Resposta imune de tilápias do Nilo (Oreochromis niloticus) vacinadas contra Streptococcus agalactiae

Pós-graduação em Medicina Veterinária - FCAV

Streptococcal acute pharyngitis

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Eficácia de duas formulações de vacinas autógenas para o controle da lactococose em surubins híbridos Pseudoplatystoma corruscans x Pseudoplatystoma reticulatum

Pós-graduação em Aquicultura - FCAV

Desenvolvimento e validação de método analítico para a quantificação de teicoplanina injetável por turbidimetria

A teicoplanina é um complexo antibiótico glicopeptídico derivado do Actinoplanes teichomyceticus, ativo contra bactérias Gram-positivas resistentes a outros antibióticos. Seu espectro de ação é similar ao da vancomicina, sendo, porém mais ativo para Streptococcus faecalis e Clostridium difficile. Seu uso é indicado para profilaxia de endocardite, peritonite, osteomielite e para septicemia estafilocócica. No Brasil, a teicoplanina é comercializada sob a forma farmacêutica de pó liofilizado, que deve ser reconstituído antes da administração. O medicamento de referência é o Targocid®, produzido pelo laboratório Sanofi-Aventis, em duas apresentações, 66 mg/mL e 133 mg/mL. A teicoplanina, bem como a vancomicina, inibe a síntese da parede celular bacteriana, pois a molécula se liga ao precursor da parede D-alanil-D-alanina, formando um complexo, impedindo a ligação à porção terminal do peptidoglicano, que é o alvo das enzimas transglicolase e transpeptidase. Desse modo, não há incorporação de aminoácidos aos glicopeptídeos integrantes da parede celular das bactérias Gram-positivas. No estudo de validação, foram aplicados os parâmetros de linearidade, intervalo, precisão, sensibilidade, especificidade, exatidão e robustez. O método desenvolvido e validado para a quantificação de teicoplanina pó liofilizado foi: Ensaio microbiológico por turbidimetria na faixa de concentração de 20,0 a 80,0 μg/mL, utilizando o micro-organismo Staphylococcus epidermidis ATCC 12228 IAL 2150. Os parâmetros estudados para a validação do método turbidimétrico atenderam a todas as especificações para a adequada quantificação de teicoplanina na forma farmacêutica pó liofilizado

Ocorrência, sorotipagem e rsistência antimicrobiana de Streptococcus suis em funcionários e ambente de abatedouro de sínos

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Perfil de fatores de virulência das Escherichia coli isoladas do útero de vacas holandesas após o parto e sua relação com a microbiota uterina

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Experimentally induced anachoresis in the periapical region after root canal filling

Anachoresis is the phenomenon through which blood-borne bacteria, dyes, pigments and other materials are attracted and fixed to circumscribed areas of inflammation. This study evaluated the occurrence of anachoresis in the periapical region of dogs submitted to root canal fillings. One hundred and four roots from four dogs were endodontically treated and root canals were filled with zinc-oxide-eugenol cement. Fifty percent were filled up to the dentinocemental junction and the others were overfilled. At 120 days after root canal treatment, experimental bacteremia was induced by intravenous inoculation of 105 CFU Streptococcus pyogenes. The dogs were sacrificed 48 hours and 30 days after the bacteremia. Culture and DNA amplification by PCR revealed the presence of the inoculated bacteria just in periapical tissues of dogs sacrificed 48 hours after bacteremia and not in animals sacrificed after 30 days. AP-PCR fingerprints of recovered colonies of S. pyogenes and the presence of genetic markers of resistance to antimicrobials were similar to the inoculated strain. Endodontically treated periapices seemed to be prone to the occurrence of anachoresis and there was no relationship between the phenomenon and the level of root canal filling.

Prospecção fitoquímica de ativos em extratos e frações originados de folhas de Azadirachta indica A. JUSS. visando atividade antimicrobiana

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Imunohistoquímica em órgãos de tilápias-do-Nilo imunizadas com antígeno insolúvel de Streptococcus agalactiae

Pós-graduação em Medicina Veterinária - FCAV

Estudo do efeito modulador do macrolídeo tilosina na reação inflamatória aguda de tilápias do Nilo (Oreochromis niloticus), vacinadas e desafiadas com Streptococcus agalactiae

Pós-graduação em Medicina Veterinária - FCAV

Prevalence of beta-hemolytic Streptococcus in children with special health care needs

Pharyngotonsillitis by beta-hemolytic Streptococcus mostly affects children and imunocompromissed, being Streptococcus pyogenes (Group A) the most common agent in bacterial pharyngotonsillitis. Aim: This work targeted the research of beta-hemolytic Streptococcus Group-A (SBHGA) and No-A (SBHGNA) in the oropharynx of individuals with special health needs from the APAE (Maceio-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/trirnethoprim-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 beta-hemolytic Streptococcus 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.

Impact of the rapid antigen detection test in diagnosis and treatment of acute pharyngotonsillitis in a Pediatric emergency room

OBJECTIVE: To evaluate the impact of the routine use of rapid antigen detection test in the diagnosis and treatment of acute pharyngotonsillitis in children. METHODS: This is a prospective and observational study, with a protocol compliance design established at the Emergency Unit of the University Hospital of Universidade de São Paulo for the care of children and adolescents diagnosed with acute pharyngitis. RESULTS: 650 children and adolescents were enrolled. Based on clinical findings, antibiotics would be prescribed for 389 patients (59.8%); using the rapid antigen detection test, they were prescribed for 286 patients (44.0%). Among the 261 children who would not have received antibiotics based on the clinical evaluation, 111 (42.5%) had positive rapid antigen detection test. The diagnosis based only on clinical evaluation showed 61.1% sensitivity, 47.7% specificity, 44.9% positive predictive value, and 57.5% negative predictive value. CONCLUSIONS: The clinical diagnosis of streptococcal pharyngotonsillitis had low sensitivity and specificity. The routine use of rapid antigen detection test led to the reduction of antibiotic use and the identification of a risk group for complications of streptococcal infection, since 42.5% positive rapid antigen detection test patients would not have received antibiotics based only on clinical diagnosis.

Mastoiditis in children: a prospective, observational study comparing clinical presentation, microbiology, computed tomography, surgical findings and histology

The aim of this study was to obtain comprehensive data on clinical presentation, microbiology, computed tomography, surgical findings and histology in acute, sub-acute and chronic mastoiditis. We performed a prospective, observational study in children under 16 years of age presenting to our institution during the 2-year period beginning in April 2000. The children were examined and their condition treated in accordance with a standardized protocol elaborated by the paediatric, otolaryngology (ORL) and radiology departments. Thirty-eight patients were hospitalized (22 with acute mastoiditis, seven with sub-acute mastoiditis, nine with chronic mastoiditis). There were 30 complications present in 21 patients (55%). Streptococcus pyogenes was the most common pathogen (7/24 cases), followed by Streptococcus pneumoniae (4/24 cases). Mastoid surgery was performed in 29 patients. Histology of mastoid tissue revealed predominantly acute inflammation in two cases, mixed acute/chronic inflammation in 19 cases and predominantly chronic inflammation in seven cases. Radiologic data were evaluated retrospectively. Spiral, volume-based high-resolution (HR) computed tomography (CT) of the temporal bone had a sensitivity of 100%, specificity of 38%, positive predictive value (PPV) of 50% and negative predictive value (NPV) of 100% in detecting coalescence of mastoid trabeculae. Cranial CT with contrast had a sensitivity of 80%, specificity of 94%, PPV of 80% and NPV of 94% in identifying intra-cranial extension. Conclusion: histological evidence suggests that sub-acute/chronic infection underlies not only sub-acute and chronic mastoiditis, but most cases of acute mastoiditis as well. HR-CT of the temporal bone is effective in ruling out coalescence. Cranial CT is valuable in identifying intra-cranial extension. Cranial and HR-CT are recommended in the examination of children with mastoiditis.

T-cell epitope analysis using subtracted expression libraries (TEASEL): application to a 38-kDA autoantigen recognized by T cells from an insulin-dependent diabetic patient.

Studies on circulating T cells and antibodies in newly diagnosed type 1 diabetic patients and rodent models of autoimmune diabetes suggest that beta-cell membrane proteins of 38 kDa may be important molecular targets of autoimmune attack. Biochemical approaches to the isolation and identification of the 38-kDa autoantigen have been hampered by the restricted availability of islet tissue and the low abundance of the protein. A procedure of epitope analysis for CD4+ T cells using subtracted expression libraries (TEASEL) was developed and used to clone a 70-amino acid pancreatic beta-cell peptide incorporating an epitope recognized by a 38-kDa-reactive CD4+ T-cell clone (1C6) isolated from a human diabetic patient. The minimal epitope was mapped to a 10-amino acid synthetic peptide containing a DR1 consensus binding motif. Data base searches did not reveal the identity of the protein, though a weak homology to the bacterial superantigens SEA (Streptococcus pyogenes exotoxin A) and SEB (Staphylococcus aureus enterotoxin B) (23% identity) was evident. The TEASEL procedure might be used to identify epitopes of other autoantigens recognized by CD4+ T cells in diabetes as well as be more generally applicable to the study low-abundance autoantigens in other tissue-specific autoimmune diseases.

Mucosal and systemic immune responses to a recombinant protein expressed on the surface of the oral commensal bacterium Streptococcus gordonii after oral colonization.

To circumvent the need to engineer pathogenic microorganisms as live vaccine-delivery vehicles, a system was developed which allowed for the stable expression of a wide range of protein antigens on the surface of Gram-positive commensal bacteria. The human oral commensal Streptococcus gordonii was engineered to surface express a 204-amino acid allergen from hornet venom (Ag5.2) as a fusion with the anchor region of the M6 protein of Streptococcus pyogenes. The immunogenicity of the M6-Ag5.2 fusion protein was assessed in mice inoculated orally and intranasally with a single dose of recombinant bacteria, resulting in the colonization of the oral/pharyngeal mucosa for 10-11 weeks. A significant increase of Ag5.2-specific IgA with relation to the total IgA was detected in saliva and lung lavages when compared with mice colonized with wild-type S. gordonii. A systemic IgG response to Ag5.2 was also induced after oral colonization. Thus, recombinant Gram-positive commensal bacteria may be a safe and effective way of inducing a local and systemic immune response.