Assessing Airway Resistance Using Plethysmography as Lung Function Testing Among Asymptomatic Rheumatoid Arthritis Patients.

Pulmonary events in rheumatoid arthritis (RA) reflects the involvement of pleurae, lung interstitium, and airways. Overall, pulmonary manifestations are estimated to cause 10–20% of mortalities in RA. Respiratory system involvement as extra-articular presentations of RA is common among some Saudi patients. This study aims to evaluate specific airway conductance (sGaw), airway resistance (Raw), and specific airway resistance (sRaw), using plethysmography. Comparison for deployed methods is made by forced spirometer as an indicator for obstruction among patients with RA. The study sought to use the methods to enhance lung testing among RA patients. An analytical, hospital-based study was carried out at pulmonary function test laboratory, department of respiratory care King Saud Medical City (KSMC). RA patients were selected, with an age group of 18-75years. The tests for Forced spirometer and plethysmography were carried out to assess and analyze how the respiratory mechanism was impacted by the disease. Data collected was analyzed using Statistical Package for Social Sciences (SPSS), version 21. The obstructive and mixed ventilation patterns constituted 15%; the mean values of Raw and sRaw were significantly higher compared to mean values predicted for participants selected during the study, while sGaw was significantly lower compared to mean values predicted for participants selected. Monitoring of airway resistance parameters using plethysmography can be used as indicators of lung function testing among RA patients.

Positive Expiratory Pressure: A Potential Therapy to Mitigate Acute Bronchoconstriction in the Asthma of Obesity

Late-onset non-allergic (LONA) asthma in obesity is characterized by increased peripheral airway closure secondary to abnormally collapsible airways. We hypothesized that positive expiratory pressure (PEP) would mitigate the tendency to airway closure during bronchoconstriction, potentially serving as rescue therapy for LONA asthma of obesity. The PC20 dose of methacholine was determined in 18 obese participants with LONA asthma. At each of 4 subsequent visits, we used oscillometry to measure input respiratory impedance (Zrs) over 8 minutes; participants received their PC20 concentration of methacholine aerosol during the first 4.5 minutes. PEP combinations of either 0 or 10 cmH2O either during and/or after the methacholine delivery were applied, randomized between visits. Parameters characterizing respiratory system mechanics were extracted from the Zrs spectra. In 18 LONA asthma patients (14 females, BMI: 39.6±3.4 kg/m2), 10 cmH2O PEP during methacholine reduced elevations in the central airway resistance, peripheral airway resistance and elastance, and breathing frequency was also reduced. During the 3.5 min following methacholine delivery, PEP of 10 cmH2O reduced Ax and peripheral elastance compared to no PEP. PEP mitigates the onset of airway narrowing brought on by methacholine challenge, and airway closure once it is established. PEP thus might serve as a non-pharmacologic therapy to manage acute airway narrowing for obese LONA asthma.

Changes in Expressions of HSP27, HSP70 and Soluble Glycoprotein in Heart Failure Rats Complicated with Pulmonary Edema and Correlations with Cardiopulmonary Functions Running title: Expressions of HSP27, HSP70 and Soluble Glycoprotein in Heart Failure

Objective: The study aimed to investigate the changes in expressions of heat shock protein 27 (HSP27), HSP70 and soluble glycoprotein (SGP) in heart failure (HF) rats complicated with pulmonary edema, and explore their potential correlations with cardiopulmonary functions. Methods: The rat model of HF was established, and the rats were divided into HF model group (model group, n=15) and normal group (n=15). After successful modeling, MRI and ECG were applied to detect the cardiac function indexes of the rats. The myocardial function indexes were determined, the injury of myocardial tissues was observed via hematoxylin and eosin (HE) staining, and the content of myeloperoxidase (MPO), matrix metalloproteinase-9 (MMP-9) and tumor necrosis factor-alpha (TNF-a) in the blood was measured. The partial pressure of oxygen (Pa02) and oxygenation index (01) were observed, and the airway resistance and lung compliance were examined. Moreover, quantitative polymerase chain reaction (qPCR) and Western blotting assay were performed to detect the gene and protein expression levels of HSP27, HSP70 and SGP130. Results: The levels of serum creatine kinase (CK), creatine (Cr) and blood urea nitrogen (BUN) were increased markedly in model group (p<0.05). Model group had notably decreased fractional shortening (FS) and ejection fraction (EF) compared with normal group (p<0.05), while the opposite results of left ventricular end-diastolic diameter (LVEDD) and left ventricular end-systolic diameter (LVESD) were detected. In model group, the content of serum MPO, MMP-9 and TNF-a was raised remarkably (p<0.05), 01 and Pa02were reduced notably (p<0.05), the airway resistance was increased (p<0.05), and the lung compliance was decreased (p<0.05). Obviously elevated gene and protein expression levels of HSP27, HSP70 and SGP130 were detected in model group (p<0.05). Conclusion: The expressions of HSP27, HSP70 and SGP130 are increased in HF rats complicated with pulmonary edema, seriously affecting the cardiopulmonary functions of the rats.

Dexmedetomidine Reduces IL-4 and IgE Expression Through Downregulation of TLR4/NF-κ Signaling Pathway to Alleviate Airway hyperresponsiveness in OVA Mice

Background: Asthma is a disease that affects health worldwide. It is characterised by inflammation and airway hyperreactivity. Because airway hyperreactivity can occur in other diseases, perioperative airway hyperreactivity is more insidious and widespread than in asthma and has serious implications that need to be addressed urgently. The use of dexmedetomidine in acute asthma and lung protection has been reported, but the exact mechanism is unclear. Objective: To investigate the effectiveness and mechanisms associated with dexmedetomidine in airway hyperresponsiveness.Methods: Forty BALB/c female mice were randomly divided into five groups: group K (blank group), group A (asthma group), group HD (asthma + dexmedetomidine treatment group), group TH (asthma + yohimbine group) and group HT (asthma + dexmedetomidine + yohimbine group), and the airway resistance of group K, group A and group HD were analysed by invasive airway resistance assay, ELISA assay, immunohistochemistry and q-PCR, respectively. Airway resistance; IL-4 and IgE levels in serum and BLAF; and IL-4, IL-13, Muc5AC, NFκB, TLR2, TLR4 and TSLP1 protein levels in lung tissues of the 5 groups were analysed by invasive airway resistance assay, ELISA, immunohistochemistry and qPCR. RESULTS: Compared with group A, there were statistical differences in airway resistance (P < 0.05); LIL-4 and IgE (P < 0.05) in serum and BLAF; and Muc5AC, TLR4 and NFκB protein contents (P < 0.05) in lung tissues in the HD group. Conclusion: 1. Dexmedetomidine can attenuate airway hyperresponsiveness in the OVA asthma model; 2. Dexmedetomidine reduced the production of IL-4 and IgE by down-regulating the TLR4/NF-κB signaling pathway, thereby reducing the lung inflammatory response and airway hyperresponsiveness in the OVA-induced asthma model.