Top PDF MICROBIOLOGICAL CHARACTERISATION OF Haemophilus influenzae STRAINS ISOLATED FROM PATIENTS WITH INVASIVE AND RESPIRATORY DISEASES

MICROBIOLOGICAL CHARACTERISATION OF Haemophilus influenzae STRAINS ISOLATED FROM PATIENTS WITH INVASIVE AND RESPIRATORY DISEASES

MICROBIOLOGICAL CHARACTERISATION OF Haemophilus influenzae STRAINS ISOLATED FROM PATIENTS WITH INVASIVE AND RESPIRATORY DISEASES

A total of 175 H. influenzae strains were collected between 1994 and 2009 from all aged patient groups. The strains were isolated from patients with invasive and community-acquired respiratory tract infections. All strains were identified according to standard microbiological methods. Serotyping was done by a coagglutination test and by molecular PCR capsular genotyping. Beta-lactamase production was determined by the chromogenic cephalosporin test with nitrocephin as substrate.
Mostrar mais

4 Ler mais

Ribotyping, Biotyping and Capsular Typing of Haemophilus influenzae Strains Isolated from Patients in Campinas, Southeast Brazil

Ribotyping, Biotyping and Capsular Typing of Haemophilus influenzae Strains Isolated from Patients in Campinas, Southeast Brazil

Haemophilus influenzae, a commensal pleomorphic Gram- negative bacillus found in the human upper respiratory tract, has been associated with localized and invasive infections, such as bronchitis, otitis, pneumonia, meningitis, septicemia, and epiglottitis [1]. Systemic diseases are normally caused by Haemophilus influenzae serotype b (Hib) strains. The isolates obtained from infectious processes of the respiratory tract and from healthy individuals are usually unencapsulated and nontypable (NTHI) [2]. The current classification of this species is based on biotypes and capsular serotypes, which are subject to phenotypic variations and do not provide any clonal origin data [3]. Other typing methods, such as outer membrane protein analysis, lipopolysaccharide profiling, and multilocus enzyme electrophoresis, have been used to study the epidemiology and pathogenesis of H. influenzae infections [4]. Recently, H. influenzae strains have also been genomically characterized by determination of capsular types based on biomolecular techniques, including PCR-ribotyping [5], RAPD-PCR [6], PFGE [4], and PCR [7,8], all of which have revealed a great variety of patterns.
Mostrar mais

8 Ler mais

Potential pathogenic role of aggregative- adhering Corynebacterium diphtheriae of different clonal groups in endocarditis

Potential pathogenic role of aggregative- adhering Corynebacterium diphtheriae of different clonal groups in endocarditis

Invasive diseases caused by Corynebacterium diphtheriae have been described increasingly. Several reports indicate the destructive feature of endocarditis attributable to nontoxigenic strains. However, few reports have dealt with the pathogenicity of invasive strains. The present investigation demonstrates a phenotypic trait that may be used to identify potentially invasive strains. The study also draws attention to clinical and microbiological aspects observed in 5 cases of endocarditis due to C. diphtheriae that occurred outside Europe. Four cases occurred in female school-age children (7-14 years) treated at different hospitals in Rio de Janeiro, Brazil. All patients developed other complications including septicemia, renal failure and/or arthritis. Surgical treatment was performed on 2 patients for valve replacement. Lethality was observed in 40% of the cases. Microorganisms isolated from 5 blood samples and identified as C. diphtheriae subsp mitis (N = 4) and C. diphtheriae subsp gravis (N = 1) displayed an aggregative adherence pattern to HEp-2 cells and identical one-dimensional SDS-PAGE protein profiles. Aggregative-adhering invasive strains of C. diphtheriae showed 5 distinct RAPD profiles. Despite the clonal diversity, all 5 C. diphtheriae invasive isolates seemed to display special bacterial adhesive properties that may favor blood-barrier disruption and systemic dissemination of bacteria. In conclusion, blood isolates from patients with endocarditis exhibited a unique adhering pattern, suggesting a pathogenic role of aggregative-adhering C. diphtheriae of different clones in endocarditis. Accordingly, the aggregative-adherence pattern may be used as an indication of some invasive potential of C. diphtheriae strains.
Mostrar mais

6 Ler mais

Haemophilus influenzae strains: results of a Brazilian study carried out from 1996 through 2000

Haemophilus influenzae strains: results of a Brazilian study carried out from 1996 through 2000

The study included bacterial strains sent by the network of Central Public Health Laboratories located in several Brazilian states to the National Meningitis Reference Center, Adolfo Lutz Institute, Central Public Health Laboratory, São Paulo, SP, Brazil. The strains were isolated from patients ad- mitted to the public hospital network and were submitted to routine microbiological analysis. The strains were from the follow- ing states: Bahia (N = 324), Pernambuco (N = 313), Ceará (N = 10), Distrito Federal (N = 268), Goiás (N = 19), São Paulo (N = 557), Minas Gerais (N = 31), Paraná (N = 119), Santa Catarina (N = 45), and Rio Gran- de do Sul (N = 26). All strains were isolated from patients with invasive disease. The per- cent of children up to 5 years old enrolled in this study was 75%.
Mostrar mais

8 Ler mais

Meningite por Haemophilus influenzae tipo f.

Meningite por Haemophilus influenzae tipo f.

Com o declínio da taxa de infecções causadas pelo Haemophilus influenzae tipo b após a ampla introdução da vacina, sorotipos não-b devem ser considerados agentes patogênicos potenciais em crianças menores de 5 anos com doença invasiva. Relatamos um caso de meningite por Haemophilus influenzae tipo f em um lactente imunocompetente de 1 ano. O agente foi identificado em líquido cefalorraquidiano e hemocultura. A sorotipagem foi realizada por testes com soros policlonais e confirmada por reação em cadeia de polimerase. Todas as cepas de Haemophilus influenzae associadas à doença invasiva deveriam ser sorotipadas e notificadas, a fim de possibilitar uma análise adequada das mudanças e tendências na distribuição de sorotipos desta doença.
Mostrar mais

3 Ler mais

RESULTS Presence of the siderophore system in enteroinvasive

RESULTS Presence of the siderophore system in enteroinvasive

In the present article, some aspects of iron uptake systems exhibited by a collection of EIEC strains belonging to 10 different serotypes were analyzed. High affinity iron uptake systems were expressed by EIEC strains under iron-limiting growth conditions. All 30 strains studied for siderophore produced the phenolic siderophore enterobactin, and 12 produced in addition the hydroxamic siderophore aerobactin. The analysis of the outer membrane proteins expressed under iron starvation allowed us to divide the EIEC strains in five electrophoretic profiles, as shown in Table 1. Contrary to what it found for the ability of EIEC to use iron compounds (8), the pattern of expression of IROMPs is serotype-specific. We investigated the regulation of expression of the major IROMP by growing the cells in iron-replete medium and iron- limited medium, separating their outer membranes and subjecting them to SDS-PAGE. Earlier report has been shown variations in IROMPs expression due the chelators used to restrict the availability of iron (6). It has been shown that E.coli O164 did not produce 81 kDa IROMP, when it is growing in TSB medium containing α-α’dipyridyl, but expressed 83 kDa, 81 kDa, 78 kDa, 76 kDa and 74 kDa IROMPs under EDDA or desferral as iron chelators (6). However, our observations showed that strains of E.coli O164 express 82 kDa and 76 kDa IROMPs under LB medium with α-α’dipyridyl chelator. This results lead us to suggest that expression of IROMPs is also medium dependent.
Mostrar mais

6 Ler mais

Protease activity in Giardia duodenalis trophozoites of axenic strains isolated from symptomatic and asymptomatic patients

Protease activity in Giardia duodenalis trophozoites of axenic strains isolated from symptomatic and asymptomatic patients

trophozoites (Hare et al. 1989, Parenti 1991), recent stud- ies have demonstrated multiple proteases in the parasite (Robertson et al. 1991, Williams & Coombs 1995, Jimenez et al. 2000). Our results corroborate latter findings, since we detected five bands in the trophozoite lysate of BTU- 10 strain, and 10-11 bands in the lysates of BTU-11 and P1 strains. Some of the main proteases detected showed molecular masses similar to those demonstrated previ- ously. In the analysis of strain P1, Williams and Coombs (1995) detected as the proteases producing the most pro- nounced hydrolysis zones those with molecular masses of 120 kDa, 80 kDa, 73 kDa, 66 kDa, 57 kDa, 33 kDa and 31 kDa. More recently, Jimenez et al. (2000) identified pro- teolytic bands at 16, 20, 66, 82, 108 and 120 kDa in the lysate of P1 strain. Employing the same strain, we distin- guished the bands with molecular masses of 116 kDa, 92- 78 kDa (bands 2-4), 64 kDa, 58 kDa, 50 kDa and a group of diffuse bands in the region of 32-23 kDa. The Brazilian strains lysates revealed bands of hydrolysis with similar molecular masses. Another important finding was the de- tection in all strains of a band with an approximate mo- lecular mass of 50 kDa. Moreover, this band was the most pronounced zone of hydrolysis in the profiles of strains BTU-11 and P1, isolated from symptomatic cases. We may wonder whether this protease is an important component in the strains obtained from symptomatic patients. To confirm this possibility, the purification and characteriza- tion of the enzyme may be warranted.
Mostrar mais

5 Ler mais

J. Pediatr. (Rio J.)  vol.85 número5 en v85n5a09

J. Pediatr. (Rio J.) vol.85 número5 en v85n5a09

(counts and describes) laboratory characteristics, such as serotype and in vitro resistance pattern of the strains collected. Since April 1999, Uberlândia, Brazil, has been participating in the national network of the SIREVA Project by sending pneumococcal strains isolated at the clinical analysis lab of Hospital de Clínicas of Universidade Federal de Uberlândia (HC-UFU), Uberlândia, to Instituto Adolfo Lutz (IAL), São Paulo, Brazil.

5 Ler mais

Restriction fragment length polymorphism (RFLP) analysis and tuberculosis epidemiology

Restriction fragment length polymorphism (RFLP) analysis and tuberculosis epidemiology

bacterium tuberculosis strains isolated from Colombian patients, together with resistance to antituberculous medications in the Department of Quindio, Colombia, a prospec[r]

11 Ler mais

Pattern of functional antibody activity against Haemophilus influenzae type b (Hib) in infants immunized with diphtheria- tetanus-pertussisHib Brazilian combination vaccine

Pattern of functional antibody activity against Haemophilus influenzae type b (Hib) in infants immunized with diphtheria- tetanus-pertussisHib Brazilian combination vaccine

When we assessed the subclasses of IgG we observed that the vaccinees responded with IgG anti-PRP of both IgG1 and IgG2 subclasses, but with a significant predomi- nance of anti-PRP IgG1. We observed a good relationship between IgG and IgG1 antibody levels, but no correlation was found with IgG2 levels. Our results agree with those obtained with different PRP conjugates by Granoff et al. (27), who also reported that infants immunized with PRP-OMP respond predominantly with anti-PRP IgG1, while adults immunized with unconjugated PRP or PRP-D respond with anti-PRP of both IgG1 and IgG2 subclasses, as is the case for the DTP-Hib vaccine. Hetherington et al. (28) have also suggested that the IgG subclass response to PRP protein conjugate is age independent. Other investigators have also reported that IgG1 antibodies are more effective than IgG2 antibodies for Hib in an opsonization test and in activating complement-mediated bacteriolysis (29-32).
Mostrar mais

7 Ler mais

J. Bras. Patol. Med. Lab.  vol.42 número1

J. Bras. Patol. Med. Lab. vol.42 número1

control the dissemination of salmonellosis is to employ molecular techniques. Methods based on DNA restriction analysis, such as ribotyping, can discriminate Salmonella strains involved in human infection and give information on the epidemiological and genetic relationship among serotypes. Hence, to differentiate serotypes such as S. Enteritidis, ribotyping has been employed in epidemiological investigation all over the world (2, 9, 10) .

5 Ler mais

Screening and kinetics of glutaminase and glutamate decarboxylase producing lactic acid bacteria from fermented Thai foods

Screening and kinetics of glutaminase and glutamate decarboxylase producing lactic acid bacteria from fermented Thai foods

Glutaminase distributed in all the microbes like bacteria, yeast and fungi, and they were reported to produce notable amount of glutaminase (Nandakumar et al., 2003). This enzyme widely used in food industries for the enzymatic degradation of proteins, which present in the raw materials. More specifically, flavor of the fermented soy sauce is due to glutamic acid produced by glutaminase. There are many numbers of glutaminase reported from different microbial sources with a wide range of fermentation conditions as summarized by Nandakumar  et  al. (2003). More specifically, they differ in molecular weight, optimum pH and substrate specificity. Several glutaminases were reported to have both an optimal and stable temperature of ~ 40-50 ºC. Some previous studies have reported about the temperature stability and activity of several glutaminases (Prusiner  et  al., 1976; Moriguchi  et  al., 1994; Koibuchi et al., 2000). Glutaminases from Aspergillus oryzae, Micrococcus luteus K-3 and Bacillus subtilis are known for its high-salt tolerance capacity (Yano et al., 1988; Moriguchi et al., 1994; Madern et al., 2000; Kennedy et al., 2001).
Mostrar mais

11 Ler mais

J. Pediatr. (Rio J.)  vol.80 número1 en v80n1a09

J. Pediatr. (Rio J.) vol.80 número1 en v80n1a09

On the other hand, the comparison of the results of the present study with those obtained from Brazilian studies shows some discrepancy. The results varied from negative culture findings in all samples to 33.4% of positive findings. Among the predominant pathogens, in addition to H. influenzae, S. pneumoniae and M. catarrhalis (not necessarily in this order), S. aureus, S. epidermidis and P. aeruginosa also were highly prevalent. 13-15 Very likely, the different inclusion criteria, microbiological methodology, geographical variations, and variability influenced by the small sample size are the cause for the discrepancies observed in the comparison of the results of these studies between themselves and with the present study.
Mostrar mais

8 Ler mais

Invasive Haemophilus influenzae disease in the vaccine era in Rio de Janeiro, Brazil

Invasive Haemophilus influenzae disease in the vaccine era in Rio de Janeiro, Brazil

We present here for the first time the results of geno- typing and cap locus characterisation of a collection of Hi isolates from Brazil, which revealed a genetically diverse population of encapsulated and non-encapsulated isolates causing invasive disease after the introduction of the con- jugate vaccine. We demonstrated that Hia and Hib isolates belonged to two distinct clonal complexes, cc23 and cc6, respectively. In both clonal complexes, new STs were iden- tified, which is consistent with an evolved population. ST- 23 lineage has frequently been associated with serotype a in different countries, and belongs to a cluster of related STs (Meats et al. 2003, Ulanova & Tsang 2014). ST-23 and unrelated ST-4 serotype a have been described as those causing meningitis in Brazil (Lima et al. 2010). ST-6 repre- sents the major clonal group of serotype b recovered from patients with invasive disease (Meats et al. 2003). MLST of Brazilian Hib has not been previously published. We identified only three spontaneously occurring capsular deficient mutants of Hib (b - ), all belonging to cc6. These
Mostrar mais

7 Ler mais

The evaluation of staphylococci strains isolated from nasal and bone cultures in patients with chronic osteomyelitis

The evaluation of staphylococci strains isolated from nasal and bone cultures in patients with chronic osteomyelitis

Materials and methods: Bone and nasal cultures were performed intra-operative and pre-operatively from 43 patients with chronic osteomyelitis. Inoculation was per- formed on 5% sheep blood and eosine-methylen-blue agar. The samples were incubated at 37°C for 24 hours. Catalase and coagulase tests were performed on Gram positive coccus strains. Antimicrobial susceptibilities of all S. aureus strains were evaluated by disc diffusion method according to CLSI for oxacillin and other antibiotics. Results: In this study pre-operative nasal cultures and intra-operative bone cultures obtained between May 2005 and September 2006 were evaluated retrospectively. Of the 43 nasal cultures, 31 (72%) yielded staphylococcal strain, of these 18 (58%) were S. aureus. Of the 18 S. aureus strains, 13 (72.2%) have methicilline resistance. On the other hand, of the 43 bone cultures, 29 (67.4%) yielded staphylococci strain, of these 23 (79.3%) were S. aureus. Of the 23 S. aureus strains, 52.1% have methicil- line resistance. Overall the similarity rate of staphylococ- cal strains was 38% (11/29), while considering the status of strains resistant to antibiotics; this ratio was 24% (7/29). Conclusions: Nasal S. aureus carriage rate (58%) in pa- tients with chronic osteomyelitis was higher than the com- munity and the other patient groups. However, the surveil- lance cultures can give knowledge about the causative pathogen of 25% of the culture negative cases.
Mostrar mais

5 Ler mais

Dissertação para obtenção do Grau de Mestre em Bioquímica Orientador: Maria Paula Bajanca Lavado, Investigadora auxiliar, Instituto Nacional de Saúde Doutor Ricardo Jorge Co-orientador: Maria Luísa Forte Marques Jordão, Investigadora auxiliar, Instituto N

Dissertação para obtenção do Grau de Mestre em Bioquímica Orientador: Maria Paula Bajanca Lavado, Investigadora auxiliar, Instituto Nacional de Saúde Doutor Ricardo Jorge Co-orientador: Maria Luísa Forte Marques Jordão, Investigadora auxiliar, Instituto N

with relevant worldwide information regarding AOM and CSOM. From the information they gathered, the authors observed that the global AOM incidence rate is estimated as 709 million cases per year, with 51% of the cases being registered in children under the age of five. In Central Europe, 40% of the cases occurred in children with ages ranging from less than one to five years old. CSOM, on the other hand, registered 31 million cases each year, with 22.6% of these cases occurring in children under the age of five years old. As for mortality rates, the authors estimated that approximately 21,000 people die, each year, due to complications related with OM. The authors stated that, although the mortality rates associated with OM are relatively low, when considering the overall combination of AOM and CSOM, plus respective sequels, the numbers should be considered relevant, more specifically in the first five years of life. 43
Mostrar mais

99 Ler mais

The microbiological and clinical characteristics of invasive salmonella in gallbladders from cholecystectomy patients in kathmandu, Nepal.

The microbiological and clinical characteristics of invasive salmonella in gallbladders from cholecystectomy patients in kathmandu, Nepal.

Patients were routinely examined by ultrasonography before surgery to assess the presence of gallstones and to detect inflammation. The surgeon performing the procedure curated a report, assessing the thickness of the gallbladder wall (stratified into three categories, thick: .4 mm, normal: 4 mm and thin: ,4 mm), the presence and the number of gallstones, the presence and characteristics of fluid (pus: empyema, mucoid/clear/watery: mucocele and sludge) and overall morphology (contracted or distended). Hematocrit, total leukocytes with differential count, total bilirubin, conjugated bilirubin, alanine aminotransferase (ALT), aspartate aminotransferase (AST), and amylase were measured prior to surgical intervention. All extracted tissue was subjected to a histopathological examination to assess/confirm the extent of the inflammation; all histopathology was performed by the same skilled technician who was blinded to presence or absence of bacteria within the bile. All sections we examined by light microscopy after staining with heamatoxylin and eosin. Inflammation was identified by tissue morphology and the presence of neutrophils (acute) and lymphocytes (chronic).
Mostrar mais

7 Ler mais

Characterization of Trypanosoma cruzi Strains Isolated from Chronic Chagasic Patients, Triatomines and Opossums Naturally Infected from the State of Rio Grande do Sul, Brazil

Characterization of Trypanosoma cruzi Strains Isolated from Chronic Chagasic Patients, Triatomines and Opossums Naturally Infected from the State of Rio Grande do Sul, Brazil

analysis of T. cruzi strains belonging to distinct zymodemes showed a close correlation between the major groups defined by RAPD and zymodemes (Steindel et al. 1993, Tibayrenc et al. 1993). We obtained similar results when T. cruzi Z1, Z2 and ZB strains were compared using primer 3303. In the present study a comparison of the RAPD profiles of 2 Z1 strains generated with 2 primers showed that 74% of the bands were shared. A more extensive analysis of T. cruzi Z1 from a wide geographical distribution showed that an av- erage of 55% of the RAPD bands were shared be- tween the strains (Steindel et al. 1993). Using a single primer and a more limited number of strains the authors found that the percentage of bands shared within zymodeme was 73.6% for Z2 and 70.1% for ZB. In the present study, where a more significant number of strains from zymodemes Z2 and ZB, were compared using primers 3307, λgt11R and λgt11F a higher intrazymodeme ge- netic heterogeneity was evidenced. Using primer λgt11F the percentage of RAPD bands shared within 13 ZB and 13 Z2 strains was respectively 43.3% and 33.3%. However, when 3 primers were used, the bands shared decreased to 20% for ZB and 14% for Z2. The heterogeneity found in our T. cruzi ZB and Z2 strains from chronic patients shows that these parasite populations are more polymorphic and demonstrates the analytical power of RAPD. It remains to be observed if there is a relationship between the high genetic heterogene- ity of T. cruzi strains and different clinical forms of human Chagas’ disease in Rio Grande do Sul.
Mostrar mais

10 Ler mais

Molecular characterization of adenoviruses from children presenting with acute respiratory disease in Uberlândia, Minas Gerais, Brazil, and detection of an isolate genetically related to feline adenovirus

Molecular characterization of adenoviruses from children presenting with acute respiratory disease in Uberlândia, Minas Gerais, Brazil, and detection of an isolate genetically related to feline adenovirus

Of the total 33 HAdV positive specimens, 31 NPAs were tested using the characterization PCR assay (2 of the samples lacked enough material to be tested). Ten of these samples tested positive and were subsequently sequenced. The remaining 21 samples were inoculated into cell culture (A-549) and their DNA was extracted from cell scrapes. From these, six additional PCR-posi- tive samples were obtained. However, due to the insuf- ficient amount of PCR products, only three of them were sequenced, providing a total of 13 sequenced samples. Some factors may have contributed to the limited num- ber of specimens that tested positive using the PCR method described by Allard et al. (2001). NPAs were collected within five days after the onset of symptoms and it is possible that some of the specimens collected on the 5th day contained a low number of infected cells and/ or had a low virus titre. In addition, we used freshly col- lected cells in the IF assay and stored specimens for PCR and inoculation of cell culture. Moreover, detection PCR was performed in two rounds (nested PCR), while char- acterization PCR was carried out in one round. Lastly, the use of fresh samples would probably help to increase the number of positive specimens for characterization, but performing the test daily would be impractical and cumbersome. Identification of the nucleotide sequences from a highly conserved region among various sero- types that allow for characterization for the development of a two-round PCR assay would increase the sensitivity of detection and allow for the characterization of more specimens. However, this task is very difficult and is a subject for another study.
Mostrar mais

5 Ler mais

Situação epidemiológica das meningites por haemophilus influenzae b na Direção Regional de Piracicaba - São Paulo.

Situação epidemiológica das meningites por haemophilus influenzae b na Direção Regional de Piracicaba - São Paulo.

No que diz respeito às meningites causadas especifica- mente pelo Haemophilus influenzae b, verificou-se maior incidência da enfermidade e maior número de óbitos em 1994, e queda importante em 1995, 2000 e 2001, sendo que a redução nesses dois últimos anos parece ser em de- corrência da introdução da vacina em 1999. A maior parte dos casos ocorreu no grupo de menores de 1 ano e os acha- dos relativos aos sinais e sintomas se assemelham às me- ningites por todas as etiologias. Compatibilidade nos acha- dos também pode ser observada em relação à zona e mu- nicípio de residência, notificação e de internação dos ca- sos. Por fim, verificou-se a redução dos casos de meningite por Haemophilus influenzae b com a introdução da vacina em 1999.
Mostrar mais

7 Ler mais

Show all 10000 documents...

temas relacionados