Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 147
Filtrar
Mais filtros

Base de dados
Tipo de documento
Intervalo de ano de publicação
1.
PLoS Pathog ; 18(9): e1010760, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36048802

RESUMO

The impact of artificial intelligence (AI) in understanding biological processes is potentially immense. Structural elucidation of mycobacterial PE_PGRS is sustenance to unveil the role of these enigmatic proteins. We propose a PGRS "sailing" model as a smart tool to diffuse along the mycomembrane, to expose structural motifs for host interactions, and/or to ship functional protein modules at their C-terminus.


Assuntos
Antígenos de Bactérias , Mycobacterium tuberculosis , Antígenos de Bactérias/metabolismo , Inteligência Artificial , Proteínas de Bactérias/metabolismo , Parede Celular/metabolismo , Mycobacterium tuberculosis/metabolismo
2.
J Immunol ; 206(10): 2420-2429, 2021 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-33941660

RESUMO

We have recently shown that type 2 transglutaminase (TG2) plays a key role in the host's inflammatory response during bacterial infections. In this study, we investigated whether the enzyme is involved in the regulation of the STING pathway, which is the main signaling activated in the presence of both self- and pathogen DNA in the cytoplasm, leading to type I IFN (IFN I) production. In this study, we demonstrated that TG2 negatively regulates STING signaling by impairing IRF3 phosphorylation in bone marrow-derived macrophages, isolated from wild-type and TG2 knockout mice. In the absence of TG2, we found an increase in the IFN-ß production and in the downstream JAK/STAT pathway activation. Interestingly, proteomic analysis revealed that TG2 interacts with TBK1, affecting its interactome composition. Indeed, TG2 ablation facilitates the TBK1-IRF3 interaction, thus indicating that the enzyme plays a negative regulatory effect on IRF3 recruitment in the STING/TBK1 complex. In keeping with these findings, we observed an increase in the IFNß production in bronchoalveolar lavage fluids from COVID-19-positive dead patients paralleled by a dramatic decrease of the TG2 expression in the lung pneumocytes. Taken together, these results suggest that TG2 plays a negative regulation on the IFN-ß production associated with the innate immunity response to the cytosolic presence of both self- and pathogen DNA.


Assuntos
COVID-19/imunologia , Proteínas de Ligação ao GTP/imunologia , Imunidade Inata , Fator Regulador 3 de Interferon/imunologia , Proteínas de Membrana/imunologia , Proteínas Serina-Treonina Quinases/imunologia , SARS-CoV-2/imunologia , Transdução de Sinais/imunologia , Transglutaminases/imunologia , Animais , COVID-19/genética , COVID-19/patologia , Proteínas de Ligação ao GTP/genética , Humanos , Fator Regulador 3 de Interferon/genética , Interferon beta/genética , Interferon beta/imunologia , Proteínas de Membrana/genética , Camundongos , Camundongos Knockout , Proteína 2 Glutamina gama-Glutamiltransferase , Proteínas Serina-Treonina Quinases/genética , Transdução de Sinais/genética , Transglutaminases/genética
3.
Eur J Pediatr ; 182(5): 2155-2167, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36847873

RESUMO

Commercially available Interferon-γ release assays (IGRAs), including the last-generation QuantiFERON TB-Plus (QFT-Plus), are effective in aiding the diagnosis of tuberculosis (TB) infection but cannot distinguish latent TB subjects from active TB patients. The aim of this study was to prospectively evaluate the performance of an HBHA-based IGRA, combined with commercially available IGRAs, to assess their usefulness as a prognostic biomarkers and aid in the monitoring of TB treatment in children. Following clinical, microbiological, and radiological assessment, children younger than 18 years of age classified as either LTBI or active TB were tested at baseline and during treatment by the QuantiFERON TB-Plus (QFT) assay and an aliquot of whole-blood was stimulated with HBHA. Among the 655 children evaluated, 559 (85.3%) were classified as "Non TB", 44 patients (6.7%) with active TB, and 52 (7.9%) with LTBI. The median HBHA-IGRA IFN-gamma responses were able to discriminate active TB from LTBI (0.13 IU/ml vs 1.995, (p < 0,0001), those with asymptomatic TB from those with symptomatic TB (1.01 IU/ml vs 0.115 IU/ml, p 0.017), or more severe TB (p 0.022), and significantly raised during successful TB treatment (p < 0.0001). Conversely, CD4 + and CD8 + responses were similar in all groups of patients, although active TB patients had higher CD4 + responses and LTBI higher CD8 + responses.  Conclusion: HBHA-based IGRA, combined with CD4 + and CD8 + responses assessed by commercially available IGRAs, is a useful support in the characterization of the TB spectrum in children and monitoring of TB-therapy. What is Known: • Current immune diagnostics are not able to discriminate active and latent Ttuberculosis, including the recently approved QFT-PLUS.. • New immunological assays with prognostic value are highly needed. What is New: • HBHA-based IGRA, combined with CD4+ and CD8+ responses assessed by commercially available IGRAs, is a useful support for the differentiation of active and latent TB in children.. • HBHA-based IGRA, combined with CD4+ and CD8+ responses assessed by commercially available IGRAs, is a useful support in the monitoring of TBtherapy in children..


Assuntos
Tuberculose Latente , Mycobacterium tuberculosis , Tuberculose , Criança , Humanos , Linfócitos T CD8-Positivos , Interferon gama , Testes de Liberação de Interferon-gama , Tuberculose Latente/diagnóstico , Tuberculose Latente/tratamento farmacológico , Teste Tuberculínico , Tuberculose/diagnóstico , Tuberculose/tratamento farmacológico
4.
Acta Paediatr ; 112(11): 2418-2425, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37540888

RESUMO

AIM: Higher number of monocytes and neutrophils may correlate with active tuberculosis (TB) in children. However, the few paediatric studies available are limited by the small numbers of children with TB disease or infection included. METHODS: We calculated the monocyte-to-lymphocyte-ratio (MLR), neutrophil-to-lymphocyte-ratio (NLR) and neutrophil-to-monocyte-plus-lymphocyte-ratio (NMLR) in children with active TB, latent TB infection (LTBI), other infectious and non-infectious conditions and healthy children evaluated in two referral centres in Rome. RESULTS: Overall, 649 children were included (41.8% females, mean age of 5.74 years). MLR, NLR and NMLR values were always significantly higher in patients with TB compared with the other groups (p < 0.001). Considering the entire population with the outcome of TB diagnosis, NMLR, with a cut-off of 1.2, had a sensitivity of 63% and a specificity of 76% (AUC: 0.71 [0.64-0.78]); NLR, with a cut-off of 1.5, had a sensitivity of 61% and a specificity of 79% (AUC: 0.72 [0.65-0.79]); MLR, considering a cut-off of 0.2, was less sensitive (56%) but more specific (82%) with a similar AUC (0.72 [0.65-0.79]). CONCLUSION: Our study provides further evidence that MLR, NLR and NMLR can serve as first level diagnostics to support the clinical suspicion of TB in children.


Assuntos
Tuberculose Latente , Tuberculose , Feminino , Humanos , Criança , Pré-Escolar , Masculino , Neutrófilos , Monócitos , Linfócitos , Tuberculose/diagnóstico , Estudos Retrospectivos , Prognóstico
5.
Int J Mol Sci ; 24(2)2023 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-36674717

RESUMO

Host-directed therapies are emerging as a promising tool in the curing of difficult-to-treat infections, such as those caused by drug-resistant bacteria. In this study, we aim to test the potential activity of the FDA- and EMA-approved drugs cysteamine and cystamine against Mycobacterium abscessus. In human macrophages (differentiated THP-1 cells), these drugs restricted M. abscessus growth similar to that achieved by amikacin. Here, we use the human ex vivo granuloma-like structures (GLS) model of infection with the M. abscessus rough (MAB-R) and smooth (MAB-S) variants to study the activity of new therapies against M. abscessus. We demonstrate that cysteamine and cystamine show a decrease in the number of total GLSs per well in the MAB-S and MAB-R infected human peripheral blood mononuclear cells (PBMCs). Furthermore, combined administration of cysteamine or cystamine with amikacin resulted in enhanced activity against the two M. abscessus morpho variants compared to treatment with amikacin only. Treatment with cysteamine and cystamine was more effective in reducing GLS size and bacterial load during MAB-S infection compared with MAB-R infection. Moreover, treatment with these two drugs drastically quenched the exuberant proinflammatory response triggered by the MAB-R variant. These findings showing the activity of cysteamine and cystamine against the R and S M. abscessus morphotypes support the use of these drugs as novel host-directed therapies against M. abscessus infections.


Assuntos
Infecções por Mycobacterium não Tuberculosas , Mycobacterium abscessus , Humanos , Amicacina/farmacologia , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Cisteamina/farmacologia , Cisteamina/uso terapêutico , Cistamina/farmacologia , Cistamina/uso terapêutico , Leucócitos Mononucleares , Infecções por Mycobacterium não Tuberculosas/tratamento farmacológico , Infecções por Mycobacterium não Tuberculosas/microbiologia , Testes de Sensibilidade Microbiana
6.
Carbon N Y ; 194: 34-41, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35313599

RESUMO

Additive manufacturing has played a crucial role in the COVID-19 global emergency allowing for rapid production of medical devices, indispensable tools for hospitals, or personal protection equipment. However, medical devices, especially in nosocomial environments, represent high touch surfaces prone to viral infection and currently used filaments for 3D printing can't inhibit transmission of virus [1]. Graphene-family materials are capable of reinforcing mechanical, optical and thermal properties of 3D printed constructs. In particular, graphene can adsorb near-infrared light with high efficiency. Here we demonstrate that the addition of graphene nanoplatelets to PLA filaments (PLA-G) allows the creation of 3D-printed devices that can be sterilized by near-infrared light exposure at power density analog to sunlight. This method has been used to kill SARS-CoV-2 viral particles on the surface of 3D printed PLA-G by 3 min of exposure. 3D-printed PLA-G is highly biocompatible and can represent the ideal material for the production of sterilizable personal protective equipment and daily life objects intended for multiple users.

7.
Int J Med Microbiol ; 311(4): 151506, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33906074

RESUMO

Isoniazid (INH) is the cornerstone of the anti-tuberculosis regimens and emergence of Mycobacterium tuberculosis (Mtb) resistant strains is a major threat to our ability to control tuberculosis (TB) at global level. Mutations in the gene coding the catalase KatG confer resistance to high level of INH. In this paper, we describe for the first time a complete deletion of the genomic region containing the katG gene in an Mtb clinical strain isolated in Italy in a patient with HIV infection that previously completed INH preventive therapy. We genotypically characterized the Mtb strain and showed that katG deletion confers high-level resistance to INH (MIC > 25.6 µg/mL). The katG deletion did not impact significantly on Mtb fitness as we did not detect enhanced susceptibility to H2O2 compared to the wild type Mtb strains nor impaired growth in in vitro infection models. These findings highlight the ability of Mtb to acquire resistance to INH while maintaining fitness and pathogenic potential.


Assuntos
Infecções por HIV , Mycobacterium tuberculosis , Antituberculosos/farmacologia , Antituberculosos/uso terapêutico , Proteínas de Bactérias/genética , Farmacorresistência Bacteriana/genética , Deleção de Genes , Humanos , Peróxido de Hidrogênio , Itália , Testes de Sensibilidade Microbiana , Mutação , Mycobacterium tuberculosis/genética
8.
Am J Respir Cell Mol Biol ; 62(4): 430-439, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31697586

RESUMO

We investigated the contribution of human leukocyte antigen A2 (HLA-A2) and HLA-E-restricted CD8+ T cells in patients with Mycobacterium tuberculosis and human immunodeficiency virus 1 (HIV-1) coinfection. HIV-1 downregulates HLA-A, -B, and -C molecules in infected cells, thus influencing recognition by HLA class I-restricted CD8+ T cells but not by HLA-E-restricted CD8+ T cells, owing to the inability of the virus to downmodulate their expression. Therefore, antigen-specific HLA-E-restricted CD8+ T cells could play a protective role in Mycobacterium tuberculosis and HIV-1 coinfection. HLA-E- and HLA-A2-restricted Mycobacterium tuberculosis-specific CD8+ T cells were tested in vitro for cytotoxic and microbicidal activities, and their frequencies and phenotypes were evaluated ex vivo in patients with active tuberculosis and concomitant HIV-1 infection. HIV-1 and Mycobacterium tuberculosis coinfection caused downmodulation of HLA-A2 expression in human monocyte-derived macrophages associated with resistance to lysis by HLA-A2-restricted CD8+ T cells and failure to restrict the growth of intracellular Mycobacterium tuberculosis. Conversely, HLA-E surface expression and HLA-E-restricted cytolytic and microbicidal CD8 responses were not affected. HLA-E-restricted and Mycobacterium tuberculosis-specific CD8+ T cells were expanded in the circulation of patients with Mycobacterium tuberculosis/HIV-1 coinfection, as measured by tetramer staining, but displayed a terminally differentiated and exhausted phenotype that was rescued in vitro by anti-PD-1 (programmed cell death protein 1) monoclonal antibody. Together, these results indicate that HLA-E-restricted and Mycobacterium tuberculosis-specific CD8+ T cells in patients with Mycobacterium tuberculosis/HIV-1 coinfection have an exhausted phenotype and fail to expand in vitro in response to antigen stimulation, which can be restored by blocking the PD-1 pathway using the specific monoclonal antibody nivolumab.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Coinfecção/imunologia , Infecções por HIV/imunologia , HIV-1/imunologia , Antígeno HLA-A2/imunologia , Antígenos de Histocompatibilidade Classe I/imunologia , Mycobacterium tuberculosis/imunologia , Tuberculose/imunologia , Adulto , Antígenos de Bactérias/imunologia , Regulação para Baixo/imunologia , Feminino , Humanos , Ativação Linfocitária/imunologia , Contagem de Linfócitos/métodos , Masculino , Pessoa de Meia-Idade , Antígenos HLA-E
9.
Eur Respir J ; 56(4)2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32586885

RESUMO

Major epidemics, including some that qualify as pandemics, such as severe acute respiratory syndrome (SARS), Middle East respiratory syndrome (MERS), HIV, influenza A (H1N1)pdm/09 and most recently COVID-19, affect the lung. Tuberculosis (TB) remains the top infectious disease killer, but apart from syndemic TB/HIV little is known regarding the interaction of viral epidemics and pandemics with TB. The aim of this consensus-based document is to describe the effects of viral infections resulting in epidemics and pandemics that affect the lung (MERS, SARS, HIV, influenza A (H1N1)pdm/09 and COVID-19) and their interactions with TB. A search of the scientific literature was performed. A writing committee of international experts including the European Centre for Disease Prevention and Control Public Health Emergency (ECDC PHE) team, the World Association for Infectious Diseases and Immunological Disorders (WAidid), the Global Tuberculosis Network (GTN), and members of the European Society of Clinical Microbiology and Infectious Diseases (ESCMID) Study Group for Mycobacterial Infections (ESGMYC) was established. Consensus was achieved after multiple rounds of revisions between the writing committee and a larger expert group. A Delphi process involving the core group of authors (excluding the ECDC PHE team) identified the areas requiring review/consensus, followed by a second round to refine the definitive consensus elements. The epidemiology and immunology of these viral infections and their interactions with TB are discussed with implications for diagnosis, treatment and prevention of airborne infections (infection control, viral containment and workplace safety). This consensus document represents a rapid and comprehensive summary on what is known on the topic.


Assuntos
Infecções Respiratórias/epidemiologia , Tuberculose/epidemiologia , Viroses/epidemiologia , Vacina BCG/uso terapêutico , Betacoronavirus , COVID-19 , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/tratamento farmacológico , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/imunologia , Epidemias , Infecções por HIV/diagnóstico , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , Infecções por HIV/imunologia , Humanos , Vírus da Influenza A Subtipo H1N1 , Influenza Humana/diagnóstico , Influenza Humana/tratamento farmacológico , Influenza Humana/epidemiologia , Influenza Humana/imunologia , Pulmão/imunologia , Coronavírus da Síndrome Respiratória do Oriente Médio , Pandemias , Pneumonia Viral/diagnóstico , Pneumonia Viral/tratamento farmacológico , Pneumonia Viral/epidemiologia , Pneumonia Viral/imunologia , Saúde Pública , Infecções Respiratórias/diagnóstico , Infecções Respiratórias/tratamento farmacológico , Infecções Respiratórias/imunologia , SARS-CoV-2 , Síndrome Respiratória Aguda Grave/diagnóstico , Síndrome Respiratória Aguda Grave/tratamento farmacológico , Síndrome Respiratória Aguda Grave/epidemiologia , Síndrome Respiratória Aguda Grave/imunologia , Tuberculose/diagnóstico , Tuberculose/imunologia , Tuberculose/prevenção & controle , Viroses/diagnóstico , Viroses/tratamento farmacológico , Viroses/imunologia
10.
J Clin Microbiol ; 58(6)2020 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-32229602

RESUMO

Compared to its predecessor QuantiFERON-TB Gold In Tube (QFT-IT), QuantiFERON-TB Gold Plus (QFT-Plus) contains an additional antigen tube (TB2), stimulating both CD4+ and CD8+ T cells. The ability to discriminate CD4+ and CD8+ responses is suggested to be useful in differentiating stages of Mycobacterium tuberculosis infection. While QFT-Plus has already been evaluated in adults, there are not enough data in children evaluated for suspected active tuberculosis (TB) or latent TB infection (LTBI). A prospective cross-sectional study was conducted among children aged 0 to 17 years who were evaluated for suspected active TB or screened for LTBI. All children underwent QFT-Plus and further clinical, radiological, and/or microbiological analyses according to clinical scenario. Of the 198 children enrolled, 43 (21.7%) were tested because of suspicion of active TB. A total of 12/43 (27.9%) were diagnosed with active TB, and among these, 10/12 (83.3%) had a positive QFT-Plus assay. Of the 155 children screened for LTBI, 18 (11.6%) had a positive QFT-Plus, and 5 (2.5%) had an indeterminate result. TB1 and TB2 quantitative responses were not able to discriminate active disease from latent infection. The percent agreement between TB1 and TB2 was 100%. QFT-Plus assay showed good sensitivity for active TB and was particularly useful for the evaluation of children with suspected LTBI, giving a low rate of indeterminate results in this group. More studies are needed to properly evaluate QFT-Plus ability in discriminating active disease from latent infection.


Assuntos
Tuberculose Latente , Mycobacterium tuberculosis , Tuberculose , Adulto , Linfócitos T CD8-Positivos , Criança , Estudos Transversais , Humanos , Testes de Liberação de Interferon-gama , Tuberculose Latente/diagnóstico , Estudos Prospectivos , Teste Tuberculínico , Tuberculose/diagnóstico
11.
Int J Med Microbiol ; 309(5): 299-306, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31147175

RESUMO

Interferon-γ inducible protein 10 (IP-10), is a potent chemoattractant that promotes migration of monocytes and activated T-cells to inflammation foci. IP-10 is elevated in serum of patients with chronic hepatitis C virus (HCV) and tuberculosis (TB) infections, although it remains to be determined the contribution of IP-10 in restricting Mycobacterium tuberculosis (Mtb) replication. Here, we investigated the impact of IP-10 on mycobacteria replication using the ex vivo model of human whole-blood (WB) assay. In particular, we compared the levels of IP-10 upon infection with different Mtb clinical strains and species of non-tuberculous mycobacteria (NTM) and evaluated how IP-10 may contain bacterial replication. Interestingly, we observed that the inhibition of the host enzyme dipeptidyl peptidase IV (DPP-IV), which inactivates IP-10 through cleavage of two amino acids at the chemokine N-terminus, restricted mycobacterial persistence in WB, supporting the critical role of full length IP-10 in mediating an anti-Mtb response. Addition of recombinant IP-10 expressed in eukaryotic cells enhanced the anti-mycobacterial activity in WB, although no differences were observed when IP-10 containing different proportions of cleaved and non-cleaved forms of the chemokine were added. Moreover, recombinant IP-10 did not exert a direct anti-mycobacterial effect. Our results underscore the clinical relevance of IP-10 in mycobacteria pathogenesis and support the potential outcomes that may derive by targeting the IP-10/CXCR3 pathway as host directed therapies for the treatment of Mtb or NTM infections.


Assuntos
Células Sanguíneas/microbiologia , Quimiocina CXCL10/imunologia , Mycobacterium tuberculosis/crescimento & desenvolvimento , Adulto , Bioensaio , Humanos , Masculino , Micobactérias não Tuberculosas/crescimento & desenvolvimento , Tuberculose/microbiologia , Células Tumorais Cultivadas
12.
Cell Microbiol ; 20(12): e12952, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30192424

RESUMO

PE_PGRSs of Mycobacterium tuberculosis (Mtb) represent a family of complex and peculiar proteins whose role and function remain elusive. In this study, we investigated PE_PGRS3 and PE_PGRS4, two highly homologous PE_PGRSs encoded by two contiguous genes in the Mtb genome. Using a gene-reporter system in Mycobacterium smegmatis (Ms) and transcriptional analysis in Mtb, we show that PE_PGRS3, but not PE_PGRS4, is specifically expressed under low phosphate concentrations. Interestingly, PE_PGRS3, but not PE_PGRS4, has a unique, arginine-rich C-terminal domain of unknown function. Heterologous expression of PE_PGRS3 in Ms was used to demonstrate cellular localisation of the protein on the mycobacterial surface, where it significantly affects net surface charge. Moreover, expression of full-length PE_PGRS3 enhanced adhesion of Ms to murine macrophages and human epithelial cells and improved bacterial persistence in spleen tissue following infection in mice. Expression of the PE_PGRS3 functional deletion mutant lacking the C-terminal domain in Ms did not enhance adhesion to host cells, showing a phenotype similar to the Ms parental strain. Interestingly, enhanced persistence of Ms expressing PE_PGRS3 did not correlate with increased concentrations of inflammatory cytokines. These results point to a critical role for the ≈ 80 amino acids long, arginine-rich C-terminal domain of PE_PGRS3 in tuberculosis pathogenesis.


Assuntos
Proteínas de Bactérias/genética , Mycobacterium smegmatis/genética , Fosfatos/farmacologia , Células A549 , Animais , Aderência Bacteriana/fisiologia , Proteínas de Bactérias/metabolismo , Membrana Celular/metabolismo , Citocinas/metabolismo , Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos , Interações Hospedeiro-Patógeno/fisiologia , Humanos , Macrófagos/microbiologia , Camundongos Endogâmicos C57BL , Microrganismos Geneticamente Modificados , Infecções por Mycobacterium não Tuberculosas/microbiologia , Mycobacterium smegmatis/patogenicidade , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/genética , Fosfatos/administração & dosagem , Domínios Proteicos , Baço/microbiologia
13.
Molecules ; 24(23)2019 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-31795400

RESUMO

Tuberculosis (TB) is one of the top 10 causes of death worldwide. This scenario is further complicated by the insurgence of multidrug-resistant (MDR) and extensively drug-resistant (XDR) TB. The identification of appropriate drugs with multi-target affinity profiles is considered to be a widely accepted strategy to overcome the rapid development of resistance. The aim of this study was to discover Food and Drug Administration (FDA)-approved drugs possessing antimycobacterial activity, potentially coupled to an effective multi-target profile. An integrated screening platform was implemented based on computational procedures (high-throughput docking techniques on the target enzymes peptide deformylase and Zmp1) and in vitro phenotypic screening assays using two models to evaluate the activity of the selected drugs against Mycobacterium tuberculosis (Mtb), namely, growth of Mtb H37Rv and of two clinical isolates in axenic media, and infection of peripheral blood mononuclear cells with Mtb. Starting from over 3000 FDA-approved drugs, we selected 29 marketed drugs for submission to biological evaluation. Out of 29 drugs selected, 20 showed antimycobacterial activity. Further characterization suggested that five drugs possessed promising profiles for further studies. Following a repurposing strategy, by combining computational and biological efforts, we identified marketed drugs with relevant antimycobacterial profiles.


Assuntos
Antituberculosos , Reposicionamento de Medicamentos , Leucócitos Mononucleares/microbiologia , Mycobacterium tuberculosis/crescimento & desenvolvimento , Tuberculose/tratamento farmacológico , Antituberculosos/química , Antituberculosos/farmacologia , Aprovação de Drogas , Avaliação Pré-Clínica de Medicamentos , Humanos , Leucócitos Mononucleares/metabolismo , Leucócitos Mononucleares/patologia , Tuberculose/metabolismo , Tuberculose/patologia
14.
Infection ; 46(5): 591-597, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29687315

RESUMO

PURPOSE: Mycobacterium abscessus, and rapidly growing mycobacteria in general, are rare but increasing causes of central nervous system (CNS) infections. The aim of this study is to highlight the importance of considering these microorganism in the differential diagnosis of CNS infections, obtaining a prompt diagnosis, and improving clinical outcomes. METHODS: Case report and literature review. RESULTS: We report a case of meningeal infection in a patient who underwent decompressive craniectomy after a craniofacial trauma. The diagnosis was made analyzing a sample obtained during a second operation of cranioplasty. A regimen of amikacin, clarithromycin, and imipenem/cilastatin was started. In the following days, the patient experienced a variety of side effects. So, first clarithromycin was replaced with linezolid, then amikacin was stopped and cefoxitin added to the therapy and at the end all the antibiotics were withdrawn. The patient was discharged in good conditions and a clinical interdisciplinary follow-up was started. After 12 months, the patient is still doing well. After a literature analysis, 15 cases of M. abscessus CNS infections were identified. Various modes of acquisition, underlying disease and therapeutic schemes were evident. CONCLUSIONS: Considering the results of the literature analysis and the increasing incidence of M. abscessus, all specialists involved in the management of CNS infection should be aware of the importance of atypical microorganisms in differential diagnosis.


Assuntos
Achados Incidentais , Infecções por Mycobacterium não Tuberculosas/diagnóstico , Mycobacterium abscessus , Tuberculose Meníngea/diagnóstico , Proteínas de Bactérias/genética , Chaperonina 60/genética , Escala de Coma de Glasgow , Hematoma Subdural Agudo/complicações , Hematoma Subdural Agudo/diagnóstico , Humanos , Período Intraoperatório , Masculino , Pessoa de Meia-Idade , Infecções por Mycobacterium não Tuberculosas/complicações , Infecções por Mycobacterium não Tuberculosas/microbiologia , Mycobacterium abscessus/genética , Reação em Cadeia da Polimerase , Tomografia Computadorizada por Raios X , Tuberculose Meníngea/complicações , Tuberculose Meníngea/microbiologia
15.
Chemotherapy ; 63(3): 172-180, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30032143

RESUMO

The emergence and spread of drug-resistant strains of Mycobacterium tuberculosis is worsening the global threat of tuberculosis (TB). There is a need and urgency for the development of new treatments for TB, for the management of drug resistant TB (MDR-TB) and for improved regimens against drug-susceptible TB, with the goal of reducing toxicity and length of therapy that will boost patience compliance. The paucity of new drugs is a major obstacle to design new regimens while host-directed therapies (HDTs) are emerging as a promising area of research and are opening new avenues to fight TB. In this review, we discuss examples of potentially promising strategies aimed at improving the host response to M. tuberculosis, and argue how a better understanding of TB pathogenesis, with the fine characterization of the immunological mediators involved, may pave the way for the design of new therapies, the identification of new drugs or the repurposing of some already in use for other diseases. We emphasize that any HDTs shall be included as adjunct therapy to the drug-combination regimens already in use for TB, with the goal to reduce tissue damage and immunopathology and enhance bacterial clearance. We anticipate that the benefits of HDTs against TB will be highest against MDR-TB, where the activity of current regimens is poor and the cost high.


Assuntos
Antituberculosos/uso terapêutico , Tuberculose/tratamento farmacológico , Antituberculosos/farmacologia , Autofagia/efeitos dos fármacos , Humanos , Hospedeiro Imunocomprometido , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/isolamento & purificação , Tuberculose/imunologia , Tuberculose/patologia , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Tuberculose Resistente a Múltiplos Medicamentos/patologia
16.
Chemotherapy ; 63(3): 148-154, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29902788

RESUMO

BACKGROUND: The presence in a geographic area of Mycobacterium tuberculosis (Mtb) strains belonging to different phylogeographic lineages and showing different drug susceptibility patterns may suggest recent transmission, with implications in terms of patient clinical management and disease control. The aim of this study was to carry out a preliminary epidemiological investigation of tuberculosis (TB) cases in Rome. METHODS: A total of 232 Mtb isolates, collected from new or previously treated patients, admitted between 2008 and 2014 at 2 hospital settings in Rome with a diagnosis of TB, were analyzed by spoligotyping and analyzing 24 variable-number tandem repeats (VNTR) mycobacterial interspersed repetitive-unit (MIRU) loci. The SITVIT2 database and the MIRU-VNTRplus web applications were used to identify the strain genotypes and to generate phylogenetic trees. RESULTS: Based on the position on the phylogenetic tree, 97.4% of the strains were associated with 1 of the 7 main lineages. The Euro-American lineage was the most commonly represented (81.9%) within both Italian and foreign-born populations, although all main lineages were present. The highest frequency of drug-resistant strains was found among the East-Asian lineage (Beijing genotype) isolated from foreign-born patients. CONCLUSIONS: Dynamics of TB transmission in Rome indicate recent spread of Mtb strains belonging to phylogeographic lineages and clades usually found in countries and geographic areas with a high incidence of TB, similarly to what is observed in most metropolitan areas in Western Europe. Knowledge from molecular and classical epidemiology provides an important tool for disease control.


Assuntos
Variação Genética , Mycobacterium tuberculosis/genética , Tuberculose/diagnóstico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , DNA Bacteriano/isolamento & purificação , DNA Bacteriano/metabolismo , Feminino , Genótipo , Humanos , Lactente , Itália , Masculino , Pessoa de Meia-Idade , Mycobacterium tuberculosis/classificação , Mycobacterium tuberculosis/isolamento & purificação , Filogenia , Sequências de Repetição em Tandem/genética , Tuberculose/microbiologia , Adulto Jovem
17.
Fetal Pediatr Pathol ; 37(5): 337-347, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30260729

RESUMO

BACKGROUND: Growing evidence suggests that vitamin D deficiency might be implicated in the development of active tuberculosis (TB). We evaluated vitamin D levels in children with active TB compared to children with latent TB infection (LTBI), non-TB pneumonia (NTBP) and healthy controls to determine if there was a difference. METHODS: In this prospective study, vitamin D levels were measured and compared between the four groups and adjusted for age, ethnicity, gender and season of sample collection. RESULTS: Fifty-seven children were included: 24.6% active TB, 28.1% LTBI, 22.8% NPTB and 24.6% healthy controls. 36.8% of all children tested had an insufficient or deficient vitamin D level. Vitamin D level was significantly lower in active TB compared to other groups (p = 0.004). CONCLUSIONS: Our study showed a correlation between hypovitaminosis D and active pulmonary TB.


Assuntos
Tuberculose Latente/sangue , Pneumonia/sangue , Tuberculose/sangue , Deficiência de Vitamina D/epidemiologia , Vitamina D/sangue , Estudos de Casos e Controles , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Deficiência de Vitamina D/sangue , Deficiência de Vitamina D/complicações
18.
Adv Exp Med Biol ; 1019: 191-207, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29116636

RESUMO

PE and PPE are two large families of proteins typical of mycobacteria whose structural genes in the Mycobacterium tuberculosis complex (MTBC) occupy about 7% of the total genome. The most ancestral PE and PPE proteins are expressed by genes that belong to the same operon and in most cases are found inserted in the esx clusters, encoding a type VII secretion system. Duplication and expansion of pe and ppe genes, coupled with intragenomic and intergenomic recombination events, led to the emergence of the polymorphic pe_pgrs and ppe_mptr genes in the MTBC genome. The role and function of these proteins, and particularly of the polymorphic subfamilies, remains elusive, although it is widely accepted that PE and PPE proteins may represent a specialized collection used by MTBC to interact with the complex host immune system of mammals. In this chapter, we summarize what has been discovered since the identification of these genes in 1998, focusing on M. tuberculosis genetic variability, host-pathogen interaction and TB pathogenesis.


Assuntos
Variação Antigênica , Antígenos de Bactérias/imunologia , Proteínas de Bactérias/imunologia , Esterases/imunologia , Regulação Bacteriana da Expressão Gênica/imunologia , Genoma Bacteriano , Mycobacterium tuberculosis/imunologia , Imunidade Adaptativa , Antígenos de Bactérias/genética , Proteínas de Bactérias/genética , Sequência Conservada , Esterases/genética , Interações Hospedeiro-Patógeno , Humanos , Imunidade Inata , Família Multigênica , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/crescimento & desenvolvimento , Óperon , Tuberculose/genética , Tuberculose/imunologia , Tuberculose/microbiologia , Sistemas de Secreção Tipo VII/genética , Sistemas de Secreção Tipo VII/imunologia
19.
J Clin Microbiol ; 54(1): 59-63, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26491178

RESUMO

The rapid diagnosis of tuberculosis (TB) and the detection of drug-resistant Mycobacterium tuberculosis strains are critical for successful public health interventions. Therefore, TB diagnosis requires the availability of diagnostic tools that allow the rapid detection of M. tuberculosis and drug resistance in clinical samples. Here, we performed a multicenter study to evaluate the performance of the Seegene Anyplex MTB/NTM MDR-TB assay, a new molecular method based on a multiplex real-time PCR system, for detection of Mycobacterium tuberculosis complex (MTBC), nontuberculous mycobacteria (NTM), and genetic determinants of drug resistance. In total, the results for 755 samples (534 pulmonary and 221 extrapulmonary samples) were compared with the results of smears and cultures. For pulmonary specimens, the sensitivities of the Anyplex assay and acid-fast bacillus smear testing were 86.4% and 75.0%, respectively, and the specificities were 99% and 99.4%. For extrapulmonary specimens, the sensitivities of the Anyplex assay and acid-fast bacillus smear testing were 83.3% and 50.0%, respectively, and the specificities of both were 100%. The negative and positive predictive values of the Anyplex assay for pulmonary specimens were 97% and 100%, respectively, and those for extrapulmonary specimens were 84.6% and 100%. The sensitivities of the Anyplex assay for detecting isoniazid resistance in MTBC strains from pulmonary and extrapulmonary specimens were 83.3% and 50%, respectively, while the specificities were 100% for both specimen types. These results demonstrate that the Anyplex MTB/NTM MDR-TB assay is an efficient and rapid method for the diagnosis of pulmonary and extrapulmonary TB and the detection of isoniazid resistance.


Assuntos
Técnicas Bacteriológicas/métodos , Farmacorresistência Bacteriana Múltipla , Técnicas de Diagnóstico Molecular/métodos , Mycobacterium/efeitos dos fármacos , Mycobacterium/isolamento & purificação , Tuberculose Resistente a Múltiplos Medicamentos/diagnóstico , Humanos , Reação em Cadeia da Polimerase Multiplex , Mycobacterium/classificação , Mycobacterium/genética , Valor Preditivo dos Testes , Reação em Cadeia da Polimerase em Tempo Real , Sensibilidade e Especificidade , Fatores de Tempo
20.
Ann Surg Oncol ; 22 Suppl 3: S979-84, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26286196

RESUMO

BACKGROUND: Approximately 1-9 % of all head and neck squamous cell carcinomas are neck metastases from clinically undetectable primary tumors. Human papillomavirus (HPV) and Epstein-Barr virus (EBV) are proven carcinogenic factors that are associated with oropharyngeal squamous cell carcinoma and nasopharyngeal carcinoma, respectively. In the present study, we evaluated the prevalence of these viruses in neck metastases from unknown primary squamous cell carcinoma. METHODS: We evaluated fresh samples from a consecutive series of 22 neck dissections for metastases from unknown primary squamous cell carcinoma obtained between 2010 and 2012 at a single institution. The samples were tested for the presence of HPV E6 and E7 mRNA and EBV DNA. RESULTS: Oncogenic viral infections were detected in 12 cases (54 % total; 2 HPV18, 5 HPV16, 2 EBV infection, and 3 EBV/HPV16 coinfections). The most frequent primarily involved neck level in our series was IIA (70 %), which had the highest prevalence of viral infection (66 %). We did not find any other significant correlations between virus detection and clinicopathologic parameters or prognosis. DISCUSSION: Neck metastasis from unknown primary squamous cell carcinoma could be another virus-related malignancy in the head and neck region, along with nasopharyngeal and oropharyngeal carcinoma. An evaluation of the impact of viral infection on patient prognosis and sensitivities to different treatment modalities could modify our prognostic assessments and treatment planning. Furthermore, virus detection would have a decisive impact on diagnostic/decisional algorithms, especially if detection methods are implemented on cytologic samples (e.g., thin prep).


Assuntos
Carcinoma de Células Escamosas/virologia , Infecções por Vírus Epstein-Barr/complicações , Neoplasias de Cabeça e Pescoço/virologia , Infecções por Papillomavirus/complicações , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/epidemiologia , Carcinoma de Células Escamosas/secundário , Infecções por Vírus Epstein-Barr/epidemiologia , Infecções por Vírus Epstein-Barr/patologia , Feminino , Seguimentos , Neoplasias de Cabeça e Pescoço/epidemiologia , Neoplasias de Cabeça e Pescoço/patologia , Herpesvirus Humano 4/isolamento & purificação , Humanos , Incidência , Itália/epidemiologia , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Estadiamento de Neoplasias , Papillomaviridae/isolamento & purificação , Infecções por Papillomavirus/epidemiologia , Infecções por Papillomavirus/patologia , Prognóstico
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA