Crude extract of Jatobá leaves promotes canine osteosarcoma cell D17 proliferation.

Background and Aim: New substances for neoplasm treatment have to be carefully studied to minimize adverse effects and prevent disease progression stimulation. Jatobá is a typical tree of the Cerrado and Caatinga biome, with antifungal, antimicrobial, larvicide, antioxidant, and antiproliferative properties. This study aimed to investigate the action of the crude extract of Jatobá leaves (EBFJ) on canine osteosarcoma (CO) cells and analyze the expression of biomarkers in neoplasm progression. Materials and Methods: D17 cells were cultured and subjected to treatment with EBFJ at different concentrations (10 µg/mL; 100 µg/mL; 1000 µg/mL; 2000 µg/mL; and 5000 µg/mL) and exposure times (24 h, 48 h, and 72 h). The tetrazolium reduction assay and the immunocytochemistry technique, with anti-Bcl2, anti-p53, and anti-Ki-67 antibodies, were used to observe the effect of the extract on cell proliferation. Results: Doses of 2000 µg and 5000 µg had cell viability of 300.80% and 361.84%, respectively. The extract did not show significant cytotoxicity of samples with the control group. The confluence of cells, the number of labeled cells, and the expression of Bcl2, Ki-67, and p53 were higher in the groups treated with EBFJ, with a statistical difference from the group without treatment. Conclusion: EBFJ was not cytotoxic and had a proliferative effect on CO D17 cells. The confluence of cells, the number of labeled cells, and the expression of Bcl2, Ki-67, and p53 were higher in the groups treated with the extract.

Evolution of Streptococcus pneumoniae serotypes and penicillin susceptibility in Latin America, Sireva-Vigía Group, 1993 to 1999. PAHO Sireva-Vigía Study Group. Pan American Health Organization.

BACKGROUND: Since 1993 the Pan American Health Organization has coordinated a surveillance network with the National Reference Laboratories of Argentina, Brazil, Chile, Colombia, Mexico and Uruguay aimed at monitoring capsular types and antimicrobial susceptibility of Streptococcus pneumoniae causing invasive disease in children <6 years of age. METHODS: The surveillance system included children 6 years of age and younger with invasive disease caused by S. pneumoniae. The identification, capsular typing and susceptibility to penicillin of the isolates were conducted using a common protocol, based on standard methodologies. RESULTS: By June, 1999, 4,105 invasive pneumococcal isolates had been collected mainly from pneumonia (44.1%) and meningitis (41.1%) cases. Thirteen capsular types accounting for 86.1% of the isolates (14, 6A/6B, 5, 1, 23F, 19F, 18C, 19A, 9V, 7F, 3, 9N and 4) remained the most common types during the surveillance period. Diminished susceptibility to penicillin was detected in 28.6% of the isolates, 17.3% with intermediate and 11.3% with high level resistance. Resistance varied among countries and increased during this period in Argentina, Colombia and Uruguay. Serotypes 14 and 23F accounted for 66.6% of the resistance. CONCLUSION: These surveillance data clearly demonstrate the potential impact of the introduction of a conjugate vaccine on pneumococcal disease and the need for more judicious use of antibiotics to slow or reverse the development of antimicrobial resistance.

Decreased point prevalence of Haemophilus influenzae type b (Hib) oropharyngeal colonization by mass immunization of Brazilian children less than 5 years old with hib polyribosylribitol phosphate polysaccharide-tetanus toxoid conjugate vaccine in combination with diphtheria-tetanus toxoids-pertussis vaccine.

A protective herd effect has been described after susceptible populations of children are vaccinated with conjugate Haemophilus influenzae type b (Hib). Hib carriage was studied in children aged 6-24 months attending day care centers in two cities in southern Brazil (Curitiba and Porto Alegre). In Curitiba, routine immunization with Hib polyribosylribitol phosphate polysaccharide-tetanus toxoid conjugate vaccine (PRP-T) in combination with diphtheria-tetanus toxoids-pertussis vaccine (PRP-T/DTP) has been offered since September 1996; DTP vaccine alone is routinely given in Porto Alegre. Children in Porto Alegre (n=643) were 8 times less likely to have received adequate Hib vaccination and 4 times more likely to be Hib carriers than children in Curitiba (n=647; i.e., point prevalence of oropharyngeal colonization, 4.8% vs. 1.2%). Point prevalence of carriage with non-type b or other nontypeable Hi was similar in children of both cities. There was a vaccination effect on carriage rates in children who received a primary 3-dose series, independent of the booster dose, suggesting that a booster may be unnecessary to induce population protection.

First confirmed case of a vancomycin-resistant Enterococcus faecium with vanA phenotype from Brazil: isolation from a meningitis case in São Paulo.

The importance of enterococci as a nosocomial etiologic agent is well documented; however, enterococci are also capable of causing a variety of community-acquired infections. Vancomycin resistance in a clinical Enterococcus isolate was first reported in 1986, and since then vancomycin-resistant enterococci (VRE) have been reported world-wide. This report describes a case of E. faecium with the VanA phenotype, isolated from meningitis in Sao Paulo, Brazil. Two E. faecium strains were isolated. One strain showed VanA phenotype, and the molecular characterization of the VanA gene was confirmed by polymerase chain reaction. The other strain was susceptible to vancomycin and teicoplanin. The authors would like to call the attention of the scientific community to this first identification of a VRE case in Sao Paulo, Brazil.

Geographic distribution of penicillin resistance of Streptococcus pneumoniae in Brazil: genetic relatedness.

From January 1993 through December 1996, 1,252 Streptococcus pneumoniae strains from different geographic regions of Brazil were studied for penicillin (Pen) susceptibility. All pneumococci were isolated from normally sterile fluids from patients, newborns to 88 years old. Pen resistance (R) had a mean rate of 15.1%, with 14.5% of strains showing intermediate level Pen-R and 0.6% showing high-level Pen-R. Similar Pen-R rates were observed in different regions of the country, in the range of 9.5% to 17.1%. A Pen-R increase was noted from 9.6% in 1993 to 20.6% in 1996. Pen-R was mostly associated to serotypes 6B, 14, 19A, and 23F (89%). Chromosomal DNA relatedness of Pen-R strains was determined by pulsed field gel electrophoresis (PFGE). High genetic diversity was identified, being represented by 27 patterns among the 92 strains. Two important features were observed: the predominance of relatively low-level Pen MIC (range 0.1-0.5 mg/L) in 86 of the 92 strains, and the presence of 60.8% as four major PFGE clusters unique to Brazil. Another feature was the geographic spread of these clusters over large distances in the country. The city of São Paulo seems to be a Pen-R focus (18.4%) in Brazil. Only two strains representing the international clone B widely spread in France, Portugal, and Spain, belonging to serotype 14, were found.

Placental transfer of IgG and IgG subclass antibodies anti-purified Escherichia coli LPS O16, O6 and O111.

We evaluated 22 paired maternal and cord sera regarding the presence of IgG and IgG subclasses against purified Escherichia coli LPS O6, O16 and O111 employing ELISA for titre and avidity analysis, isoelectric focusing associated with affinity-blotting for spectrotypic analysis, and the Western-blotting technique for recognition of the various bands in lipopolysaccharide (LPS). Levels of anti-LPS IgG antibodies in cord sera were equivalent to their respective maternal sera, showing a significant correlation (P < 0.0001). IgG1 antibody levels were higher in cord sera than in maternal sera (P < 0.005 for anti-O111, P < 0.05 for anti-O16 and P < 0.02 for anti-O6). Cord IgG2 antibody levels were not different from the maternal levels (P > 0.1). The levels of IgG3 and IgG4 were undetectable. The avidity of anti-O6 and anti-O111 IgG in 10 cord sera showed an extremely significant correlation with maternal antibody avidity (P < 0.0001). Identical patterns of recognition were found in the paired samples analysed by Western blotting. Most of the serum samples recognized the O-repetitive chains and also the region corresponding to core and lipid A. Although the antibody spectrotypes varied among individuals, paired cord and maternal serum samples showed identical patterns. Our findings suggest the occurrence of placental transfer of IgG antibodies against LPS O6, O16 and O111, mainly involving the IgG1 or IgG2 subclasses.

Prevalence of serotypes and antimicrobial resistance of streptococcus pneumoniae strains isolated from Brazilian children with invasive infections. Pneumococcal Study Group in Brazil for the SIREVA Project. Regional System for Vaccines in Latin America.

A laboratory surveillance study was developed in Brazil in 1993 to determine capsular types and antimicrobial susceptibility of Streptococcus pneumoniae strains. By studying 360 strains isolated from children with invasive infections in three different cities, 8 out of 34 types were identified as being the most prevalent and considered as the reference group for further analyses. This group comprised 77.7% of all strains studied, and includes the types 1, 5, 6A/B, 9V, 14, 19F, 19A, and 23F. The prevalence of this reference group was significantly higher among strains isolated from children with pneumonia than meningitis. Similarly, this group was more prevalent among strains isolated from children 3 to 6 years of age than from children under 2 years of age. Most strains (78.6%) were found to be susceptible to penicillin and only 1.4% showed high resistance to this antibiotic. However, intermediate resistance to penicillin was detected in 20% of the strains. This laboratory surveillance will be maintained and extended to other cities of Brazil to better define and monitor the trends of pneumococcal infections for proper control and prevention.

Antibody studies in mice of outer membrane antigens for use in an improved meningococcal B and C vaccine.

Since 1988, N. meningitidis, B:4:P1.15, ET-5 complex, has been responsible for an epidemic of meningococcal disease in Greater São Paulo, Brazil. Despite current trials to develop an effective vaccine against group B meningococci, children less than 2 years old have not been protected. It has been suggested that iron-regulated proteins (IRPs) should be considered as potential antigens for meningococcal vaccines. The vaccines under study consisted of outer-membrane vesicles depleted of lipooligosaccharide from three serogroup B strains and one serogroup C strain, IRPs, meningococcal group C polysaccharide and aluminum hydroxide. Four different protein and C polysaccharide concentrations were studied. The ELISA and bactericidal results showed a higher antibody response when 2 injections of 2.0 micrograms doses were administered. Despite higher IgG reactivity against antigen preparations containing IRPs seen in ELISA, the bactericidal activity was not increased if the target strain was grown in iron-restricted medium. The influence of addition of alkaline-detoxified lipooligosaccharide (dLOS) on immunogenicity of the vaccine was also investigated, and the dLOS provided for a more functionally specific antibody response.

Distribution of serotypes of Streptococcus pneumoniae isolated from invasive infections over a 16-year period in the greater São Paulo area, Brazil.

Capsular types of pneumococci from normally sterile body sites of 1,622 patients in Brazil were analyzed. Of 1,477 isolates from cerebrospinal fluid, 76.1% were of types represented in the currently available pneumococcal vaccine. The importance of age, time, and place in determining the optimal formulation of pneumococcal vaccine is considered.

[Serotypes of pneumococci isolated from children with pneumonia: implication of pneumococcal specific immunization]. / Sorotipos de pneumococos isolados de crianças com pneumonia: implicação com a imunização específica anti-pneumocócica.

For the 15 years from 1978 to 1992 serologic typing was performed on 124 pneumococcus isolates from children with acute pneumonia. The source of bacteria was material obtained by aspirative pulmonary punction, pleural fluid or blood; 122 capsular antigens representing groups and types could be determined. Of the 122 isolates serogrouped 14, 1, 6, 5, 4, 7, 23, 19 and 4, accounted for 25.4%; 23.8%; 13.1%; 9.0%; 4.9%; 4.9%; 4.1%; 4.1%; 4.1%; respectively, of cases. The currently available 23-valent vaccine would provide protection against 89.3% of identified pneumococci in our study, but because of its poor immunogenicity in children less than 2 years old (73.0%) they would have received reduced protection by the use of this vaccine. The distribution of pneumococci serogroups found in our study has an intermediary pattern in relation to those found at develop countries (6, 14, 18, 19, 23) and developing ones (1, 2, 3, 5, 7, 12, 46). The new conjugate vaccines, with limited number of pneumococcal groups/types, should be analysed before the introduction in different geographic areas.

Immune response of Brazilian children to a Neisseria meningitidis serogroup B outer membrane protein vaccine: comparison with efficacy.

Since 1986, serogroup B Neisseria meningitidis has caused approximately 80% of the meningococcal disease in Brazil. In 1988, an epidemic caused by N. meningitidis B:4:P1.15 was recognized in the greater São Paulo area of Brazil. The São Paulo state government decided to vaccinate children from 3 to 83 months of age with a vaccine consisting of serotype 4 outer membrane protein and group C meningococcal polysaccharide that was produced in Cuba. About 2.7 million children were vaccinated during two immunization campaigns conducted in 1989 and 1990. Because of this, a case-control study was designed to determine vaccine efficacy against group B meningococcal disease. The purpose of our study was to compare the antibody response with the protection from disease estimated from the case-control study. We measured the immune responses of vaccinees by enzyme-linked immunosorbent assay (ELISA), immunoblot, and bactericidal assay. The development of bactericidal antibodies was age dependent and in good agreement with the results of the case-control study. Only 40% of vaccinees showed fourfold or greater increases in bactericidal antibody titers after vaccination. A poor correlation between antibody levels detected by ELISA and those by bactericidal assay was found. Immunoblot analysis showed that about 50% of the serum samples with bactericidal titers higher than 1:4 were reactive with class 1 outer membrane protein. We conclude that the bactericidal assay is a good, laboratory-based, functional assay for the study of vaccine immunogenicity and that an effective solution to group B meningococcal disease remains to be demonstrated.

Induction of iron regulated proteins during normal growth of Neisseria meningitidis in a chemically defined medium.

The expression of iron regulated proteins (IRPs) in vitro has been obtained in the past by adding iron chelators to the culture after bacterial growth, in the presence of an organic iron source. We have investigated aspects concerning full expression of the meningococcal IRPs during normal growth, in defined conditions using Catlin medium, Mueller Hinton and Tryptic Soy Broth (TSB). The expression of IRPs varied between different strains with respect to Ethylenediamine Di-ortho-Hidroxy-phenyl-acetic acid (EDDA) concentrations, and according to culture medium, and also between different lots of TSB. For each strain, a specific set of IRPs were expressed and higher EDDA concentrations, or addition of glucose, or use of different culture media did not resulted in a differential expression of IRPs. We were not able to grow N. meningitidis under normal growth conditions using Desferal. We looked for a good yield of outer membrane vesicles (OMVs) expressing IRPs in iron-deficient Catlin medium containing EDDA and Hemin. Culture for 32 h at 30 degrees C after growing for 16 h at 37 degrees C supported good bacterial growth. Bacterial lysis was noted after additional 24 h at 30 degrees C. Approximately 4 times more OMVs was recoverable from a culture supernatant after 24 h at 30 degrees C than from the cells after 16 h at 37 degrees C. The IRP were as well expressed in OMVs from culture supernatant obtained after 24 h at 30 degrees C as from the cells after 16 h at 37 degrees C.

[Isolation of Haemophilus aegyptius associated with Brazilian purpuric fever, of Chloropidae (Diptera) of the genera Hippelates and Liohippelates]. / Isolamento de Haemophilus aegyptius associado à febre purpúrica brasileira, de cloropídeos (Diptera) dos gêneros Hippelates e Liohippelates.

The recognition of the Brazilian purpuric fever (BPF) in 1984 led to a number of studies which showed a relation between this disease and conjunctivitis caused by Haemophilus aegyptius. The increase in cases of conjunctivitis in children associated with higher population density of eye gnats (Chloropidae: Hippelates) has been reported since last century. This phenomenon is related to the attraction that those flies show for the eyes, secretions and wounds, from where they feed on. Although there are evidences on the role of these flies in the mechanical transmission of seasonal bacterial conjunctivitis, the isolation of Haemophilus aegyptius from them in their natural habitat had not been demonstrated yet. In this study Haemophilus aegyptius associated to BPF was isolated from two pools of chloropids collected around the eyes of children with conjunctivitis which were identified as Liohippelates peruanus (Becker) and a new species Hippelates neoproboscideus.

Isolamento de Haemophilus aegyptius associado a febre purpurica brasileira de cloropideos (diptera) dos generos Hippelates e Lioheppelates / Isolation of Haemophilus aegyptius associated to brazilian purpuric fever from Hippelates and Liohippelates flies (Diptera: Chloropidae)

O reconhecimento da Febre Purpurica Brasileira (FPB), em 1984, originou uma serie de estudos que revelaram uma correlacao desta doenca com conjuntivites causadas por Haemophilus aegyptius. A associacao do aumento de conjuntivites em criancas e a maior densidade populacional de cloropideos do genero Hippelates ja havia sido verificada desde o seculo passado. Este fenomeno esta relacionado ao tropismo que estes insetos apresentam pelos olhos, secrecoes e feridas de onde se alimentam....

[Brazilian purpuric fever, virulence in an animal model of Haemophilus aegyptius (H. influenzae biogroup aegyptius). Grupo de Estudo da Febre Purpúrica Brasileira]. / Febre purpúrica brasileira, virulência em modelo animal do Haemophilus aegyptius (H. influenzae biogrupo aegyptius).

Brazilian purpuric fever (BPF) is caused by invasive strains of Haemophilus aegyptius (H. influenzae biogroup aegyptius, Hae). These strains were differentiated from Hae strains associated only with conjunctivitis (non-invasive Hae strains) through specific molecular markers. Complement-depleted infant rat model was used to study the invasive and non-invasive Hae strains to compare their virulence potential. Inoculating 10(5) bacteria in the rats, the invasive strains caused 80 to 100% bacteremia and the intensity of bacteremia was 10(2.5 +/- 0.49) to > 10(4.69) cfu/ml of blood. Using the same infectious dose, the non-invasive strains did not cause frequent bacteremia (0 to 50%) and the intensity was 0 to 10(3.69 +/- 0.53) cfu/ml of blood. The infectious doses able to cause 50% of bacteremia in the rats (BD 50%) varied from < 10(3) to 10(4.2) bacteria for the invasive strains, whereas the BD 50% were 10(6.2) to > 10(7.3) bacteria for non-invasive strains. Passive immunization using antisera to invasive strains protected rats against bacteremia caused by homologous strains, but not by heterologous strain. By comparing the bacteremia caused by Hae and bacteremia caused by H. influenzae b (Eagan strain, Hib), it was demonstrated that Hib had higher virulence potential. This animal model was useful to clarify the virulence potential of invasive Hae strains.

Febre purpúrica brasileira. Caracterizaçäo rápida das cepas invasoras de Haemophilus aegyptius / Brazilian purpuric fever. Fast characterization of invasive strains of Haemophilus aegyptius

Cepas de H. aegyptus isoladas em surtos de Febre Purpúrica Brasileira (FPB) no Brasil, foram caracterizadas pelo método de aglutinaçäo em lâmina utilizando um anti-soro produzido com cepa de H. aegyptius isolada de cultura de sangue de paciente com FPB. Através desse método foi possível identificar cepas de H. aegyptius responsáveis por surtos de conjuntivite com características antigênicas iguais às cepas isoladas de FPB. A sensibilidade e especificidade da soroaglutinaçäo em lâmina foi de 97,7% e 89,6% respectivamente, podendo ser utilizado como método de triagem em estudos de conjuntivites purulentas, para detectar cepas invasivas de H. aegyptius associada a FPB, possibilitando assim a implantaçäo de medias que ampliem a eficiência na prevençäo e na vigilância epidemiológica da doença

[Brazilian purpuric fever. Fast characterization of invasive strains of Haemophilus aegyptius]. / Febre purpúrica brasileira. Caracterização rápida das cepas invasoras de Haemophilus aegyptius.

Strains of H. aegyptius isolated during outbreak of Brazilian Purpuric Fever (BPF) in Brazil were characterized antigenically by slide agglutination test utilizing antiserum produced with a H. aegyptius strain isolated from blood culture from a patient with BPF. By means of this method, it were identified H. aegyptius strains responsible for outbreaks of conjunctivitis with identical antigenic characteristics to strains isolated from BPF. The sensitivity and specificity of slide seroagglutination test was 97.7% and 89.6% respectively; therefore this assay was efficient to be used as a screening method in the studies of purulent conjunctivitis for detecting high risk populations for BPF, and to implement measures that will increase the efficiency of epidemiologic surveillance.