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1.
mBio ; 14(4): e0027223, 2023 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-37382506

RESUMO

Drug-resistant tuberculosis (TB) poses a major threat to global TB control; consequently, there is an urgent need to develop novel anti-TB drugs or strategies. Host-directed therapy (HDT) is emerging as an effective treatment strategy, especially for drug-resistant TB. This study evaluated the effects of berbamine (BBM), a bisbenzylisoquinoline alkaloid, on mycobacterial growth in macrophages. BBM inhibited intracellular Mycobacterium tuberculosis (Mtb) growth by promoting autophagy and silencing ATG5, partially abolishing the inhibitory effect. In addition, BBM increased intracellular reactive oxygen species (ROS), while the antioxidant N-acetyl-L-cysteine (NAC) abolished BBM-induced autophagy and the ability to inhibit Mtb survival. Furthermore, the increased intracellular Ca2+ concentration induced by BBM was regulated by ROS, and BAPTA-AM, an intracellular Ca2+-chelating agent, could block ROS-mediated autophagy and Mtb clearance. Finally, BBM could inhibit the survival of drug-resistant Mtb. Collectively, these findings provide evidence that BBM, a Food and Drug Administration (FDA)-approved drug, could effectively clear drug-sensitive and -resistant Mtb through regulating ROS/Ca2+ axis-mediated autophagy and has potential as an HDT candidate for TB therapy. IMPORTANCE It is urgent to develop novel treatment strategies against drug-resistant TB, and HDT provides a promising approach to fight drug-resistant TB by repurposing old drugs. Our studies demonstrate, for the first time, that BBM, an FDA-approved drug, not only potently inhibits intracellular drug-sensitive Mtb growth but also restricts drug-resistant Mtb by promoting macrophage autophagy. Mechanistically, BBM activates macrophage autophagy by regulating the ROS/Ca2+ axis. In conclusion, BBM could be considered as an HDT candidate and may contribute to improving the outcomes or shortening the treatment course of drug-resistant TB.


Assuntos
Benzilisoquinolinas , Mycobacterium tuberculosis , Tuberculose Resistente a Múltiplos Medicamentos , Humanos , Espécies Reativas de Oxigênio , Macrófagos/microbiologia , Benzilisoquinolinas/farmacologia , Autofagia
2.
Clin Microbiol Infect ; 29(8): 1000-1007, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36921717

RESUMO

BACKGROUND: At the 74th World Health Assembly, the WHO issued a strategy for the prevention and control of several major infectious diseases. To achieve the WHO-initiated targets for these infectious diseases, the elimination of mother-to-child transmission is essential. To date, a systematic review of the global and regional prevalence of infections with relevant mother-to-child transmission and outside the spectrum of congenital infections is lacking. OBJECTIVES: We aimed to systematically review the prevalence of HIV, hepatitis B virus (HBV), hepatitis C virus (HCV), and syphilis in pregnant women. DATA SOURCES: MEDLINE, Embase, The Cochrane Library, Web of Science, China National Knowledge Infrastructure, WanFang database and China Biology Medicine disc database, and five WHO Regional Index Medicus databases. STUDY ELIGIBILITY CRITERIA: Original studies reporting the prevalence of infection or coinfection of HIV, HBV, HCV, and syphilis in pregnant women. METHODS: This systematic review followed the preferred reporting items for systematic reviews and meta-analyses 2020 checklist. We used random-effects models to generate pooled prevalence estimates for each infection. RESULTS: The global pooled prevalence in pregnant women of HIV, HBV, HCV, and syphilis was 2.9% (95% CI, 2.4-3.4%), 4.8% (3.8-5.8%), 1.0% (0.8-1.3%), and 0.8% (0.7-0.9%). The pooled prevalence of HIV, HBV, HCV, and syphilis in low-income countries was higher than the global level (HIV: 5.2% [1.6-10.5%); HBV: 6.6% (5.4-7.9%); HCV: 2.7% (1.6-4.1%); syphilis: 3.3% (2.2-4.6%]). The pooled prevalence of HIV, HBV, HCV, and syphilis in lower-middle-income countries was higher than the global level (HIV: 2.9% [0.8-6.1%]; HBV: 4.9% [3.8-6.1%]; HCV: 2.3% [1.2-3.6%]; syphilis: 1.5% [1.0-2.2%]). CONCLUSIONS: The prevalence of these infections among pregnant women was particularly high in resource-poor settings. The relevance and feasibility of current global practice guidelines for the prevention of mother-to-child transmission of these infections in lower-middle-income countries must be evaluated, including timely access to screening and therapeutics.


Assuntos
Infecções por HIV , Hepatite B , Hepatite C , Sífilis , Feminino , Humanos , Gravidez , Sífilis/epidemiologia , Sífilis/diagnóstico , HIV , Gestantes , Infecções por HIV/diagnóstico , Prevalência , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Hepatite B/epidemiologia , Hepatite B/prevenção & controle , Hepatite C/epidemiologia , Vírus da Hepatite B , Hepacivirus
3.
BMC Microbiol ; 22(1): 249, 2022 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-36253713

RESUMO

BACKGROUND: Tuberculosis (TB) caused by Mycobacterium tuberculosis (M. tb) remains a global health issue. The characterized virulent M. tb H37Rv, avirulent M. tb H37Ra and BCG strains are widely used as reference strains to investigate the mechanism of TB pathogenicity. Here, we attempted to determine metabolomic signatures associated with the Mycobacterial virulence in human macrophages through comparison of metabolite profile in THP-1-derived macrophages following exposure to the M. tb H37Rv, M. tb H37Ra and BCG strains. RESULTS: Our findings revealed remarkably changed metabolites in infected macrophages compared to uninfected macrophages. H37Rv infection specifically induced 247 differentially changed metabolites compared to H37Ra or BCG infection. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis revealed H37Rv specifically induces tryptophan metabolism. Moreover, quantitative PCR (qPCR) results showed that indoleamine 2,3-dioxygenase 1 (IDO1) and tryptophan 2,3-dioxygenase 2 (TDO2) which converts the tryptophan to a series of biologically second metabolites were up-regulated in H37Rv-infected macrophages compared to H37Ra- or BCG-infected macrophages, confirming the result of enhanced tryptophan metabolism induced by H37Rv infection. These findings indicated that targeting tryptophan (Trp) metabolism may be a potential therapeutic strategy for pulmonary TB. CONCLUSIONS: We identified a number of differentially changed metabolites that specifically induced in H37Rv infected macrophages. These signatures may be associated with the Mycobacterial virulence in human macrophages. The present findings provide a better understanding of the host response associated with the virulence of the Mtb strain.


Assuntos
Mycobacterium tuberculosis , Tuberculose , Vacina BCG , Humanos , Indolamina-Pirrol 2,3,-Dioxigenase/genética , Indolamina-Pirrol 2,3,-Dioxigenase/metabolismo , Macrófagos/microbiologia , Metabolômica , Triptofano/metabolismo , Triptofano Oxigenase/metabolismo , Tuberculose/microbiologia
4.
Nat Metab ; 4(3): 359-373, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35288721

RESUMO

Both host genetics and the gut microbiome have important effects on human health, yet how host genetics regulates gut bacteria and further determines disease susceptibility remains unclear. Here, we find that the gut microbiome pattern of participants with active tuberculosis is characterized by a reduction of core species found across healthy individuals, particularly Akkermansia muciniphila. Oral treatment of A. muciniphila or A. muciniphila-mediated palmitoleic acid strongly inhibits tuberculosis infection through epigenetic inhibition of tumour necrosis factor in mice infected with Mycobacterium tuberculosis. We use three independent cohorts comprising 6,512 individuals and identify that the single-nucleotide polymorphism rs2257167 'G' allele of type I interferon receptor 1 (encoded by IFNAR1 in humans) contributes to stronger type I interferon signalling, impaired colonization and abundance of A. muciniphila, reduced palmitoleic acid production, higher levels of tumour necrosis factor, and more severe tuberculosis disease in humans and transgenic mice. Thus, host genetics are critical in modulating the structure and functions of gut microbiome and gut microbial metabolites, which further determine disease susceptibility.


Assuntos
Microbioma Gastrointestinal , Tuberculose , Animais , Suscetibilidade a Doenças , Ácidos Graxos Monoinsaturados , Humanos , Imunidade , Camundongos , Receptor de Interferon alfa e beta , Tuberculose/genética , Fatores de Necrose Tumoral/farmacologia , Verrucomicrobia
5.
BMC Cancer ; 21(1): 567, 2021 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-34006241

RESUMO

BACKGROUND: Primary hepatic neuroendocrine tumors (PH-NETs) are extremely rare and unknown. Because of its rarity, its prognosis features and influencing factors are not well established. METHODS: Data of 140 patients with PH-NETs diagnosed in the SEER database from 1975 to 2016 were collected. The demographics and clinic-pathological features were described. By using propensity-score matching (PSM) analysis, three associated cohorts were selected to describe the malignancy of PH-NETs and univariate analysis was conducted. Then, multivariate Cox analyses were performed and a predicting nomograph was constructed. C-index, receiver operating characteristic (ROC) curve and calibration curves were used to evaluate the predictive value of nomogram. RESULTS: The overall survival outcomes of PH-NETs were superior to hepatocellular carcinoma (HCC) with a mean survival time 30.64 vs 25.11 months (p = 0.052), but inferior to gastrointestinal tract neuroendocrine tumors in situ (GI-NETs in situ) with a mean survival time 30.64 vs 41.62 months (p = 0.017). With reference to gastrointestinal neuroendocrine tumors with liver metastasis (GI-NETs-LM), GI-NETs-LM had better outcomes in short time (1-year survival rate: 64.75% vs 56.43%) but was worse in long time (5-year survival rate: 8. 63% vs 18.57%). Multivariate Cox analyses showed that tumor grade and surgery were two independent factors for prognosis of the patients (p < 0.00). Tumor grade and surgery were used to construct the predicting nomogram. The C-index was 0.79 (95%CI = 0.75-0.83). The area under curve (AUC) values in ROC were 0.868 in 1-year and 0.917 in 3-year survival and the calibration curves showed good consistency. CONCLUSIONS: The overall prognosis PH-NETs is generally favorable, better than HCC and GI-NETs-LM in long term. Preoperative biopsy and complete pathological diagnosis were recommended. Radical surgical intervention including transplantation was the first choice in PH-NETs therapy.


Assuntos
Neoplasias Hepáticas/mortalidade , Tumores Neuroendócrinos/mortalidade , Nomogramas , Adulto , Idoso , Feminino , Seguimentos , Humanos , Estimativa de Kaplan-Meier , Fígado/patologia , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Tumores Neuroendócrinos/diagnóstico , Tumores Neuroendócrinos/patologia , Valor Preditivo dos Testes , Curva ROC , Estudos Retrospectivos , Medição de Risco/métodos , Programa de SEER/estatística & dados numéricos , Taxa de Sobrevida , Adulto Jovem
6.
Chem Commun (Camb) ; 57(31): 3753-3756, 2021 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-33876121

RESUMO

We describe an intracellular enzyme-powered DNA circuit probe with a tunable amplifier for sensitive and selective detection of miRNA. This approach has been successfully applied for in situ miRNA-21 fluorescence imaging in live cells. Also, we used chemicals to elevate the APE1 expression level rendering a tunable amplification strength for more flexible imaging applications.


Assuntos
Sondas de DNA/química , DNA Liase (Sítios Apurínicos ou Apirimidínicos)/química , DNA/química , MicroRNAs/análise , Células A549 , DNA/metabolismo , Sondas de DNA/metabolismo , DNA Liase (Sítios Apurínicos ou Apirimidínicos)/metabolismo , Humanos , Células MCF-7 , MicroRNAs/metabolismo , Imagem Óptica
7.
Thorax ; 75(7): 576-583, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32201389

RESUMO

BACKGROUND: Biomarker-based tests for diagnosing TB currently rely on detecting Mycobacterium tuberculosis (Mtb) antigen-specific cellular responses. While this approach can detect Mtb infection, it is not efficient in diagnosing TB, especially for patients who lack aetiological evidence of the disease. METHODS: We prospectively enrolled three cohorts for our study for a total of 630 subjects, including 160 individuals to screen protein biomarkers of TB, 368 individuals to establish and test the predictive model and 102 individuals for biomarker validation. Whole blood cultures were stimulated with pooled Mtb-peptides or mitogen, and 640 proteins within the culture supernatant were analysed simultaneously using an antibody-based array. Sixteen candidate biomarkers of TB identified during screening were then developed into a custom multiplexed antibody array for biomarker validation. RESULTS: A two-round screening strategy identified eight-protein biomarkers of TB: I-TAC, I-309, MIG, Granulysin, FAP, MEP1B, Furin and LYVE-1. The sensitivity and specificity of the eight-protein biosignature in diagnosing TB were determined for the training (n=276), test (n=92) and prediction (n=102) cohorts. The training cohort had a 100% specificity (95% CI 98% to 100%) and 100% sensitivity (95% CI 96% to 100%) using a random forest algorithm approach by cross-validation. In the test cohort, the specificity and sensitivity were 83% (95% CI 71% to 91%) and 76% (95% CI 56% to 90%), respectively. In the prediction cohort, the specificity was 84% (95% CI 74% to 92%) and the sensitivity was 75% (95% CI 57% to 89%). CONCLUSIONS: An eight-protein biosignature to diagnose TB in a high-burden TB clinical setting was identified.


Assuntos
Citocinas/sangue , Programas de Rastreamento/métodos , Mycobacterium tuberculosis/isolamento & purificação , Tuberculose/diagnóstico , Adulto , Biomarcadores/sangue , Feminino , Seguimentos , Humanos , Masculino , Estudos Prospectivos , Curva ROC , Tuberculose/sangue , Tuberculose/microbiologia
8.
Microbes Infect ; 22(3): 119-126, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31678658

RESUMO

CD4+/CD8+ T cells play a major role in conferring immune protection against tuberculosis (TB), but it remains unknown how the immune responses of CD4+/CD8+ T cells exactly correlate with the clinical variables and disease statuses during anti-TB chemotherapy. To address this, several major immune parameters of CD4+/CD8+ T cells in peripheral blood derived from pulmonary TB patients and healthy volunteers were evaluated. We observed that active TB infection induced lower CD3+ T cell and CD4+ T cell levels but higher CD8+T cell levels, while anti-TB chemotherapy reversed these effects. Also, anti-TB treatment induced enhanced production of IL-2 and IFN-γ but reduced expression of IL-10 and IL-6. Moreover, the dynamic changes of CD3, CD4, and CD8 levels did not show a significant association with sputum smear positivity. However, the frequencies of IL-2+CD4+ or IL-10 + CD4+ T effector subpopulation or IL-1ß production in peripheral blood showed significant difference between patients positive for sputum smear and patients negative for sputum smear after anti-TB treatment. These findings implicated that recovery of Th1/CD8+T cell effector levels might be critical immunological events in pulmonary TB patients after treatment and further suggested the importance of these immunological parameters as potential biomarkers for prediction of TB progress and prognosis.


Assuntos
Antituberculosos/uso terapêutico , Linfócitos T CD8-Positivos/imunologia , Células Th1/imunologia , Tuberculose Pulmonar/tratamento farmacológico , Tuberculose Pulmonar/imunologia , Adulto , Povo Asiático/etnologia , Linfócitos T CD4-Positivos/imunologia , China , Feminino , Humanos , Interferon gama/imunologia , Interleucina-10/imunologia , Interleucina-1beta/sangue , Interleucina-1beta/imunologia , Interleucina-6/imunologia , Masculino , Mycobacterium tuberculosis , Tuberculose Pulmonar/etnologia , Adulto Jovem
9.
BMC Infect Dis ; 19(1): 55, 2019 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-30651075

RESUMO

BACKGROUND: Tuberculosis (TB) remains a major public health concern on a global scale, especially in developing nations. So far, no formal guidelines are available for the diagnosis and treatment of tuberculosis pleurisy. The diagnosis of TB is worsened by the immense difficulty in differential determination of tuberculosis pleural effusion (TPE) and malignant pleural effusion (MPE). The purpose of this investigation is to assess the differential diagnostic efficiencies of the pleural IFN-γ release assay (IGRA) and widely-used biochemical parameters in the distinction analysis of TPE and MPE. METHODS: A cohort of 222 patients with pleural effusion was examined, comprising of 143 TPE and 58 MPE patients. The patients were examined with IGRA, and the widely-used biomarkers in the pleural effusion and peripheral blood. RESULTS: Our results show that the TPE patients have significantly higher M. tuberculosis (Mtb) antigen-specific IFN-γ responses to ESAT-6 protein and peptide pool in the blood compared to MPE patients. TPE patients were also shown to have enriched Mtb antigen-specific IFN-γ responses in pleural effusion than in peripheral blood. Among the widely-used biomarkers, the adenosine deaminase (ADA) and carcinoembryonic antigen (CEA) in pleural effusion were better biomarkers with high sensitivity and specificity to discriminate TPE and MPE. In addition, pleural IGRA could not be affected by the pleural adhesion, and the applications of the pleural IGRA together with ADA and CEA provide a promising approach for the TPE and MPE differential identification. CONCLUSIONS: Our study proposes that the integration of pleural IGRA and ADA, CEA detection could add to more effective diagnosis stratagems in the discernment between TPE and MPE.


Assuntos
Biomarcadores/análise , Interferon gama/análise , Derrame Pleural Maligno/diagnóstico , Derrame Pleural/diagnóstico , Tuberculose Pleural/diagnóstico , Adenosina Desaminase/análise , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Antígeno Carcinoembrionário/análise , Criança , Feminino , Humanos , Interferon gama/sangue , Masculino , Pessoa de Meia-Idade , Derrame Pleural/microbiologia , Sensibilidade e Especificidade
10.
Bioorg Med Chem ; 27(4): 644-654, 2019 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-30642693

RESUMO

Dipeptidyl Peptidase-IV (DPP-4) is a validated therapeutic target for type 2 diabetes. Aiming to interact with both residues Try629 and Lys554 in S2' site, a series of novel uracil derivatives 1a-l and 2a-i incorporating benzoic acid moieties at the N3 position were designed and evaluated for their DPP-4 inhibitory activity. Structure-activity relationships (SAR) study led to the identification of the optimal compound 2b as a potent and selective DPP-4 inhibitor (IC50 = 1.7 nM). Docking study revealed the additional salt bridge formed between the carboxylic acid and primary amine of Lys554 has a key role in the enhancement of the activity. Furthermore, compound 2b exhibited no cytotoxicity in human hepatocyte LO2 cells up to 50 µM. Subsequent in vivo evaluations revealed that the ester of 2b robustly improves the glucose tolerance in normal mice. The overall results have shown that compound 2b has the potential to a safe and efficacious treatment for T2DM.


Assuntos
Benzoatos/uso terapêutico , Inibidores da Dipeptidil Peptidase IV/uso terapêutico , Hipoglicemiantes/farmacologia , Uracila/análogos & derivados , Uracila/uso terapêutico , Animais , Benzoatos/síntese química , Benzoatos/toxicidade , Domínio Catalítico , Linhagem Celular , Dipeptidil Peptidase 4/química , Inibidores da Dipeptidil Peptidase IV/síntese química , Inibidores da Dipeptidil Peptidase IV/toxicidade , Desenho de Fármacos , Teste de Tolerância a Glucose , Humanos , Hipoglicemiantes/síntese química , Hipoglicemiantes/toxicidade , Masculino , Camundongos , Simulação de Acoplamento Molecular , Estrutura Molecular , Relação Estrutura-Atividade , Uracila/toxicidade
11.
Nat Commun ; 8: 14904, 2017 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-28383026

RESUMO

α-amino acids bearing aromatic side chains are important synthetic units in the synthesis of peptides and natural products. Although various ß-C-H arylation methodologies for amino acid derivatives involving the assistance of directing groups have been extensively developed, syntheses that directly employ N-protected amino acids as starting materials remain rare. Herein, we report an N-acetylglycine-enabled Pd-catalysed carboxylate-directed ß-C(sp3)-H arylation of aliphatic acids. In this way, various non-natural amino acids can be directly prepared from phthaloylalanine in one step in good to excellent yields. Furthermore, a series of aliphatic acids have been shown to be amenable to this transformation, affording ß-arylated propionic acid derivatives in moderate to good yields. More importantly, this ligand-enabled direct ß-C(sp3)-H arylation could be easily scaled-up to 10 g under reflux conditions, highlighting the potential utility of this synthetic method.


Assuntos
Alanina/metabolismo , Aminoácidos/metabolismo , Ácidos Carboxílicos/metabolismo , Ácidos Graxos/metabolismo , Glicina/análogos & derivados , Paládio , Peptídeos/síntese química , Alanina/análogos & derivados , Carbono/metabolismo , Catálise , Glicina/metabolismo , Hidrogênio/metabolismo , Ligantes
12.
DNA Cell Biol ; 36(1): 58-66, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27828711

RESUMO

Tuberculosis, an infectious disease caused by Mycobacterium tuberculosis (MTB), is one of the global public health catastrophes. Wnt signaling has recently been identified to exert immunoregulatory functions in a variety of inflammatory and infectious diseases, including tuberculosis. The opposite expression of Wnt5a in human and mice during MTB infection drives us to explore the roles and biological significances of reduced Wnt5a for MTB-treated mice. In our study, the reduction of WNT5A in MTB-treated mice lung tissues or MTB-infected mice bone marrow-derived macrophages (BM-Mø) was in a dose- and time-dependent manner. Then, WNT5A-silenced mice, secreted frizzled-related protein 1 (SFRP1)-overexpressed or -silenced mice BM-Mø, were constructed to regulate Wnt5a levels. When Wnt5a is deficient, MTB-induced increases of pro-inflammatory cytokines (TNF-α, IL-1ß, IL-12, and IL-6) can be markedly attenuated in mice lung tissues or BM-Mø. Besides, external disturbance triggered that Wnt5a lower expression can induce Mø to be M2 phenotype and enhance cell apoptosis of MTB-infected mice BM-Mø. Hence, the reduction of Wnt5a is a tactful strategy adopted by Mø to resistant MTB-induced immune responses and to enhance MTB-induced Mø apoptosis in mice. Our study revealed a new style for Mø to manipulate themselves against MTB infection. Our research identifies that Wnt5a deficiency can regulate inflammatory cytokine secretion, polarization, and apoptosis in MTB-infected Mø.


Assuntos
Apoptose , Citocinas/metabolismo , Macrófagos/citologia , Macrófagos/metabolismo , Mycobacterium tuberculosis/fisiologia , Proteína Wnt-5a/deficiência , Animais , Inativação Gênica , Glicoproteínas/genética , Inflamação/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular , Macrófagos/microbiologia , Camundongos , Camundongos Endogâmicos C57BL , Proteína Wnt-5a/genética
13.
Biochem Biophys Res Commun ; 477(2): 167-73, 2016 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-27291149

RESUMO

Tuberculosis (TB) is a serious disease that is characterized by Mycobacterium tuberculosis (M.tb)-triggered immune system impairment and lung tissue damage shows limited treatment options. MicroRNAs (miRNAs) are regulators of gene expression that play critical roles in many human diseases, and can be up- or downregulated by M.tb infection in macrophage. Recently, tissue inhibitor of matrix metalloproteinase (TIMP) 3 has been found to play roles in regulating macrophage inflammation. Here, we found that TIMP3 expression was regulated by miR-206 in M.tb-infected THP-1 human macrophages. In THP-1 cells infected with M.tb, the miR-206 level was significantly upregulated and the expression of TIMP3 was markedly decreased when the secretion of inflammatory cytokines was increased. Inhibition of miR-206 markedly suppressed inflammatory cytokine secretion and upregulated the expression of TIMP3. In contrast, the upregulation of miR-206 promoted the matrix metalloproteinase (MMP) 9 levels and inhibited TIMP3 levels. Using a dual-luciferase reporter assay, a direct interaction between miR-206 and the 3'-untranslated region (UTR) of TIMP3 was confirmed. SiTIMP3, the small interfering RNA (siRNA) specific for TIMP3, significantly attenuated the suppressive effects of miR-206-inhibitor on inflammatory cytokine secretion and MMP9 expression. Our data suggest that miR-206 may function as an inflammatory regulator and drive the expression of MMP9 in M.tb-infected THP-1 cells by targeting TIMP3, indicating that miR-206 is a potential therapeutic target for patients with TB.


Assuntos
Macrófagos/imunologia , Macrófagos/microbiologia , Metaloproteinase 9 da Matriz/imunologia , MicroRNAs/imunologia , Mycobacterium tuberculosis/imunologia , Inibidor Tecidual de Metaloproteinase-3/imunologia , Linhagem Celular , Citocinas/imunologia , Citocinas/metabolismo , Regulação da Expressão Gênica/imunologia , Humanos , Mediadores da Inflamação/imunologia , Ativação de Macrófagos/imunologia
14.
Radiol Infect Dis ; 1(2): 64-69, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32289065

RESUMO

OBJECTIVE: To investigate the imaging and pathological findings of severe pneumonia caused by human infected avian influenza (H7N9), and therefore to further understand and improve diagnostic accuracy of severe pneumonia caused by human infected avian influenza (H7N9). METHODS: The relevant clinical and imaging data of 19 cases, including 10 males and 9 females, with pneumonia caused by human infected avian influenza (H7N9) was retrospectively analyzed. One of the cases had received percutaneous lung biopsy, with the clinical, imaging and pathological changes possible to be analyzed. RESULTS: The lesions were mainly located at lower lobes and dorsal of lungs, involving multiple lobes and segments. Ground-glass opacities and/or pulmonary opacities were the more often imaging manifestations of severe pneumonia caused by human infected avian influenza (H7N9) in early and evolving phases (19/19,100%). By biopsy following percutaneous lung puncture, exudation of slurry, cellulose, RBC and neutrophils, formation of hyaline membrane, squamous metaplasia and organizing exudates were observable at the alveolar space. Some of alveoli collapsed, and some responded to show compensatory emphysema. CONCLUSION: The imaging features of severe pneumonia caused by human infected avian influenza (H7N9) include obvious ground-glass opacity and pulmonary consolidation, mainly at lower lobes and dorsal of lungs, with rapid changes. The cross-analysis of imaging and pathology preliminary can elucidate the pathological mechanisms of ground-glass opacities and pulmonary consolidation of severe pneumonia. Such an intensive study is beneficial to prompt clinicians to observe and evaluate the progress of the disease. In addition, it is also in favor of managing the symptoms and reducing the mortality rate.

15.
Chempluschem ; 78(10): 1266-1272, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31986785

RESUMO

A new two-phase solution strategy has been developed for the synthesis of multifarious zinc oxide one-dimensional (1D) nanostructures, in which nanorod arrays (NAs), nanorod hollow spheres (NHSs), nanoribbons, nanowires, nanotubes, and nanonetworks were easily obtained at room temperature without using any catalysts, templates, or precursors. More importantly, an interesting formation mechanism of the 1D nanostructures in the benzene/water system and its distinctive size- and morphology-controlling ability were also discovered. Through a series of directed comparison experiments, it was found that the zinc source, reactant concentration, substrate, and reaction time played significant roles in this dipolar binary liquid technique. In addition, and considering their importance to semiconductor ZnO gas-sensing properties, the energy state and surface status of the as-obtained NA and NHS products were investigated through photoluminescence and surface wetting measurements. It was found that a large concentration of oxygen vacancies and high surface energy were present on the surface of the NAs and NHSs, which resulted in their enhanced ethanol gas-sensing properties at a relatively low temperature.

16.
PLoS Pathog ; 8(11): e1002984, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23144609

RESUMO

T-cell immune responses modulated by T-cell immunoglobulin and mucin domain-containing molecule 3 (Tim-3) during Mycobacterium tuberculosis (Mtb) infection in humans remain poorly understood. Here, we found that active TB patients exhibited increases in numbers of Tim-3-expressing CD4(+) and CD8(+) T cells, which preferentially displayed polarized effector memory phenotypes. Consistent with effector phenotypes, Tim-3(+)CD4(+) and Tim-3(+)CD8(+) T-cell subsets showed greater effector functions for producing Th1/Th22 cytokines and CTL effector molecules than Tim-3(-) counterparts, and Tim-3-expressing T cells more apparently limited intracellular Mtb replication in macrophages. The increased effector functions for Tim-3-expressing T cells consisted with cellular activation signaling as Tim-3(+)CD4(+) and Tim-3(+)CD8(+) T-cell subsets expressed much higher levels of phosphorylated signaling molecules p38, stat3, stat5, and Erk1/2 than Tim-3- controls. Mechanistic experiments showed that siRNA silencing of Tim-3 or soluble Tim-3 treatment interfering with membrane Tim-3-ligand interaction reduced de novo production of IFN-γ and TNF-α by Tim-3-expressing T cells. Furthermore, stimulation of Tim-3 signaling pathways by antibody cross-linking of membrane Tim-3 augmented effector function of IFN-γ production by CD4(+) and CD8(+) T cells, suggesting that Tim-3 signaling helped to drive stronger effector functions in active TB patients. This study therefore uncovered a previously unknown mechanism for T-cell immune responses regulated by Tim-3, and findings may have implications for potential immune intervention in TB.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Regulação da Expressão Gênica/imunologia , Memória Imunológica , Proteínas de Membrana/imunologia , Células Th1/imunologia , Tuberculose/imunologia , Feminino , Receptor Celular 2 do Vírus da Hepatite A , Humanos , Interferon gama/imunologia , Ativação Linfocitária/imunologia , Masculino , Transdução de Sinais/imunologia , Fator de Necrose Tumoral alfa/imunologia
17.
Inorg Chem ; 48(23): 11209-14, 2009 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-19856951

RESUMO

The first layered iron borate, Fe(5)O(5)[B(6)O(10)(OH)(3)] x nH(2)O, has been prepared by the boric acid flux method. Its structure, determined by single crystal X-ray diffraction, contains a double FeO(6)-octahedral layer and an unusual [B(6)O(13)] chain. The rigid and cambered [B(6)O(13)] chains bend the octahedral layers, resulting in a wave-like and sandwiched structure. Crystallographic study indicates the structural modulation is mainly from the [B(6)O(13)] chains because of the insertion of water molecules in between. Nevertheless, FeO(6) layers in the average structure, which are well separated by borate chains, is still a reasonable model to understand the two-dimensional magnetism. The strong antiferromagnetic interactions and the complex Fe(3+)-net suggest a possible geometrically magnetic frustration, which may be the reason for the second-order temperature-induced magnetic transition at approximately 125 K. The condensed Fe(3+) layers and the relatively low redox potential at about 1.25 V versus Li(+)/Li show its potentials as an anodic material.

18.
Inorg Chem ; 47(16): 7080-2, 2008 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-18627139

RESUMO

A new aluminum borate chloride (PKU-8) was synthesized in a flux of boric acid, and the structure was established using powder X-ray diffraction techniques. PKU-8 contains an unusual framework structure of a large cage consisting of 12-membered borate rings [B 12O 30] and aluminate octahedra clusters [Al 7O 24].

19.
Dalton Trans ; (13): 1597-601, 2006 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-16547533

RESUMO

A new nickel polyborate, NiB12O14(OH)10 was synthesized using boric acid as a flux. This material has two-dimensional borate layers with a quasi-square lattice of Ni2+. The Ni2+ ions locate in the plane of the two-dimensional layer, bridged through BnO(n+1) chains in the plane and connected with the three-membered ring borate groups out of the plane. The dc and ac magnetic susceptibility, magnetization and specific heat measurements show that this material undergoes a weak ferromagnetic phase transition at Tc = 5.8 K. At T < Tc, a metamagnetic phase transition is observed at about 5 T, associated by a spin-flop, suggesting the ferromagnetic ordering is induced by an antiferromagnetic interaction. A broad maximum in the ac susceptibility at TM = 23-24 K indicates an intermediate short-range ordering.

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