Total oxidant and antioxidant status and paraoxonase 1 levels of children with noncystic fibrosis bronchiectasis

The effect of N-acetylcysteine in patients with non-cystic fibrosis bronchiectasis (NINCFB): study protocol for a multicentre, double-blind, randomised, placebo-controlled trial

Background

N-acetylcysteine (NAC), which is specifically involved in airway mucus clearance and antioxidation, is recommended by the treatment guideline for non-cystic fibrosis bronchiectasis (NCFB). However, there is little clinical evidence of its long-term efficacy concerning quality of life (QoL) and exacerbation in patients with NCFB. In addition, the influences of NAC on airway bacterial colonization, chronic inflammation and oxidative stress in NCFB are also unclear.

Methods

NINCFB is a prospective, multicentre, double-blind, randomised, placebo-controlled trial that will recruit 119 patients with NCFB and randomly divide them into an NAC group (n = 79) and a control group (n = 40). Participants in the NAC group will receive 600 mg oral NAC twice daily for 52 weeks, while patients in the control group will receive 600 mg placebo twice daily for 52 weeks. The information at baseline will be collected once participants are enrolled. The primary endpoints are the changes in St George’s Respiratory Questionnaire scores and the number of exacerbations in 52 weeks. The secondary endpoints are the 16S rRNA of sputum and the levels of inflammatory factors and oxidative stressors in sputum and serum. Other data related to radiography, lung function tests, number of oral and/or intravenous antibiotic therapies and adverse events (AEs) will also be analysed. Further subgroup analysis distinguished by the severity of disease, severity of lung function, airway bacterial colonization and exacerbation frequency will be performed.

Discussion

The objective of this study is to determine the long-term efficacy of NAC on QoL and exacerbation of NCFB and to explore the effectiveness of NAC for antibiosis, anti-inflammation and antioxidation in NCFB. The study results will provide high-quality clinical proof for the revision and optimization of treatment guidelines and for expert consensus on NCFB treatment.

Trial registration

The trial was registered on the Chinese Clinical Trial Register at April 11, 2020 (chictr.org.cn, ChiCTR2000031817).

Evaluation of Thiol/Disulfide Homeostasis in Bronchiectasis

Purpose

Thiols are sulfhydryl-containing organic compounds that have an important role in preventing cellular oxidative stress. This study compares the blood oxidative stress marker levels in bronchiectasis cases during their stable periods with healthy controls.

Materials and Methods

Seventy-seven patients (49 patients with stable bronchiectasis/28 healthy controls), followed up by the chest disease clinic, were included in the study. Peripheral blood thiol-disulfide parameters (NT: native thiol (−SH); TT: total thiol (−SH + SS); SS: disulfide (−SS); SS-SH: disulfide/native thiol index; SS-TT: disulphide/total thiol index; SH-TT: native thiol/total thiol index), and ischemia-modified albumin (IMA) levels were examined in the stable bronchiectasis group and the control group. Thiol-disulfide homeostasis was evaluated using a novel and automated assay. Findings and Result. Blood native thiol levels in patients with stable bronchiectasis were found to be significantly higher compared with healthy controls. A positive correlation between the total airway disease score and IMA levels was present. Our findings revealed that native thiol levels, which constitute a part of the antioxidant defense system, are increased in patients with stable bronchiectasis.

Plasticizer and catalyst co-functionalized PEDOT:PSS enables stretchable electrochemical sensing of living cells

Recently, stretchable electrochemical sensors have stood out as a powerful tool for the detection of soft cells and tissues, since they could perfectly comply with the deformation of living organisms and synchronously monitor mechanically evoked biomolecule release. However, existing strategies for the fabrication of stretchable electrochemical sensors still face with huge challenges due to scarce electrode materials, demanding processing techniques and great complexity in further functionalization. Herein, we report a novel and facile strategy for one-step preparation of stretchable electrochemical biosensors by doping ionic liquid and catalyst into a conductive polymer (poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate), PEDOT:PSS). Bis(trifluoromethane) sulfonimide lithium salt as a small-molecule plasticizer can significantly improve the stretchability and conductivity of the PEDOT:PSS film, and cobalt phthalocyanine as an electrocatalyst endows the film with excellent electrochemical sensing performance. Moreover, the functionalized PEDOT:PSS retained good cell biocompatibility with two extra dopants. These satisfactory properties allowed the real-time monitoring of stretch-induced transient hydrogen peroxide release from cells. This work presents a versatile strategy to fabricate conductive polymer-based stretchable electrodes with easy processing and excellent performance, which benefits the in-depth exploration of sophisticated life activities by electrochemical sensing.