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1.
Braz J Microbiol ; 50(4): 943-952, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31432465

RESUMO

Brazilian data for maternal GBS colonization shows different prevalence rates. This conflicting data may be related to the absence of an official recommendation from the Federal Brazilian Health Authorities describing guidelines and protocols to perform GBS screening in pregnant women, in both public and private clinics. In the present review, we evaluated published reports addressing the prevalence of GBS in different regions of the country, methods used, and, when available, information regarding antibiotic resistance and serological typing of clinical isolates. According to this review, GBS prevalence in pregnant women in Brazil ranged from 4.2 to 28.4%, in the last 10 years. Serotype Ia was the most prevalent. The highest antibiotic resistance rates were found for tetarcycline, although its use to treat GBS infections is not common. Our results also show high resistance rates to clindamycin and erythromycin, which are commonly used as an alternative to penicillin in GBS infecctions. The increased antibiotic resistance, variations in serotype distribution, and high GBS prevalences need to be further investigated. Based on the present situation, recommendations regarding GBS surveillance in the country were raised and may improve our strategies for preventing neonatal infections.


Assuntos
Farmacorresistência Bacteriana , Complicações Infecciosas na Gravidez/microbiologia , Infecções Estreptocócicas/microbiologia , Streptococcus agalactiae/isolamento & purificação , Antibacterianos/farmacologia , Brasil/epidemiologia , Feminino , Humanos , Gravidez , Complicações Infecciosas na Gravidez/epidemiologia , Sorogrupo , Infecções Estreptocócicas/epidemiologia , Streptococcus agalactiae/classificação , Streptococcus agalactiae/efeitos dos fármacos , Streptococcus agalactiae/genética
2.
Rev. bras. psiquiatr ; 40(3): 256-263, July-Sept. 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-959240

RESUMO

Objective: There are few quantitative studies on art therapy for the treatment of depression. The objective of this study was to evaluate if art therapy is beneficial as an adjuvant treatment for depression in the elderly. Methods: A randomized, controlled, single-blind study was carried out in a sample of elderly women with major depressive disorder (MDD) stable on pharmacotherapy. The experimental group (EG) was assigned to 20 weekly art therapy sessions (90 min/session). The control group (CG) was not subjected to any adjuvant intervention. Patients were evaluated at baseline and after 20 weeks, using the Geriatric Depression Scale (GDS), Beck Depression Inventory (BDI), Beck Anxiety Inventory (BAI), and cognitive measures. Results: Logistic regression analysis adjusted for age revealed that women in EG (n=31) had significant improvement in GDS (p = 0.007), BDI (p = 0.025), and BAI (p = 0.032) scores as compared with controls (n=25). No difference was found in the cognitive measures. Conclusion: Art therapy as an adjunctive treatment for MDD in the elderly can improve depressive and anxiety symptoms. Clinical trial registration: RBR-2YXY7Z


Assuntos
Humanos , Feminino , Pessoa de Meia-Idade , Idoso , Arteterapia/normas , Avaliação Geriátrica , Transtorno Depressivo Maior/terapia , Transtornos de Ansiedade/terapia , Escalas de Graduação Psiquiátrica , Psicoterapia , Fatores Socioeconômicos , Fatores de Tempo , Método Simples-Cego , Resultado do Tratamento , Terapia Combinada , Testes Neuropsicológicos
3.
Braz J Psychiatry ; 40(3): 256-263, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29412335

RESUMO

OBJECTIVE: There are few quantitative studies on art therapy for the treatment of depression. The objective of this study was to evaluate if art therapy is beneficial as an adjuvant treatment for depression in the elderly. METHODS: A randomized, controlled, single-blind study was carried out in a sample of elderly women with major depressive disorder (MDD) stable on pharmacotherapy. The experimental group (EG) was assigned to 20 weekly art therapy sessions (90 min/session). The control group (CG) was not subjected to any adjuvant intervention. Patients were evaluated at baseline and after 20 weeks, using the Geriatric Depression Scale (GDS), Beck Depression Inventory (BDI), Beck Anxiety Inventory (BAI), and cognitive measures. RESULTS: Logistic regression analysis adjusted for age revealed that women in EG (n=31) had significant improvement in GDS (p = 0.007), BDI (p = 0.025), and BAI (p = 0.032) scores as compared with controls (n=25). No difference was found in the cognitive measures. CONCLUSION: Art therapy as an adjunctive treatment for MDD in the elderly can improve depressive and anxiety symptoms. CLINICAL TRIAL REGISTRATION: RBR-2YXY7Z.


Assuntos
Arteterapia/normas , Transtorno Depressivo Maior/terapia , Avaliação Geriátrica , Idoso , Transtornos de Ansiedade/terapia , Terapia Combinada , Feminino , Humanos , Pessoa de Meia-Idade , Testes Neuropsicológicos , Escalas de Graduação Psiquiátrica , Psicoterapia , Método Simples-Cego , Fatores Socioeconômicos , Fatores de Tempo , Resultado do Tratamento
4.
Infect Immun ; 84(4): 1112-1122, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26831466

RESUMO

The expression of flagella correlates with different aspects of bacterial pathogenicity, ranging from adherence to host cells to activation of inflammatory responses by the innate immune system. In the present study, we investigated the role of flagella in the adherence of an atypical enteropathogenic Escherichia coli (aEPEC) strain (serotype O51:H40) to human enterocytes. Accordingly, isogenic mutants deficient in flagellin (FliC), the flagellar structural subunit; the flagellar cap protein (FliD); or the MotAB proteins, involved in the control of flagellar motion, were generated and tested for binding to differentiated Caco-2 cells. Binding of the aEPEC strain to enterocytes was significantly impaired in strains with the fliCa nd fliD genes deleted, both of which could not form flagella on the bacterial surface. A nonmotile but flagellated MotAB mutant also showed impaired adhesion to Caco-2 cells. In accordance with these observations, adhesion of a EPEC strain 1711-4 to Caco-2 cells was drastically reduced after the treatment of Caco-2 cells with purified FliD. In addition, incubation of a EPEC bacteria with specific anti-FliD serum impaired binding to Caco-2 cells. Finally, incubation of Caco-2 cells with purified FliD, followed by immunolabeling, showed that the protein was specifically bound to the microvillus tips of differentiated Caco-2 cells. The a EPEC FliD or anti-FliD serum also reduced the adherence of prototype typical enteropathogenic, enterohemorrhagic, and enterotoxigenic E. coli strains to Caco-2 cells. In conclusion, our findings further strengthened the role of flagella in the adherence of a EPEC to human enterocytes and disclosed the relevant structural and functional involvement of FliD in the adhesion process.


Assuntos
Aderência Bacteriana/fisiologia , Proteínas de Bactérias/metabolismo , Enterócitos/microbiologia , Escherichia coli Enteropatogênica/fisiologia , Microvilosidades/fisiologia , Animais , Anticorpos , Proteínas de Bactérias/genética , Células CACO-2 , Enterócitos/fisiologia , Escherichia coli Enteropatogênica/genética , Humanos , Imuno-Histoquímica , Camundongos , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Mutação , Coelhos , Proteínas Recombinantes
5.
Infect Immun ; 82(12): 4978-88, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25225243

RESUMO

Streptococcus mutans is a major etiologic agent of dental caries, a prevalent worldwide infectious disease and a serious public health concern. The surface-localized S. mutans P1 adhesin contributes to tooth colonization and caries formation. P1 is a large (185-kDa) and complex multidomain protein considered a promising target antigen for anticaries vaccines. Previous observations showed that a recombinant P1 fragment (P1(39-512)), produced in Bacillus subtilis and encompassing a functional domain, induces antibodies that recognize the native protein and interfere with S. mutans adhesion in vitro. In the present study, we further investigated the immunological features of P1(39-512) in combination with the following different adjuvants after parenteral administration to mice: alum, a derivative of the heat-labile toxin (LT), and the phase 1 flagellin of S. Typhimurium LT2 (FliCi). Our results demonstrated that recombinant P1(39-512) preserves relevant conformational epitopes as well as salivary agglutinin (SAG)-binding activity. Coadministration of adjuvants enhanced anti-P1 serum antibody responses and affected both epitope specificity and immunoglobulin subclass switching. Importantly, P1(39-512)-specific antibodies raised in mice immunized with adjuvants showed significantly increased inhibition of S. mutans adhesion to SAG, with less of an effect on SAG-mediated bacterial aggregation, an innate defense mechanism. Oral colonization of mice by S. mutans was impaired in the presence of anti-P1(39-512) antibodies, particularly those raised in combination with adjuvants. In conclusion, our results confirm the utility of P1(39-512) as a potential candidate for the development of anticaries vaccines and as a tool for functional studies of S. mutans P1.


Assuntos
Adesinas Bacterianas/imunologia , Anticorpos Antibacterianos/imunologia , Cárie Dentária/prevenção & controle , Proteínas de Membrana/imunologia , Infecções Estreptocócicas/prevenção & controle , Vacinas Estreptocócicas/imunologia , Streptococcus mutans/imunologia , Adesinas Bacterianas/genética , Adjuvantes Imunológicos/administração & dosagem , Aglutininas/metabolismo , Animais , Anticorpos Antibacterianos/sangue , Bacillus subtilis/genética , Aderência Bacteriana , Cárie Dentária/imunologia , Feminino , Proteínas de Membrana/genética , Camundongos Endogâmicos BALB C , Boca/microbiologia , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Saliva/metabolismo , Infecções Estreptocócicas/imunologia , Vacinas Estreptocócicas/administração & dosagem , Vacinas Estreptocócicas/genética , Streptococcus mutans/genética , Vacinas Sintéticas/administração & dosagem , Vacinas Sintéticas/genética , Vacinas Sintéticas/imunologia
6.
Infect Immun ; 82(4): 1414-23, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24421038

RESUMO

Bacillus subtilis spores have been used as safe and heat-resistant antigen delivery vectors. Nonetheless, the oral administration of spores typically induces weak immune responses to the passenger antigens, which may be attributed to the fast transit through the gastrointestinal tract. To overcome this limitation, we have developed B. subtilis spores capable of binding to the gut epithelium by means of expressing bacterial adhesins on the spore surface. The resulting spores bound to in vitro intestinal cells, showed a longer transit through the mouse intestinal tract, and interacted with Peyer's patch cells. The adhesive spores increased the systemic and secreted antibody responses to the Streptococcus mutans P1 protein, used as a model antigen, following oral, intranasal, and sublingual administration. Additionally, P1-specific antibodies efficiently inhibited the adhesion of the oral pathogen Streptococcus mutans to abiotic surfaces. These results support the use of gut-colonizing B. subtilis spores as a new platform for the mucosal delivery of vaccine antigens.


Assuntos
Antígenos de Bactérias/administração & dosagem , Bacillus subtilis/imunologia , Vacinas Bacterianas/administração & dosagem , Mucosa Gástrica/imunologia , Esporos Bacterianos/imunologia , Adesinas Bacterianas/fisiologia , Administração Intranasal , Administração Oral , Animais , Anticorpos Antibacterianos/imunologia , Antígenos de Bactérias/imunologia , Aderência Bacteriana , Vacinas Bacterianas/imunologia , Western Blotting , Eletroforese em Gel de Poliacrilamida , Mucosa Gástrica/microbiologia , Imunidade nas Mucosas/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Modelos Animais
7.
F1000Res ; 3: 74, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25580222

RESUMO

Shiga toxin (Stx) is considered the main virulence factor in Shiga toxin-producing Escherichia coli (STEC) infections. Previously we reported the expression of biologically active Stx by eukaryotic cells in vitro and in vivo following transfection with plasmids encoding Stx under control of the native bacterial promoter (1,2). Since stx genes are present in the genome of lysogenic bacteriophages, here we evaluated the relevance of bacteriophages during STEC infection. We used the non-pathogenic E. coli C600 strain carrying a lysogenic 933W mutant bacteriophage in which the stx operon was replaced by a gene encoding the green fluorescent protein (GFP). Tracking GFP expression using an In Vivo Imaging System (IVIS), we detected fluorescence in liver, kidney, and intestine of mice infected with the recombinant E. coli strain after treatment with ciprofloxacin, which induces the lytic replication and release of bacteriophages. In addition, we showed that chitosan, a linear polysaccharide composed of d-glucosamine residues and with a number of commercial and biomedical uses, had strong anti-bacteriophage effects, as demonstrated at in vitro and in vivo conditions. These findings bring promising perspectives for the prevention and treatment of haemolytic uremic syndrome (HUS) cases.

8.
PLoS One ; 8(11): e80083, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24282519

RESUMO

BACKGROUND: The uptake of sulphur-containing compounds plays a pivotal role in the physiology of bacteria that live in aerobic soils where organosulfur compounds such as sulphonates and sulphate esters represent more than 95% of the available sulphur. Until now, no information has been available on the uptake of sulphonates by bacterial plant pathogens, particularly those of the Xanthomonas genus, which encompasses several pathogenic species. In the present study, we characterised the alkanesulphonate uptake system (Ssu) of Xanthomonas axonopodis pv. citri 306 strain (X. citri), the etiological agent of citrus canker. METHODOLOGY/PRINCIPAL FINDINGS: A single operon-like gene cluster (ssuEDACB) that encodes both the sulphur uptake system and enzymes involved in desulphurisation was detected in the genomes of X. citri and of the closely related species. We characterised X. citri SsuA protein, a periplasmic alkanesulphonate-binding protein that, together with SsuC and SsuB, defines the alkanesulphonate uptake system. The crystal structure of SsuA bound to MOPS, MES and HEPES, which is herein described for the first time, provides evidence for the importance of a conserved dipole in sulphate group coordination, identifies specific amino acids interacting with the sulphate group and shows the presence of a rather large binding pocket that explains the rather wide range of molecules recognised by the protein. Isolation of an isogenic ssuA-knockout derivative of the X. citri 306 strain showed that disruption of alkanesulphonate uptake affects both xanthan gum production and generation of canker lesions in sweet orange leaves. CONCLUSIONS/SIGNIFICANCE: The present study unravels unique structural and functional features of the X. citri SsuA protein and provides the first experimental evidence that an ABC uptake system affects the virulence of this phytopathogen.


Assuntos
Alcanossulfonatos/química , Proteínas de Bactérias/genética , Proteínas de Transporte/genética , Citrus sinensis/microbiologia , Xanthomonas/patogenicidade , Alcanossulfonatos/metabolismo , Sequência de Aminoácidos , Proteínas de Bactérias/química , Proteínas de Bactérias/fisiologia , Sítios de Ligação , Proteínas de Transporte/química , Proteínas de Transporte/fisiologia , Citrus sinensis/crescimento & desenvolvimento , Citrus sinensis/metabolismo , Modelos Moleculares , Dados de Sequência Molecular , Doenças das Plantas/microbiologia , Polissacarídeos Bacterianos/metabolismo , Alinhamento de Sequência , Virulência , Difração de Raios X , Xanthomonas/genética , Xanthomonas/metabolismo
9.
Curr Microbiol ; 66(3): 279-85, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23183956

RESUMO

Bacillus subtilis endospores have applications in different fields including their use as probiotics and antigen delivery vectors. Such specialized applications frequently require highly purified spore preparations. Nonetheless, quantitative data regarding both yields and purity of B. subtilis endospores after application of different growth conditions and purification methods are scarce or poorly reported. In the present study, we conducted several quantitative and qualitative analyses of growth conditions and purification procedures aiming generation of purified B. subtilis spores. Based on two growth media and different incubations conditions, sporulation frequencies up to 74.2 % and spore concentrations up to 7 × 10(9) spores/ml were achieved. Application of a simplified spore isolation method, in which samples were incubated with lysozyme and a detergent, resulted in preparations with highly purified spores at the highest yields. The present study represents, therefore, an important contribution for those working with B. subtilis endospores for different biotechnological purposes.


Assuntos
Bacillus subtilis/crescimento & desenvolvimento , Bacillus subtilis/fisiologia , Bacillus subtilis/citologia , Meios de Cultura , Esporos Bacterianos/citologia , Esporos Bacterianos/isolamento & purificação , Fatores de Tempo
10.
Clinics (Sao Paulo) ; 66(8): 1395-400, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21915490

RESUMO

OBJECTIVE: To evaluate the effects of a multidisciplinary rehabilitation program on cognition, quality of life, and neuropsychiatry symptoms in patients with mild Alzheimer's disease. METHOD: The present study was a single-blind, controlled study that was conducted at a university-based day-hospital memory facility. The study included 25 Alzheimer's patients and their caregivers and involved a 12-week stimulation and psychoeducational program. The comparison group consisted of 16 Alzheimer's patients in waiting lists for future intervention. INTERVENTION: Group sessions were provided by a multiprofessional team and included memory training, computer-assisted cognitive stimulation, expressive activities (painting, verbal expression, writing), physiotherapy, and physical training. Treatment was administered twice a week during 6.5-h gatherings. MEASUREMENTS: The assessment battery comprised the following tests: Mini-Mental State Examination, Short Cognitive Test, Quality of Life in Alzheimer's disease, Neuropsychiatric Inventory, and Geriatric Depression Scale. Test scores were evaluated at baseline and the end of the study by raters who were blinded to the group assignments. RESULTS: Measurements of global cognitive function and performance on attention tasks indicated that patients in the experimental group remained stable, whereas controls displayed mild but significant worsening. The intervention was associated with reduced depression symptoms for patients and caregivers and decreased neuropsychiatric symptoms in Alzheimer's subjects. The treatment was also beneficial for the patients' quality of life. CONCLUSION: This multimodal rehabilitation program was associated with cognitive stability and significant improvements in the quality of life for Alzheimer's patients. We also observed a significant decrease in depressive symptoms and caregiver burden. These results support the notion that structured nonpharmacological interventions can yield adjunct and clinically relevant benefits in dementia treatment.


Assuntos
Doença de Alzheimer/reabilitação , Cuidadores/psicologia , Transtornos Cognitivos/reabilitação , Equipe de Assistência ao Paciente , Qualidade de Vida/psicologia , Idoso , Doença de Alzheimer/complicações , Doença de Alzheimer/psicologia , Transtornos Cognitivos/etiologia , Transtornos Cognitivos/psicologia , Terapia Combinada , Feminino , Humanos , Masculino , Método Simples-Cego , Resultado do Tratamento
11.
Clinics ; 66(8): 1395-1400, 2011. tab
Artigo em Inglês | LILACS | ID: lil-598382

RESUMO

OBJECTIVE: To evaluate the effects of a multidisciplinary rehabilitation program on cognition, quality of life, and neuropsychiatry symptoms in patients with mild Alzheimer's disease. METHOD: The present study was a single-blind, controlled study that was conducted at a university-based day-hospital memory facility. The study included 25 Alzheimer's patients and their caregivers and involved a 12-week stimulation and psychoeducational program. The comparison group consisted of 16 Alzheimer's patients in waiting lists for future intervention. INTERVENTION: Group sessions were provided by a multiprofessional team and included memory training, computer-assisted cognitive stimulation, expressive activities (painting, verbal expression, writing), physiotherapy, and physical training. Treatment was administered twice a week during 6.5-h gatherings. MEASUREMENTS: The assessment battery comprised the following tests: Mini-Mental State Examination, Short Cognitive Test, Quality of Life in Alzheimer's disease, Neuropsychiatric Inventory, and Geriatric Depression Scale. Test scores were evaluated at baseline and the end of the study by raters who were blinded to the group assignments. RESULTS: Measurements of global cognitive function and performance on attention tasks indicated that patients in the experimental group remained stable, whereas controls displayed mild but significant worsening. The intervention was associated with reduced depression symptoms for patients and caregivers and decreased neuropsychiatric symptoms in Alzheimer's subjects. The treatment was also beneficial for the patients' quality of life. CONCLUSION: This multimodal rehabilitation program was associated with cognitive stability and significant improvements in the quality of life for Alzheimer's patients. We also observed a significant decrease in depressive symptoms and caregiver burden. These results support the notion that structured nonpharmacological interventions can yield adjunct and clinically relevant benefits in dementia treatment.


Assuntos
Idoso , Feminino , Humanos , Masculino , Doença de Alzheimer/reabilitação , Cuidadores/psicologia , Transtornos Cognitivos/reabilitação , Equipe de Assistência ao Paciente , Qualidade de Vida/psicologia , Doença de Alzheimer/complicações , Doença de Alzheimer/psicologia , Terapia Combinada , Transtornos Cognitivos/etiologia , Transtornos Cognitivos/psicologia , Método Simples-Cego , Resultado do Tratamento
14.
FEMS Immunol Med Microbiol ; 59(2): 131-42, 2010 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-20402772

RESUMO

The oral pathogen Streptococcus mutans expresses a surface protein, P1, which interacts with the salivary pellicle on the tooth surface or with fluid-phase saliva, resulting in bacterial adhesion or aggregation, respectively. P1 is a target of protective immunity. Its N-terminal region has been associated with adhesion and aggregation functions and contains epitopes recognized by efficacious antibodies. In this study, we used Bacillus subtilis, a gram-positive expression host, to produce a recombinant N-terminal polypeptide of P1 (P1(39-512)) derived from the S. mutans strain UA159. Purified P1(39-512) reacted with an anti-full-length P1 antiserum as well as one raised against intact S. mutans cells, indicating preserved antigenicity. Immunization of mice with soluble and heat-denatured P1(39-512) induced antibodies that reacted specifically with native P1 on the surface of S. mutans cells. The anti-P1(39-512) antiserum was as effective at blocking saliva-mediated aggregation of S. mutans cells and better at blocking bacterial adhesion to saliva-coated plastic surfaces compared with the anti-full-length P1 antiserum. In addition, adsorption of the anti-P1 antiserum with P1(39-512) eliminated its ability to block the adhesion of S. mutans cells to abiotic surfaces. The present results indicate that P1(39-512), expressed and purified from a recombinant B. subtilis strain, maintains important immunological features of the native protein and represents an additional tool for the development of anticaries vaccines.


Assuntos
Adesinas Bacterianas/imunologia , Anticorpos Antibacterianos/sangue , Anticorpos Neutralizantes/sangue , Bacillus subtilis/genética , Streptococcus mutans/imunologia , Adesinas Bacterianas/genética , Animais , Aderência Bacteriana/imunologia , Vetores Genéticos , Camundongos , Camundongos Endogâmicos BALB C , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Streptococcus mutans/genética
15.
Clinical vaccine immunology ; 17(4): 529-536, apr.2010.
Artigo em Inglês | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP, SESSP-IBACERVO | ID: biblio-1062098

RESUMO

Shiga-like toxin 2 (Stx2)-producing enterohemorrhagic Escherichia coli (referred to as EHEC or STEC) strainsare the primary etiologic agents of hemolytic-uremic syndrome (HUS), which leads to renal failure and highmortality rates. Expression of Stx2 is the most relevant virulence-associated factor of EHEC strains, and toxin neutralization by antigen-specific serum antibodies represents the main target for both preventive and therapeuticanti-HUS approaches. In the present report, we describe two Salmonella enterica serovar Typhimurium aroA vaccine strains expressing a nontoxic plasmid-encoded derivative of Stx2 (Stx2 AB) containing the complete nontoxic A2 subunit and the receptor binding B subunit. The two S. Typhimurium strains differ inthe expression of flagellin, the structural subunit of the flagellar shaft, which exerts strong adjuvant effects. Thevaccine strains expressed Stx2 AB, either cell bound or secreted into the extracellular environment, andshowed enhanced mouse gut colonization and high plasmid stability under both in vitro and in vivo conditions.Oral immunization of mice with three doses of the S. Typhimurium vaccine strains elicited serum anti-Stx2B(IgG) antibodies that neutralized the toxic effects of the native toxin under in vitro conditions (Vero cells) andconferred partial protection under in vivo conditions. No significant differences with respect to gut colonization or the induction of antigen-specific antibody responses were detected in mice vaccinated with flagellated versus nonflagellated bacterial strains. The present results indicate that expression of Stx2 AB by attenuated S. Typhimurium strains is an alternative vaccine approach for HUS control, but additional improvements in the immunogenicity of Stx2 toxoids are still required.


Assuntos
Humanos , Camundongos , Células Vero/microbiologia , Escherichia coli Enteropatogênica/imunologia , Vacinas , Escherichia coli/crescimento & desenvolvimento , Escherichia coli/isolamento & purificação , Escherichia coli/metabolismo , Salmonella enterica
16.
Clin Vaccine Immunol ; 17(4): 529-36, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20147499

RESUMO

Shiga-like toxin 2 (Stx2)-producing enterohemorrhagic Escherichia coli (referred to as EHEC or STEC) strains are the primary etiologic agents of hemolytic-uremic syndrome (HUS), which leads to renal failure and high mortality rates. Expression of Stx2 is the most relevant virulence-associated factor of EHEC strains, and toxin neutralization by antigen-specific serum antibodies represents the main target for both preventive and therapeutic anti-HUS approaches. In the present report, we describe two Salmonella enterica serovar Typhimurium aroA vaccine strains expressing a nontoxic plasmid-encoded derivative of Stx2 (Stx2DeltaAB) containing the complete nontoxic A2 subunit and the receptor binding B subunit. The two S. Typhimurium strains differ in the expression of flagellin, the structural subunit of the flagellar shaft, which exerts strong adjuvant effects. The vaccine strains expressed Stx2DeltaAB, either cell bound or secreted into the extracellular environment, and showed enhanced mouse gut colonization and high plasmid stability under both in vitro and in vivo conditions. Oral immunization of mice with three doses of the S. Typhimurium vaccine strains elicited serum anti-Stx2B (IgG) antibodies that neutralized the toxic effects of the native toxin under in vitro conditions (Vero cells) and conferred partial protection under in vivo conditions. No significant differences with respect to gut colonization or the induction of antigen-specific antibody responses were detected in mice vaccinated with flagellated versus nonflagellated bacterial strains. The present results indicate that expression of Stx2DeltaAB by attenuated S. Typhimurium strains is an alternative vaccine approach for HUS control, but additional improvements in the immunogenicity of Stx2 toxoids are still required.


Assuntos
Escherichia coli Êntero-Hemorrágica/imunologia , Infecções por Escherichia coli/prevenção & controle , Vacinas contra Escherichia coli/imunologia , Vetores Genéticos , Salmonella typhimurium/genética , Toxina Shiga II/imunologia , Administração Oral , Animais , Anticorpos Antibacterianos/sangue , Anticorpos Neutralizantes/sangue , Antitoxinas/sangue , Chlorocebus aethiops , Creatinina/sangue , Infecções por Escherichia coli/imunologia , Vacinas contra Escherichia coli/administração & dosagem , Vacinas contra Escherichia coli/genética , Imunização Secundária , Camundongos , Camundongos Endogâmicos BALB C , Toxina Shiga II/biossíntese , Ureia/sangue , Vacinas Atenuadas/administração & dosagem , Vacinas Atenuadas/genética , Vacinas Atenuadas/imunologia , Células Vero
17.
Genet Mol Biol ; 33(2): 341-7, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21637492

RESUMO

In this study we investigated the prevalence of the oppA gene, encoding the oligopeptide binding protein (OppA) of the major bacterial oligopeptide uptake system (Opp), in different species of the genus Xanthomonas. The oppA gene was detected in two Xanthomonas axonopodis strains among eight tested Xanthomonas species. The generation of an isogenic oppA-knockout derivative of the Xac 306 strain, showed that the OppA protein neither plays a relevant role in oligopeptide uptake nor contributes to the infectivity and multiplication of the bacterial strain in leaves of sweet orange (Citrus sinensis) and Rangpur lime (Citrus limonia). Taken together these results suggest that the oppA gene has a recent evolutionary history in the genus and does not contribute in the physiology or pathogenesis of X. axonopodis.

18.
Genet. mol. biol ; 33(2): 341-347, 2010. ilus, graf, tab
Artigo em Inglês | LILACS-Express | LILACS, Sec. Est. Saúde SP | ID: lil-548826

RESUMO

In this study we investigated the prevalence of the oppA gene, encoding the oligopeptide binding protein (OppA) of the major bacterial oligopeptide uptake system (Opp), in different species of the genus Xanthomonas. The oppA gene was detected in two Xanthomonas axonopodis strains among eight tested Xanthomonas species. The generation of an isogenic oppA-knockout derivative of the Xac 306 strain, showed that the OppA protein neither plays a relevant role in oligopeptide uptake nor contributes to the infectivity and multiplication of the bacterial strain in leaves of sweet orange (Citrus sinensis) and Rangpur lime (Citrus limonia). Taken together these results suggest that the oppA gene has a recent evolutionary history in the genus and does not contribute in the physiology or pathogenesis of X. axonopodis.

19.
Arq Bras Endocrinol Metabol ; 53(7): 804-10, 2009 Oct.
Artigo em Português | MEDLINE | ID: mdl-19942981

RESUMO

OBJECTIVE AND METHODS: To investigate the utility of nuclear chromatin texture assessment in the differential diagnosis of follicular patterned lesions, by means of examining 76 samples previously submitted to the immunohistochemical protein analysis of HBME-1, CK-19 and galectina-3. RESULTS: HBME-1 confirmed to be the most sensitive marker of malignancy. A series of morphometric, densitometric and texture variables were useful in the discrimination of the different types of follicular lesions. Among these variables, r(2), a parameter related to the granularity of the nucleus presented the best accuracy, sensitivity, specificity and positive and negative predictive values, distinguishing benign from malignant lesions. CONCLUSION: The morphometric analysis of nuclear chromatin images may add accuracy to the differential diagnosis of follicular patterned lesions.


Assuntos
Adenoma/patologia , Biomarcadores Tumorais/análise , Carcinoma Papilar, Variante Folicular/patologia , Núcleo Celular/patologia , Cromatina/patologia , Neoplasias da Glândula Tireoide/patologia , Adenoma/ultraestrutura , Carcinoma Papilar, Variante Folicular/ultraestrutura , Cromatina/ultraestrutura , Diagnóstico por Computador/métodos , Diagnóstico Diferencial , Galectina 3/análise , Humanos , Queratina-19/análise , Valor Preditivo dos Testes , Software , Neoplasias da Glândula Tireoide/ultraestrutura
20.
Arq. bras. endocrinol. metab ; 53(7): 804-810, out. 2009. ilus, graf, tab
Artigo em Português | LILACS | ID: lil-531693

RESUMO

OBJETIVO E MÉTODOS: Com o propósito de investigar a contribuição do exame da cromatina nuclear no diagnóstico diferencial das lesões foliculares da glândula tireoide, foram estudadas 76 amostras previamente submetidas à análise de expressão proteica de HBME-1, CK-19 e galectina-3. RESULTADOS: HBME-1 confirmou-se como o mais sensível marcador imunoistoquímico de malignidade. Uma série de variáveis morfométricas, densitométricas e de textura foram úteis na distinção entre os diferentes tipos de lesão folicular. Entre essas variáveis, o r², parâmetro relacionado à granularidade do núcleo, apresentou a melhor acurácia, sensibilidade, especificidade, valor preditivo positivo e negativo, diferenciando lesões benignas de malignas. CONCLUSÃO: A morfometria analítica de imagem da cromatina nuclear pode acrescentar acurácia ao diagnóstico diferencial das lesões de padrão folicular.


OBJECTIVE AND METHODS: To investigate the utility of nuclear chromatin texture assessment in the differential diagnosis of follicular patterned lesions, by means of examining 76 samples previously submitted to the immunohistochemical protein analysis of HBME-1, CK-19 and galectina-3. RESULTS: HBME-1 confirmed to be the most sensitive marker of malignancy. A series of morphometric, densitometric and texture variables were useful in the discrimination of the different types of follicular lesions. Among these variables, r², a parameter related to the granularity of the nucleus presented the best accuracy, sensitivity, specificity and positive and negative predictive values, distinguishing benign from malignant lesions. CONCLUSION: The morphometric analysis of nuclear chromatin images may add accuracy to the differential diagnosis of follicular patterned lesions.


Assuntos
Humanos , Adenoma/patologia , Carcinoma Papilar, Variante Folicular/patologia , Núcleo Celular/patologia , Cromatina/patologia , Neoplasias da Glândula Tireoide/patologia , Biomarcadores Tumorais/análise , Adenoma/ultraestrutura , Carcinoma Papilar, Variante Folicular/ultraestrutura , Cromatina/ultraestrutura , Diagnóstico Diferencial , Diagnóstico por Computador/métodos , /análise , /análise , Valor Preditivo dos Testes , Software , Neoplasias da Glândula Tireoide/ultraestrutura
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