The roles of bacteria and viruses in COPD-Bronchiectasis association: A prospective cohort study.

BACKGROUND: Exacerbations are implicated in bronchiectasis and COPD, which frequently co-exist [COPD-Bronchiectasis association (CBA)]. We aimed to determine the bacterial and viral spectrum at stable-state and exacerbation onset of CBA, and their association between pathogen detection and with exacerbations of CBA as compared with bronchiectasis. METHODS: We prospectively collected spontaneous sputum from adults with CBA, bronchiectasis with (BO) and without airflow obstruction (BNO) for bacterial culture and viral detection at stable-state and exacerbations. RESULTS: We enrolled 76 patients with CBA, 58 with BO, and 138 with BNO (711 stable and 207 exacerbation visits). Bacterial detection rate increased from BNO, CBA to BO at steady-state (P=0.02), but not at AE onset (P=0.91). No significant differences in viral detection rate were found among BNO, CBA and BO. Compared with steady-state, viral isolations occurred more frequently at exacerbation in BNO (15.8% vs 32.1%, P=0.001) and CBA (19.5% vs 30.6%, P=0.036) only. In CBA, isolation of viruses, human metapneumovirus and bacteria plus viruses was associated with exacerbation. Repeated detection of Pseudomonas aeruginosa correlated with higher modified Reiff score (P=0.032) in CBA but not in BO (P=0.178). Repeated detection of Pseudomonas aeruginosa yielded a shorter time to the first exacerbation in CBA [median: 4.3 vs 11.1 months, P=0.006] but not in BO (median: 8.4 vs 7.6 months, P=0.47). CONCLUSIONS: Patients with CBA have greater disease severity than those with BNO. While isolation of viruses is associated with CBA exacerbations, repeated detection of Pseudomonas aeruginosa confers greater impact of future exacerbations on CBA than on BO.

Bacteria and viruses and clinical outcomes of asthma-bronchiectasis overlap syndrome: A cohort study.

BACKGROUND: Despite the high prevalence of co-existing bronchiectasis and asthma (asthma-bronchiectasis overlap syndrome [ABOS]), little is known regarding the dominant pathogens and clinical correlates. OBJECTIVE: To investigate the bacteria and viruses which differentially dominate in ABOS (including its subtypes) compared with bronchiectasis alone, and determine their relevance with bronchiectasis severity and exacerbations. METHODS: This was a prospective observational cohort study conducted between March 2017 and August 2023. We included 81 patients with ABOS and 107 patients with bronchiectasis alone. At steady-state baseline, patients underwent comprehensive assessments and sputum collection for bacterial culture and viral detection (quantitative polymerase-chain-reaction). Patients were followed-up to record exacerbation and spirometry. RESULTS: Patients with ABOS had significantly higher symptom burden and exacerbation frequency than those with bronchiectasis alone. Despite similar pathogen spectrum, the rate of bacteria-virus co-detection increased less substantially at acute exacerbations (AE) onset than at steady-state compared with bronchiectasis alone. Pathogenic bacteria (particularly Pseudomonas aeruginosa) were detected fairly common (exceeding 50%) in ABOS and were associated with greater severity of bronchiectasis when stable and conferred greater exacerbation risks at follow-up. Viral but not bacterial compositions changed substantially at AE onset compared with clinical stability. Higher blood eosinophil count, moderate-to-severe bronchiectasis and non-atopy were associated with higher odds of bacterial, but not viral, detection (all p < 0.05). CONCLUSION: Detection of bacteria or virus is associated with bronchiectasis severity or clinical outcomes in ABOS. This highlights the importance of integrating sputum microbial assessment for ascertaining the dominant pathophysiology (atopy vs. infection) and longitudinal trajectory prediction in ABOS.

Advances in pharmacotherapy for bronchiectasis in adults.

INTRODUCTION: Bronchiectasis has become a growing concern of chronic airway disease because of the enormous socioeconomic burden. Four cardinal interdependent components - impaired airway defense, recurrent airway infections, inflammatory response, and airway damage, in conjunction with the underlying etiology, have collectively played a role in modulating the vicious vortex of the pathogenesis and progression of bronchiectasis. Current pharmacotherapy aims to target at these aspects to break the vicious vortex. AREAS COVERED: The authors retrieve and review, in MEDLINE, Web of Science and ClinicalTrials.gov registry, the studies about pharmacotherapy for bronchiectasis from these aspects: antibiotics, mucoactive medications, bronchodilators, anti-inflammatory drug, and etiological treatment. EXPERT OPINION: Future drug development and clinical trials of bronchiectasis need to pay more attention to the different phenotypes or endotypes of bronchiectasis. There is a need for the development of novel inhaled antibiotics that could reduce bacterial loads, improve quality-of-life, and decrease exacerbation risks. More efforts are needed to explore the next-generation neutrophil-targeted therapeutic drugs that are expected to ameliorate respiratory symptom burden, reduce exacerbation risks, and hinder airway destruction in bronchiectasis.

Sputum pathogen spectrum and clinical outcomes of upper respiratory tract infection in bronchiectasis exacerbation: a prospective cohort study.

Upper respiratory tract infection (URTI) is common in humans. We sought to profile sputum pathogen spectrum and impact of URTI on acute exacerbation of bronchiectasis (AE). Between March 2017 and December 2021, we prospectively collected sputum from adults with bronchiectasis. We stratified AEs into events related (URTI-AE) and unrelated to URTI (non-URTI-AE). We captured URTI without onset of AE (URTI-non-AE). We did bacterial culture and viral detection with polymerase chain reaction, and explored the pathogen spectrum and clinical impacts of URTI-AE via longitudinal follow-up. Finally, we collected 479 non-AE samples (113 collected at URTI-non-AE and 225 collected at clinically stable) and 170 AE samples (89 collected at URTI-AE and 81 collect at non-URTI-AE). The viral detection rate was significantly higher in URTI-AE (46.1%) than in non-URTI-AE (4.9%) and URTI-non-AE (11.5%) (both P < 0.01). Rhinovirus [odds ratio (OR): 5.00, 95% confidence interval (95%CI): 1.06-23.56, P = 0.03] detection was independently associated with URTI-AE compared with non-URTI-AE. URTI-AE tended to yield higher viral load and detection rate of rhinovirus, metapneumovirus and bacterial shifting compared with URTI-non-AE. URTI-AE was associated with higher initial viral loads (esp. rhinovirus, metapneumovirus), greater symptom burden (higher scores of three validated questionnaires) and prolonged recovery compared to those without. Having experienced URTI-AE predicted a greater risk of future URTI-AE (OR: 10.90, 95%CI: 3.60-33.05). In summary, URTI is associated with a distinct pathogen spectrum and aggravates bronchiectasis exacerbation, providing the scientific rationale for the prevention of URTI to hinder bronchiectasis progression.

Motile Ciliary Disorders of the Nasal Epithelium in Adults With Bronchiectasis.

BACKGROUND: Motile ciliary disorder (MCD) has been implicated in chronic inflammatory airway diseases such as asthma and COPD. RESEARCH QUESTION: What are the characteristics of MCD of the nasal epithelium and its association with disease severity and inflammatory endotypes in adults with bronchiectasis? STUDY DESIGN AND METHODS: In this observational study, we recruited 167 patients with bronchiectasis and 39 healthy control participants who underwent brushing of the nasal epithelium. A subgroup of patients underwent bronchoscopy for bronchial epithelium sampling (n = 13), elective surgery for bronchial epithelium biopsy (n = 18), and blood sampling for next-generation sequencing (n = 37). We characterized systemic and airway inflammatory endotypes in bronchiectasis. We conducted immunofluorescence assays to profile ultrastructural (dynein axonemal heavy chain 5 [DNAH5], dynein intermediate chain 1 [DNAI1], radial spoke head protein 9 [RSPH9]) and ciliogenesis marker expression (Ezrin). RESULTS: MCD was present in 89.8% of patients with bronchiectasis, 67.6% showed secondary MCD, and 16.2% showed primary plus secondary MCD. Compared with healthy control participants, patients with bronchiectasis yielded abnormal staining patterns of DNAH5, DNAI1, and RSPH9 (but not Ezrin) that were more prominent in moderate to severe bronchiectasis. MCD pattern scores largely were consistent between upper and lower airways and between large-to-medium and small airways in bronchiectasis. Coexisting nasal diseases and asthma did not confound nasal ciliary ultrastructural marker expression significantly. The propensity of MCD was unaffected by the airway or systemic inflammatory endotypes. MCD, particularly an ultrastructural abnormality, was notable in patients with mild bronchiectasis who showed blood or sputum eosinophilia. INTERPRETATION: Nasal ciliary markers profiling provides complimentary information to clinical endotyping of bronchiectasis.

Phenotyping acute exacerbation of COPD: what more can we do for hospitalised patients?

Hospitalised #AECOPD are characterised by multiple facets of aetiology. The clinical interpretation of the composite phenotypes of AECOPD and the robustness of the AECOPD phenotype need to be discussed further. https://bit.ly/3grzQEO.

TGF-ß1 Provides Neuroprotection via Inhibition of Microglial Activation in 3-Acetylpyridine-Induced Cerebellar Ataxia Model Rats.

Cerebellar ataxias (CAs) consist of a heterogeneous group of neurodegenerative diseases hallmarked by motor deficits and deterioration of the cerebellum and its associated circuitries. Neuroinflammatory responses are present in CA brain, but how neuroinflammation may contribute to CA pathogenesis remain unresolved. Here, we investigate whether transforming growth factor (TGF)-ß1, which possesses anti-inflammatory and neuroprotective properties, can ameliorate the microglia-mediated neuroinflammation and thereby alleviate neurodegeneration in CA. In the current study, we administered TGF-ß1 via the intracerebroventricle (ICV) in CA model rats, by intraperitoneal injection of 3-acetylpyridine (3-AP), to reveal the neuroprotective role of TGF-ß1. The TGF-ß1 administration after 3-AP injection ameliorated motor impairments and reduced the calbindin-positive neuron loss and apoptosis in the brain stem and cerebellum. Meanwhile, 3-AP induced microglial activation and inflammatory responses in vivo, which were determined by morphological alteration and an increase in expression of CD11b, enhancement of percentage of CD40 + and CD86 + microglial cells, upregulation of pro-inflammatory mediators, tumor necrosis factor (TNF)-α and interleukin (IL)-1ß, and a downregulation of neurotrophic factor, insulin-like growth factor (IGF)-1 in the brain stem and cerebellum. TGF-ß1 treatment significantly prevented all the changes caused by 3-AP. In addition, in vitro experiments, TGF-ß1 directly attenuated 3-AP-induced microglial activation and inflammatory responses in primary cultures. Purkinje cell exposure to supernatants of primary microglia that had been treated with TGF-ß1 reduced neuronal loss and apoptosis induced by 3-AP-treated microglial supernatants. Furthermore, the protective effect was similar to those treated with TNF-α-neutralizing antibody. These findings suggest that TGF-ß1 protects against neurodegeneration in 3-AP-induced CA rats via inhibiting microglial activation and at least partly TNF-α release.

The Role of Follow-up Evaluation in the Diagnostic Algorithm of Idiopathic Interstitial Pneumonia: A Retrospective Study.

We aimed to evaluate the alteration of diagnosis of individual expert and multidisciplinary discussion (MDD) team in the longitudinal diagnostic assessment of idiopathic interstitial pneumonia (IIP). The retrospective analysis included 56 patients diagnosed as IIP by The First Affiliated Hospital of Guangzhou Medical University with follow-up visits during Jan 1st to Aug 31st 2014. Each expert was provided information in a sequential manner and was asked to assign an individual diagnosis and an MDD diagnosis after group discussion. The level of agreement among individual experts and between different visits was calculated by kappa and the agreement between individual specialist and MDD team with different consensus levels was measured by weighted-kappa coefficients. Follow-up data changed the original clinical diagnosis and MDD diagnosis in 24.1% and 10.7% of all cases, respectively, and clinician and MDD consensus level in 55.4% and 25.0%, respectively. The diagnostic performance of individual clinicians or radiologist was closer to that of the MDD compared with the pathologist, and follow-up further increased the agreement. The longitudinal evaluation of patients with IIP improved the inter-observer agreement in a multidisciplinary team. The performance of individual clinicians or radiologist was approaching the accuracy of multidisciplinary team when provided with follow-up data.

[Preparation and Phosphorus Removal Mechanism of Highly Efficient Phosphorus Adsorbent Mg/Al-LDO].

Aiming at the problem of phosphorus removal in water, Mg/Al-layered double hydroxides (Mg/Al-LDHs) were synthesized via optimized constant pH co-precipitation method, and highly efficient phosphorus adsorbent Mg/Al-layered double oxide(Mg/Al-LDO) was obtained when it was calcined at high temperature. Based on the adsorption characteristics of phosphorus removal, the study combined Zeta potential, X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) to analyze the changes of isoelectric point, crystal structure and functional group before and after adsorption. In addition, Mg/Al-LDO of phosphorus adsorption mechanism was discussed. The results indicated that using the optimized co-precipitation method in the conditions of Mg/Al=2:1, calcination temperature 450℃, and calcination time 2 h, the Mg/Al-LDO adsorption capacity of phosphate was the best, and the maximum adsorption capacity could reach 176.94 mg·g-1, which was basically consistent with the theoretical adsorption capacity of 191.57 mg·g-1, far higher than those of Mg/Al-LDHs and other phosphorus adsorbents. The results showed that the experimental data has the best fitting result with pseudo-second-order kinetics model. The adsorption process was consistent with Langmuir adsorption isotherm model. The results of Zeta potential, XRD and FTIR showed that phosphorus adsorption of Mg/Al-LDO was accomplished co-operatively by electrostatic attraction, anion in layer, ions exchange, and surface co-ordination.

Diagnostic yield and postoperative mortality associated with surgical lung biopsy for evaluation of interstitial lung diseases: A systematic review and meta-analysis.

OBJECTIVES: Surgical lung biopsy plays an important role in providing pathologic results, thus complementing the diagnostic rationale for suspected interstitial lung diseases. We performed a systematic review and meta-analysis regarding the diagnostic yield and postoperative mortality rate of surgical lung biopsy in patients with suspected interstitial lung diseases because of the wide variation in previously reported effectiveness and safety concerns. METHODS: We systematically searched for published studies between 2000 and 2014 evaluating surgical lung biopsy in the diagnosis of interstitial lung diseases. Subgroup analysis was performed to identify the possible source of study heterogeneity. RESULTS: Twenty-three studies contributed 2148 patients for the analysis. The median diagnostic yield was 95% (range, 42%-100%), with idiopathic pulmonary fibrosis as the most frequent diagnosis (618, 33.5%). Surgical lung biopsy was mainly guided by high-resolution computed tomography manifestations. Biopsy site, biopsy number, and the surgical lung biopsy method may not be associated with the diagnostic accuracy. The pooled postoperative mortality rate for included studies was 3.6% (95% confidence interval, 2.1-5.5), with significant heterogeneity observed. Subgroup analysis revealed that exclusion criteria based on immunocompromised status, mechanical ventilation, and severe respiratory dysfunction (diffusing capacity of lung for carbon monoxide <35% or forced vital capacity <55% predicted), but not surgical lung biopsy technique or underlying interstitial lung disease subtype, may be possible sources of heterogeneity. CONCLUSIONS: We demonstrated a satisfactory diagnostic performance with a favorable safety profile of surgical lung biopsy in the diagnosis of suspected interstitial lung diseases. Surgical lung biopsy is especially recommended in patients with clinical information indicative but atypical of idiopathic pulmonary fibrosis, whereas the benefit of surgical lung biopsy should be carefully balanced against the risk for patients with immunocompromised status, mechanical ventilation dependence, or severe respiratory dysfunction.

Molecular determinants of Kv1.5 channel block by diphenyl phosphine oxide-1.

Kv1.5 channels conduct the ultra-rapid delayed rectifier current (I(Kur)) that contributes to action potential repolarization of human atrial myocytes. Block of these channels has been proposed as a treatment for atrial arrhythmias. Diphenyl phosphine oxide-1 (DPO-1) is a novel and potent inhibitor of Kv1.5 potassium channels. The present study was undertaken to characterize the mechanisms and molecular determinants of channel block by DPO-1. Experiments were carried out on wild-type and mutant Kv1.5 channels expressed in Xenopus laevis oocytes using the standard two microelectrode voltage clamp technique. DPO-1 blocked Kv1.5 current in oocytes with an IC(50) of 0.78+/-0.12 microM at +40 mV. Block was enhanced by higher rates of stimulation, consistent with preferential binding of the drug to the open state of the channel. Ala-scanning mutagenesis of the pore domain of Kv1.5 identified the residues Thr480, Leu499, Leu506, Ile508, Leu510 and Val514 as components of the putative binding site for DPO-1, partially overlapping the site previously defined for the Kv1.5 channel blockers AVE0118 and S0100176. Block of Kv1.5 by DPO-1 was significantly reduced in the presence of Kvbeta1.3.