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1.
Front Microbiol ; 11: 1176, 2020.
Article in English | MEDLINE | ID: mdl-32655514

ABSTRACT

Acinetobacter baumannii is an opportunistic bacterial pathogen infecting immunocompromised patients and has gained attention worldwide due to its increased antimicrobial resistance. Here, we report a comparative whole-genome sequencing and analysis coupled with an assessment of antibiotic resistance of 46 Acinetobacter strains (45 A. baumannii plus one Acinetobacter nosocomialis) originated from five hospitals from the city of Recife, Brazil, between 2010 and 2014. An average of 3,809 genes were identified per genome, although only 2,006 genes were single copy orthologs or core genes conserved across all sequenced strains, with an average of 42 new genes found per strain. We evaluated genetic distance through a phylogenetic analysis and MLST as well as the presence of antibiotic resistance genes, virulence markers and mobile genetic elements (MGE). The phylogenetic analysis recovered distinct monophyletic A. baumannii groups corresponding to five known (ST1, ST15, ST25, ST79, and ST113) and one novel ST (ST881, related to ST1). A large number of ST specific genes were found, with the ST79 strains having the largest number of genes in common that were missing from the other STs. Multiple genes associated with resistance to ß-lactams, aminoglycosides and other antibiotics were found. Some of those were clearly mapped to defined MGEs and an analysis of those revealed known elements as well as a novel Tn7-Tn3 transposon with a clear ST specific distribution. An association of selected resistance/virulence markers with specific STs was indeed observed, as well as the recent spread of the OXA-253 carbapenemase encoding gene. Virulence genes associated with the synthesis of the capsular antigens were noticeably more variable in the ST113 and ST79 strains. Indeed, several resistance and virulence genes were common to the ST79 and ST113 strains only, despite a greater genetic distance between them, suggesting common means of genetic exchange. Our comparative analysis reveals the spread of multiple STs and the genomic plasticity of A. baumannii from different hospitals in a single metropolitan area. It also highlights differences in the spread of resistance markers and other MGEs between the investigated STs, impacting on the monitoring and treatment of Acinetobacter in the ongoing and future outbreaks.

2.
Braz. j. microbiol ; 39(2): 238-240, Apr.-June 2008. tab
Article in English | LILACS | ID: lil-487697

ABSTRACT

The aim of the present study was to evaluate qualitative changes in the glycoconjugate expression in human gastric tissue of positive and negative patients for Helicobacter pylori, through lectins: Wheat Germ Agglutinin (WGA) and Concanavalin A (Con A). The lectins recognized differently the glycoconjugates in the superficial mucous layer at the gastric tissues. The results suggest a significant change in the carbohydrate moieties present on the surface of the gastric cells during infection.


O objetivo do presente estudo foi avaliar as mudanças qualitativas na expressão de glicoconjugados em tecidos gástrico humano de pacientes infectados ou não pelo Helicobacter pylori, através das lectinas: Wheat germ agglutinin (WGA) e Concanavalina A (Con A). As lectinas reconheceram diferentemente os glicoconjugados nas camadas mucosas superficiais do tecido gástrico. Os resultados sugerem mudanças significantes nas porções de carboidratos presentes nas células gástricas durante a infecção.


Subject(s)
Humans , Gastric Mucosa , Glycoconjugates , Helicobacter Infections , Helicobacter pylori/isolation & purification , In Vitro Techniques , Lectins/isolation & purification , Methods
3.
Braz J Microbiol ; 39(2): 238-40, 2008 Apr.
Article in English | MEDLINE | ID: mdl-24031208

ABSTRACT

The aim of the present study was to evaluate qualitative changes in the glycoconjugate expression in human gastric tissue of positive and negative patients for Helicobacter pylori, through lectins: Wheat Germ Agglutinin (WGA) and Concanavalin A (Con A). The lectins recognized differently the glycoconjugates in the superficial mucous layer at the gastric tissues. The results suggest a significant change in the carbohydrate moieties present on the surface of the gastric cells during infection.

4.
Biotechnol Bioeng ; 97(1): 182-7, 2007 May 01.
Article in English | MEDLINE | ID: mdl-17013937

ABSTRACT

The S100 proteins have been extensively used as cancer biomarkers. The objectives of the present work were to immobilize the antibody anti-protein S100 to a net of semi-interpenetrated of polysiloxane and polyvinyl alcohol (POS-PVA discs), to investigate its capacity to capture S100 protein from serum and to quantify it by ELISA in sera from patients with prostatic adenocarcinoma (n = 15) and healthy individuals (n = 10). Also these values were compared to the S100 protein expression in the prostatic tissue through immunohistochemistry. The POS-PVA discs fixed about 92.8% of the offered antibody (7.75 microg of antibody per disc). The best values of the immobilized no-marked antibody anti-S100 and serum dilution were found to be 10 microg and 1:400, respectively. Optical density (OD) values for the sera of patients (0.425 +/- 0.042) with prostatic adenocarcinoma were significantly lower (P < 0.05) compared to those established for the healthy individuals (1.034 +/- 0.124). In the immunohistochemistry study no significant variations were observed in the number of positive S100 cells between prostatic adenocarcinoma (153.45 +/- 16.82) and normal prostate (147.04 +/- 18.98). These results showed a clear difference between S100 proteins expressed in tissue and presented in serum during the prostatic tissue neoplasic transformation. Sera analysis was more sensitive than immunohistochemistry S100 protein detection in the prostate tissue besides the advantage to be less invasive method.


Subject(s)
Biomarkers, Tumor/blood , Enzyme-Linked Immunosorbent Assay/methods , Neoplasm Proteins/blood , Prostatic Neoplasms/blood , Prostatic Neoplasms/diagnosis , S100 Proteins/blood , Biomarkers, Tumor/immunology , Humans , Male , Neoplasm Proteins/immunology , Prostatic Neoplasms/immunology , Reproducibility of Results , S100 Proteins/immunology , Sensitivity and Specificity
5.
An. Fac. Med. Univ. Fed. Pernamb ; 44(1): 21-25, 1999. tab
Article in Portuguese | LILACS | ID: lil-243025

ABSTRACT

Com o objetivo da avaliar a repercussão da esquistossomose mansônica sobre as células caliciformes do intestino delgado de camudongos, estudaram-se, através da histoquímica e morfometria, 48 animais (40 infectados com cercárias de S. mansoni, cepa SLM, e oito controles). O tempo de evolução da infecção variou de 40 a 75 dias. Para o estudo histólogico e histoquímico, cortes teciduais foram corados,respectivamente, com hematoxilina-eosina e alcian blue, pH2,5. As medidas morfométricas foram realizadas em um analisador de imagens, constituído por um microcomputador, com mesa digitalizadora, acoplado a um microscópio. O estudo histólogico mostrou alterações estruturais decorrentes principalmente da presença de granulomas periovulares, além da congestão, edema, e infiltrado inflamatório difuso. A histoquímica permitiu caracterizar as células caliciformes produtoras de mucina ácida. A morfometria evidênciou aumento estatisticamente significativo tanto de número dessas células como quantidade de mucina por vilosidade à medida que a infeção evoluiu. Essas alterações são provavelmente medidas por mecanismos imunológicos


Subject(s)
Animals , Mice , Disease Models, Animal , Intestines/physiopathology , Schistosomiasis mansoni , Enteroendocrine Cells
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