Reduction in Rubicon by cigarette smoke is associated with impaired phagocytosis and occurs through lysosomal degradation pathway.

BACKGROUND: A common feature of COPD is a defective lung macrophage phagocytic capacity that can contribute to chronic lung inflammation and infection. The precise mechanisms remain incompletely understood, although cigarette smoke is a known contributor. We previously showed deficiency of the LC3-associated phagocytosis (LAP) regulator, Rubicon, in macrophages from COPD subjects and in response to cigarette smoke. The current study investigated the molecular basis by which cigarette smoke extract (CSE) reduces Rubicon in THP-1, alveolar and blood monocyte-derived macrophages, and the relationship between Rubicon deficiency and CSE-impaired phagocytosis. METHODOLOGY: Phagocytic capacity of CSE-treated macrophages was measured by flow cytometry, Rubicon expression by Western blot and real time polymerase chain reaction, and autophagic-flux by LC3 and p62 levels. The effect of CSE on Rubicon degradation was determined using cycloheximide inhibition and Rubicon protein synthesis and half-life assessment. RESULTS: Phagocytosis was significantly impaired in CSE-exposed macrophages and strongly correlated with Rubicon expression. CSE-impaired autophagy, accelerated Rubicon degradation, and reduced its half-life. Lysosomal protease inhibitors, but not proteasome inhibitors, attenuated this effect. Autophagy induction did not significantly affect Rubicon expression. CONCLUSIONS: CSE decreases Rubicon through the lysosomal degradation pathway. Rubicon degradation and/or LAP impairment may contribute to dysregulated phagocytosis perpetuated by CSE.

Immunolocalization of zinc transporters and metallothioneins reveals links to microvascular morphology and functions.

Zinc homeostasis is vital to immune and other organ system functions, yet over a quarter of the world's population is zinc deficient. Abnormal zinc transport or storage protein expression has been linked to diseases, such as cancer and chronic obstructive pulmonary disorder. Although recent studies indicate a role for zinc regulation in vascular functions and diseases, detailed knowledge of the mechanisms involved remains unknown. This study aimed to assess protein expression and localization of zinc transporters of the SLC39A/ZIP family (ZIPs) and metallothioneins (MTs) in human subcutaneous microvessels and to relate them to morphological features and expression of function-related molecules in the microvasculature. Microvessels in paraffin biopsies of subcutaneous adipose tissues from 14 patients undergoing hernia reconstruction surgery were analysed for 9 ZIPs and 3 MT proteins by MQCM (multifluorescence quantitative confocal microscopy). Zinc regulation proteins detected in human microvasculature included ZIP1, ZIP2, ZIP8, ZIP10, ZIP12, ZIP14 and MT1-3, which showed differential localization among endothelial and smooth muscle cells. ZIP1, ZIP2, ZIP12 and MT3 showed significantly (p < 0.05) increased immunoreactivities, in association with increased microvascular muscularization, and upregulated ET-1, α-SMA and the active form of p38 MAPK (Thr180/Tyr182 phosphorylated, p38 MAPK-P). These findings support roles of the zinc regulation system in microvascular physiology and diseases.

COPD is associated with increased pro-inflammatory CD28null CD8 T and NKT-like cells in the small airways.

We previously showed increased steroid-resistant CD28null CD8+ senescent lymphocyte subsets in the peripheral blood from patients with chronic obstructive pulmonary disease (COPD). These cells expressed decreased levels of the glucocorticoid receptor (GCR), suggesting their contribution to the steroid-resistant property of these cells. COPD is a disease of the small airways (SA). We, therefore, hypothesized that there would be a further increase in these steroid-resistant lymphocytes in the lung, particularly in the SA. We further hypothesized that the pro-inflammatory/cytotoxic potential of these cells could be negated using prednisolone with low-dose cyclosporin A. Blood, bronchoalveolar lavage, large proximal, and small distal airway brushings were collected from 11 patients with COPD and 10 healthy aged-matched controls. The cytotoxic mediator granzyme b, pro-inflammatory cytokines IFNγ/TNFα, and GCR were determined in lymphocytes subsets before and after their exposure to 1µM prednisolone and/or 2.5 ng/mL cyclosporin A. Particularly in the SA, COPD subjects showed an increased percentage of CD28null CD8 T-cells and NKT-like cells, with increased expression of granzyme b, IFNγ and TNFα and a loss of GCR, compared with controls. Significant negative correlations between SA GCR expression and IFNγ/TNFα production by T and NKT-like cells (eg, T-cell IFNγ R = -0.834, P = 0.031) and with FEV1 (R = -0.890) were shown. Cyclosporine A and prednisolone synergistically increased GCR expression and inhibited pro-inflammatory cytokine production by CD28null CD8- T and NKT-like cells. COPD is associated with increased pro-inflammatory CD28null CD8+ T and NKT-like cells in the SA. Treatments that increase GCR in these lymphocyte subsets may improve the efficacy of clinical treatment.

Inhibition of LC3-associated phagocytosis in COPD and in response to cigarette smoke.

INTRODUCTION/RATIONALE: In chronic obstructive pulmonary disease (COPD), defective macrophage phagocytic clearance of cells undergoing apoptosis by efferocytosis may lead to secondary necrosis of the uncleared cells and contribute to airway inflammation. The precise mechanisms for this phenomenon remain unknown. LC3-associated phagocytosis (LAP) is indispensable for effective efferocytosis. We hypothesized that cigarette smoke inhibits the regulators of LAP pathway, potentially contributing to the chronic airways inflammation associated with COPD. METHODS: Bronchoalveolar (BAL)-derived alveolar macrophages, lung tissue macrophages obtained from lung resection surgery, and monocyte-derived macrophages (MDM) were prepared from COPD patients and control participants. Lung/airway samples from mice chronically exposed to cigarette smoke were also investigated. Differentiated THP-1 cells were exposed to cigarette smoke extract (CSE). The LAP pathway including Rubicon, as an essential regulator of LAP, efferocytosis and inflammation was examined using western blot, ELISA, flow cytometry, and/or immunofluorescence. RESULTS: Rubicon was significantly depleted in COPD alveolar macrophages compared with non-COPD control macrophages. Rubicon protein in alveolar macrophages of cigarette smoke-exposed mice and cigarette smoke-exposed MDM and THP-1 was decreased with a concomitant impairment of efferocytosis. We also noted increased expression of LC3 which is critical for LAP pathway in COPD and THP-1 macrophages. Furthermore, THP-1 macrophages exposed to cigarette smoke extract exhibited higher levels of other key components of LAP pathway including Atg5 and TIM-4. There was a strong positive correlation between Rubicon protein expression and efferocytosis. CONCLUSION: LAP is a requisite for effective efferocytosis and an appropriate inflammatory response, which is impaired by Rubicon deficiency. Our findings suggest dysregulated LAP due to reduced Rubicon as a result of CSE exposure. This phenomenon could lead to a failure of macrophages to effectively process phagosomes containing apoptotic cells during efferocytosis. Restoring Rubicon protein expression has unrecognized therapeutic potential in the context of disease-related modifications caused by exposure to cigarette smoke.

Dysregulated zinc and sphingosine-1-phosphate signaling in pulmonary hypertension: Potential effects by targeting of bone morphogenetic protein receptor type 2 in pulmonary microvessels.

Recently identified molecular targets in pulmonary artery hypertension (PAH) include sphingosine-1-phosphate (S1P) and zinc transporter ZIP12 signaling. This study sought to determine linkages between these pathways, and with BMPR2 signaling. Lung tissues from a rat model of monocrotaline-induced PAH and therapeutic treatment with bone marrow-derived endothelial-like progenitor cells transduced to overexpress BMPR2 were studied. Multifluorescence quantitative confocal microscopy (MQCM) was applied for analysis of protein expression and localization of markers of vascular remodeling (αSMA and BMPR2), parameters of zinc homeostasis (zinc transporter SLC39A/ZIP family members 1, 10, 12 and 14; and metallothionein MT3) and S1P extracellular signaling (SPHK1, SPNS2, S1P receptor isoforms 1, 2, 3, 5) in 20-200 µm pulmonary microvessels. ZIP12 expression in whole lung tissue lysates was assessed by western blot. Spearman nonparametric correlations between MQCM readouts and hemodynamic parameters, Fulton index (FI), and right ventricular systolic pressure (RVSP) were measured. In line with PAH status, pulmonary microvessels in monocrotaline-treated animals demonstrated significant (p < .05, n = 6 per group) upregulation of αSMA (twofold) and downregulation of BMPR2 (20%). Upregulated ZIP12 (92%), MT3 (57.7%), S1PR2 (54.8%), and S1PR3 (30.3%) were also observed. Significant positive and negative correlations were demonstrated between parameters of zinc homeostasis (ZIP12, MT3), S1P signaling (S1PRs, SPNS2), and vascular remodeling (αSMA, FI, RVSP). MQCM and western blot analysis showed that monocrotaline-induced ZIP12 upregulation could be partially negated by BMPR2-targeted therapy. Our results indicate that altered zinc transport/storage and S1P signaling in the monocrotaline-induced PAH rat model are linked to each other, and could be alleviated by BMPR2-targeted therapy.

AIM2 nuclear exit and inflammasome activation in chronic obstructive pulmonary disease and response to cigarette smoke.

INTRODUCTION: The role inflammasomes play in chronic obstructive pulmonary disease (COPD) is unclear. We hypothesised that the AIM2 inflammasome is activated in the airways of COPD patients, and in response to cigarette smoke. METHODS: Lung tissue, bronchoscopy-derived alveolar macrophages and bronchial epithelial cells from COPD patients and healthy donors; lungs from cigarette smoke-exposed mice; and cigarette smoke extract-stimulated alveolar macrophages from healthy controls and HBEC30KT cell line were investigated. AIM2 inflammasome activation was assessed by multi-fluorescence quantitative confocal microscopy of speck foci positive for AIM2, inflammasome component ASC and cleaved IL-1ß. Subcellular AIM2 localization was assessed by confocal microscopy, and immunoblot of fractionated cell lysates. Nuclear localization was supported by in-silico analysis of nuclear localization predicted scores of peptide sequences. Nuclear and cytoplasmic AIM2 was demonstrated by immunoblot in both cellular fractions from HBEC30KT cells. RESULTS: Increased cytoplasmic AIM2 speck foci, colocalized with cleaved IL-1ß, were demonstrated in COPD lungs (n = 9) vs. control (n = 5), showing significant positive correlations with GOLD stages. AIM2 nuclear-to-cytoplasmic redistribution was demonstrated in bronchiolar epithelium in cigarette-exposed mice and in HBEC30KT cells post 24 h stimulation with 5% cigarette smoke extract. Alveolar macrophages from 8 healthy non-smokers responded to cigarette smoke extract with an > 8-fold increase (p < 0.05) of cytoplasmic AIM2 and > 6-fold increase (p < 0.01) of colocalized cleaved IL-1ß speck foci, which were also localized with ASC. CONCLUSION: The AIM2 inflammasome is activated in the airway of COPD patients, and in response to cigarette smoke exposure, associated with a nuclear to cytoplasmic shift in the distribution of AIM2.

The role of oxidised self-lipids and alveolar macrophage CD1b expression in COPD.

In chronic obstructive pulmonary disease (COPD) apoptotic bronchial epithelial cells are increased, and their phagocytosis by alveolar macrophages (AM) is decreased alongside bacterial phagocytosis. Epithelial cellular lipids, including those exposed on uncleared apoptotic bodies, can become oxidized, and may be recognized and presented as non-self by antigen presenting cells. CD1b is a lipid-presenting protein, previously only described in dendritic cells. We investigated whether CD1b is upregulated in COPD AM, and whether lipid oxidation products are found in the airways of cigarette smoke (CS) exposed mice. We also characterise CD1b for the first time in a range of macrophages and assess CD1b expression and phagocytic function in response to oxidised lipid. Bronchoalveolar lavage and exhaled breath condensate were collected from never-smoker, current-smoker, and COPD patients and AM CD1b expression and airway 8-isoprostane levels assessed. Malondialdehyde was measured in CS-exposed mouse airways by confocal/immunofluorescence. Oxidation of lipids produced from CS-exposed 16HBE14o- (HBE) bronchial epithelial cells was assessed by spectrophotometry and changes in lipid classes assessed by mass spectrometry. 16HBE cell toxicity was measured by flow cytometry as was phagocytosis, CD1b expression, HLA class I/II, and mannose receptor (MR) in monocyte derived macrophages (MDM). AM CD1b was significantly increased in COPD smokers (4.5 fold), COPD ex-smokers (4.3 fold), and smokers (3.9 fold), and AM CD1b significantly correlated with disease severity (FEV1) and smoking pack years. Airway 8-isoprostane also increased in smokers and COPD smokers and ex-smokers. Malondialdehyde was significantly increased in the bronchial epithelium of CS-exposed mice (MFI of 18.18 vs 23.50 for control). Oxidised lipid was produced from CS-exposed bronchial epithelial cells (9.8-fold of control) and showed a different overall lipid makeup to that of control total cellular lipid. This oxidised epithelial lipid significantly upregulated MDM CD1b, caused bronchial epithelial cell toxicity, and reduced MDM phagocytic capacity and MR in a dose dependent manner. Increased levels of oxidised lipids in the airways of COPD patients may be responsible for reduced phagocytosis and may become a self-antigen to be presented by CD1b on macrophages to perpetuate disease progression despite smoking cessation.

Prediction of VO2max based on a 3-kilometer running test for water sports athletes.

BACKGROUND: No studies have reported the 3-kilometer running test (3KRT) intending to predict VO2max for water sports athletes. Therefore, the purpose of this study was to develop a new model to predict the maximal aerobic capacity (VO2max) for water sports athletes based on 3KRT. METHODS: One hundred and two water sports athletes completed two sessions of experiments consisting of a maximal graded exercise test (GXT) and a 3KRT. Multiple linear regression was applied to predict VO2max value based on the performance and physiological responses of 3KRT, along with participants' anthropometric and demographic variables. The predicted residual error sum of square (PRESS) and error terms (constant error and total error) were calculated to further evaluate the predictive accuracy. RESULTS: Two significant prediction models based on elapsed exercise time (T3KRT), post-exercise heart rate (PHR3KRT), body mass, and gender were proposed. One model including PHR3KRT was identified (VO2max=120.77-0.028×T3KRT [second]-0.11×PHR3KRT [bpm]-0.334×body mass [kg]+8.70×gender [1: male, 0: female]), with an adjusted R2 of 0.723. Another model excluding PHR3KRT was also identified (VO2max=103.65-0.034×T3KRT [second]-0.317×Body mass [kg] + 7.89×gender [1: male, 0: female]), with an adjusted R2 of 0.713. Both models were further validated by the result of PRESS statistics. CONCLUSIONS: This endurance 3-kilometer running test accurately predicted VO2max value for water sports athletes (rowers, canoeists, and kayakers), and the model excluding PHR3KRT would be easier to use.

LC3-Associated Phagocytosis (LAP): A Potentially Influential Mediator of Efferocytosis-Related Tumor Progression and Aggressiveness.

One aim of cancer therapies is to induce apoptosis of tumor cells. Efficient removal of the apoptotic cells requires coordinated efforts between the processes of efferocytosis and LC3-associated phagocytosis (LAP). However, this activity has also been shown to produce anti-inflammatory and immunosuppressive signals that can be utilized by live tumor cells to evade immune defense mechanisms, resulting in tumor progression and aggressiveness. In the absence of LAP, mice exhibit suppressed tumor growth during efferocytosis, while LAP-sufficient mice show enhanced tumor progression. Little is known about how LAP or its regulators directly affect efferocytosis, tumor growth and treatment responses, and identifying the mechanisms involved has the potential to lead to the discovery of novel approaches to target cancer cells. Also incompletely understood is the direct effect of apoptotic cancer cells on LAP. This is particularly important as induction of apoptosis by current cytotoxic cancer therapies can potentially stimulate LAP following efferocytosis. Herein, we highlight the current understanding of the role of LAP and its relationship with efferocytosis in the tumor microenvironment with a view to presenting novel therapeutic strategies.

Interventional low-dose azithromycin attenuates cigarette smoke-induced emphysema and lung inflammation in mice.

Cigarette smoke (CS)-induced emphysema is an important contributor to chronic obstructive pulmonary disease (COPD). We have shown the efficacy of azithromycin in reducing airway inflammation in COPD and in reducing exacerbations in severe asthma; however, the effects of long-term azithromycin on emphysema development have not been shown. We employed live animal imaging to monitor emphysema-like development and the effects of interventional azithromycin treatment in CS-exposed mice. BALB/c mice (female, 10 weeks; n = 10) were exposed to CS for 1 hr twice daily, 5 days/week, and for 12 weeks (CS). Half were cotreated with low-dose azithromycin during weeks 7-12 (CS + Azi; 0.2 mg kg-1  day-1 ). Microcomputed tomography (CT) and magnetic resonance imaging (MRI) scans were acquired longitudinally. Histological examinations were performed post mortem (mean linear intercept (Lm) and leukocyte infiltration). CS increased median Lm (CS: 42.45 µm versus control: 34.7 µm; p = .0317), this was recovered in CS + Azi mice (33.03 µm). Average CT values were reduced in CS mice (CS: -399.5 Hounsfield units (HU) versus control: -384.9 HU; p = .0286) but not in CS + Azi mice (-377.3 HU). CT values negatively correlated with Lm (r = -.7972; p = .0029) and T2 -weighted MRI (r = -.6434; p = .0278). MRI also showed significant CS-induced inflammatory changes that were attenuated by azithromycin in the lungs, and positively correlated with Lm (r = .7622; p = .0055) and inflammatory foci counts (r = .6503; p = .0257). Monitoring of emphysema development is possible via micro-CT and MRI. Interventional azithromycin treatment in CS-exposed mice attenuated the development of pulmonary emphysema-like changes.

Enhanced inflammasome activation and reduced sphingosine-1 phosphate S1P signalling in a respiratory mucoobstructive disease model.

BACKGROUND: Inflammasomes and sphingosine-1-phosphate (S1P) signalling are increasingly subject to intensive research in human diseases. We hypothesize that in respiratory muco-obstructive diseases, mucus obstruction enhances NLRP3 inflammasome activation and dysregulated S1P signalling. METHODS: Lung tissues from mice overexpressing the beta-unit of the epithelial sodium channel (ßENaC) and their littermate controls were examined by histology, immunofluorescence and confocal microscopy, followed by ImageJ quantitative analysis. RESULTS: Lower airways in ßENaC mice showed patchy patterns of mucus obstruction and neutrophil-dominant infiltrations. In contrast to a ubiquitous distribution of TNFα specks, significantly (p < 0.05) increased specks of bronchiolar NLRP3, IL-1ß, and IgG in the ßENaC mouse lungs were localized to the vicinity of mucus obstruction sites. Bright Spinster homologue 2 (SPNS2) at the epithelial apex and positive correlation with sphingosine kinase 1 (SPHK1) (R2 = 0.640; p < 0.001) supported the normal bronchial epithelium as an active generator of extracellular S1P. SPNS2 in ßENaC mice was sharply reduced (38%, p < 0.05) and lost apical localization at sites of mucus obstruction. A significant (34%; p < 0.01) decrease in epithelial SPHK2 was also noted at mucus obstruction sites. CONCLUSION: These results support that mucus obstruction may enhance NLRP3 inflammasome activation and dysregulated S1P signaling.

Lymphocyte senescence in COPD is associated with decreased sirtuin 1 expression in steroid resistant pro-inflammatory lymphocytes.

BACKGROUND: The class III NAD-dependent histone deacetylase (HDAC) sirtuin 1 (SIRT1) is an important regulator of senescence, aging, and inflammation. SIRT1de-acetylates chromatin histones, thereby silencing inflammatory gene transcription. We have reported increased steroid-resistant senescent pro-inflammatory CD28nullCD8+ T cells in patients with chronic obstructive pulmonary disease (COPD). We hypothesized that SIRT1 is reduced in these cells in COPD, and that treatment with SIRT1 activators (resveratrol, curcumin) and agents preventing NAD depletion (theophylline) would upregulate SIRT1 and reduce pro-inflammatory cytokine expression in these steroid-resistant cells. METHODS: Blood was collected from n = 10 COPD and n = 10 aged-matched controls. Expression of CD28, SIRT1, and pro-inflammatory cytokines was determined in CD8+ and CD8- T and natural killer T (NKT)-like cells cultured in the presence of ±1 µM prednisolone, ±5 mg/L theophylline, ±1 µM curcumin, ±25 µM resveratrol, using flow cytometry and immunofluorescence. RESULTS: There was an increase in the percentage of CD28nullCD8+ T and NKT-like cells in COPD patients compared with controls. Decreased SIRT1 expression was identified in CD28nullCD8+T and NKT-like cells compared with CD28+ counterparts from both patients and controls (e.g. CD28null 11 ± 3% versus CD28+ 57 ± 9%). Loss of SIRT1 was associated with increased production of IFNγ and TNFα, steroid resistance, and disease severity. SIRT1 expression was upregulated in the presence of all drugs and was associated with a decrease in steroid resistance and IFNγ and TNFα production by CD28nullCD8+T and NKT-like cells. The presence of the SIRT1 inhibitor, EX-527 negated [by 92 ± 12% (median ± SEM)] the effect of the SIRT1 activator SRT720 on the percentage of CD8+ T cells producing IFNγ and TNFα. CONCLUSIONS: Steroid resistance in pro-inflammatory CD28nullCD8+ T and NKT-like cells is associated with decreased SIRT1 expression. Treatment with prednisolone, in combination with theophylline, curcumin or resveratrol increases SIRT1 expression, restores steroid sensitivity, and inhibits pro-inflammatory cytokine production from these cells and may reduce systemic inflammation in COPD. The reviews of this paper are available via the supplemental material section.

Tempol alleviates chronic intermittent hypoxia-induced pancreatic injury through repressing inflammation and apoptosis.

Obstructive sleep apnea (OSA) has been demonstrated to be implicated in disorder of insulin secretion and diabetes mellitus. In this study, we aimed to evaluate the protective role of tempol, a powerful antioxidant, in chronic intermittent hypoxia (IH)-induced pancreatic injury. The rat model of OSA was established by IH exposure. The pathological changes, increased blood-glucose level, and raised proinsulin/insulin ratio in pancreatic tissues of rats received IH were effectively relieved by tempol delivery. In addition, the enhanced levels of pro-inflammatory cytokines, TNF-alpha, IL-1beta, IL-6, and inflammatory mediators, PGE2, cyclooxygenase-2 (COX-2), NO, and inducible nitric oxide synthase (iNOS) in pancreatic tissue were suppressed by tempol. Moreover, tempol inhibited IH-induced apoptosis in pancreatic tissue as evidenced by upregulated Bcl-2 level, and downregulated Bax and cleaved caspase-3 levels. Finally, the abnormal activation of mitogen-activated protein kinase (MAPK) and nuclear factor kappa-light-chain-enhancer of activated B cells (NF-kappaB) signaling pathways induced by IH was restrained by tempol administration. In summary, our study demonstrates that tempol relieves IH-induced pancreatic injury by inhibiting inflammatory response and apoptosis, which provides theoretical basis for tempol as an effective treatment for OSA-induced pancreatic injury.

Distribution characteristics and health risk assessment of heavy metals and PAHs in the soils of green spaces in Shanghai, China.

The environmental sustainability of megacities is a global problem, and megacities are experiencing increasing pressure and challenges with regard to providing a suitable living environment for people. Urban green space plays a crucial role in protecting urban ecological environments and in maintaining the physical and mental health of residents. In this study, a total of 94 soil samples from green spaces in Shanghai, including park green spaces and road green spaces in the eight central urban districts, were collected, and the contents of heavy metals and polycyclic aromatic hydrocarbons (PAHs) were analyzed to determine the distribution characteristics and influencing factors and to assess the associated health risks. The accumulation of heavy metals was greater in park green space soils than in road green space soils, although the variation coefficient of the former was lower than that of the latter. Conversely, the accumulation of PAHs was lower in park green space soils than that in road green space soils, although the variation coefficient of the former was higher than that of the latter. In particular, Cu, Zn, Pb, Cd, As, and PAHs have accumulated in Shanghai green space soils. With increasing soil depth (0-2 cm, 2-5 cm, 5-10 cm, and 10-30 cm), the PAH content increased in the park green space soils but decreased in the road green space soils. According to the "Technical guidelines for risk assessment of contaminated sites (MEP of China 2014)," the overall health risk posed by green space soils in urban areas in Shanghai can be considered safe, except at individual sampling sites. The PAH, Cu, and Zn contents of park green space soils might be related to the application of organic materials and to traffic and industry emissions. However, the soil pollutants in road green spaces are predominantly related to traffic and industrial emissions. Therefore, the monitoring and management of soil environmental quality must be strengthened.

Prevalence and Factors Associated With Bone Erosion in Patients With Gout.

OBJECTIVE: To determine the prevalence, distribution, and factors associated with bone erosion detectable by ultrasound in patients with gout. METHODS: Ultrasound scans were performed in 980 patients with gout, and bone erosion was detected. The prevalence and distribution of bone erosion in gout patients were calculated. Both clinical variables and ultrasound signs were entered into a multivariate logistic regression analysis to clarify the factors associated with bone erosion in patients with gout. RESULTS: Bone erosion was found in 431 (44.0%) of the 980 patients with gout, and in 338 (78.4%) of these patients, the bone erosion was found in the first metatarsophalangeal (MTP) joint. A multivariable logistic regression analysis showed that age, duration of gout, the existence of tophi, ultrasound-detected synovial hypertrophy, and joint effusion were independently associated with bone erosion. A tophus was the most powerful factor associated with bone erosion, with an odds ratio (OR) of 4.218 (95% confidence interval 3.092-5.731). The risk for bone erosion also increased as the number of tophi increased (P < 0.001). However, after stratifying the size of tophi, the ORs did not increase significantly (P = 0.206). CONCLUSION: A high percentage of gout patients had bone erosions; the first MTP joint was the most frequently involved site. Age, duration of gout, tophi, and synovial hypertrophy were factors associated with bone erosion in gout patients. The number of tophi, but not their size, was strongly associated with bone erosion in patients with gout.

Bushfire smoke is pro-inflammatory and suppresses macrophage phagocytic function.

Bushfires are increasing in frequency and severity worldwide. Bushfire smoke contains organic/inorganic compounds including aldehydes and acrolein. We described suppressive effects of tobacco smoke on the phagocytic capacity of airway macrophages, linked to secondary necrosis of uncleared apoptotic epithelial cells, persistence of non-typeable H. influenzae (NTHi), and inflammation. We hypothesised that bushfire smoke extract (BFSE) would similarly impair macrophage function. THP-1 or monocyte-derived macrophages (MDM) were exposed to 1-10% BFSE prepared from foliage of 5 common Australian native plants (genus Acacia or Eucalyptus), or 10% cigarette smoke extract (CSE). Phagocytic recognition receptors were measured by flow cytometry; pro-inflammatory cytokines and caspase 1 by immunofluorescence or cytometric bead array; viability by LDH assay; and capsase-3/PARP by western blot. BFSE significantly decreased phagocytosis of apoptotic cells or NTHi by both THP-1 macrophages and MDM vs air control, consistent with the effects of CSE. BFSE significantly decreased MDM expression of CD36, CD44, SR-A1, CD206 and TLR-2 and increased active IL-1ß, caspase-1 and secreted IL-8. BFSE dose-dependently decreased THP-1 macrophage viability (5-fold increase in LDH at 10%) and significantly increased active caspase-3. BFSE impairs macrophage function to a similar extent as CSE, highlighting the need for further research, especially in patients with pre-existing lung disease.

Simple method for liquid analysis by laser-induced breakdown spectroscopy (LIBS).

As a fast-developing technique for in situ multi-element analysis method, laser induced breakdown spectroscopy - LIBS is, however, developing slowly on liquid analysis due to some technical difficulties. We propose a new method, namely capillary mode, to quantify the concentrations of the elements in solution using LIBS. A Nd:YAG laser with repetition of 10 Hz were used to analyze the solution of Na2CrO4 and no any sample preparation in measurements. The experimental results show that the splashing of liquid induced by laser pulses is decreased significantly and the pollution of mirrors is avoided effectively using liquid capillary mode. The results of quantitative analysis for liquid are also improved than other method. The calibration curves of Cr and Na are well characterized by straight lines and the regression coefficient values of the linear fit are better than 0.998. The limits of detection (LODs) of Cr and Na are determined to be 28.9 mg/L and 1.0 mg/L in this work, respectively. The experimental results show that the liquid capillary mode provides a more practical and very simple approach to improve accuracy of quantitative element analysis in liquids by LIBS technique.

Design rules of heteroatom-doped graphene to achieve high performance lithium-sulfur batteries: Both strong anchoring and catalysing based on first principles calculation.

A number of observations have been reported on chemical capture and catalysis of anchoring materials for lithium-sulfur batteries. Here, we propose the design principles for the chemical functioned graphene as an anchor material to realize both strong chemical trapping and catalysis. Through the first principle, the periodic law is calculated from the theory. Seven different co-doping series were investigated, e.g. MN4@graphene (M = V, Cr, Mn, Fe, Co, Ni, and Cu). From binding energy, partial density of state, and charge density difference analysis, the FeN4 and CrN4 co-doped graphene show good performance for the lithium-sulfur battery from both strong anchoring and catalytic effects. For the most kinds of Li2Sx (x = 1, 2, 4, 6, 8) absorption, two combinations can be achieved, including S-bonding and Li-bonding. The competition between the MS and the NLi shows the main difference of the co-doped configurations. Moreover, the S-bonding systems have better performance for both moderate chemical trapping and strong catalysis. The binding energies of Li2Sx and Li decomposed properties considered as the key descriptors for the rational design of lithium-sulfur battery. Lastly, we offer design rules for high performance lithium-sulfur batteries based on the chemical functional graphene materials.

Multiple inflammasomes may regulate the interleukin-1-driven inflammation in protracted bacterial bronchitis.

Protracted bacterial bronchitis (PBB) in young children is characterised by prolonged wet cough, prominent airway interleukin (IL)-1ß expression and infection, often with nontypeable Haemophilus influenzae (NTHi). The mechanisms responsible for IL-1-driven inflammation in PBB are poorly understood. We hypothesised that the inflammation in PBB involves the NLRP3 and/or AIM2 inflammasome/IL-1ß axis. Lung macrophages obtained from bronchoalveolar lavage (BAL), peripheral blood mononuclear cells (PBMCs), blood monocytes and monocyte-derived macrophages from patients with PBB and age-matched healthy controls were cultured in control medium or exposed to live NTHi. In healthy adult PBMCs, CD14+ monocytes contributed to 95% of total IL-1ß-producing cells upon NTHi stimulation. Stimulation of PBB PBMCs with NTHi significantly increased IL-1ß expression (p<0.001), but decreased NLRC4 expression (p<0.01). NTHi induced IL-1ß secretion in PBMCs from both healthy controls and patients with recurrent PBB. This was inhibited by Z-YVAD-FMK (a caspase-1 selective inhibitor) and by MCC950 (a NLRP3 selective inhibitor). In PBB BAL macrophages inflammasome complexes were visualised as fluorescence specks of NLRP3 or AIM2 colocalised with cleaved caspase-1 and cleaved IL-1ß. NTHi stimulation induced formation of specks of cleaved IL-1ß, NLRP3 and AIM2 in PBMCs, blood monocytes and monocyte-derived macrophages. We conclude that both the NLRP3 and AIM2 inflammasomes probably drive the IL-1ß-dominated inflammation in PBB.

Disrupted epithelial/macrophage crosstalk via Spinster homologue 2-mediated S1P signaling may drive defective macrophage phagocytic function in COPD.

INTRODUCTION: We have previously established a link between impaired phagocytic capacity and deregulated S1P signaling in alveolar macrophages from COPD subjects. We hypothesize that this defect may include a disruption of epithelial-macrophage crosstalk via Spns2-mediated intercellular S1P signaling. METHODS: Primary alveolar macrophages and bronchial epithelial cells from COPD subjects and controls, cell lines, and a mouse model of chronic cigarette smoke exposure were studied. Cells were exposed to 10% cigarette smoke extract, or vehicle control. Spns2 expression and subcellular localization was studied by immunofluorescence, confocal microscopy and RT-PCR. Phagocytosis was assessed by flow-cytometry. Levels of intra- and extracellular S1P were measured by S1P [3H]-labeling. RESULTS: Spns2 expression was significantly increased (p<0.05) in alveolar macrophages from current-smokers/COPD patients (n = 5) compared to healthy nonsmokers (n = 8) and non-smoker lung transplant patients (n = 4). Consistent with this finding, cigarette smoke induced a significant increase in Spns2 expression in both human alveolar and THP-1 macrophages. In contrast, a remarkable Spns2 down-regulation was noted in response to cigarette smoke in 16HBE14o- cell line (p<0.001 in 3 experiments), primary nasal epithelial cells (p<0.01 in 2 experiments), and in smoke-exposed mice (p<0.001, n = 6 animals per group). Spns2 was localized to cilia in primary bronchial epithelial cells. In both macrophage and epithelial cell types, Spns2 was also found localized to cytoplasm and the nucleus, in line with a predicted bipartile Nuclear Localization Signal at the position aa282 of the human Spns2 sequence. In smoke-exposed mice, alveolar macrophage phagocytic function positively correlated with Spns2 protein expression in bronchial epithelial cells. CONCLUSION: Our data suggest that the epithelium may be the major source for extracellular S1P in the airway and that there is a possible disruption of epithelial/macrophage cross talk via Spns2-mediated S1P signaling in COPD and in response to cigarette smoke exposure.