Association of CLDN molecules with sleep apnea hypopnea syndrome: new biomarker candidates.

Introduction: Obstructive sleep apnea (OSA) is a common sleep-related breathing disorder, and has become a serious threat to public health. Intermittent hypoxia caused by OSA results in a low-grade inflammatory response that leads to impaired mucosal barrier function. Claudin (CLDN) molecules are important for the permeability of the mucosal epithelium. This study aimed to explore whether CLDN molecules can be a potential biomarker of OSA. Methods: A total of 37 healthy controls and 40 OSA patients underwent a physical assessment for OSA and filled out the STOP-Bang Questionnaire (SBQ) and Epworth Sleepiness Scale (ESS). Clinical specimens of plasma and urine were obtained to observe the difference between OSA patients and healthy controls and diagnostic accuracy of CLDN molecules for OSA. Results: CLDN1, CLDN2, and CLDN3 molecules in plasma and urine decreased in OSA patients (both p < 0.05). The areas under the receiver operating characteristic curve (AUCs) of urinary CLDN1, plasma CLDN1, urinary CLDN2, plasma CLDN2, urinary CLDN3, and plasma CLDN3 were 0.887, 0.724, 0.779, 0.676, 0.828, and 0.665, respectively. The AUC of urinary CLDN1 + CLDN2 + CLDN3 was 0.906 (95% confidence interval (CI), 0.831-0.981). The AUC of plasma CLDN1 + CLDN2 + CLDN3 was 0.776 (95% CI, 0.645-0.878). The AUC of urinary CLDN3 + SBQ was 0.899 (95% CI, 0.832-0.967). The AUC of urinary CLDN3 + ESS was 0.896 (95% CI, 0.826-0.966). In addition, Urinary CLDN-3 was negative associated with the severity of OSA. Conclusion: CLDN molecules are promising as useful biomarkers for OSA, which may be related to the impaired barrier function related to OSA.

Chinese expert consensus on cone-beam CT-guided diagnosis, localization and treatment for pulmonary nodules.

Cone-beam computed tomography (CBCT) system can provide real-time 3D images and fluoroscopy images of the region of interest during the operation. Some systems can even offer augmented fluoroscopy and puncture guidance. The use of CBCT for interventional pulmonary procedures has grown significantly in recent years, and numerous clinical studies have confirmed the technology's efficacy and safety in the diagnosis, localization, and treatment of pulmonary nodules. In order to optimize and standardize the technical specifications of CBCT and guide its application in clinical practice, the consensus statement has been organized and written in a collaborative effort by the Professional Committee on Interventional Pulmonology of China Association for Promotion of Health Science and Technology.

Bronchoscopic instillation of amphotericin B is a safe and effective measure to treat pulmonary mycosis.

Background and objectives: In recent years, there has been a significant increase in the prevalence of pulmonary mycosis disease, and its mortality has increased. There are very few studies on treating pulmonary mycosiss with bronchoscopic instillation of amphotericin B. This study investigated the clinical efficacy and safety of bronchoscopic instillation of amphotericin B for treating pulmonary mycosiss. Methods: This was a multi-centre, retrospective clinical study of 80 patients with pulmonary mycosiss who were treated with bronchoscopic instillation of amphotericin B. The efficacy and safety of this treatment were evaluated. Results: Eighty patients were included {51 males; mean [standard deviation (SD)] age, 46 (15.9) years}. The most common underlying cause was haematological malignancy (73.75%). The mean number of bronchoscopic instillations of amphotericin B was 2.4 (SD 1.5). In terms of treatment success, 58 (72.5%) patients achieved complete or partial changes on imaging after treatment. A total of 62 (77.5%) patients achieved complete or partial changes on imaging and/or local limitation of the mycosis infection. Seventy-six (95%) patients achieved complete or partial changes on imaging and/or local limitation of mycosis infection and/or an immunotherapy time window. The efficacy rates for treatment of Aspergillus and Mucor infections in terms of the three treatment success criteria described above were 73.81% vs. 63.64%, 80.95% vs. 72.73%, and 92.86% vs. 90.91%, respectively. Conclusion: Bronchoscopic instillation of amphotericin B is safe and effective for treatment of pulmonary mycosiss.

Potential biomarkers for diagnosis and disease evaluation of idiopathic pulmonary fibrosis.

ABSTRACT: Idiopathic pulmonary fibrosis (IPF) is a chronic progressive lung disease characterized by progressive lung fibrogenesis and histological features of usual interstitial pneumonia. IPF has a poor prognosis and presents a spectrum of disease courses ranging from slow evolving disease to rapid deterioration; thus, a differential diagnosis remains challenging. Several biomarkers have been identified to achieve a differential diagnosis; however, comprehensive reviews are lacking. This review summarizes over 100 biomarkers which can be divided into six categories according to their functions: differentially expressed biomarkers in the IPF compared to healthy controls; biomarkers distinguishing IPF from other types of interstitial lung disease; biomarkers differentiating acute exacerbation of IPF from stable disease; biomarkers predicting disease progression; biomarkers related to disease severity; and biomarkers related to treatment. Specimen used for the diagnosis of IPF included serum, bronchoalveolar lavage fluid, lung tissue, and sputum. IPF-specific biomarkers are of great clinical value for the differential diagnosis of IPF. Currently, the physiological measurements used to evaluate the occurrence of acute exacerbation, disease progression, and disease severity have limitations. Combining physiological measurements with biomarkers may increase the accuracy and sensitivity of diagnosis and disease evaluation of IPF. Most biomarkers described in this review are not routinely used in clinical practice. Future large-scale multicenter studies are required to design and validate suitable biomarker panels that have diagnostic utility for IPF.

The efficacy and mechanism of thoracic photodynamic therapy mediated by hematoporphyrin injection on disseminated pleural malignancies of Lewis lung carcinoma in mice.

In order to avoid the problems of long exposure time and high incidence of photosensitivity by intravenous injection of photosensitizer, our study explore the safety, efficacy, and possible mechanisms of photodynamic therapy (PDT) by intrathoracic administration of hematoporphyrin injection in the treatment of disseminated pleural malignancies of Lewis lung carcinoma in mice to provide a theoretical basis for thoracic PDT in the clinic. Hematoporphyrin was administered into the thoracic cavity of tumor-bearing mice, and the concentrations of hematoporphyrin in normal and tumor pleural tissues were detected by high-performance liquid chromatography. The tumor-bearing mice were randomly divided into four groups: model control, pure laser irradiation, PDT low-dose, and PDT high-dose groups. Hematoxylin and eosin (H&E) staining was used to observe the histological changes in normal pleural tissue. H&E and DNA in situ nick end-labeling staining were used to detect necrosis and apoptosis in the tumor tissues. The tumor volume in each group from high to low was as follows: model control group > pure laser irradiation group > PDT low-dose group > PDT high-dose group. Inflammatory cells infiltrated the normal pleural tissue of the PDT group. Necrosis was observed to different extents in the tumor tissues of the PDT group. The apoptosis index of each group from high to low was as follows: PDT high-dose group > PDT low-dose group > pure laser irradiation group > model control group. The differences were statistically significant (P<0.05). Hematoporphyrin selectively accumulated in tumor pleural tissues. PDT with intrathoracic administration of hematoporphyrin injection could inhibit the thoracic implant tumors in mice by inducing necrosis and apoptosis.

Effect of curcumin on lung epithelial injury and ferroptosis induced by cigarette smoke.

Cigarette smoke (CS)-caused ferroptosis was involved in the pathogenesis of COPD, but the role of ferroptosis in lung epithelial injury and inflammation is not clear. Rats were treated with CS or CUR and BEAS-2B cells were exposed to CS extract (CSE), ferrostatin-1 (Fer-1), deferoxamine (DFO), or CUR to detect reactive oxygen species (ROS) accumulation, lipid peroxidation, iron overload, and ferroptosis-related protein, which were the characteristic changes of ferroptosis. Compared with the control group, CSE-treated BEAS-2B cells had more cell death, higher cytotoxicity, and lower cell viability. The infiltration of inflammatory cell around the bronchi in the CS group of rats was more than that in the normal group. Meanwhile, CSE/CS elevated the levels of interleukin-6 and tumor necrosis factor-α in BEAS-2B cells and bronchoalveolar lavage fluid of rats. Besides, accumulative ROS and depleted glutathione was observed in vitro. In BEAS-2B cells and lung tissues of rats, CSE/CS increased malondialdehyde and iron; down-regulated solute carrier family 7, glutathione peroxidase 4, and ferritin heavy chain levels; and up-regulated transferrin receptor level. These changes were rescued by pretreatment of Fer-1 or DFO in vitro, and mitigated by CUR in vitro and in vivo. Collectively, this study reveals that ferroptosis was involved in lung epithelial cell injury and inflammation induced by CS, and CUR may alleviate CS-induced injury, inflammation, and ferroptosis of lung epithelial cell.

Curcumin induces ferroptosis in non-small-cell lung cancer via activating autophagy.

BACKGROUND: Emerging studies showed curcumin can inhibit glioblastoma and breast cancer cells via regulating ferroptosis. However, the role of ferroptosis in the inhibitory effect of curcumin on non-small-cell lung cancer (NSCLC) remains unclear. METHODS: Cell counting kit-8 (CCK-8) assay was used to measure the viability of A549 and H1299 cells under different conditions. Cell proliferation was examined by Ki67 immunofluorescence. The morphological changes of cells and tumor tissues were observed by optical microscope and hematoxylin and eosin (H&E) staining. Intracellular reactive oxygen species (ROS), malondialdehyde (MDA), superoxide dismutase (SOD), glutathione (GSH), and iron contents were determined by corresponding assay kit. The related protein expression levels were detected by western blot and immunohistochemistry. Transmission electron microscope was used to observe ultrastructure changes of A549 and H1299 cells. RESULTS: Curcumin inhibited tumor growth and cell proliferation, but promoted cell death. Characteristic changes of ferroptosis were observed in curcumin group, including iron overload, GSH depletion and lipid peroxidation. Meanwhile, the protein level of ACSL4 was higher and the levels of SLC7A11 and GPX4 were lower in curcumin group than that in control group. Incubation of ferroptosis inhibitors ferrostatin-1 (Fer-1) or knockdown of iron-responsive element-binding protein 2 (IREB2) notably weakened curcumin-induced anti-tumor effect and ferroptosis in A549 and H1299 cells. Further investigation suggested that curcumin induced mitochondrial membrane rupture and mitochondrial cristae decrease, increased autolysosome, increased the level of Beclin1 and LC3, and decreased the level of P62. Curcumin-induced autophagy and subsequent ferroptosis were both alleviated with autophagy inhibitor chloroquine (CQ) or siBeclin1. CONCLUSION: Curcumin induced ferroptosis via activating autophagy in NSCLC, which enhanced the therapeutic effect of NSCLC.

Influence of coexistence of mild OSA on airway mucus hypersecretion in patients with COPD.

The coexistence of chronic obstructive pulmonary disease (COPD) and obstructive sleep apnea (OSA) can cause multiple system damage, and the main physiological mechanisms are continuous hypoxia and intermittent hypoxia (IH). Airway mucus hypersecretion is an important clinical feature of COPD, which can cause a progressive decline of lung function, acute COPD aggravation, and disease progression. The purpose of our study is to determine the influence of the coexistence of mild OSA on airway mucus hypersecretion. Clinical data and airway epithelial samples of 36 subjects were collected. The average fluorescence intensity of MUC5AC and the number of goblet cells were measured through immunofluorescence staining. MUC5AC expression was measured in human bronchial epithelial (HBE) cells exposed to normoxia, IH, particulate matter (PM), and PM + IH using real-time quantitative polymerase chain reaction and western blotting. FEV1% pred and FEV1/FVC were higher in patients with COPD-OSA overlap syndrome (OS) than in patients with COPD alone. Patients with OS had less sputum volume than patients with COPD alone. MUC5AC expression and the number of goblet cells in the airway epithelium in the COPD alone group were significantly higher than those in the OS groups. The PM + IH group had lower MUC5AC mRNA and protein expression in HBE cells than the PM group. The coexistence of mild OSA may reduce goblet cell proliferation and MUC5AC expression in the airway epithelium of patients with COPD. Mild IH inhibited PM-induced up-regulation of MUC5AC expression in the mRNA and protein levels in HBE cells.

Slow-wave sleep is associated with incident hypertension in patients with obstructive sleep apnea: a cross-sectional study.

OBJECTIVE: This study aimed to examine the association between slow-wave sleep ([SWS] N3 stage) and the risk of hypertension in patients with obstructive sleep apnea (OSA) or primary snorers. METHODS: A retrospective cross-sectional study of 1145 participants who were evaluated for suspected OSA at our Sleep Medical Center were included. Among these participants, 1022 had OSA and 123 were primary snorers. Logistic regression modeling was performed to evaluate the association between the prevalence of hypertension and combined OSA and SWS based on polysomnographic measurements. RESULTS: Patients with OSA in the lowest SWS quartile (quartile 1, < 2.0%) showed a two-fold increased risk of hypertension after adjustment for confounding factors compared with primary snorers (odds ratio, 2.13 [95% confidence interval 1.54-2.06]). In logistic analysis stratified according to SWS quartiles, there was no significant difference in the risk of hypertension between patients with OSA and primary snorers in quartile 1. However, in the highest quartile (quartile 4), SWS was significantly associated with incident hypertension in patients with OSA rather than primary snorers. CONCLUSION: SWS is associated with prevalent hypertension in patients with OSA. Notably, a low proportion of SWS confers a stronger association with incident hypertension than OSA.

A case of an immunocompetent young man obtaining community-acquired disseminated Nocardia brasiliensis.

Nocardiosis is a rare but severe pyogenic or granulomatous disease and caused by Nocardia that mainly infects immunocompromised patients. We report here a case of an immunocompetent 24-year-old male student with community-acquired pneumonia with asymptomatic disseminated cerebral abscess by Brasiliensis nocardiosis. The patient was fully recovered after receiving optimized antimicrobial therapy without relapse. This case suggests the health professionals such as the physicians of pulmonary, infection, neurology department and et al should always think about unusual cause of community acquired pneumonia, even in immunocompetent patients and when having pulmonary nocardiosis we should do a radiological neurological work up, even with the absence of neurological finding or symptom.

[Impact of chronic intermittent hypoxia upon rat liver lipid metabolism and interventional effect of Tempol].

OBJECTIVE: To explore the impact of chronic intermittent hypoxia (CIH) upon rat liver lipid metabolism and effect of anti-oxidant Tempol. METHODS: Male Wistar rats (n = 80) were randomly divided into intermittent hypoxia group (10, 20, 30, 40 times/h), intermittent hypoxia Tempol treatment group, intermittent hypoxia normal saline treatment group, intermittent air mimic group (IA) and blank control group (CG). Sections of liver were stained with hematoxylin and eosin. Serum levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were measured. Levels of liver homogenate triglyceride (TG), total cholesterol (TC), free fatty acids (FFA) and serum TG, TC, adiponectin (ADP) were measured. RESULTS: Liver histology: IH group exhibited hepatocellular swelling, hyperchromatosis, disrupted hepatocellular membrane. With the increase of frequency, there were local necrosis and infiltration of inflammatory cells. But no steatosis was seen. Tempol early treatment and IA groups exhibited no hepatocellular swelling or inflammatory cell infiltration. The activities of ALT and AST increased along with the increased frequency in IH group (all P < 0.01). The levels of ALT and AST in IH group ((48.6 ± 3.6), (25.4 ± 2.6) U/L) were higher than those in IA group ((20.3 ± 3.1), (18.7 ± 1.3) U/L) and CG group ((17.5 ± 2.4), (18.8 ± 1.3) U/L) (all P < 0.01). It decreased in Tempol treatment group, and more obviously when early intervention was applied (all P < 0.01). Liver homogenate TG, TC and FFA had no difference among IH, IA and CG groups (all P > 0.05), and no difference in different frequencies in IH group (all P > 0.05). The levels of serum TG, TC in IH groups were higher than those in IA and CG groups while ADP was lower (all P < 0.01). It changed more obviously in different frequencies in IH group (all P < 0.01). In Tempol treatment group, serum TG, TC decreased while ADP increased and changed more obviously when early intervention was applied (all P < 0.01). CONCLUSIONS: CIH causes the morphologic changes of liver and the elevations of ALT and AST, but results not in lipid deposition in liver cells. Anti-oxidation of Tempol can block intermittent hypoxia associated with liver injury.

[The effects of chronic intermittent hypoxia on blood pressure and sympathetic nerve activity in rats].

OBJECTIVE: To observe the changes of blood pressure and sympathetic nerve activity under different degrees of chronic intermittent hypoxia (CIH) in rats, and therefore to explore the effects of CIH on blood pressure and sympathetic nerve activity and the correlation between blood pressure and sympathetic nerve activity in the pathogenesis of CIH-induced hypertension. METHODS: Male Wistar rats (n = 168) were randomly divided into untreated group (UD), severe intermittent hypoxia group (IH(1)), moderate intermittent hypoxia group (IH(2)), mild intermittent hypoxia group (IH(3)), continuous hypoxia group (CH), sham control group (SC) and were exposed to different conditions. Rats (n = 8) of the UD group were sacrificed before the experiment, while rats of the other groups were killed in weeks 2, 4, 6, and 8 of the experiment. Anticoagulated venous blood was obtained and plasma was stored at -80°C. Systolic arterial pressure (SBP) was recorded before and after the experiment, while plasma norepinephrine (NE) was measured after the experiment. RESULTS: Before the experiment, the SBP of rats showed no significant differences among groups (F = 0.008, P > 0.05), but the SBP of rats in the intermittent hypoxia groups increased gradually, and higher than the UD group, the SC group and the CH group from the beginning of week 4 (P < 0.05 or P < 0.01). The blood pressure was positively related with the degree of hypoxia (F = 9.844, P < 0.01), and that of the IH(1) group was significantly higher than that of the IH(3) group (P < 0.05), while no significant changes were found in the SC and the CH groups. The plasma NE level of rats in the intermittent hypoxia groups increased gradually with the experiment and significantly higher than that of the UD group, the SC group and the CH group at week 8 (P < 0.05 or P < 0.01), and the level of NE was positively related with the degree of hypoxia (F = 11.537, P < 0.01). The NE level of the IH(1) group was significantly higher than that of the IH(3) group (P < 0.05), but no significant change was found in the SC and the CH groups. The plasma NE levels were positively related with blood pressure (r = 0.530, P < 0.01). CONCLUSIONS: CIH can cause increased blood pressure and sympathetic activity in rats, and the effect was dependent on the degree of hypoxia and the time of exposure. The results suggested that CIH-induced higher blood pressure was associated with increased sympathetic activity.

Effects of various degrees of oxidative stress induced by intermittent hypoxia in rat myocardial tissues.

BACKGROUND AND OBJECTIVE: The aim of this study was to investigate the mechanism by which oxidative stress induced by chronic intermittent hypoxia (IH) causes myocardial damage in obstructive sleep apnoea syndrome. METHODS: A total of 160 Wistar rats were divided into five experimental groups and subjected to chronic IH with different concentrations of oxygen (5%, 7.5%, 10% IH groups; 10% continuous oxygen and normoxia control groups). Eight rats from each group were sacrificed at the 2-, 4-, 6- and 8-week time points. Superoxide dismutase (SOD) activity, malondialdehyde (MDA) levels and total anti-oxidant capability (T-AOC) were measured in supernatants of heart homogenates. Expression of the nicotinamide adenine dinucleotide phosphate (NADPH) oxidase subunits, p22(phox) and NOX2, and thioredoxin-2 (Trx-2) genes were determined by measuring messenger RNA (mRNA) levels by real-time polymerase chain reaction. RESULTS: Compared with the control groups, MDA levels increased over time in the IH groups, whereas T-AOC and SOD activity decreased over time. MDA, T-AOC and SOD activity peaked at 6 weeks into the IH treatment. The 5% IH group showed significantly higher expression of p22(phox) and thioredoxin-2 mRNA, as compared with the other IH groups, as well as the control groups. CONCLUSIONS: The severity of oxidative stress induced by chronic IH in myocardial tissue was significantly correlated with the degree of IH. NADPH oxidase and Trx-2 are important mediators of oxidative stress induced by IH.

Time-dependent inflammatory factor production and NFκB activation in a rodent model of intermittent hypoxia.

OBJECTIVE: To study the systemic production of inflammatory factors and activation of transcription factor nuclear factor kappa B (NF-κB) in response to different levels of intermittent hypoxia and time. METHODS: A total of 160 male Wistar rats were divided randomly into five groups. The first three groups were exposed to 5%, 7.5% and 10% intermittent hypoxia (referred to as IH-1, IH-2, and IH-3 respectively), the fourth group were subjected to 10% sustained hypoxia (abbreviated as SH), and the control group were exposed to normal oxygen (designated SC). At the second, fourth, sixth, and eighth week, eight rats in each group were sacrificed to collect serum. Enzyme-linked immunosorbent assay (ELISA) was used to detect the serum concentration of tumour necrosis factor alpha (TNF-α), interleukin-8 (IL-8), interleukin-6 (IL-6) and interleukin-10 (IL-10). Western blot was used to detect the protein levels of the phosphorylated NF-κB P65 in the nucleus of arterial endothelial cells. RESULTS: In all three IH groups serum levels of TNF-α, IL-8 and IL-6 showed consecutive increment from onset to the 6th week under intermittent hypoxia; the levels of TNF-α and IL-8 dropped slightly on the 8th week, whereas those of IL-6 continued to increase. The levels of IL-10 decreased and reached nadir at the 6th week of intermittent hypoxia treatment. The inflammatory response was the most pronounced in the 6th week, at which time the TNF-α, IL-8 and IL-6 levels in IH groups were significantly higher than in the SC and SH group (F = 30.04, 11.77, 18.589; p <0.05). IL-10 levels were significantly lower than the SC and SH group (F = 10.403, p <0.05). Levels of TNF-α and IL-8 in the IH-1 group were significantly higher than those in the IH-3 group (F = 1.20, 34.68; p = 0.049, 0.046). Protein levels of phosphorylated NF-κB P65 in endothelial cells collected from thoracic aorta in all three IH groups were significantly higher than those in SC and SH groups (F = 63.136, p = 0.01). A close correlation was identified between NF-κB p65 phosphorylation and the levels of TNF-α, IL-8, IL-6 and IL-10 (p = 0.01). CONCLUSIONS: The inflammatory response, manifested by serum levels of inflammatory factors and nuclear accumulation of activated NF-κB P65, was more serious in the IH group than in the SH and control group, and was dependent on hypoxia levels. This reaction increased initially and then decreased, which indicates the presence of compensatory mechanisms and an adaptive response to such stressors in the body. Notably, the correlation of NFκB activation to production of inflammatory factors under intermittent hypoxia implies an important role of this transcription factor in inflammation-induced cardiovascular damage occurring during obstructive sleep apnoea (OSA), which has a typical breathing pattern of intermittent hypoxia.