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1.
Anticancer Res ; 43(4): 1397-1405, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36974776

RESUMO

BACKGROUND/AIM: Small cell neuroendocrine carcinoma of the cervix (SCNEC) is a rare disease characterized by a higher incidence of lymphatic invasion, metastasis, and recurrence compared to the squamous cell carcinoma and adenocarcinoma subtypes. Furthermore, it is prone to early distant metastasis and has a poor prognosis. Chemotherapy has an important role in the management of cervical SCNEC. The effective treatment schemes for early-stage SCNEC are local treatment with radical surgery and systemic chemotherapy. However no standard treatment regimen exists because of a rare disease. We reviewed previous reports to determine whether etoposide/platinum, which is used for histopathologically similar small cell carcinoma of the lung, is an appropriate initial chemotherapy regimen for SCNEC of the cervix. MATERIALS AND METHODS: In this review the Cochrane library sources, ClinicalTrials.gov, Web of Silence, PubMed and search engine of Google scholar were searched for all interventional studies, reviews, case reports and meta-analyses published in 1997-2021. RESULTS: Etoposide/platinum (EP) is the most commonly used regimen and paclitaxel/carboplatin is the second most common, used as a part of multimodality therapy for SCNEC of the cervix in most studies. Cisplatin/vincristine/bleomycin, cisplatin/irinotecan, cisplatin/ifosfamide/etoposide were also reported in concurrence with EP; however no clinical trials are dedicated to SCNEC. CONCLUSION: Etoposide and platinum tend to have a better prognosis compared to other regimens used for other subtypes of cervical cancer. For recurrent cervical SCNEC, treatment options for patients are very limited. The application of molecular testing for targeted mutations may suggest potential future therapies that may be useful in this disease.


Assuntos
Carcinoma Neuroendócrino , Carcinoma de Células Pequenas , Neoplasias Pulmonares , Carcinoma de Pequenas Células do Pulmão , Neoplasias do Colo do Útero , Feminino , Humanos , Carcinoma de Células Pequenas/patologia , Colo do Útero/patologia , Cisplatino , Neoplasias do Colo do Útero/patologia , Carcinoma Neuroendócrino/patologia , Etoposídeo/uso terapêutico , Platina/uso terapêutico , Doenças Raras/tratamento farmacológico , Estadiamento de Neoplasias , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma de Pequenas Células do Pulmão/tratamento farmacológico , Ifosfamida/uso terapêutico , Neoplasias Pulmonares/patologia
2.
Sci Rep ; 12(1): 8485, 2022 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-35590028

RESUMO

Enterococcus faecalis is a natural inhabitant of the human gastrointestinal tract. This bacterial species is subdominant in a healthy physiological state of the gut microbiota (eubiosis) in adults, but can become dominant and cause infections when the intestinal homeostasis is disrupted (dysbiosis). The relatively high concentrations of bile acids deoxycholate (DCA) and taurocholate (TCA) hallmark eubiosis and dysbiosis, respectively. This study aimed to better understand how E. faecalis adapts to DCA and TCA. We showed that DCA impairs E. faecalis growth and possibly imposes a continuous adjustment in the expression of many essential genes, including a majority of ribosomal proteins. This may account for slow growth and low levels of E. faecalis in the gut. In contrast, TCA had no detectable growth effect. The evolving transcriptome upon TCA adaptation showed the early activation of an oligopeptide permease system (opp2) followed by the adjustment of amino acid and nucleotide metabolisms. We provide evidence that TCA favors the exploitation of oligopeptide resources to fuel amino acid needs in limiting oligopeptide conditions. Altogether, our data suggest that the combined effects of decreased DCA and increased TCA concentrations can contribute to the rise of E. faecalis population during dysbiosis.


Assuntos
Ácidos e Sais Biliares , Enterococcus faecalis , Aminoácidos/metabolismo , Ácidos e Sais Biliares/metabolismo , Ácido Desoxicólico/metabolismo , Ácido Desoxicólico/farmacologia , Disbiose , Enterococcus faecalis/genética , Humanos , Ácido Taurocólico/metabolismo , Ácido Taurocólico/farmacologia
3.
J Appl Microbiol ; 130(6): 2075-2086, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33124086

RESUMO

AIMS: Allergic asthma is a chronic inflammatory lung disease characterized by a Th2-type immune response pattern. The development of nonspecific immunotherapy is one of the primary goals for the control of this disease. METHODS AND RESULTS: In this study, we evaluated the therapeutic effects of Lactococcus lactis-producing mycobacterial heat shock protein 65 (LLHsp65) in an ovalbumin (OVA)-induced allergic asthma model. OVA-challenged BALB/c mice were orally administrated with LLHsp65 for 10 consecutive days. The results demonstrate that LLhsp65 attenuates critical features of allergic inflammation, like airway hyperresponsiveness and mucus production. Likewise, the treatment decreases the pulmonary eosinophilia and the serum level of OVA-specific IgE. In addition to deviating immune responses towards Th1-cytokine profile, increase regulatory T cells, and cytokine levels, such as IL-6 and IL-10. CONCLUSIONS: Our results reveal that the mucosal immunotherapy of LLHsp65 significantly reduces the overall burden of airway allergic inflammation, suggesting a promising therapeutic strategy for allergic asthma treatment. SIGNIFICANCE AND IMPACT OF THE STUDY: This research reveals new perspectives on nonspecific immunotherapy based on the delivery of recombinant proteins by lactic acid bacteria to treat of allergic disorders.


Assuntos
Asma/tratamento farmacológico , Proteínas de Bactérias/farmacologia , Chaperonina 60/farmacologia , Inflamação/tratamento farmacológico , Lactococcus lactis/imunologia , Administração Oral , Animais , Asma/imunologia , Líquido da Lavagem Broncoalveolar/citologia , Citocinas/metabolismo , Modelos Animais de Doenças , Feminino , Hipersensibilidade/tratamento farmacológico , Imunoglobulina E/sangue , Imunoglobulina G/sangue , Imunoterapia , Lactococcus lactis/metabolismo , Pulmão/efeitos dos fármacos , Pulmão/imunologia , Pulmão/patologia , Camundongos , Camundongos Endogâmicos BALB C , Ovalbumina , Linfócitos T Reguladores/imunologia
4.
J Appl Microbiol ; 129(5): 1389-1401, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32473073

RESUMO

AIMS: To investigate the anti-inflammatory activity of an invasive and Hp65-producing strain Lactococcus lactis NCDO2118 FnBPA+ (pXYCYT:Hsp65) in acute 2,4,6-trinitrobenzene sulphonic acid (TNBS)-induced colitis in mice as an innovative therapeutic strategy against Crohn's disease (CD). METHODS AND RESULTS: The pXYCYT:Hsp65 plasmid was transformed into the L. lactis NCDO2118 FnBPA+ strain, resulting in the L. lactis NCDO2118 FnBPA+ (pXYCYT:Hsp65) strain. Then, the functionality of the strain was evaluated in vitro for Hsp65 production by Western blotting and for invasion into Caco-2 cells. The results demonstrated that the strain was able to produce Hsp65 and efficiently invade eukaryotic cells. Subsequently, in vivo, the anti-inflammatory capacity of the recombinant strain was evaluated in colitis induced with TNBS in BALB/c mice. Oral administration of the recombinant strain was able to attenuated the severity of colitis by mainly reducing IL-12 and IL-17 levels and increasing IL-10 and secretory immunoglobulin A levels. CONCLUSIONS: The L. lactis NCDO2118 FnBPA+ (pXYCYT:Hsp65) strain contributed to a reduction in inflammatory damage in experimental CD. SIGNIFICANCE AND IMPACT OF THE STUDY: This study, which used L. lactis for the production and delivery of Hsp65, has scientific relevance because it shows the efficacy of this new strategy based on therapeutic protein delivery into mammalian enterocytes.


Assuntos
Proteínas de Bactérias/metabolismo , Chaperonina 60/metabolismo , Colite/terapia , Imunoglobulina A Secretora/metabolismo , Interleucina-10/metabolismo , Lactococcus lactis/fisiologia , Administração Oral , Animais , Proteínas de Bactérias/genética , Células CACO-2 , Chaperonina 60/genética , Colite/induzido quimicamente , Colite/imunologia , Sistemas de Liberação de Medicamentos , Feminino , Humanos , Inflamação/terapia , Lactococcus lactis/genética , Lactococcus lactis/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Ácido Trinitrobenzenossulfônico/toxicidade
5.
J Appl Microbiol ; 122(6): 1657-1662, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28314076

RESUMO

AIMS: A regimen utilizing Bacille Calmette-Guerin (BCG) and another vaccine system as a booster may represent a promising strategy for the development of an efficient tuberculosis vaccine for adults. In a previous work, we confirmed the ability of Lactococcus lactis fibronectin-binding protein A (FnBPA+) (pValac:ESAT-6), a live mucosal DNA vaccine, to produce a specific immune response in mice after oral immunization. In this study, we examined the immunogenicity of this strain as a booster for the BCG vaccine in mice. METHODS AND RESULTS: After immunization, cytokine and immunoglobulin profiles were measured. The BCG prime L. lactis FnBPA+ (pValac:ESAT-6) boost group was the most responsive group, with a significant increase in splenic pro-inflammatory cytokines IL-17, IFN-γ, IL-6 and TNF-α compared with the negative control. CONCLUSIONS: Based on the results obtained here, we demonstrated that L. lactis FnBPA+ (pValac:ESAT-6) was able to increase the BCG vaccine general immune response. SIGNIFICANCE AND IMPACT OF THE STUDY: This work is of great scientific and social importance because it represents the first step towards the development of a booster to the BCG vaccine using L. lactis as a DNA delivery system.


Assuntos
Antígenos de Bactérias/imunologia , Vacina BCG/imunologia , Proteínas de Bactérias/imunologia , Citocinas/sangue , Interleucina-17/metabolismo , Lactococcus lactis/genética , Vacinas de DNA/imunologia , Animais , Antígenos de Bactérias/genética , Proteínas de Bactérias/genética , Feminino , Interleucina-6 , Lactococcus lactis/metabolismo , Camundongos , Fator de Necrose Tumoral alfa
6.
J Appl Microbiol ; 120(2): 432-40, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26551688

RESUMO

AIMS: Propionibacterium freudenreichii is an actinobacterium widely used in dairy industry during the ripening process of Swiss-type cheeses and which presents probiotic properties. P. freudenreichii is reportedly a hardy bacterium, able to survive during the cheese-making process and when subjected to digestive stresses. During this study the long-term survival (LTS) of P. freudenreichii was investigated for 11 days by means of phenotypic characterization in a culture medium without the addition of any nutrients. METHODS AND RESULTS: For 11 days, in a non-nutrient supplemented culture medium, eight strains were monitored by measuring their optical density, counting colony-forming units (CFU) and using LIVE/DEAD staining and microscopy observation. Under these conditions, all strains displayed high survival rates in the culture medium, their culturability reaching more than 9 log10 CFU ml(-1) after 2 days. After 11 days, this value ranged from 7·8 to 8·2 log10 CFU ml(-1) depending on the strain, and at least 50% of the P. freudenreichii population displayed an intact envelope. As lysis of part of a bacterial population may be a microbial strategy to recover nutrients, in CIRM-BIA 138 (the strain with the highest population at day 11), cell lysis was assessed by quantifying intact bacterial cells using qPCR targeting the housekeeping gene tuf. No lysis was observed. CONCLUSION: Taken together, our results suggest that P. freudenreichii strains use a viable but nonculturable state to adapt to the LTS phase. SIGNIFICANCE AND IMPACT OF THE STUDY: Assessing the viability of P. freudenreichii and understanding their mechanisms for survival should be of great interest regarding their potential probiotic applications.


Assuntos
Meios de Cultura/metabolismo , Propionibacterium/crescimento & desenvolvimento , Meios de Cultura/análise , Viabilidade Microbiana , Propionibacterium/metabolismo
7.
Genet Mol Res ; 14(4): 18485-93, 2015 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-26782496

RESUMO

In this study, Lactococcus lactis was engineered to express mutated internalin A on its surface and to secrete large amounts of listeriolysin O (LLO) in order to improve its potential as a vehicle for DNA vaccination. Western blotting experiments demonstrated that the bacterium expressed LLO in both the cytoplasmic and extracellular compartments, with higher quantities found in the culture supernatants. A hemolytic assay showed that the recombinant strain secreted 250 ng active LLO/mg total protein. This mInlA/LLO-producing strain of L. lactis may be used as an alternative tool in DNA vaccination against a number of infectious diseases or in cancer therapy.


Assuntos
Proteínas de Bactérias/genética , Proteínas de Bactérias/imunologia , Toxinas Bacterianas/genética , Toxinas Bacterianas/imunologia , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/imunologia , Proteínas Hemolisinas/genética , Proteínas Hemolisinas/imunologia , Lactococcus lactis/genética , Listeria monocytogenes/imunologia , Mutação , Proteínas Recombinantes , Vacinas Bacterianas , Membrana Celular/metabolismo , Expressão Gênica , Hemólise , Lactococcus lactis/metabolismo , Vacinação
8.
Genet Mol Res ; 13(3): 5073-87, 2014 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-25061732

RESUMO

The human genome project is one of the significant achievements that have provided detailed insight into our genetic legacy. During the last two decades, biomedical investigations have gathered a considerable body of evidence by detecting more than 2000 disease genes. Despite the imperative advances in the genetic understanding of various diseases, the pathogenesis of many others remains obscure. With recent advances, the laborious methodologies used to identify DNA variations are replaced by direct sequencing of genomic DNA to detect genetic changes. The ability to perform such studies depends equally on the development of high-throughput and economical genotyping methods. Currently, basically for every disease whose origen is still unknown, genetic approaches are available which could be pedigree-dependent or -independent with the capacity to elucidate fundamental disease mechanisms. Computer algorithms and programs for linkage analysis have formed the foundation for many disease gene detection projects, similarly databases of clinical findings have been widely used to support diagnostic decisions in dysmorphology and general human disease. For every disease type, genome sequence variations, particularly single nucleotide polymorphisms are mapped by comparing the genetic makeup of case and control groups. Methods that predict the effects of polymorphisms on protein stability are useful for the identification of possible disease associations, whereas structural effects can be assessed using methods to predict stability changes in proteins using sequence and/or structural information.


Assuntos
Ligação Genética , Genoma Humano , Biologia Molecular/tendências , Software , Biologia Computacional , Bases de Dados Genéticas , Predisposição Genética para Doença , Humanos , Biologia Molecular/instrumentação , Biologia Molecular/métodos , Linhagem , Polimorfismo Genético , Análise de Sequência de DNA
9.
Benef Microbes ; 5(4): 409-19, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24939801

RESUMO

The effect of intestinal colonisation on the immune system was investigated in germ-free mice monoassociated with Lactobacillus strains isolated from calf faeces. Single doses of Lactobacillus acidophilus L36 or Lactobacillus salivarius L38 were administered to germ-free mice by intragastric gavage. Ten days later, the mice were euthanised. Gene expression levels of interleukin 5 (IL-5), IL-6, IL-10, IL-12b, IL-17a, gamma interferon (IFN-γ), transforming growth factor beta 1 (TGF-ß1), and tumour necrosis factor alpha (TNF-α) were quantified in segments of the small and large intestines by real time quantitative polymerase chain reaction. All the mice were colonised rapidly after Lactobacillus administration with intestinal counts ranging from 6.53 to 8.26 log cfu/g. L. acidophilus L36 administration increased the expression of cytokines involved with the Th2 (IL-5, IL-6 and TGF-ß1) and Th17 (IL-17a, TNF-α and IL-6) inflammatory response, whereas L. salivarius L38 appeared to stimulate a pattern of less diversified cytokines in the intestine. Intragastric gavage of L. acidophilus L36 and L. salivarius L38 induced similar levels of colonisation in the digestive tracts of germ-free mice but stimulated different immune responses in the intestinal mucosa. The different immunomodulation patterns might facilitate the potential use of these lactobacilli as probiotics to treat distinct pathological conditions, for example protection against Citrobacter rodentium infection by stimulating IL-17 production.


Assuntos
Citocinas/biossíntese , Trato Gastrointestinal/imunologia , Trato Gastrointestinal/microbiologia , Vida Livre de Germes , Lactobacillus/crescimento & desenvolvimento , Lactobacillus/imunologia , Animais , Carga Bacteriana , Citocinas/genética , Perfilação da Expressão Gênica , Camundongos , Reação em Cadeia da Polimerase em Tempo Real
10.
Genet Mol Res ; 12(3): 2902-12, 2013 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-24065646

RESUMO

Streptococcus agalactiae (Lancefield group B; group B streptococci) is a major pathogen that causes meningoencephalitis in fish, mastitis in cows, and neonatal sepsis and meningitis in humans. The available prophylactic measures for conserving human and animal health are not totally effective and have limitations. Effective vaccines against the different serotypes or genotypes of pathogenic strains from the various hosts would be useful. We used an in silico strategy to identify conserved vaccine candidates in 15 genomes of group B streptococci strains isolated from human, bovine, and fish samples. The degree of conservation, subcellular localization, and immunogenic potential of S. agalactiae proteins were investigated. We identified 36 antigenic proteins that were conserved in all 15 genomes. Among these proteins, 5 and 23 were shared only by human or fish strains, respectively. These potential vaccine targets may help develop effective vaccines that will help prevent S. agalactiae infection.


Assuntos
Peixes/genética , Imunoterapia Ativa , Mastite Bovina/prevenção & controle , Infecções Estreptocócicas/prevenção & controle , Animais , Bovinos , Simulação por Computador , Feminino , Genoma Bacteriano , Humanos , Mastite Bovina/genética , Mastite Bovina/microbiologia , Terapia de Alvo Molecular , Infecções Estreptocócicas/genética , Infecções Estreptocócicas/imunologia , Infecções Estreptocócicas/veterinária , Streptococcus agalactiae/efeitos dos fármacos , Streptococcus agalactiae/genética , Streptococcus agalactiae/imunologia , Streptococcus agalactiae/patogenicidade
11.
Genet Mol Res ; 12(3): 2982-9, 2013 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-24065654

RESUMO

Due to next-generation sequence technologies, sequencing of bacterial genomes is no longer one of the main bottlenecks in bacterial research and the number of new genomes deposited in public databases continues to increase at an accelerating rate. Among these new genomes, several belong to the same species and were generated for pan-genomic studies. A pan-genomic study allows investigation of strain phenotypic differences based on genotypic differences. Along with a need for good assembly quality, it is also fundamental to guarantee good functional genome annotation of the different strains. In order to ensure quality and standards for functional genome annotation among different strains, we developed and made available PANNOTATOR (http://bnet.egr.vcu.edu/iioab/agenote.php), a web-based automated pipeline for the annotation of closely related and well-suited genomes for pan-genome studies, aiming at reducing the manual work to generate reports and corrections of various genome strains. PANNOTATOR achieved 98 and 76% of correctness for gene name and function, respectively, as result of an annotation transfer, with a similarity cut-off of 70%, compared with a gold standard annotation for the same species. These results surpassed the RAST and BASys softwares by 41 and 21% and 66 and 17% for gene name and function annotation, respectively, when there were reliable genome annotations of closely related species. PANNOTATOR provides fast and reliable pan-genome annotation; thereby allowing us to maintain the research focus on the main genotype differences between strains.


Assuntos
Genoma Bacteriano/genética , Anotação de Sequência Molecular , Software , Bases de Dados Genéticas , Sequenciamento de Nucleotídeos em Larga Escala
12.
J Appl Microbiol ; 115(2): 319-33, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23437848

RESUMO

Allergic diseases affect up to 30% of the western population, and their prevalence is increasing. Probiotics are able to modulate the mucosal immune response, and clinical trials demonstrated that specific strains, especially lactic acid bacteria (LAB) ones, reduce allergic symptoms. Moreover, the use of recombinant probiotics has been evaluated as possible strategies for the immunotherapy of allergic diseases. The production and delivery of allergens by recombinant LAB in concert with their ability to induce a Th1-type immune response have been shown to be a promising mucosal vaccination strategy in mouse model. The aim of this article is to review the applications of probiotics in allergy immunotherapy with a special focus on recombinant LAB delivering proteins or DNA.


Assuntos
Hipersensibilidade/terapia , Imunoterapia , Probióticos/uso terapêutico , Alérgenos/genética , Alérgenos/imunologia , Animais , Bifidobacterium/genética , DNA/administração & dosagem , Humanos , Hipersensibilidade/imunologia , Imunidade nas Mucosas , Lactobacillus/genética , Camundongos , Hipersensibilidade a Leite/terapia , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/imunologia
13.
Genet Mol Res ; 11(3): 2051-9, 2012 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-22911589

RESUMO

Corynebacterium pseudotuberculosis, the infectious agent of caseous lymphadenitis (CLA), is responsible for substantial economic losses in goat and sheep production. Molecular characterization of C. pseudotuberculosis isolates by enterobacterial repetitive intergenic consensus (ERIC)-PCR has shown promising results in genotyping strains isolated from sheep with CLA. We evaluated the genetic diversity of C. pseudotuberculosis isolates collected from the Sertão region of the Pernambuco (PE) State, Brazil, and investigated the potential of ERIC-PCR as a tool for the molecular typing of strains of C. pseudotuberculosis isolated from goats. Thirty-two C. pseudotuberculosis strains isolated from goats in the municipalities of Floresta and Ibimirim, PE, C. pseudotuberculosis type strain ATCC 19410, the 1002 vaccine strain, and a field isolate of Rhodococcus equi were fingerprinted using the primers ERIC-1R and ERIC-2 and the primer pair ERIC- 1R+ERIC-2. Using 100% similarity as the cutoff, 8, 10, and 7 genotypes were obtained with ERIC-1-PCR, ERIC-2-PCR, and ERIC-1+2-PCR, respectively. The Hunter-Gaston discriminatory index calculated for the ERIC-1-PCR was 0.75. The index for the ERIC-2-PCR was 0.88, and the index for the ERIC-1+2-PCR was 0.79. Among goat isolates of C. pseudotuberculosis, three, two and four genotypes (found by ERIC-1-PCR, ERIC-2-PCR, and ERIC-1+2-PCR, respectively) had been previously described among sheep isolates from Minas Gerais State, Brazil. These results showed that ERIC-PCR has good discriminatory power and typeability, making it a useful tool for discrimination among C. pseudotuberculosis isolates from goats.


Assuntos
Sequência Consenso/genética , Corynebacterium pseudotuberculosis/genética , Corynebacterium pseudotuberculosis/isolamento & purificação , DNA Intergênico/genética , Cabras/microbiologia , Reação em Cadeia da Polimerase/métodos , Sequências Repetitivas de Ácido Nucleico/genética , Animais , Brasil , Análise por Conglomerados , Impressões Digitais de DNA , Enterobacteriaceae/genética
14.
Genet Mol Res ; 11(2): 1146-57, 2012 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-22614283

RESUMO

Lactic acid bacteria (LAB) are an attractive and safe alternative for the expression of heterologous proteins, as they are nonpathogenic and endotoxin-free organisms. Lactococcus lactis, the LAB model organism, has been extensively employed in the biotechnology field for large-scale production of heterologous proteins, and its use as a "cell factory" has been widely studied. We have been particularly interested in the use of L. lactis for production of heat shock proteins (HSPs), which reportedly play important roles in the initiation of innate and adaptive immune responses. However, this activity has been questioned, as LPS contamination appears to be responsible for most, if not all, immunostimulatory activity of HSPs. In order to study the effect of pure HSPs on the immune system, we constructed recombinant L. lactis strains able to produce and properly address the Mycobacterium leprae 65-kDa HSP (Hsp65) to the cytoplasm or to the extracellular medium, using a xylose-induced expression system. Approximately 7 mg/L recombinant Hsp65 was secreted. Degradation products related to lactococcal HtrA activity were not observed, and the Limulus amebocyte lysate assay demonstrated that the amount of LPS in the recombinant Hsp65 preparations was 10-100 times lower than the permitted levels established by the U.S. Food and Drug Administration. These new L. lactis strains will allow investigation of the effects of M. leprae Hsp65 without the interference of LPS; consequently, they have potential for a variety of biotechnological, medical and therapeutic applications.


Assuntos
Proteínas de Bactérias/genética , Chaperonina 60/genética , Lactococcus lactis/metabolismo , Mycobacterium leprae/metabolismo , Sequência de Bases , Clonagem Molecular , Primers do DNA , Lactococcus lactis/genética , Mycobacterium leprae/genética , Reação em Cadeia da Polimerase , Proteínas Recombinantes/genética
15.
Epidemiol Infect ; 140(4): 617-20, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21669023

RESUMO

Invasive infections caused by Corynebacterium diphtheriae in vaccinated and non-vaccinated individuals have been reported increasingly. In this study we used multilocus sequence typing (MLST) to study genetic relationships between six invasive strains of this bacterium isolated solely in the urban area of Rio de Janeiro, Brazil, during a 10-year period. Of note, all the strains rendered negative results in PCR reactions for the tox gene, and four strains presented an atypical sucrose-fermenting ability. Five strains represented new sequence types. MLST results did not support the hypothesis that invasive (sucrose-positive) strains of C. diphtheriae are part of a single clonal complex. Instead, one of the main findings of the study was that such strains can be normally found in clonal complexes with strains related to non-invasive disease. Comparative analyses with C. diphtheriae isolated in different countries provided further information on the geographical circulation of some sequence types.


Assuntos
Corynebacterium diphtheriae/genética , Difteria/microbiologia , Adolescente , Adulto , Idoso , Técnicas de Tipagem Bacteriana , Brasil/epidemiologia , Criança , Difteria/epidemiologia , Feminino , Humanos , Masculino , Tipagem de Sequências Multilocus
16.
Vet Pathol ; 49(5): 839-45, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22156228

RESUMO

Spontaneous progressive nephropathy dominated by glomerular lesions in common marmosets has been reported. However, the histopathologic characteristics, including the relationship between glomerular and tubulointerstitial lesions, have not been described in detail. In the present study, the authors examined the histopathologic characteristics of the background renal lesions in common marmosets (3 males and 9 females, 3 to 8 years old). The severity of glomerular lesions was graded into 3 classes: grade I, no alteration; grade II, hilar/focal increase of mesangial matrix; grade III, global/diffuse increase of mesangial matrix. Tubulointerstitial lesions (tubular regeneration and hyperplasia and interstitial inflammation and fibrosis) were scored according to the area of each lesion. The renal lesions were characterized by enlargement of glomeruli, expanded mesangial area with increase of periodic acid-Schiff reaction-positive matrix, tubular regeneration and hyperplasia, and interstitial inflammation and fibrosis. Glomerular lesions progressed with increasing mesangial matrix and aging. Additionally, the tubulointerstitial lesions became exacerbated with progressing glomerular lesions. Tubular hyperplasia was divided into 4 types according to the structure of the cell layer (simple or stratified-like), the area of increased lining cells (partial or entire), cytoplasmic staining (eosinophilic or basophilic), brush border and thickness of basement membrane, and the activity of cell proliferation. In conclusion, the background renal lesions in common marmosets were characterized by glomerular lesions with increase of mesangial matrix, which progressed with aging, and secondary tubulointerstitial lesions, including tubular hyperplasia. Those lesions were thus diagnosed as progressive glomerulonephropathy in common marmosets.


Assuntos
Callithrix , Hiperplasia/veterinária , Nefropatias/veterinária , Rim/patologia , Doenças dos Macacos/patologia , Fatores Etários , Animais , Membrana Basal/patologia , Feminino , Fibrose/patologia , Fibrose/veterinária , Mesângio Glomerular/patologia , Hiperplasia/patologia , Imuno-Histoquímica/veterinária , Nefropatias/patologia , Glomérulos Renais/patologia , Túbulos Renais/patologia , Masculino
17.
Genet Mol Res ; 10(3): 1707-18, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21863565

RESUMO

The large number of microbial genomes deposited in databanks has opened the door for in-depth studies of organisms, including post-genomics investigations. Thanks to new generation sequencing technology, these studies have made advances that have lead to extraordinary discoveries in bacterial transcriptomics. In this review, we describe bacterial RNA sequencing studies that use these new techniques. We also examined the advantages and biases of these new generation technologies; advances in bioinformatics make it possible to overcome the biases, providing interesting and surprising results.


Assuntos
Bactérias/genética , Genoma Bacteriano , RNA Bacteriano/química , Transcriptoma , Sequência de Bases , RNA Bacteriano/genética , Análise de Sequência de RNA/métodos
18.
Genet Mol Res ; 10(2): 1290-4, 2011 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-21732292

RESUMO

Despite the existence of a vaccine against diphtheria, this disease remains endemic and is reemerging in several regions due to many factors, including variations in genes coding for virulence factors. One common feature of virulence factors is their high concentration in pathogenicity islands (PAIs), very unstable regions acquired via horizontal gene transfer, which has lead to the emergence of various bacterial pathogens. The 13 putative PAIs in Corynebacterium diphtheriae NCTC 13129 and the reemergence of this disease point to the great variability in the PAIs of this species, which may reflect on bacterial life style and physiological versatility. We investigated the relationships between the large number of PAIs in C. diphtheriae and the possible implications of their plasticity in virulence. The GenoFrag software was used to design primers to analyze the genome plasticity of two pathogenicity islands of the reference strain (PiCds 3 and 8) in 11 different strains. We found that PiCd 3 was absent in only two strains, showing genes playing putative important roles in virulence and that only one strain harbored PiCd 8, due to its location in a putative "hotspot" for horizontal gene transfer events.


Assuntos
Corynebacterium diphtheriae/patogenicidade , Reação em Cadeia da Polimerase/métodos , Virulência/genética , Sequência de Bases , Corynebacterium diphtheriae/genética , Primers do DNA , Genes Bacterianos
19.
Gene ; 482(1-2): 1-7, 2011 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-21497183

RESUMO

Corynebacterium spp. are a group of Gram-positive bacteria that includes plant and animal pathogens, nonpathogenic soil bacteria, and saprophytic species. Our understanding of these organisms is still poor compared with that of other bacterial organisms, but new insights offered by genome sequence data and the elucidation of gene content has provided clues about the nature, genome stability, pathogenicity and virulence of these organisms. We compared 15 Corynebacterium genomes, from pathogenic and nonpathogenic species, focusing on DNA repair genes. DNA repair is a mechanism of great importance in the maintenance of the genomic stability of any organism; inefficiency of this system can promote genomic instability and lead to death. This vulnerability makes it an interesting target in the study of means to control infectious organisms. We found that nucleotide excision repair (NER) was the only pathway whose involved genes were found in all species, suggesting that DNA integrity can be primarily maintained by NER. Recombination repair (RR) is also a well conserved pathway and most RR genes exist commonly in Corynebacterium spp. Absence of recCD genes was also shared by all species, contributing to prevent genome inversions and favoring genomic stability. Mismatch repair (MMR) appeared to be missing, although some genes in this pathway, such mutT, mutY and mutL, are present. Base excision repair (BER) and direct repair pathways are not conserved pathways, since the genes are not shared by all members; however, the existence of some seems to be enough to ensure pathway activity. An interesting fact is the persistence/acquisition of some repair genes in some species, suggesting an important role in DNA maintenance and evolution. These genes can be important targets in the investigation of the role of DNA repair in the pathogenicity of Corynebacterium species and be used as targets in therapeutic intervention. Phylogenetic analysis of uvrABC NER genes showed a pattern of clusters, in which most groups remained fixed. In general, the presence or inexistence of repair genes was shared by all the species we analyzed, and the loss or acquisition of certain DNA repair genes seems to have been an ancestral event.


Assuntos
Corynebacterium/genética , Reparo do DNA/genética , Modelos Genéticos , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Dano ao DNA/genética , Reparo de Erro de Pareamento de DNA/genética , Genes Bacterianos/genética , Filogenia , Recombinação Genética
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