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1.
Front Med (Lausanne) ; 10: 1265544, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38249987

RESUMO

Introduction: Considering the role of bacteria in the onset of acute exacerbation of COPD (AECOPD), we hypothesized that the use of influenza-Streptococcus pneumoniae vaccination, oral probiotics or inhaled amikacin could prevent AECOPD. Methods: In this pilot prospective, muti-central, randomized trial, moderate-to-very severe COPD subjects with a history of moderate-to-severe exacerbations in the previous year were enrolled and assigned in a ratio of 1:1:1:1 into 4 groups. All participants were managed based on the conventional treatment recommended by GOLD 2019 report for 3 months, with three groups receiving additional treatment of inhaled amikacin (0.4 g twice daily, 5-7 days monthly for 3 months), oral probiotic Lactobacillus rhamnosus GG (1 tablet daily for 3 months), or influenza-S. pneumoniae vaccination. The primary endpoint was time to the next onset of moderate-to-severe AECOPD from enrollment. Secondary endpoints included CAT score, mMRC score, adverse events, and survival in 12 months. Results: Among all 112 analyzed subjects (101 males, 96 smokers or ex-smokers, mean ± SD age 67.19 ± 7.39 years, FEV1 41.06 ± 16.09% predicted), those who were given dual vaccination (239.7 vs. 198.2 days, p = 0.044, 95%CI [0.85, 82.13]) and oral probiotics (248.8 vs. 198.2 days, p = 0.017, 95%CI [7.49, 93.59]) had significantly delayed onset of next moderate-to-severe AECOPD than those received conventional treatment only. For subjects with high symptom burden, the exacerbations were significantly delayed in inhaled amikacin group as compared to the conventional treatment group (237.3 vs. 179.1 days, p = 0.009, 95%CI [12.40,104.04]). The three interventions seemed to be safe and well tolerated for patient with stable COPD. Conclusion: The influenza-S. pneumoniae vaccine and long-term oral probiotic LGG can significantly delay the next moderate-to-severe AECOPD. Periodically amikacin inhalation seems to work in symptomatic patients. The findings in the current study warrants validation in future studies with microbiome investigation.Clinical trial registration:https://clinicaltrials.gov/, identifier NCT03449459.

2.
Front Med (Lausanne) ; 8: 640289, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34017841

RESUMO

Background: Patients with chronic obstructive pulmonary disease (COPD) are more susceptible to Aspergillus colonization or infection. Several studies have demonstrated that invasive pulmonary Aspergillosis (IPA) and Aspergillus hypersensitivity (AH) have a detrimental effect on COPD. However, it remains to be clarified whether Aspergillus colonization is associated with acute exacerbation of COPD (AECOPD). This study aimed to explore the impact of Aspergillus colonization in the lower respiratory tract on AECOPD. Method: Patients with Aspergillus colonization were identified from a retrospective cohort of hospitalized AECOPD from 2011 to 2016 in eight centers in Shanghai, China. The demographic information, conditions of the stable stage, clinical characteristics during hospitalization, and 1-year follow-up information after discharge were collected and compared to participants without fungi colonization. Result: Twenty-six hospitalized AECOPD patients with Aspergillus colonization and 72 controls were included in the final analysis after excluding patients with other fungi isolation and matching. The rates of recurrence of acute exacerbation within 90 days and 180 days after discharge in the patients with Aspergillus colonization were both significantly higher than that in the fungi negative patients (90 days: 19.2 vs. 4.2%, p = 0.029; 180 days: 23.1 vs. 4.2%, p = 0.010), and the all-cause mortality within 1 year was also higher (11.5 vs. 0.0%, p = 0.017). Multivariate logistic regression analysis showed that Aspergillus colonization was an independent risk factor for the recurrence of acute exacerbation within 90 days and 180 days (90 days: OR = 8.661, 95% CI: 1.496-50.159, p = 0.016; 180 days: OR =10.723, 95% CI: 1.936-59.394, p = 0.007). Conclusion: Aspergillus colonization may predict poor prognosis of AECOPD while leading to an increased risk of recurrent AECOPD in a short period.

3.
Ann Transl Med ; 8(18): 1179, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33241028

RESUMO

BACKGROUND: The objective of this study was to investigate medication adherence and the associated influencing factors in patients with chronic obstructive pulmonary disease (COPD) who were treated in a primary general hospital in Shanghai China during the 2019 novel coronavirus (COVID-19) pandemic. METHODS: From March to April 2020, all of the COPD patients treated in our department in the last 7 years were interviewed by telephone. The basic patient data and each questionnaire item were collected, and influencing factors were analyzed by the Chi-square test, U test, and univariate and multivariate logistic regression analyses. RESULTS: A total of 191 patients with COPD were queried, and 84 (44.0%) valid questionnaires were obtained. Among them, individuals with group B symptoms were most represented (45.2%); 53.6% had Medical Research Council (MRC) dyspnea levels of 2 or above. Chronic obstructive pulmonary disease assessment test (CAT) had an average of 9 [3, 13], and 52.4% of patients used two-drug combination therapy. Medication adherence was both good in ordinary times and over the past 2 months of the pandemic, and 88.8% of patients had no acute exacerbation during the pandemic. The CAT scores of male patients <70 years old, and patients with general outpatient follow-up and regular gargling were reduced (P<0.05). Drug combination and doctor's supervision were favorable factors affecting medication adherence during the 2 months of the pandemic, while possible depression was an unfavorable factor (P<0.05). CONCLUSIONS: During the pandemic, medication adherence in patients with COPD was similar to that in regular times, and was significantly related to drug combination, doctor's supervision, and accompanying mood disorders. An effective way to improve patient adherence and disease control could be strengthening follow-up education and diagnosing and treating depression and other complications.

4.
J Thorac Dis ; 12(4): 1417-1426, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32395279

RESUMO

BACKGROUND: Despite the release of a national guideline in 2016, the actual practices with respect to adult community-acquired pneumonia (CAP) remain unknown in China. We aimed to investigate CAP patient management practices in Shanghai to identify potential problems and provide evidence for policy making. METHODS: A short-period, 5-day prospective cross-sectional study was performed with sampled pulmonologists from 36 hospitals, encompassing all the administrative districts of Shanghai, during January 8-12, 2018. The medical information was recorded and analyzed for the patients with the diagnosis of CAP who were cared for by 46 pulmonologists during the study period. RESULTS: Overall, 435 patients were included in the final analysis, and 94.3% had a low risk of death in terms of CRB-65 criteria (C: disturbance of consciousness, R: respiratory rate, B: blood pressure, 65: age). When diagnosed with CAP, 70.1% of patients were not evaluated using the CURB-65 score (CRB-65 + U: urea nitrogen), but most patients (95.4%) were evaluated using CRB-65. Time to achieve clinical stability was longer in patients with hypoxemia than in those without hypoxemia (8.42±6.36 vs. 5.53±4.12 days, P=0.004). Overall, 84.4% of patients with a CRB-65 score of 0 were administered antibiotics intravenously, and 19.4% were still hospitalized after excluding hypoxemia and comorbidities. The average duration of antibiotic treatment was 10.4±4.9 days. Overall, 72.6% of patients received antibiotics covering atypical pathogens whose time to clinical stability was significantly shortened compared with those without coverage, but the antibiotic duration was similar and not correspondingly shortened. CONCLUSIONS: CRB-65 seems to be more practical than CURB-65 for the initial evaluation of CAP in the context of local practice, and oxygenation assessment should be included in the evaluation of severity. Overtreatment may be relatively common in patients at low risk of death, including unreasonable hospitalization, intravenous administration, and antibiotic duration.

5.
Artigo em Inglês | MEDLINE | ID: mdl-30587958

RESUMO

OBJECTIVE: The diagnostic value of emphysema extent in consistent air flow limitation remains controversial. Therefore, we aimed to assess the value of emphysema extent on computed tomography (CT) on the diagnosis of persistent airflow limitation. Furthermore, we developed a diagnostic criterion for further verification. MATERIALS AND METHODS: We retrospectively enrolled patients who underwent chest CT and lung function test. To be specific, 671 patients were enrolled in the derivation group (Group 1.1), while 479 patients were in the internal validation group (Group 1.2). The percentage of lung volume occupied by low attenuation areas (LAA%) and the percentile of the histogram of attenuation values were calculated. RESULTS: In patients with persistent airflow limitation, the LAA% was higher and the percentile of the histogram of attenuation values was lower, compared with patients without persistent airflow limitation. Using LAA% with a threshold of -950 HU >1.4% as the criterion, the sensitivity was 44.3% and 47.2%, and the specificity was 95.2% and 95.7%, in Group 1.1 and Group 1.2, respectively. The specificity was influenced by the coexistence of interstitial lung disease, pneumothorax, and post-surgery, rather than the coexistence of pneumonia, nodule, or mass. Multivariable models were also developed. CONCLUSION: The emphysema extent on CT is a highly specific marker in the diagnosis of persistent airflow limitation.


Assuntos
Pulmão/diagnóstico por imagem , Doença Pulmonar Obstrutiva Crônica/diagnóstico por imagem , Enfisema Pulmonar/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Idoso , China , Estudos Transversais , Feminino , Volume Expiratório Forçado , Humanos , Pulmão/fisiopatologia , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Enfisema Pulmonar/fisiopatologia , Reprodutibilidade dos Testes , Estudos Retrospectivos , Índice de Gravidade de Doença , Capacidade Vital
6.
Emerg Microbes Infect ; 7(1): 171, 2018 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-30353004

RESUMO

Seasonal H3N2 influenza viruses are recognized as major epidemic viruses, exhibiting complex seasonal patterns in regions with temperate climates. To investigate the influence of viral evolution and mutations on the seasonality of influenza, we performed a genome-wide analysis of samples collected from 62 influenza A/H3N2-infected patients in Shanghai during 2016-2017. Phylogenetic analysis of all eight segments of the influenza A virus revealed that there were two epidemic influenza virus strains circulating in the 2016-2017 winter season (2016-2017win) and 2017 summer season (2017sum). Replication of the two epidemic viral strains at different temperatures (33, 35, 37, and 39 °C) was measured, and the correlation of the mutations in the two epidemic viral strains with temperature sensitivity and viral replication was analyzed. Analysis of the replication kinetics showed that replication of the 2016-2017win strains was significantly restricted at 39 °C compared with that of the 2017sum strains. A polymerase activity assay and mutational analysis demonstrated that the PA I668V mutation of the 2016-2017win viruses suppressed polymerase activity in vitro at high temperatures. Taken together, these data suggest that the I668V mutation in the PA subunit of the 2016-2017win strains may confer temperature sensitivity and attenuate viral replication and polymerase activity; meanwhile, the 2017sum strains maintained virulence at high temperatures. These findings highlight the importance of certain mutations in viral adaptation and persistence in subsequent seasons.


Assuntos
Vírus da Influenza A Subtipo H3N2/enzimologia , Influenza Humana/virologia , Mutação de Sentido Incorreto , RNA Polimerase Dependente de RNA/genética , Proteínas Virais/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , China/epidemiologia , Feminino , Genoma Viral , Humanos , Vírus da Influenza A Subtipo H3N2/classificação , Vírus da Influenza A Subtipo H3N2/genética , Vírus da Influenza A Subtipo H3N2/isolamento & purificação , Influenza Humana/epidemiologia , Masculino , Pessoa de Meia-Idade , Filogenia , RNA Polimerase Dependente de RNA/metabolismo , Estações do Ano , Temperatura , Proteínas Virais/metabolismo , Adulto Jovem
7.
Clin Respir J ; 12(4): 1320-1360, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28756639

RESUMO

Community-acquired pneumonia (CAP) in adults is an infectious disease with high morbidity in China and the rest of the world. With the changing pattern in the etiological profile of CAP and advances in medical techniques in diagnosis and treatment over time, Chinese Thoracic Society of Chinese Medical Association updated its CAP guideline in 2016 to address the standard management of CAP in Chinese adults. Extensive and comprehensive literature search was made to collect the data and evidence for experts to review and evaluate the level of evidence. Corresponding recommendations are provided appropriately based on the level of evidence. This updated guideline covers comprehensive topics on CAP, including aetiology, antimicrobial resistance profile, diagnosis, empirical and targeted treatments, adjunctive and supportive therapies, as well as prophylaxis. The recommendations may help clinicians manage CAP patients more effectively and efficiently. CAP in pediatric patients and immunocompromised adults is beyond the scope of this guideline. This guideline is only applicable for the immunocompetent CAP patients aged 18 years and older. The recommendations on selection of antimicrobial agents and the dosing regimens are not mandatory. The clinicians are recommended to prescribe and adjust antimicrobial therapies primarily based on their local etiological profile and results of susceptibility testing, with reference to this guideline.


Assuntos
Antibacterianos/administração & dosagem , Infecções Comunitárias Adquiridas/tratamento farmacológico , Pneumonia/tratamento farmacológico , Guias de Prática Clínica como Assunto , Sociedades Médicas , Cirurgia Torácica , Adulto , Fatores Etários , China/epidemiologia , Infecções Comunitárias Adquiridas/epidemiologia , Sistemas de Liberação de Medicamentos , Humanos , Incidência , Pneumonia/epidemiologia , Prognóstico , Estudos Retrospectivos
8.
Artigo em Inglês | MEDLINE | ID: mdl-29250493

RESUMO

Tuberculosis (TB) remains one of the most severe infectious diseases. It is still of paramount importance to establish more accurate, rapid, and efficient diagnostic methods. Since infection with Mycobacterium tuberculosis (M. tb) is largely mediated through the respiratory tract, IgA responses against mycobacterial proteins are worthy of investigation for their potential clinical utility. In this study, the IgA response targeting lipoprotein Z (LppZ) was determined by using a homemade ELISA with plasma of TB patients (N = 125), LTBI individuals (N = 92), healthy controls (HCs) (N = 165), as well as TB patients undergoing anti-TB treatment (N = 9). In parallel the antigen-specific IFN-γ release from PBMCs triggered by LppZ and M. tb-specific ESAT-6 or CFP-10 was detected by using an ELISPOT assay. It was found that the LppZ-specific IgA level was dramatically higher in TB patients than in HCs (p < 0.0001). Compared to that before anti-TB treatment, the LppZ-specific IgA level decreased substantially after 2 months of anti-TB treatment (p = 0.0297) and remained at low levels until the end of the treatment. What is more, pulmonary TB patients exhibited significantly higher LppZ-specific IgA-values than extra-pulmonary TB patients (p = 0.0296). Interestingly, the LppZ-specific IgA-values were negatively correlated to the amounts of IFN-γ released in response to LppZ with statistical significance (r = -0.5806, p = 0.0002). LppZ-specific IgA level was also higher in LTBI individuals than in HCs (p < 0.0001). Additionally there were some PPD+ HC individuals with high LppZ-specific IgA levels but the potential of this assay for identifying leaky LTBI in PPD+ HCs needs to be further investigated through follow-up studies. The sensitivity of detecting TB solely with ESAT-6 or CFP-10-specific IFN-γ release was increased by including the LppZ-specific IgA results, respectively, from 86.11 to 100% and 88.89 to 100%; the sensitivity of screening for LTBI was increased from 80.36 to 83.93% and 57.14 to 69.64%, respectively. The higher LppZ-specific IgA responses in TB and LTBI populations than in controls indicated high immunoreactivity to LppZ upon M. tb infection. Although the assay was not efficient enough for independent application in sero-diagnosis, LppZ-specific IgA might become a complementary biomarker for the improvement of TB and LTBI screening.


Assuntos
Imunoglobulina A/isolamento & purificação , Tuberculose Latente/diagnóstico , Tuberculose Latente/imunologia , Lipoproteínas/isolamento & purificação , Mycobacterium tuberculosis/imunologia , Tuberculose/diagnóstico , Tuberculose/imunologia , Adulto , Idoso , Antígenos de Bactérias/imunologia , Proteínas de Bactérias/imunologia , Biomarcadores , ELISPOT/métodos , Feminino , Humanos , Imunidade Celular , Interferon gama/metabolismo , Tuberculose Latente/microbiologia , Leucócitos Mononucleares/imunologia , Leucócitos Mononucleares/microbiologia , Lipoproteínas/genética , Masculino , Pessoa de Meia-Idade , Mycobacterium tuberculosis/isolamento & purificação , Sensibilidade e Especificidade , Tuberculose Pulmonar/diagnóstico , Tuberculose Pulmonar/imunologia , Tuberculose Pulmonar/microbiologia
9.
BMC Pulm Med ; 16: 8, 2016 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-26758377

RESUMO

BACKGROUND: As-needed formoterol can effectively relieve asthma symptoms. Since budesonide/formoterol is available as maintenance and reliever therapy in Asia, formoterol is now being used as-needed, but always with concomitant inhaled corticosteroids. The objective of this analysis was to assess the safety and efficacy of formoterol therapy in patients in East Asia (China, Indonesia, Korea, the Philippines and Singapore) with asthma. METHODS: Post-hoc analyses of data from the East Asian population of the RELIEF (REal LIfe EFfectiveness of Oxis® Turbuhaler® as-needed in asthmatic patients; study identification code: SD-037-0699) study were performed. RESULTS: This sub-group comprised 2834 randomised patients (formoterol n = 1418; salbutamol n = 1416) with mean age 35 years; 50.7% were male. 2678 patients completed the study. There was no significant difference in the total number of adverse events (AEs) reported in the formoterol and salbutamol groups (21.3% vs 20.9% of patients; p = 0.813), nor in the total number of serious AEs and/or discontinuations due to AEs (4.6% vs 5.5%, respectively; p = 0.323). Compared with salbutamol, formoterol was associated with a significantly longer time to first exacerbation (hazard ratio 0.86; p = 0.023) and a 14% reduction in the risk of any exacerbation (p < 0.05). Relative to salbutamol, mean adjusted reliever medication use throughout the study was significantly lower in the formoterol group (p = 0.017) and the risk of increased asthma medication use was 20% lower with formoterol (p = 0.005). CONCLUSIONS: Among patients with asthma in East Asia, as-needed formoterol and salbutamol had similar safety profiles but, compared with salbutamol, formoterol reduced the risk of exacerbations, increased the time to first exacerbation and reduced the need for reliever medication.


Assuntos
Agonistas de Receptores Adrenérgicos beta 2/uso terapêutico , Albuterol/uso terapêutico , Asma/tratamento farmacológico , Fumarato de Formoterol/uso terapêutico , Administração por Inalação , Adolescente , Adulto , Idoso , Criança , China , Feminino , Humanos , Indonésia , Masculino , Pessoa de Meia-Idade , Filipinas , Modelos de Riscos Proporcionais , República da Coreia , Singapura , Resultado do Tratamento , Adulto Jovem
10.
Chin Med J (Engl) ; 126(23): 4403-8, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24286397

RESUMO

BACKGROUND: Interleukin-13 (IL-13) has been implicated to be responsible for recruitment of inflammatory cells from the blood to the lung, regulation of matrix metalloproteinase and induction of mucin production and secretion in chronic obstructive pulmonary disease (COPD). We determined plasma IL-13 levels in patients with COPD and investigated its association with common polymorphisms of IL-13 gene in a case-control study. METHODS: We genotyped 160 cases and 175 control subjects in a local hospital using Mass-Array(TM) Technology Platform then tested the association of four SNPs in IL-13 (rs1295685, rs1800925, rs1881457, rs20541) with COPD, and then determined plasma IL-13 levels in patients with COPD and controls. RESULTS: Association was found between IL-13 gene SNPs (rs20541 and rs1800925) and an increased risk of COPD. By linkage disequilibrium (LD) analysis, two blocks (rs1881457 and rs1800925; rs20541 and rs1295685) were found. The risk of COPD was found associated with the IL-13 gene polymorphism among southern Chinese Han population. Plasma IL-13 level was increased in COPD patients compared with controls. CONCLUSIONS: The polymorphism of the IL-13 gene is associated with an increased risk of COPD in southern Chinese Han population. Plasma IL-13 levels were found elevated in patients with COPD.


Assuntos
Interleucina-13/genética , Doença Pulmonar Obstrutiva Crônica/genética , Adulto , Idoso , Povo Asiático/genética , Estudos de Casos e Controles , Frequência do Gene/genética , Predisposição Genética para Doença/genética , Genótipo , Haplótipos/genética , Humanos , Desequilíbrio de Ligação/genética , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único/genética
12.
PLoS Pathog ; 5(7): e1000534, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19649276

RESUMO

The well-recognized phospholipids (PLs) of Mycobacterium tuberculosis (Mtb) include several acidic species such as phosphatidylglycerol (PG), cardiolipin, phosphatidylinositol and its mannoside derivatives, in addition to a single basic species, phosphatidylethanolamine. Here we demonstrate that an additional basic PL, lysinylated PG (L-PG), is a component of the PLs of Mtb H37Rv and that the lysX gene encoding the two-domain lysyl-transferase (mprF)-lysyl-tRNA synthetase (lysU) protein is responsible for L-PG production. The Mtb lysX mutant is sensitive to cationic antibiotics and peptides, shows increased association with lysosome-associated membrane protein-positive vesicles, and it exhibits altered membrane potential compared to wild type. A lysX complementing strain expressing the intact lysX gene, but not one expressing mprF alone, restored the production of L-PG and rescued the lysX mutant phenotypes, indicating that the expression of both proteins is required for LysX function. The lysX mutant also showed defective growth in mouse and guinea pig lungs and showed reduced pathology relative to wild type, indicating that LysX activity is required for full virulence. Together, our results suggest that LysX-mediated production of L-PG is necessary for the maintenance of optimal membrane integrity and for survival of the pathogen upon infection.


Assuntos
Peptídeos Catiônicos Antimicrobianos/farmacologia , Lisina/metabolismo , Lisofosfolipídeos/biossíntese , Mycobacterium tuberculosis/metabolismo , Fosfatidilgliceróis/biossíntese , Animais , Proteínas de Bactérias/biossíntese , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Citocinas/metabolismo , Farmacorresistência Bacteriana , Feminino , Cobaias , Humanos , Pulmão/metabolismo , Pulmão/patologia , Lisina/genética , Proteínas de Membrana Lisossomal/metabolismo , Macrófagos/metabolismo , Potenciais da Membrana , Camundongos , Camundongos Endogâmicos C57BL , Mutação , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/genética , Fagossomos/metabolismo , Fenótipo , Fosfatidilgliceróis/química , Fosfatidilgliceróis/metabolismo , Fosfolipídeos/metabolismo , Estrutura Terciária de Proteína , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
13.
Infect Immun ; 77(2): 598-603, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19064634

RESUMO

The rabbit model of tuberculosis is attractive because of its pathophysiologic resemblance to the disease in humans. Rabbits are naturally resistant to infection but may manifest cavitary lung lesions. We describe here a novel approach that utilizes presensitization and bronchoscopic inoculation to reliably produce cavities in the rabbit model. With a fixed inoculum of bacilli, we were able to reproducibly generate cavities by using Mycobacterium bovis Ravenel, M. bovis AF2122, M. bovis BCG, M. tuberculosis H37Rv, M. tuberculosis CDC1551, and the M. tuberculosis CDC1551 DeltasigC mutant. M. bovis infections generated cavitary CFU counts of 10(6) to 10(9) bacilli, while non-M. bovis species and BCG yielded CFU counts that ranged from 10(4) to 10(8) bacilli. Extrapulmonary dissemination was almost exclusively noted among rabbits infected with M. bovis Ravenel and AF2122. Though all of the species yielded secondary lesions at intrapulmonary sites, M. bovis infections led to the most apparent gross pathology. Using the M. tuberculosis icl and dosR gene expression patterns as molecular sentinels, we demonstrated that both the cavity wall and cavity lumen are microenvironments associated with hypoxia, upregulation of the bacterial dormancy program, and the use of host lipids for bacterial catabolism. This unique cavitary model provides a reliable animal model to study cavity pathogenesis and extrapulmonary dissemination.


Assuntos
Mycobacterium bovis/fisiologia , Mycobacterium tuberculosis/fisiologia , Tuberculose Pulmonar/microbiologia , Tuberculose Pulmonar/patologia , Animais , Broncoscopia , Modelos Animais de Doenças , Regulação Bacteriana da Expressão Gênica/fisiologia , Pulmão/patologia , Mycobacterium tuberculosis/genética , Coelhos , Reprodutibilidade dos Testes
14.
J Infect Dis ; 198(10): 1520-8, 2008 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-18956986

RESUMO

BACKGROUND: Tuberculosis of the central nervous system (CNS) is a serious, often fatal disease primarily affecting young children. It develops after hematogenous dissemination and subsequent invasion of the CNS by Mycobacterium tuberculosis. The microbial determinants involved in CNS disease are poorly characterized. METHODS: Hematogenously disseminated M. tuberculosis infection was simulated in BALB/c mice by intravenous challenge. Bacteria were recovered using standard culture techniques. Host immune response to M. tuberculosis infection was assessed by histopathological and cytokine profile analysis. By means of a pooled infection with genotypically defined M. tuberculosis mutants, bacterial genes required for invasion or survival were determined in the CNS and lung tissue. RESULTS: M. tuberculosis were detected in whole mouse brains as early as 1 day after intravenous infection and at all time points assessed thereafter. No significant immune response was elicited in the infected brain tissue, compared with extensive inflammation in the infected lung tissue at the same time point. We identified mutants for 5 M. tuberculosis genes (Rv0311, Rv0805, Rv0931c, Rv0986, and MT3280) with CNS-specific phenotypes, absent in lung tissue. CONCLUSIONS: We have identified CNS-specific M. tuberculosis genes involved in the pathogenesis of tuberculosis. Further characterization of these genes will help in understanding the microbial pathogenesis of CNS tuberculosis.


Assuntos
Sistema Nervoso Central/microbiologia , Mycobacterium tuberculosis/fisiologia , Tuberculose do Sistema Nervoso Central/microbiologia , Animais , Sistema Nervoso Central/imunologia , Citocinas/imunologia , Modelos Animais de Doenças , Feminino , Genes Bacterianos/genética , Camundongos , Camundongos Endogâmicos BALB C , Mutação/genética , Mycobacterium tuberculosis/genética , Tuberculose do Sistema Nervoso Central/imunologia
15.
Arthritis Rheum ; 58(4): 1146-55, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18383370

RESUMO

OBJECTIVE: Beta2-glycoprotein I (beta2GPI) is an important autoantigen in the antiphospholipid syndrome (APS). In vitro studies suggest that it may have multifaceted physiologic functions, since it displays both anticoagulant and procoagulant properties. We have previously reported that beta2GPI can directly bind thrombin, a key serine protease in the coagulation pathway. The present study was undertaken to examine the influence of beta2GPI on thrombin inactivation by the serpin heparin cofactor II (HCII). The effect of anti-beta2GPI antibodies was also examined. METHODS: HCII inactivation of thrombin was assessed using chromogenic and various platelet functional assays. The influence of intact and proteolytically cleaved beta2GPI and anti-beta2GPI antibodies was determined in these systems. RESULTS: beta2GPI protected thrombin against inactivation by HCII/heparin. Cleavage of beta2GPI at Lys317-Thr318 abrogated its protective effect. Patient polyclonal IgG and murine monoclonal anti-beta2GPI antibodies potentiated the procoagulant influence of beta2GPI in this system. CONCLUSION: These novel findings suggest that beta2GPI may regulate thrombin inactivation by HCII/heparin. The observation that anti-beta2GPI antibodies potentiate the protective effect of beta2GPI on thrombin in this system, thereby promoting a procoagulant response, may potentially delineate one of the pathophysiologic mechanisms contributing to the prothrombotic tendency in patients with APS.


Assuntos
Autoanticorpos/fisiologia , Coagulação Sanguínea/fisiologia , Cofator II da Heparina/fisiologia , Trombina/fisiologia , beta 2-Glicoproteína I/sangue , Adulto , Anticoagulantes , Autoanticorpos/sangue , Coagulação Sanguínea/imunologia , Feminino , Heparina/farmacologia , Humanos , Masculino , beta 2-Glicoproteína I/imunologia
16.
J Infect Dis ; 195(11): 1634-42, 2007 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-17471433

RESUMO

BACKGROUND: Mouse and guinea pig models have been used to identify Mycobacterium tuberculosis mutants attenuated for survival. However, unlike mice, M. tuberculosis-infected guinea pigs form caseating granulomas, which may simulate human disease more closely. METHODS: We used designer arrays for defined mutant analysis, a high-throughput subtractive competition assay, for genotypically defined M. tuberculosis mutants and compared the survival of the same mutant pools in guinea pig and mouse aerosol models. Selected mutants found to be attenuated in either aerosol model were also analyzed in the mouse hollow-fiber model. RESULTS: M. tuberculosis mutants representing 74 genes were tested. Eighteen M. tuberculosis mutants were attenuated for survival in either aerosol model, with 70% of selected mutants also attenuated in the mouse hollow-fiber model. The majority of attenuated mutants in the mouse aerosol model were detected only after 90 days of infection. There was a high degree of concordance between the genes identified by the 2 aerosol models, with detection being significantly earlier in the guinea pig (P<.0003). CONCLUSIONS: We identified M. tuberculosis genes required for survival in mammalian lungs. The majority of mouse late-stage survival mutants were detected significantly earlier in the guinea pig, which suggests that differences in tuberculosis-induced lung pathologic changes may account for this accelerated detection.


Assuntos
Proteínas de Bactérias/genética , Pulmão/microbiologia , Mycobacterium tuberculosis/crescimento & desenvolvimento , Mycobacterium tuberculosis/patogenicidade , Tuberculose Pulmonar/microbiologia , Animais , Proteínas de Bactérias/metabolismo , Elementos de DNA Transponíveis , Modelos Animais de Doenças , Feminino , Cobaias , Humanos , Pulmão/patologia , Camundongos , Camundongos Endogâmicos BALB C , Mutagênese Insercional , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , Especificidade da Espécie , Tuberculose Pulmonar/patologia
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