A review of novel research technology to explore the mystery of traditional Chinese medicine: Terahertz.

During the 2022 Annual National Terahertz Biophysics Conference, the hypothesis was proposed that bio frequency electromagnetic fields sensitive points, akin to acupuncture points, exist in the human body. This development has prompted numerous researchers to apply terahertz technology to the field of traditional Chinese medicine (TCM). In recent years, terahertz technology has achieved notable progress in the field of TCM, particularly concerning the meridian-collateral system. This review systematically presents the advancements in terahertz technology and its implications on TCM theory from a biophysical perspective. Additionally, it summarizes the utilization of terahertz waves in elucidating aspects of TCM, particularly focusing on the scientific connotation of Qi, the theoretical foundation of the meridian-collateral system, and moxibustion in diagnosing and treating diseases. We aimed to explore the innovative applications and distinct advantages of terahertz technology in TCM and its feasibility as a pioneering technological tool for the modernization of TCM.

Advantages of a Novel Model for Predicting Hepatic Fibrosis in Chronic Hepatitis B Virus Carriers Compared with APRI and FIB-4 Scores.

Background and Aims: Aspartate aminotransferase-to-platelet ratio index (APRI) and fibrosis-4 index (FIB-4) are widely used to assess liver fibrosis in chronic hepatitis B virus (HBV) infection. Currently, the definition of normal alanine aminotransferase (ALT) is controversial. We aimed to examine the diagnostic value of APRI and FIB-4 in chronic HBV carriers with different upper limits of normal (ULNs) for ALT. Methods: 581 chronic HBV carriers were divided into the following four groups based on different ULNs for ALT: chronic HBV carriers I, II, III, and IV. Furthermore, 106 chronic HBV carriers formed an external validation group. Predictive values of APRI and FIB-4 were elucidated using the area under the curve (AUC). A liver fibrosis-predictive model-GPSA (named for its measure of gamma glutamyl transpeptidase, platelet count, HBsAg and albumin) was developed using multivariate logistic regression analysis. Results: In chronic HBV carriers I, the AUCs of APRI and FIB-4 were 0.680 and 0.609 for significant fibrosis and 0.678 and 0.661 for cirrhosis, respectively. The AUCs of GPSA for significant fibrosis in the training group, internal group, and external validation group were 0.877, 0.837, and 0.871, respectively. The diagnostic value of GPSA differed among chronic HBV carriers I, II, III, and IV, with AUCs for significant fibrosis being 0.857, 0.853, 0.868, and 0.905 and AUCs for cirrhosis being 0.901, 0.905, 0.886, and 0.913, respectively. GPSA showed a higher diagnostic value than APRI and FIB-4 for predicting significant fibrosis in the four groups. Conclusions: The GPSA model allows for accurate diagnosis of liver fibrosis in chronic HBV carriers with different ULN for ALT.

[Field greenhouse gas emission characteristics and carbon footprint of ratoon rice]. / 再生稻田温室气体排放特征及碳足迹.

It is of great significance to understand the effects of different rice cultivation methods in southeast China on greenhouse gas emission characteristics and carbon footprint of paddy fields during rice cultivation for rice sustainable production. In this study, the popular conventional rice 'Jiafuzhan' and hybrid rice 'Yongyou 2640' were used as materials to establish four rice cultivation patterns suitable for different ecological types in Fujian Province: 1) double-cropping system, early rice and late rice with Jiafuzhan (D-J); 2) early maturing ratooning system, first season rice and ratooning season rice with Jiafuzhan (R-J); 3) middle-maturing ratooning system, first season rice and ratooning season with Yongyou 2640 (R-Y); and 4) single cropping system with Yongyou 2640 (S-Y), which should be synchronized in heading time with the counterpart (the ratooning season rice). Greenhouse gas emissions from paddy soil were measured by the closed static black box observation method and the gas chromatography method, respectively. The total direct and indirect greenhouse gas emissions (carbon footprints) from different rice farming patterns were evaluated by using the life cycle analysis. The results showed that greenhouse gas emissions in different rice cropping systems were lower in the early growth stage, then decreased after reaching the peak at the booting stage, demonstrating a double peak curve in the whole growth stage, in which the first peak was higher in early season or first season than the second peak in the late season or ratooning season in the cropping patterns. Moreover, the total greenhouse gas emissions were significantly different among cropping systems. The global warming potential (GWP) of different cropping patterns was in order of R-Y>D-J>S-Y>R-J, while the annual greenhouse gas emission intensity (GHGI) was D-J>S-Y>R-Y>R-J. GWP and GHGI of the ratooning system decreased by 26.1% and 14.1%, respectively, compared with those of the double-cropping system. The same pattern was observed in the ratooning rice of Yongyou 2640, which were decreased by 74.3% and 56.7%, respectively, compared with the counterpart, Yongyou 2640 in a single-cropping system synchronized heading. Carbon footprint of rice per unit yield ranged from 0.38-1.08 kg CO2-eq.·kg-1 under the different cropping systems, of which the carbon footprint of rice per unit yield was the highest under the double cropping system compared with that under other cropping systems. The reverse was true in the case of carbon footprint of rice per unit yield under the ratooning system with Yongyou 2640. Additionally, the main source of carbon footprint of different rice cropping patterns was CH4, contributing 44.2%-71.5%, suggesting that rice ratooning system could significantly reduce global warming potential and carbon emission intensity of rice in comparison with other cropping patterns. Therefore, it is key to select rice varieties with high yield and low carbon emission and to establish the supporting scientific cultivation techniques for effective reduction of CH4 emission and carbon footprint of paddy fields and promotion of ratooning rice production.

Effect of sequential high-flow nasal cannula oxygen therapy and non-invasive positive-pressure ventilation in patients with difficult weaning from mechanical ventilation after extubation on respiratory mechanics.

BACKGROUND: Patients with difficult weaning who undergo mechanical ventilation are more likely to be at risk of reintubation and the sequential use of oxygen therapy after extubation is a concern for clinicians. Therefore, the aim of the present study was to compare the effects of transnasal high-flow nasal cannula (HFNC) oxygen therapy and non-invasive positive-pressure ventilation (NIV) on respiratory mechanics in patients with difficult weaning. METHODS: The present study was a single-center, retrospective, observational study. Twenty-nine patients with difficult weaning off invasive mechanical ventilation from the Department of Critical Care Medicine, The First Affiliated Hospital of Guangzhou Medical University, from December 2018 to April 2021, were included. Within 48 h after extubation, alternate respiratory support with HFNC and NIV was provided. Relevant indicators were recorded after each support mode had been maintained for at least 60 min. These included esophageal pressure (Pes), gastric pressure (Pga), transdiaphragmatic pressure (Pdi), pressure-time product of Pes (PTPes), pressure-time product of Pga (PTPga), pressure-time product of Pdi (PTPdi), ratio of the PTPdi to the PTPes (PTPdi/PTPes), and ratio of the Pes to the Pdi (Pes/Pdi), diaphragmatic electromyogram (EMGdi), percentage of esophageal pressure coefficient of variation (CVes%),diaphragmatic electromyogram coefficient of variation (CVEMG),inspiratory time (Ti), expiratory time (Te) and respiratory cycle time (Ttot). RESULTS: Of the 29 patients included, 22 were males and 7 were females [age: 63.97±15.34 years, Acute Physiological and Chronic Health Estimation II (APACHE II) score: 18.00±5.63]. The CVes% and the Pes/Pdi were significantly higher in patients with NIV than HFNC using 40 L/min, CVes%: 9 (-6, 20) vs. -7 (-23, 6) and Pes/Pdi: 0.17 (-0.1, 0.53), vs. -0.12 (-0.43, 0.08) (P<0.05). The remaining indicators were not statistically different. CONCLUSIONS: The sequential NIV and HFNC can be tolerated in patients with such difficult weaning off mechanical ventilation after extubation, and more patients tend to choose HFNC subjectively. Compared with HFNC, NIV reduces the work of adjunctive respiratory muscle, but the patient's Pes dispersion is high when NIV is used, and it is necessary to pay attention to patient-ventilator coordination in clinical practice. We recommend alternating HFNC and NIV during the sequential respiratory therapy after extubation.

Assessment of respiratory drive with esophageal diaphragmatic electromyography in patients with acute respiratory distress syndrome treated with prone position ventilation.

BACKGROUND: Prone position ventilation (PPV) is an important strategy for patients with severe acute respiratory distress syndrome (ARDS). This prospective study investigated the use of electromyography of the diaphragm (EMGdi) for monitoring respiratory drive in patients with moderate to severe ARDS during long-term PPV. METHODS: An integrated nostril-gastric feeding tube containing an esophageal electrode and balloon was placed in 14 patients with severe ARDS prior to PPV. EMGdi and trans-pulmonary pressure (∆PL) data were collected before PPV (baseline), every 2 h during PPV, and 2 h after the restoration of supine position ventilation (post-2 h SPV). RESULTS: In ARDS patients, the static compliance of the chest wall was significantly decreased after PPV. EMGdi levels were slightly lower in the early, middle, and late stages of PPV compared with baseline. Patients who received neuromuscular blocker experienced a greater drop in EMGdi from baseline than those who did not. CONCLUSIONS: For ARDS patients, EMGdi was slightly decreased after prolonged PPV. This is contrary to the change in diaphragm electromyography during normal body position changes. Monitoring EMGdi regularly during PPV in ARDS patients is feasible and can be used as a reference for lung protective ventilation strategies.

Evaluation of carbon dioxide rebreathing during exercise assisted by noninvasive ventilation with plateau exhalation valve.

Noninvasive ventilation with a plateau exhalation valve (PEV) is often used as an adjunct to exercise to achieve a physiologic training effect in severe chronic obstructive pulmonary disease (COPD) patients. However, during exercise, with the increase of exhalation flow and respiratory rate and limited capability of PEV to exhale gases out of the circuit, it is still unknown whether CO2 rebreathing occurs in COPD patients ventilated during exercise assisted by single-limb circuit with a PEV. A maximal symptom-limited cycle exercise test was performed while ventilated on pressure support (inspiratory:expiratory pressure 14:4 cmH2O) in 18 male patients with stable severe COPD (mean ± standard deviation, forced expiratory volume in 1 s: 29.5%±6.9% predicted). At rest and during exercise, breathing pattern, mean expiratory flow, mean expiratory flow of PEV, and the mean inspiratory fraction of CO2 (tidal fractional concentration of inspired CO2 [FiCO2]) reinsufflated from the circuit was measured for each breath. In comparison with rest, with the significant increase of mean expiratory flow (0.39±0.15 vs 0.82±0.27 L/s), fractional concentration of end-tidal CO2 (2.6%±0.7% vs 5.5%±0.6%), and the significant decrease of mean expiratory flow of PEV (0.41±0.02 vs 0.39±0.03 L/s), tidal FiCO2 significantly increased at peak exercise (0.48%±0.19% vs 1.8%±0.6%) in patients with stable severe COPD. The inflection point of obvious CO2 rebreathing was 0.67±0.09 L/s (95% confidence interval 0.60-0.73 L/s). Ventilated by a single-limb tubing with PEV caused CO2 rebreathing to COPD patients during exercise. Patients with mean expiratory flow >0.60-0.73 L/s may be predisposed to a higher risk of CO2 rebreathing.

Efficacy of non-invasive ventilation as a rescue therapy for relieving dyspnea in patients with stable severe COPD.

Exertional Dyspnea is a troublesome symptom in chronic obstructive pulmonary disease (COPD) even after optimal therapy, which is a physiological and perceptional burden to limit their activities. Non-invasive ventilation (NIV) might provide rescue therapy for this population to relieve exertional dyspnea. This was a randomized crossover study in 18 patients with stable severe COPD. Exertional dyspnea was induced with maximal symptom-limited incremental cycle exercise. Then the patients would randomly receive oxygen or NIV plus oxygen therapy. Patients were crossed to another therapy in the second day. During the whole process, breathing pattern were monitored continuously until complete recovery. At every 30s interval, inspiratory capacity (IC) and Borg scale were assessed. Changes were compared between two interventions. Compared with oxygen therapy, NIV plus oxygen therapy resulted in increase of tidal volume and minute ventilation, decrease in dyspnea intensity at isotime (reduction of 1.0 ± 2.0 Borg units, p < 0.05) and a tendency but not statistically significant shortening in total dyspnea recovery time (326.2 ± 132.0s vs 356.5 ± 156.9s, p = 0.225). These improvements were negatively correlated with baseline FEV1 (r = -0.617, p < 0.01). Subjects were divided into responders (n = 9) with dyspnea recovery time shortening > 30s or non-responders. Responder subgroup had significantly poorer pulmonary function in FEV1, FEV1%, IC than non-responder subgroup, indicating that NIV is effective as rescue therapy for exertional dyspnea in stable COPD with poorer pulmonary function. NIV as rescue therapy could help relieve dyspnea after exercise in patients with stable severe COPD with a poor pulmonary function.

Inflammatory Responses, Spirometry, and Quality of Life in Subjects With Bronchiectasis Exacerbations.

BACKGROUND: Bronchiectasis exacerbations are critical events characterized by worsened symptoms and signs (ie, cough frequency, sputum volume, malaise). OBJECTIVES: Our goal was to examine variations in airway and systemic inflammation, spirometry, and quality of life during steady state, bronchiectasis exacerbations, and convalescence (1 week following a 2-week antibiotic treatment) to determine whether potentially pathogenic microorganisms, including Pseudomonas aeruginosa, were associated with poorer conditions during bronchiectasis exacerbations. METHODS: Peripheral blood and sputum were sampled to detect inflammatory mediators and bacterial densities. Spirometry and quality of life (St George Respiratory Questionnaire [SGRQ]) were assessed during the 3 stages. RESULTS: Forty-eight subjects with bronchiectasis (43.2 ± 14.2 y of age) were analyzed. No notable differences in species and density of potentially pathogenic microorganisms were found during bronchiectasis exacerbations. Except for CXCL8 and tumor necrosis factor alpha (TNF-α), serum inflammation was heightened during bronchiectasis exacerbations and recovered during convalescence. Even though sputum TNF-α was markedly higher during bronchiectasis exacerbations and remained heightened during convalescence, the variations in miscellaneous sputum markers were unremarkable. Bronchiectasis exacerbations were associated with notably higher SGRQ symptom and total scores, which recovered during convalescence. FVC, FEV1, and maximum mid-expiratory flow worsened during bronchiectasis exacerbations (median change from baseline of -2.2%, -0.8%, and -1.3%) and recovered during convalescence (median change from baseline of 0.6%, 0.7%, and -0.7%). Compared with no bacterial isolation, potentially pathogenic microorganism or P. aeruginosa isolation at baseline did not result in poorer clinical condition during bronchiectasis exacerbations. CONCLUSIONS: Bronchiectasis exacerbations are characterized by heightened inflammatory responses and poorer quality of life and spirometry, but not by increased bacterial density, which applies for subjects with and without potentially pathogenic microorganism isolation when clinically stable. (ClinicalTrials.gov registration NCT01761214.).

Aetiology of bronchiectasis in Guangzhou, southern China.

BACKGROUND AND OBJECTIVE: Aetiologies of bronchiectasis in mainland China and their comparisons with those in western countries are unknown. We aimed to investigate bronchiectasis aetiologies in Guangzhou, southern China, and to determine ethnic or geographic differences with reports from western countries. METHODS: Consecutive patients with steady-state bronchiectasis were randomly recruited. Past history was meticulously extracted. Patients underwent physical examination, saccharine test, humoral immunity assays, gastroesophageal reflux scoring and sputum culture. Fiberoptic bronchoscopy, total immunoglobin E (IgE) and Aspergillus fumigatus-specific IgE measurement, 24-h gastroesophageal pH monitoring and miscellaneous screening tests were performed, if indicated. This entailed comparisons on aetiologies with literature reports. RESULTS: We enrolled 148 patients (44.6 ± 13.8 years, 92 females), most of whom had mild to moderate bronchiectasis. Idiopathic (46.0%), post-infectious (27.0%) and immunodeficiency (8.8%) were the most common aetiologies. Miscellaneous aetiologies consisted of asthma (5.4%), gastroesophageal reflux (4.1%), aspergillosis (2.7%), congenital lung malformation (2.0%), Kartagener syndrome (1.4%), rheumatoid arthritis (1.4%), chronic obstructive pulmonary disease (0.7%), Young's syndrome (0.7%), yellow nail's syndrome (0.7%), eosinophilic bronchiolitis (0.7%) and foreign bodies (0.7%). No notable differences in clinical characteristics between idiopathic and known aetiologies were found. Ethnic or geographic variations of aetiologies were overall unremarkable. CONCLUSIONS: Idiopathic, post-infectious and immunodeficiency constitute major bronchiectasis aetiologies in Guangzhou. Clinical characteristics of patients between known aetiologies and idiopathic bronchiectasis were similar. Ethnicity and geography only account for limited differences in aetiologic spectra. These findings will offer rationales for early diagnosis and management of bronchiectasis in future studies and clinical practice in China.

Impulse oscillometry in adults with bronchiectasis.

RATIONALE: The usefulness of impulse oscillometry (IOS) in bronchiectasis has not been systematically investigated. OBJECTIVES: To determine the usefulness of IOS parameters and their correlation with radiology, disease severity, sputum bacteriology, and spirometry, and to compare the changes in IOS parameters during exacerbations and convalescence of bronchiectasis. METHODS: We recruited 100 patients with bronchiectasis and 28 healthy subjects. Receiver operating characteristic curve was plotted to analyze the diagnostic performance of IOS parameters. Chest high-resolution computed tomography (HRCT), Bronchiectasis Severity Index (BSI) assessment, sputum culture, and spirometry were performed. Correlation between IOS parameters and clinical indices was determined using the Spearman model. Changes in IOS parameters, compared with spirometry, during exacerbation were assessed in 16 patients with bronchiectasis. MEASUREMENTS AND MAIN RESULTS: IOS parameters (in particular, resonant frequency) could discriminate patients with bronchiectasis from healthy subjects. Higher levels of IOS parameters were associated with Pseudomonas aeruginosa infection, dyshomogeneity, higher BSI and HRCT score, more bronchiectatic lobes, and cystic bronchiectasis (all P < 0.05). All IOS parameters but lung resistance at 5 Hz were positively correlated with the duration of bronchiectasis symptoms, number of bronchiectatic lobes, HRCT total scores, and BSI (all P < 0.05), but not sputum bacterial density (P > 0.05). IOS parameters, but not spirometric parameters, were not statistically different between peripheral and peripheral plus central segment bronchiectasis (all P > 0.05). Increased frequency dependence (higher resonance frequency or reactance area) was more likely to be associated with lower HRCT scores (≤5) than FEV1. Compared with FEV1, any single IOS parameter being abnormal was more common in mild bronchiectasis, particularly in patients with HRCT score of 5 or lower. IOS parameters were not statistically different from baseline to exacerbations and convalescence (all P > 0.05). CONCLUSIONS: IOS parameters correlate with clinical indices and could reflect peripheral airway abnormality. An increased number of aberrant IOS parameters signals poorer clinical conditions. Increased frequency dependence might be a sensitive marker of mild bronchiectasis. Any single IOS parameter being abnormal sensitively reflects mild bronchiectasis. IOS parameters do not change significantly during bronchiectasis exacerbations. Clinical Trial registered with www.clinicaltrials.gov (NCT01761214).

Six-minute walk test in Chinese adults with clinically stable bronchiectasis: association with clinical indices and determinants.

BACKGROUND: The profiles of 6-minute walk distance (6MWD) in adults with clinically stable bronchiectasis in Chinese adult patients with bronchiectasis are unclear. OBJECTIVES: To delineate the 6MWD by stratification of clinical indices, and to investigate the factors associated with reduced 6MWD in Chinese adults with clinically stable bronchiectasis. METHODS: We recruited 141 adult bronchiectasis patients (mean age: 44.3 ± 13.9 years). Demography, radiology, spirometry, diffusing capacity, etiology, sputum bacteriology, modified Medical Research Council dyspnea scale (MMRC) and quality of life were assessed. The safety profile of the measurement was also examined. RESULTS: Lower levels of 6MWD were associated with older age (>50 years), higher HRCT total score, presence of cystic bronchiectasis, bilateral bronchiectasis, reduced diffusing capacity, higher MMRC score, and higher SGRQ scores. Correlation coefficients between 6MWD and spirometry and quality of life scores were different in patients with 6MWD higher and lower than lower limit of normal. DLCO being less than 80% predicted (OR = 3.13, 95% CI: 1.32-7.43, P = 0.01) and MMRC scale between 1 and 4 (OR = 6.42, 95% CI: 2.27-18.18, P < 0.01) were the factors associated with 6MWD being less than the lower limit of normal (80% predicted value). No severe adverse events were reported. CONCLUSION: The 6MWD could be safely measured in adult patients with bronchiectasis and is poorly associated with clinical parameters. DLCO less than 80% predicted and higher MMRC scale are independent predictors of 6MWD below the lower limit of normal. Our findings will provide a reference for management of bronchiectasis patients in mainland China.

The role of viral infection in pulmonary exacerbations of bronchiectasis in adults: a prospective study.

BACKGROUND: Although viral infections are a major cause of exacerbations in patients with chronic airway diseases, their roles in triggering bronchiectasis exacerbations in adults remain unclear. Therefore, we prospectively investigated the incidence and clinical impacts of viral infection in adults with bronchiectasis exacerbations. METHODS: The study cohort of 119 adults with bronchiectasis was followed up prospectively for 12 months. Nasopharyngeal swabs and sputum samples were assayed for 16 respiratory viruses, using polymerase chain reaction assays. Symptoms, spirometry, quality of life, bacterial cultures, and inflammatory markers were assessed during steady-state bronchiectasis and exacerbations. RESULTS: A total of 100 exacerbations were captured from 58 patients during 1-year follow-up. Respiratory viruses were found more frequently in nasopharyngeal swabs and sputum during bronchiectasis exacerbations (49 of 100, 49.0%) than during steady state (11 of 58, 18.9%; P < .001). The most common viruses found in patients experiencing exacerbations were coronavirus (19 of 65, 39.2%), rhinovirus (16 of 65, 24.6%), and influenza A/B viruses (16 of 65, 24.6%). Virus-positive exacerbations were associated with a greater increase in markers of systemic and airway inflammation (serum IL-6 and tumor necrosis factor-α; sputum IL-1ß and tumor necrosis factor-α) compared with virus-negative exacerbations, but the differences in spirometric indexes, quality of life, and bacterial density were unremarkable. In receiver operating characteristics analysis, serum interferon-γ-induced protein 10 yielded an area under curve of 0.67 (95% CI, 0.53-0.77; P = .018). Furthermore, a greater proportion of patients with virus-positive exacerbations received IV antibiotics. CONCLUSIONS: Prevalence of viral infections, detected by polymerase chain reaction assay, is higher in cases of bronchiectasis exacerbations than in steady-state bronchiectasis, suggesting that respiratory viruses play crucial roles in triggering bronchiectasis exacerbations. The potential mechanisms of virus-induced bronchiectasis exacerbations merit further investigations. TRIAL REGISTRY: ClinicalTrials.gov; No.: NCT01801657; www.clinicaltrials.gov.

Characterization of lung function impairment in adults with bronchiectasis.

BACKGROUND: Characteristics of lung function impairment in bronchiectasis is not fully understood. OBJECTIVES: To determine the factors associated with lung function impairment and to compare changes in spirometry during bronchiectasis exacerbation and convalescence (1 week following 14-day antibiotic therapy). METHODS: We recruited 142 patients with steady-state bronchiectasis, of whom 44 with acute exacerbations in the follow-up were included in subgroup analyses. Baseline measurements consisted of chest high-resolution computed tomography (HRCT), sputum volume, purulence and bacteriology, spirometry and diffusing capacity. Spirometry, but not diffusing capacity, was examined during acute exacerbations and convalescence. RESULTS: In the final multivariate models, having bronchiectasis symptoms for 10 years or greater (OR = 4.75, 95%CI: 1.46-15.43, P = 0.01), sputum culture positive for Pseudomonas aeruginosa (OR = 4.93, 95%CI: 1.52-15.94, P<0.01) and HRCT total score being 12 or greater (OR = 7.77, 95%CI: 3.21-18.79, P<0.01) were the major variables associated with FEV1 being 50%pred or less; and the only variable associated with reduced DLCO was 4 or more bronchiectatic lobes (OR = 5.91, 95%CI: 2.20-17.23, P<0.01). Overall differences in FVC and FEV1 during exacerbations and convalescence were significant (P<0.05), whereas changes in other spirometric parameters were less notable. This applied even when stratified by the magnitude of FEV1 and DLCO reduction at baseline. CONCLUSION: Significant lung function impairment should raise alert of chest HRCT abnormality and sputum culture positive for Pseudomonas aeruginosa, in patients with predominantly mild to moderate steady-state bronchiectasis. Acute exacerbations elicited reductions in FVC and FEV1. Changes of other spirometric parameters were less significant during exacerbations. TRIAL REGISTRATION: ClinicalTrials.gov NCT01761214.

Capsaicin cough sensitivity and the association with clinical parameters in bronchiectasis.

BACKGROUND: Cough hypersensitivity has been common among respiratory diseases. OBJECTIVE: To determine associations of capsaicin cough sensitivity and clinical parameters in adults with clinically stable bronchiectasis. METHODS: We recruited 135 consecutive adult bronchiectasis patients and 22 healthy subjects. History inquiry, sputum culture, spirometry, chest high-resolution computed tomography (HRCT), Leicester Cough Questionnaire scoring, Bronchiectasis Severity Index (BSI) assessment and capsaicin inhalation challenge were performed. Cough sensitivity was measured as the capsaicin concentration eliciting at least 2 (C2) and 5 coughs (C5). RESULTS: Despite significant overlap between healthy subjects and bronchiectasis patients, both C2 and C5 were significantly lower in the latter group (all P<0.01). Lower levels of C5 were associated with a longer duration of bronchiectasis symptoms, worse HRCT score, higher 24-hour sputum volume, BSI and sputum purulence score, and sputum culture positive for P. aeruginosa. Determinants associated with increased capsaicin cough sensitivity, defined as C5 being 62.5 µmol/L or less, encompassed female gender (OR: 3.25, 95%CI: 1.35-7.83, P<0.01), HRCT total score between 7-12 (OR: 2.57, 95%CI: 1.07-6.173, P = 0.04), BSI between 5-8 (OR: 4.05, 95%CI: 1.48-11.06, P<0.01) and 9 or greater (OR: 4.38, 95%CI: 1.48-12.93, P<0.01). CONCLUSION: Capsaicin cough sensitivity is heightened in a subgroup of bronchiectasis patients and associated with the disease severity. Gender and disease severity, but not sputum purulence, are independent determinants of heightened capsaicin cough sensitivity. Current testing for cough sensitivity diagnosis may be limited because of overlap with healthy subjects but might provide an objective index for assessment of cough in future clinical trials.

Macrolide therapy in adults and children with non-cystic fibrosis bronchiectasis: a systematic review and meta-analysis.

BACKGROUND: A systematic review and meta-analysis was conducted to evaluate the efficacy and safety of macrolide therapy in adults and children with bronchiectasis. METHODS: We searched the PUBMED, EMBASE, CENTRAL databases to identify relevant studies. Two reviewers evaluated the studies and extracted data independently. The primary outcome was the number of bronchiectasis exacerbations. Secondary outcomes included exacerbation-related admissions, quality of life (QoL), spirometry, 6-minute walk test (6MWT) and adverse events. RESULTS: Nine eligible trials with 559 participants were included. Six were conducted on adults, and the remaining on children. Macrolide therapy significantly reduced the number of patients experiencing one or more exacerbation in adults [risk ratio (RR) = 0.59; 95% CI, 0.40 to 0.86; P = 0.006; I2 = 65%] and children [RR = 0.86; 95% CI, 0.75-0.99; P = 0.04; I2 = 0%], but not the number of patients with admissions for exacerbation. Macrolide therapy was also associated with reduced frequency of exacerbations in adults (RR = 0.42; 95% CI, 0.29 to 0.61; P<0.001; I2 = 64%) and children (RR = 0.50; 95% CI, 0.35 to 0.71; P<0.001). Pooled analyses suggested that spirometry, including FEV1 and FVC, were significantly improved in adults but not in children. Macrolide therapy improved the QoL (WMD, -6.56; 95% CI, -11.99 to -1.12; P = 0.02; I2 = 86%) but no significant difference in 6MWT (WMD, 4.15; 95% CI, -11.83 to 20.13; P = 0.61; I2 = 31%) and the overall adverse events (RR, 0.96; 95% CI, 0.82 to 1.13; P = 0.66; I2 = 0%) in adults. However, reports of diarrhea and abdominal discomforts were higher with macrolide therapy. CONCLUSIONS: Macrolide maintenance therapy, both in adults and children, was effective and safe in reducing bronchiectasis exacerbations, but not the admissions for exacerbations. In addition, macrolide administration in adults was associated with improvement in QoL and spirometry, but not 6WMT. Future studies are warranted to verify the optimal populations and clarify its potential effects on antimicrobial resistance.

[Effect of dexmedetomidine on postoperative analgesia and sedation in pediatric patients undergoing cleft lip and palate repair].

OBJECTIVE: To explore the effect of different doses of dexmedetomidine on the sedation of recovery period and the postoperative early pain scores in pediatric patients undergoing cleft lip and palate repair. METHODS: A total of 100 American Society of Anesthesiologists (ASA) I-II pediatric patients undergoing cleft lip and palate repair were randomly divided into 5 groups (D1, D2, D3, D4 and C, n = 20 each). Groups D1-D4 received a continuous pump infusion of dexmedetomidine at 0.25, 0.5, 0.75, 1.0 µg × kg(-1)× h(-1) respectively for 1 h before the completion of operation. Then an intravenous injection of 1 µg/kg was prescribed over 10 min as a loading dose. Group C, taken as control, received an equal volume of normal saline. Propofol 2 mg/kg was added for the occurrence of emergence agitation. Mean arterial pressure (MAP), heart rate (HR), respiratory rate (RR), partial pressure of end-tidal carbon dioxide (P(ET)CO(2)), Riker sedation-agitation scale, times of additional propofol requirements, times of additional artificial ventilation, extubation time, discharge time, side effects and face, legs, activity, cry and consolability (FLACC) scale were observed and recorded. RESULTS: The Riker sedation-agitation scale were 5.3 ± 0.9, 4.3 ± 0.8, 3.5 ± 0.8, 2.6 ± 0.6 and 6.1 ± 0.7, times of additional propofol requirements were 4.7 ± 1.7, 2.5 ± 1.4, 0.8 ± 0.9, 0.1 ± 0.4 and 5.7 ± 0.7 in groups D1, D2, D3, D4 and C respectively. In short, group D4 ≈ group D3 < group D2 < group D1 < group C (P < 0.05). As compared with group D4, the extubation time and discharge time significantly increased in groups D1, D2, D3 and C (P < 0.05). The FLACC scales in groups D2, D3 and D4 were lower than those in groups D1 and C. Side effects: 2 cases developed sinus bradycardia in group D4 and heart rate returned to normal after treatment. CONCLUSION: At a load dosage of 1 µg/kg and a maintenance dosage of 0.75 µg × kg(-1)× h(-1), dexmedetomidine shows excellent effects on the recovery period of cleft lip and palate repairing in pediatric patients. The FLACC scale decreases with fewer side effects, but extubation time and discharge time increase.

Effect of mixed crowding on refolding of human muscle creatine kinase.

The effects of mixed crowding agents containing both sucrose and dextran 70 on refolding process of human muscle creatine kinase (HCK) were studied by enzyme activity assay and aggregation measurements. The results showed that sucrose and dextran have opposite effect on parameters of HCK during refolding: reactivation yield, refolding rates and amount of aggregation, as they were both used in the mixed crowding agents. The exclusion volume effect of dextran and osmophobic effect of sucrose on HCK refolding can be counteracted by each other: sucrose bated the aggregation induced by dextran and increased the final reactivation yield and refolding rate of the slow track, while dextran inhibited the effect of sucrose to prevent aggregation and help correct folding. The effects of human cyclophilin 18 (hCyp18) and casein on folding of HCK were also studied in crowding conditions, and it was found that the chaperone function of hCyp18 was additive with sucrose but blocked by dextran, and that the aggregation-improving effect of casein was additive with dextran 70 but impaired by sucrose to certain extent. This study indicates osmolytes and macromolecule crowding agents play different roles in the physiological conditions and could lead to better understanding of protein folding in the intracellular environment.