601 research outputs found

    Proteomic and Physiological Analyses Reveal Putrescine Responses in Roots of Cucumber Stressed by NaCl

    Get PDF
    Soil salinity is a major environmental constraint that threatens agricultural productivity. Different strategies have been developed to improve crop salt tolerance, among which the effects of polyamines have been well-reported. To gain a better understanding of the cucumber (Cucumis sativus L.) responses to NaCl and unravel the underlying mechanism of exogenous putrescine (Put) alleviating salt-induced damage, comparative proteomic analysis was conducted on cucumber roots treated with NaCl, and/or Put for 7 days. The results showed that exogenous Put restored the root growth inhibited by NaCl. Sixty-two differentially expressed proteins implicated in various biological processes were successfully identified by MALDI-TOF/TOF MS. The four largest categories included proteins involved in defense response (24.2%), protein metabolism (24.2%), carbohydrate metabolism (19.4%), and amino acid metabolism (14.5%). Exogenous Put up-regulated most identified proteins involved in carbohydrate metabolism, implying an enhancement in energy generation. Proteins involved in defense response and protein metabolism were differently regulated by Put, which indicated the roles of Put in stress resistance and proteome rearrangement. Put also increased the abundance of proteins involved in amino acid metabolism. Meanwhile, physiological analysis showed that Put could further up-regulated the levels of free amino acids in salt stressed-roots. In addition, Put also improved endogenous polyamines contents by regulating the transcription levels of key enzymes in polyamine metabolism. Taken together, these results suggest that Put may alleviate NaCl-induced growth inhibition through degradation of misfolded/damaged proteins, activation of stress defense, and the promotion of carbohydrate metabolism to generate more energy

    Anatomic evidence shows that lymphatic drainage exists in the pituitary to loop the cerebral lymphatic circulation

    Get PDF
    Respiratory infections can result in intracranial infections and unknown neurological symptoms. The central nervous system lacks classical meningeal lymphatic (circulation) drainage, and the exact underlying mechanisms of how immune cells from the peripheral lymphatic system enter the central nervous system (CNS) remain unknown. To determine whether the perinasal lymphatic system or lymphatic vessels are involved in cerebral immune defence and play a role in causing CNS infections (especially respiratory tract-related infections), we performed an anatomic study to investigate the drainage differences between the perinasal and intracerebral lymphatic systems by using injection of Evans blue and anatomic surgery, together with immunohistochemistry and immunofluorescence assays. Surprisingly, we found that (1) the pituitary (adenohypophysis) is involved and is rich in lymphatic vessels and (2) perinasal tissue could communicate with central pituitary lymphatic vessels in a specific and unidirectional manner. Taken together, our study may be the first to anatomically demonstrate the existence of novel lymphatic vessel structures in the pituitary, as well as their communication with the perinasal (lymphatic) tissue. Our findings suggest the existence of an ultimate loop for “classical” meningeal lymphatic drainage and are relevant to cerebral infection and immune defence

    Gene silencing of β-galactosamide α-2,6-sialyltransferase 1 inhibits human influenza virus infection of airway epithelial cells

    Full text link
    BACKGROUND: Human influenza virus hemagglutinin prefers to use sialic acid (SA) receptors via α-2,6 linkages. The β-galactoside α-2,6-sialyltransferase I (ST6Gal I) protein is encoded by the ST6GAL1 gene and is responsible for the addition of α-2,6 linked SA to the Galβ1-4GlcNAc disaccharide of glycans and glycoproteins found on the cellular surface. Therefore, ST6GAL1 could be a potential target for anti-influenza therapeutics. We used specific small interfering RNAs (siRNAs) to block expression of ST6GAL1 and limit distribution of SA receptors on the surface of airway epithelial cells. RESULTS: The siRNA duplexes we used inhibited ST6GAL1 mRNA expression and subsequent expression of the encoding protein. As a result, synthesis of α-2,6 SA galactose was inhibited. Adsorption of influenza virus particles to the surface of cells transfected with appropriate specific siRNAs was significantly reduced. Intracellular viral genome copy number and virus titer within the supernatant of cells transfected with siRNAs was significantly reduced in a dose-dependent manner compared with those for untransfected cells and cells transfected with non-specific siRNAs. CONCLUSIONS: We used siRNAs targeting ST6GAL1 to inhibit the expression of certain cell surface receptors, thereby preventing virus adsorption. This resulted in the inhibition of human influenza virus infection. Our findings are a significant development in the identification of potential new anti-influenza drug targets

    An assessment of the quality of randomised controlled trials conducted in China

    Get PDF
    Background: Despite the rapid increase in research in China, little is known about the quality of clinical trials conducted there.Methods: A systematic review and critical appraisal of randomised controlled trials (RCTs) conducted in China and published in 2004 was undertaken to describe their characteristics, assess the quality of their reporting, and where possible, the quality of their conduct. Randomised controlled trials in all disease areas and types of interventions, which took place in China and included Chinese citizens were identified using PubMed and hand searching the Journal Series of the Chinese Medical Association. Quality was assessed against a subset of criteria adapted from the CONSORT statement.Results: Three hundred and seven RCTs were included. One hundred and ninety-nine (64.8%) failed to report methods of randomization and 254 (82.4%) did not mention blinding of either participants or investigators. Reporting of baseline characteristics, primary outcome and length of follow-up was inadequate in a substantial proportion of studies. Fewer than 11% of RCTs mentioned ethical approval and only 18.0% adequately discussed informed consent. However, dropout rates were very favourable with nearly 44% of trials reporting a zero dropout rate.Conclusion: Reporting of RCTs in China requires substantial improvement to meet the targets of the CONSORT statement. The conduct of Chinese RCTs cannot be directly inferred from the standard of reporting; however without good reporting the methods of the trials cannot be clearly ascertained

    Real-life effectiveness of budesonide/formoterol maintenance and reliever therapy in asthma patients across Asia: SMARTASIA study

    Get PDF
    BACKGROUND: The use of budesonide/formoterol in a single inhaler for both maintenance and reliever therapy is a recommended option for treatment of persistent asthma not responding well to inhaled corticosteroid (ICS) alone. METHODS: This was a multi-centre open-label study on patients whose asthma condition remained inadequately controlled by various asthma treatments other than budesonide/formoterol. After a 2-week run-in period, eligible patients underwent a 12-week treatment period with budesonide/formoterol (Symbicort SMART®, 160/4.5 μg) twice daily plus as needed. Patient’s asthma control and quality of life were assessed using the 5-item Asthma Control Questionnaire (ACQ-5) and the standardized Asthma Quality of Life Questionnaire (AQLQ-S), respectively. RESULTS: A total of 862 eligible asthma patients who have had asthma for a mean duration of 10.73 ± 12.03 years entered a 12-week treatment with budesonide/formoterol maintenance and reliever therapy. During treatment, ACQ-5 score improved significantly by 0.58 ± 0.93 (95% CI, 0.51 to 0.64, P < 0.0001) from the baseline level of 1.62 ± 1.00. AQLQ(S) score improved by 0.70 ± 0.89 (95% CI, 0.64 to 0.76, P < 0.0001) from baseline. Asthma symptom score was also reduced significantly (P < 0.0001); between run-in and treatment periods, night- and day-time symptom scores were reduced by 0.32 ± 0.54 (95% CI, 0.28 to 0.35) and 0.30 ± 0.52 (95% CI, 0.27 to 0.34), respectively. The percentage of nights with awakenings due to asthma symptoms was reduced by 11.09 ± 26.13% (95% CI, 9.34 to 12.85%), while the percentage of asthma-control and symptom-free days increased by 20.90 ± 34.40% (95% CI, 18.59 to 23.21%) and 23.89 ± 34.62% (95% CI, 21.56 to 26.21%), respectively (P < 0.0001). Together with the improvement in asthma control, the number of night- and day-time inhalations of as-needed reliever medication decreased by 0.30 ± 0.82 (95% CI, 0.24 to 0.35) inhalations and 0.30 ± 0.97 (95% CI, 0.23 to 0.36) inhalations, respectively (P < 0.0001). No unexpected adverse events were reported. CONCLUSION: During treatment of inadequately controlled asthmatic patients with budesonide/formoterol maintenance and reliever therapy, significant improvement in patients’ asthma control and reductions in asthma symptoms and as-needed medication use was observed. Patients’ quality of life was improved and the treatment was well tolerated. TRIAL REGISTRATION: ClinicalTrial.gov: (NCT00939341

    Bacteria in sputum of stable severe asthma and increased airway wall thickness

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Patients with chronic asthma have thicker intrapulmonary airways measured on high resolution computed tomography (HRCT). We determined whether the presence of lower airway bacteria was associated with increased airway wall thickness.</p> <p>Methods</p> <p>In 56 patients with stable severe asthma, sputum specimens obtained either spontaneously or after induction with hypertonic saline were cultured for bacteria and thoracic HRCT scans obtained. Wall thickness (W<sub>T</sub>) and area (W<sub>A</sub>) expressed as a ratio of airway diameter (D) and total area, respectively, were measured at five levels.</p> <p>Results</p> <p>Positive bacterial cultures were obtained in 29 patients, with <it>H. influenzae, P. aeruginosa </it>and <it>S. aureus </it>being the commonest strains. Logistic regression analysis showed that this was associated with the duration of asthma and the exacerbations during the past year. In airways > 2 mm, there was no significant difference in W<sub>A </sub>(67.5 ± 5.4 vs 66.4 ± 5.4) and W<sub>T</sub>/D (21.6 ± 2.7 vs 21.3 ± 2.4) between the culture negative versus positive groups. Similarly, in airways (≤ 2 mm), there were no significant differences in these parameters. The ratio of √wall area to P<sub>i </sub>was negatively correlated with FEV<sub>1</sub>% predicted (p < 0.05).</p> <p>Conclusions</p> <p>Bacterial colonization of the lower airways is common in patients with chronic severe asthma and is linked to the duration of asthma and having had exacerbations in the past year, but not with an increase in airway wall thickness.</p

    Vitamin C Mitigates Oxidative Stress and Tumor Necrosis Factor-Alpha in Severe Community-Acquired Pneumonia and LPS-Induced Macrophages

    Full text link
    Oxidative stress is an important part of host innate immune response to foreign pathogens. However, the impact of vitamin C on oxidative stress and inflammation remains unclear in community-acquired pneumonia (CAP). We aimed to determine the effect of vitamin C on oxidative stress and inflammation. CAP patients were enrolled. Reactive oxygen species (ROS), DNA damage, superoxide dismutases (SOD) activity, tumor necrosis factor-alpha (TNF-α), and IL-6 were analyzed in CAP patients and LPS-stimulated macrophages cells. MH-S cells were transfected with RFP-LC3 plasmids. Autophagy was measured in LPS-stimulated macrophages cells. Severe CAP patients showed significantly increased ROS, DNA damage, TNF-α, and IL-6. SOD was significantly decreased in severe CAP. Vitamin C significantly decreased ROS, DNA damage, TNF-α, and IL-6. Vitamin C inhibited LPS-induced ROS, DNA damage, TNF-α, IL-6, and p38 in macrophages cells. Vitamin C inhibited autophagy in LPS-induced macrophages cells. These findings indicated that severe CAP exhibited significantly increased oxidative stress, DNA damage, and proinflammatory mediator. Vitamin C mitigated oxidative stress and proinflammatory mediator suggesting a possible mechanism for vitamin C in severe CAP

    Role of BAFF in pulmonary autoantibody responses induced by chronic cigarette smoke exposure in mice

    Get PDF
    Emerging evidence suggests that autoimmune processes are implicated in the pathogenesis of chronic obstructive pulmonary disease (COPD). In this study, we assessed the expression of B-cell activating factor (BAFF) in smokers, and investigated the functional importance of BAFF in the induction and maintenance of cigarette smoke-induced pulmonary antinuclear antibodies (ANA) and tertiary lymphoid tissues (TLTs) using a preclinical mouse model. We observed that BAFF levels were elevated in smokers and mice exposed to cigarette smoke. In mice, BAFF expression was rapidly induced in the lungs following 4 days of cigarette smoke exposure and remained elevated following 8 and 24 weeks of exposure. Alveolar macrophages were the major source of BAFF Blockade of BAFF using a BAFF receptor-Fc (BAFFR-Fc) construct prevented pulmonary ANA and TLT formation when delivered concurrent with cigarette smoke exposure. Under these conditions, no impact on lung inflammation was observed. However, administration of BAFFR-Fc following smoking cessation markedly reduced the number of TLTs and ANA levels and, of note, reduced pulmonary neutrophilia. Altogether, this study shows for the first time a central role of BAFF in the induction and maintenance of cigarette smoke-induced pulmonary ANA and suggests that BAFF blockade following smoking cessation could have beneficial effects on persistent inflammatory processes.In this study, we assessed the expression of B-cell activating factor (BAFF) in smokers, and investigated the functional importance of BAFF in the induction and maintenance of cigarette smoke-induced pulmonary antinuclear antibodies (ANA) and tertiary lymphoid tissues (TLTs) using a preclinical mouse model. Data presented show that BAFF plays a central role in the induction and maintenance of cigarette smoke-induced pulmonary ANA and suggest a therapeutic potential for BAFF blockade in limiting autoimmune processes associated with smoking
    corecore