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1.
Clin Exp Immunol ; 205(2): 232-245, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33866550

RESUMO

Tuberculosis (TB) is the leading cause of death from a single bacterial infectious agent and is one of the most relevant issues of public health. Another pandemic disease is type II diabetes mellitus (T2D) that is estimated to affect half a billion people in the world. T2D is directly associated with obesity and a sedentary lifestyle and is frequently associated with immunosuppression. Immune dysfunction induced by hyperglycemia increases infection frequency and severity. Thus, in developing countries the T2D/TB co-morbidity is frequent and represents one of the most significant challenges for the health-care systems. Several immunoendocrine abnormalities are occurring during the chronic phase of both diseases, such as high extra-adrenal production of active glucocorticoids (GCs) by the activity of 11-ß-hydroxysteroid dehydrogenase type 1 (11-ßHSD1). 11-ßHSD1 catalyzes the conversion of inactive cortisone to active cortisol or corticosterone in lungs and liver, while 11-ß-hydroxysteroid dehydrogenase type 2 (11-ßHSD2) has the opposite effect. Active GCs have been related to insulin resistance and suppression of Th1 responses, which are deleterious factors in both T2D and TB. The anabolic adrenal hormone dehydroepiandrosterone (DHEA) exerts antagonistic effects on GC signaling in immune cells and metabolic tissues; however, its anabolic effects prohibit its use to treat immunoendocrine diseases. 16α-bromoepiandrosterone (BEA) is a water miscible synthetic sterol related to DHEA that lacks an anabolic effect while amplifying the immune and metabolic properties with important potential therapeutic uses. In this work, we compared the expression of 11-ßHSD1 and the therapeutic efficacy of BEA in diabetic mice infected with tuberculosis (TB) (T2D/TB) with respect to non-diabetic TB-infected mice (TB). T2D was induced by feeding mice with a high-fat diet and administering a single low-dose of streptozotocin. After 4 weeks of T2D establishment, mice were infected intratracheally with a high-dose of Mycobacterium tuberculosis strain H37Rv. Then, mice were treated with BEA three times a week by subcutaneous and intratracheal routes. Infection with TB increased the expression of 11-ßHSD1 and corticosterone in the lungs and liver of both T2D/TB and TB mice; however, T2D/TB mice developed a more severe lung disease than TB mice. In comparison with untreated animals, BEA decreased GC and 11-ßHSD1 expression while increasing 11-ßHSD2 expression. These molecular effects of BEA were associated with a reduction in hyperglycemia and liver steatosis, lower lung bacillary loads and pneumonia. These results uphold BEA as a promising effective therapy for the T2D/TB co-morbidity.


Assuntos
Androsterona/farmacologia , Antituberculosos/farmacologia , Diabetes Mellitus Experimental/tratamento farmacológico , Hipoglicemiantes/farmacologia , Tuberculose/tratamento farmacológico , 11-beta-Hidroxiesteroide Desidrogenases/metabolismo , Animais , Comorbidade , Corticosterona/farmacologia , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/metabolismo , Modelos Animais de Doenças , Hidrocortisona/metabolismo , Pulmão/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Mycobacterium tuberculosis/efeitos dos fármacos , Tuberculose/metabolismo
3.
J Clin Gastroenterol ; 47(7): 612-20, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23426447

RESUMO

OBJECTIVE: To determine whether bacterial pathogens can be detected within the diseased submucosal tissues of patients with Crohn's disease by molecular techniques independent of cultural methods. DESIGN: We designed a quantitative polymerase chain reaction to detect 32 virulence genes and transposons within submucosal tissues of patients with Crohn's disease and controls and compared the microbiome of the submucosa with mucosal bacterial populations. RESULTS: Within submucosal tissues, the bacterial invasion/adherence genes eaeA and invA were detected in 43% of patients (P=0.01 and 0.008 vs. mucosa and controls, respectively) and the Mycobacterium-specific IS900 and 251F genes detected in 50% of patients (P=0.03 vs. mucosa and controls). These findings were mutually exclusive: invasion/adhesion genes and Mycobacterium-associated transposons were not detected in the same patient. Metagenomic sequencing and quantitative polymerase chain reaction results confirmed effective separation of the submucosal and mucosal microbiome and the existence of a submucosal bacterial population within diseased tissues. CONCLUSIONS: This study is the first to examine the microbial populations of submucosal tissues during intestinal disease and provide evidence of a distinct submucosal microbiome and biotypes within Crohn's disease. These data suggests that Crohn's disease may not be a single disease, but a spectrum that can be divided into distinct biotypes based on the presence of invasion/adherence genes or Mycobacterium-associated transposons. If corroborated by larger population studies, these findings could revolutionize the diagnosis, management, and treatment of Crohn's disease by the identification of patient biotypes and the application of targeted chemotherapeutic treatments that go beyond supportive in nature.


Assuntos
Bactérias/patogenicidade , Doença de Crohn/microbiologia , DNA Bacteriano/análise , Mucosa Intestinal/microbiologia , Adesinas Bacterianas/genética , Adulto , Idoso , Bactérias/genética , Proteínas de Bactérias/genética , Sequência de Bases , Doença de Crohn/classificação , Escherichia coli/genética , Escherichia coli/patogenicidade , Proteínas de Escherichia coli/genética , Feminino , Genoma Bacteriano/genética , Humanos , Masculino , Metagenoma/genética , Pessoa de Meia-Idade , Mycobacterium/genética , Mycobacterium/patogenicidade , Reação em Cadeia da Polimerase em Tempo Real/métodos , Salmonella/genética , Salmonella/patogenicidade , Virulência/genética , Yersinia/genética , Yersinia/patogenicidade , Adulto Jovem
4.
Crit Rev Microbiol ; 38(1): 52-93, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22242906

RESUMO

It has been more than 25 years since Mycobacterium paratuberculosis was first proposed as an etiologic agent in Crohn's disease based on the isolation of this organism from several patients. Since that time, a great deal of information has been accumulated that clearly establishes an association between M. paratuberculosis and Crohn's disease. However, data are conflicting and difficult to interpret and the field has become divided into committed advocates and confirmed skeptics. This review is an attempt to provide a thorough and objective summary of current knowledge from both basic and clinical research from the views and interpretations of both the antagonists and proponents. The reader is left to draw his or her own conclusions related to the validity of the issues and claims made by the opposing views and data interpretations. Whether M. paratuberculosis is a causative agent in some cases or simply represents an incidental association remains a controversial topic, but current evidence suggests that the notion should not be so readily dismissed. Remaining questions that need to be addressed in defining the role of M. paratuberculosis in Crohn's disease and future implications are discussed.


Assuntos
Doença de Crohn/microbiologia , Infecções por Mycobacterium/microbiologia , Mycobacterium avium subsp. paratuberculosis/isolamento & purificação , Doença de Crohn/complicações , Humanos , Infecções por Mycobacterium/complicações , Mycobacterium avium subsp. paratuberculosis/fisiologia
5.
J Clin Gastroenterol ; 46(8): 649-55, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22858515

RESUMO

The relation of Mycobacterium avium ss paratuberculosis (MAP) to Crohn's Disease (CD) and other MAP-associated conditions remains controversial. New data, coupled with the analogous Helicobacter pylori (H. pylori) story, has permitted us to piece together the MAP puzzle and move forward with a more scientific way of treating inflammatory bowel disease, particularly CD. As infection moves centre stage in inflammatory bowel disease, the dated "aberrant reaction" etiology has lost scientific credibility. Now, our growing understanding of MAP-associated diseases demands review and articulation. We focus here on (1) the concept of MAP-associated diseases; (2) causality, Johne Disease, the "aberrant reaction" hypothesis; and (3) responses to published misconceptions questioning MAP as a pathogen in CD.


Assuntos
Doença de Crohn/etiologia , Doença de Crohn/microbiologia , Mycobacterium avium subsp. paratuberculosis/isolamento & purificação , Paratuberculose/complicações , Animais , Bovinos , Humanos , Mycobacterium avium subsp. paratuberculosis/genética , Paratuberculose/microbiologia
6.
Vaccine ; 38(8): 2016-2025, 2020 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-31902643

RESUMO

Studies in cattle show CD8 cytotoxic T cells (CTL), with the ability to kill intracellular bacteria, develop following stimulation of monocyte-depleted peripheral blood mononuclear cells (mdPBMC) with antigen presenting cells (APC, i.e. conventional dendritic cells [cDC] and monocyte-derived DC [MoDC]) pulsed with MMP, a membrane protein from Mycobacterium avium subsp. paratuberculosis (Map) encoded by MAP2121c. CTL activity was diminished if CD4 T cells were depleted from mdPBMC before antigen (Ag) presentation by APC, suggesting simultaneous cognate recognition of MMP epitopes presented by MHC I and MHC II molecules to CD4 and CD8 T cells is essential for development of CTL activity. To explore this possibility, studies were conducted with mdPBMC cultures in the presence of monoclonal antibodies (mAbs) specific for MHC class I and MHC class II molecules. The CTL response of mdPBMC to MMP-pulsed APC was completely blocked in the presence of mAbs to both MHC I and II molecules and also blocked in the presence of mAbs to either MHC I or MHC II alone. The results demonstrate simultaneous cognate recognition of Ag by CD4 and CD8 T cells is essential for delivery of CD4 T cell help to CD8 T cells to elicit development of CTL.


Assuntos
Epitopos/imunologia , Mycobacterium avium subsp. paratuberculosis , Paratuberculose/prevenção & controle , Linfócitos T Citotóxicos/imunologia , Vacinas contra a Tuberculose/imunologia , Animais , Apresentação de Antígeno , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Bovinos , Células Cultivadas , Antígenos de Histocompatibilidade Classe I/imunologia , Antígenos de Histocompatibilidade Classe II/imunologia , Leucócitos Mononucleares/imunologia , Mycobacterium avium subsp. paratuberculosis/imunologia , Vacinas de Subunidades Antigênicas/imunologia
7.
Front Public Health ; 5: 208, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29021977

RESUMO

On March 24 and 25, 2017 researchers and clinicians from around the world met at Temple University in Philadelphia to discuss the current knowledge of Mycobacterium avium ssp. paratuberculosis (MAP) and its relationship to human disease. The conference was held because of shared concern that MAP is a zoonotic bacterium that poses a threat not only to animal health but also human health. In order to further study this problem, the conferees discussed ways to improve MAP diagnostic tests and discussed potential future anti-MAP clinical trials. The conference proceedings may be viewed on the www.Humanpara.org website. A summary of the salient work in this field is followed by recommendations from a majority of the conferees.

9.
PLoS One ; 10(7): e0134382, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26222621

RESUMO

Since Crohn's disease is a transmural disease, we hypothesized that examination of deep submucosal tissues directly involved in the inflammatory disease process may provide unique insights into bacterial populations transgressing intestinal barriers and bacterial populations more representative of the causes and agents of the disease. We performed deep 16s microbiota sequencing on isolated ilea mucosal and submucosal tissues on 20 patients with Crohn's disease and 15 non-inflammatory bowel disease controls with a depth of coverage averaging 81,500 sequences in each of the 70 DNA samples yielding an overall resolution down to 0.0001% of the bacterial population. Of the 4,802,328 total sequences generated, 98.9% or 4,749,183 sequences aligned with the Kingdom Bacteria that clustered into 8545 unique sequences with <3% divergence or operational taxonomic units enabling the identification of 401 genera and 698 tentative bacterial species. There were significant differences in all taxonomic levels between the submucosal microbiota in Crohn's disease compared to controls, including organisms of the Order Desulfovibrionales that were present within the submucosal tissues of most Crohn's disease patients but absent in the control group. A variety of organisms of the Phylum Firmicutes were increased in the subjacent submucosa as compared to the parallel mucosal tissue including Ruminococcus spp., Oscillospira spp., Pseudobutyrivibrio spp., and Tumebacillus spp. In addition, Propionibacterium spp. and Cloacibacterium spp. were increased as well as large increases in Proteobacteria including Parasutterella spp. and Methylobacterium spp. This is the first study to examine the microbial populations within submucosal tissues of patients with Crohn's disease and to compare microbial communities found deep within the submucosal tissues with those present on mucosal surfaces. Our data demonstrate the existence of a distinct submucosal microbiome and ecosystem that is not well reflected in the mucosa and/or downstream fecal material.


Assuntos
Doença de Crohn/microbiologia , Íleo/microbiologia , Mucosa Intestinal/microbiologia , Adulto , Idoso , Bactérias/genética , DNA Bacteriano/genética , Fezes/microbiologia , Feminino , Humanos , Masculino , Microbiota/genética , Pessoa de Meia-Idade , Adulto Jovem
10.
World J Gastroenterol ; 21(13): 4048-62, 2015 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-25852293

RESUMO

A cohort of family members with various chronic diseases including Crohn's disease, asthma, complex regional pain syndrome, hypothyroidism, type 1 diabetes mellitus, and lymphangiomatosis and/or evidence of infection by Mycobacterium avium subsp. paratuberculosis (MAP) are described in this series of case reports. MAP was cultured from the blood of three members affected by the first five diseases and there was accompanying elevated anti-MAP IgG in two members. The patient affected by the sixth disease has a markedly elevated anti-MAP titer. The two patients affected by the first four diseases have been treated with a combination of anti-MAP antibiotics and ultraviolet blood irradiation therapy with resolution of the disease symptomatology and inability to culture MAP in post treatment blood samples. These case reports of patients with MAP infections provide supportive evidence of a pathogenic role of MAP in humans.


Assuntos
Antituberculosos/uso terapêutico , Síndromes da Dor Regional Complexa/terapia , Doença de Crohn/terapia , Mycobacterium avium subsp. paratuberculosis/efeitos dos fármacos , Mycobacterium avium subsp. paratuberculosis/efeitos da radiação , Paratuberculose/terapia , Terapia Ultravioleta/métodos , Adulto , Técnicas Bacteriológicas , Biópsia , Criança , Colonoscopia , Terapia Combinada , Síndromes da Dor Regional Complexa/diagnóstico , Síndromes da Dor Regional Complexa/microbiologia , Doença de Crohn/diagnóstico , Doença de Crohn/microbiologia , Feminino , Humanos , Masculino , Mycobacterium avium subsp. paratuberculosis/isolamento & purificação , Paratuberculose/diagnóstico , Paratuberculose/microbiologia , Paratuberculose/transmissão , Indução de Remissão , Resultado do Tratamento , Adulto Jovem
12.
J Patient Saf ; 9(2): 59-67, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23697981

RESUMO

BACKGROUND: Internal Medicine resident (IMR) physician reporting of patient safety events (PSEs) is suboptimal and may be related to poor attitudes toward reporting. PURPOSE: The objective was to evaluate the impact of a PSE reporting expectation on the rates of reporting among IMRs. METHODS: In this prospective cohort study, IMRs were informed of an expectation to submit 1 or more PSE report per month based on the ACGME core competencies. The PSE reports were collected over 9 months and compared with a 4-month baseline before the expectation. Report quality and IMRs' attitudes were also evaluated. RESULTS: There was a significant and initial increase in the total number of reports. However, the number of IMRs meeting the expectation of 1 or more report per month initially rose but was not sustained over the 9-month observational period. Report quality and IMRs attitudes toward reporting were positive but unchanged over time. CONCLUSIONS: Although a reporting expectation increased the total number of reports, the majority of IMRs did not maintain a 1 or more PSE report per month despite positive attitudes.


Assuntos
Atitude do Pessoal de Saúde , Revelação , Medicina Interna/educação , Internato e Residência , Segurança do Paciente , Feminino , Humanos , Masculino , Avaliação de Programas e Projetos de Saúde , Estudos Prospectivos
13.
Expert Rev Clin Immunol ; 7(6): 751-60, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22014016

RESUMO

Although controversial, the use of properly chosen antibiotics in Crohn's disease appears beneficial. Evidence supporting the use of targeted antibiotic therapy comes in two forms: statistical evidence derived from meta-analyses of multiple formal studies and the documented clinical and endoscopic responses in patients treated with antibiotic combinations outside of formal clinical studies. This article reviews evidence from both categories that support the use of properly chosen antibiotic regimens in treating Crohn's disease, comments on the advantages and disadvantages of antibiotic therapy, and attempts to present a unifying hypothesis related to the role of enteric bacteria, mucosal immunity and antibiotic therapy. Relevant studies identified through a Medline search from 1976 to 2011 were assessed for inclusion by two independent observers who resolved any disagreements by consensus. References from all identified articles and recent review articles were cross-checked to ensure a thorough search. Papers were selected based on scientific merit as to which presented original contributions to the results.


Assuntos
Antibacterianos/uso terapêutico , Doença de Crohn/tratamento farmacológico , Quimioterapia Combinada/métodos , Bactérias/imunologia , Bactérias/patogenicidade , Doença de Crohn/imunologia , Doença de Crohn/microbiologia , Humanos , Imunidade nas Mucosas/efeitos dos fármacos , Intestinos/imunologia , Intestinos/microbiologia , MEDLINE
15.
Expert Rev Clin Immunol ; 6(5): 757-9, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20828283

RESUMO

BIT's 1st Annual World Congress of Immunodiseases and Therapeutics was held in Beijing, China, on 15-17 May 2010. The meeting provided a venue for a wide spectrum of researchers in the basic sciences and clinical areas to present and share their data and ideas. The pervading theme of the meeting dealt with the concept that immune mechanisms underlie most, if not all, medical diseases and therefore the future of medical therapeutics necessitates a greater understanding and corrective manipulation of dysfunctional metabolic and immune pathways. The meeting was well run, educational and enjoyable.


Assuntos
Doenças do Sistema Imunitário/imunologia , Doenças do Sistema Imunitário/terapia , Imunoterapia , Autoimunidade , Pesquisa Biomédica , Desenho de Fármacos , Ensaios de Triagem em Larga Escala , Humanos , Doenças do Sistema Imunitário/diagnóstico , Imunidade Inata , Imunomodulação , Comunicação Interdisciplinar , Esteroides/imunologia , Biologia de Sistemas
18.
Med Sci Monit ; 12(2): RA27-33, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16449960

RESUMO

The most prominent theory describes the Crohn's Syndrome as a dysregulated, inappropriate immune response to otherwise innocuous bowel flora in a genetically susceptible host. The autoimmune theory assumes that a specific infectious agent does not exist. Data from mouse models, impairment of the mucosal epithelial barrier and the influence of gut flora are used to support the autoimmune theory. Critics claim that the dysregulated immune responses are not the primary disorder but secondary to an underlying infection. Two other theories are also consistent with the same data. The immunodeficiency theory hypothesizes that defects in innate immunity leading to compensatory immune processes underlie the Crohn's phenotype and suggests that therapy should stimulate immunity rather than suppress it. The mycobacterial theory proposes that Mycobacterium avium subspecies paratuberculosis is one of the causes of the Crohn's Disease syndrome. Mycobacterial molecules dysregulate immune signaling pathways as part of the organisms'evolved survival strategy. If MAP were to initiate the dysregulated immune response then the necessity to hypothesize that commensal gut flora provide the antigenic stimulus would be moot. Commensal bacteria would be relegated to a secondary role of modifying the immune response rather than occupying the central role of providing the initiating antigens. Critics claim that MAP is merely a secondary invader. The three theories differ primarily by emphasizing different aspects of the same overall process.


Assuntos
Doença de Crohn/etiologia , Modelos Biológicos , Animais , Autoimunidade , Doença de Crohn/genética , Doença de Crohn/imunologia , Doença de Crohn/microbiologia , Humanos , Tolerância Imunológica , Imunidade Inata , Peptídeos e Proteínas de Sinalização Intracelular/genética , Camundongos , Modelos Imunológicos , Mutação , Mycobacterium avium subsp. paratuberculosis/patogenicidade , Proteína Adaptadora de Sinalização NOD2
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