mechanism). We emphasize the importance of knowing these last resistance, in the case of beta-lactam antibiotics allergic women.

  16. Streptococcus agalactiae en embarazadas: Prevalencia en el Hospital Nacional Alejandro Posadas Streptococcus agalactiae in pregnant women: Prevalence at the Posadas Hospital

    Directory of Open Access Journals (Sweden)

    S. Di Bartolomeo

    2005-09-01

    Full Text Available Streptococcus agalactiae (estreptococo grupo B de Lancefield es el microorganismo más frecuentemente involucrado en infección neonatal por transmisión vertical madre-feto. También es responsable de infecciones en mujeres embarazadas y adultos con enfermedades de base. El objetivo de este trabajo fue conocer la prevalencia de portación de S. agalactiae en mujeres embarazadas que concurrieron al Hospital Posadas y determinar la sensibilidad a penicilina, eritromicina y clindamicina de los aislamientos. De las 1203 gestantes estudiadas, se aisló S. agalactiae en 113 muestras, con una prevalencia de 9,39%. Se realizaron las pruebas de sensibilidad a 87 de los 113 aislamientos. Todos ellos resultaron sensibles a penicilina y únicamente 2 cepas fueron resistentes a eritromicina y clindamicina (mecanismo MLS constitutivo. Resaltamos la importancia de conocer la resistencia a estos dos últimos agentes, en el caso de mujeres alérgicas a los antibióticos beta-lactámicos.Streptococcus agalactiae (Lancefield group B Streptococcus, is the most frequently microorganism involved in neonatal infections through the mother-fetus vertical transmission. It is also responsible for infections in pregnant women, and adults with underlying diseases. The objective of this work was to know the S. agalactiae carrier prevalence in pregnant women who attended to Posadas Hospital, and to study the susceptibility pattern of the isolates to penicillin, erythromycin and clindamycin. From 1203 pregnant women studied, S. agalactiae was recovered in 113, which means a prevalence of 9.39%. Antimicrobial susceptibility was tested to 87 isolates. All of them were susceptible to penicillin, and only 2 isolates were resistant to erythromycin and clindamycin (constitutive MLS mechanism. We emphasize the importance of knowing these last resistance, in the case of beta-lactam antibiotics allergic women.

  17. Prueba rápida para detección de Streptococcus pyogenes en faringoamigdalitis / Rapid test for detection of Streptococcus pyogenes in pharyngitis

    Scientific Electronic Library Online (English)

    Iván, Peñaranda Pérez; Miguel, Peñaranda Laura.

    Full Text Available El Streptococcus pyogenes es el agente más importante y frecuente de faringoamigdalitis bacteriana y por sus complicaciones asociadas, es importante su tratamiento específico, y por ello es necesario contar con pruebas rápidas y confiables para su identificación. Actualmente contamos con la "prueba [...] rápida" de su detección en exudado faríngeo, que se realiza en forma expedita en el consultorio. Estudiamos 16 pacientes con la sospecha de infección estreptocócica con esta prueba y en 62% fue positiva y confirmada por cultivos. Esta prueba puede resultar muy útil en la consulta ambulatoria y cuando no se cuenta con laboratorios cercanos. Abstract in english Streptococcal infection of the pharynges and tonsils is one of the more frequent causes of pediatric consultation and it is very important the rapid identification and treatment of the disease, to avoid the severe associated complications. We have done the "rapid strept test" in 16 suspected patient [...] s and found 62% of positive results, confirmed by cultures. This is an easy and rapid test for pediatric patients seen in remote areas.

  18. ?-Phosphoglucomutase contributes to aciduricity in Streptococcus mutans

    OpenAIRE

    Buckley, Andrew A.; Faustoferri, Roberta C.; Quivey, Robert G

    2014-01-01

    Streptococcus mutans encounters an array of sugar moieties within the oral cavity due to a varied human diet. One such sugar is ?-d-glucose 1-phosphate (?DG1P), which must be converted to glucose 6-phosphate (G6P) before further metabolism to lactic acid. The conversion of ?DG1P to G6P is mediated by ?-phosphoglucomutase, which has not been previously observed in any oral streptococci, but has been extensively characterized and the gene designated pgmB in Lactococcus lactis. An orthologue was...

  19. Ferrous iron transport in Streptococcus mutans

    Energy Technology Data Exchange (ETDEWEB)

    Evans, S.L.; Arcenaeux, J.E.L.; Byers, B.R.; Martin, M.E.; Aranha, H.

    1986-12-01

    Radioiron uptake from /sup 59/FeCl/sub 3/ by Streptococcus mutans OMZ176 was increased by anaerobiosis, sodium ascorbate, and phenazine methosulfate (PMS), although there was a 10-min lag before PMS stimulation was evident. The reductant ascorbate may have provided ferrous iron. The PMS was reduced by the cells, and the reduced PMS then may have generated ferrous iron for transport; reduced PMS also may have depleted dissolved oxygen. It was concluded that S. mutans transports only ferrous iron, utilizing reductants furnished by glucose metabolism to reduce iron prior to its uptake.

  20. Necrotizing fasciitis caused by group A streptococcus

    Directory of Open Access Journals (Sweden)

    Miki? Dragan

    2002-01-01

    Full Text Available The first case of the confirmed necrotizing fasciitis caused by Group A Streptococcus in Yugoslavia was presented. Male patient, aged 28, in good health, suddenly developed symptoms and signs of severe infective syndrome and intensive pain in the axillary region. Parenteral antibiotic, substitution and supportive therapy was conducted along with the radical surgical excision of the necrotizing tissue. The patient did not develop streptococcal toxic shock syndrome thanks to the early established diagnosis and timely applied aggressive treatment. He was released from the hospital as completely cured two months after the admission.

  1. Genome of Streptococcus oralis Strain Uo5?

    Science.gov (United States)

    Reichmann, Peter; Nuhn, Michael; Denapaite, Dalia; Brückner, Reinhold; Henrich, Bernhard; Maurer, Patrick; Rieger, Martin; Klages, Sven; Reinhard, Richard; Hakenbeck, Regine

    2011-01-01

    Streptococcus oralis, a commensal species of the human oral cavity, belongs to the Mitis group of streptococci, which includes one of the major human pathogens as well, S. pneumoniae. We report here the first complete genome sequence of this species. S. oralis Uo5, a high-level penicillin- and multiple-antibiotic-resistant isolate from Hungary, is competent for genetic transformation under laboratory conditions. Comparative and functional genomics of Uo5 will be important in understanding the evolution of pathogenesis among Mitis streptococci and their potential to engage in interspecies gene transfer. PMID:21460080

  2. Genome of Streptococcus oralis strain Uo5.

    Science.gov (United States)

    Reichmann, Peter; Nuhn, Michael; Denapaite, Dalia; Brückner, Reinhold; Henrich, Bernhard; Maurer, Patrick; Rieger, Martin; Klages, Sven; Reinhard, Richard; Hakenbeck, Regine

    2011-06-01

    Streptococcus oralis, a commensal species of the human oral cavity, belongs to the Mitis group of streptococci, which includes one of the major human pathogens as well, S. pneumoniae. We report here the first complete genome sequence of this species. S. oralis Uo5, a high-level penicillin- and multiple-antibiotic-resistant isolate from Hungary, is competent for genetic transformation under laboratory conditions. Comparative and functional genomics of Uo5 will be important in understanding the evolution of pathogenesis among Mitis streptococci and their potential to engage in interspecies gene transfer. PMID:21460080

  3. Bacteriostatic effect of copaiba oil (Copaifera officinalis) against Streptococcus mutans

    Scientific Electronic Library Online (English)

    Fábio Alessandro, Pieri; Maria Carolina Martins, Mussi; João Evangelista, Fiorini; Maria Aparecida Scatamburlo, Moreira; José Mauricio, Schneedorf.

    Full Text Available Este estudo avaliou a atividade inibitória do óleo de copaíba (Copaifera officinalis contra o microrganismo cariogênico, Streptococcus mutans. Para isso, foi realizado um teste de concentração mínima inibitória do óleo de copaíba contra S. mutans, utilizando a técnica de diluição seriada em caldo, c [...] om um controle negativo, um controle positivo (clorexidina a 0,12%) e uma solução de óleo de copaíba 10% como teste. Também foi conduzido um teste de concentração mínima bactericida com os tubos que apresentaram inibição microbiana. No teste de concentração inibitória mínima, o óleo de copaíba mostrou inibição do crescimento bacteriano em todas as concentrações testadas até 0,78 µL/mL da solução a 10% do óleo de copaíba no caldo. Além disso, o controle negativo não teve nenhuma inibição, e a solução de clorexidina 0,12% foi eficaz até 6,25 µL/mL no caldo. O óleo de copaíba mostrou uma atividade bacteriostática contra S. mutans em baixas concentrações, apresentando-se assim como uma opção de fitoterápico a ser utilizado contra bactérias cariogênicas na prevenção de cáries. Abstract in english This study evaluated the inhibitory activity of copaiba oil (Copaifera officinalis against the cariogenic microorganism, Streptococcus mutans. For such purpose, a minimum inhibition concentration test of copaiba oil against S. mutans was performed, using the serial dilution in broth technique, with [...] a negative control, a positive control (0.12% chlorhexidine) and a 10% copaíba oil solution as a test. A minimum bactericidal concentration test with tubes presenting microbial inhibition was also conduced. In the minimum inhibitory concentration test, copaiba oil showed inhibition of bacterial growth at all concentrations tested up to 0.78 µL/mL of the 10% copaiba oil solution in the broth. In addition, the negative control had no inhibition, and the 0.12% chlorhexidine solution was effective up to 6.25 µL/mL in the broth. Copaiba oil showed a bacteriostatic activity against S. mutans at low concentrations, and could be a an option of phytotherapic agent to be used against cariogenic bacteria in the prevention of caries disease.

  4. Características laboratoriais das ceratites e conjuntivites causadas por Streptococcus sp Laboratorial findings of Streptococcus keratitis and conjunctivitis

    Directory of Open Access Journals (Sweden)

    Helena Parente Solari

    2004-10-01

    Full Text Available OBJETIVOS: Analisar os resultados laboratoriais de conjuntivites e ceratites com cultura positiva para Streptococcus sp, avaliando a incidência das diferentes espécies e os dados dos antibiogramas. MÉTODOS: Estudo retrospectivo de revisão de prontuários de pacientes encaminhados ao laboratório de Doenças Externas do Departamento de Oftalmologia da UNIFESP com resultado de cultivo bacteriano positivo de córnea ou conjuntiva e com identificação de alguma cepa do gênero Streptococcus sp, no período de janeiro de 1995 a dezembro de 2001. Analisou-se idade do paciente, espécie de Streptococcus e os testes de sensibilidade aos seguintes antibióticos: cefalotina, amicacina, gentamicina, tobramicina, ciprofloxacina, lomefloxacina, ofloxacina, norfloxacina e vancomicina. RESULTADOS: As espécies mais encontradas foram Streptococcus pneumoniae e Streptococcus viridans. Com relação aos antibióticos, a sensibilidade foi maior à cefalotina, às quinolonas e à vancomicina. CONCLUSÕES: Considerando-se os antibióticos tópicos comercialmente disponíveis, as quinolonas apresentam melhor espectro de ação quando comparadas aos aminoglicosídios.PURPOSE: To evaluate laboratorial findings of Streptococcus keratitis and conjunctivitis, analyzing the different species and the results of bacterial susceptibility to an antibiotics. METHODS: Retrospective study of the records from the External Disease Laboratory of the Ophthalmology Department of the Federal University of São Paulo, with conjunctival or corneal positive bacterial culture for Streptococcus sp, between January 1995 and December 2001. The collected data were age, Streptococcus species and the bacterial susceptibility to the following antibiotics: cephalotin, amikacin, gentamicin, tobramicin, ciprofloxacin, lomefloxacin, ofloxacin, norfloxacin and vancomicin. RESULTS: The most frequent species were Streptococcus pneumoniae and Streptococcus viridans. Regarding bacterial susceptibility to antibiotics we found a higher susceptibility to the following antibiotics: cephalotin, quinolones and vancomicin. CONCLUSIONS: Considering the commercially available topic antibiotics, the quinolones presented better results when compared to the aminoglycosides.

  5. Erythromycine resistance in streptococcus pyogenes group a throat isolates in sukkur city

    International Nuclear Information System (INIS)

    To examine and evaluate the predominant and common etiologic agent(s) of pharyngitis in Sukkur city and to determine their current antibiotic susceptibility/resistance trends. Out of 257 throat samples, 149 positive for Streptococcus pyogenes Group A between November 2001 and May 2003 from adult population of Sukkur city were tested for their susceptibility to erythromycin, clindamycin, azithromycin and clairithromycin. The throat samples (swabs) were examined by Gram-stain, API system, and for presence of a hemolysis. Samples were further cultured on Muller Hinton agar for determination of antibiotic sensitivity patterns. The sensitivity was performed on only those samples which were positive for S. pyogenes. Of all throat isolates, 95% were predominantly resistant to erythromycin. Their sensitivity towards clindamycin was 30%, azithromycin 44% and clairithromycin 76% respectively. The current pharyngeal isolates of S. pyogenes exhibited frequent and alarmingly high erythromycin resistance which may be due to both intrinsic and acquired mechanisms. (author)

  6. The susceptibility of Streptococcus mutans to antibacterial photodynamic therapy: a comparison of two different photosensitizers and light sources

    Scientific Electronic Library Online (English)

    Neda, HAKIMIHA; Farzaneh, KHOEI; Abbas, BAHADOR; Reza, FEKRAZAD.

    2014-04-01

    Full Text Available Streptococcus mutans is the main etiological agent for dental caries. Recently, photodynamic therapy (PDT) has been introduced as a new modality in bacterial decontamination. Objective: This in vitro study was carried out to evaluate the susceptibility of Streptococcus mutans to antibacterial PDT [...] using two different photosensitizers and light sources. Material and Methods: Standard suspensions of S. mutans were exposed to laser light at 662 nm and Radachlorin® or LED 630 nm in combination with Toluidine blue O (TBO). Radiation-only groups, photosensitizer alone, and groups with no treatment were used as controls. Bacterial suspension from each treatment was subcultured onto the surface of Mueller-Hinton agar plates and bacterial growth was assessed. The results were analyzed by analysis of variance and Tukey test (p

  7. Acción de la inmunoglobulina A secretora en el proceso de adherencia del Streptococcus mutans al diente humano / Effect of secretory IgA on the adherence of Streptococcus Mutans on human teeth

    Scientific Electronic Library Online (English)

    Adriana Lucía, Chamorro-Jiménez; Andrea, Ospina-Cataño; Camilo, Arango-Rincón; Cecilia María, Martínez-Delgado.

    2013-07-01

    Full Text Available La caries dental, es una enfermedad infecciosa crónica que afecta a todas las edades, en la cual la presencia de Streptococcus mutans se constituye en una causa determinante más no suficiente para el desarrollo de dicha enfermedad, siendo éste el microorganismo más frecuentemente aislado en la cavid [...] ad oral. La Inmunoglobulina A secretora actúa como primer agente de defensa inmunológica de la superficie de la mucosa oral interfiriendo en la colonización bacteriana del diente a través de distintos mecanismos, sin embargo existen evidencias contradictorias sobre el verdadero papel en el desarrollo de la caries dental. El objetivo de este trabajo consiste en explicar mediante revisión bibliográfica desde 1990 hasta el 2009, la acción de la inmunoglobulina A secretora en el proceso de adherencia de Streptococcus mutans al diente humano. Abstract in english Dental caries is a chronic infectious disease that affects all age groups in which the presence of Streptococcus mutans constitutes a decisive but not sufficient cause for development of the disease, and is the most frequently isolated organism in the oral cavity. On other hand, secretory IgA (IgA-S [...] ) as the first immune defense agent that protects oral mucosal surface by impeding bacterial colonization of the tooth through different mechanisms; however there is contradictory evidence regarding the actual role of IgA-S and its relation with the development of dental caries. The purpose was to complete a review of the literature between 1990 to 2008o in order to explain the action of secretory immunoglobulin A during the adherence process of Streptococcus mutans to human teeth.

  8. Diverse Virulent Pneumophages Infect Streptococcus mitis

    Science.gov (United States)

    Ouennane, Siham; Leprohon, Philippe; Moineau, Sylvain

    2015-01-01

    Streptococcus mitis has emerged as one of the leading causes of bacterial endocarditis and is related to Streptococcus pneumoniae. Antibiotic resistance has also increased among strains of S. mitis and S. pneumoniae. Phages are being reinvestigated as alternatives to antibiotics for managing infections. In this study, the two virulent phages Cp-1 (Podoviridae) and Dp-1 (Siphoviridae), previously isolated from S. pneumoniae, were found to also infect S. mitis. Microbiological assays showed that both pneumophages could not only replicate in S. mitis but also produced more visible plaques on this host. However, the burst size and phage adsorption data were lower in S. mitis as compared to S. pneumoniae. A comparison of the genomes of each phage grown on both hosts produced identical nucleotide sequences, confirming that the same phages infect both bacterial species. We also discovered that the genomic sequence of podophage Cp-1 of the Félix d’Hérelle collection is different than the previously reported sequence and thus renamed SOCP. PMID:25692983

  9. Effects of Two Fluoride Varnishes and One Fluoride/Chlorhexidine Varnish on Streptococcus mutans and Streptococcus sobrinus Biofilm Formation in Vitro

    OpenAIRE

    Pinar Erdem, Arzu; Sepet, Elif; Kulekci, Güven; Trosola, Sule Can; Guven, Yegane

    2012-01-01

    Aims: The aim of this study was to evaluate and to compare the effect of two fluoride varnishes and one fluoride/chlorhexidine varnish on Streptococcus mutans and Streptococcus sobrinus biofilm formation, in vitro.

  10. Detection of Streptococcus pyogenes by Use of Illumigene Group A Streptococcus Assay

    OpenAIRE

    Henson, Amanda M.; Carter, Donna; Todd, Kathleen; Shulman, Stanford T; Zheng, Xiaotian

    2013-01-01

    The performance of the Illumigene group A Streptococcus assay was evaluated by comparing it to culture using 437 consecutive throat swabs. The Illumigene assay was also directly compared to PCR with 161 samples. This Illumigene assay is rapid and easy to perform. The assay also has high sensitivity (100%) compared to culture or PCR and high specificity (99.2%) compared to PCR. A total of 8.8% of the isolates were erythromycin resistant, and 6.9% were clindamycin resistant.

  11. Associations between salivary levels of Streptococcus mutans, Streptococcus sobrinus, lactobacilli, and caries experience in Kenyan adolescents

    DEFF Research Database (Denmark)

    Beighton, D; Manji, F; Baelum, V; Fejerskov, O; Johnson, N W; Wilton, J M

    1989-01-01

    Salivary levels of mutans streptococci (S. mutans and S. sobrinus) and lactobacilli were determined in a random sample of rural Kenyans between 15 and 19 years of age (n = 149). It is possible for the natural history of dental caries in this population to be studied since it is characterized by a limited access to conventional dental treatment. Using a short set of biochemical tests, we identified from seven to ten presumptive mutans streptococcus colonies--cultured from the saliva of each indiv...

  12. Isolation and characterization of unsaturated fatty acid auxotrophs of Streptococcus pneumoniae and Streptococcus mutans

    OpenAIRE

    Altabe, Silvia; López, Paloma; Mendoza , Diego

    2007-01-01

    Unsaturated fatty acid (UFA) biosynthesis is essential for the maintenance of membrane structure and function in many groups of anaerobic bacteria. Like Escherichia coli, the human pathogen Streptococcus pneumoniae produces straight-chain saturated fatty acids (SFA) and monounsaturated fatty acids. In E. coli UFA synthesis requires the action of two gene products, the essential isomerase/dehydratase encoded by fabA and an elongation condensing enzyme encoded by fabB. S. pneumoniae lacks both ...

  13. Delineation of Streptococcus dysgalactiae, its subspecies, and its clinical and phylogenetic relationship to Streptococcus pyogenes

    DEFF Research Database (Denmark)

    Jensen, Anders; Kilian, Mogens

    2011-01-01

    The close phylogenetic relationship of the important pathogen Streptococcus pneumoniae and several species of commensal streptococci, particularly Streptococcus mitis and Streptococcus pseudopneumoniae, and the recently demonstrated sharing of genes and phenotypic traits previously considered specific for S. pneumoniae hamper the exact identification of S. pneumoniae. Based on sequence analysis of 16S rRNA genes of a collection of 634 streptococcal strains, identified by multilocus sequence analysis, we detected a cytosine at position 203 present in all 440 strains of S. pneumoniae but replaced by an adenosine residue in all strains representing other species of mitis group streptococci. The S. pneumoniae-specific sequence signature could be demonstrated by sequence analysis or indirectly by restriction endonuclease digestion of a PCR amplicon covering the site. The S. pneumoniae-specific signature offers an inexpensive means for validation of the identity of clinical isolates and should be used as an integrated marker in the annotation procedure employed in 16S rRNA-based molecular studies of complex human microbiotas. This may avoid frequent misidentifications such as those we demonstrate to have occurred in previous reports and in reference sequence databases.

  14. Phagocytosis and Killing of Streptococcus pyogenes by Human Alveolar Macrophages

    OpenAIRE

    Gemmell, C. G.; Peterson, P.K.; Regelman, W.; Schmeling, D; Hoidal, J. R.; Quie, P G

    1981-01-01

    In contrast to human polymorphonuclear leukocytes and monocytes, alveolar macrophages were able to readily phagocytose and kill an M protein-positive Streptococcus pyogenes strain after opsonization in normal human serum.

  15. Streptococcus agalactiae infection in tilapia (Oreochromis niloticus

    Directory of Open Access Journals (Sweden)

    Suanyuk, N.

    2005-02-01

    Full Text Available Streptococcus agalactiae was isolated from cultured tilapia in Surat Thani province. Isolates were Gram-positive cocci, catalase negative, alpha-haemolytic and serogroup B. Streptococcal-infected fish showed various swimming abnormalities such as swimming on their side, erratic surface or bottom swimming including serpentine movement, exophthalmia and opacity. Internally, splenomegaly, ascites as well as pale liver discoloration were observed. Fish experimentally infected by peritoneal injection using 101 -108 CFU/ fish showed 20-90% mortality within 10 days and the LD50 was 3.60x101 - 1.72x107 CFU. Haematocrit, haemoglobin, plasma protein and blood cell values of infected and moribund fish were significantly decreased. Histopathological findings included the occurrence of inflammation, cells necrosis, infiltration of lymphocytes and the formation of granulomas in the infected organs.

  16. Induction of Cytokines by Glucosyltransferases of Streptococcus mutans

    OpenAIRE

    Chia, Jean-San; Lien, Huei-Ting; Hsueh, Po-Ren; Chen, Pei-Min; Sun, Andy; Chen, Jen-Yang

    2002-01-01

    Production of proinflammatory cytokines is implicated in the pathogenesis of viridans streptococcus-induced ?-streptococcal shock syndrome and infective endocarditis. Streptococcus mutans, one of the opportunistic pathogens causing infective endocarditis, was reported previously to stimulate monocytes and epithelial and endothelial cells in vitro to produce various cytokines. We found that glucosyltransferases (GTFs) GtfC and GtfD of S. mutans stimulated predominantly the production of interl...

  17. Streptococcus gordonii Modulates Candida albicans Biofilm Formation through Intergeneric Communication?

    OpenAIRE

    Bamford, Caroline V.; d'Mello, Anita; Nobbs, Angela H.; Dutton, Lindsay C.; Vickerman, M Margaret; Jenkinson, Howard F

    2009-01-01

    The fungus Candida albicans colonizes human oral cavity surfaces in conjunction with a complex microflora. C. albicans SC5314 formed biofilms on saliva-coated surfaces that in early stages of development consisted of ?30% hyphal forms. In mixed biofilms with the oral bacterium Streptococcus gordonii DL1, hyphal development by C. albicans was enhanced so that biofilms consisted of ?60% hyphal forms. Cell-cell contact between S. gordonii and C. albicans involved Streptococcus cell wall-anchored...

  18. Phosphate/hexose 6-phosphate antiport in Streptococcus lactis.

    OpenAIRE

    Maloney, P C; Ambudkar, S. V.; Thomas, J.(School of Physics and Astronomy, University of Birmingham, Birmingham, United Kingdom); Schiller, L

    1984-01-01

    After growth in appropriate media, resting cells of Streptococcus lactis 7962 showed a rapid exchange between external and internal pools of inorganic phosphate. This exchange was not found in other strains of S. lactis (ML3, 133, or K1) or in Streptococcus faecalis. Phosphate exchange in S. lactis 7962 did not require other anions or cations in the assay medium, nor was phosphate influx affected by the membrane potential and pH gradient formed during glycolysis. Thus, the exchange reaction w...

  19. Zerovalent bismuth nanoparticles inhibit Streptococcus mutans growth and formation of biofilm

    Directory of Open Access Journals (Sweden)

    Hernandez-Delgadillo R

    2012-04-01

    Full Text Available Rene Hernandez-Delgadillo1, Donaji Velasco-Arias2, David Diaz2, Katiushka Arevalo-Niño1, Marianela Garza-Enriquez1, Myriam A De la Garza-Ramos1, Claudio Cabral-Romero11Instituto de Biotecnologia, Centro de Investigacion y Desarrollo en Ciencias de la Salud, CIDICS, Facultad de Odontologia, Universidad Autonoma de Nuevo Leon, UANL, Monterrey, Nuevo Leon, 2Facultad de Quimica, Universidad Nacional Autonoma de Mexico, Distrito Federal, MexicoBackground and methods: Despite continuous efforts, the increasing prevalence of resistance among pathogenic bacteria to common antibiotics has become one of the most significant concerns in modern medicine. Nanostructured materials are used in many fields, including biological sciences and medicine. While some bismuth derivatives has been used in medicine to treat vomiting, nausea, diarrhea, and stomach pain, the biocidal activity of zerovalent bismuth nanoparticles has not yet been studied. The objective of this investigation was to analyze the antimicrobial activity of bismuth nanoparticles against oral bacteria and their antibiofilm capabilities.Results: Our results showed that stable colloidal bismuth nanoparticles had 69% antimicrobial activity against Streptococcus mutans growth and achieved complete inhibition of biofilm formation. These results are similar to those obtained with chlorhexidine, the most commonly used oral antiseptic agent. The minimal inhibitory concentration of bismuth nanoparticles that interfered with S. mutans growth was 0.5 mM.Conclusion: These results suggest that zerovalent bismuth nanoparticles could be an interesting antimicrobial agent to be incorporated into an oral antiseptic preparation.Keywords: zerovalent bismuth nanoparticles, antimicrobial agent, biofilm, Streptococcus mutans

  20. Phenotypical characteristics of group B streptococcus in parturients

    Directory of Open Access Journals (Sweden)

    Jose Antonio Simoes

    2007-04-01

    Full Text Available Colonization by Group B Streptococcus (GBS is highly prevalent among pregnant women, with prevalence rates ranging between 4% and 30%. The infection may be transmitted vertically and may result in serious neonatal consequences. In the period from November 2003 to May 2004, a cross-sectional study was carried out among 316 parturients at the Jundiaí Teaching Hospital to establish the prevalence of genital GBS colonization, to identify the factors associated with colonization and the characteristic phenotypes of these streptococci. Samples from rectal and vaginal areas were collected for selective culture in Todd-Hewitt broth. Susceptibility to 7 antimicrobial agents was tested using the antibiotic diffusion disk technique, and the isolated strains were classified using specific antisera. The prevalence of GBS colonization was 14.6%. No strain was resistant to penicillin, ampicillin, erythromycin or nitrofurantoin. The majority of strains were sensitive to cephalothin. Greatest resistance was to gentamicin (76.1%, followed by clindamycin (17.4%. The most frequent serotype was Ib (23.9%, followed by serotypes II and Ia (19.6% and 17.4%, respectively. There was no correlation between serotype and greater antimicrobial resistance. In conclusion, the prevalence of GBS in parturients was high and penicillin continues to be the drug of choice for intrapartum prophylaxis. The most frequent serotype (Ib found in this study differs from those found in the majority of studies carried out in other countries, revealing the need to identify prevalent serotypes in each region so that specific vaccines can be designed.

  1. Phenotypical characteristics of group B streptococcus in parturients

    Scientific Electronic Library Online (English)

    Jose Antonio, Simoes; Valeria Moraes Neder, Alves; Sergio Eduardo Longo, Fracalanzza; Rodrigo Pauperio Soares de, Camargo; Lenir, Mathias; Helaine Maria Besteti Pires, Milanez; Eliane Melo, Brolazo.

    2007-04-01

    Full Text Available Colonization by Group B Streptococcus (GBS) is highly prevalent among pregnant women, with prevalence rates ranging between 4% and 30%. The infection may be transmitted vertically and may result in serious neonatal consequences. In the period from November 2003 to May 2004, a cross-sectional study w [...] as carried out among 316 parturients at the Jundiaí Teaching Hospital to establish the prevalence of genital GBS colonization, to identify the factors associated with colonization and the characteristic phenotypes of these streptococci. Samples from rectal and vaginal areas were collected for selective culture in Todd-Hewitt broth. Susceptibility to 7 antimicrobial agents was tested using the antibiotic diffusion disk technique, and the isolated strains were classified using specific antisera. The prevalence of GBS colonization was 14.6%. No strain was resistant to penicillin, ampicillin, erythromycin or nitrofurantoin. The majority of strains were sensitive to cephalothin. Greatest resistance was to gentamicin (76.1%), followed by clindamycin (17.4%). The most frequent serotype was Ib (23.9%), followed by serotypes II and Ia (19.6% and 17.4%, respectively). There was no correlation between serotype and greater antimicrobial resistance. In conclusion, the prevalence of GBS in parturients was high and penicillin continues to be the drug of choice for intrapartum prophylaxis. The most frequent serotype (Ib) found in this study differs from those found in the majority of studies carried out in other countries, revealing the need to identify prevalent serotypes in each region so that specific vaccines can be designed.

  2. Implication of TLR- but Not of NOD2-Signaling Pathways in Dendritic Cell Activation by Group B Streptococcus Serotypes III and V

    OpenAIRE

    Lemire, Paul; Roy, David; Fittipaldi, Nahuel; Okura, Masatoshi; Takamatsu, Daisuke; Bergman, Eugenia; Segura, Mariela

    2014-01-01

    Group B Streptococcus (GBS) is an important agent of life-threatening invasive infection. It has been previously shown that encapsulated type III GBS is easily internalized by dendritic cells (DCs), and that this internalization had an impact on cytokine production. The receptors underlying these processes are poorly characterized. Knowledge on the mechanisms used by type V GBS to activate DCs is minimal. In this work, we investigated the role of Toll-like receptor (TLR)/MyD88 signaling pathw...

  3. Streptococcus mutans Extracellular DNA Is Upregulated during Growth in Biofilms, Actively Released via Membrane Vesicles, and Influenced by Components of the Protein Secretion Machinery

    OpenAIRE

    Liao, Sumei; Klein, Marlise I.; Heim, Kyle P.; Fan, Yuwei; Bitoun, Jacob P.; Ahn, San-Joon; Burne, Robert A; Koo, Hyun; Brady, L. Jeannine; Wen, Zezhang T.

    2014-01-01

    Streptococcus mutans, a major etiological agent of human dental caries, lives primarily on the tooth surface in biofilms. Limited information is available concerning the extracellular DNA (eDNA) as a scaffolding matrix in S. mutans biofilms. This study demonstrates that S. mutans produces eDNA by multiple avenues, including lysis-independent membrane vesicles. Unlike eDNAs from cell lysis that were abundant and mainly concentrated around broken cells or cell debris with floating open ends, eD...

  4. Clarithromycin Suppresses Human Respiratory Syncytial Virus Infection-Induced Streptococcus pneumoniae Adhesion and Cytokine Production in a Pulmonary Epithelial Cell Line

    OpenAIRE

    Nobuhiro Fujii; Tetsuo Himi; Hiroyuki Tsutsumi; Satoshi Hirakawa; Tamaki Okabayashi; Shin-ichi Yokota

    2012-01-01

    Human respiratory syncytial virus (RSV) sometimes causes acute and severe lower respiratory tract illness in infants and young children. RSV strongly upregulates proinflammatory cytokines and the platelet-activating factor (PAF) receptor, which is a receptor for Streptococcus pneumoniae, in the pulmonary epithelial cell line A549. Clarithromycin (CAM), which is an antimicrobial agent and is also known as an immunomodulator, significantly suppressed RSV-induced production of interleukin-6, int...

  5. The antibacterial effect of sage extract (Salvia officinalis mouthwash against Streptococcus mutans in dental plaque: a randomized clinical trial

    Directory of Open Access Journals (Sweden)

    Maryam Beheshti-Rouy

    2015-11-01

    Full Text Available Background and Objective:  The aim of the study was to evaluate the clinical effects of a mouthwash containing Sage (Salvia officinalis extracts on Streptococcus mutans (SM causing dental plaque in school-aged children.Material and Methods: A double blind clinical trial study was conducted in a dormitory on 70 girls aged 11-14 years having the same socioeconomic and oral hygiene conditions. These students were randomly divided into 2 groups; the first group (N=35 using Sage mouthwash, and the second group (N=35 using placebo mouthwash without active any ingredients. At the baseline, plaque samples obtained from the buccal surfaces of teeth were sent to laboratory to achieve SM colony count. These tests were reevaluated after 21 days of using the mouthwashes. Statistical data analysis was performed using t-student tests with p<0.05 as the level of significance.Results: Sage mouthwash significantly reduced the colony count (P=0.001. Average number of colonies in test group was 3900 per plaque sample at the baseline, and 300 after mouthwash application. In the control group, pre-test colony count was 4400 that was reduced to 4000; although this reduction wasn’t significant.Conclusion: The Sage mouthwash effectively reduced the number of Streptococcus mutans in dental plaque.Keywords: anti-bacterial agents; dental plaque; Salvia officinalis; Streptococcus mutans

  6. Extensive Adaptive Changes Occur in the Transcriptome of Streptococcus agalactiae (Group B Streptococcus) in Response to Incubation with Human Blood

    OpenAIRE

    Mereghetti, Laurent; Sitkiewicz, Izabela; Green, Nicole M.; Musser, James M.

    2008-01-01

    To enhance understanding of how Streptococcus agalactiae (group B streptococcus, GBS) adapts during invasive infection, we performed a whole-genome transcriptome analysis after incubation with whole human blood. Global changes occurred in the GBS transcriptome rapidly in response to blood contact following shift from growth in a rich laboratory medium. Most (83%) of the significantly altered transcripts were down-regulated after 30 minutes of incubation in blood, and all functional categories...

  7. Accuracy of Phenotypic and Genotypic Testing for Identification of Streptococcus pneumoniae and Description of Streptococcus pseudopneumoniae sp. nov.

    OpenAIRE

    Arbique, Judy C.; Poyart, Claire; Trieu-Cuot, Patrick; Quesne, Gilles; Carvalho, Maria da Glória S.; Steigerwalt, Arnold G; Morey, Roger E.; Jackson, Delois; Davidson, Ross J; Facklam, Richard R.

    2004-01-01

    We have identified an unusual group of viridans group streptococci that resemble Streptococcus pneumoniae. DNA-DNA homology studies suggested that a subset of these isolates represent a novel species that may be included in the S. oralis-S. mitis group of viridans group streptococci. We suggest that this novel species be termed Streptococcus pseudopneumoniae. A combination of phenotypic and genetic reactions allows its identification. S. pseudopneumoniae strains do not have pneumococcal capsu...

  8. Differentiation of banding patterns between Streptococcus mutans and Streptococcus sobrinus isolates in rep-PCR using ERIC primer

    OpenAIRE

    Tamami Okada; Kazuko Takada; Kou Fujita; Takuji Ikemi; Robert C. Osgood; Noel K. Childers; Michalek, Suzanne M.

    2011-01-01

    Streptococcus mutans and Streptococcus sobrinus are considered to be important bacterial species in the initiation of human dental caries. Therefore, the establishment of a reliable genotyping method to distinguish S. mutans from S. sobrinus is of central importance.We assessed the usefulness of repetitive extragenic palindromic polymerase chain reaction (rep-PCR) using ERIC primer banding patterns in differentiating S. mutans and S. sobrinus.Five S. mutans and two S. sobrinus prototype strai...

  9. Development of Primer Sets for Loop-Mediated Isothermal Amplification that Enables Rapid and Specific Detection of Streptococcus dysgalactiae, Streptococcus uberis and Streptococcus agalactiae

    Directory of Open Access Journals (Sweden)

    Deguo Wang

    2015-05-01

    Full Text Available Streptococcus dysgalactiae, Streptococcus uberis and Streptococcus agalactiae are the three main pathogens causing bovine mastitis, with great losses to the dairy industry. Rapid and specific loop-mediated isothermal amplification methods (LAMP for identification and differentiation of these three pathogens are not available. With the 16S rRNA gene and 16S-23S rRNA intergenic spacers as targets, four sets of LAMP primers were designed for identification and differentiation of S. dysgalactiae, S. uberis and S. agalactiae. The detection limit of all four LAMP primer sets were 0.1 pg DNA template per reaction, the LAMP method with 16S rRNA gene and 16S-23S rRNA intergenic spacers as the targets can differentiate the three pathogens, which is potentially useful in epidemiological studies.

  10. Stress responses in Streptococcus species and their effects on the host.

    Science.gov (United States)

    Nguyen, Cuong Thach; Park, Sang-Sang; Rhee, Dong-Kwon

    2015-11-01

    Streptococci cause a variety of diseases, such as dental caries, pharyngitis, meningitis, pneumonia, bacteremia, endocarditis, erysipelas, and necrotizing fasciitis. The natural niche of this genus of bacteria ranges from the mouth and nasopharynx to the skin, indicating that the bacteria will inevitably be subjected to environmental changes during invasion into the host, where it is exposed to the host immune system. Thus, the Streptococcus-host interaction determines whether bacteria are cleared by the host's defenses or whether they survive after invasion to cause serious diseases. If this interaction was to be deciphered, it could aid in the development of novel preventive and therapeutic agents. Streptococcus species possess many virulent factors, such as peroxidases and heat-shock proteins (HSPs), which play key roles in protecting the bacteria from hostile host environments. This review will discuss insights into the mechanism(s) by which streptococci adapt to host environments. Additionally, we will address how streptococcal infections trigger host stress responses; however, the mechanism by which bacterial components modulate host stress responses remains largely unknown. PMID:26502957

  11. Susceptibilidad antimicrobiana de Streptococcus pneumoniae colonizante de nasofaringe en niños colombianos con neumonía Antibiotic susceptibility of Streptococcus pneumoniae colonizing the nasopharynx of Colombian children with pneumonia

    Directory of Open Access Journals (Sweden)

    Aura Lucía Leal

    1997-04-01

    Full Text Available Streptococcus pneumoniae es uno de los principales agentes causales de infección respiratoria aguda (IRA en niños y su resistencia a antibióticos se ha incrementado en todo el mundo. En este estudio se determinaron los patrones de susceptibilidad a antimicrobianos de S. pneumoniae colonizante de las vías respiratorias altas en 272 niños hospitalizados por neumonía en dos hospitales de Santafé de Bogotá. Se aisló S. pneumoniae en 114 pacientes (42%. Se observó susceptibilidad disminuida a la penicilina en 19 aislamientos (17%, con sensibilidad intermedia en 12 (11% y franca resistencia en 7 (6%. Solo 1 de los 19 aislamientos resistentes a penicilina mostró también resistencia a la ceftriaxona. Se observó sensibilidad disminuida a la eritromicina en 3 aislamientos (3%, al cloranfenicol en 6 (5% y al cotrimoxazol (trimetoprima + sulfametoxazol en 46 (40%. Se encontró multirresistencia en 7 aislamientos (6%. El serotipo con sensibilidad disminuida a la penicilina que se halló con mayor frecuencia fue el 23F (68,4%. Se observó una asociación entre la edad, el uso previo de antibióticos y la colonización con S. pneumoniae con susceptibilidad disminuida a la penicilina o multirresistencia. Este estudio confirma la presencia de resistencia antimicrobiana de S. pneumoniae en Colombia y resalta la importancia del uso racional de los antibióticos y de la implementación de la vigilancia epidemiológica sobre este agente.Streptococcus pneumoniae is one of the principal causal agents of acute respiratory infection (ARI in children, and its resistance to antibiotics has increased worldwide. This study examined the patterns of susceptibility to antibiotics of S. pneumoniae that had colonized the upper respiratory tract of 272 children hospitalized for pneumonia in two hospitals in Santafé de Bogotá. S. pneumoniae was isolated from 114 patients (42%. Diminished susceptibility to penicillin was noted in 19 isolations (17%, with 12 (11% showing an intermediate level of sensitivity and 7 (6% outright resistance. Only 1 of the 19 isolates resistant to penicillin also showed resistance to ceftriaxone. There was diminished sensitivity to erythromycin in 3 isolations (3%, to chloramphenicol in 6 (5%, and to cotrimoxazole (trimethoprim + sulfamethoxazole in 46 (40%. Resistance to multiple drugs was found in 7 isolations (6%. The most commonly encountered penicillin-resistant serotype was 23F (68.4%. An association was observed among age, previous use of antibiotics, and colonization by S. pneumoniae with reduced penicillin susceptibility or multiple-drug resistance. This study confirmed the presence of antibiotic-resistant S. pneumoniae in Colombia and highlights the importance of the rational use of antibiotics and of the implementation of epidemiologic surveillance for this agent.

  12. Susceptibilidad antimicrobiana de Streptococcus pneumoniae colonizante de nasofaringe en niños colombianos con neumonía / Antibiotic susceptibility of Streptococcus pneumoniae colonizing the nasopharynx of Colombian children with pneumonia

    Scientific Electronic Library Online (English)

    Aura Lucía, Leal; Elizabeth, Castañeda.

    1997-04-01

    Full Text Available Streptococcus pneumoniae es uno de los principales agentes causales de infección respiratoria aguda (IRA) en niños y su resistencia a antibióticos se ha incrementado en todo el mundo. En este estudio se determinaron los patrones de susceptibilidad a antimicrobianos de S. pneumoniae colonizante de la [...] s vías respiratorias altas en 272 niños hospitalizados por neumonía en dos hospitales de Santafé de Bogotá. Se aisló S. pneumoniae en 114 pacientes (42%). Se observó susceptibilidad disminuida a la penicilina en 19 aislamientos (17%), con sensibilidad intermedia en 12 (11%) y franca resistencia en 7 (6%). Solo 1 de los 19 aislamientos resistentes a penicilina mostró también resistencia a la ceftriaxona. Se observó sensibilidad disminuida a la eritromicina en 3 aislamientos (3%), al cloranfenicol en 6 (5%) y al cotrimoxazol (trimetoprima + sulfametoxazol) en 46 (40%). Se encontró multirresistencia en 7 aislamientos (6%). El serotipo con sensibilidad disminuida a la penicilina que se halló con mayor frecuencia fue el 23F (68,4%). Se observó una asociación entre la edad, el uso previo de antibióticos y la colonización con S. pneumoniae con susceptibilidad disminuida a la penicilina o multirresistencia. Este estudio confirma la presencia de resistencia antimicrobiana de S. pneumoniae en Colombia y resalta la importancia del uso racional de los antibióticos y de la implementación de la vigilancia epidemiológica sobre este agente. Abstract in english Streptococcus pneumoniae is one of the principal causal agents of acute respiratory infection (ARI) in children, and its resistance to antibiotics has increased worldwide. This study examined the patterns of susceptibility to antibiotics of S. pneumoniae that had colonized the upper respiratory trac [...] t of 272 children hospitalized for pneumonia in two hospitals in Santafé de Bogotá. S. pneumoniae was isolated from 114 patients (42%). Diminished susceptibility to penicillin was noted in 19 isolations (17%), with 12 (11%) showing an intermediate level of sensitivity and 7 (6%) outright resistance. Only 1 of the 19 isolates resistant to penicillin also showed resistance to ceftriaxone. There was diminished sensitivity to erythromycin in 3 isolations (3%), to chloramphenicol in 6 (5%), and to cotrimoxazole (trimethoprim + sulfamethoxazole) in 46 (40%). Resistance to multiple drugs was found in 7 isolations (6%). The most commonly encountered penicillin-resistant serotype was 23F (68.4%). An association was observed among age, previous use of antibiotics, and colonization by S. pneumoniae with reduced penicillin susceptibility or multiple-drug resistance. This study confirmed the presence of antibiotic-resistant S. pneumoniae in Colombia and highlights the importance of the rational use of antibiotics and of the implementation of epidemiologic surveillance for this agent.

  13. Antibiotic susceptibility of Streptococcus pneumoniae colonizing the nasopharynx of Colombian children with pneumonia Susceptibilidad antimicrobiana de Streptococcus pneumoniae colonizante de nasofaringe en niños colombianos con neumonía

    Directory of Open Access Journals (Sweden)

    Aura Lucía Leal

    1997-10-01

    Full Text Available Streptococcus pneumoniae is one of the principal causal agents of acute respiratory infection (ARI in children, and its resistance to antibiotics has increased worldwide. This study examined the patterns of susceptibility to antibiotics of S. pneumoniae that had colonized the upper respiratory tract of 272 children hospitalized for pneumonia in two hospitals in Santafé de Bogotá. S. pneumoniae was isolated from 114 patients (42%. Diminished susceptibility to penicillin was noted in 19 isolates (17%, with 12 (11% having an intermediate level of sensitivity and 7 (6% showing outright resistance. Only 1 of the 19 isolates resistant to penicillin also showed resistance to ceftriaxone. There was diminished sensitivity to erythromycin in 3 isolates (3%, to chloramphenicol in 6 (5%, and to co-trimoxazole (trimethoprim + sulfamethoxazole in 46 (40%. Resistance to multiple drugs was found in 7 isolates (6%. The most commonly encountered penicillin-resistant serotype was 23F (68.4%. An association was observed between age, prior use of antibiotics, and colonization by S. pneumoniae with reduced penicillin sensitivity or multiple-drug resistance. This study confirmed the presence of antibiotic-resistant S. pneumoniae in Colombia and highlights the importance of the rational use of antibiotics and of the implementation of epidemiologic surveillance for this agent.Streptococcus pneumoniae es uno de los principales agentes causales de infección respiratoria aguda (IRA en niños y su resistencia a antibióticos se ha incrementado en todo el mundo. En este estudio se determinaron los patrones de susceptibilidad a antimicrobianos de S. pneumoniae colonizante de las vías respiratorias altas en 272 niños hospitalizados por neumonía en dos hospitales de Santafé de Bogotá. Se aisló S. pneumoniae en 114 pacientes (42%. Se observó susceptibilidad disminuida a la penicilina en 19 aislamientos (17%, con sensibilidad intermedia en 12 (11% y franca resistencia en 7 (6%. Solo 1 de los 19 aislamientos resistentes a penicilina mostró también resistencia a la ceftriaxona. Se observó sensibilidad disminuida a la eritromicina en 3 aislamientos (3%, al cloranfenicol en 6 (5% y al cotrimoxazol (trimetoprima + sulfametoxazol en 46 (40%. Se encontró multirresistencia en 7 aislamientos (6%. El serotipo con sensibilidad disminuida a la penicilina que se halló con mayor frecuencia fue el 23F (68.4%. Se observó una asociación entre la edad, el uso previo de antibióticos y la colonización con S. pneumoniae con susceptibilidad disminuida a la penicilina o multirresistencia. Este estudio confirma la presencia de resistencia antimicrobiana de S. pneumoniae en Colombia y resalta la importancia del uso racional de los antibióticos y de la implementación de la vigilancia epidemiológica sobre este agente.

  14. Antibiotic susceptibility of Streptococcus pneumoniae colonizing the nasopharynx of Colombian children with pneumonia / Susceptibilidad antimicrobiana de Streptococcus pneumoniae colonizante de nasofaringe en niños colombianos con neumonía

    Scientific Electronic Library Online (English)

    Aura Lucía, Leal; Elizabeth, Castañeda.

    1997-10-01

    Full Text Available Streptococcus pneumoniae es uno de los principales agentes causales de infección respiratoria aguda (IRA) en niños y su resistencia a antibióticos se ha incrementado en todo el mundo. En este estudio se determinaron los patrones de susceptibilidad a antimicrobianos de S. pneumoniae colonizante de la [...] s vías respiratorias altas en 272 niños hospitalizados por neumonía en dos hospitales de Santafé de Bogotá. Se aisló S. pneumoniae en 114 pacientes (42%). Se observó susceptibilidad disminuida a la penicilina en 19 aislamientos (17%), con sensibilidad intermedia en 12 (11%) y franca resistencia en 7 (6%). Solo 1 de los 19 aislamientos resistentes a penicilina mostró también resistencia a la ceftriaxona. Se observó sensibilidad disminuida a la eritromicina en 3 aislamientos (3%), al cloranfenicol en 6 (5%) y al cotrimoxazol (trimetoprima + sulfametoxazol) en 46 (40%). Se encontró multirresistencia en 7 aislamientos (6%). El serotipo con sensibilidad disminuida a la penicilina que se halló con mayor frecuencia fue el 23F (68.4%). Se observó una asociación entre la edad, el uso previo de antibióticos y la colonización con S. pneumoniae con susceptibilidad disminuida a la penicilina o multirresistencia. Este estudio confirma la presencia de resistencia antimicrobiana de S. pneumoniae en Colombia y resalta la importancia del uso racional de los antibióticos y de la implementación de la vigilancia epidemiológica sobre este agente. Abstract in english Streptococcus pneumoniae is one of the principal causal agents of acute respiratory infection (ARI) in children, and its resistance to antibiotics has increased worldwide. This study examined the patterns of susceptibility to antibiotics of S. pneumoniae that had colonized the upper respiratory trac [...] t of 272 children hospitalized for pneumonia in two hospitals in Santafé de Bogotá. S. pneumoniae was isolated from 114 patients (42%). Diminished susceptibility to penicillin was noted in 19 isolates (17%), with 12 (11%) having an intermediate level of sensitivity and 7 (6%) showing outright resistance. Only 1 of the 19 isolates resistant to penicillin also showed resistance to ceftriaxone. There was diminished sensitivity to erythromycin in 3 isolates (3%), to chloramphenicol in 6 (5%), and to co-trimoxazole (trimethoprim + sulfamethoxazole) in 46 (40%). Resistance to multiple drugs was found in 7 isolates (6%). The most commonly encountered penicillin-resistant serotype was 23F (68.4%). An association was observed between age, prior use of antibiotics, and colonization by S. pneumoniae with reduced penicillin sensitivity or multiple-drug resistance. This study confirmed the presence of antibiotic-resistant S. pneumoniae in Colombia and highlights the importance of the rational use of antibiotics and of the implementation of epidemiologic surveillance for this agent.

  15. Eritrodermia con bacteriemia por Streptococcus dysgalactiae subespecie equisimilis en un paciente pediátrico: reporte de un caso y revisión de la literatura / Streptococcus dysgalactiae subspecies equisimilis bacteremic erythroderma in a pediatric patient: a case report and review of literature

    Scientific Electronic Library Online (English)

    Miguel A, Pantoja; Luis, Delpiano; Gia, Haquin.

    2014-10-01

    Full Text Available Las infecciones por estreptococos piógenos, comunes en la edad pediátrica, muestran en los últimos años un aumento en la identificación de grupos no A o B. Presentamos el caso de una niña de 6 años, con historia de fiebre de cinco días de evolución asociado a una lesión eritrodérmica con hemocultivo [...] s positivos a Streptococcus dysgalactiae subspecies equisimilis (confirmado por biología molecular-genotipificación). Recibió terapia antimicrobiana por 14 días con ß-lactámicos con una evolución favorable. Este estreptococo ß-hemolítico, presenta antígenos del grupo A, C y G de Lancefield y una gran similitud con Streptococcus pyogenes en relación a los factores de virulencia. Más frecuentemente aislado en adultos mayores, existen pocos casos descritos en población pediátrica. El tratamiento de primera línea es con ß-lactámicos, para los cuales no hay reportes de resistencia antimicrobiana. Abstract in english Infections caused by pyogenic streptococci are commons in pediatric ages. However, in the last decades there has been an increase in the isolation of no A or B Streptococci. We report a case of a 6 years old girl, who presents fever for 5 days and erythroderma. Streptococcus dysgalactiae subspecies [...] equisimilis was isolated from blood cultures. She receives antibiotics for 14 days with ß-lactams with a good clinic evolution with normalization of the inflammatory parameters. This agent ß-hemolítico presents antigens of Lancefield groups A, C and G, and a great similitude regarding virulence factors, with Streptococcus pyogenes. Frequently in old patients, few reported cases in pediatric population. First line treatment remains ß-lactam antibiotics for which there are no reports of increasing resistance.

  16. Agent engineering

    CERN Document Server

    Liu, Jiming; Zhong, Ning; Wang, Patrick S P

    2001-01-01

    Agent engineering concerns the development of autonomous computational or physical entities capable of perceiving, reasoning, adapting, learning, cooperating and delegating in a dynamic environment. It is one of the most promising areas of research and development in information technology, computer science and engineering. This book addresses some of the key issues in agent engineering: What is meant by "autonomous agents"? How can we build agents with autonomy? What are the desirable capabilities of agents with respect to surviving (they will not die) and living (they will furthermore enjoy

  17. In vitro biofilm forming potential of Streptococcus suis isolated from human and swine in China

    Scientific Electronic Library Online (English)

    Guo, Dawei; Wang, Liping; Lu, Chengping.

    2012-09-01

    Full Text Available Streptococcus suis is a swine pathogen and also a zoonotic agent. The formation of bio?lms allows S. suis to become persistent colonizers and resist clearance by the host immune system and antibiotics. In this study, biofilm forming potentials of various S. suis strains were characterized by confoca [...] l laser scanning microscopy (CLSM), scanning electron microscopy (SEM) and tissue culture plates stained with crystal violet. In addition, the effects of five antimicrobial agents on biofilm formation were assayed in this study. S. suis produced biofilms on smooth and rough surface. The nutritional contents including glucose and NaCl in the growth medium modulated biofilm formation. There was a significant difference in their biofilm-forming ability among all 46 S. suis strains. The biofilm-forming potential of S. suis serotype 9 was stronger than type 2 and all other types. However, biofilm formation was inhibited by five commonly used antimicrobial agents, penicillin, erythromycin, azithromycin, ciprofloxacin, and ofloxacin at subinhibitory concentrations, among which inhibition of ciprofloxacin and ofloxacin was stronger than that of other three antimicrobial agents.Our study provides a detailed analysis of biofilm formation potential in S. suis, which is a step towards understanding its role in pathogenesis, and eventually lead to a better understanding of how to eradicate S. suis growing as biofilms with antibiotic therapy.

  18. Group B Streptococcus Engages an Inhibitory Siglec through Sialic Acid Mimicry to Blunt Innate Immune and Inflammatory Responses In Vivo

    OpenAIRE

    Chang, Yung-Chi; Olson, Joshua; Beasley, Federico C; Tung, Christine; Zhang, Jiquan; Crocker, Paul R.; Varki, Ajit; Nizet, Victor

    2014-01-01

    Group B Streptococcus (GBS) is a common agent of bacterial sepsis and meningitis in newborns. The GBS surface capsule contains sialic acids (Sia) that engage Sia-binding immunoglobulin-like lectins (Siglecs) on leukocytes. Here we use mice lacking Siglec-E, an inhibitory Siglec of myelomonocytic cells, to study the significance of GBS Siglec engagement during in vivo infection. We found GBS bound to Siglec-E in a Sia-specific fashion to blunt NF-?B and MAPK activation. As a consequence, Sigle...

  19. In vitro activities of 12 orally administered antimicrobial agents against four species of bacterial respiratory pathogens from U.S. Medical Centers in 1992 and 1993.

    OpenAIRE

    Barry, A L; PFALLER, M.A.; Fuchs, P C; Packer, R R

    1994-01-01

    Clinical isolates of Haemophilus influenzae, Streptococcus pneumoniae, Streptococcus pyogenes, and Moraxella catarrhalis were gathered from 19 different clinical laboratories throughout the continental United States. The in vitro activities of 12 orally administered antimicrobial agents were compared by broth microdilution tests with 3,151 bacterial isolates. Among 890 H. influenzae isolates, 30% were capable of producing beta-lactamase enzymes (12 to 41% in different medical centers). Most o...

  20. Prophage Lysin Ply30 Protects Mice from Streptococcus suis and Streptococcus equi subsp. zooepidemicus Infections.

    Science.gov (United States)

    Tang, Fang; Li, Dezhi; Wang, Haojin; Ma, Zhe; Lu, Chengping; Dai, Jianjun

    2015-11-01

    Streptococcus suis and Streptococcus equi subsp. zooepidemicus are capable of infecting humans and various animals, causing significant problems for the worldwide swine industry. As antibiotic resistance has increased, lysosomal enzymes encoded by phages have shown potential for use against pathogenic bacteria. In this study, a novel bacteriophage lysin, Ply30, encoded by the S. suis prophage phi30c, was recombinantly expressed and purified. Ply30 showed high bacteriolysis activity on S. suis and S. equi subsp. zooepidemicus in vitro. The ratio of the optical density at 600 nm (OD600) with treatment versus the OD600 with no treatment for most tested S. suis and S. equi subsp. zooepidemicus strains decreased from 1 to <0.3 and <0.5, respectively, within 1 h. The results of plate viability assays showed that treated bacteria suffered a 1- to 2-log decrease in CFU within 1 h. The optimal concentration of Ply30 was 50 ?g/ml, and the optimal pH was 7. Moreover, Ply30 maintained high activity over a wide pH range (pH 6 to 10). The MICs of Ply30 against Streptococcus strains ranged from 16 to 512 ?g/ml. In vivo, a 2-mg dose of Ply30 protected 90% (9/10 mice) of mice from infection with S. equi subsp. zooepidemicus and 80% (8/10 mice) of mice from infection with S. suis. Seven days after lysin Ply30 treatment, bacterial loads were significantly decreased in all tested organs and blood compared with those at 1 h postinfection without Ply30 treatment. Ply30 showed in vitro and in vivo antimicrobial efficiency and protected mice against two kinds of bacterial infections, indicating that Ply30 may be an effective therapeutic against streptococci. PMID:26253669

  1. Coaggregation of Streptococcus sanguis and other streptococci with Candida albicans.

    Science.gov (United States)

    Jenkinson, H F; Lala, H C; Shepherd, M G

    1990-01-01

    Thirteen strains of viridans group streptococci and two strains of other streptococci were tested for coaggregation with Candida albicans. Streptococcus sanguis strains generally exhibited low levels of adherence to 28 degrees C-grown exponential-phase yeast cells, but starvation of yeast cells for glucose at 37 degrees C (or at 28 degrees C) increased their coaggregating activity with these streptococci by at least tenfold. This was a property common to four C. albicans strains tested, two of which were able to form mycelia (6406 and MEN) and two of which were not (MM2002 and CA2). The expression of the coaggregation adhesin during yeast cell starvation was inhibited by addition of trichodermin or amphotericin B. The strains of S. sanguis, Streptococcus gordonii, and Streptococcus oralis tested for coaggregating activity encompassed a diverse range of physiological and morphological types, yet all exhibited saturable coaggregation with starved C. albicans cells. There was no correlation of cell surface hydrophobicity, of either yeast or streptococcal cells, with their abilities to coaggregate. Strains of Streptococcus anginosus also coaggregated with starved yeast cells; Streptococcus salivarius and Streptococcus pyogenes coaggregated to a lesser degree with C. albicans, and the coaggregation with S. pyogenes was not promoted by yeast cell starvation; Streptococcus mutans and Enterococcus faecalis did not coaggregate with yeast. The coaggregation reactions of S. sanguis and S. gordonii with C. albicans were inhibited by EDTA and by heat or protease treatment of the yeast cells and were not reversible by the addition of lactose or other simple sugars. These observations extend the range of intergeneric coaggregations that are known to occur between oral microbes and suggest that coaggregations of C. albicans with viridans group streptococci may be important for colonization of oral surfaces by the yeast. PMID:2182544

  2. Parallel Evolution of Streptococcus pneumoniae and Streptococcus mitis to Pathogenic and Mutualistic Lifestyles

    DEFF Research Database (Denmark)

    Kilian, Mogens; Riley, David R

    2014-01-01

    UNLABELLED: The bacterium Streptococcus pneumoniae is one of the leading causes of fatal infections affecting humans. Intriguingly, phylogenetic analysis shows that the species constitutes one evolutionary lineage in a cluster of the otherwise commensal Streptococcus mitis strains, with which humans live in harmony. In a comparative analysis of 35 genomes, including phylogenetic analyses of all predicted genes, we have shown that the pathogenic pneumococcus has evolved into a master of genomic flexibility while lineages that evolved into the nonpathogenic S. mitis secured harmonious coexistence with their host by stabilizing an approximately 15%-reduced genome devoid of many virulence genes. Our data further provide evidence that interspecies gene transfer between S. pneumoniae and S. mitis occurs in a unidirectional manner, i.e., from S. mitis to S. pneumoniae. Import of genes from S. mitis and other mitis, anginosus, and salivarius group streptococci ensured allelic replacements and antigenic diversification and has been driving the evolution of the remarkable structural diversity of capsular polysaccharides of S. pneumoniae. Our study explains how the unique structural diversity of the pneumococcal capsule emerged and conceivably will continue to increase and reveals a striking example of the fragile border between the commensal and pathogenic lifestyles. While genomic plasticity enabling quick adaptation to environmental stress is a necessity for the pathogenic streptococci, the commensal lifestyle benefits from stability. IMPORTANCE: One of the leading causes of fatal infections affecting humans, Streptococcus pneumoniae, and the commensal Streptococcus mitis are closely related obligate symbionts associated with hominids. Faced with a shortage of accessible hosts, the two opposing lifestyles evolved in parallel. We have shown that the nonpathogenic S. mitis secured harmonious coexistence with its host by stabilizing a reduced genome devoid of many virulence genes. Meanwhile, the pathogenic pneumococcus evolved into a master of genomic flexibility and imports genes from S. mitis and other related streptococci. This process ensured antigenic diversification and has been driving the evolution of the remarkable structural diversity of capsular polysaccharides of S. pneumoniae, which conceivably will continue to increase and present a challenge to disease prevention.

  3. Streptococcus salivarius urease: genetic and biochemical characterization and expression in a dental plaque streptococcus.

    OpenAIRE

    Y.Y CHEN; Clancy, K A; Burne, R A

    1996-01-01

    The hydrolysis of urea by urease enzyme of oral bacteria is believed to have a major impact on oral microbial ecology and to be intimately involved in oral health and diseases. To begin to understand the biochemistry and genetics of oral ureolysis, a study of the urease of Streptococcus salivarius, a highly ureolytic organism which is present in large numbers on the soft tissues of the oral cavity, has been initiated. By using as a probe a 0.6-kpb internal fragment of the S. salivarius 57.I u...

  4. Endocarditis por Streptococcus equi subsp. zooepidemicus / Streptococcus equi subsp. Zooepidemicus endocarditis

    Scientific Electronic Library Online (English)

    Iago, Villamil; Marta, Serrano; Elisabeth, Prieto.

    2015-04-01

    Full Text Available Las especies Streptococcus equi subsp. equi y S. equi subsp. zooepidemicus son especies zoonóticas típicamente patógenas de animales, especialmente en caballos. Es una causa excepcional de enfermedad en humanos. Presentamos un caso de endocarditis por S. equi subsp. zooepidemicus tras un contacto co [...] n equinos, con buena evolución con tratamiento antibiótico. Abstract in english Zoonotic infections with S. equi subsp. zooepidemicus have been reported occasionally in individuáis with exposure to farm animals, especially horses. They exceptionally present as a human pathogen. We present a S. equi subsp. zooepidemicus well documented endocarditis after a horse's female genital [...] tract contact, and excellent surveillance with exclusive antibiotic management.

  5. Agentes de información / Information Agents

    Scientific Electronic Library Online (English)

    Alfonso, López Yepes; Rodrigo, Sánchez Jiménez; José Ramón, Pérez Agüera.

    2005-12-01

    Full Text Available Este artículo realiza un repaso sobre las tipologías de agentes de información y describe aspectos como movilidad, racionalidad y adaptatividad, y el ajuste final de estos conceptos a entornos distribuidos como Internet, donde este tipo de agentes tienen un amplio grado de aplicación. Asimismo, se p [...] ropone una arquitectura de agentes para un sistema multiagente de recuperación de información donde se aplica un paradigma documental basado en el concepto de ciclo documental. Abstract in english This article summarizes the main information agent types reflecting on issues such as mobility, rationality, adaptability and the final adjustment of this concepts to distributed environments such as the Internet, where this kind of agents has wide range application. Likewise, an information agent a [...] rchitecture is proposed to create a multi-agent information retrieval system in which a documentary paradigm based on the documentary cycle is developed.

  6. Agentes de información Information Agents

    Directory of Open Access Journals (Sweden)

    Alfonso López Yepes

    2005-12-01

    Full Text Available Este artículo realiza un repaso sobre las tipologías de agentes de información y describe aspectos como movilidad, racionalidad y adaptatividad, y el ajuste final de estos conceptos a entornos distribuidos como Internet, donde este tipo de agentes tienen un amplio grado de aplicación. Asimismo, se propone una arquitectura de agentes para un sistema multiagente de recuperación de información donde se aplica un paradigma documental basado en el concepto de ciclo documental.This article summarizes the main information agent types reflecting on issues such as mobility, rationality, adaptability and the final adjustment of this concepts to distributed environments such as the Internet, where this kind of agents has wide range application. Likewise, an information agent architecture is proposed to create a multi-agent information retrieval system in which a documentary paradigm based on the documentary cycle is developed.

  7. Incomplete Kawasaki disease associated with complicated Streptococcus pyogenes pneumonia: A case report

    OpenAIRE

    Leahy, Timothy Ronan; Cohen, Eyal; Allen, Upton D

    2012-01-01

    A three-year-old boy presented with community-acquired pneumonia complicated by empyema. Streptococcus pyogenes (group A streptococcus) was identified on culture of the pleural fluid. The patient improved with antibiotic therapy and drainage of the empyema.

  8. Spontaneous bacterial peritonitis caused by Streptococcus bovis: case report and review of the literature

    Scientific Electronic Library Online (English)

    Rosmari, Hörner; Adenilde, Salla; Loiva Otonelli de, Oliveira; Nara Lucia Frasson Dal, Forno; Roselene Alves, Righi; Vanessa Oliveira, Domingues; Fabiane, Rigatti; Letícia Eichstaedt, Mayer.

    2010-06-01

    Full Text Available Spontaneous bacterial peritonitis (SBP) is a frequent and severe complication that occurs in patient with cirrhosis and ascites. It occurs in 10% to 30% of patients admitted to hospital. The organisms that cause SBP are predominantly enteric. Escherichia coli is the most frequent recovered pathogen, [...] and Gram-positive bacteria, mainly Staphylococcus spp., are being considered an emerging causative agent of SBP. Streptococcus bovis that may be found as part of the commensal bowel flora in about 10% of healthy adults constitute an uncommon cause of peritonitis that was first reported in 1994. We describe the first case of SBP at the University Hospital of Santa Maria (HUSM) caused by S. bovis, resistant to the antibiotics erythromycin and clindamycin (inducible clindamycin resistance detected by disk diffusion test using the D-zone test).

  9. Platelet-Dependent Neutrophil Function Is Dysregulated by M Protein from Streptococcus pyogenes.

    Science.gov (United States)

    Hurley, Sinéad M; Kahn, Fredrik; Nordenfelt, Pontus; Mörgelin, Matthias; Sørensen, Ole E; Shannon, Oonagh

    2015-09-01

    Platelets are rapidly responsive sentinel cells that patrol the bloodstream and contribute to the host response to infection. Platelets have been reported to form heterotypic aggregates with leukocytes and may modulate their function. Here, we have investigated platelet-neutrophil complex formation and neutrophil function in response to distinct agonists. The endogenous platelet activator thrombin gave rise to platelet-dependent neutrophil activation, resulting in enhanced phagocytosis and bacterial killing. Streptococcus pyogenes is an important causative agent of severe infectious disease, which can manifest as sepsis and septic shock. M1 protein from S. pyogenes also mediated platelet-neutrophil complex formation; however, these neutrophils were dysfunctional and exhibited diminished chemotactic ability and bacterial killing. This reveals an important agonist-dependent neutrophil dysfunction during platelet-neutrophil complex formation and highlights the role of platelets during the immune response to streptococcal infection. PMID:26099589

  10. Comparison of inhibitory activity of bioactive molecules on the dextransucrase from Streptococcus mutans.

    Science.gov (United States)

    Lee, Choon Geun; Park, Jae Kweon

    2015-09-01

    The effect of chitosan with different molecular weights and other natural substances on dextransucrase (DSase) activity from a representative oral pathogen Streptococcus mutans was elucidated. Among other bioactive substances, amino-monosaccharides such as glucosamine, mannosamine, and galactosamine exerted the enzyme inhibitory activity over 95 % of DSase. The specified hydrolysates derived from the hydrolysis of high molecular weight chitosan (HMWC) designated to CTSN, CTSN-P, CTSN-B, and CTSN-S with different molecular weights ranging from 3 to 8 kDa showed the similar inhibitory activity toward DSase. Also, the hyaluronic acid (MW 8.9 kDa), sulfated chitin, and amino-monosaccharides demonstrated the significant activity, CTSN, CTSN-P, CTSN-B, and CTSN-S are of potent bioactive substances that can be prepared in the cheapest way compared with other molecules tested available for antibacterial agent useful for human oral health. PMID:26016785

  11. Negotiating Agents

    OpenAIRE

    Jonker, Catholijn M.; Delft University of Technology; Hindriks, Koen V.; Delft University of Technology; Wiggers, Pascal; Delft University of Technology; Broekens, Joost; Delft University of Technology

    2012-01-01

    Negotiation is a complex emotional decision-making process aiming to reach an agreement to exchange goods or services. From an agent technological perspective creating negotiating agents that can support humans with their negotiations is an interesting challenge. Already more than a decade, negotiating agents can outperform human beings (in terms of deal optimality) if the negotiation space is well-understood. However, the inherent semantic problem and the emotional issues involved make that ...

  12. Characterization of a rat salivary sialoglycoprotein complex which agglutinates Streptococcus mutans.

    OpenAIRE

    Brack, C M; Reynolds, E C

    1987-01-01

    Rat saliva agglutinated Streptococcus mutans Ingbritt and NCTC 10449 and Streptococcus sanguis NCTC 7864 but not S. mutans NCTC 10921, GS 5, or LM 7, Streptococcus sobrinus 6715-13 or OMZ 65, or Streptococcus cricetus HS 6, as measured turbidometrically. The specificity of agglutination by rat saliva was the same as that by human saliva. Agglutination was associated with a mucin complex (rat salivary agglutinin complex [rS-A]) of sulfated sialoglycoproteins, with a trace of associated lipid a...

  13. Pericarditis purulenta primaria por Streptococcus pneumoniae, a propósito de un caso clínico Primary purulent pericarditis by Streptococcus pneumoniae. Case-report and literature review

    Directory of Open Access Journals (Sweden)

    ALEJANDRO DONOSO F

    2008-12-01

    Full Text Available Hoy en día la pericarditis purulenta (PP es una patología poco frecuente, pero de pronóstico grave. Comunicamos el caso clínico de un paciente de 3 meses, sano previamente. Consultó por palidez, rechazo alimentario y dificultad respiratoria de pocas horas de evolución. La radiografía de tórax demostró cardiomegalia. Evolucionó hacia shock cardiogénico por taponamiento cardíaco. Recibió inicialmente expansores de volumen y drogas vasoactivas. Antibioterapia con vancomicina y ceftriaxona. Ecocar-diograma objetivó derrame pericárdico extenso, complementado con TAC que descartó foco infeccioso endotoráxico. Se realizó pericardiocentesis y luego ventana pericárdica. Se aisló en hemocultivo Streptococcus pneumoniae, sensible a penicilina. Luego de drenaje quirúrgico y control de infección presentó evolución favorable. No se encontró sitio infeccioso extrapericárdico. Completó tres semanas de tratamiento antibiótico. Estudio inmunológico fue normal. La PP es observada raramente en individuos sanos. La presentación en este caso fue de horas, por un agente inhabitual y de extrema gravedad. Un diagnóstico precoz, en conjunto con un tratamiento médico-quirúrgico es fundamental, como la mejor forma de evitar secuelas.Background: Purulent pericarditis has become a rare clinical entity since the onset of antimicrobial therapy and has a poor outcome in the majority of cases. Case-report: A healthy 3 month-old patient admitted with dyspnea, pallor and anorexia, developing cardiogenic shock due to cardiac tamponade. Chest X-ray showed cardiomegaly. He required mechanical ventilation, volume resuscitation and vasoactive drugs. Echocardiogram showed a large pericardial effusion, CT sean ruled out lung and mediastinal infection. Pericardial drainage was performed and Vancomycin plus Ceftriaxone were initiated, with a positive blood culture for Penicillin-sensitive Streptococcus pneumoniae. The evolution was favourable after surgical drainage and controlling the infection. No extraperdicardial infection was found. He received 3 weeks of antibiotic therapy. Immunological studies were normal. Conclusión: Primary purulent pericarditis is uncommon, so early detection and treatment of this life-threatening condition may lead to a good outcome.

  14. Pericarditis purulenta primaria por Streptococcus pneumoniae, a propósito de un caso clínico / Primary purulent pericarditis by Streptococcus pneumoniae. Case-report and literature review

    Scientific Electronic Library Online (English)

    ALEJANDRO, DONOSO F; FRANCO, DÍAZ R; KATALINA, BERTRÁN S; PABLO, CRUCES R.

    2008-12-01

    Full Text Available Hoy en día la pericarditis purulenta (PP) es una patología poco frecuente, pero de pronóstico grave. Comunicamos el caso clínico de un paciente de 3 meses, sano previamente. Consultó por palidez, rechazo alimentario y dificultad respiratoria de pocas horas de evolución. La radiografía de tórax demos [...] tró cardiomegalia. Evolucionó hacia shock cardiogénico por taponamiento cardíaco. Recibió inicialmente expansores de volumen y drogas vasoactivas. Antibioterapia con vancomicina y ceftriaxona. Ecocar-diograma objetivó derrame pericárdico extenso, complementado con TAC que descartó foco infeccioso endotoráxico. Se realizó pericardiocentesis y luego ventana pericárdica. Se aisló en hemocultivo Streptococcus pneumoniae, sensible a penicilina. Luego de drenaje quirúrgico y control de infección presentó evolución favorable. No se encontró sitio infeccioso extrapericárdico. Completó tres semanas de tratamiento antibiótico. Estudio inmunológico fue normal. La PP es observada raramente en individuos sanos. La presentación en este caso fue de horas, por un agente inhabitual y de extrema gravedad. Un diagnóstico precoz, en conjunto con un tratamiento médico-quirúrgico es fundamental, como la mejor forma de evitar secuelas. Abstract in english Background: Purulent pericarditis has become a rare clinical entity since the onset of antimicrobial therapy and has a poor outcome in the majority of cases. Case-report: A healthy 3 month-old patient admitted with dyspnea, pallor and anorexia, developing cardiogenic shock due to cardiac tamponade. [...] Chest X-ray showed cardiomegaly. He required mechanical ventilation, volume resuscitation and vasoactive drugs. Echocardiogram showed a large pericardial effusion, CT sean ruled out lung and mediastinal infection. Pericardial drainage was performed and Vancomycin plus Ceftriaxone were initiated, with a positive blood culture for Penicillin-sensitive Streptococcus pneumoniae. The evolution was favourable after surgical drainage and controlling the infection. No extraperdicardial infection was found. He received 3 weeks of antibiotic therapy. Immunological studies were normal. Conclusión: Primary purulent pericarditis is uncommon, so early detection and treatment of this life-threatening condition may lead to a good outcome.

  15. Molecular typing of Chinese Streptococcus pyogenes isolates.

    Science.gov (United States)

    You, Yuanhai; Wang, Haibin; Bi, Zhenwang; Walker, Mark; Peng, Xianhui; Hu, Bin; Zhou, Haijian; Song, Yanyan; Tao, Xiaoxia; Kou, Zengqiang; Meng, Fanliang; Zhang, Menghan; Bi, Zhenqiang; Luo, Fengji; Zhang, Jianzhong

    2015-06-01

    Streptococcus pyogenes causes human infections ranging from mild pharyngitis and impetigo to serious diseases including necrotizing fasciitis and streptococcal toxic shock syndrome. The objective of this study was to compare molecular emm typing and pulsed field gel electrophoresis (PFGE) with multiple-locus variable-number tandem-repeat analysis (MLVA) for genotyping of Chinese S. pyogenes isolates. Molecular emm typing and PFGE were performed using standard protocols. Seven variable number tandem repeat (VNTR) loci reported in a previous study were used to genotype 169 S. pyogenes geographically-diverse isolates from China isolated from a variety of disease syndromes. Multiple-locus variable-number tandem-repeat analysis provided greater discrimination between isolates when compared to emm typing and PFGE. Removal of a single VNTR locus (Spy2) reduced the sensitivity by only 0.7%, which suggests that Spy2 was not informative for the isolates screened. The results presented support the use of MLVA as a powerful epidemiological tool for genotyping S. pyogenes clinical isolates. PMID:25843529

  16. Urticaria recurrente asociada a infección por Streptococcus pyogenes / Recurrent urticaria associated with group Streptococcus pyogenes infection

    Scientific Electronic Library Online (English)

    M. P., López Sáez; P., Carrillo Fernández-Paredes; A. J., Huertas Amorós; J. A., Pagán Alemán.

    2013-09-01

    Full Text Available La mayoría de las urticarias crónicas o agudas recidivantes son idiopáticas. Presentamos un caso de urticaria aguda recidivante en una niña de tres años, en la que, tras el estudio realizado, solo se objetivó un valor elevado de anticuerpos antiestreptolisina O (ASLO). La desaparición de la urticari [...] a tras el tratamiento con penicilina G-benzatina intramuscular, junto con la normalización de los ASLO, sugiere que la etiología de esta podría ser las infecciones recurrentes por el Streptococcus pyogenes. Destacar la importancia de incluir en el protocolo diagnóstico de la urticaria la determinación de los ASLO, lo cual permite el diagnóstico y tratamiento precoces de las infecciones por S. pyogenes. Abstract in english We present a case of relapsing acute urticaria in a three years old girl who after the study only showed a high value of ASLO (antistreptolysin O titer). The disappearance of urticaria after intramuscular penicillin G benzathine treatment, together with the ASLO normalization, suggested that the eti [...] ology of this could be recurrent Streptococcal infections. We conclude the importance of including ASLO determination in the diagnostic protocol of urticaria, allowing early diagnosis and treatment of Group A Streptococcus infections.

  17. Streptococcus pneumoniae: sensibilidade a penicilina e moxifloxacina / Streptococcus pneumoniae: susceptibility to penicillin and moxifloxacin

    Scientific Electronic Library Online (English)

    Flávia, Rossi; Maria Renata Gomes, Franco; Heleni Mota de Pina, Rodrigues; Denise, Andreazzi.

    2012-02-01

    Full Text Available OBJETIVO: Determinar a concentração inibitória mínima (CIM) de penicilina parenteral e moxifloxacina contra cepas de Streptococcus pneumoniae isoladas em um centro hospitalar. Métodos: Estudo in vitro prospectivo de 100 isolados de S. pneumoniae coletados de pacientes tratados entre outubro de 2008 [...] e julho de 2010 no complexo do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo, em São Paulo (SP). Os isolados foram obtidos de culturas do trato respiratório e de amostras de sangue não relacionadas a infecções meníngeas e foram testados quanto à suscetibilidade a penicilina e moxifloxacina por E test. As interpretações categóricas de CIM foram baseadas em padrões atualizados. RESULTADOS: Todos os isolados foram suscetíveis a penicilina parenteral (CIM Abstract in english OBJECTIVE: To determine the minimum inhibitory concentrations (MICs) of parenteral penicillin and moxifloxacin against Streptococcus pneumoniae strains isolated at a hospital center. METHODS: In-vitro, prospective study involving 100 S. pneumoniae isolates collected from patients who had been treate [...] d, between October of 2008 and July of 2010, at the Hospital das Clínicas complex of the University of São Paulo School of Medicine, located in the city of São Paulo, Brazil. The isolates were obtained from respiratory tract cultures or blood samples unrelated to meningeal infections, and they were tested for penicillin and moxifloxacin susceptibility by E-test. The MIC category interpretations were based on updated standards. RESULTS: All isolates were fully susceptible to parenteral penicillin (MIC

  18. In Vitro Effect of Zingiber officinale Extract on Growth of Streptococcus mutans and Streptococcus sanguinis.

    Science.gov (United States)

    Azizi, Arash; Aghayan, Shabnam; Zaker, Saeed; Shakeri, Mahdieh; Entezari, Navid; Lawaf, Shirin

    2015-01-01

    Background and Objectives. Tooth decay is an infectious disease of microbial origin. Considering the increasing prevalence of antibiotic resistance due to their overuse and also their side effects, medicinal plants are now considered for use against bacterial infections. This study aimed to assess the effects of different concentrations of Zingiber officinale extract on proliferation of Streptococcus mutans and Streptococcus sanguinis in vitro. Materials and Methods. In this experimental study, serial dilutions of the extract were prepared in two sets of 10 test tubes for each bacterium (total of 20). Standard amounts of bacterial suspension were added; 100? of each tube was cultured on prepared solid agar plates and incubated at 37°C for 24 hours. Serial dilutions of the extract were prepared in another 20 tubes and 100? of each tube was added to blood agar culture medium while being prepared. The mixture was transferred to the plates. The bacteria were inoculated on plates and incubated as described. Results. The minimum inhibitory concentration (MIC) was 0.02?mg/mL for S. mutans and 0.3?mg/mL for S. sanguinis. The minimum bactericidal concentration (MBC) was 0.04?mg for S. mutans and 0.6?mg for S. sanguinis. Conclusion. Zingiber officinale extract has significant antibacterial activity against S. mutans and S. sanguinis cariogenic microorganisms. PMID:26347778

  19. In Vitro Effect of Zingiber officinale Extract on Growth of Streptococcus mutans and Streptococcus sanguinis

    Science.gov (United States)

    Azizi, Arash; Aghayan, Shabnam; Zaker, Saeed; Shakeri, Mahdieh; Entezari, Navid; Lawaf, Shirin

    2015-01-01

    Background and Objectives. Tooth decay is an infectious disease of microbial origin. Considering the increasing prevalence of antibiotic resistance due to their overuse and also their side effects, medicinal plants are now considered for use against bacterial infections. This study aimed to assess the effects of different concentrations of Zingiber officinale extract on proliferation of Streptococcus mutans and Streptococcus sanguinis in vitro. Materials and Methods. In this experimental study, serial dilutions of the extract were prepared in two sets of 10 test tubes for each bacterium (total of 20). Standard amounts of bacterial suspension were added; 100? of each tube was cultured on prepared solid agar plates and incubated at 37°C for 24 hours. Serial dilutions of the extract were prepared in another 20 tubes and 100? of each tube was added to blood agar culture medium while being prepared. The mixture was transferred to the plates. The bacteria were inoculated on plates and incubated as described. Results. The minimum inhibitory concentration (MIC) was 0.02?mg/mL for S. mutans and 0.3?mg/mL for S. sanguinis. The minimum bactericidal concentration (MBC) was 0.04?mg for S. mutans and 0.6?mg for S. sanguinis. Conclusion. Zingiber officinale extract has significant antibacterial activity against S. mutans and S. sanguinis cariogenic microorganisms. PMID:26347778

  20. Caracterización molecular en aislados chilenos de Streptococcus agalactiae / Molecular characterization of Chilean isolates of streptococcus agalactiae

    Scientific Electronic Library Online (English)

    Patricia, Rojo; Pamela, Araya; M Angélica, Martínez T; Juan Carlos, Hormazábal; Aurora, Maldonado; Jorge, Fernández.

    2008-05-01

    Full Text Available [...] Abstract in english Streptococcus agalactiae is the main causing organism of invasive infections such as sepsis and meningitis in the newborn. Aim: To perform a genotype characterization of Streptococcus agalactiae strains coming form invasive infections of newborns and colonized pregnant women. Material and methods: A [...] group of 58 strains not related epidemiologically isolated from colonized pregnant women and invasive infections in newborns, were studied. Pulsed field electrophoresis (PFGE) and polymerase chain reaction amplification of hylB and IS 1548 genes, as possible virulence markers, were performed. Results: Among the studied strains, 37 genetic subtypes were observed. There were nine groups of identical PFGE patterns. Three corresponded to serotype la and six to serotype III. An erythromycin and clindamycin resistant clone was identified in three colonized women and a newborn with sepsis, which were not epidemiologically related. The hylB gene was equally present in cases of neonatal meningitis or colonized pregnant women. Conclusions: There was a great degree of polymorphism among the studied strains. The ample presence of hylB gene and the absence of the insertion element IS1548 in the hylB gene in invasive and colonizing strains, indicates that both groups of strains are potentially pathogenic

  1. Group B streptococcal neonatal infections in Rio Grande do Sul, Brazil Infecção neonatal por Streptococcus do grupo B no Rio Grande do Sul, Brasil

    Directory of Open Access Journals (Sweden)

    Ernani MIURA

    2001-10-01

    Full Text Available Group B Streptococcus is the most common pathogen found in neonatal sepsis in North America. OBJECTIVES: We describe 15 cases of neonatal infections by Group B Streptococcus (Streptococcus agalactiae at a Neonatal Intensive Care Unit of a public and teaching hospital. METHODS: We conducted a study at Hospital de Clínicas de Porto Alegre, from January 1st, 1996 to June 30, 1999. Diagnosis of neonatal infection was established according to the findings of Group B Streptococcus in blood culture associated with alterations resembling sepsis on the basis of clinical picture and laboratory findings. RESULTS: Fifteen cases of neonatal infections by Group B Streptococcus were detected. Eleven cases consisted of early-onset sepsis, 2 cases of occult bacteremia and 2 cases of late-onset sepsis. Eight cases had septic shock (53%, 8 cases had pneumonia (53%, and 4 cases had meningitis (27%. Fourteen cases were diagnosed from a positive blood culture, and 1 case from evidence of these bacteria in pulmonary anatomopathological examination. Thirteen cases (87% were diagnosed before 72 hours of life. We had 3 deaths (20%, and 3 cases of meningitis developing neurological deficits. CONCLUSIONS: Streptococcus Group B is one of the most important pathogens in the etiology of early-onset neonatal sepsis at our hospital, with high mortality and morbidity. However, we do not know the incidence of GBS neonatal infections at other hospitals. More data are needed to establish a basis for trials of different strategies to reduce these infections.FUNDAMENTOS: Streptococcus do grupo B é o principal agente etiológico responsável pela sepse neonatal na América do Norte. OBJETIVOS: Relatar 15 casos de infecção neonatal por Streptococcus do grupo B (Streptococus agalactiae ocorridos na Unidade de Tratamento Intensivo Neonatal de um hospital público e universitário. MÉTODO: O estudo foi realizado no Hospital de Clínicas de Porto Alegre no período de 1º de janeiro de 1996 a 30 de junho de 1999. O diagnóstico de infecção neonatal foi feito a partir do isolamento e identificação de Streptococcus do grupo B em hemocultura combinado com alterações clínicas e laboratoriais sugestivas de sepse. RESULTADOS: Foram detectados quinze casos de infecção neonatal por Streptococcus do grupo B, sendo onze casos de sepse de origem precoce, dois casos de bacteremia oculta e dois casos de sepse de origem tardia. Oito casos tiveram choque séptico (53%, oito casos com pneumonia (53% e quatro casos com meningite (27%. Quatorze casos foram diagnosticados a partir da hemocultura e um caso através da presença desta bactéria no exame anátomo-patológico do pulmão. Treze casos (87% foram diagnosticados antes de três dias de vida. Ocorreram três óbitos (20% e três pacientes com meningite ficaram com seqüelas neurológicas. CONCLUSÃO: O Streptococcus do Grupo B é uma das bactérias mais importantes na etiologia da sepse neonatal de início precoce em nosso hospital com elevada mortalidade e também com elevada morbidade. Entretanto, não se conhece sua incidência em outros hospitais. São necesssários outros estudos para determinar seu papel na sepse neonatal e assim estabelecer diferentes estratégias para sua redução.

  2. Group B streptococcal neonatal infections in Rio Grande do Sul, Brazil / Infecção neonatal por Streptococcus do grupo B no Rio Grande do Sul, Brasil

    Scientific Electronic Library Online (English)

    Ernani, MIURA; Maria Cristina, MARTIN.

    2001-10-01

    Full Text Available FUNDAMENTOS: Streptococcus do grupo B é o principal agente etiológico responsável pela sepse neonatal na América do Norte. OBJETIVOS: Relatar 15 casos de infecção neonatal por Streptococcus do grupo B (Streptococus agalactiae) ocorridos na Unidade de Tratamento Intensivo Neonatal de um hospital públ [...] ico e universitário. MÉTODO: O estudo foi realizado no Hospital de Clínicas de Porto Alegre no período de 1º de janeiro de 1996 a 30 de junho de 1999. O diagnóstico de infecção neonatal foi feito a partir do isolamento e identificação de Streptococcus do grupo B em hemocultura combinado com alterações clínicas e laboratoriais sugestivas de sepse. RESULTADOS: Foram detectados quinze casos de infecção neonatal por Streptococcus do grupo B, sendo onze casos de sepse de origem precoce, dois casos de bacteremia oculta e dois casos de sepse de origem tardia. Oito casos tiveram choque séptico (53%), oito casos com pneumonia (53%) e quatro casos com meningite (27%). Quatorze casos foram diagnosticados a partir da hemocultura e um caso através da presença desta bactéria no exame anátomo-patológico do pulmão. Treze casos (87%) foram diagnosticados antes de três dias de vida. Ocorreram três óbitos (20%) e três pacientes com meningite ficaram com seqüelas neurológicas. CONCLUSÃO: O Streptococcus do Grupo B é uma das bactérias mais importantes na etiologia da sepse neonatal de início precoce em nosso hospital com elevada mortalidade e também com elevada morbidade. Entretanto, não se conhece sua incidência em outros hospitais. São necesssários outros estudos para determinar seu papel na sepse neonatal e assim estabelecer diferentes estratégias para sua redução. Abstract in english Group B Streptococcus is the most common pathogen found in neonatal sepsis in North America. OBJECTIVES: We describe 15 cases of neonatal infections by Group B Streptococcus (Streptococcus agalactiae) at a Neonatal Intensive Care Unit of a public and teaching hospital. METHODS: We conducted a study [...] at Hospital de Clínicas de Porto Alegre, from January 1st, 1996 to June 30, 1999. Diagnosis of neonatal infection was established according to the findings of Group B Streptococcus in blood culture associated with alterations resembling sepsis on the basis of clinical picture and laboratory findings. RESULTS: Fifteen cases of neonatal infections by Group B Streptococcus were detected. Eleven cases consisted of early-onset sepsis, 2 cases of occult bacteremia and 2 cases of late-onset sepsis. Eight cases had septic shock (53%), 8 cases had pneumonia (53%), and 4 cases had meningitis (27%). Fourteen cases were diagnosed from a positive blood culture, and 1 case from evidence of these bacteria in pulmonary anatomopathological examination. Thirteen cases (87%) were diagnosed before 72 hours of life. We had 3 deaths (20%), and 3 cases of meningitis developing neurological deficits. CONCLUSIONS: Streptococcus Group B is one of the most important pathogens in the etiology of early-onset neonatal sepsis at our hospital, with high mortality and morbidity. However, we do not know the incidence of GBS neonatal infections at other hospitals. More data are needed to establish a basis for trials of different strategies to reduce these infections.

  3. Gene cloning and characterization of MdeA, a novel multidrug efflux pump in Streptococcus mutans.

    Science.gov (United States)

    Kim, Do Kyun; Kim, Kyoung Hoon; Cho, Eun Ji; Joo, Seoung-Je; Chung, Jung-Min; Son, Byoung Yil; Yum, Jong Hwa; Kim, Young-Man; Kwon, Hyun-Ju; Kim, Byung-Woo; Kim, Tae Hoon; Lee, Eun-Woo

    2013-03-01

    Multidrug resistance, especially multidrug efflux mechanisms that extrude structurally unrelated cytotoxic compounds from the cell by multidrug transporters, is a serious problem and one of the main reasons for the failure of therapeutic treatment of infections by pathogenic microorganisms as well as of cancer cells. Streptococcus mutans is considered one of the primary causative agents of dental caries and periodontal disease, which comprise the most common oral diseases. A fragment of chromosomal DNA from S. mutans KCTC3065 was cloned using Escherichia coli KAM32 as host cells lacking major multidrug efflux pumps. Although E. coli KAM32 cells were very sensitive to many antimicrobial agents, the transformed cells harboring a recombinant plasmid became resistant to several structurally unrelated antimicrobial agents such as tetracycline, kanamycin, rhodamin 6G, ampicillin, acriflavine, ethidium bromide, and tetraphenylphosphonium chloride. This suggested that the cloned DNA fragment carries a gene encoding a multidrug efflux pump. Among 49 of the multidrug-resistant transformants, we report the functional gene cloning and characterization of the function of one multidrug efflux pump, namely MdeA from S. mutans, which was expressed in E. coli KAM32. Judging from the structural and biochemical properties, we concluded that MdeA is the first cloned and characterized multidrug efflux pump using the proton motive force as the energy for efflux drugs. PMID:23462018

  4. Lysogenic Transfer of Group A Streptococcus Superantigen Gene among Streptococci

    OpenAIRE

    Vojtek, Ivo; Pirzada, Zaid A; Henriques-Normark, Birgitta; Mastny, Markus; Janapatla, Rajendra P.; Charpentier, Emmanuelle

    2008-01-01

    A group A Streptococcus(GAS) isolate,serotypeM12,recovered from a patient with streptococcal toxic shock syndrome was analyzed for superantigen-carrying prophages, revealing 149, which encodes superantigen SSA. Sequence analysis of the att-L proximal region of 149 showed that the phage had a mosaic nature. Remarkably, we successfully obtained lysogenic conversion of GAS clinical isolates of various M serotypes (M1, M3, M5, M12, M19, M28, and M94), as well as of group C Streptococcus equisimil...

  5. Immunoasssay Chromatographic Antigen Test for Rapid Diagnosis of Group A Beta Hemolytic Streptococcus Pharyngitis in Children: A Cross/ Sectional Study

    Directory of Open Access Journals (Sweden)

    S Noorbakhsh

    2011-06-01

    Full Text Available Background and Objective: Group A beta-hemolytic streptococcus (GABHS is an important pharyngotonsillitis etiologic agent in children. The objective of this study was diagnosis of streptococcal pharyngitis based on rapid antigen detection test and conventional pharyngeal culture.Materials and Methods: The rapid GABHS antigen detection test was compared to culture on blood agar, the gold standard for the diagnosis of this etiologic agent.Results: Streptococcal antigen was detected in pharyngeal specimens of 34.5% of cases by rapid strip test. We detected group A Streptococcus in 17.2% of pharyngeal culture. There was no agreement between two methods ( PV < 0.1. The negative pharyngeal culture results are probably due to antibiotic usage in 43.2 % of patients. Positive rapid test results in pharyngeal swab was age dependent ( P < 0.05. There was good correlation between observing the "petechia in pharynx of patients" and positive rapid test in pharyngeal swab (P < 0.004. Throat culture results were relatated to previous antibiotic usage ( P < 0.03.Conclusion: The rapid test in pharyngeal swab is helpful for rapid diagnosis and treatment of GABHS pharyngitis. Diagnosis of GABHS pharyngitis based on soley clinical findings is misleading in the majority of cases. Petechia observed in pharynx of the cases was highly predictive of streptococcal pharyngitis.

  6. Effect of irradiation on the streptococcus mutans

    Energy Technology Data Exchange (ETDEWEB)

    Ahn, Ki Dong; Kim, Gyu Tae; Choi, Yong Suk; Hwang, Eui Hwan [Kyung Hee Univ., Seoul (Korea, Republic of)

    2007-03-15

    To observe direct effect of irradiation on cariogenic Streptococcus mutans. S. mutans GS5 was exposed to irradiation with a single absorbed dose of 10, 20, 30, and 40 Gy. Viability and changes in antibiotic sensitivity, morphology, transcription of virulence factors, and protein profile of bacterium after irradiation were examined by pour plate, disc diffusion method, Transmission electron microscopy. RT-PCR, and SDS-PAGE, respectively. After irradiation with 10 and 20 Gy, viability of S. mutans was reduced. Further increase in irradiation dose, however, did not affect the viability of the remaining cells of S. mutans. Irradiated S. mutans was found to have become sensitive to antibiotics. In particular, the bacterium irradiated with 40 Gy increased its susceptibility to cefotaxime, penicillin, and tetracycline. Under the transmission electron microscope, number of morphologically abnormal cells was increased as the irradiation dose was increased. S. mutans irradiated with 10 Gy revealed a change in the cell wall and cell membrane. As irradiation dose was increased. a higher number of cells showed thickened cell wall and cell membrane and lysis, and appearance of ghost cells was noticeable. In RT-PCR, no difference was detected in expression of gtfB and spaP between cells with and without irradiation of 40 Gy. In SDS-PAGE, proteins with higher molecular masses were gradually diminished as irradiation dose was increased. These results suggest that irradiation affects the cell integrity of S. mutans, as observed by SDS-PAGE, and as manifested by the change in cell morphology, antibiotic sensitivity, and eventually viability of the bacterium.

  7. Functional amyloid formation by Streptococcus mutans.

    Science.gov (United States)

    Oli, M W; Otoo, H N; Crowley, P J; Heim, K P; Nascimento, M M; Ramsook, C B; Lipke, P N; Brady, L J

    2012-12-01

    Dental caries is a common infectious disease associated with acidogenic and aciduric bacteria, including Streptococcus mutans. Organisms that cause cavities form recalcitrant biofilms, generate acids from dietary sugars and tolerate acid end products. It has recently been recognized that micro-organisms can produce functional amyloids that are integral to biofilm development. We now show that the S. mutans cell-surface-localized adhesin P1 (antigen I/II, PAc) is an amyloid-forming protein. This conclusion is based on the defining properties of amyloids, including binding by the amyloidophilic dyes Congo red (CR) and Thioflavin T (ThT), visualization of amyloid fibres by transmission electron microscopy and the green birefringent properties of CR-stained protein aggregates when viewed under cross-polarized light. We provide evidence that amyloid is present in human dental plaque and is produced by both laboratory strains and clinical isolates of S. mutans. We provide further evidence that amyloid formation is not limited to P1, since bacterial colonies without this adhesin demonstrate residual green birefringence. However, S. mutans lacking sortase, the transpeptidase enzyme that mediates the covalent linkage of its substrates to the cell-wall peptidoglycan, including P1 and five other proteins, is not birefringent when stained with CR and does not form biofilms. Biofilm formation is inhibited when S. mutans is cultured in the presence of known inhibitors of amyloid fibrillization, including CR, Thioflavin S and epigallocatechin-3-gallate, which also inhibited ThT uptake by S. mutans extracellular proteins. Taken together, these results indicate that S. mutans is an amyloid-forming organism and suggest that amyloidogenesis contributes to biofilm formation by this oral microbe. PMID:23082034

  8. Group B Streptococcus induces apoptosis in macrophages.

    Science.gov (United States)

    Fettucciari, K; Rosati, E; Scaringi, L; Cornacchione, P; Migliorati, G; Sabatini, R; Fetriconi, I; Rossi, R; Marconi, P

    2000-10-01

    Group B Streptococcus (GBS) is a pathogen that has developed some strategies to resist host immune defenses. Because phagocytic killing is an important pathogenetic mechanism for bacteria, we investigated whether GBS induces apoptosis in murine macrophages. GBS type III strain COH31 r/s (GBS-III) first causes a defect in cell membrane permeability, then at 24 h, apoptosis. Apoptosis was confirmed by several techniques based on morphological changes and DNA fragmentation. Cytochalasin D does not affect apoptosis, suggesting that GBS-III needs not be within the macrophage cytoplasm to promote apoptosis. Inhibition of host protein synthesis prevents apoptosis, whereas inhibition of caspase-1 or -3, does not. Therefore, GBS can trigger an apoptotic pathway independent of caspase-1 and -3, but dependent on protein synthesis. Inhibition of apoptosis by EGTA and PMA, and enhancement of apoptosis by calphostin C and GF109203X suggests that an increase in the cytosolic calcium level and protein kinase C activity status are important in GBS-induced apoptosis. Neither alteration of plasma membrane permeability nor apoptosis were induced by GBS grown in conditions impeding hemolysin expression or when we used dipalmitoylphosphatidylcholine, which inhibited GBS beta-hemolytic activity, suggesting that GBS beta-hemolysin could be involved in apoptosis. beta-Hemolysin, by causing membrane permeability defects, could allow calcium influx, which initiates macrophage apoptosis. GBS also induces apoptosis in human monocytes but not in tumor lines demonstrating the specificity of its activity. This study suggests that induction of macrophage apoptosis by GBS is a novel strategy to overcome host immune defenses. PMID:11034400

  9. Transduction of the Streptococcus pyogenes bacteriophage ?m46.1, carrying resistance genes mef(A) and tet(O), to other Streptococcus species

    OpenAIRE

    Giovanetti, Eleonora; Brenciani, Andrea; Morroni, Gianluca; Tiberi, Erika; Pasquaroli, Sonia; Mingoia, Marina; Pietro E. Varaldo

    2015-01-01

    ?m46.1 – Streptococcus pyogenes bacteriophage carrying mef(A) and tet(O), respectively, encoding resistance to macrolides (M phenotype) and tetracycline – is widespread in S. pyogenes but has not been reported outside this species. ?m46.1 is transferable in vitro among S. pyogenes isolates, but no information is available about its transferability to other Streptococcus species. We thus investigated ?m46.1 for its ability to be transduced in vitro to recipients of different Streptococcus spec...

  10. Isolamento de Streptococcus pyogenes em indivíduos com faringoamigdalite e teste de susceptibilidade a antimicrobianos / Isolation of Streptococcus pyogenes in individuals with pharyngotonsillitis and antimicrobial susceptibility testing

    Scientific Electronic Library Online (English)

    Rozana, Scalabrin; Gisele D., Buss; Kelly Cristina S., Iamaguchi; Celso Luiz, Cardoso; Lourdes B., Garcia.

    2003-12-01

    Full Text Available OBJETIVO: Investigamos a ocorrência de Streptococcus pyogenes em indivíduos com faringoamigdalite que espontaneamente procuraram atendimento em farmácias e unidades de saúde. FORMA DE ESTUDO: Coorte longitudinal. MATERIAL E MÉTODOS: Com auxílio de "swab" e abaixador de língua foram coletadas amostra [...] s da orofaringe de 58 indivíduos, as quais foram semeadas por técnica de esgotamento em placas contendo ágar sangue. No momento da coleta, nenhum dos indivíduos estava sob tratamento com antibióticos. A identificação do S. pyogenes foi feita presuntivamente pelo teste de sensibilidade a bacitracina e confirmada pela grupagem sorológica através da extração do antígeno grupo-específico. RESULTADOS: Das 58 amostras de orofaringe analisadas, 32 (55,2%) foram provenientes de indivíduos atendidos em farmácias e 26 (44,8%) foram obtidas daqueles que procuraram as unidades de saúde. Um total de 15 (25,9%) amostras apresentou cultura positiva para S. pyogenes, sendo a maioria dos isolamentos (9/15, 60%) proveniente de indivíduos atendidos em farmácia. Streptococcus pyogenes foi isolado em 33,3% (11/33) dos indivíduos com idade entre zero e 15 anos e em 16% (4/25) daqueles com idade acima de 15 anos. As 15 cepas isoladas foram sensíveis a todos os antimicrobianos testados. CONCLUSÃO: Os resultados do presente estudo enfatizam a importância do diagnóstico bacteriológico no tratamento adequado da faringoamigdalite estreptocócica que permite a prevenção das complicações supurativas ou não supurativas e a erradicação do microrganismo da orofaringe. Abstract in english AIM: We investigate the occurrence of Streptococcus pyogenes in individuals with pharyngotonsillitis that spontaneously sought attendance in drugstores or in health units. STUDY DESIGN: Longitudinal cohorte. MATERIAL AND METHOD: Samples from oropharynx of 58 individuals were collected with swab and [...] tongue depressor and inoculated on sheep blood agar plates. At the moment the samples were collected, none of the individuals was under treatment with antibiotics. The presumptive identification of S. pyogenes was made by the susceptibility test to bacitracin and confirmed by the serological grouping through the extraction of the group-specific carbohydrate "C" antigen. RESULTS: From the 58 samples of oropharynx analyzed, 32 (55.2%) were from individuals assisted in drugstores and 26 (44.8%) were obtained from those that sought health units. A total of 15 (25.9%) samples presented positive culture for S. pyogenes, being most of the strains (9/15, 60%) coming from individuals assisted in drugstores. Streptococcus pyogenes was isolated in 33.3% (11/33) of the individuals from zero to 15 years of age and in 16% (4/25) of those over 15. The strains were susceptible to all the antimicrobial agents tested. CONCLUSION: The results of the present study emphasize the importance of the bacteriological diagnosis in the proper treatment for the streptococcal pharyngotonsillitis that determine the prevention of the supurative or non supurative complications and the eradication of the microorganism of the oropharynx.

  11. Effects of N-acetylglucosamine on carbohydrate fermentation by Streptococcus mutans NCTC 10449 and Streptococcus sobrinus SL-1.

    OpenAIRE

    Homer, K A; Patel, R.; Beighton, D

    1993-01-01

    We have investigated the ability of two species of streptococci isolated from the human oral cavity (Streptococcus mutans NCTC 10449 and Streptococcus sobrinus SL-1) to metabolize N-acetylglucosamine (GlcNAc), a naturally occurring amino sugar present in saliva and human glycoproteins, when provided as the sole fermentable carbohydrate and determined the effects of the presence of GlcNAc on the fermentation of other carbohydrates. S. mutans used GlcNAc at concentrations of up to 10 mM to incr...

  12. Purification and properties of pyruvate kinase from Streptococcus sanguis and activator specificity of pyruvate kinase from oral streptococci.

    OpenAIRE

    Abbe, K; Takahashi, S.; T. Yamada

    1983-01-01

    It was found that pyruvate kinases with two different regulatory characteristics were distributed among oral streptococci. The pyruvate kinases of Streptococcus mutans, Streptococcus salivarius, and Streptococcus bovis were activated by glucose 6-phosphate, whereas the enzymes of both Streptococcus sanguis and Streptococcus mitis were activated by fructose 1,6-bisphosphate. Pyruvate kinase (EC 2.7.1.40) from S. sanguis NCTC 10904 was purified, giving a single band on sodium dodecyl sulfate-po...

  13. Infecciones invasoras por Streptococcus b hemolítico Grupo A / Grupo Invasive infections by group a streptococcus

    Scientific Electronic Library Online (English)

    Claudia, Alarcón O; Mary Carmen, Ordenes P; Marisol, Denegri M; Jorge, Zúñiga.

    2006-10-01

    Full Text Available Desde los años ochenta ha habido un resurgimiento de infecciones severas por Streptococcus b hemolítico Grupo A (SBHGA). Objetivo: Evaluar en nuestro medio el comportamiento clínico y los factores predisponentes en infecciones invasoras por SBHGA. Material y Métodos: Se analizaron antecedentes clíni [...] cos de 37 fichas de niños con cultivo positivo al SBHGA hospitalizados en el Servicio de Pediatría y Cirugía Infantil del Hospital Dr. Félix Bulnes Cerda entre marzo de 1995 y enero de 2005. Resultados: 81% fueron pacientes eutróficos sin patología asociada. Destacan como factores condicionantes: quemadura (30%), varicela (19%) y traumatismo (16%). La sintomatología más frecuente fue fiebre (84%) y signos inflamatorios locales (40%). Los cuadros clínicos fueron: infección de tejido blando (32%), bacteremia sin focalización (30%), osteoartritis (10,8%), pleuroneumonía (10,8%), shock tóxico (8,1%) y fasceitis necrotizante (5,4%). Tres pacientes fallecieron. Conclusión: Las infecciones invasoras por SBHGA afectan mayoritariamente a niños sanos cuyo principal factor predisponente es una puerta cutánea, y puede ser fatal Abstract in english Since 1980 there has been a resurgence of severe infections by Group A Streptococcus (GAS). Objective: To evaluate in our hospital the clinical behaviour and predisposing factors for GAS infections. Methods: Clinical information from 37 charts of children with GAS positive cultures hospitalized in F [...] élix Bulnes Cerda Hospital were analyzed between March 1995 and January 2005. Results: 81% healthy children with predisposing factors: burns (30%), varicella (19%) and trauma (16%). The main symptoms were fever (84%) and local inflammatory signs (40%). The clinical manifestations include soft tissue infections (32%), bacteremia (30%), osteoarthritis (10,8%), empyema (10,8%), toxic shock (8,1%) and necrotizing fasciitis (5,4%). Three patients died. Conclusion: Invasive GAS mainly affects healthy children with skin port of entry and may cause death

  14. Serotipos y susceptibilidad antimicrobiana de Streptococcus agalactiae / Serotypes and antimicrobial susceptibility of Streptococcus agalactiae

    Scientific Electronic Library Online (English)

    María Angélica, Martínez T; Alfredo, Ovalle S; Claudia, Durán T; Iván, Reid S; Gabriela, Urriola J; Beatriz, Garay G; Marcela, Cifuentes D.

    2004-05-01

    Full Text Available [...] Abstract in english Background : Streptococcus agalactiae or group B streptococcus, GBS, is the leading cause of neonatal and maternal infections and an opportunistic pathogen in adults with underlying disease. In the last decade, a dramatic increase in the resistance of this microorganism to erythromycin and clindamyc [...] in has been observed. Aim: To determine the serotype distribution and antimicrobial susceptibility of isolates of S agalactiae collected from infections and colonization and to assess the genetic mechanisms of macrolide and clindamycin resistance. Material and methods: A total of 100 GBS isolates were collected between 1998 and 2002, in Santiago, Chile. They were isolated from the amniotic fluid from patients with premature rupture of membranes (7 isolates), blood from neonatal sepsis (10 isolates), neonate colonizations (2 strains), skin and soft tissue infections (7 isolates), urinary tract infections (5 isolates), genital infections (3 isolates), articular fluid (one isolate), and 65 strains were recovered from vaginal colonization55. Results: Serotypes Ia, II and III were the predominant serotypes identified in our study, accounting for 90 (90%) of the strains. Five isolates belonged to serotypes Ib (5%) and two (2%) to serotype V respectively; no strains belonging to serotype IV were found. All strains were susceptible to penicillin G, ampicillin and cefotaxime, and four isolates (4%) were resistant to both erythromycin (MIC >64 µg/ml) and clindamycin (MIC >64 µg/ml). The strains had a constitutive macrolide-lincosamide-streptogramin (cMLSB) resistance phenotype and the erm(A) gene was present in the four isolates. Conclusions: Serotypes Ia, II and III were the predominant serotypes in this study. All strains were susceptible to penicillin G, ampicillin and cefotaxime, and four (4%) strains were resistant to both erythromycin and clindamycin. The cMLSB resistance phenotype, and the erm(A) gene was detected in resistant strains (Rev Méd Chile 2004; 132: 549-55).

  15. Serotipos y susceptibilidad antimicrobiana de Streptococcus agalactiae Serotypes and antimicrobial susceptibility of Streptococcus agalactiae

    Directory of Open Access Journals (Sweden)

    María Angélica Martínez T

    2004-05-01

    Full Text Available Background : Streptococcus agalactiae or group B streptococcus, GBS, is the leading cause of neonatal and maternal infections and an opportunistic pathogen in adults with underlying disease. In the last decade, a dramatic increase in the resistance of this microorganism to erythromycin and clindamycin has been observed. Aim: To determine the serotype distribution and antimicrobial susceptibility of isolates of S agalactiae collected from infections and colonization and to assess the genetic mechanisms of macrolide and clindamycin resistance. Material and methods: A total of 100 GBS isolates were collected between 1998 and 2002, in Santiago, Chile. They were isolated from the amniotic fluid from patients with premature rupture of membranes (7 isolates, blood from neonatal sepsis (10 isolates, neonate colonizations (2 strains, skin and soft tissue infections (7 isolates, urinary tract infections (5 isolates, genital infections (3 isolates, articular fluid (one isolate, and 65 strains were recovered from vaginal colonization55. Results: Serotypes Ia, II and III were the predominant serotypes identified in our study, accounting for 90 (90% of the strains. Five isolates belonged to serotypes Ib (5% and two (2% to serotype V respectively; no strains belonging to serotype IV were found. All strains were susceptible to penicillin G, ampicillin and cefotaxime, and four isolates (4% were resistant to both erythromycin (MIC >64 µg/ml and clindamycin (MIC >64 µg/ml. The strains had a constitutive macrolide-lincosamide-streptogramin (cMLSB resistance phenotype and the erm(A gene was present in the four isolates. Conclusions: Serotypes Ia, II and III were the predominant serotypes in this study. All strains were susceptible to penicillin G, ampicillin and cefotaxime, and four (4% strains were resistant to both erythromycin and clindamycin. The cMLSB resistance phenotype, and the erm(A gene was detected in resistant strains (Rev Méd Chile 2004; 132: 549-55.

  16. Biological Agents

    Science.gov (United States)

    ... New Biological agents include bacteria, viruses, fungi, other microorganisms and their associated toxins. They have the ability ... It is often the result of poorly maintained air conditioning cooling towers and potable water systems. Mold . ...

  17. Vasoactive Agents

    OpenAIRE

    Goranovic, Tanja; Bradic, Nikola; Husedzinovic, Ino

    2006-01-01

    This article is a short review of vasoactive drugs which are in use in todays clinical practice. In the past century, development of vasoactive drugs went through several phases. All of these drugs are today divided into several groups, depending on their place of action, pharmacological pathways and/or effects on target organ or organ system. Hence, many different agents are today in clinical practice, we have shown comparison between them. These agents provide new directions in the treatmen...

  18. Screening Protocols for Group B Streptococcus: Are Transport Media Appropriate?

    OpenAIRE

    Nicolette Teese; Daneeta Henessey; Christopher Pearce; Nigel Kelly; Suzanne Garland

    2003-01-01

    Objective: To evaluate group B streptococcus (GBS) detection in an in vitro setting, using a low and controlled inoculum from swabs directly inoculated into a selective medium, as compared to delayed inoculation following a period in a commercial Amies transport medium with charcoal (Venturi Transystem™ Copan, Italy).

  19. Latex Assay for Serotyping of Group B Streptococcus Isolates

    OpenAIRE

    Slotved, H.-C.; Elliott, J.; Thompson, T.; Konradsen, H B

    2003-01-01

    We developed a group B streptococcus (GBS) latex serotyping kit that reduces the numbers of GBS nontypeable isolates by nearly 50%. A total of 232 isolates were tested, and 203 isolates were serotyped by the GBS latex test, while the capillary precipitation test serotyped 184 isolates.

  20. Amoeba Host Model for Evaluation of Streptococcus suis Virulence ?

    OpenAIRE

    Bonifait, Laetitia; Charette, Steve J; Filion, Geneviève; Gottschalk, Marcelo; Grenier, Daniel

    2011-01-01

    The Gram-positive bacterium Streptococcus suis is a major swine pathogen worldwide that causes meningitis, septicemia, and endocarditis. In this study, we demonstrate that the amoeba Dictyostelium discoideum can be a relevant alternative system to study the virulence of S. suis.

  1. Methods for predicting susceptibility of Streptococcus pneumoniae to cefixime.

    OpenAIRE

    Barry, A L; Fuchs, P C

    1995-01-01

    Among 698 Streptococcus pneumoniae isolates, 475 were penicillin susceptible and > 99% of those were susceptible to 0.5 microgram of cefixime per ml; other pneumococci were tentatively assumed to be resistant to cefixime. A 1-microgram oxacillin disk was more reliable than a 5-micrograms cefixime disk for predicting susceptibility to cefixime.

  2. Bartholin's Gland Abscesses Caused by Streptococcus pneumoniae in a Primigravida

    OpenAIRE

    Saeed, Nermin Kamal; Zainab A. Al-Jufairi

    2013-01-01

    Bartholin gland cysts and abscesses are common problems in females during their reproductive time. Majority of Bartholin's gland abscesses described are of polymicrobial nature, but not necessarily involves opportunistic microbes that colonize the perineal region. In this report, we describe a case of Bartholin's abscess caused by Streptococcus pneumoniae in a 25-year-old non-diabetic primigravida.

  3. Streptococcus Gallolyticus Bacteraemia associated with colonic adenomatous polyps

    Scientific Electronic Library Online (English)

    A., Murinello; P., Mendonça; C., Ho; P., Tavares; H., Peres; R. Rio, Tinto; A., Morbey; C., Campos; A., Lázaro; A., Milheiro; M. J., Arias; J., Oliveira; S., Braz.

    2006-05-01

    Full Text Available A bacteriémia por Streptococcus gallolyticus associa-se frequentemente ao carcinoma colorrectal, tornando obrigatória a colonoscopia nestas situações. A endocardite bacteriana e a artrite séptica são também comuns neste tipo de bacteriémias. Tem sido levantada a hipótese das bactérias intestinais po [...] derem ter um papel promotor de hiperproliferação celular aberrante em lesões cólicas pré-neoplásicas, aparentemente devido a processos inflamatórios crónicos e produção de metabolitos carcinogénicos. Os autores apresentam o caso dum doente com vários pólipos adenomatosos tubulares do cólon direito, em dois dos quais se demonstrou uma área de displasia de alto grau adjacente a zona de colite infecciosa bacteriana, associados a quadro clínico de infecção sistémica por Streptococcus gallolyticus e artrite do tornozelo. Abstract in english Bacteraemia due to Streptococcus gallolyticus is frequently associated with colorectal carcinoma, making evaluation of the gastrointestinal tract by colonoscopy obligatory in such cases. Bacterial endocarditis and purulent arthritis are also common in patients with these bacteraemias. Intestinal bac [...] teria could behave as promoters of aberrant hyperproliferative behaviour in preneoplastic colorectal lesions, apparently due to chronic inflammatory processes and production of carcinogenic metabolites. The authors treated a patient with several tubular adenomatous polyps of the right colon, two of which showed areas of high-grade dysplasia adjacent to areas of infectious bacterial colitis associated with Streptococcus gallolyticus bacteraemia and unilateral ankle arthritis.

  4. Plasmid mediated enhancement of uv resistance in Streptococcus faecalis

    Energy Technology Data Exchange (ETDEWEB)

    Miehl, R.; Miller, M.; Yasbin, R.E.

    1980-01-01

    A 38.5-Mdal plasmid of Streptococcus faecalis subdp. zymogenes has been shown to enhance survival following uv irradiation. In addition, the presence of this plasmid increases the mutation frequencies following uv irradiation and enhanced W-reactivation. The data presented indicate that S. faecalis has an inducible error-prone repair system and that the plasmid enhances these repair functions.

  5. Transformation of Streptococcus lactis Protoplasts by Plasmid DNA †

    OpenAIRE

    Kondo, Jeffery K.; McKay, Larry L.

    1982-01-01

    Polyethylene glycol-treated protoplasts prepared from Streptococcus lactis LM3302, a lactose-negative (Lac?) derivative of S. lactis ML3, were transformed to lactose-fermenting ability by a transductionally shortened plasmid (pLM2103) coding for lactose utilization.

  6. Streptococcus Gallolyticus Bacteraemia associated with colonic adenomatous polyps

    Directory of Open Access Journals (Sweden)

    A. Murinello

    2006-05-01

    Full Text Available Bacteraemia due to Streptococcus gallolyticus is frequently associated with colorectal carcinoma, making evaluation of the gastrointestinal tract by colonoscopy obligatory in such cases. Bacterial endocarditis and purulent arthritis are also common in patients with these bacteraemias. Intestinal bacteria could behave as promoters of aberrant hyperproliferative behaviour in preneoplastic colorectal lesions, apparently due to chronic inflammatory processes and production of carcinogenic metabolites. The authors treated a patient with several tubular adenomatous polyps of the right colon, two of which showed areas of high-grade dysplasia adjacent to areas of infectious bacterial colitis associated with Streptococcus gallolyticus bacteraemia and unilateral ankle arthritis.A bacteriémia por Streptococcus gallolyticus associa-se frequentemente ao carcinoma colorrectal, tornando obrigatória a colonoscopia nestas situações. A endocardite bacteriana e a artrite séptica são também comuns neste tipo de bacteriémias. Tem sido levantada a hipótese das bactérias intestinais poderem ter um papel promotor de hiperproliferação celular aberrante em lesões cólicas pré-neoplásicas, aparentemente devido a processos inflamatórios crónicos e produção de metabolitos carcinogénicos. Os autores apresentam o caso dum doente com vários pólipos adenomatosos tubulares do cólon direito, em dois dos quais se demonstrou uma área de displasia de alto grau adjacente a zona de colite infecciosa bacteriana, associados a quadro clínico de infecção sistémica por Streptococcus gallolyticus e artrite do tornozelo.

  7. rpoB Mutation Conferring Rifampin Resistance in Streptococcus pyogenes

    OpenAIRE

    Aubry-Damon, Hélène; Galimand, Marc; Gerbaud, Guy; Courvalin, Patrice

    2002-01-01

    Streptococcus pyogenes BM4478 and Staphylococcus aureus BM4479 were isolated from a patient undergoing rifampin therapy. High-level resistance to rifampin was due to the following mutations in the rpoB gene: Ser522Leu in strain BM4478 and His526Asn and Ser574Leu in strain BM4479.

  8. Nutritionally variant Streptococcus pyogenes from a periorbital abscess.

    OpenAIRE

    Kocka, F. E.; Chittom, A L; Sanders, L.; Hernandez, L. (Luis); Soriano, E.; Jacobs, N.; Carey, R. B.

    1987-01-01

    A nutritionally variant Streptococcus pyogenes strain was isolated from a periorbital abscess. The organism was identified with the use of three rapid biochemical test kits, and the group A antigen was detected by conventional serology as well as direct antigen detection tests.

  9. Antimicrobial Drug Use and Macrolide-Resistant Streptococcus pyogenes, Belgium

    OpenAIRE

    Van Heirstraeten, Liesbet; Coenen, Samuel; Lammens, Christine; Hens, Niel; Goossens, Herman; Malhotra-Kumar, Surbhi

    2012-01-01

    In Belgium, decreasing macrolide, lincosamide, streptogramins B, and tetracycline use during 1997–2007 correlated significantly with decreasing macrolide-resistant Streptococcus pyogenes during 1999–2009. Maintaining drug use below a critical threshold corresponded with low-level macrolide-resistant S. pyogenes and an increased number of erm(A)-harboring emm77 S. pyogenes with low fitness costs.

  10. Streptococcus pyogenes aortic aneurysm infection: forgotten but not gone

    OpenAIRE

    Korman, Tony M.; Timothy Buckenham; Ming Yii; Bradley J. Gardiner; Joy Wong

    2013-01-01

    Historically, Streptococcus pyogenes was a common cause of endocarditis and infected aortic aneurysm. Today, endovascular infections due to this organism have become exceedingly rare. We report the first case of aortic aneurysm infection due to S. pyogenes treated with initial endoluminal repair, review previous reports and discuss current treatment options.

  11. Bullous impetigo caused by Streptococcus salivarius: a case report.

    OpenAIRE

    Brook, I

    1980-01-01

    A 19-month-old child presented with bullous impetigo around the perineal region, penis, and left foot. Streptococcus salivarius was the only isolate recovered from the lesions. The child was treated with parenteral penicillin, debridement of the bulli, and local application of silver sulphadiazine cream. This case of bullous impetigo illustrates another aspect of the pathogenicity of Strep. salivarius.

  12. Total synthesis of lipoteichoic acid of streptococcus pneumoniae

    OpenAIRE

    Pedersen, Christian Marcus; Figueroa-Perez, Ignacio; Lindner, Buko; Ulmer, Artur J.; Zähringer, Ulrich; Schmidt, Richard R.

    2010-01-01

    Streptococcus pneumoniae is one of the most common Grampositive pathogens. Upon colonizing the upper respiratory tract it causes severe infections and it causes life-threatening diseases like pneumonia, bacteremia, and meningitis when it reaches the lower respiratory tract or the bloodstream, thereby resulting in a high mortality rate.

  13. Specificity of natural antibodies reactive with Streptococcus mutans in monkeys.

    OpenAIRE

    Russell, R R; Beighton, D

    1982-01-01

    Enzyme-linked immunosorbent assays were used to measure levels of natural antibody to defined antigens of Streptococcus mutans in sera from monkeys (Macaca fascicularis). The results suggest that most of the antibody in young monkeys that binds to whole bacteria is not specific to S. mutans.

  14. Fundus lesions after carotid injection of Streptococcus mutans in monkeys.

    OpenAIRE

    Meyers, S M; Rodrigues, M.; Vasil, M. L.

    1982-01-01

    Carotid injection of Streptococcus mutans in pigtail monkeys caused fundus lesions clinically resembling those seen in humans with bacteremia. On histopathological examination microabscesses occurred in the retina, choroid, and optic nerve. Bacteria were observed in the histopathological sections of the microabscesses, and S. mutans was cultured from the retina and choroid.

  15. Draft Genome Sequences of Two Clinical Isolates of Streptococcus mutans

    OpenAIRE

    Zheng, Hui; Guo, Lihong; DU Ning; Lin, Jiuxiang; Song, Lai; Liu, Guiming; CHEN, Feng

    2014-01-01

    We report the draft genome sequences of PKUSS-HG01 and PKUSS-LG01, two clinical isolates of Streptococcus mutans from human dental plaque. The genomics information will facilitate the study of the mechanisms of pathogenicity and evolution of S. mutans.

  16. Recurrent Streptococcus equi subsp. zooepidemicus Bacteremia in an Infant.

    Science.gov (United States)

    Watson, Joshua R; Leber, Amy; Velineni, Sridhar; Timoney, John F; Ardura, Monica I

    2015-09-01

    We describe a case of an infant with recurrent bacteremia caused by Streptococcus equi subsp. zooepidemicus, likely transmitted from mother to infant. Our case highlights the importance of an epidemiological history and molecular diagnostics in ascertaining insights into transmission, pathogenesis, and optimal management. PMID:26179301

  17. Systems biology of the central metabolism of Streptococcus pyogenes

    OpenAIRE

    Levering, Jennifer

    2011-01-01

    Streptococcus pyogenes gehört zu den häufigsten Erregern von Haut- und Atemwegserkrankungen beim Menschen und verursacht verschiedene Krankheiten, von leichten Hautinfektionen bis hin zu schweren immunologisch bedingten Folgeerkrankungen der Streptokokkeninfektion, beispielsweise rheumatisches Fieber. Wie alle Milchsäurebakterien gewinnt S. pyogenes die zum Wachstum benötigte Energie mittels Substratkettenphosphorylierung in der Glykolyse. Das dabei gebildete Pyruvat wird hauptsächlich zu Lac...

  18. Extracellular chemiluminescence of isolated human leukocytes induced by Streptococcus mutans.

    Czech Academy of Sciences Publication Activity Database

    Kubala, Lukáš; Lojek, Antonín; ?íž, Milan; Nuutila, J.; Lilius, E. M.

    Island of Spetses : NATO, 2002. s. 53. [NATO / FEBS Advanced Study Institute - INTAS Symposium: Chemical Probes in Biology. 18.08.2002-30.08.2002, Island of Spetses] R&D Projects: GA ?R GP524/02/P005 Keywords : reactive oxygen species (ROS) * Streptococcus mutans * chemiluminescence Subject RIV: BO - Biophysics

  19. A new tool for transcription regulation in Streptococcus pneumoniae.

    Czech Academy of Sciences Publication Activity Database

    Nováková, Linda; P?enosilová, Lenka; Sušická, Zuzana; Jane?ek, Ji?í; Novotná, Jana; Ulrych, Aleš; Branny, Pavel

    Washington : American Society for Microbiology, 2006, s. 72-73. ISBN 1-55581-400-X. [ASM Conferences Streptococcal Genetics. Saint Malo (FR), 18.06.2006-21.06.2006] Institutional research plan: CEZ:AV0Z50200510 Keywords : streptococcus pneumoniae * rnap Subject RIV: EE - Microbiology, Virology

  20. Outbreak of Streptococcus pneumoniae in a Psychiatric Unit

    Centers for Disease Control (CDC) Podcasts

    2012-11-02

    Dr. Katherine Fleming-Dutra, an epidemiologist at CDC, discusses her investigation of a Streptococcus pneumoniae outbreak in a pediatric psychiatric unit.  Created: 11/2/2012 by National Center for Emerging and Zoonotic Infectious Diseases (NCEZID); National Center for Immunization and Respiratory Diseases (NCIRD).   Date Released: 11/5/2012.

  1. Streptococcus bovis as a Silage Inoculant, a Second Chance

    Science.gov (United States)

    Previous research indicated that Streptococcus bovis, a lactate producing ruminal bacterium, was similar or better than commercial silage inoculants. This study assessed the potential of two S. bovis strains, JB1 (a bacteriocin negative strain) and HC5 (a bacteriocin producing strain). Four treatmen...

  2. Screening Protocols for Group B Streptococcus: Are Transport Media Appropriate?

    Directory of Open Access Journals (Sweden)

    Nicolette Teese

    2003-01-01

    Full Text Available Objective: To evaluate group B streptococcus (GBS detection in an in vitro setting, using a low and controlled inoculum from swabs directly inoculated into a selective medium, as compared to delayed inoculation following a period in a commercial Amies transport medium with charcoal (Venturi Transystem™ Copan, Italy.

  3. Population diversity and dynamics of Streptococcus mitis, Streptococcus oralis, and Streptococcus infantis in the upper respiratory tracts of adults, determined by a nonculture strategy.

    DEFF Research Database (Denmark)

    Bek-Thomsen, Malene; Tettelin, H

    2008-01-01

    We reinvestigated the clonal diversity and dynamics of Streptococcus mitis and two other abundant members of the commensal microbiota of the upper respiratory tract, Streptococcus oralis and Streptococcus infantis, to obtain information about the origin of frequently emerging clones in this habitat. A culture-independent method was used, based on cloning and sequencing of PCR amplicons of the housekeeping gene gdh, which shows remarkable, yet species-specific, genetic polymorphism. Samples were collected from all potential ecological niches in the oral cavity and pharynx of two adults on two occasions separated by 2 years. Based on analysis of close to 10,000 sequences, significant diversity was observed in populations of all three species. Fluctuations in the relative proportions of individual clones and species were observed over time. While a few clones dominated, the proportions of most clones were very small. The results show that the frequent turnover of S. mitis, S. oralis, and S. infantis clones observed by cultivation can be explained by fluctuations in the relative proportions of clones, most of which are below the level of detection by the traditional culture technique, possibly combined with loss and acquisition from contacts. These findings provide a platform for understanding the mechanisms that govern the balance within the complex microbiota at mucosal sites and between the microbiota and the mucosal immune system of the host.

  4. Interactions between endocarditis-derived Streptococcus gallolyticus subsp. gallolyticus isolates and human endothelial cells

    Directory of Open Access Journals (Sweden)

    Dreier Jens

    2010-03-01

    Full Text Available Abstract Background Streptococcus gallolyticus subsp. gallolyticus is an important causative agent of infective endocarditis (IE but the knowledge on virulence factors is limited and the pathogenesis of the infection is poorly understood. In the present study, we established an experimental in vitro IE cell culture model using EA.hy926 and HUVEC cells to investigate the adhesion and invasion characteristics of 23 Streptococcus gallolyticus subsp. gallolyticus strains from different origins (human IE-derived isolates, other human clinical isolates, animal isolates. Adhesion to eight components of the extracellular matrix (ECM and the ability to form biofilms in vitro was examined in order to reveal features of S. gallolyticus subsp. gallolyticus endothelial infection. In addition, the strains were analyzed for the presence of the three virulence factors gtf, pilB, and fimB by PCR. Results The adherence to and invasion characteristics of the examined S. gallolyticus subsp. gallolyticus strains to the endothelial cell line EA.hy926 differ significantly among themselves. In contrast, the usage of three different in vitro models (EA.hy926 cells, primary endothelial cells (HUVECs, mechanical stretched cells revealed no differences regarding the adherence to and invasion characteristics of different strains. Adherence to the ECM proteins collagen I, II and IV revealed the highest values, followed by fibrinogen, tenascin and laminin. Moreover, a strong correlation was observed in binding to these proteins by the analyzed strains. All strains show the capability to adhere to polystyrole surfaces and form biofilms. We further confirmed the presence of the genes of two known virulence factors (fimB: all strains, gtf: 19 of 23 strains and demonstrated the presence of the gene of one new putative virulence factor (pilB: 9 of 23 strains by PCR. Conclusion Our study provides the first description of S. gallolyticus subsp. gallolyticus adhesion and invasion of human endothelial cells, revealing important initial information of strain variability, behaviour and characteristics of this as yet barely analyzed pathogen.

  5. Confirmation of Nontypeable Streptococcus pneumoniae-Like Organisms Isolated from Outbreaks of Epidemic Conjunctivitis as Streptococcus pneumoniae

    OpenAIRE

    Carvalho, Maria Gloria S.; Steigerwalt, Arnold G; Thompson, Terry; Jackson, Delois; Facklam, Richard R.

    2003-01-01

    Eleven isolates representing five distinct outbreaks of pneumococcal conjunctivitis were examined for phenotypic and genetic characteristics. None of the strains possessed capsules, and all strains were susceptible to optochin, bile soluble, and Gen-Probe AccuProbe test positive. All 11 isolates were confirmed as Streptococcus pneumoniae by DNA-DNA reassociation experiments.

  6. Celulitis por Streptococcus equi: reporte de caso y revisión de la literatura / Streptococcus equi Cellulitis: Case Report and Literature Review

    Scientific Electronic Library Online (English)

    Julio César, García Casallas; Francisco, Cuervo Millán; Luis Felipe, Kling; M. Angelica, Palencia Boada.

    2013-09-01

    Full Text Available El Streptococcus equi es un coco gram positivo, perteneciente al grupo C de Lancefield, causa una enfermedad de gran relevancia en caballos, la gurma o adenitis equina (1-2); en humanos, estas infecciones son poco frecuentes, siendo más frecuentes las infecciones de piel y tejidos blandos, faringiti [...] s, neumonía, síndrome tóxico similar al shock y endocarditis. Cuando la infección está asociada a bacteriemia, la mortalidad reportada es del 25%.(3) Presentamos el caso de un hombre de 44 años que ingresa al servicio de urgencias de la Clínica universidad de la Sabana con un cuadro clínico de celulitis en mano derecha por Streptococcus equi . Abstract in english Streptococcus equi is a gram-positive cocci, from group C of Lance 􀃀 eld. It causes an important disease in horses, strangles or equine adenitis (1-2). In humans, these infections are rare, and skin and soft tissue infections, pharyngitis, pneumonia, toxic shock-like syndrome and endocardit [...] is are more frequently observed. When the infection is associated with bacteremia, the reported mortality is near 25% (3). We report the case of a 44-year old man who was admitted to the emergency department of the University of Sabana Clinic with cellulitis due to Streptococcus equi in his right hand.

  7. Genetic polymorphism of Streptococcus mutans in Brazilian family members Polimorfismo genético de Streptococcus mutans em membros de famílias brasileiras

    Directory of Open Access Journals (Sweden)

    Denise Madalena Palomari Spolidorio

    2003-07-01

    Full Text Available The aim of this study was to determine whether random amplified polymorphic DNA (AP-PCR analysis is able to differentiate genetically different clones of mutans streptococci, in 22 Brazilian family members. Stimulated saliva samples were collected from fathers, mothers and infants. For 5-18 months babies with erupting primary dentition, plaque samples were collected using sterile tooth pick tips. From these samples, mutans streptococci were isolated on SB-20 agar plates. After growth, representative colonies were identified by biochemical methods on the basis of carbohydrate fermentation. Streptococcus mutans isolates were obtained from all family members and AP-PCR typed separately with a random primer (OPA-13. Bacterial cell lysates were used as template in PCR reactions and the amplified DNA fragments obtained were compared by agarose gel electrophoresis. Results demonstrated that the father shared the baby's genotype in three families and the mother shared the baby's genotype in 12 families seven babies harbored Streptococcus mutans strains similar to those of their siblings. The technique was able to demonstrate the genetic Streptococcus mutans in Brazilian family members.O objetivo deste estudo foi determinar, através da técnica de reação em cadeia da polimerase com primers arbitrários (AP-PCR a capacidade de diferenciar clones geneticamente distintos de Streptococcus mutans e estabelecer o grau de similaridade intrafamilial para os isolados. Para o presente estudo, foram selecionadas 22 famílias brasileiras. Amostras de saliva foram coletadas de todos os membros das famílias. Das crianças com idade entre 5-18 meses obteve-se amostras de placa dental. Após o isolamento das colônias com características morfológicas, realizou-se a identificação bioquímica com base na fermentação de carboidratos. O polimorfismo genético de Streptococcus mutans foi pesquisado através da técnica de AP-PCR utilizando-se o primer OPA-13. Os fragmentos de DNA obtidos foram amplificados e comparados através de eletroforese em gel de agarose. Dentre as espécies identificadas nas 22 famílias analisadas, o pai apresentou cepas com similaridade genética aos dos bebês em três das famílias analisadas; em 12 famílias a mãe apresentou cepas com similaridade com as cepas de Streptococcus mutans do bebê e 7 bebês apresentaram cepas de S. mutans com similaridade genética das cepas do irmão mais velho. A técnica de AP-PCR foi eficaz em demonstrar a heterogeneidade genética de Streptococcus mutans entre os membros das famílias brasileiras analisadas.

  8. Generation of human antibody fragments against Streptococcus mutans using a phage display chain shuffling approach

    Directory of Open Access Journals (Sweden)

    Barth Stefan

    2005-01-01

    Full Text Available Abstract Background Common oral diseases and dental caries can be prevented effectively by passive immunization. In humans, passive immunotherapy may require the use of humanized or human antibodies to prevent adverse immune responses against murine epitopes. Therefore we generated human single chain and diabody antibody derivatives based on the binding characteristics of the murine monoclonal antibody Guy's 13. The murine form of this antibody has been used successfully to prevent Streptococcus mutans colonization and the development of dental caries in non-human primates, and to prevent bacterial colonization in human clinical trials. Results The antibody derivatives were generated using a chain-shuffling approach based on human antibody variable gene phage-display libraries. Like the parent antibody, these derivatives bound specifically to SAI/II, the surface adhesin of the oral pathogen S. mutans. Conclusions Humanization of murine antibodies can be easily achieved using phage display libraries. The human antibody fragments bind the antigen as well as the causative agent of dental caries. In addition the human diabody derivative is capable of aggregating S. mutans in vitro, making it a useful candidate passive immunotherapeutic agent for oral diseases.

  9. Antibacterial Effect of Dental Adhesive Containing Dimethylaminododecyl Methacrylate on the Development of Streptococcus mutans Biofilm

    Directory of Open Access Journals (Sweden)

    Suping Wang

    2014-07-01

    Full Text Available Antibacterial bonding agents and composites containing dimethylaminododecyl methacrylate (DMADDM have been recently developed. The objectives of this study were to investigate the antibacterial effect of novel adhesives containing different mass fractions of DMADDM on Streptococcus mutans (S. mutans biofilm at different developmental stages. Different mass fractions of DMADDM were incorporated into adhesives and S. mutans biofilm at different developmetal stages were analyzed by MTT assays, lactic acid measurement, confocal laser scanning microscopy and scanning electron microscopy observations. Exopolysaccharides (EPS staining was used to analyze the inhibitory effect of DMADDM on the biofilm extracellular matrix. Dentin microtensile strengths were also measured. Cured adhesives containing DMADDM could greatly reduce metabolic activity and lactic acid production during the development of S. mutans biofilms (p < 0.05. In earlier stages of biofilm development, there were no significant differences of inhibitory effects between the 2.5% DMADDM and 5% DMADDM group. However, after 72 h, the anti-biofilm effects of adhesives containing 5% DMADDM were significantly stronger than any other group. Incorporation of DMADDM into adhesive did not adversely affect dentin bond strength. In conclusion, adhesives containing DMADDM inhibited the growth, lactic acid production and EPS metabolism of S. mutans biofilm at different stages, with no adverse effect on its dentin adhesive bond strength. The bonding agents have the potential to control dental biofilms and combat tooth decay, and DMADDM is promising for use in a wide range of dental adhesive systems and restoratives.

  10. New small-molecule inhibitors of dihydrofolate reductase inhibit Streptococcus mutans.

    Science.gov (United States)

    Zhang, Qiong; Nguyen, Thao; McMichael, Megan; Velu, Sadanandan E; Zou, Jing; Zhou, Xuedong; Wu, Hui

    2015-08-01

    Streptococcus mutans is a major aetiological agent of dental caries. Formation of biofilms is a key virulence factor of S. mutans. Drugs that inhibit S. mutans biofilms may have therapeutic potential. Dihydrofolate reductase (DHFR) plays a critical role in regulating the metabolism of folate. DHFR inhibitors are thus potent drugs and have been explored as anticancer and antimicrobial agents. In this study, a library of analogues based on a DHFR inhibitor, trimetrexate (TMQ), an FDA-approved drug, was screened and three new analogues that selectively inhibited S. mutans were identified. The most potent inhibitor had a 50% inhibitory concentration (IC50) of 454.0±10.2nM for the biofilm and 8.7±1.9nM for DHFR of S. mutans. In contrast, the IC50 of this compound for human DHFR was ca. 1000nM, a >100-fold decrease in its potency, demonstrating the high selectivity of the analogue. An analogue that exhibited the least potency for the S. mutans biofilm also had the lowest activity towards inhibiting S. mutans DHFR, further indicating that inhibition of biofilms is related to reduced DHFR activity. These data, along with docking of the most potent analogue to the modelled DHFR structure, suggested that the TMQ analogues indeed selectively inhibited S. mutans through targeting DHFR. These potent and selective small molecules are thus promising lead compounds to develop new effective therapeutics to prevent and treat dental caries. PMID:26022931

  11. Isolation of a Novel Phage with Activity against Streptococcus mutans Biofilms

    Science.gov (United States)

    Dalmasso, Marion; de Haas, Eric; Neve, Horst; Strain, Ronan; Cousin, Fabien J.; Stockdale, Stephen R.; Ross, R. Paul; Hill, Colin

    2015-01-01

    Streptococcus mutans is one of the principal agents of caries formation mainly, because of its ability to form biofilms at the tooth surface. Bacteriophages (phages) are promising antimicrobial agents that could be used to prevent or treat caries formation by S. mutans. The aim of this study was to isolate new S. mutans phages and to characterize their antimicrobial properties. A new phage, ?APCM01, was isolated from a human saliva sample. Its genome was closely related to the only two other available S. mutans phage genomes, M102 and M102AD. ?APCM01 inhibited the growth of S. mutans strain DPC6143 within hours in broth and in artificial saliva at multiplicity of infections as low as 2.5x10-5. In the presence of phage ?APCM01 the metabolic activity of a S. mutans biofilm was reduced after 24 h of contact and did not increased again after 48 h, and the live cells in the biofilm decreased by at least 5 log cfu/ml. Despite its narrow host range, this newly isolated S. mutans phage exhibits promising antimicrobial properties. PMID:26398909

  12. Antagonism between penicillin and erythromycin against Streptococcus pneumoniae in vitro and in vivo

    DEFF Research Database (Denmark)

    Johansen, H K; Jensen, T G

    2000-01-01

    The combination of beta-lactam antibiotics and macrolides is often recommended for the initial empirical treatment of acute pneumonia in order to obtain activity against the most important pathogens. Theoretically, this combination may be inexpedient, as the bacteriostatic agent may antagonize the effect of the bactericidal agent. In this study, the possible interaction between penicillin and erythromycin was investigated in vitro and in vivo against four clinical isolates of Streptococcus pneumoniae with MICs of penicillin ranging from 0.016 to 0.5 mg/L and of erythromycin from 0. 25 to >128 mg/L. In vitro time-kill curves were generated with clinically relevant concentrations of penicillin (10 mg/L) and erythromycin (1 mg/L), either individually or in combination. Antagonism between penicillin and erythromycin was observed for the four isolates. In vivo interaction was investigated in the mouse peritonitis model. After intraperitoneal inoculation, penicillin and erythromycin were given either individually or in combination. For two of the four isolates, mortality was significantly higher in the groups treated with the combination of penicillin and erythromycin than in the groups treated with penicillin alone [32/36 (86%) vs. 3/12 (25%), P

  13. Autonomous agents

    CERN Document Server

    Bekey, George

    2012-01-01

    Introduction; G. Bekey. Development of an Autonomous Quadruped Robot for Robot Entertainment; M. Fujita, K. Kitano. Basic Visual and Motor Agents for Increasingly Complex Behavior Generation on a Mobile Robot; M.C. Garcia-Alegre, F. Recio. An Autonomous Spacecraft Agent Prototype; B. Pell, et al. Map Generation by Cooperative Low-Cost Robots in Structured Unknown Environments; M. Lp?ez-Sn?chez, et al. Grounding Mundane Inference in Perception; I. Horswill. Interleaving Planning and Robot Execution for Asynchronous User Requests; K.Z. Haigh, M.V. Veloso. Integrated Premission Planning

  14. Riot Control Agents

    Science.gov (United States)

    ... Case Definition: Caustic or Corrosive Agents Incapacitating Agents Metals Nerve Agents Pulmonary Agents Riot Control Agents Toxic ... following symptoms immediately after exposure: Eyes: excessive tearing, burning, blurred vision, redness Nose: runny nose, burning, swelling ...

  15. Growth inhibition of Streptococcus mutans by cellular extracts of human intestinal lactic acid bacteria.

    OpenAIRE

    Ishihara, K.; Miyakawa, H; Hasegawa, A.; Takazoe, I; Kawai, Y

    1985-01-01

    The in vitro growth of Streptococcus mutans was completely inhibited by water-soluble extracts from cells of various intestinal lactic acid bacteria identified as Streptococcus faecium, Streptococcus equinus, Lactobacillus fermentum, and Lactobacillus salivarius. The growth inhibition was dependent on the concentrations of the extracts. In contrast, the extracts did not inhibit the growth of the major indigenous intestinal lactic acid bacteria isolated from humans. These lactic acid bacteria ...

  16. Group B Streptococcus detection: comparison of PCR assay and culture as a screening method for pregnant women

    Directory of Open Access Journals (Sweden)

    Fernanda de-Paris

    2011-08-01

    Full Text Available Streptococcus agalactiae or group B Streptococcus (GBS is one of the most important causal agents of serious neonatal infections. Numerous assays have been evaluated for GBS screening in order to validate a fast and efficient method. The aim of this study was to compare the culture technique (established as the gold standard with the molecular method of polymerase chain reaction (PCR with specific primers (atr gene. Two hundred and sixty-three samples were analyzed. Vaginal samples were collected, according to the Centers for Disease Control and Prevention (CDC recommendations, from women over 35 weeks of pregnancy at Hospital de Clínicas de Porto Alegre (HCPA. Two different extraction methods were tested in all samples collected. PCR technique yielded 71 (26.99% positive results. Sensitivity and specificity for PCR were 100% and 86.88%, respectively. PCR demonstrated a shorter turnaround time than the culture. The molecular methodology proved to be a useful screening for GBS, allowing effective treatment to be initiated in shorter time to prevent newborn infection.

  17. Group B Streptococcus detection: comparison of PCR assay and culture as a screening method for pregnant women

    Scientific Electronic Library Online (English)

    Fernanda, de-Paris; Alice Beatriz Mombach Pinheiro, Machado; Tailise Conte, Gheno; Bruna Maria, Ascoli; Kátia Ruschel Pilger de, Oliveira; Afonso Luis, Barth.

    2011-08-01

    Full Text Available Streptococcus agalactiae or group B Streptococcus (GBS) is one of the most important causal agents of serious neonatal infections. Numerous assays have been evaluated for GBS screening in order to validate a fast and efficient method. The aim of this study was to compare the culture technique (estab [...] lished as the gold standard) with the molecular method of polymerase chain reaction (PCR) with specific primers (atr gene). Two hundred and sixty-three samples were analyzed. Vaginal samples were collected, according to the Centers for Disease Control and Prevention (CDC) recommendations, from women over 35 weeks of pregnancy at Hospital de Clínicas de Porto Alegre (HCPA). Two different extraction methods were tested in all samples collected. PCR technique yielded 71 (26.99%) positive results. Sensitivity and specificity for PCR were 100% and 86.88%, respectively. PCR demonstrated a shorter turnaround time than the culture. The molecular methodology proved to be a useful screening for GBS, allowing effective treatment to be initiated in shorter time to prevent newborn infection.

  18. Comparison of antimicrobial efficacy of chlorhexidine and combination mouth rinse in reducing the Mutans streptococcus count in plaque

    Directory of Open Access Journals (Sweden)

    Laxmi S Lakade

    2014-01-01

    Full Text Available Background: The removal of plaque is utmost important to control dental caries. But in children, factors like lack of dexterity, individual motivation and monitoring limit the effectiveness of tooth brushing. This necessitates the use of chemotherapeutic agents for control of plaque. Aims: To compare the antimicrobial efficacy of 0.2% chlorhexidine mouth rinse and mouth rinse containing 0.03% triclosan, 0.05% sodium fluoride, and 5% xylitol in reducing the Mutans streptococcus count in plaque. Materials and Methods: Thirty healthy children aged 8-10 years with dmft (decay component of three or four were selected. They were divided randomly into two groups: The control or chlorhexidine group and the study group or combination mouth rinse. Both the groups practiced rinsing with respective mouth wash for 1 min for 15 d twice a day. The plaque samples were collected and after incubation Mutans streptococcus count was estimated on the strips from the Dentocult SM kit and evaluated using manufacture?s chart. Statistical Analysis Used: Wilcoxon matched pairs signed ranks test and Mann-Whitney U test were used to analyze the findings. Results: Statistically significant reduction in the Mutans streptococci count in the plaque was seen in the control and study group from baseline level. But when both the groups were compared, the antimicrobial effect of chlorhexidine was more.

  19. Colonización faucial por Streptococcus pyogenes en pacientes con impétigo

    Directory of Open Access Journals (Sweden)

    María Cristina Ronconi

    1999-01-01

    Full Text Available Se determinó la portación faucial de Streptococcus pyogenes en pacientes con impétigo, como factor de riesgo para la presentación de complicaciones no supurativas (glomerulonefritis aguda. Los cultivos de fauces de estos pacientes revelaron una colonización con S. pyogenes de 65 %, todos los aislamientos fueron sensibles a la penicilina. Se concluyó que este alto porcentaje de colonización faucial justificaba un tratamiento antibiótico sistémico.The faucial carrying of Streptococcus pyogenes in patients presenting impetigo was determined as a risk factor for non-suppurative complications (acute glomerulonephritis. The fauces cultures of these patients revealed a S. pyogenes colonization of 65 % and all the isolates were penicilline-sensitive. It was concluded that the high percent of faucial colonization made a systemic antimicrobial treatment necessary.

  20. Colonización faucial por Streptococcus pyogenes en pacientes con impétigo

    Scientific Electronic Library Online (English)

    María Cristina, Ronconi; Luis Antonio, Merino; Olga, Miranda.

    1999-12-01

    Full Text Available Se determinó la portación faucial de Streptococcus pyogenes en pacientes con impétigo, como factor de riesgo para la presentación de complicaciones no supurativas (glomerulonefritis aguda). Los cultivos de fauces de estos pacientes revelaron una colonización con S. pyogenes de 65 %, todos los aislam [...] ientos fueron sensibles a la penicilina. Se concluyó que este alto porcentaje de colonización faucial justificaba un tratamiento antibiótico sistémico. Abstract in english The faucial carrying of Streptococcus pyogenes in patients presenting impetigo was determined as a risk factor for non-suppurative complications (acute glomerulonephritis). The fauces cultures of these patients revealed a S. pyogenes colonization of 65 % and all the isolates were penicilline-sensiti [...] ve. It was concluded that the high percent of faucial colonization made a systemic antimicrobial treatment necessary.

  1. Molecular phylogeny and a taxonomic proposal for the genus Streptococcus.

    Science.gov (United States)

    Póntigo, F; Moraga, M; Flores, S V

    2015-01-01

    Alternative phylogenies for the genus Streptococcus have been proposed due to uncertainty about the among-species group relationships. Here, we performed a phylogenetic analysis of the genus Streptococcus, considering all the species groups and also the genomic data accumulated by other studies. Seventy-five species were subjected to a Bayesian phylogenetic analysis using sequences from eight genes (16S rRNA, rpoB, sodA, tuf, rnpB, gyrB, dnaJ, and recN). On the basis of our results, we propose a new Phylogeny for the genus, with special emphasis on the inter-species group level. This new phylogeny differs from those suggested previously. From topological and evolutionary distance criteria, we propose that gordonii, pluranimalium, and sobrinus should be considered as new species groups, in addition to the currently recognized groups of mutans, bovis, pyogenic, suis, mitis, and salivarius. PMID:26400318

  2. Streptococcus group C meningitis with cavernous sinus thrombosis

    Directory of Open Access Journals (Sweden)

    Clarke M

    2013-08-01

    Full Text Available Mattew Clarke,1 Hilary Enuh,1 Jessie Saverimuttu,2 Jay Nfonoyim31Department of Medicine, 2Division of Infectious Disease, 3Critical Care Unit, Richmond University Medical Center, Staten Island, NY, USAAbstract: Group C Streptococcus (GCS is a rare cause of bacteremia in humans. It is mostly associated with zoonological infections. Although GCS can be part of the normal oral, skin, and genitourinary flora, an infection with this pathogen can be highly virulent, causing rapid, disseminating disease. With a mortality of about 25%, the poor prognosis is linked to the severity of illness and the high level of virulence of the organism. Only a few cases of GCS meningitis have been reported. We present the first case of GCS meningitis with cavernous sinus thrombosis.Keyword: streptococcus group C, cavernous sinus thrombosis, meningitis

  3. [Fever, malaise and new onset mitral valve insufficiency. Subacute Streptococcus bovis mitral valve endocarditis ].

    Science.gov (United States)

    Burri, E; Laffer, R; Steuerwald, M; Cathomas, G; Zimmerli, W

    2004-05-01

    A 62-year-old patient with low grade fever, fatigue, arthralgia and newly discovered mitral regurgitation was diagnosed with subacute endocarditis. Streptococcus bovis grew from all six blood culture bottles. Streptococcus bovis is known to be associated with gastrointestinal neoplasias. Therefore a colonoscopy was performed and two polyps were removed. Histological analysis revealed a tubulovillous adenoma and a serrated adenoma. Colonoscopy is mandatory for all patients with Streptococcus bovis endocarditis even without any symptoms for colorectal neoplasia. The significance of Streptococcus bovis for the carcinogenesis of colorectal neoplasias and the possible alternative pathway for colorectal carcinomas through serrated adenomas will be discussed. PMID:15185488

  4. Evaluación de la colonización del tracto digestivo de cerdos por cepas de Lactobacillus acidophilus y Streptococcus termophilus, componentes de un producto probiótico / Gastrointestinal tract colonization evaluation in pigs by Lactobacillus acidophilus and Streptococcus thermophile strains, components of a probiotic product

    Scientific Electronic Library Online (English)

    Miguel, Pérez Ruano; Mabelin, Armenteros Amaya; Ernesto, Vega Cañizares.

    2014-12-01

    Full Text Available Con el objetivo de evaluar la posible utilización como probiótico, de un producto compuesto por Lactobacillus acidophilus y Streptococcus termophilus, se estudió la colonización del tracto intestinal de cerdos recién nacidos, por los agentes componentes de este producto. Como probiótico se utilizó u [...] na mezcla de miel de caña, levadura torula y agua hasta completar 1000 ml y 25 ml del cultivo de Lactobacillus acidophilus y Streptococcus termophilus. Se conformaron cuatro grupos experimentales de la siguiente manera: Grupo 1: 18 crías (camada de dos cerdas) a las cuales se les aplicó 5 ml del producto por vía oral al nacimiento; Grupo 2: 17 crías (camada de dos cerdas) a las cuales se les aplicó 5 ml del producto por vía oral al nacimiento y 24 horas después del primer tratamiento; Grupo 3: 10 crías (camada de una cerda) a las que se les aplicó 5 ml del placebo por vía oral al nacimiento; Grupo 4: 12 crías (camada de una cerda) a las cuales se les aplicó 5 ml del placebo por vía oral al nacimiento y 24 horas después del primer tratamiento. A todos los animales se les realizó un hizopaje rectal a los 7, 14 y 21 días de finalizado el tratamiento. Se comprobó la colonización del tracto gastrointestinal por Lactobacillus acidophilus y Streptococcus termophilus en los cerdos tratados con el producto probiótico hasta los 14 días postratamiento y que esta no se encuentra influida por la frecuencia de aplicación del probiótico. Abstract in english With the aim of evaluating the possible use as a probiotic product composed by Lactobacillus acidophilus and Streptococcus thermophilus, the intestinal tract colonization of newborn pigs was studied by the components of this product. As a probiotic, a mixture of 150 ml of molasses and 100 mg torula [...] yeast was used and water was added completing 1000 ml and 25 ml of Lactobacillus acidophilus and Streptococcus thermophilus culture was added. Four experimental groups were formed as follows: Group 1: 18 piglets (a litter of two sows) which was applied 5 ml of the probiotic product orally at birth; Group 2: 17 piglets (a litter of two sows) which were applied 5 ml of the probiotic product orally at birth and at 24 hours after the first treatment; Group 3: 10 piglets (a litter of one sow) which were applied 5 ml of placebo orally at birth and Group 4: 12 piglets (a litter of one sow) which were applied 5 ml of placebo orally at birth and at 24 hours after the first treatment. A microbiological sampling by rectal swabs at 7, 14 and 21 days postreatment was applied to all animals. The gastrointestinal tract colonization by Streptococcus thermophilus and Lactobacillus acidophilus was observed in pigs treated with the probiotic product until 14 days postreatment not being and this is not influenced by the frequency of probiotic application.

  5. Coaggregation of Streptococcus sanguis and other streptococci with Candida albicans.

    OpenAIRE

    Jenkinson, H F; Lala, H C; Shepherd, M. G.

    1990-01-01

    Thirteen strains of viridans group streptococci and two strains of other streptococci were tested for coaggregation with Candida albicans. Streptococcus sanguis strains generally exhibited low levels of adherence to 28 degrees C-grown exponential-phase yeast cells, but starvation of yeast cells for glucose at 37 degrees C (or at 28 degrees C) increased their coaggregating activity with these streptococci by at least tenfold. This was a property common to four C. albicans strains tested, two o...

  6. Oxygen Regulates Invasiveness and Virulence of Group B Streptococcus

    OpenAIRE

    Johri, Atul K.; Padilla, Joahnna; Malin, Gennady; Paoletti, Lawrence C.

    2003-01-01

    The facultative anaerobe group B Streptococcus (GBS) is an opportunistic pathogen of pregnant women, newborns, and the elderly. Although several virulence factors have been identified, environmental factors that regulate the pathogenicity of GBS have not been well characterized. Using the dynamic in vitro attachment and invasion system (DIVAS), we examined the effect of oxygen on the ability of GBS to invade immortalized human epithelial cells. GBS type III strain M781 invaded human epithelia...

  7. Group B Streptococcus: global incidence and vaccine development

    OpenAIRE

    Johri, Atul Kumar; Paoletti, Lawrence C.; Glaser, Philippe,; Dua, Meenakshi; Sharma, Puja Kumari; Grandi, Guido; Rappuoli, Rino

    2006-01-01

    An ongoing public health challenge is to develop vaccines that are effective against infectious diseases that have global relevance. Vaccines against serotypes of group B Streptococcus (GBS) that are prevalent in the United States and Europe are not optimally efficacious against serotypes common to other parts of the world. New technologies and innovative approaches are being used to identify GBS antigens that overcome serotype-specificity and that could form the basis of a globally effective...

  8. Transposon mutagenesis of group B streptococcus beta-hemolysin biosynthesis.

    OpenAIRE

    Weiser, J N; Rubens, C.E.

    1987-01-01

    Beta-hemolysin production by group B streptococci (GBS) is speculated to be a major virulence factor of the organism. A virulent, beta-hemolytic group B streptococcus strain was mutagenized with the self-conjugative transposon Tn916 to derive isogenic strains with mutations only in the gene(s) responsible for beta-hemolysin biosynthesis. There was no significant difference between the virulence of the parent strain and that of the mutant strains in a neonatal rat sepsis model.

  9. Phenotypical characteristics of group B streptococcus in parturients

    OpenAIRE

    Jose Antonio Simoes; Valeria Moraes Neder Alves; Sergio Eduardo Longo Fracalanzza; Rodrigo Pauperio Soares de Camargo; Lenir Mathias; Helaine Maria Besteti Pires Milanez; Eliane Melo Brolazo

    2007-01-01

    Colonization by Group B Streptococcus (GBS) is highly prevalent among pregnant women, with prevalence rates ranging between 4% and 30%. The infection may be transmitted vertically and may result in serious neonatal consequences. In the period from November 2003 to May 2004, a cross-sectional study was carried out among 316 parturients at the Jundiaí Teaching Hospital to establish the prevalence of genital GBS colonization, to identify the factors associated with colonization and the character...

  10. Isolation of Streptococcus pneumoniae type 3 from equine species.

    OpenAIRE

    Benson, C. E.; Sweeney, C R

    1984-01-01

    Streptococcus pneumoniae type 3 was isolated from seven tracheobronchial aspirates and one pleural tap of seven adult horses and one foal. There was no direct evidence in these horses that isolation of the pneumococcus was related to a specific disease syndrome. Presenting complaints included two horses with chronic cough, two horses with decreased exercise tolerance, one horse with exercise-induced pulmonary hemorrhage, and three horses with pneumonia. Antibiotic therapy resolved the primary...

  11. Glucosyltransferase from Streptococcus sobrinus Catalyzes Glucosylation of Catechin

    OpenAIRE

    Nakahara, K.; Kontani, M; Ono, H.; Kodama, T.; Tanaka, T; Ooshima, T; Hamada, S.

    1995-01-01

    We previously showed that the polymeric forms of polyphenols present in oolong tea extract exhibited strong inhibitory activities against glucosyltransferases (GTases) of mutans streptococci, while green tea extract, which is rich in catechins, did not show such GTase-inhibitory activities. In this study, (+)-catechin [2-(3,4-dihydroxyphenyl)-3,4-dihydro-2H-1-benzopyran-3,5,7-triol] was found to be glucosylated by the GTase of Streptococcus sobrinus 6715 with sucrose as the substrate, and the...

  12. In Vitro Antibacterial Activity of Essential Oils against Streptococcus pyogenes

    OpenAIRE

    Julien Sfeir; Corinne Lefrançois; Dominique Baudoux; Séverine Derbré; Patricia Licznar

    2013-01-01

    Streptococcus pyogenes plays an important role in the pathogenesis of tonsillitis. The present study was conducted to evaluate the in vitro antibacterial activities of 18 essential oils chemotypes from aromatic medicinal plants against S. pyogenes. Antibacterial activity of essential oils was investigated using disc diffusion method. Minimum Inhibitory Concentration of essential oils showing an important antibacterial activity was measured using broth dilution method. Out of 18 essential oils...

  13. Comparison of Streptokinase Activity from Streptococcus mutans using Different Substrates

    OpenAIRE

    Muhammad Anjum Zia*, Rana Faisal, Rao Zahid Abbas1, Gull-e-Faran, Muhammad Kashif Saleemi2 and Junaid Ali Khan3

    2013-01-01

    Streptokinase is a novel bacterial fibrinolytic enzyme that binds and activates plasminogen and is produced by several species of Streptococci. Streptococcus mutans was selected for optimum production of streptokinase using corn steep liquor, molasses, rice polishing and sugarcane bagass in liquid state fermentation. Substrates were applied in different concentrations ranging from 0.1-0.8%. Maximum fibrinolytic activity was observed by 0.3% corn steep liquor, 0.5% molasses and rice polishing ...

  14. Production and purification of Streptococcus pneumoniae hemolysin (pneumolysin).

    OpenAIRE

    Kanclerski, K; Möllby, R

    1987-01-01

    Pneumolysin was found to be produced by 112 of 113 clinical isolates of Streptococcus pneumoniae and to be an intracellular hemolysin. A 10-liter-scale fermentor production and purification procedure was developed for this hemolysin. The culture was concentrated by filtration 10 times before centrifugation. The cellular content was purified by ion-exchange chromatography, covalent thiopropyl gel chromatography, and gel filtration. One batch operation resulted in 6 mg of highly purified pneumo...

  15. Impacto de Streptococcus pneumoniae en las neumonías del niño latinoamericano

    OpenAIRE

    Hortal María; Ruvinsky Raúl; Rossi Alicia; Agudelo Clara I.; Castañeda Elizabeth; Brandileone Cristina; Camou Teresa; Palacio Rosario; Echaniz Gabriela; Di Fabio José L.

    2000-01-01

    La neumonía adquirida en la comunidad es una de las principales causas de morbilidad y mortalidad en la infancia. Estudios realizados en países en desarrollo indican que los cuadros de neumonía más graves se asocian a causas bacterianas, con predominio de Streptococcus pneumoniae, seguido por Haemophilus influenzae tipo b. El manejo de esas infecciones en los menores de 2 años se ve dificultado por la carencia de vacunas apropiadas y por la disminución de la susceptibilidad de S. pneumoniae a...

  16. Selection and application of Streptococcus bovis as a silage inoculant.

    OpenAIRE

    Jones, B. A.; Muck, R E; Ricke, S. C.

    1991-01-01

    Three strains of Streptococcus bovis, a homolactic bacterium capable of utilizing starch, were evaluated for growth kinetics and ability to decrease the pH of alfalfa silage. A selected strain was evaluated for its competitiveness as an inoculant with Enterococcus faecium, an organism used in inoculants, and for its ability to enhance the effect of a commercial inoculant. Testing was completed over three studies using wilted alfalfa (28 to 34% dry matter) ensiled into laboratory silos. Treatm...

  17. Platelet Aggregation Induced by Serotype Polysaccharides from Streptococcus mutans

    OpenAIRE

    Chia, Jean-San; Lin, Ya-Lin; Lien, Huei-Ting; Chen, Jen-Yang

    2004-01-01

    Platelet aggregation plays an important role in the pathogenesis of infective endocarditis induced by viridans streptococci or staphylococci. Aggregation induced in vitro involves direct binding of bacteria to platelets through multiple surface components. Using platelet aggregometry, we demonstrated in this study that two Streptococcus mutans laboratory strains, GS-5 and Xc, and two clinical isolates could aggregate platelets in an irreversible manner in rabbit platelet-rich plasma preparati...

  18. Characterization of Colony Morphology Variants Isolated from Streptococcus pneumoniae Biofilms?

    OpenAIRE

    Allegrucci, Magee; Sauer, Karin

    2006-01-01

    In this study, we report the isolation of colony morphology variants from Streptococcus pneumoniae serotype 3 biofilms. The colony variants differed in colony size (large, medium, and small) and their mucoid appearance on blood agar. The small nonmucoid variant (SCV) emerged during the initial attachment stage of S. pneumoniae biofilm formation and dominated over the course of biofilm growth. Mucoid variants appeared at later biofilm developmental stages. The reduction in colony size/mucoidy ...

  19. Streptococcus group C meningitis with cavernous sinus thrombosis

    OpenAIRE

    Clarke M; Enuh H; Saverimuttu J; Nfonoyim J

    2013-01-01

    Mattew Clarke,1 Hilary Enuh,1 Jessie Saverimuttu,2 Jay Nfonoyim31Department of Medicine, 2Division of Infectious Disease, 3Critical Care Unit, Richmond University Medical Center, Staten Island, NY, USAAbstract: Group C Streptococcus (GCS) is a rare cause of bacteremia in humans. It is mostly associated with zoonological infections. Although GCS can be part of the normal oral, skin, and genitourinary flora, an infection with this pathogen can be highly virulent, causing rapid, disseminating di...

  20. Development of Streptococcus pneumoniae Vaccines Using Live Vectors

    OpenAIRE

    Shifeng Wang; Roy Curtiss III

    2014-01-01

    Streptococcus pneumoniae still causes severe morbidity and mortality worldwide, especially in young children and the elderly. Much effort has been dedicated to developing protein-based universal vaccines to conquer the current shortcomings of capsular vaccines and capsular conjugate vaccines, such as serotype replacement, limited coverage and high costs. A recombinant live vector vaccine delivering protective antigens is a promising way to achieve this goal. In this review, we discuss the res...

  1. Fatal Necrotizing Fasciitis Due to Streptococcus pneumoniae: A Case Report

    OpenAIRE

    Park, So-Youn; Park, So Young; Moon, Soo-Youn; Son, Jun Seong; Lee, Mi Suk

    2010-01-01

    Necrotizing fasciitis is known to be a highly lethal infection of deep-seated subcutaneous tissue and superficial fascia. Reports of necrotizing fasciitis due to Streptococcus pneumoniae are exceedingly rare. We report a case of necrotizing fasciitis in a 62-yr-old man with liver cirrhosis and diabetes mellitus. He presented with painful swelling of left leg and right hand. On the day of admission, compartment syndrome was aggravated and the patient underwent surgical exploration. Intra-opera...

  2. Invasive Streptococcus pneumoniae in Children, Malawi, 2004–2006

    OpenAIRE

    Cornick, Jennifer E.; Everett, Dean B.; Broughton, Caroline; Denis, Brigitte B.; Banda, Daniel L; Carrol, Enitan D; Parry, Christopher M

    2011-01-01

    Of 176 invasive Streptococcus pneumoniae isolates from children in Malawi, common serotypes were 1 (23%), 6A/B (18%), 14 (6%), and 23F (6%). Coverage with the 7-valent pneumococcal conjugate vaccine (PCV) was 39%; PCV10 and PCV13 increased coverage to 66% and 88%, respectively. We found chloramphenicol resistance in 27% of isolates and penicillin nonsusceptibility in 10% (by using meningitis breakpoints); all were ceftriaxone susceptible.

  3. Invasive Streptococcus pneumoniae in children, Malawi, 2004-2006.

    Science.gov (United States)

    Cornick, Jennifer E; Everett, Dean B; Broughton, Caroline; Denis, Brigitte B; Banda, Daniel L; Carrol, Enitan D; Parry, Christopher M

    2011-06-01

    Of 176 invasive Streptococcus pneumoniae isolates from children in Malawi, common serotypes were 1 (23%), 6A/B (18%), 14 (6%), and 23F (6%). Coverage with the 7-valent pneumococcal conjugate vaccine (PCV) was 39%; PCV10 and PCV13 increased coverage to 66% and 88%, respectively. We found chloramphenicol resistance in 27% of isolates and penicillin nonsusceptibility in 10% (by using meningitis breakpoints); all were ceftriaxone susceptible. PMID:21749782

  4. "THE RESISTANCE OF STREPTOCOCCUS PNEUMONIAE AGAINST PENICILLIN AND OTHER ANTIBIOTICS"

    OpenAIRE

    M. Soltani Radd Gh. Behzadian Nejad; A Rajabi; S.A.H. Jahanmehr

    2004-01-01

    Resistance of Streptococcus pneumoniae against penicillin is considered to be of great importance. While low-resistant strains could be treated by penicillin, treatment of highly resistant strains is very difficult and needs broad-spectrum antibiotics. This study was performed in Imam Khomeini Medical Center, Tehran, Iran, from 1999 to 2001 to evaluate pneumococcal resistance against penicillin and some other antibiotics. Specimens were collected from different hospitals. Samples were culture...

  5. Granulocyte phagocytosis of Streptococcus pneumoniae in properdin-deficient serum.

    OpenAIRE

    Braconier, J. H.; Odeberg, H; Sjöholm, A G

    1983-01-01

    Properdin (P)-deficient human serum containing type-specific anticapsular antibodies and having an intact classical pathway of complement did not support efficient granulocyte phagocytosis of Streptococcus pneumoniae serotypes 6A, 14, 19F, 23F, or 35 in an opsonophagocytic assay. Compared with pooled control serum, the difference was most pronounced for serotypes 14 and 23F and at a final serum concentration of 16%. The reduced phagocytic killing of S. pneumoniae serotype 23F in P-deficient s...

  6. Suppurative keratitis caused by Streptococcus pneumoniae after cataract surgery.

    OpenAIRE

    Charteris, D G; Batterbury, M.; Armstrong, M.; Tullo, A B

    1994-01-01

    Six elderly patients are described (age range 76-86 years) in whom a characteristic peripheral suppurative keratitis developed 1-36 months after uncomplicated cataract surgery. A corneal section had been used in all patients and four or five interrupted nylon sutures were present at the time of onset. Streptococcus pneumoniae was cultured from a corneal scrape in all cases. Treatment with appropriate antibiotics resulted in slow resolution though supplementary topical steroids were necessary ...

  7. Properties of a Streptococcus lactis strain that ferments lactose slowly.

    OpenAIRE

    Crow, V. L.; Thomas, T. D.

    1984-01-01

    Streptococcus lactis 7962, which ferments lactose slowly, has a lactose phosphoenolpyruvate-dependent phosphotransferase system and low phospho-beta-galactosidase activity, in addition to high beta-galactosidase activity. Lactose 6'-phosphate accumulated to a high concentration (greater than 100 mM) in cells growing on lactose. In contrast, lactic streptococci, which ferment lactose rapidly and use only the lactose-phosphotransferase system for uptake, contained high phospho-beta-galactosidas...

  8. Streptococcus pneumoniae and its bacteriophages: one long argument

    OpenAIRE

    López, Rubens

    2004-01-01

    Infectious diseases currently kill more than 15 million people annually, and the WHO estimates that every year 1.6 million people die from pneumococcal diseases. Streptococcus pneumoniae (pneumococcus), a bacterium with a long biological pedigree, best illustrates the rapid evolution of antibiotic resistance, which has led to major public health concern. This article discusses the molecular basis of the two main virulence factors of pneumococcus, the capsule and cell-wall hydrolases, as well ...

  9. Ecology of Streptococcus faecium bacteriophage in chicken gut.

    OpenAIRE

    Houghton, S. B.; Fuller, R

    1980-01-01

    The interaction in the chick gut between Streptococcus faecium and its phage was examined. In conventional chicks, large numbers of S. faecium and phage were found in the cecum and smaller numbers were found in the anterior gut. In gnotobiotic chicks associated with S. faecium SY1 and its phage, there was no marked effect on bacterial numbers, but resistance to the phage rapidly developed. Depression of chick growth caused by S. faecium strain SY1 was partially reversed by its phage.

  10. Pherotypes are driving genetic differentiation within Streptococcus pneumoniae

    OpenAIRE

    Ramirez Mario; Melo-Cristino Jose; Pinto Francisco R; Carrolo Margarida

    2009-01-01

    Abstract Background The boundaries of bacterial species and the mechanisms underlying bacterial speciation are matters of intense debate. Theoretical studies have shown that recombination acts as a strong cohesive force preventing divergence in bacterial populations. Streptococcus pneumoniae populations have the telltale signs of high recombination with competence implicated as the major driving force behind gene exchange. Competence in S. pneumoniae is triggered by a quorum-sensing mechanism...

  11. The Streptococcus pyogenes proteome: maps, virulence factors and vaccine candidates

    OpenAIRE

    Dmitriev, Alexander V.; Chaussee, Michael S

    2010-01-01

    Streptococcus pyogenes is an important cause of human morbidity and mortality worldwide. A wealth of genomic information related to this pathogen has facilitated exploration of the proteome, particularly in response to environmental conditions thought to mimic various aspects of pathogenesis. Proteomic approaches are also used to identify immunoreactive proteins for vaccine development and to identify proteins that may induce autoimmunity. These studies have revealed new mechanisms involved i...

  12. The role of coagulation/fibrinolysis during Streptococcus pyogenes infection

    OpenAIRE

    Loof, Torsten G.; Deicke, Christin; Medina, Eva

    2014-01-01

    The hemostatic system comprises platelet aggregation, coagulation and fibrinolysis and is a host defense mechanism that protects the integrity of the vascular system after tissue injury. During bacterial infections, the coagulation system cooperates with the inflammatory system to eliminate the invading pathogens. However, pathogenic bacteria have frequently evolved mechanisms to exploit the hemostatic system components for their own benefit. Streptococcus pyogenes, also known as Group A Stre...

  13. Bovine mammary epithelial cell invasion by Streptococcus uberis.

    OpenAIRE

    Matthews, K.R.; Almeida, R A; Oliver, S P

    1994-01-01

    Streptococcus uberis commonly causes bovine mastitis; however, the pathogenesis of this infection is poorly understood. In this study, the ability of S. uberis to invade mammary epithelial cells in culture was investigated. Two strains of S. uberis isolated from bovine mammary secretions were capable of invading bovine mammary epithelial cells in vitro at different levels, suggesting strain differences in invasiveness. Invasion required microfilaments but not microtubular cytoskeletal element...

  14. Streptococcus mutans Clonal Variation Revealed by Multilocus Sequence Typing?

    OpenAIRE

    Nakano, Kazuhiko; Lapirattanakul, Jinthana; Nomura, Ryota; Nemoto, Hirotoshi; Alaluusua, Satu; Grönroos, Lisa; Vaara, Martti; Hamada, Shigeyuki; Ooshima, Takashi; NAKAGAWA, ICHIRO

    2007-01-01

    Streptococcus mutans is the major pathogen of dental caries, a biofilm-dependent infectious disease, and occasionally causes infective endocarditis. S. mutans strains have been classified into four serotypes (c, e, f, and k). However, little is known about the S. mutans population, including the clonal relationships among strains of S. mutans, in relation to the particular clones that cause systemic diseases. To address this issue, we have developed a multilocus sequence typing (MLST) scheme ...

  15. Streptococcus suis Meningitis with Bilateral Sensorineural Hearing Loss

    OpenAIRE

    Huh, Hee Jae; Park, Kyoung-Jin; Jang, Ja-Hyun; Lee, Mina; Lee, Jang Ho; Ahn, Yoon Hee; Kang, Cheol-In; Ki, Chang-Seok; Lee, Nam Yong

    2011-01-01

    Streptococcus suis infection is an emerging zoonosis in Asia. The most common disease manifestation is meningitis, which is often associated with hearing loss and cochleovestibular signs. S. suis infection in humans mainly occurs among risk groups that have frequent exposure to pigs or raw pork. Here, we report a case of S. suis meningitis in a 67-yr-old pig carcass handler, who presented with dizziness and sensorineural hearing loss followed by headaches. Gram-positive diplococci were isolat...

  16. Serotyping of Streptococcus pneumoniae strains by coagglutination and counterimmunoelectrophoresis.

    OpenAIRE

    Trollfors, B; Burman, L; Dannetun, E; Llompart, J; Norrby, R

    1983-01-01

    A total of 217 Streptococcus pneumoniae strains were serotyped by coagglutination (COA) and counterimmunoelectrophoresis (CIE). With all strains tested, there was full agreement between results obtained by COA and CIE, except for strains belonging to serotypes 7, 14, 33, and 37, which could not be typed by CIE. These strains were serotyped by passive immunodiffusion, results of which were in full agreement with those obtained by COA. Besides having the advantage of identifying strains belongi...

  17. Streptococcus anginosus pyogenic liver abscess following a screening colonoscopy

    OpenAIRE

    Bonenfant, Francis; Rousseau, Étienne; Farand, Paul

    2013-01-01

    A previously healthy 58-year-old man presented with a septic thrombosis of the right hepatic vein and a pyogenic liver abscess (PLA) one week after undergoing a screening colonoscopy. Blood cultures and a radiological drainage specimen were both positive for Streptococcus anginosus. Evolution was favourable after six weeks of antibiotherapy. To the authors’ knowledge, the present report is the first to describe a PLA following a screening colonoscopy with no intervention. The authors hypothes...

  18. Metabolic Engineering of Acetaldehyde Production by Streptococcus thermophilus

    OpenAIRE

    Chaves, A. C. S. D.; Fernandez, M.; Lerayer, A. L. S.; Mierau, I.; Kleerebezem, M; Hugenholtz, J

    2002-01-01

    The process of acetaldehyde formation by the yogurt bacterium Streptococcus thermophilus is described in this paper. Attention was focused on one specific reaction for acetaldehyde formation catalyzed by serine hydroxymethyltransferase (SHMT), encoded by the glyA gene. In S. thermophilus, SHMT also possesses threonine aldolase (TA) activity, the interconversion of threonine into glycine and acetaldehyde. In this work, several wild-type S. thermophilus strains were screened for acetaldehyde pr...

  19. Localization of Surface Immunogenic Protein on Group B Streptococcus

    OpenAIRE

    Rioux, Stéphane; Martin, Denis; Ackermann, Hans-Wolfgang; Dumont, Julie; Hamel, Josée; Brodeur, Bernard R.

    2001-01-01

    The localization and accessibility of the group B streptococcus (GBS) surface immunogenic protein (Sip) at the surface of intact GBS cells were studied by flow cytometric assay and immunogold electron microscopy. Antibodies present in pooled sera collected from mice after immunization with purified recombinant Sip efficiently recognized native Sip at the surfaces of the different GBS strains tested, which included representatives of all nine serotypes. Examination of GBS cells by immunogold e...

  20. Activities of Newer Fluoroquinolones against Ciprofloxacin-Resistant Streptococcus pneumoniae

    OpenAIRE

    Coyle, Elizabeth A.; Kaatz, Glenn W.; Rybak, Michael J.

    2001-01-01

    The incidence of ciprofloxacin resistance in Streptococcus pneumoniae is low but steadily increasing, which raises concerns regarding the clinical impact of potential cross-resistance with newer fluoroquinolones. To investigate this problem, we utilized an in vitro pharmacodynamic model and compared the activities of gatifloxacin, grepafloxacin, levofloxacin, moxifloxacin, and trovafloxacin to that of ciprofloxacin against two laboratory-derived, ciprofloxacin-resistant derivatives of S. pneu...

  1. Detection of pathogenic Streptococcus suis bacteria using magnetic glycoparticles

    OpenAIRE

    Pera, N.P.; Kouki, A.; Haataja, S; Branderhorst, H.M.; Liskamp, R. M. J.; Visser, G. M.; Finne, J; Pieters, R. J.

    2010-01-01

    Detection of the zoonotic bacterial pathogen Streptococcus suis was achieved using magnetic glycoparticles. The bacteria contain an adhesion protein for the carbohydrate sequence Gal alpha 1,4Gal. After incubation with various amounts of the pathogen, magnetic concentration and ATP detection, bacterial levels down to 10(5) cfu could be detected. Submicrometer particles were needed, since with the larger microparticles the method did not succeed.

  2. Use of a bacteriophage lysin, PlyC, as an enzyme disinfectant against Streptococcus equi.

    Science.gov (United States)

    Hoopes, J Todd; Stark, Caren J; Kim, Han Ah; Sussman, Daniel J; Donovan, David M; Nelson, Daniel C

    2009-03-01

    Streptococcus equi is the causative agent of the purulent infection equine strangles. This disease is transmitted through shedding of live bacteria from nasal secretions and abscess drainage or by contact with surfaces contaminated by the bacteria. Disinfectants are effective against S. equi, but inactivation by environmental factors, damage to equipment, and toxicity are of great concern. Bacteriophage-encoded lysins (cell wall hydrolases) have been investigated as therapeutic agents due to their ability to lyse susceptible gram-positive organisms. Here, we investigate the use of one lysin, PlyC, as a narrow-spectrum disinfectant against S. equi. This enzyme was active against >20 clinical isolates of S. equi, including both S. equi subsp. equi and S. equi subsp. zooepidemicus. Significantly, PlyC was 1,000 times more active on a per weight basis than Virkon-S, a common disinfecting agent, with 1 microg of enzyme able to sterilize a 10(8) CFU/ml culture of S. equi in 30 min. PlyC was subjected to a standard battery of tests including the Use Dilution Method for Testing Disinfectants and the Germicidal Spray Products Test. Results indicate that aerosolized PlyC can eradicate or significantly reduce the S. equi load on a variety of materials found on common stable and horse-related equipment. Additionally, PlyC was shown to retain full activity under conditions that mimic a horse stable, i.e., in the presence of nonionic detergents, hard water, or organic materials. We propose PlyC as the first protein-based, narrow-spectrum disinfectant against S. equi, which may augment or supplement the use of broad-spectrum disinfectants in barns and stables where equine strangles is prevalent. PMID:19139235

  3. [Invasive disease due to Streptococcus pyogenes in a patient with A H1N1 influenza infection. Report of one case].

    Science.gov (United States)

    Guerrero S, Gonzalo; Marín S, Felipe

    2015-08-01

    Bacterial superinfection is a known complication among patients affected by viral respiratory tract infections. Streptococcus pyogenes, a major bacterial agent involved in acute tonsillopharyngitis, skin and soft tissue infections, was reported as a co-infecting microorganism during the 2009 A H1N1 influenza pandemic. We report a 65-year-old male patient who evolved with multifocal pneumonia and multiple organ failure with a fatal outcome. Influenza A H1N1 was detected by a polymerase chain reaction-based technique from a tracheal aspirate sample. S. pyogenes was identified by a rapid test from a nasopharyngeal sample and isolated afterwards from a positive blood culture. PMID:26436938

  4. Psr is involved in regulation of glucan production, and double deficiency of BrpA and Psr is lethal in Streptococcus mutans

    OpenAIRE

    Bitoun, Jacob P.; Liao, Sumei; McKey, Briggs A.; Yao, Xin; Fan, Yuwei; Abranches, Jacqueline; Beatty, Wandy L.; Wen, Zezhang T.

    2013-01-01

    Streptococcus mutans, the primary causative agent of dental caries, contains two paralogues of the LytR-CpsA-Psr family proteins encoded by brpA and psr, respectively. Previous studies have shown that BrpA plays an important role in cell envelope biogenesis/homeostasis and affects stress responses and biofilm formation by Strep. mutans, traits critical to cariogenicity of this bacterium. In this study, a Psr-deficient mutant, TW251, was constructed. Characterization of TW251 showed that defic...

  5. Characterization of salivary alpha-amylase binding to Streptococcus sanguis

    Energy Technology Data Exchange (ETDEWEB)

    Scannapieco, F.A.; Bergey, E.J.; Reddy, M.S.; Levine, M.J. (State Univ. of New York, Buffalo (USA))

    1989-09-01

    The purpose of this study was to identify the major salivary components which interact with oral bacteria and to determine the mechanism(s) responsible for their binding to the bacterial surface. Strains of Streptococcus sanguis, Streptococcus mitis, Streptococcus mutans, and Actinomyces viscosus were incubated for 2 h in freshly collected human submandibular-sublingual saliva (HSMSL) or parotid saliva (HPS), and bound salivary components were eluted with 2% sodium dodecyl sulfate. By sodium dodecyl sulfate-polyacrylamide gel electrophoresis and Western transfer, alpha-amylase was the prominent salivary component eluted from S. sanguis. Studies with {sup 125}I-labeled HSMSL or {sup 125}I-labeled HPS also demonstrated a component with an electrophoretic mobility identical to that of alpha-amylase which bound to S. sanguis. Purified alpha-amylase from human parotid saliva was radiolabeled and found to bind to strains of S. sanguis genotypes 1 and 3 and S. mitis genotype 2, but not to strains of other species of oral bacteria. Binding of ({sup 125}I)alpha-amylase to streptococci was saturable, calcium independent, and inhibitable by excess unlabeled alpha-amylases from a variety of sources, but not by secretory immunoglobulin A and the proline-rich glycoprotein from HPS. Reduced and alkylated alpha-amylase lost enzymatic and bacterial binding activities. Binding was inhibited by incubation with maltotriose, maltooligosaccharides, limit dextrins, and starch.

  6. In vitro activity of cefditoren and other comparators against Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis causing community-acquired respiratory tract infections in China.

    Science.gov (United States)

    Yang, Qiwen; Xu, Yingchun; Chen, Minjun; Wang, Hui; Sun, Hongli; Hu, Yunjian; Zhang, Rong; Duan, Qiong; Zhuo, Chao; Cao, Bin; Liu, Yong; Yu, Yunsong; Sun, Ziyong; Chu, Yunzhuo

    2012-06-01

    The aim of this study was to evaluate the in vitro activity of cefditoren and comparators against Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis causing community-acquired respiratory tract infections (CARTIs). A total of 391 Streptococcus pneumoniae, 266 H. influenzae, and 76 M. catarrhalis were isolated from 10 centers located at 6 cities in China from January 2009 to May 2010. The microdilution method was used to determine minimum inhibitory concentrations (MICs). The pneumococci comprised 189 (48.3%) penicillin susceptible, 129 (33.0%) penicillin intermediate, and 73 (18.7%) penicillin resistant. Moxifloxacin and levofloxacin showed the highest activity (99.2% and 97.7%, respectively) against Streptococcus pneumoniae, followed by parenteral penicillin G (95.7%), cefditoren (83.1%) and amoxicillin-clavulanic acid (79.3%). Among the 266 H. influenzae isolates, 26 (9.8%) were ampicillin-resistant ?-lactamase-producing strains and 24 (9.0%) were ampicillin-resistant ?-lactamase-nonproducing strains (BLNAR). Most of antimicrobial agents demonstrated good activity (>97% susceptibility) against H. influenzae except ampicillin, cefuroxime, and cefaclor, which showed relatively lower activity (81.2%, 88.7%, and 88%, respectively). Cefditoren showed excellent activity with the lowest MIC(50) and MIC(90) (?0.016/0.064 ?g/mL) among all tested drugs, which is independent of ?-lactamase production or ampicillin resistance. Cefditoren at a concentration of 0.5 ?g/mL inhibited all BLNAR strains. Seventy of 76 isolates of M. catarrhalis produced ?-lactamase. Cefditoren also showed excellent activity with MIC(90) of 0.064 ?g/mL against ?-lactamase-nonproducing strains and 0.5 ?g/mL against ?-lactamase-producing strains. In conclusion, the excellent intrinsic activity of cefditoren suggests that it may be a good choice for the treatment of CARTIs caused by Streptococcus pneumoniae, H. influenzae, and M. catarrhalis in China, while the activity should be closely monitored. PMID:22521692

  7. Perfil epidemiológico de las infecciones invasivas por Streptococcus pneumoniae: epidemiological profile / Invasive streptococcus pneumoniae

    Scientific Electronic Library Online (English)

    Julia, Bakir; Angela S., de Gentile; Gabriela, López Holtmann; Adriana, Procopio; Miryam, Vázquez.

    2003-01-01

    Full Text Available Introducción. Streptococcus pneumoniae (Sp) causa enfermedades invasivas de alta morbimortalidad, registrándose en la última década un aumento de la resistencia antibiótica. Material y métodos. Con el objetivo de estudiar la epidemiología del Sp, su susceptibilidad antibiótica y los factores de ries [...] go de resistencia a penicilina (RP), se evaluaron en forma prospectiva 274 pacientes con infecciones invasivas por Sp internados en el HNRG entre 1993 y 1999, inclusive. La mediana de edad fue de 21,5 meses (rango 1-180), la relación varón/mujer fue de 1,7:1; 11,8% eran desnutridos de II-III grado; 52,6% tenía enfermedad de base (respiratoria crónica o recidivante, 38,9%). A partir del aislamiento bacteriológico de Sp se realizó el seguimiento clínico-epidemiológico del paciente. Resultados. De 293 presentaciones clínicas, la más frecuente fue neumonía (64,2%), siguiendo meningitis (11,6%), sepsis/bacteriemia (10,9%), peritonitis (7,8%) y 16 pacientes presentaron formas asociadas. El Sp se recuperó de 325 materiales de cultivo: sangre, 55,1 %; líquido pleural, 27,1%; LCR, 9,2%; líquido peritoneal, 5,5% y otros, 3,1%. La RP global fue: 31,8% (87/274), con 17,9% resistencia (R) alta, observándose diferencias en la distribución anual. El 65,5% (57/87) de las cepas RP también lo eran a cefalosporinas de tercera generación (C3aG). Los factores de riesgo de infección por SpRP fueron: infección intrahospitalaria (RR 2,72; 2,00-3,69), tratamiento previo con ß lactámicos (RR 2,61; 1,91-3,55), neumonía (RR 2,06; 1,32-3,22), edad Abstract in english Introduction. Streptococcus pneumoniae (Sp) is a main cause of morbidity and mortality in children, and the increasing rates of drug resistant strains have been reported. The objectives of this study were to determine the epidemiology of invasive pneumococcal infections and the risk factors of Sp pe [...] nicillin resistance (PR). Material & methods. Two hundred seventy four children with invasive pneumococcal infections hospitalized in a children hospital, in the 1993-1999 period; the median age was 21.5 montlis (1 month-18 years), the male to female ratio was 1.7:1. Fifty two percent of cases reported an underlying disease. Results. The most frequent diseases were: pneumonia 64.2%, meningitis 11.6%, sepsislbacteriemia 10.9%, peritonitis 7.8%. Sp was recovered in 325 samples: blood in 55.1 %, pleural fluid 27.1 %, cerebrospinal fluid (CSF) 9.2%, peritoneal fluid 5.5% and other fluids obtained by puncture 3.1%. PR rate was 31.8% (87/274), 17.9% were highly resistant. Différences in the annual distribution was observed. 65.5% from PR strains were resistant to third generation cephalosporms too. PR was associated with: previous beta-lactam antibiotics therapy (RR 2.61; 1.91-3.55); nosocomial infection (RR 2.72; 2.00-3.69), pneumonia (RR 2.06; 1.32-3.22), and age under two years (RR 1.72; 1.182.49). Results from multivariate logistic regression analysis of binary predictors ofPR were: previous beta-Iactam antibiotics therapy (p=0,0003), nosocomial infection (p=0.0019) and pneumonia (p=0.0445). Mortality was 6.2% (17/274) without correlation with PR. Conclusion. These findings suggest the need for a continuous surveillance, control of drug resistant pneumococci and vaccination with an effective vaccine among high-risk patients.

  8. Autolisis de Streptococcus pneumoniae en hemocultivos Autolysis of Streptococcus pneumoniae in blood cultures

    Directory of Open Access Journals (Sweden)

    Hugo Edgardo Villar

    2005-06-01

    Full Text Available El proceso de autolisis de Streptococcus pneumoniae en medios líquidos puede ocasionar problemas en muestras de hemocultivos impidiendo su recuperación y, por lo tanto, el diagnóstico microbiológico, así como el estudio de sensibilidad a los antimicrobianos. El objetivo de este trabajo fue revisar la frecuencia de este fenómeno en muestras clínicas y determinar las mejores condiciones de detección para este germen en los sistemas automatizados. Fueron incluidos todos los pacientes con diagnóstico de neumonía y hemocultivos positivos por S. pneumoniae y pacientes con diagnóstico de neumonía, botellas positivas y subcultivos negativos. Se evaluó el tipo de botella empleada, tiempo de detección, tiempo de demora en subcultivar las botellas y recuperación del germen. El procesamiento de las botellas, identificación del microorganismo y el estudio de sensibilidad a los antibióticos se realizaron según el protocolo habitual del laboratorio. Se evaluaron 110 botellas distribuidas de la siguiente manera: 104 FAN aerobias y 6 FAN anaerobias pertenecientes a 51 pacientes. Se obtuvo señal de positividad en 96 FAN aerobias (92,3% y en 2 FAN anaerobias (33,3%. Todas las botellas positivas fueron detectadas en las primeras 26 h de incubación con una media de 11 h. En 38 de 51 pacientes (74,5% se recuperó S. pneumoniae en los subcultivos, mientras que en 13 (25,5% no se obtuvo desarrollo. La pérdida de viabilidad en estos casos se correlacionó con la demora en subcultivar las botellas positivas. La recuperación del germen fue del 100, 78,9 y 25% cuando la demora en subcultivar fue 14 h respectivamente. Se concluye que la utilización de botellas FAN aerobias permitió una adecuada recuperación de S. pneumoniae. Aquellos laboratorios que no poseen un servicio de guardia de Bacteriología podrían perder un porcentaje significativo de aislamientos de S. pneumoniae debido a fenómenos de autolisis. A fin de evitar este problema se recomienda implementar un sistema de vigilancia cada 7 h con descarga y subcultivo de botellas positivas.Spontaneous autolysis of Streptococcus pneumoniae in blood cultures causes a serious problem. Clinically relevant microorganisms are not detected and antimicrobial susceptibility testing cannot be performed. The aim of this study was to review the frequency of spontaneous autolysis in blood cultures and to analyze the detection and isolation of S. pneumoniae from blood cultures. Patients with clinically diagnosed pneumonia and positive blood cultures were included. Another group of patients with pneumonia, positive blood culture but negative subcultures was also included. Type of bottle, time of detection and recovery of S. pneumoniae in subcultures were recorded. All bottles were processed according to the manufacturer´s instructions. A total of 110 bottles from 51 patients were evaluated. Out of 104 FAN aerobic bottles, 96 (92.3% were positive. Out of 6 FAN anaerobic bottles only 2 (33.3% were positive. Mean time detection was 11 hours and all positive bottles were detected after 26 hours of incubation. S. pneumoniae was recovered in subcultures in 38 of 51 patients (74.5%. Loss of viability associated to autolysis was detected in 13 patients (25.5%. Loss of viability was related to delay in removal of positive bottles from incubator. The recovery of microorganisms was 100, 78.9 and 25% when the time of delay was 14 h respectively. Detection of S. pneumoniae was more frequent in FAN aerobic bottles. Isolates clinically significative of S. pneumoniae cannot be recovered if positive bottles remain inside incubator more than 7 hs. Microbiology laboratories should have personnel to remove positive bottles during the night and at weekends.

  9. Autolisis de Streptococcus pneumoniae en hemocultivos / Autolysis of Streptococcus pneumoniae in blood cultures

    Scientific Electronic Library Online (English)

    Hugo Edgardo, Villar; Liliana María, Longo; Gustavo Jorge, Laurino; Adriana, Vicente; Marisa Estela, Gutiérrez; Marta, Hoffman.

    2005-06-01

    Full Text Available El proceso de autolisis de Streptococcus pneumoniae en medios líquidos puede ocasionar problemas en muestras de hemocultivos impidiendo su recuperación y, por lo tanto, el diagnóstico microbiológico, así como el estudio de sensibilidad a los antimicrobianos. El objetivo de este trabajo fue revisar l [...] a frecuencia de este fenómeno en muestras clínicas y determinar las mejores condiciones de detección para este germen en los sistemas automatizados. Fueron incluidos todos los pacientes con diagnóstico de neumonía y hemocultivos positivos por S. pneumoniae y pacientes con diagnóstico de neumonía, botellas positivas y subcultivos negativos. Se evaluó el tipo de botella empleada, tiempo de detección, tiempo de demora en subcultivar las botellas y recuperación del germen. El procesamiento de las botellas, identificación del microorganismo y el estudio de sensibilidad a los antibióticos se realizaron según el protocolo habitual del laboratorio. Se evaluaron 110 botellas distribuidas de la siguiente manera: 104 FAN aerobias y 6 FAN anaerobias pertenecientes a 51 pacientes. Se obtuvo señal de positividad en 96 FAN aerobias (92,3%) y en 2 FAN anaerobias (33,3%). Todas las botellas positivas fueron detectadas en las primeras 26 h de incubación con una media de 11 h. En 38 de 51 pacientes (74,5%) se recuperó S. pneumoniae en los subcultivos, mientras que en 13 (25,5%) no se obtuvo desarrollo. La pérdida de viabilidad en estos casos se correlacionó con la demora en subcultivar las botellas positivas. La recuperación del germen fue del 100, 78,9 y 25% cuando la demora en subcultivar fue 14 h respectivamente. Se concluye que la utilización de botellas FAN aerobias permitió una adecuada recuperación de S. pneumoniae. Aquellos laboratorios que no poseen un servicio de guardia de Bacteriología podrían perder un porcentaje significativo de aislamientos de S. pneumoniae debido a fenómenos de autolisis. A fin de evitar este problema se recomienda implementar un sistema de vigilancia cada 7 h con descarga y subcultivo de botellas positivas. Abstract in english Spontaneous autolysis of Streptococcus pneumoniae in blood cultures causes a serious problem. Clinically relevant microorganisms are not detected and antimicrobial susceptibility testing cannot be performed. The aim of this study was to review the frequency of spontaneous autolysis in blood cultures [...] and to analyze the detection and isolation of S. pneumoniae from blood cultures. Patients with clinically diagnosed pneumonia and positive blood cultures were included. Another group of patients with pneumonia, positive blood culture but negative subcultures was also included. Type of bottle, time of detection and recovery of S. pneumoniae in subcultures were recorded. All bottles were processed according to the manufacturer´s instructions. A total of 110 bottles from 51 patients were evaluated. Out of 104 FAN aerobic bottles, 96 (92.3%) were positive. Out of 6 FAN anaerobic bottles only 2 (33.3%) were positive. Mean time detection was 11 hours and all positive bottles were detected after 26 hours of incubation. S. pneumoniae was recovered in subcultures in 38 of 51 patients (74.5%). Loss of viability associated to autolysis was detected in 13 patients (25.5%). Loss of viability was related to delay in removal of positive bottles from incubator. The recovery of microorganisms was 100, 78.9 and 25% when the time of delay was 14 h respectively. Detection of S. pneumoniae was more frequent in FAN aerobic bottles. Isolates clinically significative of S. pneumoniae cannot be recovered if positive bottles remain inside incubator more than 7 hs. Microbiology laboratories should have personnel to remove positive bottles during the night and at weekends.

  10. Aspectos clínico-epidemiológicos de las infecciones por Streptococcus pyogenes en el período neonatal Clinical and epidemiological aspects of the infections caused by Streptococcus pyogenes in the neonatal period

    Directory of Open Access Journals (Sweden)

    Manuel Díaz Alvarez

    2008-03-01

    Full Text Available INTRODUCCIÓN. El objetivo de la presente investigación fue describir las características clínicas y epidemiológicas de la infección por Estreptococo del grupo A en los recién nacidos egresados de hospitales maternos. MÉTODOS. Se realizó un estudio descriptivo, que incluyó a recién nacidos consecutivos, quienes tuvieron infecciones por estreptococos del grupo A y que estuvieron ingresados en el servicio de neonatología del Hospital Pediátrico Universitario «Juan M. Márquez» entre 1992 y el 2005. Se procesaron y analizaron distintas variables clínicas y epidemiológicas con cálculo de tasas de incidencia y letalidad. RESULTADOS. Se registraron 20 recién nacidos con infección por estreptococos del grupo A, lo cual representó una tasa promedio anual de 0,2 cada 100 ingresos. Esta infección muestra una incidencia con tendencia significativa a disminuir en los últimos años. Según la clasificación utilizada, todas las infecciones fueron de inicio tardío y, de acuerdo al origen, predominaron las adquiridas en la comunidad (95,0 %. La infección de tejidos blandos fue la forma clínica más frecuente (10 de 20; 50 % y cursó con bacteriemia. Los aislamientos de estreptococos del grupo A tuvieron un 100 % de sensibilidad ante los betalactámicos. Hubo un solo paciente fallecido, afecto de meningitis, lo cual significó una tasa de letalidad del 5,0 %. CONCLUSIONES. El estreptococo del grupo A es un agente causal de infecciones que afectan al recién nacido, fundamentalmente en el ambiente comunitario. Estas infecciones pueden ser letales en algunos pacientes con infección del sistema nervioso central, a pesar del patrón de elevada susceptibilidad a los betalactámicos.INTRODUCTION. The objective of the present investigation was to describe the clinical and epidemiological characteristics of the infection caused by group A Streptococcus in the newborn infants discharged from maternal hospitals. METHODS. A descriptive study that included consecutive newborn infants who had infections caused by group A Streptococcus and that were admitted in the neonatology service of "Juan M. Márquez" Pediatric Teaching Hospital between 1992 and 2005 was carried out. Different clinical and epidemiological variables were processed and analyzed by calculating the incidence and lethality rates. RESULTS. 20 newborn infants with infection caused by group A Streptococcus were registered, accounting for an annual average rate of 0.2 per 100 admissions. This infection shows an incidence with a significant trend to decrease in the last years. According to the classification used, all the infections had a late onset, and regarding their origin those acquired in the community prevailed (95.0 %. The infection of the soft tissues was the most common clinical form (10 of 20; 50 % and evolved with bacteremia. The isolations of group A Streptococcus has 100 % of sensitivity to betalactamics. Only one patient affected with meningitis died, which represented a lethality rate of 5.0 %. CONCLUSIONS. The group A Streptococcus is an agent causing infections that affect the newborn infant, mainly in the community environment. These infections may be lethal in some patients with infection of the central nervous system, in spite of the pattern of elevated susceptibility to betalactamics.

  11. Aspectos clínico-epidemiológicos de las infecciones por Streptococcus pyogenes en el período neonatal / Clinical and epidemiological aspects of the infections caused by Streptococcus pyogenes in the neonatal period

    Scientific Electronic Library Online (English)

    Manuel, Díaz Alvarez; Bárbara, Acosta Batista; Daniel, Claver Isás; María Teresa, Fernández de la Paz; Alicia, Martínez Izquierdo.

    2008-03-01

    Full Text Available INTRODUCCIÓN. El objetivo de la presente investigación fue describir las características clínicas y epidemiológicas de la infección por Estreptococo del grupo A en los recién nacidos egresados de hospitales maternos. MÉTODOS. Se realizó un estudio descriptivo, que incluyó a recién nacidos consecutiv [...] os, quienes tuvieron infecciones por estreptococos del grupo A y que estuvieron ingresados en el servicio de neonatología del Hospital Pediátrico Universitario «Juan M. Márquez» entre 1992 y el 2005. Se procesaron y analizaron distintas variables clínicas y epidemiológicas con cálculo de tasas de incidencia y letalidad. RESULTADOS. Se registraron 20 recién nacidos con infección por estreptococos del grupo A, lo cual representó una tasa promedio anual de 0,2 cada 100 ingresos. Esta infección muestra una incidencia con tendencia significativa a disminuir en los últimos años. Según la clasificación utilizada, todas las infecciones fueron de inicio tardío y, de acuerdo al origen, predominaron las adquiridas en la comunidad (95,0 %). La infección de tejidos blandos fue la forma clínica más frecuente (10 de 20; 50 %) y cursó con bacteriemia. Los aislamientos de estreptococos del grupo A tuvieron un 100 % de sensibilidad ante los betalactámicos. Hubo un solo paciente fallecido, afecto de meningitis, lo cual significó una tasa de letalidad del 5,0 %. CONCLUSIONES. El estreptococo del grupo A es un agente causal de infecciones que afectan al recién nacido, fundamentalmente en el ambiente comunitario. Estas infecciones pueden ser letales en algunos pacientes con infección del sistema nervioso central, a pesar del patrón de elevada susceptibilidad a los betalactámicos. Abstract in english INTRODUCTION. The objective of the present investigation was to describe the clinical and epidemiological characteristics of the infection caused by group A Streptococcus in the newborn infants discharged from maternal hospitals. METHODS. A descriptive study that included consecutive newborn infants [...] who had infections caused by group A Streptococcus and that were admitted in the neonatology service of "Juan M. Márquez" Pediatric Teaching Hospital between 1992 and 2005 was carried out. Different clinical and epidemiological variables were processed and analyzed by calculating the incidence and lethality rates. RESULTS. 20 newborn infants with infection caused by group A Streptococcus were registered, accounting for an annual average rate of 0.2 per 100 admissions. This infection shows an incidence with a significant trend to decrease in the last years. According to the classification used, all the infections had a late onset, and regarding their origin those acquired in the community prevailed (95.0 %). The infection of the soft tissues was the most common clinical form (10 of 20; 50 %) and evolved with bacteremia. The isolations of group A Streptococcus has 100 % of sensitivity to betalactamics. Only one patient affected with meningitis died, which represented a lethality rate of 5.0 %. CONCLUSIONS. The group A Streptococcus is an agent causing infections that affect the newborn infant, mainly in the community environment. These infections may be lethal in some patients with infection of the central nervous system, in spite of the pattern of elevated susceptibility to betalactamics.

  12. Evaluation of Three Commercial Broth Media for Pigment Detection and Identification of a Group B Streptococcus (Streptococcus agalactiae)?

    OpenAIRE

    Carvalho, Maria da Glória; Facklam, Richard; Jackson, Delois; Beall, Bernard; McGee, Lesley

    2009-01-01

    Detection of group B Streptococcus (GBS) strains at various bacterial concentrations was evaluated using three pigment-producing broth media. At 103 CFU/ml, StrepB carrot broth (SBCB), Granada instant liquid biphasic (IGLB), and Northeast Laboratory GBS screening medium (NEL-GBS) showed 100% detection, but at the lower bacterial counts, SBCB and IGLB were more sensitive than NEL-GBS after 24 h.

  13. Impacto de Streptococcus pneumoniae en las neumonías del niño latinoamericano Impact of Streptococcus pneumoniae in pneumonias of Latin American children

    OpenAIRE

    María Hortal; Raúl Ruvinsky; Alicia Rossi; Clara I. Agudelo; Elizabeth Castañeda; Cristina Brandileone; Teresa Camou; Rosario Palacio; Gabriela Echaniz; José L. Di Fabio

    2000-01-01

    La neumonía adquirida en la comunidad es una de las principales causas de morbilidad y mortalidad en la infancia. Estudios realizados en países en desarrollo indican que los cuadros de neumonía más graves se asocian a causas bacterianas, con predominio de Streptococcus pneumoniae, seguido por Haemophilus influenzae tipo b. El manejo de esas infecciones en los menores de 2 años se ve dificultado por la carencia de vacunas apropiadas y por la disminución de la susceptibilidad de S. pneumoniae a...

  14. Impact of immunization against SpyCEP during invasive disease with two streptococcal species: Streptococcus pyogenes and Streptococcus equi

    OpenAIRE

    Turner, Claire E; Kurupati, Prathiba; Wiles, Siouxsie; Edwards, Robert J; Sriskandan, Shiranee

    2009-01-01

    Currently there is no licensed vaccine against the human pathogen Streptococcus pyogenes. The highly conserved IL-8 cleaving S. pyogenes cell envelope proteinase SpyCEP is surface expressed and is a potential vaccine candidate. A recombinant N-terminal part of SpyCEP (CEP) was expressed and purified. AntiCEP antibodies were found to neutralize the IL-8 cleaving activity of SpyCEP. CEP-immunized mice had reduced bacterial dissemination from focal S. pyogenes intramuscular infection and intrana...

  15. Meningoencefalitis por Streptococcus pneumoniae resistente: reporte de un caso

    Scientific Electronic Library Online (English)

    Olga María, Rodríguez Fernández; Odalis, Ferrer Morell; Yuneixy, Pérez Morales; Alexis, Sanchén Casas.

    2011-12-01

    Full Text Available Introducción: Streptococcus pneumoniae es una bacteria que reside en el aparato respiratorio superior de las personas saludables, pero resulta una infección cuando alcanza localizaciones normalmente estériles, tales como el aparato respiratorio inferior, sistema circulatorio, y sistema nervioso cent [...] ral. Esto ocurre en personas inmunodeprimidas, por diferentes causas. Objetivo: destacar la virulencia de Streptococcus pneumoniae drogo resistente. Caso clínico: niña que llega al hospital por presentar un proceso respiratorio, de varios días de evolución, con fiebre y rinorrea. Ingresó en la sala de Infecciones Respiratorias. Comenzó con deshidratación y somnolencia, por lo que se le realizó una segunda punción lumbar, que resultó con salida de líquido cefalorraquídeo, purulento y presencia de 202 células a predominio de polimorfonucleares, glucosa disminuida, aumento de las proteínas, y Pandy xxxx. La niña se agrava y presenta signos de intenso edema cerebral, con fontanela abombada. Se trató con antimicrobianos como la vancomicina y el ceftriaxone, por varios días. En el laboratorio de Microbiología se confirmó el crecimiento de Streptococccus pneumoniae sensible al meronem que pasa a reemplazar al ceftriaxone. La paciente salió paulatinamente de su gravedad hasta que fue dada de alta con seguimiento y rehabilitación, por presentar secuelas. Conclusiones: este patógeno tan peligroso con sus atributos de virulencia y su elevada resistencia a los antimicrobianos, constituye un fenómeno emergente. Abstract in english Background: Streptococcus pneumoniae is the bacterium that resides in the upper respiratory system of healthy people, but turns into infection, when it reaches usually sterile locations such as the lower respiratory system, the circulatory, and the central nervous systems. This occurs in immunocompr [...] omised persons, for different reasons. Objective: to point out the Streptococcus pneumoniae's virulence resistant to drugs. Clinical case: it is presented a girl who arrived at the hospital with a respiratory process, of several days of evolution with fever and rhinorrhea, the girl was admitted in the respiratory ward. She started with dehydratation and sleepiness; a second lumbar puncture was made, a purulent cerebrospinal fluid and the presence of 202 cells, most of them polymorphonuclear, with decreased glucose and a protein augmentation, with Pandy xxxx, was observed. The girl gets worse and presented an intense cerebral edema, with enlarged fontanel, she was treated with antimicrobials such as vancomycin and ceftriaxone for several days. The microbiology laboratory confirmed the growth of Streptococcus pneumoniae sensitive to meronem and replaces ceftriaxone. Result: the patient gradually left his gravity until that she was discharged from hospital with follow-up and rehabilitation, by sequels. Conclusions: this dangerous pathogen with their attributes of virulence and its high resistance to antimicrobials is an emerging phenomenon.

  16. Meningitis bacteriana aguda por Streptococcus suis en criadores de cerdos: comunicación de los primeros dos casos en Chile / Streptococcus suis meningitis in pig farmers: report of first two cases in Chile

    Scientific Electronic Library Online (English)

    Erica, Koch; Gino, Fuentes; Rodrigo, Carvajal; Ricardo, Palma; Verónica, Aguirre; Carolina, Cruz; Ruby, Henríquez; Mario, Calvo.

    2013-10-01

    Full Text Available La infección humana por Streptococcus suis es una zoonosis con riesgo ocupacional conocido, siendo la meningitis aguda su manifestación clínica más frecuente. Se presentan los dos primeros casos en Chile. Primer caso: Mujer de 54 años con un cuadro de cefalea y vómitos, confusión y signos meníngeos. [...] Evolucionó con un shock séptico. Segundo caso: Varón de 48 años, refirió cefalea y vómitos. Presentó signos meníngeos al examen físico. En ambos casos en la tinción de Gram de líquido cefalorraquídeo (LCR) se observaron cocáceas grampositivas. Fueron tratados con ceftriaxona y dexametasona. El cultivo de LCR fue positivo en ambos casos para S. suis serotipo 2. En los dos pacientes la evolución clínica fue favorable, sin alteraciones neurológicas al alta. En ambos casos se obtuvo en forma retrospectiva el antecedente de realizar labores de crianza de ganado porcino. Se destaca la importancia de investigar los antecedentes epidemiológicos para sospechar este agente etiológico en meningitis aguda. Se debe considerar el riesgo ocupacional en una posible infección por este patógeno humano emergente y educar a la población en riesgo sobre medidas preventivas simples. Abstract in english Human infection by Streptococcus suis is a zoonosis with a known occupational risk. Meningitis is its most frequent clinical manifestation. We present the first two cases in Chile. First case: 54-year-old female patient, pig-farmer. She presented headache, vomiting, confusion and meningismus. She pr [...] esented septic shock. Second case: 48-year-old male patient, also pig farmer, presented headache, vomiting and meningismus. A Gram's staining of cerebrospinal fluid (CSF) showed gram-positive cocci in both cases. Ceftriaxone and dexamethasone treatment was administered. The CSF cultures were positive for Streptococcus suis serotype 2. The patients experienced a good outcome, without neurological sequelae at the time of discharge. It is considerable to evaluate epidemiologic factors in order to suspect this etiological agent in cases of meningitis. These cases enhance the need of heighten awareness of potential for occupational exposure and infection by this emerging human pathogen. Educating population at risk about simple preventive measures must be considered.

  17. Trading Agents

    CERN Document Server

    Wellman, Michael

    2011-01-01

    Automated trading in electronic markets is one of the most common and consequential applications of autonomous software agents. Design of effective trading strategies requires thorough understanding of how market mechanisms operate, and appreciation of strategic issues that commonly manifest in trading scenarios. Drawing on research in auction theory and artificial intelligence, this book presents core principles of strategic reasoning that apply to market situations. The author illustrates trading strategy choices through examples of concrete market environments, such as eBay, as well as abst

  18. Group B streptococcus cystitis presenting in a diabetic patient with a massive abdominopelvic abscess: a case report

    OpenAIRE

    Ulett Kimberly B; Shuemaker Jennifer H; Benjamin William H; Tan Chee K; Ulett Glen C

    2012-01-01

    Abstract Introduction Streptococcus agalactiae or group B streptococcus is a Gram-positive pathogen that is typically associated with neonatal disease and infection in pregnant women. Group B streptococcus also causes invasive infections in non-pregnant adults including urinary tract infections. The spectrum of urinary tract infections caused by group B streptococcus includes cystitis, pyelonephritis, urosepsis and asymptomatic bacteriuria, which is particularly common among elderly individua...

  19. Antimicrobial agents for community-acquired respiratory tract infections.

    Science.gov (United States)

    Barry, A L

    1995-01-01

    Chemotherapy of community-acquired respiratory tract infections was reviewed from a microbiological perspective. The current worldwide spread of penicillin-resistant Streptococcus pneumoniae and of ampicillin-resistant Haemophilus influenzae has required a reassessment of the antimicrobial agents being used for empiric therapy. In vitro data with different orally administered antibiotics were reviewed in order to identify any deficiencies in their spectra of activity against four common respiratory tract pathogens. Cefixime, cefuroxime axetil, cefprozil, amoxicillin-clavulanic acid and trimethoprim-sulfamethoxazole were active against all four species other than penicillin-resistant pneumococci. PMID:8537133

  20. Non-infectivity of Cattle Streptococcus agalactiae in Nile Tilapia, Oreochromis niloticus and Channel Catfish, Ictalurus punctatus

    Science.gov (United States)

    Streptococcus agalactiae is classified as a Lancefield’s group B Streptococcus (GBS). It is the causative bacterium of streptococcosis that is responsible for severe economic losses in wild and cultured fish, worldwide. Streptococcus agalactiae also causes bovine mastitis. Only limited comparativ...

  1. Significance of Gram's Stain in Rapid Intrapartum Screening for Maternal Carriership of Group B Streptococcus

    OpenAIRE

    Adriaanse, Albert H; Muytjens, Harry L.; Kollée, Louis A A; Nijhuis, Jan G.; Hoogkamp-Korstanje, Jacomina A. A.

    1995-01-01

    Objective: Group B streptococcus (GBS, Streptococcus agalactiae) is an important cause of neonatal sepsis. Prevention is possible by intrapartum screening for maternal GBS carriership and antimicrobial treatment of colonized women with risk factors during labor. The conflicting results of diagnostic performance are reported both for the newly developed rapid GBS antigen tests and Gram's stain.

  2. Sulfonamide inhibition study of the ?-class carbonic anhydrase from the caries producing pathogen Streptococcus mutans.

    Science.gov (United States)

    Dedeoglu, Nurcan; DeLuca, Viviana; Isik, Semra; Yildirim, Hatice; Kockar, Feray; Capasso, Clemente; Supuran, Claudiu T

    2015-06-01

    Streptococcus mutans, the oral pathogenic bacterium provoking dental caries formation, encodes for a ?-class carbonic anhydrase (CA, EC 4.2.1.1), SmuCA. This enzyme was cloned, characterized and investigated for its inhibition profile with the major class of CA inhibitors, the primary sulfonamides. SmuCA has a good catalytic activity for the CO2 hydration reaction, with a kcat of 4.2×10(5) s(-1) and kcat/Km of 5.8×10(7) M(-1)×s(-1), and is efficiently inhibited by most sulfonamides (KIs of 246 nM-13.5 ?M). The best SmuCA inhibitors were bromosulfanilamide, deacetylated acetazolamide, 4-hydroxymethylbenzenesulfonamide, a pyrimidine-substituted sulfanilamide derivative, aminobenzolamide and compounds structurally similar to it, as well as acetazolamide, methazolamide, indisulam and valdecoxib. These compounds showed inhibition constants ranging between 246 and 468 nM. Identification of effective inhibitors of this enzyme may lead to pharmacological tools useful for understanding the role of S. mutans CAs in dental caries formation, and eventually the development of pharmacological agents with a new mechanism of antibacterial action. PMID:25913199

  3. Antiadhesion and antibiofilm activities of high molecular weight coffee components against Streptococcus mutans.

    Science.gov (United States)

    Stauder, Monica; Papetti, Adele; Mascherpa, Dora; Schito, Anna Maria; Gazzani, Gabriella; Pruzzo, Carla; Daglia, Maria

    2010-11-24

    In previous studies we demonstrated that green and roasted coffee contains low molecular weight (LMW) compounds capable of inhibiting the ability of Streptococcus mutans, the major causative agent of human dental caries, to adhere to hydroxyapatite (HA) beads. This study addressed the ability of the whole high molecular weight coffee fraction (cHMW) and of its melanoidin and non-melanoidin components (GFC1-5), applied at concentrations that occur in coffee beverages, to (i) inhibit S. mutans growth; (ii) affect S. mutans sucrose-dependent adhesion to and detachment from saliva-coated HA beads (sHA); and (iii) inhibit biofilm development on microtiter plates. The results indicated that only cHMW is endowed with antimicrobial activity. The cHMW fraction and each of the five GFC components inhibited S. mutans adhesion, the strongest effect being exerted by cHMW (91%) and GFC1 (88%). S. mutans detachment from sHA was four times greater (?20%) with cHMW and the GFC1 and GFC4 melanoidins than with controls. Finally, biofilm production by S. mutans was completely abolished by cHMW and was reduced by 20% by the melanoidin components GFC2 and GFC4 and by the non-melanoidin component GFC5 compared with controls. Altogether these findings show that coffee beverage contains both LMW compounds and HMW melanoidin and non-melanoidin components with a strong ability to interfere in vitro with the S. mutans traits relevant for cariogenesis. PMID:21038921

  4. Crystallization of dihydrodipicolinate synthase from a clinical isolate of Streptococcus pneumoniae

    International Nuclear Information System (INIS)

    The emergence of drug-resistant bacteria highlights the importance of identifying potential drug targets. Dihydrodipicolinate synthase (DHDPS) is a valid but as yet unexploited antimicrobial target that functions in the biosynthesis of (S)-lysine. In this study, the cloning, expression, purification, crystallization and preliminary X-ray diffraction analysis of DHDPS from S. pneumoniae are described. Dihydrodipicolinate synthase (DHDPS; EC 4.2.1.52) catalyzes the rate-limiting step in the (S)-lysine biosynthesis pathway of bacteria and plants. Here, the cloning of the DHDPS gene from a clinical isolate of Streptococcus pneumoniae (OXC141 strain) and the strategy used to express, purify and crystallize the recombinant enzyme are described. Diffracting crystals were grown in high-molecular-weight PEG precipitants using the hanging-drop vapour-diffusion method. The best crystal, from which data were collected, diffracted to beyond 2.0 Å resolution. Initially, the crystals were thought to belong to space group P42212, with unit-cell parameters a = 105.5, b = 105.5, c = 62.4 Å. However, the R factors remained high following initial processing of the data. It was subsequently shown that the data set was twinned and it was thus reprocessed in space group P2, resulting in a significant reduction in the R factors. Determination of the structure will provide insight into the design of novel antimicrobial agents targeting this important enzyme from S. pneumoniae

  5. Serotype distribution and antimicrobial resistance of Streptococcus pneumoniae causing noninvasive diseases in a Children's Hospital, Shanghai

    Scientific Electronic Library Online (English)

    Fen, Pan; Lizhong, Han; Jing, Kong; Chun, Wang; Huihong, Qin; Shuzhen, Xiao; Junying, Zhu; Hong, Zhang.

    2015-04-01

    Full Text Available Background: Streptococcus pneumoniae, which cause noninvasive pneumococcal diseases, severely impair children's health. This study analyzed serotype distribution and antimicrobial resistance of S. pneumoniae from January 2012 to December 2012 in a Children's Hospital, Shanghai. Methods: A total of [...] 328 pneumococcal isolates were serotyped by multiplex sequential PCR and/or capsule-quellung reaction. The minimum inhibitory concentrations for 11 antimi- crobial agents were determined by broth microdilution method. Results: Among 328 strains, 19F (36.3%), 19A (13.4%), 6A (11.9%), 23F (11.0%), 14 (5.8%), 6B (5.2%), and 15B/C (4.3%) were the most common serotypes. The coverage rates of 7-, 10-, and 13-valent conjugate vaccines (PCV7, PCV10, and PCV13) were 58.2%, 58.2%, and 84.1%, respectively. Out of the isolates, 26 (7.9%) strains were penicillin resistant. Most of the strains displayed high resistance rate to macrolides (98.5% to erythromycin, 97.9% to azithromycin, and 97.0% to clindamycin). Conclusions: The potential coverage of PCV13 is higher than PCV7 and PCV10 because of the emergence of 19A and there should be long-term and systematic surveillance for non-vaccine serotypes.

  6. Antibacterial Activity of Propolis Supplemented-Chewing Candy Against Streptococcus mutans

    Directory of Open Access Journals (Sweden)

    AHMAD ENDANG ZAINAL HASAN

    2011-09-01

    Full Text Available Streptococcus mutans is considered to play a major etiological role in development of human dental plaque believed to related to dental caries, the most prevalent disease of the human oral cavity. The objectives of the present study were to formulate and produce propolis supplemented-chewing candy and to investigate its antibacterial activity against S. mutans. Propolis is a natural resinous bee-hive product thought to have antimicrobial, anti-inflammatory and immunostimulating activities. Propolis was extracted from hives of bees of Trigona spp. using ethanol. The extract was coated with maltodextrine and homogenized to generate propolis microparticles. The particles were introduced into chewing candy preparations for the production of propolis supplemented-chewing candy. The candy was then subjected to in vitro antibacterial assays to test its activity against S. mutans isolated from human dental plaque. Results showed that the ethanol extracted propolis of Trigona spp. bee-hives can be homogenized to form propolis microparticles. The propolis microparticles could be used as a supplement in the formulation of chewing candy preparations. The propolis supplemented-chewing candy showed antibacterial activity against S. mutans. The candy, therefore, has the potential to be used as an antiplaque agent for prevention of dental caries.

  7. Diagnosis of Streptococcus pneumoniae meningitis by polymerase chain reaction amplification of the gene for pneumolysin

    Directory of Open Access Journals (Sweden)

    Juliana de A Matos

    2006-08-01

    Full Text Available Diagnosis of bacterial meningitis has long been based on classical methods of Gram stain, serological tests, and culture of cerebrospinal fluid (CSF. The performance of these methods, especially culture and direct smear, is thwarted by failure to detect bacteria following administration of antimicrobial agents and reluctance to performance lumbar punctures at admission. Indeed, patients with meningitis frequently receive antibiotics orally or by injection before the diagnosis is suspected or established. Thus an alternative method has become necessary to help clinicians and epidemiologists to management and control of bacterial meningitis. We evaluate the application of a polymerase chain reaction-based (PCR assay for amplification of pneumolysin gene (ply to diagnosis of Streptococcus pneumoniae meningitis. The PCR assay sensitivity for CSF was 96% (95% confidence interval, CI, 90-99% compared to a sensitivity of 59% for culture (95% CI 49-69%, 66% for Gram stain (95% CI 56-74%, and 78% for latex agglutination test (95% CI 69-86%; PCR specificity was 100% (95% CI 83-100%. PCR results were available within 4 h of the start of the assay. This molecular approach proved to be reliable and useful to identify this bacterium compared with other classical laboratory methods for identification of bacterial meningitis pathogens.

  8. Evaluation of genotypic diversity of Streptococcus mutans using distinct arbitrary primers

    Scientific Electronic Library Online (English)

    Cínthia Pereira Machado, Tabchoury; Maria Clara K., Sousa; Rodrigo Alex, Arthur; Renata Oliveira, Mattos-Graner; Altair Antoninha, Del Bel Cury; Jaime Aparecido, Cury.

    2008-12-01

    Full Text Available Streptococcus mutans has been considered one of the main etiological agents of dental caries and the genotypic diversity rather than its salivary counts may be considered as a virulence factor of this bacterium. For genotyping with polymerase chain reaction (PCR) with arbitrary primers, several prim [...] ers have been used in order to improve complexity and specificity of amplicon patterns. Thus, the aim of this study was to evaluate the degree of agreement of genotypic identification among AP-PCR reactions performed with 5 distinct arbitrary primers of S. mutans isolated from saliva. Stimulated saliva was collected from 11 adult volunteers for isolation of S. mutans, and a total of 88 isolates were genotyped with arbitrary primers OPA 02, 03, 05, 13 and 18. Fourteen distinct genotypes were identified in the saliva samples. Most volunteers (9 out of 11) presented only one genotype. The results of the present study suggest that primers OPA 02, 03, 05 and 13 were suitable for genotypic identification of S. mutans isolates of saliva from adult volunteers.

  9. Conjugative transfer of resistance determinants among human and bovine Streptococcus agalactiae

    Scientific Electronic Library Online (English)

    Tatiana Castro Abreu, Pinto; Natália Silva, Costa; Ana Beatriz de Almeida, Corrêa; Ivi Cristina Menezes de, Oliveira; Marcos Correa de, Mattos; Alexandre Soares, Rosado; Leslie Claude, Benchetrit.

    2014-09-01

    Full Text Available Streptococcus agalactiae (GBS) is a major source of human perinatal diseases and bovine mastitis. Erythromycin (Ery) and tetracycline (Tet) are usually employed for preventing human and bovine infections although resistance to such agents has become common among GBS strains. Ery and Tet resistance g [...] enes are usually carried by conjugative transposons (CTns) belonging to the Tn916 family, but their presence and transferability among GBS strains have not been totally explored. Here we evaluated the presence of Tet resistance genes (tetM and tetO) and CTns among Ery-resistant (Ery-R) and Ery-susceptible (Ery-S) GBS strains isolated from human and bovine sources; and analyzed the ability for transferring resistance determinants between strains from both origins. Tet resistance and int-Tn genes were more common among Ery-R when compared to Ery-S isolates. Conjugative transfer of all resistance genes detected among the GBS strains included in this study (ermA, ermB, mef, tetM and tetO), in frequencies between 1.10-7 and 9.10-7, was possible from bovine donor strains to human recipient strain, but not the other way around. This is, to our knowledge, the first report of in vitro conjugation of Ery and Tet resistance genes among GBS strains recovered from different hosts.

  10. Evaluation of genotypic diversity of Streptococcus mutans using distinct arbitrary primers

    Directory of Open Access Journals (Sweden)

    Cínthia Pereira Machado Tabchoury

    2008-12-01

    Full Text Available Streptococcus mutans has been considered one of the main etiological agents of dental caries and the genotypic diversity rather than its salivary counts may be considered as a virulence factor of this bacterium. For genotyping with polymerase chain reaction (PCR with arbitrary primers, several primers have been used in order to improve complexity and specificity of amplicon patterns. Thus, the aim of this study was to evaluate the degree of agreement of genotypic identification among AP-PCR reactions performed with 5 distinct arbitrary primers of S. mutans isolated from saliva. Stimulated saliva was collected from 11 adult volunteers for isolation of S. mutans, and a total of 88 isolates were genotyped with arbitrary primers OPA 02, 03, 05, 13 and 18. Fourteen distinct genotypes were identified in the saliva samples. Most volunteers (9 out of 11 presented only one genotype. The results of the present study suggest that primers OPA 02, 03, 05 and 13 were suitable for genotypic identification of S. mutans isolates of saliva from adult volunteers.

  11. Phenotypic characterization of the foldase homologue PrsA in Streptococcus mutans.

    Science.gov (United States)

    Guo, L; Wu, T; Hu, W; He, X; Sharma, S; Webster, P; Gimzewski, J K; Zhou, X; Lux, R; Shi, W

    2013-04-01

    Streptococcus mutans is generally considered to be the principal etiological agent for dental caries. Many of the proteins necessary for its colonization of the oral cavity and pathogenesis are exported to the cell surface or the extracellular matrix, a process that requires the assistance of the export machineries. Bioinformatic analysis revealed that the S. mutans genome contains a prsA gene, whose counterparts in other gram-positive bacteria, including Bacillus and Lactococcus, encode functions involved in protein post-export. In this study, we constructed a PrsA-deficient derivative of S. mutans and demonstrated that the prsA mutant displayed an altered cell wall/membrane protein profile as well as cell-surface-related phenotypes, including auto-aggregation, increased surface hydrophobicity and abnormal biofilm formation. Further analysis revealed that the disruption of the prsA gene resulted in reduced insoluble glucan production by cell surface localized glucosyltransferases, and mutacin as well as cell surface-display of a heterologous expressed GFP fusion to the cell surface protein SpaP. Our study suggested that PrsA in S. mutans encodes functions similar to those identified in Bacillus, and so is likely to be involved in protein post-export. PMID:23241367

  12. Role of HtrA in surface protein expression and biofilm formation by Streptococcus mutans.

    Science.gov (United States)

    Biswas, Saswati; Biswas, Indranil

    2005-10-01

    The HtrA surface protease in gram-positive bacteria is involved in the processing and maturation of extracellular proteins and degradation of abnormal or misfolded proteins. Inactivation of htrA has been shown to affect the tolerance to thermal and environmental stress and to reduce virulence. We found that inactivation of Streptococcus mutans htrA by gene-replacement also resulted in a reduced ability to withstand exposure to low and high temperatures, low pH, and oxidative and DNA damaging agents. The htrA mutation affected surface expression of several extracellular proteins including glucan-binding protein B (GbpB), glucosyltransferases, and fructosyltransferase. In addition, htrA mutation also altered the surface expression of enolase and glyceraldehyde-3-phosphate dehydrogenease, two glycolytic enzymes that are known to be present on the streptococcal cell surface. As expected, microscopic analysis of in vitro grown biofilm structure revealed that the htrA deficient biofilms adopted a much more granular patchy appearance, rather than the relatively smooth confluent layer normally seen in the wild type. These results suggest that HtrA plays an important role in the biogenesis of extracellular proteins including surface associated glycolytic enzymes and in biofilm formation of S. mutans. PMID:16177372

  13. Regulation of the glucosyltransferase (gtfBC) operon by CovR in Streptococcus mutans.

    Science.gov (United States)

    Biswas, Saswati; Biswas, Indranil

    2006-02-01

    Streptococcus mutans is an important etiological agent of dental caries in humans. The extracellular polysaccharides synthesized by cell-associated glucosyltransferases (encoded by gtfBC) from sucrose have been recognized as one of the important virulence factors that promote cell aggregation and adherence to teeth, leading to dental plaque formation. In this study, we have characterized the effect of CovR, a global response regulator, on glucosyltransferase expression. Inactivation of covR in strain UA159 resulted in a marked increase in the GtfB and GtfC proteins, as analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. With the use of a transcriptional reporter system of a single chromosomal copy of the PgtfB-gusA and PgtfC-gusA fusions, we confirmed the transcriptional regulation of these promoters by CovR. By in vitro electrophoretic mobility shift assays with purified CovR protein, we showed that CovR regulates these promoters directly. DNase I footprinting analyses suggest that CovR binds to large regions on these promoters near the transcription start sites. Taken together, our results indicate that CovR negatively regulates the expression of the gtfB and gtfC genes by directly binding to the promoter region. PMID:16428403

  14. Emodin affects biofilm formation and expression of virulence factors in Streptococcus suis ATCC700794.

    Science.gov (United States)

    Yang, Yan-Bei; Wang, Shuai; Wang, Chang; Huang, Quan-Yong; Bai, Jing-Wen; Chen, Jian-Qing; Chen, Xue-Ying; Li, Yan-Hua

    2015-12-01

    Streptococcus suis (S. suis) is a swine pathogen and also a zoonotic agent. In this study, the effects of subinhibitory concentrations (sub-MICs) of emodin on biofilm formation by S. suis ATCC700794 were evaluated. As quantified by crystal violet staining, biofilm formation by S. suis ATCC700794 was dose-dependently decreased after growth with 1/2 MIC, 1/4 MIC, or 1/8 MIC of emodin. By scanning electron microscopy, the structural architecture of the S. suis ATCC700794 biofilms was examined following growth in culture medium supplemented with 1/2 MIC, 1/4 MIC, 1/8 MIC, or 1/16 MIC of emodin. Scanning electron microscopy analysis revealed the potential effect of emodin on biofilm formation by S. suis ATCC700794. The expression of luxS gene and virulence genes in S. suis ATCC700794 was investigated by quantitative RT-PCR. It was found that sub-MICs of emodin significantly decreased the expression of gapdh, sly, fbps, ef, and luxS. However, it was found that sub-MICs of emodin significantly increased the expression of cps2J, mrp, and gdh. These findings showed that sub-MICs of emodin could cause the difference in the expression level of the virulence genes. PMID:26446827

  15. Diagnosis of Streptococcus pneumoniae meningitis by polymerase chain reaction amplification of the gene for pneumolysin

    Scientific Electronic Library Online (English)

    Juliana de A, Matos; Danielle J, Madureira; Maria C, Rebelo; Cristina B, Hofer; David E, Barroso.

    2006-08-01

    Full Text Available Diagnosis of bacterial meningitis has long been based on classical methods of Gram stain, serological tests, and culture of cerebrospinal fluid (CSF). The performance of these methods, especially culture and direct smear, is thwarted by failure to detect bacteria following administration of antimicr [...] obial agents and reluctance to performance lumbar punctures at admission. Indeed, patients with meningitis frequently receive antibiotics orally or by injection before the diagnosis is suspected or established. Thus an alternative method has become necessary to help clinicians and epidemiologists to management and control of bacterial meningitis. We evaluate the application of a polymerase chain reaction-based (PCR) assay for amplification of pneumolysin gene (ply) to diagnosis of Streptococcus pneumoniae meningitis. The PCR assay sensitivity for CSF was 96% (95% confidence interval, CI, 90-99%) compared to a sensitivity of 59% for culture (95% CI 49-69%), 66% for Gram stain (95% CI 56-74%), and 78% for latex agglutination test (95% CI 69-86%); PCR specificity was 100% (95% CI 83-100%). PCR results were available within 4 h of the start of the assay. This molecular approach proved to be reliable and useful to identify this bacterium compared with other classical laboratory methods for identification of bacterial meningitis pathogens.

  16. Perfil fermentativo e valor nutritivo de silagem de capim-elefante inoculada com Streptococcus bovis / Fermentation and nutritive value of elephant grass silage inoculated with Streptococcus bovis

    Scientific Electronic Library Online (English)

    D.J., Ferreira; A.M., Zanine; E.M., Santos; R.P., Lana; W.L., Silva; A.L., Souza; O.G., Pereira.

    2011-12-01

    Full Text Available O experimento foi desenvolvido objetivando-se avaliar o efeito da inoculação de estirpes de Streptococcus bovis (HC5 e JB1) sobre o pH, a produção de amônia e o valor nutricional em silagens de capim-elefante (Pennisetum purpureum Schum). O delineamento experimental foi o inteiramente casualizado, c [...] om três tratamentos: T1 - capim-elefante, T2 - capimelefante inoculado com Streptococcus bovis HC5 e T3 - capim-elefante inoculado com Streptococcus bovis JB1, utilizando cinco repetições por tratamento. A menor concentração de amônia foi observada na silagem tratada com inoculante à base Streptococcus bovis JB1 (5,90 p.100 N-total). A inoculação aumentou os teores de ácido láctico e diminuiu os teores de ácidos acético, butírico e propiônico, sendo que as silagens inoculada com Streptococcus bovis JB1 e HC5 foram os que apresentaram os maiores valores de ácido láctico. Não houve diferença estatística para os teores de MS e PB. Para os valores das fibras, a silagem de capim-elefante inoculada com Streptococcus bovis JB1 apresentou o menor valor de FDN (59,77 p.100) e HEM (26,71 p.100). O maior valor da DIVMS foi observado na silagem com Streptococcus bovis JB1, mostrando superioridade de quatro pontos percentuais (64,23 p.100) em relação ao tratamento sem inoculante bacteriano (60,35 p.100). O uso Streptococcus bovis JB1 melhora o processo fermentativo além de promover melhorarias na qualidade da fibra e na DIVMS da silagem estudada. Abstract in english The experiment was developed to evaluate the effect of strains of Streptococcus bovis (HC5 and JB1) on pH, ammonia production and nutritional value in elephant-grass silages (Pennisetum purpureum Schum). The experimental design was entirely randomized, with three treatments: T1 elephant- grass, T2 - [...] grass-elephant inoculated with Streptococcus bovis HC5, T3 - elephant grass inoculated with Streptococcus bovis JB1, totaling five replicates per treatment. The smallest value of ammonia was observed in the silage treated with inoculante the base Streptococcus bovis JB1 (5.90% N-total). Inoculation increased the levels of lactic acid and decreased levels of acetic, propionic and butyric acids, and the silages inoculated with Streptococcus bovis JB1 and HC5 were those with the highest values of lactic acid. There were not statistical differences for the tenors of dry matter (MS) and crude protein (PB). For the values of the fibers, the grass-elephant silage inoculated with Streptococcus bovis JB1, it presented the smallest value of neutral detergent fiber (59.77 %) and Hemicellulose (26.71 %). The largest value of in vitro dry matter digestibility (DIVMS) was observed in the silage with Streptococcus bovis JB1, showing superiority of four percentile points (64.23 %) in relation to the treatment without bacterial inoculante (60.35 %). The use Streptococcus bovis JB1 was efficient in the process fermentativo besides promoting would get better in the quality of the fiber and DIVMS in the studied silage.

  17. Streptococcus pneumoniae and its bacteriophages: one long argument / Streptococcus pneumoniae e seus bacteriófagos: uma prolongada controvérsia / Streptococcus pneumoniae y sus bacteriófagos: una prolongada controversia

    Scientific Electronic Library Online (English)

    Rubens, López.

    2004-09-01

    Full Text Available As enfermidades infecciosas matam anualmente cêrca de 15 milhões de pessoas. A OMS estima que 1,6 milhões dessas mortes são decorrentes de infeccões pneumocócicas. Streptococcus pneumoniae (pneumococo), uma bactéria com uma notável contribuição histórica para a biologia, é o melhor exemplo que ilust [...] ra o rápido desenvolvimento da resistência aos antibióticos, o que pode originar um grave problema sanitário. Esta revisão analisa as bases moleculares dos fatores principais de virulência no pneumococo, a cápsula e as hidrolases da parede celular e descreve novos enfoques para o desenvolvimento de ferramentas médicas inovadoras para prevenir as infecções pneumocócicas. Também foi analisado o atual conhecimento da possível contribuição dos fagos de pneumococo para a virulência desta bactéria e o uso como arma terapéutica das enzimas líticas codificadas por estes fagos. Abstract in spanish Las enfermedades infecciosas matan anualmente a unos 15 millones de personas y la OMS estima que 1,6 millones de esas muertes se deben a infecciones neumocócicas. Streptococcus pneumoniae (neumococo), una bacteria con una notable contribución histórica a la biología, es el mejor ejemplo que ilustra [...] el rápido desarrollo de la resistencia a los antibióticos, lo que puede originar un grave problema sanitario. Esta revisión analiza las bases moleculares de los dos factores principales de virulencia en el neumococo, la cápsula y las hidrolasas de la pared celular y describe nuevos enfoques para el desarrollo de nuevas herramientas médicas para prevenir las infecciones neumocócicas. También se analizan el conocimiento actual de la posible contribución de los fagos de neumococo a la virulencia de esta bacteria y el uso como arma terapéutica de las enzimas líticas codificadas por estos fagos. Abstract in english Infectious diseases currently kill more than 15 million people annually, and the WHO estimates that every year 1.6 million people die from pneumococcal diseases. Streptococcus pneumoniae (pneumococcus), a bacterium with along biological pedigree, best illustrates the rapid evolution of antibiotic re [...] sistance,which has led to major public health concern. This article discusses the molecularbasis of the two main virulence factors of pneumococcus, the capsule and cell-wall hydrolases, as well as new approaches to developing medicinal weapons for preventing pneumococcal infections. In addition, current knowledge regarding pneumococcal phages as potential contributors to virulence and the use of lytic enzymes encoded by these phages as therapeutic tools is reviewed.

  18. Radioprotective Agents

    Directory of Open Access Journals (Sweden)

    Ilker Kelle

    2008-01-01

    Full Text Available Since1949, a great deal of research has been carried out on the radioprotective activity of various chemical substances. Thiol compounds, compounds which contain –SH radical, different classes of pharmacological agents and other compounds such as vitamine C and WR-2721 have been shown to reduce mortality when administered prior to exposure to a lethal dose of radiation. Recently, honey bee venom as well as that of its components melittin and histamine have shown to be valuable in reduction of radiation-induced damage and also provide prophylactic alternative treatment for serious side effects related with radiotherapy. It has been suggested that the radioprotective activity of bee venom components is related with the stimulation of the hematopoetic system.

  19. Analysis of the in vitro adherence of Streptococcus mutans and Candida albicans Análise da aderência in vitro de Streptococcus mutans e Candida albicans

    OpenAIRE

    Dicler de Sant'Anna Vitor Barbieri; Vânia Aparecida Vicente; Fabian Calixto Fraiz; Osmir José Lavoranti; Terezinha Inês Estivalet Svidzinski; Rosângela Lameira Pinheiro

    2007-01-01

    The objective of the present study was to investigate the in vitro adherence capacity of Streptococcus mutans and Candida albicans. Adherence assays were conducted on dental surfaces and analyzed by scanning electron microscopy (SEM). Extracted human teeth were inoculated with Streptococcus mutans or Candida albicans and with both species simultaneously, and incubated at 37ºC for 21 days. Bacterial inocula had been obtained from saliva samples of children that had been colonized by both organ...

  20. Tn5253 Family Integrative and Conjugative Elements Carrying mef(I) and catQ Determinants in Streptococcus pneumoniae and Streptococcus pyogenes

    OpenAIRE

    Mingoia, Marina; Morici, Eleonora; Morroni, Gianluca; Giovanetti, Eleonora; Del Grosso, Maria; Pantosti, Annalisa; Varaldo, Pietro E.

    2014-01-01

    The linkage between the macrolide efflux gene mef(I) and the chloramphenicol inactivation gene catQ was first described in Streptococcus pneumoniae (strain Spn529), where the two genes are located in a module designated IQ element. Subsequently, two different defective IQ elements were detected in Streptococcus pyogenes (strains Spy029 and Spy005). The genetic elements carrying the three IQ elements were characterized, and all were found to be Tn5253 family integrative and conjugative element...

  1. Clonal characterization of Streptococcus mutans strains by multilocus enzyme electrophoresis Caracterização clonal de cepas de Streptococcus mutans por eletroforese de enzimas codificadas por multilocus

    OpenAIRE

    Rosimeire Takaki Rosa; Marcelo Henrique Napimoga; José Francisco Höfling; Reginaldo Bruno Gonçalves; Edvaldo Antonio Ribeiro Rosa

    2006-01-01

    Twenty-one Streptococcus mutans strains were clustered by Multilocus Enzyme Electrophoresis (MLEE). Six isoenzymes showed strong infra-specific discriminatory power (M1P, MPI, PLP, NSP, GOT, and LAP). MLEE is a robust technique that may be used to explore clonal diversity of S. mutans isolates in epidemiological surveys.Vinte e uma cepas de Streptococcus mutans foram agrupadas pela eletroforese de enzimas codificadas por multilocus (MLEE). Seis isoenzimas apresentaram forte poder discriminató...

  2. Meningite neonatal por Streptococcus pyogenes e trombose de seio sagital: relato de caso Neonatal Streptococcus pyogenes meningitis and sagittal sinus thrombosis: case report

    OpenAIRE

    VERA LÚCIA JORNADA KREBS; LUCIANA NAVARRETTI CHIEFFI; MARIA ESTHER JURFEST RIVERO CECCON; EDNA MARIA DE ALBUQUERQUE DINIZ; RUBENS FEFERBAUM; CARLOS AUGUSTO TAKEUCHI; MARIA JOAQUINA MARQUES-DIAS; JORGE DAVID AIVAZOGLOU CARNEIRO; FLÁVIO ADOLFO COSTA VAZ

    1998-01-01

    Relatamos um caso de meningite por Streptococcus pyogenes em menina de 18 dias de vida, com evolução complicada por trombose de seio sagital. São discutidos alguns aspectos da patogênese, tratamento e seguimento da doença. Frente ao aumento mundial das infecções estreptocócicas graves nos últimos 10 anos, é provável que a meningite neonatal por Streptococcus pyogenes se torne mais frequente no futuro, sendo importante estar alerta para o diagnóstico precoce e as possíveis complicações dessa i...

  3. Human Streptococcus agalactiae strains in aquatic mammals and fish

    Directory of Open Access Journals (Sweden)

    Delannoy Christian MJ

    2013-02-01

    Full Text Available Abstract Background In humans, Streptococcus agalactiae or group B streptococcus (GBS is a frequent coloniser of the rectovaginal tract, a major cause of neonatal infectious disease and an emerging cause of disease in non-pregnant adults. In addition, Streptococcus agalactiae causes invasive disease in fish, compromising food security and posing a zoonotic hazard. We studied the molecular epidemiology of S. agalactiae in fish and other aquatic species to assess potential for pathogen transmission between aquatic species and humans. Methods Isolates from fish (n = 26, seals (n = 6, a dolphin and a frog were characterized by pulsed-field gel electrophoresis, multilocus sequence typing and standardized 3-set genotyping, i.e. molecular serotyping and profiling of surface protein genes and mobile genetic elements. Results Four subpopulations of S. agalactiae were identified among aquatic isolates. Sequence type (ST 283 serotype III-4 and its novel single locus variant ST491 were detected in fish from Southeast Asia and shared a 3-set genotype identical to that of an emerging ST283 clone associated with invasive disease of adult humans in Asia. The human pathogenic strain ST7 serotype Ia was also detected in fish from Asia. ST23 serotype Ia, a subpopulation that is normally associated with human carriage, was found in all grey seals, suggesting that human effluent may contribute to microbial pollution of surface water and exposure of sea mammals to human pathogens. The final subpopulation consisted of non-haemolytic ST260 and ST261 serotype Ib isolates, which belong to a fish-associated clonal complex that has never been reported from humans. Conclusions The apparent association of the four subpopulations of S. agalactiae with specific groups of host species suggests that some strains of aquatic S. agalactiae may present a zoonotic or anthroponotic hazard. Furthermore, it provides a rational framework for exploration of pathogenesis and host-associated genome content of S. agalactiae strains.

  4. Genomics of Streptococcus salivarius, a major human commensal.

    Science.gov (United States)

    Delorme, Christine; Abraham, Anne-Laure; Renault, Pierre; Guédon, Eric

    2015-07-01

    The salivarius group of streptococci is of particular importance for humans. This group consists of three genetically similar species, Streptococcus salivarius, Streptococcus vestibularis and Streptococcus thermophilus. S. salivarius and S. vestibularis are commensal organisms that may occasionally cause opportunistic infections in humans, whereas S. thermophilus is a food bacterium widely used in dairy production. We developed Multilocus sequence typing (MLST) and comparative genomic analysis to confirm the clear separation of these three species. These analyses also identified a subgroup of four strains, with a core genome diverging by about 10%, in terms of its nucleotide sequence, from that of S. salivarius sensu stricto. S. thermophilus species displays a low level of nucleotide variability, due to its recent emergence with the development of agriculture. By contrast, nucleotide variability is high in the other two species of the salivarius group, reflecting their long-standing association with humans. The species of the salivarius group have genome sizes ranging from the smallest (? 1.7 Mb for S. thermophilus) to the largest (? 2.3 Mb for S. salivarius) among streptococci, reflecting genome reduction linked to a narrow, nutritionally rich environment for S. thermophilus, and natural, more competitive niches for the other two species. Analyses of genomic content have indicated that the core genes of S. salivarius account for about two thirds of the genome, indicating considerable variability of gene content and differences in potential adaptive features. Furthermore, we showed that the genome of this species is exceptionally rich in genes encoding surface factors, glycosyltransferases and response regulators. Evidence of widespread genetic exchanges was obtained, probably involving a natural competence system and the presence of diverse mobile elements. However, although the S. salivarius strains studied were isolated from several human body-related sites (all levels of the digestive tract, skin, breast milk, and body fluids) and included clinical strains, no genetic or genomic niche-specific features could be identified to discriminate specific group. PMID:25311532

  5. Agglutination of Streptococcus suis by sialic acid-binding lectins.

    OpenAIRE

    Charland, N; Kellens, J T; Caya, F; M. Gottschalk

    1995-01-01

    The 35 Streptococcus suis capsular-type reference strains as well as 45 field strains of type 2 were tested with sialic acid-binding lectins from Sambucus nigra (SNA I), Triticum vulgaris, Maackia amurensis, Homarus americanus, and Limax flavus. Only types 1, 1/2, 2, 14, 15, and 16 agglutinated with SNA I and/or the T. vulgaris lectin. All field strains agglutinated only with SNA I. Reaction with SNA I was probably due to the sialic acid moiety since it disappeared after sialidase treatment. ...

  6. Studies on the immunogenicity of Streptococcus equi vaccines in foals.

    OpenAIRE

    Srivastava, S. K.; Barnum, D.A.

    1985-01-01

    The ability of either formalin-treated or heat-inactivated whole Streptococcus equi cell vaccines or partially purified M-protein of S. equi to give rise to protective antibody levels was studied in Standardbred foals by serological means. Two commercial preparations, i.e. a beta-propiolactone killed whole S. equi cell bacterin and a cell-free extract of S. equi cells were included in the study. The mean passive hemagglutination antibody titers (10 X log2) in sera of foals given either four d...

  7. Sucrose metabolism contributes to in vivo fitness of Streptococcus pneumoniae

    OpenAIRE

    Iyer, Ramkumar; Camilli, Andrew

    2007-01-01

    We characterized two sucrose-metabolizing systems – sus and scr – and describe their roles in the physiology and virulence of Streptococcus pneumoniae in murine models of carriage and pneumonia. The sus and scr systems are regulated by LacI family repressors SusR and ScrR respectively. SusR regulates an adjacent ABC transporter (susT1/susT2/susX) and sucrose-6-phosphate (S-6-P) hydrolase (susH). ScrR controls an adjacent PTS transporter (scrT), fructokinase (scrK) and second S-6-P hydrolase (...

  8. Pneumococcal Surface Protein A Inhibits Complement Activation by Streptococcus pneumoniae

    OpenAIRE

    Tu, Anh-Hue T.; Fulgham, Robert L.; McCrory, Mark A.; Briles, David E.; Szalai, Alexander J

    1999-01-01

    Pneumococcal surface protein A (PspA) is a surface-exposed protein virulence factor for Streptococcus pneumoniae. In this study, no significant depletion of serum complement was observed for the serum of mice infected with pneumococci that express PspA. In contrast, in mice infected with an isogenic strain of pneumococci lacking PspA, significant activation of serum complement was detected within 30 min after infection. Also, the PspA-deficient strain but not the PspA-expressing strain was cl...

  9. Vitamin B6 requirements of nutritionally variant Streptococcus mitior.

    OpenAIRE

    Schiller, N. L.; Roberts, R. B.

    1982-01-01

    The growth rate of three vitamin B6-dependent Streptococcus mitior (B6DS) and two non-B6DS strains in Todd-Hewitt broth, with and without vitamin B6 supplementation, was examined. Even in optimally supplemented culture media, the growth rate of the three B6DS strains was much slower than that of comparable non-B6DS strains. Uptake studies with [3H] pyridoxine suggest that these B6DS strains cannot assimilate pyridoxine. Although not transported intracellularly, pyridoxine inhibited the growth...

  10. Isolation, Production And Purification Of Streptokinase From Streptococcus Pyogenes

    Directory of Open Access Journals (Sweden)

    V.S. Shembekar

    2013-07-01

    Full Text Available Streptokinase a fibrinolytic enzyme is very effective in treating acute myocardial infarction and it iscertainly more cost-effective. In view of the relatively recent availability of the competing recombinant tPA,skepticism is being expressed about the continued viability of streptokinase therapy. Despite this research onstreptokinase continues, and it remains a vital and affordable therapy especially in the world's poorer healthcaresystems. Our present study focuses on the production of streptokinase from Streptococcus pyogenes species andpartial purification of streptokinase by ammonium sulfate precipitation, dialysis and column chromatography. Theenzyme is quantified by Lowry's method and its electrophoretic mobility and molecular weight were determined bySDS-PAGE.

  11. Toxicity Study of Streptococcus pneumoniae Vaccine Administrated Subcutaneously in Rats

    OpenAIRE

    Park, Sin Jeong; Seo, Kook Heon; Han, Sang In

    2011-01-01

    This study was performed to evaluate the toxicity of polysaccharide-based Streptococcus pneumoniae vaccine in Specific Pathogen Free (SPF), Sprague-Dawley (SD) rats. S. pneumoniae vaccine was administrated subcutaneously each dose level of high (560 ?g/rat), medium (280 ?g/rat) and low (140 ?g/rat) on days 0, 14, 28. The rats were observed for 2 weeks or 4 weeks after the final injection. During this test, there were no significant dose-dependent changes in body weight, water and food consump...

  12. Deletion of a Cation Transporter Promotes Lysis in Streptococcus pneumoniae ? †

    OpenAIRE

    Neef, Jolanda; Andisi, Vahid Farshchi; Kim, Kwang S; Kuipers, Oscar P.; Bijlsma, Jetta J. E.

    2011-01-01

    Streptococcus pneumoniae is a significant human pathogen which causes respiratory and serious invasive diseases. Mg2+ is essential for life, and its concentration varies throughout the human body. Magnesium uptake plays an important role in the virulence of many bacterial pathogens. To study the Mg2+ uptake of S. pneumoniae strain D39, a mutant was generated in SPD1383, a P-type ATPase with homology to the Salmonella Mg2+ transporter MgtA, which has also been shown to be a Ca2+ exporter in st...

  13. Identification of a purC gene from Streptococcus pneumoniae.

    OpenAIRE

    Hui, F M; Morrison, D. A.

    1993-01-01

    A gene encoding 5'-phosphoribosyl-5-aminoimidazole-4-N-succinocarboxamide synthetase was identified in Streptococcus pneumoniae as a 708-bp segment of the genome encoding a 27,001-Da protein with strong similarity to known PurC proteins. The S. pneumoniae purC gene, found immediately adjacent to the competence induction genes, comAB, was cloned and sequenced. The predicted protein product of purC displayed substantial (> 40%) identity to the entire sequence of the PurC proteins of Bacillus su...

  14. Binding of Todd-Hewitt broth antigens by Streptococcus mutans.

    OpenAIRE

    Stinson, M. W.; Jones, C. A.

    1983-01-01

    Streptococcus mutans 10449, grown in chemically defined culture medium, was tested for its ability to bind 3H-labeled Todd-Hewitt broth components (greater than 12,000 Mr). Maximum adsorption of radioactivity occurred within 5 min at room temperature, and cell-bound material was not completely removed by extended washing with buffer. Heat-killed, arsenate-inhibited, and viable bacteria bound similar quantities. Only 0.09% of the radioactivity in the preparation of high Mr Todd-Hewitt broth co...

  15. The cell envelope subtilisin-like proteinase is a virulence determinant for Streptococcus suis

    Directory of Open Access Journals (Sweden)

    Gottschalk Marcelo

    2010-02-01

    Full Text Available Abstract Background Streptococcus suis is a major swine pathogen and zoonotic agent that mainly causes septicemia, meningitis, and endocarditis. It has recently been suggested that proteinases produced by S. suis (serotype 2 are potential virulence determinants. In the present study, we screened a S. suis mutant library created by the insertion of Tn917 transposon in order to isolate a mutant deficient in a cell surface proteinase. We characterized the gene and assessed the proteinase for its potential as a virulence factor. Results Two mutants (G6G and M3G possessing a single Tn917 insertion were isolated. The affected gene coded for a protein (SSU0757 that shared a high degree of identity with Streptococccus thermophilus PrtS (95.9% and, to a lesser extent, with Streptococcus agalactiae CspA (49.5%, which are cell surface serine proteinases. The SSU0757 protein had a calculated molecular mass of 169.6 kDa and contained the catalytic triad characteristic of subtilisin family proteinases: motif I (Asp200, motif II (His239, and motif III (Ser568. SSU0757 also had the Gram-positive cell wall anchoring motif (Leu-Pro-X-Thr-Gly at the carboxy-terminus, which was followed by a hydrophobic domain. All the S. suis isolates tested, which belonged to different serotypes, possessed the gene encoding the SSU0757 protein. The two mutants devoid of subtilisin-like proteinase activity had longer generation times and were more susceptible to killing by whole blood than the wild-type parent strain P1/7. The virulence of the G6G and M3G mutants was compared to the wild-type strain in the CD1 mouse model. Significant differences in mortality rates were noted between the P1/7 group and the M3G and G6G groups (p Conclusion In summary, we identified a gene coding for a cell surface subtilisin-like serine proteinase that is widely distributed in S. suis. Evidences were brought for the involvement of this proteinase in S. suis virulence.

  16. Cellular response of the bovine mammary gland after Weissella confusa infusion to control Streptococcus agalactiae / Respuesta celular de la glándula mamaria bovina después de la infusión con Weissella confusa para el control de Streptococcus agalactiae

    Scientific Electronic Library Online (English)

    Liliana, Serna-Cock; Cruz E, Enríquez; Rómulo, Campos Gaona; Andrea, Vásquez.

    2013-12-01

    Full Text Available Antecedentes: previamente foi proposto o uso de bactérias ácido-lácticas (LAB), como agentes terapêuticos potenciais para o controle da mastite bovina. No entanto, pouca pesquisa tem sido feita sobre a resposta celular da glândula mamária de bovinos após aplicação de LAB em bovinos infectados com St [...] reptococcus agalactiae. Objetivo: avaliar, em vacas em período de lactação, a resposta celular da glândula mamária após a infecção com Streptococcus agalactiae e a infusão dentro da teta de Weissella confusa como tratamento. Métodos: tetas saudáveis de gado nativo Harton del Valle em lactação foram infectados com S. agalactiae (10(7)ufc/mL). Ventiquatro horas após a infusão do agente patogénico, a 50% dos quartos foi administrada W. confusa em concentração de 10(9) ufc/mL (quartos SW) e 50% dos quartos foram usados como unidades experimentais de controle (quartos S). Nos dias 1, 2, 3, 4, 5, 11 e 14 após a infusão do agente patogénico, foram avaliados os sinais clínicos de mastite e o grau de resposta celular da glândula mamária através do Califórnia Mastite Teste, contagem de células somáticas, condutividade elétrica e diferencial de leucócitos do leite. Resultados: nos quartos SW observou-se evidência clínica de inflamação da glândula mamária associado ao aumento significativo na contagem de células somáticas, Califórnia mastite teste, condutividade eléctrica, e altas porcentagens de neutrófilos polimorfonucleares. Os resultados sugerem que a infusão de células de W. confusa gera maior resposta celular na glândula mamária bovina que o S. agalactiae. Conclusões: os resultados indicam que a infusão de células vivas de W. confusa como um tratamento para o controle de S. agalactiae não pode ser usado. Outros métodos de uso da LAB para o tratamento de mastite devem ser pesquisados. Abstract in spanish Antecedentes: previamente se propuso el uso de bacterias ácido lácticas (LAB) como agentes terapéuticos potenciales para el control de mastitis bovina. Sin embargo, poco se ha investigado sobre la respuesta celular de la glándula mamaria bovina ante la aplicación de LAB en bovinos infectados con Str [...] eptococcus agalactiae. Objetivo: evaluar, en vacas lactantes, la respuesta celular de la glándula mamaria después de la infección con Streptococcus agalactiae y la infusión intrapezón con Weissella confusa como tratamiento. Métodos: cuartos sanos de ganado criollo Hartón del Valle en estado de lactancia, se infectaron con S. agalactiae (10(7)ufc/ mL). Transcurridas 24 horas post-infusión del patógeno, al 50% de los cuartos se les aplicó W. confusa a concentración de 10(9) ufc/mL (cuartos SW) y el 50% de los cuartos restantes se tomaron como unidades experimentales control (cuartos S). En los días 1, 2, 3, 4, 5, 11 y 14 pos-infusión del patógeno, se evaluaron signos clínicos de mastitis y el grado de respuesta celular de la glándula mamaria, a través de california mastitis test, recuento de células somáticas, conductividad eléctrica y diferencial de leucocitos en leche. Resultados: en los cuartos SW se observaron evidencias clínicas de inflamación de la glándula mamaria asociada con incremento significativo de recuento de células somáticas, California mastitis test, conductividad eléctrica, y altos porcentajes de neutrófilos polimorfonucleares. Los resultados sugieren que la infusión con células de W. confusa genera mayor respuesta celular en la glándula mamaria bovina que S. agalactiae. Conclusiones: los resultados indican que no puede utilizarse la infusión de células vivas de W. confusa como tratamiento para el control de S. agalactiae. Se debe investigar otro mecanismo de uso de la LAB para el tratamiento de mastitis bovina. Abstract in english Background: the use of lactic acid bacteria (LAB) as a potential therapeutic agent to control bovine mastitis was previously proposed. However, little is known about the cellular response of the bovine mammary gland in cattle infected with Streptococcus agalactiae and

  17. Aspectos clinicos y neuroinmunologicos de la meningoencefalitis por Streptococcus pneumoniae / Clinical and neuroimmunological aspects of meningoencephalitis by Streptococcus pneumoniae

    Scientific Electronic Library Online (English)

    Raisa, Bu-Coifiu; Alberto J., Dorta; Elena, Noris; Bárbara, Padilla; Marlén, González.

    2007-12-01

    Full Text Available Después de exitosas campañas de vacunación contra Neisseria meningitidis y Haemophilus influenzae hubo un aumento de casos de meningoencefalitis por Streptococcus pneumoniae. Con el objetivo de describir las características clínicas, los hallazgos de laboratorio y las complicaciones encontradas a un [...] grupo de pacientes que sufrieron de esta enfermedad entre 1993 y 2006, evaluar el estado de la barrera sangre-líquido cefalorraquídeo (LCR) y el patrón de respuesta de síntesis intratecal de inmunoglobulinas a través del reibergrama, se estudiaron 12 niños con meningoencefalitis por Streptococcus pneumoniae que ingresaron en el Hospital Pediátrico de San Miguel del Padrón, Ciudad de La Habana, en ese periodo. Se dosificaron albúmina, IgA, IgM e IgG y sus subclases por inmunodifusión radial en suero y líquido cefalorraquídeo. La edad más frecuente resultó la menor de un año. Las mayores complicaciones fueron: shock séptico y edema cerebral. Hubo tres pacientes fallecidos. Los patrones de las tres clases mayores de inmunoglobulinas aparecieron en el 33% del total. Los dos patrones de subclases de IgG más IgM tuvieron en común la disfunción de la barrera sangre-líquido cefalorraquídeo. La respuesta inmune intratecal en los pacientes con meningoencefalitis por Streptococcus pneumoniae tiene características distintivas que lo diferencian de otras meningoencefalitis de origen bacteriano por lo que en su conjunto podrían ser elementos a ser tomados en cuenta para auxiliar al médico en su diagnóstico diferencial y en la táctica para una vacuna cubana Abstract in english After successful vaccination campaigns against Neisseria meningitidis and Haemophilus influenzae, there was an increase of cases of meningoencephalitis by Streptococcus pneumoniae. With the aim to describe the clinical characteristics, laboratory findings and complications found in a group of patien [...] ts suffering from this disease between 1993 and 2006, to evaluate the state of the barrier blood-cephalo rachideous liquid (LCR) and the response pattern of intratecal synthesis of immunogobulins through reibergram, 12 children with meningo-encephalitis by Streptococcus pneumoniae who were hospitalized in the Pediatric Hospital of San Miguel del Padrón, Havana City, were studied. Albumin, IgA, IgM and IgG and their subclasses were dossified by radial immuno-diffusion in serum and cephalo-rachideous liquid. The most frequent age was that lower than one year. The greater complications were: septic and brain edema. There were three deceased patients. Patterns of the three greater classes of immunoglobulins appeared in 33% from the total. The two patterns of subclasses of IgG more IgM had in common the dysfunction of the barrier blood-cephalorachideous liquid. The intratecal immune response in patients with meningo-encephalitis by Streptococcus pneumoniae has distinctive characteristics differentiating it from other meningoencephalitis of bacterial origin; so as a whole they could be elements to be taken into account to help the doctor in its differential diagnosing and in the tactic to develop a Cuban vaccine.

  18. General Game Management Agent

    OpenAIRE

    Tagiew, Rustam

    2009-01-01

    The task of managing general game playing in a multi-agent system is the problem addressed in this paper. It is considered to be done by an agent. There are many reasons for constructing such an agent, called general game management agent. This agent manages strategic interactions between other agents - players, natural or also artificial. The agent records the interaction for further benchmarking and analysis. He can also be used for a kind of restricted communications. His...

  19. MOBILE AGENT: EMERGING TECHNOLOGY

    OpenAIRE

    RAJGURU P. V. DR. DESHMUKH S. D

    2011-01-01

    Mobile agent technology has been promoted as an emerging technology that makes it much easier to design, implement, and maintain distributed systems, introduction to basic concepts of mobile agents like agent mobility, agent types and places and agent communication. Then benefits of the usage of mobile agents are summarized and illustrated by selected applications. The next section lists requirements and desirable properties for mobile agent languages and systems. We study the main features, ...

  20. Languages for Mobile Agents

    OpenAIRE

    Versteeg, Steve

    2015-01-01

    Mobile agents represent a new model for network computing. Many different languages have been used to implement mobile agents. The characteristics that make a language useful for writing mobile agents are: (1) their support of agent migration, (2) their support for agent-to-agent communication, (3) how they allow agents to interact with local resources, (4) security mechanisms, (5) execution efficiency, (6) language implementation across multiple platforms, and (7) the langu...

  1. IMMUNOSUPPRESSIVE AGENTS

    Directory of Open Access Journals (Sweden)

    Dr Pramila Yadav

    2010-05-01

    Full Text Available Immunosuppressive drugs play an important role in preventing the rejection of organ or tissue grafts and in the treatment of certain diseases that arise from dysregulation of the immune response. In recent years, many new immunosuppressive drugs have been discovered and developed for clinical use. The wide array of new drugs offers the opportunity to use combinations that block different pathways of immune activation. In transplantation, the major classes of immunosuppressive drugs used are: Glucocorticoids, calcineurin inhibitors, antiproliferative/antimetabolic agents, and biologics (antibodies. Newer drugs like Mizoribine, RS61443, Brequinar sodium are inhibitors of DNA synthesis and inhibitors of cell activation/maturation like (Deoxyspergualin, CP 17193 have also showed promising results. Tacrolimus (FK 506 and Mycophenolate mofetil (MMF have already replaced immunosuppressive maintenance protocols. The other two drugs, Leflunomide and Sirolimus (SRL, are still under investigation for use in solid organ transplantation. Anti-interleukin-2 (IL-2 receptor antibodies, anti-CD25 [interleukin (IL-2 receptor] antibodies (basiliximab, daclizumab target growth factor pathways, have shown promising results in phase III trials. These drugs have met with a high degree of clinical success in treating conditions such as acute immune rejection of organ transplants and severe autoimmune diseases. This article reviews the pharmacodynamics, adverse effects and uses of the major classes of immunosuppressive drugs.

  2. Production of monoclonal antibodies against Streptococcus mutans antigens / Produção de anticorpos monoclonais contra antígenos de Streptococcus mutans

    Scientific Electronic Library Online (English)

    Antonio Carlos Victor, Canettieri; Fujiko Yamasiro, Kretchetoff; Cristiane Yumi, Koga-Ito; Daniella, Moreira; Fabio José Condino, Fujarra; Carmelinda Schmidt, Unterkircher.

    2006-12-01

    Full Text Available Diversos estudos foram realizados nas últimas décadas com o intuito de se obter uma vacina anticárie dentária, mas alguns trabalhos têm demonstrado reatividade cruzada entre antígenos de superfície de Streptococcus mutans e tecido cardíaco humano. Neste trabalho, foi testada a reatividade de cinco a [...] nticorpos monoclonais (AcMo) anti-Streptococcus mutans (24A, 56G, C8, E8 e F6) contra estreptococos orais, antígenos cardíacos e miosinas esquelética e cardíaca, no intuito de avaliar a especificidade desses AcMo. Os híbridos produtores de imunoglobulinas da classe IgG2b foram clonados por diluição limite e expandidos in vivo. Os AcMo foram testados por ELISA. O híbrido 24A reagiu com S. mutans CCT 1910, S. salivarius CCT 0365 e S. pyogenes T23. Nenhuma diferença de reatividade foi detectada entre as espécies analisadas. Reatividade cruzada com coração e miosina cardíaca não foi confirmada, existindo somente reação com miosina de músculo esquelético (p = 0,0381). O híbrido 56G reagiu com todos os microrganismos testados e houve diferença estatisticamente significante entre S. mutans e S. pyogenes T23 (p Abstract in english Several studies have been conducted in the last decades aiming to obtain an anti-caries vaccine, however some studies have demonstrated cross reactivity between Streptococcus mutans surface antigens and the human cardiac tissue. In this work, the reactivity of five anti-Streptococcus mutans monoclon [...] al antibodies (MoAb) (24A, 56G, C8, E8 and F6) was tested against oral streptococci, cardiac antigens and skeletal and cardiac myosins, aiming to evaluate the specificity of these MoAb. The hybrid producers of immunoglobulins of the IgG2b class were cloned by limit dilution and expanded in vivo. MoAb were tested by ELISA. The hybrid 24A reacted with S. mutans CCT 1910, S. salivarius CCT 0365 and S. pyogenes T23. No reactivity difference was observed among the tested species. Cross reactivity with heart and cardiac myosin was not confirmed and only reaction with myosin of skeletal muscle was observed (p = 0.0381). The hybrid 56G reacted with all the tested microorganisms and there was statistically significant difference between S. mutans and S. pyogenes T23 (p

  3. Experimental model of type IV Streptococcus agalactiae (group B streptococcus) infection in mice with early development of septic arthritis.

    OpenAIRE

    Tissi, L; Marconi, P.; Mosci, P; Merletti, L; Cornacchione, P; Rosati, E; Recchia, S; von Hunolstein, C; Orefici, G

    1990-01-01

    We have established an experimental murine model to gain insight into the pathogenicity and clinical features of type IV group B streptococcus (GBS) infections. Adult CD-1 mice were challenged intravenously with 10(7) type IV GBS cells, inducing systemic invasion. Most of the animals were able to clear the infection from the blood, brain, and lungs within 2 weeks and from the spleen and liver within 1 month. However, the animals were unable to clear the microorganism from the joints and kidne...

  4. Detection of Streptococcus pyogenes using rapid visual molecular assay.

    Science.gov (United States)

    Zhao, Xiangna; He, Xiaoming; Li, Huan; Zhao, Jiangtao; Huang, Simo; Liu, Wei; Wei, Xiao; Ding, Yiwei; Wang, Zhaoyan; Zou, Dayang; Wang, Xuesong; Dong, Derong; Yang, Zhan; Yan, Xiabei; Huang, Liuyu; Du, Shuangkui; Yuan, Jing

    2015-09-01

    Streptococcus pyogenes is an increasingly important pathogen in many parts of the world. Rapid and accurate detection of S. pyogenes aids in the control of the infection. In this study, a loop-mediated isothermal amplification (LAMP) assay was developed and validated for the specific detection of S. pyogenes. The assay incorporates two methods: a chromogenic analysis using a calcein/Mn(2+) complex and real-time turbidity monitoring to assess the reaction. Both methods detected the target DNA within 60 min under 64°C isothermal conditions. The assay used specifically designed primers to target spy1258, and correctly identified 111 strains of S. pyogenes and 32 non-S. pyogenes strains, including other species of the genus Streptococcus. Tests using reference strains showed that the LAMP assay was highly specific. The sensitivity of the assay, with a detection limit of 1.49 pg DNA, was 10-fold greater than that of PCR. The LAMP assay established in this study is simple, fast and sensitive, and does not rely upon any special equipment; thus, it could be employed in clinical diagnosis. PMID:26319025

  5. Screening for group B streptococcus: a private laboratory experience.

    Science.gov (United States)

    Cristea, Violeta-Corina; Du??, Maria; Neac?u, Gabriela

    2011-01-01

    We examined group B streptococcus (GBS) isolates colonizing women at the 35-37 weeks of pregnancy. A total of 257 group B streptococcus (GBS) isolates for serotyped using direct agglutination with a set of commercially available antisera (Ia, Ib, II, III, IV, and V) and tested for susceptibility to antimicrobials (penicillin, macrolides, lincosamides, fluoroquinolones and tetracyclines). Fourteen isolates could not be serotyped with the antisera set used in the study. Serotype III was the predominant serotype (33%), followed by serotypes V (23%), and Ia (20%). Whereas all isolates were susceptible to penicillin, the rates of susceptibility to the other antimicrobials tested were the following: 91% for ofloxacin, 80% for clindamycin, 77% for erythromycin, and 4% for tetracycline. More than half (67%) of the macrolide resistant isolates belonged to serotypes V and III. A systematic surveillance of the autochthonous GBS serotypes, performed at the level of laboratories processing a high number of human specimens, is mandatory for strengthening the national epidemiological GBS surveillance. While penicillin remains the drug of choice for intrapartum prophylaxis, the resistance of autochthonous GBS isolates to other antibiotics should be actively monitored. PMID:22106511

  6. Comparative molecular analysis of ovine and bovine Streptococcus uberis isolates.

    Science.gov (United States)

    Gilchrist, T L; Smith, D G E; Fitzpatrick, J L; Zadoks, R N; Fontaine, M C

    2013-02-01

    Streptococcus uberis causes clinical and subclinical mastitis in cattle and sheep, but it is unknown whether the composition of Strep. uberis populations differs between host species. To address this, we characterized a collection of bovine and ovine Strep. uberis isolates with shared geographical and temporal origins by means of an expanded multilocus sequence typing scheme. Among 14 ovine and 35 bovine isolates, 35 allelic profiles were detected. Each allelic profile was associated with a single host species and all but one were new to the multilocus sequence typing database. The median number of new alleles per isolate was higher for ovine isolates than for bovine isolates. None of the ovine isolates belonged to the global clonal complexes 5 or 143, which are commonly associated with bovine mastitis and which have a wide geographical distribution. Ovine isolates also differed from bovine isolates in carriage of plasminogen activator genes, with significantly higher prevalence of pauB in ovine isolates. Isolates that were negative for yqiL, one of the targets of multilocus sequence typing, were found among ovine and bovine isolates and were not associated with a specific sequence type or global clonal complex. One bovine isolate carried a gapC allele that was probably acquired through lateral gene transfer, most likely from Streptococcus salivarius. We conclude that ovine isolates are distinct from bovine isolates of Strep. uberis, and that recombination between isolates from different host species or bacterial species could contribute to changes in virulence gene profiles with relevance for vaccine development. PMID:23200465

  7. Lysogenic Transfer of Group A Streptococcus Superantigen Gene among Streptococci

    Science.gov (United States)

    Vojtek, Ivo; Pirzada, Zaid A.; Henriques-Normark, Birgitta; Mastny, Markus; Janapatla, Rajendra P.; Charpentier, Emmanuelle

    2010-01-01

    A group A Streptococcus(GAS) isolate,serotypeM12,recovered from a patient with streptococcal toxic shock syndrome was analyzed for superantigen-carrying prophages, revealing 149, which encodes superantigen SSA. Sequence analysis of the att-L proximal region of 149 showed that the phage had a mosaic nature. Remarkably, we successfully obtained lysogenic conversion of GAS clinical isolates of various M serotypes (M1, M3, M5, M12, M19, M28, and M94), as well as of group C Streptococcus equisimilis (GCSE) clinical isolates, via transfer of a recombinant phage 149::Kmr. Phage149::Kmr from selected lysogenized GAS and GCSE strains could be transferred back to M12 GAS strains. Our data indicate that horizontal transfer of lysogenic phages among GAS can occur across the M-type barrier; these data also provide further support for the hypothesis that toxigenic conversion can occur via lysogeny between species. Streptococci might employ this mechanism specifically to allow more efficient adaptation to changing host challenges, potentially leading to fitter and more virulent clones. PMID:18179387

  8. Mechanisms of group A Streptococcus resistance to reactive oxygen species.

    Science.gov (United States)

    Henningham, Anna; Döhrmann, Simon; Nizet, Victor; Cole, Jason N

    2015-07-01

    Streptococcus pyogenes, also known as group A Streptococcus (GAS), is an exclusively human Gram-positive bacterial pathogen ranked among the 'top 10' causes of infection-related deaths worldwide. GAS commonly causes benign and self-limiting epithelial infections (pharyngitis and impetigo), and less frequent severe invasive diseases (bacteremia, toxic shock syndrome and necrotizing fasciitis). Annually, GAS causes 700 million infections, including 1.8 million invasive infections with a mortality rate of 25%. In order to establish an infection, GAS must counteract the oxidative stress conditions generated by the release of reactive oxygen species (ROS) at the infection site by host immune cells such as neutrophils and monocytes. ROS are the highly reactive and toxic byproducts of oxygen metabolism, including hydrogen peroxide (H2O2), superoxide anion (O2•(-)), hydroxyl radicals (OH•) and singlet oxygen (O2*), which can damage bacterial nucleic acids, proteins and cell membranes. This review summarizes the enzymatic and regulatory mechanisms utilized by GAS to thwart ROS and survive under conditions of oxidative stress. PMID:25670736

  9. A molecular trigger for intercontinental epidemics of group A Streptococcus.

    Science.gov (United States)

    Zhu, Luchang; Olsen, Randall J; Nasser, Waleed; Beres, Stephen B; Vuopio, Jaana; Kristinsson, Karl G; Gottfredsson, Magnus; Porter, Adeline R; DeLeo, Frank R; Musser, James M

    2015-09-01

    The identification of the molecular events responsible for strain emergence, enhanced virulence, and epidemicity has been a long-pursued goal in infectious diseases research. A recent analysis of 3,615 genomes of serotype M1 group A Streptococcus strains (the so-called "flesh-eating" bacterium) identified a recombination event that coincides with the global M1 pandemic beginning in the early 1980s. Here, we have shown that the allelic variation that results from this recombination event, which replaces the chromosomal region encoding secreted NADase and streptolysin O, is the key driver of increased toxin production and enhanced infection severity of the M1 pandemic strains. Using isoallelic mutant strains, we found that 3 polymorphisms in this toxin gene region increase resistance to killing by human polymorphonuclear leukocytes, increase bacterial proliferation, and increase virulence in animal models of pharyngitis and necrotizing fasciitis. Genome sequencing of an additional 1,125 streptococcal strains and virulence studies revealed that a highly similar recombinational replacement event underlies an ongoing intercontinental epidemic of serotype M89 group A Streptococcus infections. By identifying the molecular changes that enhance upper respiratory tract fitness, increased resistance to innate immunity, and increased tissue destruction, we describe a mechanism that underpins epidemic streptococcal infections, which have affected many millions of people. PMID:26258415

  10. Streptococcus gordonii modulates Candida albicans biofilm formation through intergeneric communication.

    Science.gov (United States)

    Bamford, Caroline V; d'Mello, Anita; Nobbs, Angela H; Dutton, Lindsay C; Vickerman, M Margaret; Jenkinson, Howard F

    2009-09-01

    The fungus Candida albicans colonizes human oral cavity surfaces in conjunction with a complex microflora. C. albicans SC5314 formed biofilms on saliva-coated surfaces that in early stages of development consisted of approximately 30% hyphal forms. In mixed biofilms with the oral bacterium Streptococcus gordonii DL1, hyphal development by C. albicans was enhanced so that biofilms consisted of approximately 60% hyphal forms. Cell-cell contact between S. gordonii and C. albicans involved Streptococcus cell wall-anchored proteins SspA and SspB (antigen I/II family polypeptides). Repression of C. albicans hyphal filament and biofilm production by the quorum-sensing molecule farnesol was relieved by S. gordonii. The ability of a luxS mutant of S. gordonii deficient in production of autoinducer 2 to induce C. albicans hyphal formation was reduced, and this mutant suppressed farnesol inhibition of hyphal formation less effectively. Coincubation of the two microbial species led to activation of C. albicans mitogen-activated protein kinase Cek1p, inhibition of Mkc1p activation by H(2)O(2), and enhanced activation of Hog1p by farnesol, which were direct effects of streptococci on morphogenetic signaling. These results suggest that interactions between C. albicans and S. gordonii involve physical (adherence) and chemical (diffusible) signals that influence the development of biofilm communities. Thus, bacteria may play a significant role in modulating Candida carriage and infection processes in the oral cavity. PMID:19528215

  11. Serotype-specific mortality from invasive Streptococcus pneumoniae disease revisited

    DEFF Research Database (Denmark)

    Martens, P; Worm, Signe H.Westring

    2004-01-01

    Serotype-specific mortality from invasive Streptococcus pneumoniae disease revisited.Martens P, Worm SW, Lundgren B, Konradsen HB, Benfield T. Department of Infectious Diseases 144, Hvidovre University Hospital, DK-2650 Hvidovre, Denmark. pernillemartens@yahoo.com BACKGROUND: Invasive infection with Streptococcus pneumoniae (pneumococci) causes significant morbidity and mortality. Case series and experimental data have shown that the capsular serotype is involved in the pathogenesis and a determinant of disease outcome. METHODS: Retrospective review of 464 cases of invasive disease among adults diagnosed between 1990 and 2001. Multivariate Cox proportional hazard analysis. RESULTS: After adjustment for other markers of disease severity, we found that infection with serotype 3 was associated with an increased relative risk (RR) of death of 2.54 (95% confidence interval (CI): 1.22-5.27), whereas infection with serotype 1 was associated with a decreased risk of death (RR 0.23 (95% CI, 0.06-0.97)). Additionally, older age, relative leucopenia and relative hypothermia were independent predictors of mortality. CONCLUSION: Our study shows that capsular serotypes independently influenced the outcome from invasive pneumococcal disease. The limitations of the current polysaccharide pneumococcal vaccine warrant the development of alternative vaccines. We suggest that the virulence of pneumococcal serotypes should be considered in the design of novel vaccines.

  12. Meningoencefalitis por Streptococcus pneumoniae resistente: reporte de un caso

    Directory of Open Access Journals (Sweden)

    Olga María Rodríguez Fernández

    2011-01-01

    Full Text Available Introducción: Streptococcus pneumoniae es una bacteria que reside en el aparato respiratorio superior de las personas saludables, pero resulta una infección cuando alcanza localizaciones normalmente estériles, tales como el aparato respiratorio inferior, sistema circulatorio, y sistema nervioso central. Esto ocurre en personas inmunodeprimidas, por diferentes causas. Objetivo: destacar la virulencia de Streptococcus pneumoniae drogo resistente. Caso clínico: niña que llega al hospital por presentar un proceso respiratorio, de varios días de evolución, con fiebre y rinorrea. Ingresó en la sala de Infecciones Respiratorias. Comenzó con deshidratación y somnolencia, por lo que se le realizó una segunda punción lumbar, que resultó con salida de líquido cefalorraquídeo, purulento y presencia de 202 células a predominio de polimorfonucleares, glucosa disminuida, aumento de las proteínas, y Pandy xxxx. La niña se agrava y presenta signos de intenso edema cerebral, con fontanela abombada. Se trató con antimicrobianos como la vancomicina y el ceftriaxone, por varios días. En el laboratorio de Microbiología se confirmó el crecimiento de Streptococccus pneumoniae sensible al meronem que pasa a reemplazar al ceftriaxone. La paciente salió paulatinamente de su gravedad hasta que fue dada de alta con seguimiento y rehabilitación, por presentar secuelas. Conclusiones: este patógeno tan peligroso con sus atributos de virulencia y su elevada resistencia a los antimicrobianos, constituye un fenómeno emergente.

  13. Simultaneous detection of Neisseria meningitidis, Haemophilus influenzae and Streptococcus sp. by polymerase chain reaction for the diagnosis of bacterial meningits / Detecção simultânea da Neisseria meningitidis, Haemophilus influenzae e Streptococcus sp. pela reação em cadeia da polimerase no diagnóstico das meningites bacterianas

    Scientific Electronic Library Online (English)

    Luciane, Failace; Mario, Wagner; Marisa, Chesky; Rosana, Scalco; Luiz Fernando, Jobim.

    2005-12-01

    Full Text Available Avaliamos o desempenho da reação em cadeia da polimerase (PCR) para detecção simultânea da Neisseria meningitidis, Haemophilus influenzae e Streptococcus sp. no diagnóstico das meningites bacterianas e sua aplicabilidade na rotina diagnóstica. Foi realizado um estudo de coorte com 182 crianças apres [...] entando suspeita de meningite bacteriana. Em 84, havia alterações clínicas e laboratoriais sugestivas de meningite bacteriana. Destas, 65 tiveram o agente etiológico identificado pelos métodos laboratoriais de rotina e 19 ficaram sem diagnóstico etiológico. Em 98 pacientes foi excluído o diagnóstico de meningite bacteriana. Analisando o desempenho da PCR encontramos sensibilidade de 88,1%, especificidade de 99,0% e valores preditivos positivo e negativo de 98,7% e 90,1% respectivamente. Nos 19 pacientes com meningite bacteriana mas sem diagnóstico etiológico a PCR detectou microrganismos em 14, sendo 12 N. meningitidis, um H. influenzae e um Streptococcus sp. A PCR possui o potencial de poder aumentar os índices de identificação das técnicas tradicionais, principalmente nas situações onde a microscopia direta, cultura ou identificação antigênica são negativos ou inconclusivos. Abstract in english The simultaneous detection of Neisseria meningitidis, Haemophilus influenzae, and Streptococcus sp. was assessed by polymerase chain reaction (PCR) for the diagnosis of bacterial meningitis, as well as the applicability of PCR as a routine test. A cohort study was carried out with 182 children (2 mo [...] nths to 12 years of age) with suspicion of bacterial meningitis. Routine tests identified the etiologic agent in 65/84 children whose clinical status and laboratory findings suggested the presence of bacterial meningitis. Bacterial meningitis was ruled out in 98 children. In 19 children, the etiologic diagnosis was not possible using standard methods; in 14 of these patients, the etiologic agent was identified by PCR (N. meningitidis=12; H. influenzae=1; Streptococcus sp.=1). The sensitivity of PCR was 88.1%; specificity, 99.0%; positive predictive value, 98.7%; and negative predictive, 90.1%. PCR is a useful complementary diagnostic technique, especially when Gram stain, culture, or antigenic detection are negative or inconclusive.

  14. Antibiogram Sensitivity Pattern of Streptococcus pyogenes and Streptococcus pneumoniae Isolated from Patients with Sore Throat and Pneumonia Infections

    Directory of Open Access Journals (Sweden)

    Uzma Malik

    2005-01-01

    Full Text Available Strains of Streptococcus pyogenes and Streptococcus pneumoniae, isolated from clinical samples (125 throat swabs and 100 sputum from patients suffering from sore throat and pneumonia infections, were subjected to a series of culture sensitivity tests against known antibiotics to determine their antibiogram patterns. Of the S. pyogenes isolates, all were found to be sensitive to penicillin and cefrioxone, whereas some of the strains showed complete resistance against cotrimoxazole (88.9%, oxacillin (22.2%, cephradine (22.2% and erythromycin (11.1%. As for the S. pneumoniae strains, all the isolates in this study were sensitive to vancomycin and cephradine, whereas 80% showed complete resistance to kanamycin, 60% to gentamycin, 20% to cotrimoxazole, 20% to tetracycline and 10% to penicillin. Strains of S. pneumoniae (20% displayed intermediate resistance to erythromycin. Inadequate diagnostic procedures, un-supervised, improper use of antibiotics and easy access to prescription drugs may contribute to the rise of resistant strains. To combat such trends approved strategies must encompass legislative enforcement through strict enforcement of the laws related to sales of prescription drugs, involvement of clinicians, pharmacies and civil society pressure groups to ensure the rational and correct use of prescription drugs.

  15. Meningitis bacteriana por Streptococcus pyogenes: revisión de la literatura / Bacterial meningitis due to Streptococcus pyogenes: literature review

    Scientific Electronic Library Online (English)

    E., Ballesteros Moya; L., Herrera Castillo; L., Escosa García; M.P., Romero González; F., Lázaro Perona; M.I. de, José Gómez.

    2013-12-01

    Full Text Available Introducción: el Streptococcus pyogenes (S. pyogenes) es una etiología poco habitual de meningitis bacteriana a pesar de ser un germen que frecuentemente produce infecciones en otras localizaciones en la edad pediátrica. Material y métodos: se revisaron los casos de bacteriemia por S. pyogenes y los [...] factores de riesgo asociados en la base de datos del Servicio de Microbiología del Hospital Universitario La Paz desde junio de 2002 a junio de 2012. Resultados: únicamente se encontró un caso de bacteremia por S. pyogenes asociado a meningitis, que se describe en este artículo. Conclusiones: a pesar de su baja incidencia, se debe tener en cuenta el S. pyogenes en el diagnóstico diferencial de meningitis bacterianas, especialmente en pacientes con factores de riesgo asociados Abstract in english Introduction: Streptococcus pyogenes (S. pyogenes) is a rare cause of meningitis despite being a common source of pediatric infections in other sites. Material and methods: A search was performed of the pediatric patients with S. pyogenes bacteremia in the microbiology database of the Hospital Infan [...] til La Paz from June 2002 until June 2012. Results: A single case of S. pyogenes meningitis was found and is reported in this article. Conclusions: Despite its low incidence, S. pyogenes should be considered in the differential diagnosis of meningitis, particularly in patients with associated risk factors.

  16. Streptococcus agalactiae em gestantes: prevalência de colonização e avaliação da suscetibilidade aos antimicrobianos Streptococcus agalactiae in pregnant women: prevalence of colonization and antimicrobial susceptibility evaluation

    Directory of Open Access Journals (Sweden)

    Irina Lermontov Borger

    2005-10-01

    Full Text Available OBJETIVOS: verificar a ocorrência de colonização por Streptococcus agalactiae em gestantes e avaliar a suscetibilidade das amostras isoladas aos antimicrobianos. MÉTODOS: foram avaliadas 167 grávidas entre a 32ª e a 41ª semana de gestação, independente da presença ou não de fatores de risco, atendidas no ambulatório de pré-natal entre fevereiro de 2003 e fevereiro de 2004. O material vaginal/anal, colhido com um único swab, foi inoculado em caldo Todd-Hewitt acrescido de ácido nalidíxico (15 µg/mL e gentamicina (8 µg/mL, com posterior subcultura no meio de ágar sangue. A identificação foi feita por meio da avaliação da morfologia e tipo de hemólise das colônias no meio de ágar sangue, teste da catalase, teste de cAMP e testes sorológicos. A avaliação da suscetibilidade aos antimicrobianos foi realizada pelos testes de difusão e de diluição em ágar. A análise estatística foi realizada por meio do teste de chi2; valores de p0,05. Todas as 32 amostras isoladas foram sensíveis a penicilina, cefotaxima, ofloxacina, cloranfenicol, vancomicina e meropenem. A resistência a eritromicina e clindamicina foi detectada em 9,4 e 6,2% das amostras, respectivamente. CONCLUSÕES: a incidência relativamente elevada (19,2% de colonização por S. agalactiae entre as gestantes avaliadas e o isolamento de amostras resistentes, especialmente aos antimicrobianos recomendados nos casos de alergia à penicilina, enfatizam a importância de detectar esta colonização no final da gravidez, associada à avaliação da suscetibilidade aos antimicrobianos, para uma prevenção eficaz da infecção neonatal.PURPOSE: to verify the occurrence of colonization by Streptococcus agalactiae in pregnant women attended at the prenatal outpatient clinic of the Teaching Maternity Hospital of Rio de Janeiro University (UFRJ and to evaluate the susceptibility of the isolates to antimicrobial agents. METHODS: a total of 167 pregnant women between the 32nd and 41st week of gestation, regardless of risk factors, attended at the antenatal clinic between February 2003 and February 2004, were evaluated. The vaginal/anal material, collected by the same swab, was inoculated in Todd-Hewitt broth to which nalidixic acid (15 µg/mL and gentamicin (8 µg/mL were added, with following subcultures onto sheep blood-agar. Identification was carried out observing colony morphology and beta-hemolysis type on blood-agar, catalase, cAMP, and serological tests. The antimicrobial susceptibility testing used agar diffusion and agar dilution methods. Statistical analysis was performed by the chi2 test with the level of significance set at p0.05. All 32 isolated strains were susceptible to penicillin, cefotaxime, ofloxacin, chloramphenicol, vancomycin and meropenem. Resistance to erythromycin and clindamycin was detected in 9.4 and 6.2% of the isolates, respectively. CONCLUSIONS: the relatively high incidence (19.2% of colonization by S. agalactiae among the evaluated pregnant women and the recovery of antimicrobial resistant strains, especially those recommended in cases of penicillin allergy, emphasize the importance, for a correct prevention of neonatal infections, of detecting colonization at the end of pregnancy and evaluating antimicrobial susceptibility.

  17. Streptococcus agalactiae em gestantes: prevalência de colonização e avaliação da suscetibilidade aos antimicrobianos / Streptococcus agalactiae in pregnant women: prevalence of colonization and antimicrobial susceptibility evaluation

    Scientific Electronic Library Online (English)

    Irina Lermontov, Borger; Rachel Elise Cerqueira, d' Oliveira; Angela Christina Dias de, Castro; Silvia Susana Bona de, Mondino.

    2005-10-01

    Full Text Available OBJETIVOS: verificar a ocorrência de colonização por Streptococcus agalactiae em gestantes e avaliar a suscetibilidade das amostras isoladas aos antimicrobianos. MÉTODOS: foram avaliadas 167 grávidas entre a 32ª e a 41ª semana de gestação, independente da presença ou não de fatores de risco, atendid [...] as no ambulatório de pré-natal entre fevereiro de 2003 e fevereiro de 2004. O material vaginal/anal, colhido com um único swab, foi inoculado em caldo Todd-Hewitt acrescido de ácido nalidíxico (15 µg/mL) e gentamicina (8 µg/mL), com posterior subcultura no meio de ágar sangue. A identificação foi feita por meio da avaliação da morfologia e tipo de hemólise das colônias no meio de ágar sangue, teste da catalase, teste de cAMP e testes sorológicos. A avaliação da suscetibilidade aos antimicrobianos foi realizada pelos testes de difusão e de diluição em ágar. A análise estatística foi realizada por meio do teste de chi2; valores de p0,05). Todas as 32 amostras isoladas foram sensíveis a penicilina, cefotaxima, ofloxacina, cloranfenicol, vancomicina e meropenem. A resistência a eritromicina e clindamicina foi detectada em 9,4 e 6,2% das amostras, respectivamente. CONCLUSÕES: a incidência relativamente elevada (19,2%) de colonização por S. agalactiae entre as gestantes avaliadas e o isolamento de amostras resistentes, especialmente aos antimicrobianos recomendados nos casos de alergia à penicilina, enfatizam a importância de detectar esta colonização no final da gravidez, associada à avaliação da suscetibilidade aos antimicrobianos, para uma prevenção eficaz da infecção neonatal. Abstract in english PURPOSE: to verify the occurrence of colonization by Streptococcus agalactiae in pregnant women attended at the prenatal outpatient clinic of the Teaching Maternity Hospital of Rio de Janeiro University (UFRJ) and to evaluate the susceptibility of the isolates to antimicrobial agents. METHODS: a tot [...] al of 167 pregnant women between the 32nd and 41st week of gestation, regardless of risk factors, attended at the antenatal clinic between February 2003 and February 2004, were evaluated. The vaginal/anal material, collected by the same swab, was inoculated in Todd-Hewitt broth to which nalidixic acid (15 µg/mL) and gentamicin (8 µg/mL) were added, with following subcultures onto sheep blood-agar. Identification was carried out observing colony morphology and beta-hemolysis type on blood-agar, catalase, cAMP, and serological tests. The antimicrobial susceptibility testing used agar diffusion and agar dilution methods. Statistical analysis was performed by the chi2 test with the level of significance set at p0.05). All 32 isolated strains were susceptible to penicillin, cefotaxime, ofloxacin, chloramphenicol, vancomycin and meropenem. Resistance to erythromycin and clindamycin was detected in 9.4 and 6.2% of the isolates, respectively. CONCLUSIONS: the relatively high incidence (19.2%) of colonization by S. agalactiae among the evaluated pregnant women and the recovery of antimicrobial resistant strains, especially those recommended in cases of penicillin allergy, emphasize the importance, for a correct prevention of neonatal infections, of detecting colonization at the end of pregnancy and evaluating antimicrobial susceptibility.

  18. MOBILE AGENT: EMERGING TECHNOLOGY

    Directory of Open Access Journals (Sweden)

    RAJGURU P. V. DR. DESHMUKH S. D

    2011-12-01

    Full Text Available Mobile agent technology has been promoted as an emerging technology that makes it much easier to design, implement, and maintain distributed systems, introduction to basic concepts of mobile agents like agent mobility, agent types and places and agent communication. Then benefits of the usage of mobile agents are summarized and illustrated by selected applications. The next section lists requirements and desirable properties for mobile agent languages and systems. We study the main features, challenges, and open problems of mobile agent technology.

  19. Sepsis neonatal por Estreptococos Pyogenes / Neonatal Sepsis by Streptococcus pyogenes

    Scientific Electronic Library Online (English)

    Gilberto, Rodríguez-Herrera; Cinthya, Ramírez-Navarro.

    2009-09-01

    Full Text Available Se presenta el caso de un paciente masculino, recién nacido a término adecuado para la edad gestacional, quien nace por parto vaginal, con el antecedente de fiebre en la madre durante el periodo de postparto inmediato. Los padres consultan a los 2 días de vida pues le notan dificultad respiratoria, [...] hipoactividad y rechazo a la leche materna. El paciente se interna y se aborda como una sepsis. Durante su estancia en el servicio de neonatología del Hospital Nacional de Niños asocia fallo respiratorio que amerita ventilación mecánica asistida por varios días en diferentes ocasiones, derrame pleural exudativo, convulsiones de origen hipóxico isquémico. Con reporte de hemocultivos positivos por Estreptococos pyogenes. El Estreptococos pyogenes o estreptococo ?-hemol?tico del grupo A, fue un problema en los comienzos del siglo pasado, siendo frecuente en las infecciones puerperales y del reci?n nacido. En la actualidad es un germen sumamente raro en los procesos de sepsis neonatal.2 La gravedad de la enfermedad causada por este microorganismo en el periodo neonatal var?a desde una onfalitis crónica de bajo grado a una septicemia, una meningitis fulminante y la muerte.1 El presente artículo pretende hacer un resumen del paciente, con su evolución clínica, radiológica y además ejemplificar todas las complicaciones que tuvimos con este germen tan poco frecuente en la actualidad en sepsis neonatal. Abstract in english We present herein the case of a newborn patient of appropriate gestational age weight ( 3700 grams), born by vaginal delivery, from a mother that had had 2 previous pregnancies (2 normal deliveries). During the immediate puerperium she had fever. The parents consulted at the age of 2 days, stating t [...] hat they had noticed difficult breathing since his birth, hipoactivity and poor appetite. He was admitted to the hospital and underwent several studies searching for the origin and germ causing the sepsis. He developed respiratory failure and needed mechanical ventilation for several days on different occasions. He had exudative pleural effusion and hypoxic ischemic seizures. Later on, his blood cultures were positive for Streptococcus pyogenes. Streptococcus pyogenes or Streptococcus ?- hemolytic group A infection, used to be a common entity in the beginning of the past century, it was commonly associated with puerperal infections and newborn infections, but its incidence declined and nowadays, is uncommon during the neonatal period. Its clinical manifestations could vary from chronic omphalitis up to a low grade septicemia or fulminant meningitis. Since its incidence has declined, at the present time; is an unusual infection of the neonatal period. Ampicillin and gentamicin are currently recommended as first-line antimicrobials, ampicillin replacing the previously recommended penicillin.

  20. Infecciones tisulares por Streptococcus ß-hemolítico grupo A en Hospital Regional de Talca / Tissue infections caused by group A ß hemolytic Streptococcus in a Regional Chilean Hospital

    Scientific Electronic Library Online (English)

    Sandra, Hasbún A; Héctor, Arias P; Roberto, Tapia R.

    2000-11-01

    Full Text Available [...] Abstract in english Background: A resurgence of group A ß hemolytic Streptococcus infections such as fasciitis, cellulitis and Strptococcal Toxic Syndrome has been observed recently. Aim: To study the clinical features of patients with group A ß hemolytic Streptococcus infections in a regional hospital. Patients and me [...] thods: Retrospective review of medical records of patients notified as having a group A ß hemolytic Streptococcus tissue infection, between 1994 and 1999. Results: twenty four patients were notified in the period as having a group A ß hemolytic Streptococcus infection and 18 (13 male, mean age 39 tears old) had tissue involvement. Eleven patients had a fasciitis (61%), six had a cellulitis (33%) and 14 patients (77%), a Streptococcal Toxic Shock Syndrome. Eight patients died during hospital stay. The infection portal of entry was identify in 13 patients (the skin in 10 and intramuscular injections in three). Deceased patients had a longer lapse of disease before admission than patients discharged alive (5(range 3h-7 days) and 2.1 (range 6h-5 days) respectively). In seven patients a quick serological test, designed for pharyngeal infections was performed and it was positive in five. Blood cultures were positive in seven patients and in 11, the germ was isolated from the lesions. Conclusions: As the early diagnosis of group A ß hemolytic Streptococcus tissue infections has a prognostic value, the population should be instructed to recognize early signs and symptoms of these infections (Rev Méd Chile 2000; 128: 1215-19)

  1. Impacto de la enfermedad por Streptococcus pneumoniae en población adulta mayor en Bogotá, Colombia, 2008 / The impact of pneumococcal disease on adults living in Bogota, Colombia, 2008

    Scientific Electronic Library Online (English)

    Carlos, Castañeda-Orjuela; Nelson, Alvis-Guzmán; Fernando, de la Hoz-Restrepo.

    2010-02-01

    Full Text Available Objetivo Estimar el impacto de la enfermedad por Streptococcus pneumoniae en la población mayor de 60 años en Bogotá D.C. Colombia. Métodos Se realizó un estudio de impacto de enfermedad por neumococo combinando una búsqueda sistemática de literatura con el análisis de fuentes de datos rutinarios de [...] mortalidad, consultas y hospitalizaciones debidas neumonías y meningitis en adultos mayores de 60 años. Resultados Se estimó para 2008 en la población bogotana mayor de 60 años la ocurrencia de 6 585 neumonías por todos los agentes, 689 debidas a Streptococcus pneumoniae, y 73 meningitis, 12 producidas por neumococo. El total de muertes por neumonías se estimó en 1 910, 82 atribuibles al neumococo, y de las 40 muertes por meningitis, 7 habrían ocurrido en casos de meningitis neumocócicas. Conclusiones El impacto de la enfermedad debida a neumococo en población mayor de 60 años en Bogotá justifica la consideración de estrategias específicas de prevención tales como la vacunación. Abstract in english Objective Estimating the impact of pneumococcal disease amongst adults living in Bogota, Colombia Methods The impact of pneumococcal disease was studied by combining a systematic literature search with analysing routine sources regarding mortality, consultation and hospitalisation dates due to pneum [...] onia and meningitis. Results The occurrence of 6,585 cases of pneumonia by all germs was estimated for 2008 in the adult population aged over 60, 689 cases being due to Streptococcus pneumonia, and 73 cases of meningitis, plus 12 cases caused by pneumococcus. The total of deaths from pneumonia was estimated to be 1,910 cases (82 due to pneumonia) and 40 deaths occurred from meningitis (7 of these cases being due to pneumococcal meningitis). Conclusiones The impact of pneumococcal disease in adults aged over 60 in Bogota (only taking into account cases of meningitis and pneumonia with blood and CSF isolates) justifies considering specific prevention strategies such as vaccination.

  2. Impacto de la enfermedad por Streptococcus pneumoniae en población adulta mayor en Bogotá, Colombia, 2008 The impact of pneumococcal disease on adults living in Bogota, Colombia, 2008

    Directory of Open Access Journals (Sweden)

    Carlos Castañeda-Orjuela

    2010-02-01

    Full Text Available Objetivo Estimar el impacto de la enfermedad por Streptococcus pneumoniae en la población mayor de 60 años en Bogotá D.C. Colombia. Métodos Se realizó un estudio de impacto de enfermedad por neumococo combinando una búsqueda sistemática de literatura con el análisis de fuentes de datos rutinarios de mortalidad, consultas y hospitalizaciones debidas neumonías y meningitis en adultos mayores de 60 años. Resultados Se estimó para 2008 en la población bogotana mayor de 60 años la ocurrencia de 6 585 neumonías por todos los agentes, 689 debidas a Streptococcus pneumoniae, y 73 meningitis, 12 producidas por neumococo. El total de muertes por neumonías se estimó en 1 910, 82 atribuibles al neumococo, y de las 40 muertes por meningitis, 7 habrían ocurrido en casos de meningitis neumocócicas. Conclusiones El impacto de la enfermedad debida a neumococo en población mayor de 60 años en Bogotá justifica la consideración de estrategias específicas de prevención tales como la vacunación.Objective Estimating the impact of pneumococcal disease amongst adults living in Bogota, Colombia Methods The impact of pneumococcal disease was studied by combining a systematic literature search with analysing routine sources regarding mortality, consultation and hospitalisation dates due to pneumonia and meningitis. Results The occurrence of 6,585 cases of pneumonia by all germs was estimated for 2008 in the adult population aged over 60, 689 cases being due to Streptococcus pneumonia, and 73 cases of meningitis, plus 12 cases caused by pneumococcus. The total of deaths from pneumonia was estimated to be 1,910 cases (82 due to pneumonia and 40 deaths occurred from meningitis (7 of these cases being due to pneumococcal meningitis. Conclusiones The impact of pneumococcal disease in adults aged over 60 in Bogota (only taking into account cases of meningitis and pneumonia with blood and CSF isolates justifies considering specific prevention strategies such as vaccination.

  3. Effects of Salts and Metal Oxides on Electrochemical and Optical Properties of Streptococcus mutans

    Science.gov (United States)

    Kawai, Tsuyoshi; Nagame, Seigo; Kambara, Masaki; Yoshino, Katsumi

    1994-10-01

    The effects of calcium salts and metal oxide powders on electrochemical, optical and biological properties of Streptococcus mutans have been studied as a novel method to determine the strain. Electrochemical signals of Streptococcus mutans show remarkable decrease in the presence of saturated calcium salts such as CaHPO4, Ca3(PO4)2, and Ca5(PO4)3OH depending on the strains of Streptococcus mutans: Ingbritt, NCTC-10449, or GS-5. The number of viable cells also decreases upon addition of these powders. The effects of metal oxides such as ZnO and BaTiO3 on the electrochemical characteristics and photoluminescence of Streptococcus mutans have also been studied.

  4. Expression of the Streptococcus mutans fructosyltransferase gene within a mammalian host.

    OpenAIRE

    Grey, W T; Curtiss, R; Hudson, M C

    1997-01-01

    In vivo expression of the virulence-associated fructosyltransferase gene (ftf) of Streptococcus mutans has been examined. S. mutans ftf expression is affected by both the specific carbohydrate consumed and the age of the host animal.

  5. High-frequency conjugation associated with Streptococcus lactis donor cell aggregation.

    OpenAIRE

    Gasson, M. J.; Davies, F. L.

    1980-01-01

    Conjugal transfer of the Streptococcus lactis 712 lactose plasmid was found to occur at a low frequency. Variants of this plasmid were selected which had much greater donor abilities and which also exhibited an unusual cell aggregation phenotype.

  6. 77 FR 26014 - Prospective Grant of Exclusive License: P4 Peptide From Streptococcus Pneumoniae

    Science.gov (United States)

    2012-05-02

    ...Use of P4 as either a carrier and/or immunoenhancer in a polysaccharide vaccine conjugate for prevention of Streptococcus pneumonia infection in humans'') to practice the inventions embodied in the patent application referred to below to Viper...

  7. Interferon-? inhibits group B Streptococcus survival within human endothelial cells

    Directory of Open Access Journals (Sweden)

    Viviane de Oliveira Freitas Lione

    2014-11-01

    Full Text Available Endothelial dysfunction is a major component of the pathophysiology of septicaemic group B Streptococcus (GBS infections. Although cytokines have been shown to activate human umbilical vein endothelial cells (HUVECs, the capacity of interferon (IFN-? to enhance the microbicidal activity of HUVECs against GBS has not been studied. We report that the viability of intracellular bacteria was reduced in HUVECs activated by IFN-?. Enhanced fusion of lysosomes with bacteria-containing vacuoles was observed by acid phosphatase and the colocalisation of Rab-5, Rab-7 and lysosomal-associated membrane protein-1 with GBS in IFN-?-activated HUVECs. IFN-? resulted in an enhancement of the phagosome maturation process in HUVECs, improving the capacity to control the intracellular survival of GBS.

  8. Streptococcus pyogenes degrades extracellular matrix in chondrocytes via MMP-13

    International Nuclear Information System (INIS)

    Group A streptococcus (GAS) causes a wide range of human diseases, including bacterial arthritis. The pathogenesis of arthritis is characterized by synovial proliferation and the destruction of cartilage and subchondral bone in joints. We report here that GAS strain JRS4 invaded a chondrogenic cell line ATDC5 and induced the degradation of the extracellular matrix (ECM), whereas an isogenic mutant of JRS4 lacking a fibronectin-binding protein, SAM1, failed to invade the chondrocytes or degrade the ECM. Reverse transcription-PCR and Western blot analysis revealed that the expression of matrix metalloproteinase (MMP)-13 was strongly elevated during the infection with GAS. A reporter assay revealed that the activation of the AP-1 transcription factor and the phosphorylation of c-Jun terminal kinase participated in MMP-13 expression. These results suggest that MMP-13 plays an important role in the destruction of infected joints during the development of septic arthritis

  9. Characterization of a bacteriocin produced by Streptococcus thermophilus 81.

    Science.gov (United States)

    Ivanova, I; Miteva, V; Stefanova, Ts; Pantev, A; Budakov, I; Danova, S; Moncheva, P; Nikolova, I; Dousset, X; Boyaval, P

    1998-07-21

    A new bacteriocin, produced by Streptococcus thermophilus 81 has been isolated, purified and characterized. By its heat sensitivity and broad inhibitory spectrum it does not resemble any other S. thermophilus bacteriocin. The mode of action is bacteriostatic. This peptide of 32 amino acids is efficient against several Bacillus species, Listeria monocytogenes, Salmonella typhimurium, Escherichia coli, Yersinia pseudotuberculosis and Yersinia enterocolitica. This bacteriocin is heat labile but its activity was not altered by pH variation from 3 to 10. Six months of storage at 40 degrees C did not influence the activity. The inactivation by detergents and the inability to resolve the protein in SDS-PAGE supposes a more complex structure or a possible stabilizing effect of other molecules. The low sensitivity of Lactobacillus delbrueckii subsp. bulgaricus to the isolated bacteriocin suggests that S. thermophilus 81 may be used in yoghurt starters. PMID:9728685

  10. [Primary peritonitis due to Streptococcus pneumoniae in childhood].

    Science.gov (United States)

    van Houten, M A; Ab, E; Zwierstra, R P; Kimpen, J L

    1998-04-01

    Three patients, two boys of 5 months and 6 years and one girl aged 4 years, presented with acute abdominal pain, vomiting and fever, suggesting peritonitis. Imaging examinations (abdominal survey roentgenogram and (or) echography), exploratory laparotomy (in two patients) and blood cultures with growth of Streptococcus pneumoniae led to the diagnosis of primary peritonitis. Intravenous antibiotics led to recovery, in one patient complicated by paralytic ileus, which was treated surgically. Primary peritonitis is a rare condition which should be considered in the differential diagnosis of children with an acute abdominal syndrome. Conditions requiring surgery should be excluded by imaging examinations or laparotomy. When the diagnosis is confirmed by paracentesis or laparotomy, antibiotic treatment has to be started. PMID:9646612

  11. Treatment of Streptococcus mutans bacteria by a plasma needle

    Science.gov (United States)

    Zhang, Xianhui; Huang, Jun; Liu, Xiaodi; Peng, Lei; Guo, Lihong; Lv, Guohua; Chen, Wei; Feng, Kecheng; Yang, Si-ze

    2009-03-01

    A dielectric barrier discharge plasma needle was realized at atmospheric pressure with a funnel-shaped nozzle. The preliminary characteristics of the plasma plume and its applications in the inactivation of Streptococcus mutans (S. mutans), the most important microorganism causing dental caries, were presented in this paper. The temperature of the plasma plume does not reach higher than 315 K when the power is below 28 W. Oxygen was injected downstream in the plasma afterglow region through the powered steel tube. Its effect was studied via optical-emission spectroscopy, both in air and in agar. Results show that addition of 26 SCCM O2 does not affect the plume length significantly (SCCM denotes cubic centimeter per minute at STP). The inactivation of S. mutans is primarily attributed to ultraviolet light emission, O, OH, and He radicals.

  12. Interferon-? inhibits group B Streptococcus survival within human endothelial cells

    Scientific Electronic Library Online (English)

    Viviane de Oliveira Freitas, Lione; Michelle Hanthequeste Bittencourt dos, Santos; Jessica Silva Santos de, Oliveira; Ana Luiza, Mattos-Guaraldi; Prescilla Emy, Nagao.

    2014-11-01

    Full Text Available Endothelial dysfunction is a major component of the pathophysiology of septicaemic group B Streptococcus (GBS) infections. Although cytokines have been shown to activate human umbilical vein endothelial cells (HUVECs), the capacity of interferon (IFN)-? to enhance the microbicidal activity of HUVECs [...] against GBS has not been studied. We report that the viability of intracellular bacteria was reduced in HUVECs activated by IFN-?. Enhanced fusion of lysosomes with bacteria-containing vacuoles was observed by acid phosphatase and the colocalisation of Rab-5, Rab-7 and lysosomal-associated membrane protein-1 with GBS in IFN-?-activated HUVECs. IFN-? resulted in an enhancement of the phagosome maturation process in HUVECs, improving the capacity to control the intracellular survival of GBS.

  13. The effect of xylitol on Streptococcus mutans in children.

    Science.gov (United States)

    Massoth, Dominique; Massoth, Gabrielle; Massoth, I Richard; Laflamme, Lise; Shi, Wenyuan; Hu, Chuhong; Gu, Fang

    2006-03-01

    A study was performed on 91 second-grade students from the Los Angeles Unified School District to test the effects of xylitol chewing gum on Streptococcus mutans in the saliva. Saliva was collected from students and tested for the first time using the new University of California, Los Angeles, monoclonal antibody testing method. Students found to have moderate or high levels of salivary S. mutans were administered four tablets/day of xylitol gum for three weeks. The levels of S. mutans in the saliva of children in the high caries index subgroup decreased by 61.7 percent. Xylitol can be dispensed in a public school setting by school nurses and can be a very safe, efficient and inexpensive preventative measure for children at high risk for dental caries. PMID:16895079

  14. Atypical presentation of thoracic spondylodiscitis caused by Streptococcus mitis.

    Science.gov (United States)

    Cariati, Vincent P; Deng, Wu

    2014-01-01

    Spondylodiscitis, which is most commonly caused by Staphylococcus aureus, is an uncommon infection in adults. The diagnosis of spondylodiscitis is often delayed by its vague and non-specific presentations. As part of the normal flora in human mouth and sinuses, Streptococcus mitis is a very rare cause of spondylodiscitis. We report a case of thoracic spondylodiscitis caused by S. mitis in a patient with chronic sinusitis. The patient atypically presented with a sharp chest pain that radiated to the back and the imaging studies were initially negative. He failed outpatient pain management and the diagnosis of spondylodiscitis was confirmed by bone biopsy 6?weeks later. Treatment with antibiotics completely alleviated the pain. Increased awareness and a high index of suspicion are essential for early diagnosis of spondylodiscitis with an atypical presentation. PMID:24842345

  15. Streptococcus iniae, a bacterial infection in barramundi Lates calcarifer.

    Science.gov (United States)

    Bromage, E S; Thomas, A; Owens, L

    1999-05-31

    The cause of ongoing mortality in barramundi Lates calcarifer (Bloch) in seawater culture was identified as Streptococcus iniae by biochemical and physiological tests. This is the first published record of this bacterial species in Australia and the first confirmed report of S. iniae causing mortality in barramundi. The bacterium was highly pathogenic for barramundi when challenged by bath exposure. The pathogen was found to have a LD50 of 2.5 x 10(5) and 3.2 x 10(4) colony-forming units at 48 h and 10 d respectively. Experimental challenge of barramundi resulted in high levels of mortality (> 40%) within a 48 h period. Ten days after the challenge, S. iniae could not be isolated from kidney, spleen, liver or eye of surviving fish. However, the organism was easily isolated from the brain of both moribund and healthy fish, indicating that barramundi can carry the bacterium asymptomatically. PMID:10401583

  16. Pericardite em suínos ao abate no Rio Grande Sul: avaliação de agentes bacterianos e lesões associadas / Bacterial agents and lesions associated with pericarditis in slaughter pigs in Rio Grande do Sul, Brazil

    Scientific Electronic Library Online (English)

    Carolini F., Coelho; Priscila, Zlotowski; Caroline P. de, Andrade; Sandra M., Borowski; Thaís S., Gaggini; Laura L. de, Almeida; David, Driemeier; David E.S.N. de, Barcellos.

    2014-07-01

    Full Text Available O objetivo do presente estudo foi identificar a frequência de lesões macroscópicas e microscópicas e dos agentes bacterianos envolvidos em pericardites em suínos no abate no Estado do Rio Grande do Sul. As amostras foram coletadas em frigoríficos de suínos com Serviço de Inspeção Federal (SIF) entre [...] fevereiro a outubro de 2010 e a condenação por pericardite dos animais acompanhados foi de 3,9% (299/7.571). No total foram investigados 91 casos de pericardites, 89% deles foram classificados como crônicos por histopatologia e pleurite crônica foi observada em 47% dos pulmões correspondentes, todavia não houve associação significativa entre as duas lesões. Os agentes bacterianos isolados a partir dos corações foram Streptococcus spp., Pasteurella multocida, Haemophilus parasuis e Streptococcus suis. DNA bacterianos mais detectados pela PCR foram de Mycoplasma hyopneumoniae e Actinobacillus pleuropneumoniae. Houve associação significativa entre isolamento de P. multocida e Streptococcus sp. nos corações e pulmões correspondentes. Esses resultados sugerem que a infecção no pulmão possa ter servido de porta de entrada para a colonização do pericárdio adjacente. Apesar de M. hyopneumoniae ter sido o agente detectado com maior frequência pela PCR em corações e pulmões correspondentes, não houve associação significativa da detecção dos agentes nos órgãos. Isto sugere que as infecções foram eventos independentes. Os demais agentes investigados não apresentaram associação significativa entre isolamento ou detecção de DNA em coração e pulmão correspondente. Outro achado importante foi a presença de coinfecções bacterianas em 2% dos corações e por PCR foi detectado DNA bacteriano de dois ou mais agentes em 16,5% dos corações. Esses resultados sugerem que as coinfecções em pericardites precisam ser melhor estudadas. Abstract in english The objective of the study was to identify the frequency of macroscopic and microscopic lesions and bacterial agents involved with pericarditis in slaughter pigs in the State of Rio Grande do Sul, Brazil. The samples were collected in slaughterhouses with Federal Inspection Service (SIF) between Feb [...] ruary and October, 2010. Condemnation due to pericarditis in the examined animals was 3.9% (299/7,571). Ninety one cases of pericarditis were examined and by histopathology 89% were chronic and 47% of the corresponding lungs showed chronic pleuritis, but there was no significant association between both lesions. The bacterial agents isolated from the hearts were Streptococcus spp., Pasteurella multocida, Haemophilus parasuis and Streptococcus suis. Bacterial DNA from Mycoplasma hyopneumoniae and Actinobacillus pleuropneumoniae were the most frequently detected by PCR. There was significant association between isolation of P. multocida and Streptococcus spp. in the hearts and corresponding lungs. The results suggest that lung infection could act as a port of entry to the colonization of the adjacent pericardium. In spite of the fact that M. hyopneumoniae was the agent more frequently identified by PCR in the heart and corresponding lung, there was no significant association of the agent in the organs. This suggests that the infections were independent events. The other agents investigated did not show significant association between isolation or DNA detection in heart and corresponding lungs. Another important finding was the presence of coinfection between bacterial agents in 2% of the hearts and by PCR were identified bacterial DNA of two or more agents in 16.5% of the hearts. These results suggest that coinfections in cases of pericarditis need further investigation.

  17. Group B streptococcus neonatal invasive infections, France 2007-2012.

    Science.gov (United States)

    Joubrel, C; Tazi, A; Six, A; Dmytruk, N; Touak, G; Bidet, P; Raymond, J; Trieu Cuot, P; Fouet, A; Kernéis, S; Poyart, C

    2015-10-01

    Streptococcus agalactiae (group B streptococcus (GBS)) is the leading cause of invasive infections among newborns in industrialized countries, with two described syndromes: early-onset disease (EOD) and late-onset disease (LOD). Since the introduction in many countries of intrapartum antibioprophylaxis (IAP), the incidence of EOD has dramatically decreased, whereas that of LOD remains unchanged. We describe the clinical and bacteriological characteristics of 438 GBS neonatal invasive infections notified to the French National Reference Centre for Streptococci in France from 2007 to 2012. Clinical data were retrieved from hospitalization reports or questionnaires. Capsular type, assignment to the hypervirulent clonal complex (CC)17 and antibiotic susceptibility profiles were determined. One hundred and seventy-four (39.7%) and 264 (60.3%) isolates were responsible for EOD, including death in utero, and LOD, respectively. EOD was associated with bacteraemia (n = 103, 61%) and LOD with meningitis (n = 145, 55%). EOD was mainly due to capsular polysaccharide (CPS) III isolates (n = 99, 57%) and CPS Ia isolates (n = 40, 23%), and CPS III isolates were responsible for 80% (n = 211) of LOD cases. CC17 accounted for 80% (n = 121) of CPS III isolates responsible for meningitis (n = 151; total cases of meningitis, 188). Bad outcome risk factors were low gestational age and low birthweight. LOD represents almost 60% of cases of neonatal GBS disease in France and other countries in which IAP has been implemented. This observation reinforces the need to develop new prevention strategies targeting CC17, which is predominant in GBS neonatal infections. PMID:26055414

  18. Zinc disrupts central carbon metabolism and capsule biosynthesis in Streptococcus pyogenes

    OpenAIRE

    Ong, Cheryl-Lynn Y.; Walker, Mark J; McEwan, Alastair G

    2015-01-01

    Neutrophils release free zinc to eliminate the phagocytosed bacterial pathogen Streptococcus pyogenes (Group A Streptococcus; GAS). In this study, we investigated the mechanisms underpinning zinc toxicity towards this human pathogen, responsible for diseases ranging from pharyngitis and impetigo, to severe invasive infections. Using the globally-disseminated M1T1 GAS strain, we demonstrate that zinc stress impairs glucose metabolism through the inhibition of the glycolytic enzymes phosphofruc...

  19. CAMP Factor is Not Essential for Systemic Virulence of Group B Streptococcus

    OpenAIRE

    Hensler, Mary E.; Quach, Darin; Hsieh, Chia-Jun; Doran, Kelly S; Nizet, Victor

    2007-01-01

    The Gram-positive pathogen Group B Streptococcus (GBS) is the leading cause of bacterial pneumonia, sepsis, and meningitis in human newborns. GBS elaborates a pore-forming toxin known as CAMP factor that synergizes with Staphylococcus aureus ?-toxin, generating a co-hemolytic reaction useful in identification of GBS in the clinical laboratory. To evaluate the indirect evidence implicating CAMP factor in Group B Streptococcus (GBS) pathogenesis, the cfb gene encoding the pore-forming cytotoxin...

  20. Colonization Rate of Group B Streptococcus (GBS) in Pregnant Women Using GBS Agar Medium

    OpenAIRE

    Fatemi F; Chamani L; Pakzad P; Zeraati H; Rabbani H; Asgari S

    2009-01-01

    Group B streptococci (GBS) or Streptococcus agalactiae are members of the normal flora of the female genital tract. GBS normally colonizes the vagina in many women asymptomatically. During labor this organism may infect the newborn, leading to neonatal sepsis and meningitis. This study aimed to investigate the prevalence of group B streptococcus in pregnant women by a rapid and easy culture method. It seems that in cases in which GBS carriage is not suspected until the time of labor, using su...

  1. Characterization of -hemolytic Streptococcus Strains Isolated from Patients of Severe Invasive Streptococcal Infections

    OpenAIRE

    Tadayoshi Ikebe; Haruo Watanabe

    2005-01-01

    Streptococcus pyogenes (group A streptococcus) is one of the most common human pathogens. It causes a wide array of infections, the most frequent of which is acute pharyngitis (strep throat). From the late 1980s, Streptococcal Toxic Shock-like Syndrome (STSS) caused by S. pyogenes became a serious problem in both developed and developing countries. Symptoms such as pharyngitis, fever and pain may suddenly develop and the disease may progress very rapidly in some patients to soft tissue necros...

  2. Streptococcus pneumoniae resistance to penicillin and ceftriaxone in a tertiary care center in Saudi Arabia.

    OpenAIRE

    Ahmed A. Al-Aqeeli; Guy, Mary L.; Suliman A. Al-Jumaah

    2002-01-01

    OBJECTIVES The proportion of penicillin and ceftriaxone resistant Streptococcus pneumoniae isolates and associated risk factors varies by geographic areas in the world. We conducted a retrospective study to determine the extent of penicillin and ceftriaxone non-susceptible Streptococcus pneumoniae bacteremia in a tertiary care medical center in the city of Riyadh, Kingdom of Saudi Arabia. METHODS We reviewed 172 episodes of Streptrococcus pneumoniae bacteremic diseases involving 160 ...

  3. Streptococcus agalactiae in adults at chiang mai university hospital: a retrospective study

    OpenAIRE

    Sirisanthana Thira; Nuntachit Nontakan; Bunchoo Manasanant; Jullaket Waree; Chaiwarith Romanee; Supparatpinyo Khuanchai

    2011-01-01

    Abstract Background Infection caused by Streptococcus agalactiae, a Group B streptococcus, is an emerging disease in non-pregnant adults. This study describes the epidemiological, clinical, and microbiological characteristics of S. agalactiae infection in adult patients in northern Thailand. Methods A retrospective study was conducted between January 1, 2006 and December 31, 2009 at Chiang Mai University Hospital among patients aged ?15 years, whose clinical specimens obtained from normally s...

  4. Oral immunization with PspA elicits protective humoral immunity against Streptococcus pneumoniae infection.

    OpenAIRE

    Yamamoto, M; McDaniel, L. S.; Kawabata, K.; Briles, D E; Jackson, R J; McGhee, J R; Kiyono, H

    1997-01-01

    Streptococcus pneumoniae is a major respiratory mucosal pathogen affecting infants and children. Although a polysaccharide-based vaccine has been useful in adult populations, it does not elicit protective immunity in infants and young children. Pneumococcal surface protein A (PspA) is a highly immunogenic surface protein produced by all strains of Streptococcus pneumoniae. Previous studies have shown that systemic immunization of mice with PspA can elicit protective immunity against fatal pne...

  5. Detection of diacetyl (caramel odor) in presumptive identification of the "Streptococcus milleri" group.

    OpenAIRE

    Chew, T A; Smith, J.M

    1992-01-01

    The caramel odor associated with the "Streptococcus milleri" group was shown to be attributable to the formation of the metabolite diacetyl. Levels of diacetyl in the 22- to 200-mg/liter range were produced by 68 strains of the "S. milleri" group; apart from one strain of Streptococcus mutans, all 92 other strains of streptococci belonging to 12 species produced < 13 mg of diacetyl per liter. Quantitation of diacetyl levels from cultures of streptococci is suggested as a rapid presumptive tes...

  6. Capsular Gene Typing of Streptococcus agalactiae Compared to Serotyping by Latex Agglutination

    DEFF Research Database (Denmark)

    Yao, Kaihu; Poulsen, Knud; Maione, Domenico; Rinaudo, C Daniela; Baldassarri, Lucilla; Telford, John L; Sørensen, Uffe B Skov; Kilian, Mogens

    2013-01-01

    We evaluated three different PCR-based capsular gene typing methods applied to 312 human and bovine Streptococcus agalactiae (group B Streptococcus [GBS]) isolates and compared the results to serotyping results obtained by latex agglutination. Among 281 human isolates 27% could not be typed by latex agglutination. All 312 isolates except 5 could be typed by the three PCR methods combined. Two of these methods were multiplex assays. Among the isolates that were typeable by both latex agglutinatio...

  7. A CORRELATION STUDY OF TOTAL SALIVARY COUNTS AND VIRULENT MARKERS OF STREPTOCOCCUS MUTANS WITH CARIES EXPERIENCE

    OpenAIRE

    Gandhimathi C; . Michael A.

    2014-01-01

    The aim of the study was to evaluate an impending relationship between salivary Streptococcus mutans count, sucrose dependent glass adherence, and water insoluble glucan synthesis of isolated strains of Streptococcus mutans with caries experience among young adults between the age group of 20 to 23 years which may enable future planning of caries prevention in adults. A total of 70 dental students undergoing compulsory rotary internship were selected for the study based on...

  8. Effect of Xylitol on Growth of Streptococcus pneumoniae in the Presence of Fructose and Sorbitol

    OpenAIRE

    Tapiainen, Terhi; Kontiokari, Tero; Sammalkivi, Laura; Ikäheimo, Irma; Koskela, Markku; Uhari, Matti

    2001-01-01

    Xylitol is effective in preventing acute otitis media by inhibiting the growth of Streptococcus pneumoniae. To clarify this inhibition we used fructose, which is known to block similar growth inhibition observed in Streptococcus mutans. In addition, we evaluated the efficacy of sorbitol in inhibiting the growth of pneumococci, as sorbitol is widely used for indications similar to those for which xylitol is used. The addition of 5% xylitol to the growth medium resulted in marked growth inhibit...

  9. ANTIBACTERIAL EFFICACY OF VARIETY PLANTS AGAINST THE RESISTANT STREPTOCOCCUS WHICH CAUSE CLINICAL MASTITIS IN COWS

    OpenAIRE

    SHAZA ANWAR AL LAHAM; FRDOOS MOHAMMAD AL FADEL

    2013-01-01

    Streptococcus is considered to be one of the most dangerous causes of Clinical mastitis in cows. The aim of this study was to investigate the effectiveness of extracts prepared from different parts of the flowing plants: Oleaeuropea Linn(Oleaceae), Myrtuscommunis Linn (Liliaceae) ,thymus vulgaris Linn (Laminaceae), Rosemery Linn(Laminaceae), Ficuscarica Linn (Moraceae), and Achilleafalcata Linn(Asteraceae) against resistant Streptococcus in 1371 Samples of milk. This work was achieved in four...

  10. Acquisition of Host Plasmin Activity by the Swine Pathogen Streptococcus suis Serotype 2

    OpenAIRE

    Jobin, Marie-Claude; Brassard, Julie; Quessy, Sylvain; Gottschalk, Marcelo; Grenier, Daniel

    2004-01-01

    In this study, the plasminogen-binding activity of Streptococcus suis serotype 2 was investigated. Bound human plasminogen was activated by purified streptokinase, urokinase, or Streptococcus dysgalactiae subsp. equisimilis culture supernatant. Both human and porcine plasminogen were bound by S. suis. Binding was inhibited by ?-aminocaproic acid, and the plasminogen receptor was heat and sodium dodecyl sulfate resistant. One of the receptors was identified as glyceraldehyde-3-phosphate dehydr...

  11. A Novel Gene Involved in the Survival of Streptococcus mutans under Stress Conditions

    OpenAIRE

    Li, Dan; Shibata, Yukie; Takeshita, Toru; Yamashita, Yoshihisa

    2014-01-01

    A Streptococcus mutans mutant defective in aciduricity was constructed by random-insertion mutagenesis. Sequence analysis of the mutant revealed a mutation in gidA, which is known to be involved in tRNA modification in Streptococcus pyogenes. Complementation of gidA by S. pyogenes gidA recovered the acid tolerance of S. mutans. Although the gidA-inactivated S. pyogenes mutant exhibited significantly reduced expression of multiple extracellular virulence proteins, the S. mutans mutant did n...

  12. Comparison of experimental models for Streptococcus suis infection of conventional pigs

    OpenAIRE

    Pallarés, Francisco J.; Halbur, Patrick G.; Schmitt, Cameron S.; Roth, James A.; Opriessnig, Tanja; Thomas, Peter J; Kinyon, Joann M.; Murphy, Dee; Frank, Dagmar E.; Hoffman, Lorraine J.

    2003-01-01

    Four different experimental models for Streptococcus suis-induced disease were compared to find a model that closely mimics naturally occurring disease in conventional pigs. Fourteen, 2-week old pigs free of S. suis type 2 were used in 2 experiments. In experiment 1, 3 pigs were inoculated intravenously (IV) and 3 pigs intranasally (IN) with S. suis. Two out of 3 of the IV-inoculated pigs exhibited signs of severe central nervous system disease (CNS) and were euthanized. Streptococcus suis ty...

  13. Streptococcus gallolyticus subsp. pasteurianus en líquido cefalorraquídeo de un paciente pediátrico / Streptococcus gallolyticus subsp. pasteurianus isolated from cerebrospinal fluid in a pediatric patient

    Scientific Electronic Library Online (English)

    Liz M, Vélez Balestro; María R., Baroni; Maria C., Ochoteco; María L., Zurbriggen; Stella M., Virgolini.

    2013-12-01

    Full Text Available Hasta la fecha se han descrito casos de meningitis por Streptococcus gallolyticus subsp. pasteurianus en adultos, y de los pocos casos pediátricos, el mayor número se presentó en neonatos. En este trabajo presentamos un caso de meningitis y bacteriemia por este estreptococo en un paciente de 9 meses [...] , con reiteradas hospitalizaciones por enfermedades respiratorias; este constituye el primer aislamiento documentado del citado microorganismo en Santa Fe. Abstract in english Streptococcus gallolyticus subsp. pasteurianus is known to cause bacterial meningitis in adults, and most of the few pediatric cases observed occurred in neonates. We report the case of a 9-month old boy with a history of repeated hospitalizations due to respiratory diseases, who presented meningiti [...] s and bacteremia by Streptococcus gallolyticus subsp. pasterianus. To our knowledge, this is the first reported case in Santa Fe to this date.

  14. Group B streptococcus colonization of Romanian women: phenotypic traits of isolates from vaginal swabs.

    Science.gov (United States)

    Usein, Codru?a-Romani?a; Petrini, Anca; Georgescu, Raluca; Grigore, Laura; Str?u?, Monica; Ungureanu, Vasilica

    2009-01-01

    In the attempt to enrich the local contemporary laboratory data regarding the group B streptococcus (GBS) colonization, isolates obtained from the vaginal swab cultures were characterized for their serotype distribution and antibiotic susceptibility. The 100 GBS isolates analyzed were collected during a four-month period of year 2009 from women screened in ambulatory for vaginal carriage of GBS. The GBS isolates were classified based on their capsular polysaccharide structures using commercially available antisera. Susceptibility to penicillin, ampicillin, erithromycin, clindamycin, tetracycline, ofloxacin, and chloramphenicol was initially tested using antibiotic disk diffusion technique according to CLSI guidelines. Minimum inhibitory concentrations of erythromycin and tetracycline for the isolates with reduced susceptibility were evaluated according to the CLSI criteria and macrolide-lincosamide-streptogramin B (MLSB) resistance was investigated by a double-disk test with erythromycin and clindamycin disks. All the GBS isolates were serotypeable. Their distribution comprised six different serotypes of which serotypes II (26%), III (26%), and Ia (19%) prevailed and no serotype VI, VII, and VIII isolates were found. Overall, the GBS isolates were fully susceptible to penicillin and ampicillin, but the rates of susceptibility to the other antimicrobial agents tested were decreased, ranging from 87% for chloramphenicol to 5% for tetracycline. Reduced susceptibility to clindamycin and erythromycin was detected in 18% and 19% of isolates, respectively. For the latter, 84% displayed a constitutive MLSB phenotype, 11% had an inducible MLSB phenotype, and M phenotype was expressed by 5% of them. Erythromycin-resistant GBS isolates displayed concurrently resistance to at least one more antibiotic. In conclusion, according to our study the most frequent GBS serotypes isolated from the vaginal microflora were II and III, followed by serotype Ia. While the GBS isolates remain susceptible to beta-lactams, resistance to alternative antimicrobial drugs such as erythromycin and clindamycin seems to be an increasing concern for our region. Further phenotypic and genotypic studies are required to identify specific aspects of GBS strains colonizing or infecting the local population. PMID:20583478

  15. Translation quality control is maintained by the penicillin resistance factor MurM in Streptococcus pneumoniae

    DEFF Research Database (Denmark)

    Shepherd, Jennifer; Ibba, Michael

    2013-01-01

    Streptococcus pneumoniae is a causative agent of nosocomial infections such as pneumonia, meningitis and septicaemia. Penicillin resistance in S. pneumoniae depends in part upon MurM, an aminoacyl-tRNA-ligase that attaches L-serine or L-alanine to the stem peptide lysine of Lipid II in cell wall peptidoglycan. To investigate the exact substrates the translation machinery provides MurM, quality control by alanyl-tRNA synthetase (AlaRS) was investigated. AlaRS mischarged serine and glycine to tRNAAla, as observed in other bacteria, and also transferred alanine, serine and glycine to tRNAPhe. S. pneumoniae tRNAPhe has an unusual U4:C69 mismatch in its acceptor stem that prevents editing by phenylalanyl-tRNA synthetase (PheRS), leading to the accumulation of misaminoacylated tRNAs that could serve as substrates for translation or for MurM. Whilst the peptidoglycan layer of S. pneumoniae tolerates a combination of both branched and linear muropeptides, deletion of MurM results in a reversion to penicillin sensitivity in strains that were previously resistant. However, since MurM is not required for cell viability, the reason for its functional conservation across all strains of S. pneumoniae has remained elusive. We now show that MurM is directly involved in translation quality control by acting as a broad specificity trans editing factor that specifically deacylates tRNA misaminoacylated with either serine or alanine. This activity of MurM does not require the presence of its second substrate, Lipid II, and can functionally substitute for the activity of widely conserved editing domain homologues of AlaRS, termed AlaXPs proteins, which are themselves absent from S. pneumoniae.

  16. Involvement of the detoxifying enzyme lactoylglutathione lyase in Streptococcus mutans aciduricity.

    Science.gov (United States)

    Korithoski, Bryan; Lévesque, Céline M; Cvitkovitch, Dennis G

    2007-11-01

    Streptococcus mutans, a normal inhabitant of dental plaque, is considered a primary etiological agent of dental caries. Its main virulence factors are acidogenicity and aciduricity, the abilities to produce acid and to survive and grow at low pH, respectively. Metabolic processes are finely regulated following acid exposure in S. mutans. Proteome analysis of S. mutans demonstrated that lactoylglutathione lyase (LGL) was up-regulated during acid challenge. The LGL enzyme catalyzes the conversion of toxic methylglyoxal, derived from glycolysis, to S-D-lactoylglutathione. Methylglyoxal inhibits the growth of cells in all types of organisms. The current study aimed to investigate the relationship between LGL and aciduricity and acidogenicity in S. mutans. An S. mutans isogenic mutant defective in lgl (LGLKO) was created, and its growth kinetics were characterized. Insertional inactivation of lgl resulted in an acid-sensitive phenotype. However, the glycolytic rate at pH 5.0 was greater for LGLKO than for S. mutans UA159 wild-type cells. LGL was involved in the detoxification of methylglyoxal, illustrated by the absence of enzyme activity in LGLKO and the hypersensitivity of LGLKO to methylglyoxal, compared with UA159 (MIC of 3.9 and 15.6 mM, respectively). Transcriptional analysis of lgl conducted by quantitative real-time PCR revealed that lgl was up-regulated (approximately sevenfold) during the exponential growth phase compared with that in the stationary growth phase. Gene expression studies conducted at low pH demonstrated that lgl was induced during acidic growth (approximately 3.5-fold) and following acid adaptation (approximately 2-fold). This study demonstrates that in S. mutans, LGL functions in the detoxification of methylglyoxal, resulting in increased aciduricity. PMID:17720789

  17. Understanding Streptococcus suis serotype 2 infection in pigs through a transcriptional approach

    Directory of Open Access Journals (Sweden)

    Long Tiansi

    2011-05-01

    Full Text Available Abstract Background Streptococcus suis serotype 2 (S. suis 2 is an important pathogen of pigs. S suis 2 infections have high mortality rates and are characterized by meningitis, septicemia and pneumonia. S. suis 2 is also an emerging zoonotic agent and can infect humans that are exposed to pigs or their by-products. To increase our knowledge of the pathogenesis of meningitis, septicemia and pneumonia in pigs caused by S. suis 2, we profiled the response of peripheral blood mononuclear cells (PBMC, brain and lung tissues to infection with S. suis 2 strain SC19 using the Affymetrix Porcine Genome Array. Results A total of 3,002 differentially expressed transcripts were identified in the three tissues, including 417 unique genes in brain, 210 in lung and 213 in PBMC. These genes showed differential expression (DE patterns on analysis by visualization and integrated discovery (DAVID. The DE genes involved in the immune response included genes related to the inflammatory response (CD163, the innate immune response (TLR2, TLR4, MYD88, TIRAP, cell adhesion (CD34, SELE, SELL, SELP, ICAM-1, ICAM-2, VCAM-1, antigen processing and presentation (MHC protein complex and angiogenesis (VEGF, together with genes encoding cytokines (interleukins. Five selected genes were validated by qRT-PCR analysis. Conclusions We studied the response to infection with S. suis 2 strain SC19 by microarray analysis. Our findings confirmed some genes identified in previous studies and discovered numerous additional genes that potentially function in S. suis 2 infections in vivo. This new information will form the foundation of future investigations into the pathogenesis of S. suis.

  18. Genotypic characterization of initial acquisition of Streptococcus mutans in American Indian children

    Directory of Open Access Journals (Sweden)

    David J. Lynch

    2015-04-01

    Full Text Available Background: Severe-early childhood caries (S-ECC is one of the most common infectious diseases in children and is prevalent in lower socio-economic populations. American Indian children suffer from the highest levels of S-ECC in the United States. Members of the mutans streptococci, Streptococcus mutans, in particular, are key etiologic agents in the development of caries. Children typically acquire S. mutans from their mothers and early acquisition is often associated with higher levels of tooth decay. Methods: We have conducted a 5-year birth cohort study with a Northern Plains Tribe to determine the temporality and fidelity of S. mutans transmission from mother to child in addition to the genotypic diversity of S. mutans in this community. Plaque samples were collected from 239 mother/child dyads at regular intervals from birth to 36 months and S. mutans were isolated and genotyped by arbitrarily primed-polymerase chain reaction (AP-PCR. Results: Here we present preliminary findings from a subset of the cohort. The focus for this paper is on initial acquisition events in the children. We identified 17 unique genotypes in 711 S. mutans isolates in our subset of 40 children, 40 mothers and 14 primary caregivers. Twelve of these genotypes were identified in more than one individual. S. mutans colonization occurred by 16 months in 57.5% of the children and early colonization was associated with higher decayed, missing and filled surface (DMFS scores (p=0.0007. Children colonized by S. mutans shared a common genotype with their mothers 47.8% of the time. While multiple genotypes were common in adults, only 10% of children harbored multiple genotypes. Conclusion: These children acquire S. mutans at an earlier age than the originally described ‘window of infectivity’ and often, but not exclusively, from their mothers. Early acquisition is associated with both the caries status of the children and the mothers.

  19. Pluronics-Formulated Farnesol Promotes Efficient Killing and Demonstrates Novel Interactions with Streptococcus mutans Biofilms

    Science.gov (United States)

    Mogen, Austin B.; Chen, Fu; Ahn, Sang-Joon; Burne, Robert A.; Wang, Dong; Rice, Kelly C.

    2015-01-01

    Streptococcus mutans is the primary causative agent of dental caries, one of the most prevalent diseases in the United States. Previously published studies have shown that Pluronic-based tooth-binding micelles carrying hydrophobic antimicrobials are extremely effective at inhibiting S. mutans biofilm growth on hydroxyapatite (HA). Interestingly, these studies also demonstrated that non-binding micelles (NBM) carrying antimicrobial also had an inhibitory effect, leading to the hypothesis that the Pluronic micelles themselves may interact with the biofilm. To explore this potential interaction, three different S. mutans strains were each grown as biofilm in tissue culture plates, either untreated or supplemented with NBM alone (P85), NBM containing farnesol (P85F), or farnesol alone (F). In each tested S. mutans strain, biomass was significantly decreased (SNK test, p mutans biofilms grown with NBM containing triclosan. Parallel CFU/ml determinations revealed that biofilm growth in the presence of P85F resulted in a 3-log reduction in viability, whereas F decreased viability by less than 1-log. Wild-type biofilms grown in the absence of sucrose or gtfBC mutant biofilms grown in the presence of sucrose did not form towers. However, increased cell killing with P85F was still observed, suggesting that cell killing is independent of tower formation. Finally, repeated treatment of pre-formed biofilms with P85F was able to elicit a 2-log reduction in viability, whereas parallel treatment with F alone only reduced viability by 0.5-log. Collectively, these results suggest that Pluronics-formulated farnesol induces alterations in biofilm architecture, presumably via interaction with the sucrose-dependent biofilm matrix, and may be a viable treatment option in the prevention and treatment of pathogenic plaque biofilms. PMID:26222384

  20. Mechanism of killing of streptococcus mutans by light-activated drugs

    Science.gov (United States)

    Burns, Tracy; Wilson, Michael; Pearson, G. J.

    1996-01-01

    Recent studies have shown that cariogenic bacteria can be killed when exposed to low power laser light in the presence of a photosensitizing agent. The purpose of this study was to determine the mechanism by which the cariogenic bacterium Streptococcus mutans can be killed by toluidine blue O and helium neon laser light. To determine whether membrane damage occurred, suspensions of sensitized S. mutans were exposed to a 7.3 mW HeNe laser for 30 mins and samples removed every 5 mins. Survivors were enumerated by viable counting on tryptone soya agar plates and cell free filtrates were assayed for phosphate and (beta) -galactosidase. Lipid peroxidation was assessed by assaying for malondialdehyde, a by- product of lipid peroxidation. The role of oxygen and reactive oxygen species was studied by exposing sensitized bacteria to laser light (1) under different atmospheric conditions, (2) in the presence of deuterium oxide, and (3) in the presence of inhibitors of reactive oxygen species. Following exposure of sensitizede S. mutans to 13.2 J of HeNe laser light, 2.6 nmoles of phosphate and 228 nmoles of (beta) -galactosidase were detected in the cell free filtrates. Ten micrometers oles of malondialdehyde were also detected. When the sensitized bacteria were exposed to laser light under anaerobic conditions there was no significant decrease in the viable count compared to a 60% kill in the presence of oxygen. In the presence of D2O there was a 15-fold increase in the numbers of bacteria killed. O.1 M methionine and 0.5 M sodium azide each afforded 98% protection from lethal photosensitization. These results imply that lethal photosensitization results from membrane damage due to lipid peroxidation and that reactive oxygen species are mediators of this process.

  1. Carriage rate and serotypes of Streptococcus pneumoniae amongst children in Thika Hospital, Kenya

    Directory of Open Access Journals (Sweden)

    Susan Githii

    2013-03-01

    Full Text Available Streptococcus pneumoniae is a major cause of morbidity and mortality worldwide. Rates of carriage are highest in infants and the elderly. The objectives of this study were to determine the rate of nasopharyngeal colonization by S. pneumoniae, and to describe the antibiotic resistant patterns and the serotypes of the carried isolates. A cross-sectional study design was used. Nasopharyngeal swabs were collected from 315 children in the months of Octoberand November 2010 and processed to isolate S. pneumoniae. The isolates were serotyped by the Quellung reaction and their antibiotic susceptibilities assessed by the disc diffusion method. The overall nasopharyngeal carriage rate for S. pneumoniae was 17%. Seventeen serotypes were detected amongst 55 strains analysed: 6A, 23F, 19F, 13, 6B, 14A, 20, 7C, 1,15B, 35B, 19A, 11A, 34, 5, 3 and 23A. Susceptibility testing revealed that nearly all (98% were resistant to cotrimoxazole, 9% were resistant to penicillin and 7% to cefotaxime. Resistance to chloramphenicol and erythromycin was 2% and 4%, respectively. All isolates were fully sensitive to tetracycline. High levels of cotrimoxazole resistance and some resistance to other antimicrobial agents commonly used in Thika District Hospital shows that there is need to revise antimicrobial policy in this region in the treatment of invasive pneumococcal infections. The frequent serotypes found in this study have previously been associated with pneumococcal infectionsin children. Several of these serotypes are included in the ten-valent vaccine and therefore useof this vaccine will help reduce pneumococcal infections in Thika.

  2. Characterization of the functional domains of the SloR metalloregulatory protein in Streptococcus mutans.

    Science.gov (United States)

    Haswell, Jeffrey R; Pruitt, Benjamin W; Cornacchione, Louis P; Coe, Christopher L; Smith, Evan G; Spatafora, Grace A

    2013-01-01

    Streptococcus mutans is a commensal member of the healthy plaque biofilm and the primary causative agent of dental caries. The present study is an investigation of SloR, a 25-kDa metalloregulatory protein that modulates genes responsible for S. mutans-induced cariogenesis. Previous studies of SloR homologues in other bacterial pathogens have identified three domains critical to repressor functionality: an N-terminal DNA-binding domain, a central dimerization domain, and a C-terminal FeoA (previously SH3-like) domain. We used site-directed mutagenesis to identify critical amino acid residues within each of these domains of the SloR protein. Select residues were targeted for mutagenesis, and nonconservative amino acid substitutions were introduced by overlap extension PCR. Furthermore, three C-terminally truncated SloR variants were generated using conventional PCR. The repressor functionality and DNA-binding ability of each variant was assessed using CAT reporter gene assays, real-time semiquantitative reverse transcriptase (qRT)-PCR, and electrophoretic mobility shift assays. We identified 12 residues within SloR that cause significant derepression of sloABC promoter activity (P < 0.05) compared to the results for wild-type SloR. Derepression was particularly noteworthy in metal ion-binding site 1 mutants, consistent with the site's importance in gene repression by SloR. In addition, a hyperactive SloR(E169A/Q170A) mutant was identified as having significantly heightened repression of sloABC promoter activity, and experiments with C-terminal deletion mutants support involvement of the FeoA domain in SloR-mediated gene repression. Given these results, we describe the functional domains of the S. mutans SloR protein and propose that the hyperactive mutant could serve as a target for rational drug design aimed at repressing SloR-mediated virulence gene expression. PMID:23104811

  3. Complete genome and comparative analysis of Streptococcus gallolyticus subsp. gallolyticus, an emerging pathogen of infective endocarditis

    Directory of Open Access Journals (Sweden)

    Dreier Jens

    2011-08-01

    Full Text Available Abstract Background Streptococcus gallolyticus subsp. gallolyticus is an important causative agent of infectious endocarditis, while the pathogenicity of this species is widely unclear. To gain insight into the pathomechanisms and the underlying genetic elements for lateral gene transfer, we sequenced the entire genome of this pathogen. Results We sequenced the whole genome of S. gallolyticus subsp. gallolyticus strain ATCC BAA-2069, consisting of a 2,356,444 bp circular DNA molecule with a G+C-content of 37.65% and a novel 20,765 bp plasmid designated as pSGG1. Bioinformatic analysis predicted 2,309 ORFs and the presence of 80 tRNAs and 21 rRNAs in the chromosome. Furthermore, 21 ORFs were detected on the plasmid pSGG1, including tetracycline resistance genes telL and tet(O/W/32/O. Screening of 41 S. gallolyticus subsp. gallolyticus isolates revealed one plasmid (pSGG2 homologous to pSGG1. We further predicted 21 surface proteins containing the cell wall-sorting motif LPxTG, which were shown to play a functional role in the adhesion of bacteria to host cells. In addition, we performed a whole genome comparison to the recently sequenced S. gallolyticus subsp. gallolyticus strain UCN34, revealing significant differences. Conclusions The analysis of the whole genome sequence of S. gallolyticus subsp. gallolyticus promotes understanding of genetic factors concerning the pathogenesis and adhesion to ECM of this pathogen. For the first time we detected the presence of the mobilizable pSGG1 plasmid, which may play a functional role in lateral gene transfer and promote a selective advantage due to a tetracycline resistance.

  4. Analysis of the in vitro adherence of Streptococcus mutans and Candida albicans / Análise da aderência in vitro de Streptococcus mutans e Candida albicans

    Scientific Electronic Library Online (English)

    Dicler de Sant' Anna Vitor, Barbieri; Vânia Aparecida, Vicente; Fabian Calixto, Fraiz; Osmir José, Lavoranti; Terezinha Inês Estivalet, Svidzinski; Rosângela Lameira, Pinheiro.

    2007-12-01

    Full Text Available O objetivo deste trabalho foi investigar a capacidade de aderência in vitro de Streptococcus mutans e Candida albicans. Ensaios de aderência foram realizados in vitro na superfície dentária, com posterior análise por Microscopia Eletrônica de Varredura (M.E.V.). Dentes humanos extraídos foram inocul [...] ados com Streptococcus mutans e Candida albicans, além de ambas espécies em conjunto, e foram incubados a 37ºC por 21 dias. Os inóculos eram provenientes de amostras salivares de crianças colonizadas por ambos microrganismos. Como controles foram utilizadas linhagens de referência ATCC dos dois microrganismos. A análise por M.E.V. mostrou a formação de um biofilme que cobriu toda a superfície dentária analisada de forma mais homogênea quando incubados juntos do que separadamente. Um segundo experimento foi desenvolvido utilizando isolados mostrando maior aderência dos experimentos anteriores e cortes de polietileno de alta densidade como substrato. A potencialização da capacidade de aderência de Streptococcus mutans e Candida albicans em associação foi confirmada. Abstract in english The objective of the present study was to investigate the in vitro adherence capacity of Streptococcus mutans and Candida albicans. Adherence assays were conducted on dental surfaces and analyzed by scanning electron microscopy (SEM). Extracted human teeth were inoculated with Streptococcus mutans o [...] r Candida albicans and with both species simultaneously, and incubated at 37ºC for 21 days. Bacterial inocula had been obtained from saliva samples of children that had been colonized by both organisms. ATCC reference strains were used as controls. SEM analyses showed that the biofilm that covered the entire analyzed dental surface was more homogeneous inoculated with the two microorganisms simultaneously than with each species separately. In a second experiment, carried out with isolates that had shown the highest adherence the isolates were tested for adherence to high-density polyethylene substrates. The potentialization of the adherence capacity of Streptococcus mutans and Candida albicans when in association was confirmed.

  5. Analysis of the in vitro adherence of Streptococcus mutans and Candida albicans Análise da aderência in vitro de Streptococcus mutans e Candida albicans

    Directory of Open Access Journals (Sweden)

    Dicler de Sant'Anna Vitor Barbieri

    2007-12-01

    Full Text Available The objective of the present study was to investigate the in vitro adherence capacity of Streptococcus mutans and Candida albicans. Adherence assays were conducted on dental surfaces and analyzed by scanning electron microscopy (SEM. Extracted human teeth were inoculated with Streptococcus mutans or Candida albicans and with both species simultaneously, and incubated at 37ºC for 21 days. Bacterial inocula had been obtained from saliva samples of children that had been colonized by both organisms. ATCC reference strains were used as controls. SEM analyses showed that the biofilm that covered the entire analyzed dental surface was more homogeneous inoculated with the two microorganisms simultaneously than with each species separately. In a second experiment, carried out with isolates that had shown the highest adherence the isolates were tested for adherence to high-density polyethylene substrates. The potentialization of the adherence capacity of Streptococcus mutans and Candida albicans when in association was confirmed.O objetivo deste trabalho foi investigar a capacidade de aderência in vitro de Streptococcus mutans e Candida albicans. Ensaios de aderência foram realizados in vitro na superfície dentária, com posterior análise por Microscopia Eletrônica de Varredura (M.E.V.. Dentes humanos extraídos foram inoculados com Streptococcus mutans e Candida albicans, além de ambas espécies em conjunto, e foram incubados a 37ºC por 21 dias. Os inóculos eram provenientes de amostras salivares de crianças colonizadas por ambos microrganismos. Como controles foram utilizadas linhagens de referência ATCC dos dois microrganismos. A análise por M.E.V. mostrou a formação de um biofilme que cobriu toda a superfície dentária analisada de forma mais homogênea quando incubados juntos do que separadamente. Um segundo experimento foi desenvolvido utilizando isolados mostrando maior aderência dos experimentos anteriores e cortes de polietileno de alta densidade como substrato. A potencialização da capacidade de aderência de Streptococcus mutans e Candida albicans em associação foi confirmada.

  6. Production of monoclonal antibodies against Streptococcus mutans antigens Produção de anticorpos monoclonais contra antígenos de Streptococcus mutans

    Directory of Open Access Journals (Sweden)

    Antonio Carlos Victor Canettieri

    2006-12-01

    Full Text Available Several studies have been conducted in the last decades aiming to obtain an anti-caries vaccine, however some studies have demonstrated cross reactivity between Streptococcus mutans surface antigens and the human cardiac tissue. In this work, the reactivity of five anti-Streptococcus mutans monoclonal antibodies (MoAb (24A, 56G, C8, E8 and F6 was tested against oral streptococci, cardiac antigens and skeletal and cardiac myosins, aiming to evaluate the specificity of these MoAb. The hybrid producers of immunoglobulins of the IgG2b class were cloned by limit dilution and expanded in vivo. MoAb were tested by ELISA. The hybrid 24A reacted with S. mutans CCT 1910, S. salivarius CCT 0365 and S. pyogenes T23. No reactivity difference was observed among the tested species. Cross reactivity with heart and cardiac myosin was not confirmed and only reaction with myosin of skeletal muscle was observed (p = 0.0381. The hybrid 56G reacted with all the tested microorganisms and there was statistically significant difference between S. mutans and S. pyogenes T23 (p Diversos estudos foram realizados nas últimas décadas com o intuito de se obter uma vacina anticárie dentária, mas alguns trabalhos têm demonstrado reatividade cruzada entre antígenos de superfície de Streptococcus mutans e tecido cardíaco humano. Neste trabalho, foi testada a reatividade de cinco anticorpos monoclonais (AcMo anti-Streptococcus mutans (24A, 56G, C8, E8 e F6 contra estreptococos orais, antígenos cardíacos e miosinas esquelética e cardíaca, no intuito de avaliar a especificidade desses AcMo. Os híbridos produtores de imunoglobulinas da classe IgG2b foram clonados por diluição limite e expandidos in vivo. Os AcMo foram testados por ELISA. O híbrido 24A reagiu com S. mutans CCT 1910, S. salivarius CCT 0365 e S. pyogenes T23. Nenhuma diferença de reatividade foi detectada entre as espécies analisadas. Reatividade cruzada com coração e miosina cardíaca não foi confirmada, existindo somente reação com miosina de músculo esquelético (p = 0,0381. O híbrido 56G reagiu com todos os microrganismos testados e houve diferença estatisticamente significante entre S. mutans e S. pyogenes T23 (p < 0,001. Este híbrido também reagiu com miosina de músculo esquelético (p = 0,0095. C8, E8 e F6 apresentaram baixa reatividade contra cepas de estreptococos orais e nenhuma reatividade com antígenos cardíacos. Os dados deste trabalho demonstraram que os AcMo 24A e 56G anti-S. mutans reagiram com S. pyogenes e S. salivarius, confirmando a existência de antígenos comuns entre essas espécies. Esses AcMo avaliados apresentaram baixa reatividade cruzada com miosina de músculo esquelético, porém a atividade anticoração não foi confirmada.

  7. Bacteriemia por Streptococcus pyogenes: Presentación de un caso clínico con aparición tardía de neumonía / Pneumonia caused by Streptococcus pyogenes: Report of one case

    Scientific Electronic Library Online (English)

    CAROLINA, RAMÍREZ; JUAN PABLO, ARAB; GONZALO, EYMIN.

    2010-07-01

    Full Text Available [...] Abstract in english We report a 58-year-old female presenting with fever and vomiting. The initial laboratory examination disclosed two blood cultures that were positive for Streptococcus Pyogenes. An abdominal CAT scan showed a right basal pneumonia. The patient was treated with antimicrobials and discharged with oral [...] cefadroxil for 21 days. One month after discharge she was asymptomatic and with a normal C reactive protein. Pneumonia is an important differential diagnosis in unknown origin bacteremia caused by Streptococcus Pyogenes. It may have a fulminant evolution and may complicate with abscess and empyema.

  8. Salivaricin G32, a Homolog of the Prototype Streptococcus pyogenes Nisin-Like Lantibiotic SA-FF22, Produced by the Commensal Species Streptococcus salivarius

    OpenAIRE

    Tagg, John R.; Anna L. Wescombe; Inglis, Megan A.; Burton, Jeremy P.; Jack, Ralph W.; Karen P. Dierksen; Power, Daniel A.; Kristin H. Dyet; Wescombe, Philip A.

    2012-01-01

    Salivaricin G32, a 2667?Da novel member of the SA-FF22 cluster of lantibiotics, has been purified and characterized from Streptococcus salivarius strain G32. The inhibitory peptide differs from the Streptococcus pyogenes—produced SA-FF22 in the absence of lysine in position 2. The salivaricin G32 locus was widely distributed in BLIS-producing S. salivarius, with 6 (23%) of 26 strains PCR-positive for the structural gene, slnA. As for most other lantibiotics produced by S. salivarius, the sali...

  9. Streptococcus mutans and Streptococcus sobrinus detection by Polymerase Chain Reaction and their relation to dental caries in 12 and 15 year-old schoolchildren in Valencia (Spain)

    OpenAIRE

    Sánchez-Acedo, Mateo; Montiel-Company, José M.; Dasí-Fernández, Francisco; Almerich-Silla, José M.

    2013-01-01

    A cross-sectional study was carried out to determine the prevalence of Streptococcus mutans and Streptococcus sobrinus and the association of the two in a random sample (n=614) of the child population of the region of Valencia (Spain). Saliva samples were analyzed by the quantitative polymerase chain reaction (PCR) method to study the relation of these bacteria to caries prevalence and the DMFT index. The prevalence of S. mutans was 35.4% at age 12 and 22.9% at age 15, that of S. sobrinus ...

  10. Bacteriemia por Streptococcus pyogenes: Presentación de un caso clínico con aparición tardía de neumonía Pneumonia caused by Streptococcus pyogenes: Report of one case

    Directory of Open Access Journals (Sweden)

    CAROLINA RAMÍREZ

    2010-07-01

    Full Text Available We report a 58-year-old female presenting with fever and vomiting. The initial laboratory examination disclosed two blood cultures that were positive for Streptococcus Pyogenes. An abdominal CAT scan showed a right basal pneumonia. The patient was treated with antimicrobials and discharged with oral cefadroxil for 21 days. One month after discharge she was asymptomatic and with a normal C reactive protein. Pneumonia is an important differential diagnosis in unknown origin bacteremia caused by Streptococcus Pyogenes. It may have a fulminant evolution and may complicate with abscess and empyema.

  11. Influence of time, toothpaste and saliva in the retention of Streptococcus mutans and Streptococcus sanguinis on different toothbrushes

    Scientific Electronic Library Online (English)

    Julia Caroline, SCHMIDT; Miriam, BUX; Elisabeth, FILIPUZZI-JENNY; Eva Maria, KULIK; Tuomas, WALTIMO; Roland, WEIGER; Clemens, WALTER.

    2014-06-01

    Full Text Available Objectives: The intraoral transmission of cariogenic and periodontopathogenic species seems to be facilitated by contaminated toothbrushes and other oral hygiene devices. The aim of this investigation was to analyze the in vitro retention and survival rate of Streptococcus mutans and Streptococcus [...] sanguinis on different toothbrushes. The impacts of human saliva and antimicrobial toothpaste on these parameters were further evaluated. Material and Methods: Part I: Four toothbrushes (Colgate 360°, Curaprox CS5460 ultra soft, elmex InterX, Trisa Flexible Head3) were contaminated by S. mutans DSM 20523 or S. sanguinis DSM 20068 suspensions for three minutes. Bacteria were removed from the toothbrushes after either three minutes (T0) or 24 hours (T24) of dry storage and grown on Columbia blood agar plates for the quantification of colony-forming units (CFUs). Part II: The effects of saliva from a caries-active or a caries-inactive person and of toothpaste containing 0.12% chlorhexidine digluconate were also tested. Results: Part I: After three minutes of dry storage, approximately one percent of the bacteria were still detectable on the toothbrushes. After 24 hours, S. sanguinis exhibited a more pronounced decrease in viable cell numbers compared with S. mutans but the differences were not significant (Kruskal-Wallis test, p>0.05). Part II: The addition of human saliva from a caries-active or caries-inactive person slightly increased the retention of both streptococcal species at T0. The use of toothpaste had no influence on the amount of viable streptococci at T0, but it reduced the microbial load after 24 hours of storage. There were only slight nonsignificant differences (p>0.05) between the four toothbrushes. Conclusions: In vitro bacterial retention and survival of S. sanguinis and S. mutans on different toothbrushes occurred. Within the limitations of this study, the use of human saliva or an antimicrobial toothpaste did not lead to significant differences in the microbial load on toothbrushes.

  12. Chemical and botanical characterization of Chilean propolis and biological activity on cariogenic bacteria Streptococcus mutans and Streptococcus sobrinus

    Scientific Electronic Library Online (English)

    Leticia, Barrientos; Christian L., Herrera; Gloria, Montenegro; Ximena, Ortega; Jorge, Veloz; Marysol, Alvear; Alejandro, Cuevas; Nicolás, Saavedra; Luis A., Salazar.

    Full Text Available Propolis is a non-toxic natural substance with multiple pharmacological properties including anticancer, antioxidant, fungicidal, antibacterial, antiviral, and anti-inflammatory among others. The aim of this study was to determine the chemical and botanical characterization of Chilean propolis sampl [...] es and to evaluate their biological activity against the cariogenic bacteria Streptococcus mutans and Streptococcus sobrinus. Twenty propolis samples were obtained from beekeeping producers from the central and southern regions of Chile. The botanical profile was determined by palynological analysis. Total phenolic contents were determined using colorimetric assays. Reverse phase HPLC and HPLC-MS were used to determine the chemical composition. The minimum inhibitory concentration (MIC) was determined on S. mutans and S. sobrinus. All propolis samples were dominated by structures from native plant species. The characterization by HPLC/MS, evidenced the presence of quercetin, myricetin, kaempferol, rutine, pinocembrin, coumaric acid, caffeic acid and caffeic acid phenethyl ester, that have already been described in these propolis with conventional HPLC. Although all propolis samples inhibited the mutans streptococci growth, it was observed a wide spectrum of action (MIC 0.90 to 8.22 µgmL-1). Given that results it becomes increasingly evident the need of standardization procedures, where we combine both the determination of botanical and the chemical characterization of the extracts. Research conducted to date, describes a promising effectiveness of propolis in the prevention of caries and other diseases of the oral cavity, making it necessary to develop studies to identify and understand the therapeutic targets or mechanisms of molecular action of the various compounds present on them.

  13. Novel Bacteriophage Lysin with Broad Lytic Activity Protects against Mixed Infection by Streptococcus pyogenes and Methicillin-Resistant Staphylococcus aureus

    OpenAIRE

    Gilmer, Daniel B.; Schmitz, Jonathan E.; Euler, Chad W.; Fischetti, Vincent A

    2013-01-01

    Methicillin-resistant Staphylococcus aureus (MRSA) and Streptococcus pyogenes (group A streptococcus [GrAS]) cause serious and sometimes fatal human diseases. They are among the many Gram-positive pathogens for which resistance to leading antibiotics has emerged. As a result, alternative therapies need to be developed to combat these pathogens. We have identified a novel bacteriophage lysin (PlySs2), derived from a Streptococcus suis phage, with broad lytic activity against MRSA, vancomycin-i...

  14. Using PCR-based detection and genotyping to trace Streptococcus salivarius meningitis outbreak strain to oral flora of radiology physician assistant.

    Science.gov (United States)

    Srinivasan, Velusamy; Gertz, Robert E; Shewmaker, Patricia L; Patrick, Sarah; Chitnis, Amit S; O'Connell, Heather; Benowitz, Isaac; Patel, Priti; Guh, Alice Y; Noble-Wang, Judith; Turabelidze, George; Beall, Bernard

    2012-01-01

    We recently investigated three cases of bacterial meningitis that were reported from a midwestern radiology clinic where facemasks were not worn during spinal injection of contrast agent during myelography procedures. Using pulsed field gel electrophoresis we linked a case strain of S. salivarius to an oral specimen of a radiology physician assistant (RPA). We also used a real-time PCR assay to detect S. salivarius DNA within a culture-negative cerebrospinal fluid (CSF) specimen. Here we extend this investigation through using a nested PCR/sequencing strategy to link the culture-negative CSF specimen to the case strain. We also provide validation of the real-time PCR assay used, demonstrating that it is not solely specific for Streptococcus salivarius, but is also highly sensitive for detection of the closely related oral species Streptococcus vestibularis. Through using multilocus sequence typing and 16S rDNA sequencing we further strengthen the link between the CSF case isolate and the RPA carriage isolate. We also demonstrate that the newly characterized strains from this study are distinct from previously characterized S. salivarius strains associated with carriage and meningitis. PMID:22384169

  15. Radioactively labelled scanning agent

    International Nuclear Information System (INIS)

    According to the invention, a stabilized alcohol solution of a reducing salt preparation has been developed and used for the preparation of radioactively labelled scanning agents, in particular for the liver. These scanning agents contain colloids of sup(99m)Tc and a reduction agent, e.g. SnCl2, TiCl3, CrCl2, FeCl2, etc., and, if necessary, an additional stabilizing agent. Bone scanning agents further contain a phosphate complex and lung scanning agents a macroaggregated albumin. (VJ)

  16. Radiographic scanning agent

    International Nuclear Information System (INIS)

    A composition and method for the preparation of a technetium-99m -based scanning agent are disclosed. The scanning agent is prepared from /sup 99m/Tc, in a +3, +4 and/or +5 oxidation state, and a methanehydroxydiphosphonate bone-seeking agent which carries the radionuclide to bone mineral. The methanehydroxydiphosphonate agent provides scan sharpness equivalent or superior to commercial scanning agents, and is superior for detecting myocardial infarcts, as compared with commercial scanning agents such as ethane-1-hydroxy-1,1-diphosphonate and methanediphosphonate

  17. Chemical warfare agents.

    Science.gov (United States)

    Chauhan, S; Chauhan, S; D'Cruz, R; Faruqi, S; Singh, K K; Varma, S; Singh, M; Karthik, V

    2008-09-01

    Chemical warfare agents (CWA's) are defined as any chemical substance whose toxic properties are utilised to kill, injure or incapacitate an enemy in warfare and associated military operations. Chemical agents have been used in war since times immemorial, but their use reached a peak during World War I. During World War II only the Germans used them in the infamous gas chambers. Since then these have been intermittently used both in war and acts of terrorisms. Many countries have stockpiles of these agents. There has been a legislative effort worldwide to ban the use of CWA's under the chemical weapons convention which came into force in 1997. However the manufacture of these agents cannot be completely prohibited as some of them have potential industrial uses. Moreover despite the remedial measures taken so far and worldwide condemnation, the ease of manufacturing these agents and effectiveness during combat or small scale terrorist operations still make them a powerful weapon to reckon with. These agents are classified according to mechanism of toxicity in humans into blister agents, nerve agents, asphyxiants, choking agents and incapacitating/behavior altering agents. Some of these agents can be as devastating as a nuclear bomb. In addition to immediate injuries caused by chemical agents, some of them are associated with long term morbidities and psychological problems. In this review we will discuss briefly about the historical background, properties, manufacture techniques and industrial uses, mechanism of toxicity, clinical features of exposure and pharmacological management of casualties caused by chemical agents. PMID:21783898

  18. Incremento de la resistencia a eritromicina de Streptococcus pneumoniae, Colombia, 1994-2008 / Increase in erythromycin-resistant Streptococcus pneumoniae in Colombia, 1994-2008

    Scientific Electronic Library Online (English)

    Marylin, Hidalgo; Claudia, Santos; Carolina, Duarte; Elizabeth, Castañeda; Clara Inés, Agudelo.

    2011-03-01

    Full Text Available Introducción. Streptococcus pneumoniae es un agente comúnmente implicado en enfermedad invasora. Los macrólidos constituyen un tratamiento alternativo para las infecciones por S. pneumoniae resistente a los b-lactámicos. Sin embargo, la resistencia a macrólidos se ha incrementado a nivel mundial. Ob [...] jetivo. Determinar la frecuencia de la resistencia a la eritromicina de S. pneumoniae en 15 años de vigilancia y caracterizar fenotípica y genotípicamente los aislamientos resistentes. Materiales y métodos. Se analizaron los datos demográficos de los pacientes, la sensibilidad antimicrobiana y los serotipos de los aislamientos resistentes a la eritromicina, recuperados entre 1994 y 2008. Se determinaron los fenotipos por la técnica del doble disco, y los genotipos, por PCR y PFGE. Todos los aislamientos se recuperaron de enfermedad invasiva y fueron proporcionados por los laboratorios nacionales de salud pública. Resultados. Se recuperaron 3.241 aislamientos invasores; 136 (4,2 %) presentaron resistencia a la eritromicina. La resistencia a la eritromicina se incrementó entre 1994-1996 y 2006-2008, de 2,4 % a 6,9 % en menores de 6 años y, de 3,3 % a 5,7 %, en adultos. Los serotipos más frecuentes fueron 6B (36,8 %), 14 (16,9 %) y 6A (17,6 %). El fenotipo constitutivo cMLSB se determinó en 87 aislamientos; 82 tenían el gen ermB. Elfenotipo M se determinó en 46; 45 tenían el gen mefA, tres aislamientos expresaron fenotipo inducible (iMLSB) y un aislamiento presentaba el gen ermB. Por PFGE, se determinó que 50 aislamientos estaban relacionados con clones internacionales, de los cuales, 58 % eran España6B ST90, 26 % eran España9V ST156, 8 % eran Colombia23F-ST338 y 8 % eran España23F-ST81. Conclusiones. Se observó incremento en la resistencia a la eritromicina, relacionada principalmente con el mecanismo de metilación ribosómica y con el clon España6B-ST90 que ha circulado en Colombia desde 1994. Abstract in english Introduction. Streptococcus pneumoniae is a commonly implicated agent in invasive disease. For infections of S. pneumoniae resistant to b-lactam, macrolides are an alternative treatment. However, resistance to macrolides has increased worldwide as well. Objective. The frequency of resistance to eryt [...] hromycin was determined for S. pneumoniae over a 15-year surveillance period, and the resistant isolates were characterized phenotypically and genotypically. Materials and methods. Demographic data of the patients, antimicrobial susceptibility and serotypes were analyzed for 3,241 S. pneumoniae isolates recovered between 1994 and 2008. The phenotypes were determined by the double-disc technique and genotypes by PCR (polymerase chain reaction) and PFGE (pulsed field gel electrophoresis). Isolates were recovered from invasive diseases and were provided by national public health laboratories. Results. Of the 3,241 isolates, 136 were resistant to erythromycin. In the 12-year period between 1994-1996 and 2006-2008, resistance in each 2-year sampling had increased from 2.4% to 6.9% in children under 6 years and from 3.3% to 5.7% in adults. The most common serotypes were 6B (36.8%), 14 (16.9%) and 6A (17.6%). Constitutive phenotype cMLSB was determined in 87 isolates; 82 of these expressed the ermB gene. Phenotype M was determined in 46 isolates; 45 had the mefA gene. An additional three isolates expressed the inducible phenotype (iMLSB), and one expressed the ermB gene. By PFGE, 50 of the isolates were found to be related to international clones--58% were Spain6B-ST90, 26% Spain9V-ST156, 8% Colombia23F-ST338 and 8% Spain23F-ST81. Conclusion. The increase in erythromycin resistance was primarily related to the mechanism of ribosomal methylation. More than half the cases were congeneric with the clone Spain6B-ST90 that has been circulating in Colombia since 1994.

  19. In Vitro Effect of photodynamic therapy on Aggregatibacter actinomycetemcomitans and Streptococcus sanguinis

    Scientific Electronic Library Online (English)

    Fabiano Dalla Lana, Mattiello; Alan Augusto Kalife, Coelho; Odair Pimentel, Martins; Rodrigo Dalla Lana, Mattiello; José Peixoto, Ferrão Júnior.

    Full Text Available Novos tratamentos são propostos para evitar a progressão da periodontite, sendo a terapia fotodinâmica (PDT) uma notória promessa. Sua aplicação associa o Azul de orto-toluidina a 0,01% (TBO) e uma fonte luminosa a laser de diodo (TwinFlex, Mmoptics), liberando assim, toxinas às bactérias. O objetiv [...] o do estudo é avaliar in vitro a eficiência da PDT sobre Aggregatibacter actinomycetemcomitans (A.a.) e Streptococcus sanguinis (S.s.). Preparou-se suspensões distintas de 2 mL contendo A.a. e S.s. na concentração de 1,5x108 UFC/mL, e divisão de cada suspensão em 3 grupos: Controle (sem tratamento); Corante (suspensão e TBO por 5min) e Corante/Laser (suspensão, TBO por 5 min e laser por 3 min). Promoveu-se a diluição, a semeadura em 20 mL de TSA (A.a.) e de Ágar Brucella (S.s.), em placas de Petri (Método Pourplate), e a incubação da A.a. em microaerofilia e da S.s. em aerobiose, por 48 h a 35oC, para posterior contagem visual das UFC. Os grupos Controle mostraram ótimo crescimento bacteriano (1,5 x 108 UFC/mL). Os grupos Corante não apresentaram redução significativa para ambas bactérias. Os grupos Laser apresentaram redução em relação ao controle, 61,53% para A.a. e 84,32% para S.s. A análise estatística (ANOVA, p Abstract in english New periodontal disease treatments are needed to prevent infection progression. Photodynamic therapy (PDT) is one of the greatest pledges for this purpose. It involves the use of light of specific wavelength to activate a nontoxic photosensitizing agent in the presence of oxygen for eradication of t [...] arget cells, and can be used for photokilling of microorganisms. This study evaluated in vitro the photodynamic effect of 0.01% toluidine blue-O (TBO) in combination with an AlGaInP diode laser light source on Aggregatibacter actinomycetemcomitans (A.a.) and Streptococcus sanguinis (S.s.). Suspensions (2 mL) containing A.a. and S.s. at 1.5 x 108 CFU/mL concentration were prepared and divided into 3 groups: Control group (no treatment), Dye group (inoculum and TBO for 5 min) and Dye/Laser group (inoculum, TBO for 5 min and laser for 3 min). Next, a dilution for subsequent subculture in 20 mL of Trypic Soy Agar (A.a) and Brucella Agar (S.s.) in Petri dishes (Pourplate Method) was done. Incubation of A.a. in microaerophilia and S.s. in aerobiosis at 35oC for 48 h was performed for subsequent visual counting of CFU/mL. Data were analyzed by one-way ANOVA and Tukey’s HSD test at 5% significance level. For both strains, the control group showed a significantly higher (p0.05) in the CFU counts. The Dye/Laser group presented a significant decrease in the CFU counts (p

  20. Biofilm formation, hemolysin production and antimicrobial susceptibilities of Streptococcus agalactiae isolated from the mastitis milk of dairy cows in Shahrekord district, Iran

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    Azizollah Ebrahimi

    2014-12-01

    Full Text Available Streptococcus agalactiae is a major contagious pathogen causing bovine sub-clinical mastitis. The present investigation was carried out to determine some phenotypic characteristics of the S. agalactiae strains isolated from bovine mastitis cases in dairy cows of Shahrekord in the west-center of Iran. One hundred eighty California mastitis test (CMT positive milk samples were bacteriologically studied. A total of 31 (17.2% S. agalactiae isolated. Twenty eight (90.3% of the isolates were biofilm producers. This finding may indicate the high potential of pathogenicity in isolated strains. Sixteen (51.6% isolates were ? hemolysin producers. Only 19.3%, 22.5% and 29.0% of the isolates were sensitive to streptomycin, flumequine and kanamycin, respectively. None of these three agents is recommended for treatment of mastitis cases.

  1. Biofilm formation, hemolysin production and antimicrobial susceptibilities of Streptococcus agalactiae isolated from the mastitis milk of dairy cows in Shahrekord district, Iran.

    Science.gov (United States)

    Ebrahimi, Azizollah; Moatamedi, Azar; Lotfalian, Sharareh; Mirshokraei, Pejhman

    2013-01-01

    Streptococcus agalactiae is a major contagious pathogen causing bovine sub-clinical mastitis. The present investigation was carried out to determine some phenotypic characteristics of the S. agalactiae strains isolated from bovine mastitis cases in dairy cows of Shahrekord in the west-center of Iran. One hundred eighty California mastitis test (CMT) positive milk samples were bacteriologically studied. A total of 31 (17.2%) S. agalactiae isolated. Twenty eight (90.3%) of the isolates were biofilm producers. This finding may indicate the high potential of pathogenicity in isolated strains. Sixteen (51.6%) isolates were ? hemolysin producers. Only 19.3%, 22.5% and 29.0% of the isolates were sensitive to streptomycin, flumequine and kanamycin, respectively. None of these three agents is recommended for treatment of mastitis cases. PMID:25568683

  2. Group B streptococcal neonatal infections in Rio Grande do Sul, Brazil Infecção neonatal por Streptococcus do grupo B no Rio Grande do Sul, Brasil

    OpenAIRE

    MIURA Ernani; Maria Cristina MARTIN

    2001-01-01

    Group B Streptococcus is the most common pathogen found in neonatal sepsis in North America. OBJECTIVES: We describe 15 cases of neonatal infections by Group B Streptococcus (Streptococcus agalactiae) at a Neonatal Intensive Care Unit of a public and teaching hospital. METHODS: We conducted a study at Hospital de Clínicas de Porto Alegre, from January 1st, 1996 to June 30, 1999. Diagnosis of neonatal infection was established according to the findings of Group B Streptococcus in blood culture...

  3. Virulence Gene Pool Detected in Bovine Group C Streptococcus dysgalactiae subsp. dysgalactiae Isolates by Use of a Group A S. pyogenes Virulence Microarray ?

    OpenAIRE

    Rato, Márcia G.; Nerlich, Andreas; Bergmann, René; Bexiga, Ricardo; Nunes, Sandro F.; Vilela, Cristina L.; Santos-Sanches, Ilda; Chhatwal, Gursharan S.

    2011-01-01

    A custom-designed microarray containing 220 virulence genes of Streptococcus pyogenes (group A Streptococcus [GAS]) was used to test group C Streptococcus dysgalactiae subsp. dysgalactiae (GCS) field strains causing bovine mastitis and group C or group G Streptococcus dysgalactiae subsp. equisimilis (GCS/GGS) isolates from human infections, with the latter being used for comparative purposes, for the presence of virulence genes. All bovine and all human isolates carried a fraction of the 220 ...

  4. Efeito antimicrobiano in vitro do extrato de jabuticaba [Myrciaria cauliflora (Mart.)O.Berg.] sobre Streptococcus da cavidade oral / In vitro antimicrobial effect of jabuticaba [Myrciaria cauliflora (Mart.)O.Berg] extract on Streptococcus from the oral cavity

    Scientific Electronic Library Online (English)

    C.M., Carvalho; M.R., Macedo-Costa; M.S.V., Pereira; J.S., Higino; L.F.P.C., Carvalho; L.J., Costa.

    Full Text Available Este estudo avaliou a ação do extrato etanólico das folhas de Myrciaria cauliflora (Mart.)O.Berg. sobre três culturas de Streptococcus formadoras do biofilme dental. A atividade antimicrobiana foi determinada pelo método de difusão em meio sólido. Os dados obtidos foram satisfatórios para todas as e [...] spécies ensaiadas (Streptococcus mutans ATCC 25175, Streptococcus sobrinus ATCC 27609 e Streptococcus sanguis ATCC 10557) gerando halos de inibição quando utilizado o extrato puro e diluições 1:2 e 1:4. Os resultados incentivam a realização de novas pesquisas que viabilizem a produção de compostos com finalidade terapêutica que possam ser utilizados clinicamente na odontologia. Abstract in english This study evaluated the action of ethanolic extract of Myrciaria cauliflora (Mart.)O.Berg leaves on three Streptococcus cultures from dental plaque. Antimicrobial activity was assessed by agar-well diffusion method. The obtained data were satisfactory for all assayed species (Streptococcus mutans A [...] TCC 25175, Streptococcus sobrinus ATCC 27609 and Streptococcus sanguis ATCC 10557) yielding inhibition halos when the pure extract and 1:2 and 1:4 dilutions were used. These results encourage new studies for the production of therapeutic compounds to be used in clinical dentistry.

  5. Efeito antimicrobiano in vitro do extrato de jabuticaba [Myrciaria cauliflora (Mart.O.Berg.] sobre Streptococcus da cavidade oral In vitro antimicrobial effect of jabuticaba [Myrciaria cauliflora (Mart.O.Berg] extract on Streptococcus from the oral cavity

    Directory of Open Access Journals (Sweden)

    C.M. Carvalho

    2009-01-01

    Full Text Available Este estudo avaliou a ação do extrato etanólico das folhas de Myrciaria cauliflora (Mart.O.Berg. sobre três culturas de Streptococcus formadoras do biofilme dental. A atividade antimicrobiana foi determinada pelo método de difusão em meio sólido. Os dados obtidos foram satisfatórios para todas as espécies ensaiadas (Streptococcus mutans ATCC 25175, Streptococcus sobrinus ATCC 27609 e Streptococcus sanguis ATCC 10557 gerando halos de inibição quando utilizado o extrato puro e diluições 1:2 e 1:4. Os resultados incentivam a realização de novas pesquisas que viabilizem a produção de compostos com finalidade terapêutica que possam ser utilizados clinicamente na odontologia.This study evaluated the action of ethanolic extract of Myrciaria cauliflora (Mart.O.Berg leaves on three Streptococcus cultures from dental plaque. Antimicrobial activity was assessed by agar-well diffusion method. The obtained data were satisfactory for all assayed species (Streptococcus mutans ATCC 25175, Streptococcus sobrinus ATCC 27609 and Streptococcus sanguis ATCC 10557 yielding inhibition halos when the pure extract and 1:2 and 1:4 dilutions were used. These results encourage new studies for the production of therapeutic compounds to be used in clinical dentistry.

  6. Group B Streptococcus pili mediate adherence to salivary glycoproteins.

    Science.gov (United States)

    Brittan, Jane L; Nobbs, Angela H

    2015-05-01

    Group B Streptococcus (GBS) is a leading cause of neonatal sepsis, pneumonia and meningitis, and is responsible for a rising number of severe invasive infections in adults. For all disease manifestations, colonisation is a critical first step. GBS has frequently been isolated from the oropharynx of neonates and adults. However, little is understood about the mechanisms of GBS colonisation at this site. In this study it is shown that three GBS strains (COH1, NEM316, 515) have capacity to adhere to human salivary pellicle. Heterologous expression of GBS pilus island (PI) genes in Lactococcus lactis to form surface-expressed pili demonstrated that GBS PI-2a and PI-1 pili bound glycoprotein-340 (gp340), a component of salivary pellicle. By contrast, PI-2b pili did not interact with gp340. The variation was attributable to differences in capacities for backbone and ancillary protein subunits of each pilus to bind gp340. Furthermore, while GBS strains were aggregated by fluid-phase gp340, this mechanism was not mediated by pili, which displayed specificity for immobilised gp340. Thus pili may enable GBS to colonise the soft and hard tissues of the oropharynx, while evading an innate mucosal defence, with implications for risk of progression to severe diseases such as meningitis and sepsis. PMID:25576026

  7. Screening for Group B Streptococcus: A Private Hospital's Experience

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    Oscar Wehmanen

    2010-01-01

    Full Text Available Objective. To assess the effect of universal screening and administration of intrapartum antibiotic prophylaxis to prevent early-onset neonatal GBS sepsis at a private tertiary care hospital since issuance of the 2002 CDC guidelines for preventing perinatal GBS disease. Methods. Retrospective analysis of women delivering between January 1, 2003 and December 31, 2004 at a private tertiary care hospital in Houston, Texas. The percentage of women screened, GBS positive women receiving intrapartum antibiotic prophylaxis, and infants developing early-onset GBS sepsis were determined. Results. 2,108 women delivered 2,135 infants with 1,874 (89% screened for GBS. Of those screened, 1,322 (71% tested negative and 552 (29% tested positive for GBS. In this analysis of 2,135 infants, 3 (0.94 cases/1,000 live births were diagnosed with invasive GBS sepsis. Conclusion. High rates of screening of pregnant women for GBS colonization and use of intrapartum antibiotic prophylaxis for GBS carriers can be achieved in a private tertiary care hospital setting. “Synopsis: High screening rates for group B streptococcus in a private tertiary care hospital reduce the incidence of maternal and early onset neonatal GBS infection.”

  8. Group B Streptococcus vaccine: state of the art.

    Science.gov (United States)

    Nuccitelli, Annalisa; Rinaudo, C Daniela; Maione, Domenico

    2015-05-01

    Group B Streptococcus (GBS) is cause of neonatal invasive diseases as well as of severe infections in the elderly and immune-compromised patients. Despite significant advances in the prevention and treatment of neonatal disease, sepsis and meningitis caused by GBS still represent a significant public health care concern globally and additional prevention and therapeutic strategies against infection are highly desirable. The introduction of national recommended guidelines in several countries to screen pregnant women for GBS carriage and the use of antibiotics during delivery significantly reduced disease occurring within the first hours of life (early-onset disease), but it has had no effect on the late-onset diseases occurring after the first week and is not feasible in most countries. Availability of an effective vaccine against GBS would provide an effective means of controlling GBS disease. This review provides an overview of the burden of invasive disease caused by GBS in infants and adults, and highlights the strategies for the development of an effective vaccine against GBS infections. PMID:26288735

  9. Diversity of Streptococcus mutans strains in bacterial interspecies interactions.

    Science.gov (United States)

    Li, Xiaolan; Hoogenkamp, Michel A; Ling, Junqi; Crielaard, Wim; Deng, Dong Mei

    2014-02-01

    Biofilms are matrix-enclosed microbial population adhere to each other and to surfaces. Compared to planktonic bacterial cells, biofilm cells show much higher levels of antimicrobial resistance. We aimed to investigate Streptococcus mutans strain diversity in biofilm formation and chlorhexidine (CHX) resistance of single S. mutans and dual S. mutans-Enterococcus faecalis biofilms. Four clinical S. mutans strains (C180-2, C67-1, HG723 and UA159) formed 24-h biofilms with or without an E. faecalis strain. These biofilms were treated for 10?min with 0.025% CHX. Biofilm formation, CHX resistance and S.mutans-E. faecalis interactions were evaluated by biomass staining, resazurin metabolism, viable count and competition agar assays. The main finding is that the presence of E. faecalis generally reduced all dual-species biofilm formation, but the proportions of S. mutans in the dual-species biofilms as well as CHX resistance displayed a clear S. mutans strain dependence. In particular, decreased resistance against CHX was observed in dual S. mutans C67-1 biofilms, while increased resistance was found in dual S. mutans UA159 biofilms. In conclusion, the interaction of S. mutans with E. faecalis in biofilms varies between strains, which underlines the importance of studying strain diversity in inter-species virulence modulation and biofilm antimicrobial resistance. PMID:23456658

  10. Characterization and Streptococcus mutans adhesion on air polishing dentin.

    Science.gov (United States)

    Tada, Kazuhiro; Oda, Hirotake; Inatomi, Michitomo; Sato, Soh

    2014-07-01

    Air polishing is known as an effective and time saving tooth cleaning method. However, this method increased surface roughness and bacterial adhesion on dentin surface. The aim of this study was to characterize and examine Streptococcus mutans adhesion on dentin surface after air polishing as compared to the conventional method. The dentin blocks (4 × 4 × 1 mm) were polished by a rubber cup with polishing material (Polishing) and air-polished by 25 ?m glycine (G25), 65 ?m glycine (G65), and 65 ?m sodium bicarbonate (NHC65) microparticles. Surface roughness (Ra) was measured by a laser electron microscope. The amount of adhered S. mutans was quantified using a resazurin reduction assay (alamarBlue(®)). The Ra of G25 and G65 was significantly (p Polishing. However, there was no significant difference in S. mutans adhesion among Polishing, G25, and G65, while NHC65 showed significantly (p polishing using glycine microparticles conditioned S. mutans adhesion on dentin surface in a similar fashion than the conventional method, and less than air polishing using sodium bicarbonate microparticles. PMID:23744363

  11. Purification and preliminary crystallization of alanine racemase from Streptococcus pneumoniae

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    Im Hookang

    2007-05-01

    Full Text Available Abstract Background Over the past fifteen years, antibiotic resistance in the Gram-positive opportunistic human pathogen Streptococcus pneumoniae has significantly increased. Clinical isolates from patients with community-acquired pneumonia or otitis media often display resistance to two or more antibiotics. Given the need for new therapeutics, we intend to investigate enzymes of cell wall biosynthesis as novel drug targets. Alanine racemase, a ubiquitous enzyme among bacteria and absent in humans, provides the essential cell wall precursor, D-alanine, which forms part of the tetrapeptide crosslinking the peptidoglycan layer. Results The alanine racemases gene from S. pneumoniae (alrSP was amplified by PCR and cloned and expressed in Escherichia coli. The 367 amino acid, 39854 Da dimeric enzyme was purified to electrophoretic homogeneity and preliminary crystals were obtained. Racemic activity was demonstrated through complementation of an alr auxotroph of E. coli growing on L-alanine. In an alanine racemases photometric assay, specific activities of 87.0 and 84.8 U mg-1 were determined for the conversion of D- to L-alanine and L- to D-alanine, respectively. Conclusion We have isolated and characterized the alanine racemase gene from the opportunistic human pathogen S. pneumoniae. The enzyme shows sufficient homology with other alanine racemases to allow its integration into our ongoing structure-based drug design project.

  12. High-resolution CT findings in Streptococcus milleri pulmonary infection

    International Nuclear Information System (INIS)

    Aim: To assess pulmonary high-resolution computed tomography (CT) findings in patients with acute Streptococcus milleri pulmonary infection. Materials and methods: Sixty consecutive patients with acute S. milleri pneumonia who had undergone high-resolution CT chest examinations between January 2004 and March 2010 were retrospectively identified. Twenty-seven patients with concurrent infections were excluded. The final study group comprised 33 patients (25 men, 8 women; aged 20–88 years, mean 63.1 years) with S. milleri infection. The patients' clinical findings were assessed. Parenchymal abnormalities, enlarged lymph nodes, and pleural effusion were evaluated on high-resolution CT. Results: Underlying conditions included malignancy (n = 15), a smoking habit (n = 11), and diabetes mellitus (n = 8). CT images of all patients showed abnormal findings, including ground-glass opacity (n = 24), bronchial wall thickening (n = 23), consolidation (n = 17), and cavities (n = 7). Pleural effusion was found in 18 patients, and complex pleural effusions were found in seven patients. Conclusion: Pulmonary infection caused by S. milleri was observed mostly in male patients with underlying conditions such as malignancy or a smoking habit. The CT findings in patients with S. milleri consisted mainly of ground-glass opacity, bronchial wall thickening, pleural effusions, and cavities

  13. The post-vaccine microevolution of invasive Streptococcus pneumoniae

    Science.gov (United States)

    Cremers, Amelieke J. H.; Mobegi, Fredrick M.; de Jonge, Marien I.; van Hijum, Sacha A. F. T.; Meis, Jacques F.; Hermans, Peter W. M.; Ferwerda, Gerben; Bentley, Stephen D.; Zomer, Aldert L.

    2015-01-01

    The 7-valent pneumococcal conjugated vaccine (PCV7) has affected the genetic population of Streptococcus pneumoniae in pediatric carriage. Little is known however about pneumococcal population genomics in adult invasive pneumococcal disease (IPD) under vaccine pressure. We sequenced and serotyped 349 strains of S. pneumoniae isolated from IPD patients in Nijmegen between 2001 and 2011. Introduction of PCV7 in the Dutch National Immunization Program in 2006 preluded substantial alterations in the IPD population structure caused by serotype replacement. No evidence could be found for vaccine induced capsular switches. We observed that after a temporary bottleneck in gene diversity after the introduction of PCV7, the accessory gene pool re-expanded mainly by genes already circulating pre-PCV7. In the post-vaccine genomic population a number of genes changed frequency, certain genes became overrepresented in vaccine serotypes, while others shifted towards non-vaccine serotypes. Whether these dynamics in the invasive pneumococcal population have truly contributed to invasiveness and manifestations of disease remains to be further elucidated. We suggest the use of whole genome sequencing for surveillance of pneumococcal population dynamics that could give a prospect on the course of disease, facilitating effective prevention and management of IPD. PMID:26492862

  14. Essential oil of Curcuma longa inhibits Streptococcus mutans biofilm formation.

    Science.gov (United States)

    Lee, Kwang-Hee; Kim, Beom-Su; Keum, Ki-Suk; Yu, Hyeon-Hee; Kim, Young-Hoi; Chang, Byoung-Soo; Ra, Ji-Young; Moon, Hae-Dalma; Seo, Bo-Ra; Choi, Na-Young; You, Yong-Ouk

    2011-01-01

    Curcuma longa (C. longa) has been used as a spice in foods and as an antimicrobial in Oriental medicine. In this study, we evaluated the inhibitory effects of an essential oil isolated from C. longa on the cariogenic properties of Streptococcus mutans (S. mutans), which is an important bacterium in dental plaque and dental caries formation. First, the inhibitory effects of C. longa essential oil on the growth and acid production of S. mutans were tested. Next, the effect of C. longa essential oil on adhesion to saliva-coated hydroxyapatite beads (S-HAs) was investigated. C. longa essential oil inhibited the growth and acid production of S. mutans at concentrations from 0.5 to 4 mg/mL. The essential oil also exhibited significant inhibition of S. mutans adherence to S-HAs at concentrations higher than 0.5 mg/mL. S. mutans biofilm formation was determined by scanning electron microscopy (SEM) and safranin staining. The essential oil of C. longa inhibited the formation of S. mutans biofilms at concentrations higher than 0.5 mg/mL. The components of C. longa essential oil were then analyzed by GC and GC-MS, and the major components were ?-turmerone (35.59%), germacrone (19.02%), ?-zingiberene (8.74%), ?r-turmerone (6.31%), trans-?-elemenone (5.65%), curlone (5.45%), and ?-sesquiphellandrene (4.73%). These results suggest that C. longa may inhibit the cariogenic properties of S. mutans. PMID:22416707

  15. Antibiotic Susceptibilities and Serotyping of Clinical Streptococcus Agalactiae Isolates

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    Altay Atalay

    2011-11-01

    Full Text Available Objective: Streptococcus agalactiae (Group B streptococci, GBS are frequently responsible for sepsis and meningitis seen in the early weeks of life. GBS may cause perinatal infection and premature birth in pregnant women. The aim of this study was to serotype GBS strains isolated from clinical samples and evaluate their serotype distribution according to their susceptibilities to antibiotics and isolation sites. Material and Methods: One hundred thirty one S. agalactiae strains isolated from the clinical samples were included in the study. Of the strains, 99 were isolated from urine, 20 from soft tissue, 10 from blood and 2 from vaginal swab. Penicillin G and ceftriaxone susceptibilities of GBS were determined by the agar dilution method. Susceptibilities to erythromycin, clindamycin, vancomycin and tetracycline were determined by the Kirby-Bauer method according to CLSI criteria. Serotyping was performed using the latex aglutination method using specific antisera (Ia, Ib, II-VIII. Results: While in 131 GBS strains, serotypes VII and VIII were not detected, the most frequently isolated serotypes were types Ia (36%, III (30.5% and II (13% respectively. Serotype Ia was the most frequently seen serotype in all samples. All GBS isolates were susceptible to penicilin G, ceftriaxone and vancomycin. Among the strains, tetracycline, erythromycin and clindamycin resistance rates were determined as 90%, 14.5%, and 13% respectively. Conclusion: Penicillin is still the first choice of treatment for the infections with all serotypes of S. agalactiae in Turkey.

  16. Conservative sex and the benefits of transformation in Streptococcus pneumoniae.

    Science.gov (United States)

    Engelmoer, Daniel J P; Donaldson, Ian; Rozen, Daniel E

    2013-01-01

    Natural transformation has significant effects on bacterial genome evolution, but the evolutionary factors maintaining this mode of bacterial sex remain uncertain. Transformation is hypothesized to have both positive and negative evolutionary effects on bacteria. It can facilitate adaptation by combining beneficial mutations into a single individual, or reduce the mutational load by exposing deleterious alleles to natural selection. Alternatively, it may expose transformed cells to damaged or otherwise mutated environmental DNA and is energetically expensive. Here, we examine the long-term effects of transformation in the naturally competent species Streptococcus pneumoniae by evolving populations of wild-type and competence-deficient strains in chemostats for 1000 generations. Half of these populations were exposed to periodic mild stress to examine context-dependent benefits of transformation. We find that competence reduces fitness gain under benign conditions; however, these costs are reduced in the presence of periodic stress. Using whole genome re-sequencing, we show that competent populations fix fewer new mutations and that competence prevents the emergence of mutators. Our results show that during evolution in benign conditions competence helps maintain genome stability but is evolutionary costly; however, during periods of stress this same conservativism enables cells to retain fitness in the face of new mutations, showing for the first time that the benefits of transformation are context dependent. PMID:24244172

  17. Streptococcus mutans attachment on a cast titanium surface

    Scientific Electronic Library Online (English)

    Sicknan Soares da, Rocha; Adilson César Abreu, Bernardi; Antônio Carlos, Pizzolitto; Gelson Luis, Adabo; Elisabeth Loshchagin, Pizzolitto.

    2009-03-01

    Full Text Available This study examined by means of scanning electron microscopy (SEM), the attachment of Streptococcus mutans and the corrosion of cast commercially pure titanium, used in dental dentures. The sample discs were cast in commercially pure titanium using the vacuum-pressure machine (Rematitan System). The [...] surfaces of each metal were ground and polished with sandpaper (#300-4000) and alumina paste (0.3 µm). The roughness of the surface (Ra) was measured using the Surfcorder rugosimeter SE 1700. Four coupons were inserted separately into Falcon tubes contained Mueller Hinton broth inoculated with S. mutans ATCC 25175 (10(9) cuf) and incubated at 37 °C. The culture medium was changed every three days during a 365-day period, after which the falcons were prepared for observations by SEM. The mean Ra value of CP Ti was 0.1527 µm. After S. mutans biofilm removal, pits of corrosion were observed. Despite the low roughness, S. mutans attachment and biofilm formation was observed, which induced a surface corrosion of the cast pure titanium.

  18. Streptococcus mutans attachment on a cast titanium surface

    Directory of Open Access Journals (Sweden)

    Sicknan Soares da Rocha

    2009-03-01

    Full Text Available This study examined by means of scanning electron microscopy (SEM, the attachment of Streptococcus mutans and the corrosion of cast commercially pure titanium, used in dental dentures. The sample discs were cast in commercially pure titanium using the vacuum-pressure machine (Rematitan System. The surfaces of each metal were ground and polished with sandpaper (#300-4000 and alumina paste (0.3 µm. The roughness of the surface (Ra was measured using the Surfcorder rugosimeter SE 1700. Four coupons were inserted separately into Falcon tubes contained Mueller Hinton broth inoculated with S. mutans ATCC 25175 (10(9 cuf and incubated at 37 °C. The culture medium was changed every three days during a 365-day period, after which the falcons were prepared for observations by SEM. The mean Ra value of CP Ti was 0.1527 µm. After S. mutans biofilm removal, pits of corrosion were observed. Despite the low roughness, S. mutans attachment and biofilm formation was observed, which induced a surface corrosion of the cast pure titanium.

  19. The anti-biofouling effect of polyphenols against Streptococcus mutans.

    Science.gov (United States)

    Sendamangalam, Varunraj; Choi, One Kyun; Kim, Dongshik; Seo, Youngwoo

    2011-01-01

    Biofouling is a process of surface colonization by microorganisms through cell adhesion and production of extracellular polymers (polysaccharides and proteins). It often causes serious problems in the chemical, medical and pharmaceutical industries. Recently, it was demonstrated that some natural phenolic compounds found in plants and vegetables have an antibiofouling effect, reducing formation of biofilm by Gram-negative bacteria. In this study, Streptococcus mutans, a Gram-positive bacterium was investigated for the antibiofouling effect of polyphenols. It was hypothesized that the two enzymes, glucosyltransferase and fructosyltransferase, produced by S. mutans, would be inhibited by the natural phenolic compounds. When these two enzymes were inhibited, less (or no) biofilms were formed. Enzymes were separated from a S. mutans culture medium, and their activities were measured with five different polyphenols using microtiter-plates and high-performance liquid chromatography. The results of minimum inhibitory concentration (MIC) were used to determine the enzyme inhibition effect of polyphenols on biofilm formation without killing the cells. Most of the polyphenols used showed considerable reduction of biofilm formation. Gallic acid and tannic acid showed significant enzyme inhibition effects below their MICs. PMID:21104475

  20. emm Gene Polymorphism among Streptococcus pyogenes Isolated from

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    Mollaii Hamid

    2009-10-01

    Full Text Available DNA sequencing is the most conclusive method for emm (M protein gene typing of Streptococcus pyogenes. This method is not a feasible approach in developing countries where streptococcal infection is widespread among adults and children. Alternatively the PCR-RFLP has the potential for rapid screening of different types of S. pyogenes. To document the emm type distribution of S. pyogenes in a group of patients suffering from pharyngitis, the restriction fragment length polymorphism (RFLP profile of 50 isolates were analyzed. By using Hae III+ HincII (double digestion and Dde I restriction enzymes and based on RFLP, the profile patterns of the isolates were compared. The analysis of data identified 15 distinct RFLP patterns for Hae III+ Hinc II and 13 patterns for Dde I. They differ from each other by at least one band. Although the number of isolates was not sufficient to make any epidemiological conclusion, but the finding demonstrated that the S. pyogenes population among pateints was heterogeneous. Regarding the PCR method, we managed to improve the results by modification of CDC protocol in three different ways. This study was conducted in normal circumstances when pharyngitis was at the peak seasonal incident. However emm amplicon restriction digest analysis is a valuable tool for rapid analysis of S. pyogenes infection in more important situation like outbreaks and in selected type of study like consideration of nosocomial infection.

  1. Xylitol and capsular gene expression in Streptococcus pneumoniae.

    Science.gov (United States)

    Kurola, Paula; Tapiainen, Terhi; Kaijalainen, Tarja; Uhari, Matti; Saukkoriipi, Annika

    2009-11-01

    Xylitol is a sugar alcohol that inhibits the growth and adherence of Streptococcus pneumoniae. In clinical trials, xylitol has been shown to decrease the occurrence of acute otitis media in day-care children but did not decrease nasopharyngeal carriage of the pneumococci. It has also been shown that xylitol affects the ultrastructure of the pneumococcal capsule. Here, it was hypothesized that xylitol might affect the expression of pneumococcal capsular genes. Capsule gene expression levels were studied in 24 clinical pneumococcal isolates and one ATCC strain (49619) by using a real-time RT-PCR method targeting the mRNA of the second gene of the pneumococcal capsular locus, the cpsB gene. The isolates were exposed to 5 % glucose, 5 % xylitol and control medium (brain heart infusion medium containing 10 % fetal bovine serum) for 2 h. cpsB gene expression levels were measured by using a relative quantification method with calibrator normalization where the 16S rRNA gene of pneumococcus was used as a reference. Exposure to xylitol lowered cpsB gene expression levels significantly compared with those in the control (P=0.035) and glucose (P=0.011) media. This finding supports previous results where exposure to xylitol changed the ultrastructure of the pneumococcal capsule and could explain further the high clinical efficacy of xylitol in preventing otitis media. PMID:19589898

  2. Streptococcus bovis endocarditis: analysis of cases between 2005 and 2014

    Scientific Electronic Library Online (English)

    Renato, Mello; Marisa da Silva, Santos; Wilma, Golebiosvki; Clara, Weksler; Cristiane, Lamas.

    2015-04-01

    Full Text Available Background: Streptococcus bovis is a classical etiology of endocarditis and is associated with colonic lesions. No series of cases from Brazil has been described. Objectives: To describe aspects of S. bovis endocarditis. Methods: This is a case series of patients admitted to a cardiac surgery refer [...] ral center, during the years 2005-2014. Clinical, laboratory, echochardiographic, colonoscopic, treatment, surgical and outcome variables were studied. Results: Nine patients with S. bovis endocarditis were included; all cases ful?lled the modi?ed Duke criteria. Incidence was 8/220 (4%) in years 2006-2014. There were seven male and two female patients; mean age was 56.7 years, standard deviation 13.4. All patients had native aortic valve involvement. Presentation was subacute in 7/9 (71%). Fever was present in 7/9 (77.7%), embolic lesions to solid organs occurred in three, and perivalvular abscess in two patients. All echocardiograms showed moderate to severe valvular regurgitation and vegetations. Microcytic anemia was seen in 7/7 patients. Colonoscopy showed abnormal ?ndings in 7/9 (77.7%). Surgery was indicated for 6/9 patients due to acute aortic regurgitation and left ventricular failure. All patients were discharged home. Conclusions: S. bovis most frequently affected the aortic valve of male patients. Colon disease was frequent. Surgery was indicated frequently due to hemodynamic compromise.

  3. [Invasive Streptococcus pneumoniae infection (Austrian syndrome): a case report].

    Science.gov (United States)

    Echeverri, Daniel; Vargas, María de los Ángeles; Matta, Lorena; Rosso, Fernando; Segura, Janier Daniel

    2015-01-01

    Austrian syndrome is defined as the triad consisting of pneumonia, endocarditis and meningitis due to invasive Streptococcus pneumoniae infection. Few case reports have been reported since its first description in 1975 by Robert Austrian, mainly because it is rarely observed. Below we report the case of a 61 year-old male patient who presented with bacterial meningitis due S. pneumoniae followed by bacterial pneumonia and severe mitral regurgitation, associated with four vegetations on the atrial surface of the posterior mitral leaflet; in addition, there was rupture and prolapse of its middle scallop. The S. pneumoniae bacterium was isolated from cerebrospinal fluid and blood cultures. In consequence, the patient was given broad-spectrum antibiotic therapy and had an early valve replacement performed, obtaining a good clinical outcome. The key prognostic factor of the Austrian syndrome is determined by the damage of cardiac valves, particularly in patients with a compromised aortic valve; hence, it is necessary to identify the degree of valve injury and define surgical and antibiotic treatment on a timely fashion. However, in subacute, less frequent clinical cases where the mitral valve is the main valve compromised, usually a directed antibiotic therapy associated with advanced support measures are sufficient to control this infection. PMID:26148029

  4. Inhibition of dextransucrase activity in Streptococcus mutans by plant phenolics.

    Science.gov (United States)

    Goyal, Dimple; Sharma, Sukesh; Mahmood, Akhtar

    2013-02-01

    Streptococcus mutans is responsible for causing dental caries in humans and utilizes sucrose for its growth. The dextransucrase (EC 2.4.1.5) is responsible for sucrose metabolism, which exhibits both hydrolytic and glucosyltransferase activities. In this study, we examined the effects of the plant phenols, namely gallic, tannic and syringic acids and aqueous extracts of certain traditionally used chewing sticks (Acacia arabica, Azadirachta indica, Pongamia pinnata and Salvadora persica) for prevention of dental caries on hydrolytic activity of dextransucrsae in S. mutans. Gallic acid (4-5 mM) produced 80-90% inhibition of the enzyme, while tannic acid (0.2 mM) and syringic acid (5 mM) inhibited the enzyme activity 80% and 48%, respectively in vitro. The aqueous extracts of chewing sticks produced 35-40% inhibition of dextransucrase activity at 5 mg phenol concentration. Kinetic analysis revealed mixed-type of enzyme inhibition by polyphenols, where both K(m) and V(max) were altered. The value of K(i) for tannic, gallic and syringic acids were 0.35, 1.6 and 1.94 mM, respectively. The enzyme inhibition by polyphenols was optimum at pH 7-7.5, while by plant extract was maximum at pH 5-6. These results suggest that plant polyphenols may find potential applications in the prevention and control of dental caries by inhibiting dextransucrase activity in S. mutans. PMID:23617074

  5. Catechin-incorporated dental copolymers inhibit growth of Streptococcus mutans

    Scientific Electronic Library Online (English)

    Alexandra, Mankovskaia; Celine M., Levesque; Anuradha, Prakki.

    2013-04-01

    Full Text Available Objective: To test the inhibitory growth activity of green tea catechin incorporated into dental resins compared to resins containing the broad-spectrum antimicrobial compound chlorhexidine against Streptococcus mutans in vitro. Material and Methods: The minimum inhibitory concentrations (MICs) [...] of epigallocatechin-gallate (EGCg) and chlorhexidine (CHX) were determined according to the microdilution method. Resin discs (5 mm × 3 mm) were prepared from Bis-GMA/TEGDMA (R1) and Bis-GMA/CH3Bis-GMA (R2) comonomers (n=9) containing: a) no drug, b) EGCg, c) CHX. Two concentrations of each drug (0.5× MIC and 1× MIC) were incorporated into the resin discs. Samples were individually immersed in a bacterial culture and incubated for 24 h at 37°C under constant agitation. Cell viability was assessed by counting the number of colonies on replica agar plates. Statistical analysis was performed using one-way ANOVA, Tukey and Student t-tests (?=0.05). Results: Both resins containing EGCg and CHX showed a significant inhibition of bacterial growth at both concentrations tested (p

  6. Streptococcus mutans-derived extracellular matrix in cariogenic oral biofilms

    Science.gov (United States)

    Klein, Marlise I.; Hwang, Geelsu; Santos, Paulo H. S.; Campanella, Osvaldo H.; Koo, Hyun

    2015-01-01

    Biofilms are highly structured microbial communities that are enmeshed in a self-produced extracellular matrix. Within the complex oral microbiome, Streptococcus mutans is a major producer of extracellular polymeric substances including exopolysaccharides (EPS), eDNA, and lipoteichoic acid (LTA). EPS produced by S. mutans-derived exoenzymes promote local accumulation of microbes on the teeth, while forming a spatially heterogeneous and diffusion-limiting matrix that protects embedded bacteria. The EPS-rich matrix provides mechanical stability/cohesiveness and facilitates the creation of highly acidic microenvironments, which are critical for the pathogenesis of dental caries. In parallel, S. mutans also releases eDNA and LTA, which can contribute with matrix development. eDNA enhances EPS (glucan) synthesis locally, increasing the adhesion of S. mutans to saliva-coated apatitic surfaces and the assembly of highly cohesive biofilms. eDNA and other extracellular substances, acting in concert with EPS, may impact the functional properties of the matrix and the virulence of cariogenic biofilms. Enhanced understanding about the assembly principles of the matrix may lead to efficacious approaches to control biofilm-related diseases. PMID:25763359

  7. PREVALENCIA DE COLONIZACION POR STREPTOCOCCUS AGALACTIAE (GRUPO B) EN EL TERCER TRIMESTRE DEL EMBARAZO. EVALUACION DEL CULTIVO SELECTIVO. EXPERIENCIA EN 2192 PACIENTES

    Scientific Electronic Library Online (English)

    Fernando, Abarzúa C.; Ana María, Guzmán; Cristián, Belmar; Jorge, Becker; Patricia, García; Alonso, Rioseco; Enrique, Oyarzún.

    Full Text Available Streptococcus grupo B (SGB) es el principal agente bacteriano en sepsis neonatal precoz. La infección generalmente es adquirida durante el trabajo de parto en hijos de madres colonizadas. La prevalencia de colonización reportada es variable (2 a 34%), encontrándose las cifras más altas cuando se uti [...] liza muestra vaginal-perianal y medios de cultivo selectivos. Los objetivos del estudio fueron evaluar la prevalencia de SGB en el embarazo, y conocer el rendimiento del cultivo selectivo versus el cultivo en medio no selectivo. En 2192 embarazadas de 35-37 semanas de gestación ingresadas al estudio, la prevalencia encontrada utilizando medio selectivo fue de un 19,8%, porcentaje que baja a un 12,7% si se analizan los datos sólo a partir de medio no selectivo. La alta prevalencia de colonización en este grupo de pacientes, sugiere la necesidad de implementar el cultivo sistemático para SGB en todas las embarazadas en nuestro hospital, utilizando el medio selectivo, el cual mejora significativamente su recuperación Abstract in english Group B Streptococcus (GBS) is the most important bacterial agent in early-onset neonatal sepsis. Infection is usually acquired during labor in colonized women. Among pregnant women streptococcal colonization ranges from 2% to 34%, with highgest rates when using combined vaginal and anal culture in [...] a selective broth medium. The aim of this study was to know the GBS prevalence in pregnant women controlled in our hospital and the real improvement in GBS recovery because the use of selective media. Among 2192 pregnant women enrolled, using selective medium, we identifed GBS in 19.8% of them. With non selective medium the prevalence would have reached only 12.7%. This finding support the systematic screening for GBS in our hospital, using selective medium only

  8. PREVALENCIA DE COLONIZACION POR STREPTOCOCCUS AGALACTIAE (GRUPO B EN EL TERCER TRIMESTRE DEL EMBARAZO. EVALUACION DEL CULTIVO SELECTIVO. EXPERIENCIA EN 2192 PACIENTES

    Directory of Open Access Journals (Sweden)

    Fernando Abarzúa C.

    2002-01-01

    Full Text Available Streptococcus grupo B (SGB es el principal agente bacteriano en sepsis neonatal precoz. La infección generalmente es adquirida durante el trabajo de parto en hijos de madres colonizadas. La prevalencia de colonización reportada es variable (2 a 34%, encontrándose las cifras más altas cuando se utiliza muestra vaginal-perianal y medios de cultivo selectivos. Los objetivos del estudio fueron evaluar la prevalencia de SGB en el embarazo, y conocer el rendimiento del cultivo selectivo versus el cultivo en medio no selectivo. En 2192 embarazadas de 35-37 semanas de gestación ingresadas al estudio, la prevalencia encontrada utilizando medio selectivo fue de un 19,8%, porcentaje que baja a un 12,7% si se analizan los datos sólo a partir de medio no selectivo. La alta prevalencia de colonización en este grupo de pacientes, sugiere la necesidad de implementar el cultivo sistemático para SGB en todas las embarazadas en nuestro hospital, utilizando el medio selectivo, el cual mejora significativamente su recuperaciónGroup B Streptococcus (GBS is the most important bacterial agent in early-onset neonatal sepsis. Infection is usually acquired during labor in colonized women. Among pregnant women streptococcal colonization ranges from 2% to 34%, with highgest rates when using combined vaginal and anal culture in a selective broth medium. The aim of this study was to know the GBS prevalence in pregnant women controlled in our hospital and the real improvement in GBS recovery because the use of selective media. Among 2192 pregnant women enrolled, using selective medium, we identifed GBS in 19.8% of them. With non selective medium the prevalence would have reached only 12.7%. This finding support the systematic screening for GBS in our hospital, using selective medium only

  9. Meningoencefalitis bacteriana por Streptococcus agalactiae. Reporte de un caso / Bacterial meningoencephalitis by Streptococcus agalactiae. A case report

    Scientific Electronic Library Online (English)

    Olga María, Rodríguez Fernández; Alexis, Sanchén Casas; Magaly, Cordero Rodríguez; Jorge, Deus Cabrera.

    2008-06-01

    Full Text Available Se reporta el caso de un recién nacido de 13 días de edad, ingresado en el Hospital Pediátrico Provincial Docente «Dr. Eduardo Agramonte Pina» de Camagüey por presentar fiebre, irritabilidad y cianosis distal, además de antecedentes patológicos de conjuntivitis purulenta en ambos ojos al nacer. El e [...] studio citoquímico del líquido cefalorraquídeo fue sugestivo de meningoencefalitis bacteriana. Se trasladó a la sala de Terapia Intensiva donde presentó cinco crisis convulsivas en las primeras 48h. A las 72h de recluido se aisló del cultivo del líquido cefalorraquídeo, Streptococcus agalactiae sensible a Ceftriaxona, Amikacina y Ampicillín, con este último antimicrobiano se logró una evolución satisfactoria con negativización de los examenes citoquímico y bacteriológico del líquido cefalorraquídeo. A los 17 días de ingresado aparecieron secuelas como afectación del tercer par craneal, pulgares corticales bilaterales e hipertonía muscular de pierna derecha. Fue dado de alta a los 22 días, con seguimiento en su área de salud y diagnóstico al egreso de meningoencefalitis bacteriana por S. agalactiae debido a una sepsis ocular adquirida al paso del feto por el canal del parto materno. Se sugiere la adopción de estrategias preventivas por el personal de salud contra esta bacteria por desconocerse su impacto en nuestro medio Abstract in english A case of a newborn of 13 days of age is reported, admitted at «Dr. Eduardo Agramonte Piña» Educational Provincial Pediatric Hospital of Camagüey by presenting fever, irritability and distal cyanosis, besides pathological antecedents of purulent conjunctivitis in both eyes at born. The cytochemistry [...] study of the cerebrospinal fluid suggested bacterial meningoencephalitis. He was transferred to the Intensive Therapy room where he presented five convulsive crisis in the first 48h. To the 72h of been confined from the culture of the cerebrospinal fluid a Streptococcus agalactiae was isolated, sensitive to Ceftriaxone, Amikacin and Ampicillin, with the last antimicrobial a satisfactory evolution was achieved with negative cytochemistry and bacteriological exams of the cerebrospinal fluid. To the 17 days of been admitted after-effects appeared as affectation of the third cranial pair, bilateral cortical thumbs and muscular hypertonia of the right leg. He was hospital discharged at the 22 days, with follow-up in his health area and diagnosis at discharge of bacterial meningoencephalitis by S. agalactiae due to an ocular sepsis acquired passing the fetus through the maternal birth canal. The adoption of preventive strategies by the health staff against this bacteria is suggested by unknown its impact in our medium

  10. Infección y colonización faríngea asintomática de niños por Streptococcus pyogenes / Streptococcus pyogenes infection and asymptomatic throat carriage in children

    Scientific Electronic Library Online (English)

    Mary Alejandra, Restrepo Lozada; María Isabel, Múnera Jaramillo; Blanca Susana, Ramírez Puerta; Clara Patricia, Acuña Ramos.

    Full Text Available Objetivo: establecer la frecuencia de estreptococo beta hemolítico del grupo A (Streptococcus pyogenes) en niños, mediante una prueba rápida de inmunoensayo cromatográfico. Métodos: estudio piloto de tipo transversal en una muestra no probabilística de 144 niños entre 3 y 13 años, asistentes a centr [...] os infantiles de Medellín y su área metropolitana y a una institución educativa de Bogotá. Se tomaron muestras de garganta por frotis para la prueba rápida de S. pyogenes y se recolectó información demográfica y de antecedentes personales mediante una encuesta. Se calcularon los promedios con sus desviaciones estándar y los porcentajes de acuerdo con la naturaleza de las variables de interés. Resultados: la edad promedio del grupo fue 5,5 ± 2,8 años con distribución similar por sexo. Veintiún niños (14,6%) fueron positivos para S. pyogenes, diez de ellos fueron posibles infecciones y 11, portadores asintomáticos. De los 144 niños, 45 (31,3%) tenían síntomas faríngeos, de los cuales 10 (22,2%) tenían S. pyogenes. Un total de 99 (68,8%) niños fueron asintomáticos y 11 de estos (11,1%) presentaron prueba positiva para S. pyogenes. Discusión: la alta frecuencia de S. pyogenes en este grupo es un llamado de atención sobre la necesidad de implementar protocolos de manejo con pruebas rápidas para la detección del microorganismo. Abstract in english Objective: To establish the frecuency of Streptococcus pyogenes infection or asymptomatic carriage in a group of children, by means of a rapid antigendetection test. Methods: A cross-sectional study was carried out in a non-probabilistic sample of 144 children aged between 3 and 13 years, in two edu [...] cational institutions in Bogotá and Medellin. A single throat specimen was obtained from each child to carry out the rapid test; demographic data and information on pertinent symptoms and signs were obtained by means of a survey. Mean and standard deviation and percentages were calculated according to the nature of the variables. Results: Average age was 5.5 ± 2.8 years, with even distribution by gender. Twenty one children (14,6%) were positive for S. pyogenes; out of them, 10 had possible infection and 11 were asymptomatic throat carriers. Forty five children (31.3%) reported pharyngeal symptoms and 10 (22.2%) out of them were positive in the rapid test. Ninety nine children (68.7%) were asymptomatic and of them 11 (11.1%) were also positive. Discussion: Management protocols for S. pyogenes infection would benefit from the detection based on rapid tests.

  11. Prediction of an Essential Gene with Potential Drug Target Property in Streptococcus suis using comparative genomics

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    Aubhishek Zaman

    2012-10-01

    Full Text Available Genes that are indispensible for survival are referred to as essential gene. Due to the momentous significance of these genes for cellular activity they can be selected potentially as drug targets. Here in this study, an essential gene for Streptococcus suis was predicted using coherent statistical analysis and powerful genome comparison computational method. At first the whole genome protein scatter plot was generated and subsequently, on the basis of statistical significance, a reference genome was chosen. The parameters set forth for selecting the reference genome was- the genome of the query (Streptococcus suis and subject must fall in the same genus and yet they must vary to a good degree. Streptococcus pneumoniae was found to be suitable as the reference genome. A whole genome comparison was performed for the reference (Streptococcus pneumoniae and the query genome (Streptococcus suis and 14 conserved proteins from them were subjected to a screen for potential essential gene property. Among those 14 only one essential gene was found to be with impressive similarity score between reference and query. The essential gene encodes for a type of ‘Clp protease’. Clp proteases play major roles in degrading misfolded proteins. Results found here should help formulating a drug against Strptococcus suis which is responsible for mild to severe clinical conditions in human. However, like many other computational studies, the study has to be validated furthermore through in vitro assays for concrete proof.

  12. Antibacterial activity of Iranian medicinal plants against Streptococcus iniae isolated from rainbow trout (Oncorhynchus mykiss

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    Pirbalouti Ghasemi Abdollah

    2011-01-01

    Full Text Available Streptococcus iniae is among the major pathogens of a large number of fish species cultured in fresh and marine recirculating and net pen production systems. Ten Iranian medicinal plants were assessed for their antimicrobial activity against Streptococcus iniae isolates obtained from diseased Oncorhynchus mykiss (Salmonidae; Walbaum, 1972 collected from fish farms in Iran. The antibacterial activity of ethanol extracts of Punica granatum, Quercus branti, Glycyrrhiza glabra and essential oils of Heracleum lasiopetalum, Satureja bachtiarica, Thymus daenensis, Myrtus communis, Echinophora platyloba, Kelussia odoratissima and Stachys lavandulifolia against Steptococcus iniae was evaluated by disc diffusion and serial dilution assays. Most of the extracts and essential oils showed a relatively high antibacterial activity against Streptococcus iniae. Of the plants studied, the most active extracts were those obtained from the essential oils of Satureja bachtiarica, Echinophora platyloba, Thymus daenensis and the ethanol extract of Quercus branti. Some of the extracts were active against Streptococcus iniae. Two essential oils showed lower MIC values; Heracleum lasiopetalum (78 ?g/ml and Satureja bachtiarica (39 ?g/ml. The essential oil of Satureja bachtiarica could be an important source of antibacterial compounds against the Streptococcus iniae isolated from rainbow trout.

  13. Methodological variations in the isolation of genomic DNA from Streptococcus bacteria

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    Mônica Moreira

    2010-08-01

    Full Text Available In this work, genomic DNA of Streptococcus pyogenes, S. mutans and S. sobrinus was isolated using two methods: either using the detergent cetyltrimethylammonium bromide (CTAB at 65ºC; or by applying ultrasound to a mixture of silica and celite in CTAB. The composite method that used ultrasound was the more efficient, allowing the straightforward extraction of genomic DNA from Gram-positive bacteria with good quality and reproducibility.O gênero Streptococcus encontra-se amplamente distribuído na natureza e algumas espécies constituem a microbiota humana da cavidade bucal, como Streptococcus pyogenes, que pode estar associado a importantes doenças humanas, Streptococcus mutans e Streptococcus sobrinus, relacionados à cárie dental. O DNA genômico destas três espécies foi isolado utilizando-se dois métodos, o primeiro utilizando o detergente brometo de cetiltrimetilamônio (CTAB à 65ºC e outro associando ultra-som a uma mistura de sílica e celite em CTAB. O método que possibilitou a extração do DNA genômico das bactérias Gram positivas, com qualidade, boa reprodutibilidade fácil execução foi aquele que utilizou ultra-som associado à sílica e celite em CTAB.

  14. UJI ANTIBAKTERI SIWAK (Salvadora persica Linn. TERHADAP Streptococcus mutans (ATC31987 DAN Bacteroides melaninogenicus

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    B. Logawa

    2004-12-01

    Full Text Available Antibacterial Activity of Siwak (Salvadora persica Linn. against Streptococcus mutans (ATC31987 and Bacteroides melaninogenicus. Dental diseases with high prevalences in Indonesia and also in some other countries are periodontitis and caries. Both diseases are until now still a health problem. Bacteria causing dental diseases are forexamples Streptococcus mutans and Bacteroides melaninogenicus, which both can spread to other organs and cause fatal diseases. Salvadora persica (arak, siwak has been used for a long time ago as a tool for teeth cleanser in the Middle East, Africa and several Asian countries. In this study, we have done antibacterial tests of the extract and crystal of siwak against Streptococcus mutans and Bacteroides melaninogenicus. In determining the Minimal InhibitoryConcentration (MIC, the macro and micro dilution methods were used. The result showed that MIC of siwaks’ extract against Streptococcus mutans was 6.25%, and against Bacteroides melaninogenicus 1.56%. Minimal Inhibitory Concentration of siwaks’ crystal against Streptococcus mutans and Bacteroides melaninogenicus was 12.5%, and3.12% respectively. This study showed that the antibacterial activity of siwak’ crystal and extract were more potent against B. Melaninogenicus; it may be either that B. melaninogenicus was more susceptible than S. mutans or S. mutans was more virulent than B. melaninogenicus

  15. Methodological variations in the isolation of genomic DNA from Streptococcus bacteria

    Scientific Electronic Library Online (English)

    Mônica, Moreira; Juliana, Noschang; Ivana Froede, Neiva; Yanê, Carvalho; llma Hiroko, Higuti; Vânia Aparecida, Vicente.

    2010-08-01

    Full Text Available O gênero Streptococcus encontra-se amplamente distribuído na natureza e algumas espécies constituem a microbiota humana da cavidade bucal, como Streptococcus pyogenes, que pode estar associado a importantes doenças humanas, Streptococcus mutans e Streptococcus sobrinus, relacionados à cárie dental. [...] O DNA genômico destas três espécies foi isolado utilizando-se dois métodos, o primeiro utilizando o detergente brometo de cetiltrimetilamônio (CTAB) à 65ºC e outro associando ultra-som a uma mistura de sílica e celite em CTAB. O método que possibilitou a extração do DNA genômico das bactérias Gram positivas, com qualidade, boa reprodutibilidade fácil execução foi aquele que utilizou ultra-som associado à sílica e celite em CTAB. Abstract in english In this work, genomic DNA of Streptococcus pyogenes, S. mutans and S. sobrinus was isolated using two methods: either using the detergent cetyltrimethylammonium bromide (CTAB) at 65ºC; or by applying ultrasound to a mixture of silica and celite in CTAB. The composite method that used ultrasound was [...] the more efficient, allowing the straightforward extraction of genomic DNA from Gram-positive bacteria with good quality and reproducibility.

  16. Evaluation of effects Irsha antiseptic mouthwash on pathogen streptococcus and oral normal micro flora

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    A Azizi

    2009-01-01

    Full Text Available Introduction: Caries and periodontal diseases are two major diseases in mouth, which caused byaccumulation of microorganisms and forming dental plaque. Mouthwashes decrease dental plaque andgingiutis. Since Irsha mouthwash is commonly used, the purpose of this research was the evaluation ofthe effects of chlorhexidine mouthwash on pathogen streptococcus and mouth normal micro flora.Methods and Materials: In this experimental study, 28 selected voluntaries, based on inclusion criteria,used the Irsha antiseptic mouthwash as long for 2 weeks, twice a day, 15 cc for each time, and gargled inmouth for 30 seconds. Before and after using mouthwash, subjects were sampled. We asked them to washtheir mouth with physiologic serum; then, 1 cc saliva were collected in sterile tube and sent tomicrobiology laboratory immediately. This process repeated after 2 weeks using mouthwash. Numbers ofpathogen streptococcus colonies and mouth normal micro flora colonies before and after usingmouthwash were recorded. We also recorded malodor and teeth color changes before and after usingmouthwash. Data were analyzed using t-test and ?2.Results: Irsha mouthwash significantly decreased the number of pathogen streptococcus and 3 mouthnormal micro floras (P < 0.05; but did not affect on other mouth micro floras. Teeth color and malodorchanges were not observed after using this mouthwash in subjects of this study.Conclusion: Irsha mouthwash kill mouth pathogen streptococcus and can help subjects for controllingdental plaque.Key words: Irsha, Streptococcus, Micro flora, Malodor, Tooth color

  17. Asymptotically Optimal Agents

    CERN Document Server

    Lattimore, Tor

    2011-01-01

    Artificial general intelligence aims to create agents capable of learning to solve arbitrary interesting problems. We define two versions of asymptotic optimality and prove that no agent can satisfy the strong version while in some cases, depending on discounting, there does exist a non-computable weak asymptotically optimal agent.

  18. Complete Genome Sequence of Streptococcus agalactiae Serotype III, Multilocus Sequence Type 283 Strain SG-M1

    Science.gov (United States)

    Mehershahi, Kurosh S.; Hsu, Li Yang; Koh, Tse Hsien

    2015-01-01

    Streptococcus agalactiae (group B Streptococcus) is a common commensal strain in the human gastrointestinal tract that can also cause invasive disease in humans and other animals. We report here the complete genome sequence of S. agalactiae SG-M1, a serotype III, multilocus sequence type 283 strain, isolated from a Singaporean patient suffering from meningitis. PMID:26494662

  19. Genome evolution driven by host adaptations results in a more virulent and antimicrobial-resistant Streptococcus pneumoniae serotype 14

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    Hu Songnian

    2009-04-01

    Full Text Available Abstract Background Streptococcus pneumoniae serotype 14 is one of the most common pneumococcal serotypes that cause invasive pneumococcal diseases worldwide. Serotype 14 often expresses resistance to a variety of antimicrobial agents, resulting in difficulties in treatment. To gain insight into the evolution of virulence and antimicrobial resistance traits in S. pneumoniae from the genome level, we sequenced the entire genome of a serotype 14 isolate (CGSP14, and carried out comprehensive comparison with other pneumococcal genomes. Multiple serotype 14 clinical isolates were also genotyped by multilocus sequence typing (MLST. Results Comparative genomic analysis revealed that the CGSP14 acquired a number of new genes by horizontal gene transfer (HGT, most of which were associated with virulence and antimicrobial resistance and clustered in mobile genetic elements. The most remarkable feature is the acquisition of two conjugative transposons and one resistance island encoding eight resistance genes. Results of MLST suggested that the major driving force for the genome evolution is the environmental drug pressure. Conclusion The genome sequence of S. pneumoniae serotype 14 shows a bacterium with rapid adaptations to its lifecycle in human community. These include a versatile genome content, with a wide range of mobile elements, and chromosomal rearrangement; the latter re-balanced the genome after events of HGT.

  20. A STUDY ON IN VITRO ANTIBACTERIAL ACTIVITY OF FICUS BENGALENSIS LINN. ON DENTAL CARIES PATHOGENS STREPTOCOCCUS MUTANS AND ACTINOMYCES VISCOSUS

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    F. M. B. Prashanth, I. Kannan*, C. Sambandam, M. Jayalakshmi, R.K. Premavathy and S. Shantha

    2013-02-01

    Full Text Available The aerial roots of Ficus bengalensis Linn. were collected in and around Chennai, Tamilnadu, India They were washed, shade dried and were ground into powder. The powder was extracted with chloroform, petroleum ether, methanol and hexane. The antibacterial screening of the extracts was carried out by determining the zone of inhibition using disc diffusion method. The strains were grown to logarithmic phase in BHI broth and the inoculum was prepared by adjusting the turbidity of bacterial suspension to 0.5 McFarland’s tube. The dried extracts was dissolved in 10% Dimethyl sulphoxide (DMSO in required concentration. The sterile discs were impregnated with 20 ?l of extract. The extract discs were placed on BHI agar plates, which were previously inoculated with test strains and incubated at 37oC for 24 hours. Ampicillin disc (10?g and 10% DMSO impregnated discs were used as positive and negative controls respectively and the zones of inhibition were recorded. The Minimum inhibitory concentration was determined by agar dilution method. The results of the present study showed that the methanol and chloroform extracts of Ficus bengalensis Linn. have activity against both Streptococcus mutans and Actinomyces viscosus. From the present study it is concluded that Ficus bengalensis Linn. extracts can be used as an effective antibacterial agent against dental caries.