Reference values of diffusing capacity of non-smoking Chinese in Hong Kong

Anti-TL1A monoclonal antibody modulates the dysregulation of Th1/Th17 cells and attenuates granuloma formation in sarcoidosis by inhibiting the PI3K/AKT signaling pathway

Sarcoidosis is a systemic granulomatous disease characterized by non-caseating epithelioid cell granulomas. One of its immunological hallmarks is the differentiation of CD4 + naïve T cells into Th1/Th17 cells, accompanied by the release of numerous pro-inflammatory cytokines. The TL1A/DR3 signaling pathway plays a crucial role in activating effector lymphocytes, thereby triggering pro-inflammatory responses. The primary aim of this investigation was to scrutinize the impact of anti-TL1A monoclonal antibody on the dysregulation of Th1/Th17 cells and granuloma formation in sarcoidosis. Initially, the abnormal activation of the TL1A/DR3 signaling pathway in pulmonary tissues of sarcoidosis patients was confirmed using qPCR and immunohistochemistry techniques. Subsequently, employing a murine model of sarcoidosis, the inhibitory effects of anti-TL1A monoclonal antibody on the TL1A/DR3 signaling pathway in sarcoidosis were investigated through qPCR, immunohistochemistry, and Western blot experiments. The influence of anti-TL1A monoclonal antibody on granulomas was assessed through HE staining, while their effects on sarcoidosis Th1/Th17 cells and associated cytokine mRNA levels were evaluated using flow cytometry and qPCR, respectively. Immunofluorescence and Western blot experiments corroborated the inhibitory effects of anti-TL1A monoclonal antibody on the aberrant activation of the PI3K/AKT signaling pathway in sarcoidosis. The findings of this study indicate that the TL1A/DR3 signaling pathway is excessively activated in sarcoidosis. Anti-TL1A monoclonal antibody effectively inhibit this abnormal activation in sarcoidosis, thereby alleviating the dysregulation of Th1/Th17 cells and reducing the formation of pulmonary granulomas. This effect may be associated with the inhibition of the downstream PI3K/AKT signaling pathway. Anti-TL1A monoclonal antibody hold promise as a potential novel therapeutic intervention for sarcoidosis.

Referential equations for pulmonary diffusing capacity using GAMLSS models derived from Japanese individuals with near-normal lung function

Objective

To generate appropriate reference values for the single-breath diffusing capacity of the lungs for carbon monoxide (D_LCO), alveolar volume (V_A), and the transfer coefficient of the lungs for carbon monoxide (K_CO, often denoted as D_LCO/V_A) in the Japanese population. We also intended to assess the applicability of these values for the Japanese population by comparing them to those published by the Global Lung Function Initiative in 2017 (GLI-2017) and previous values.

Methods

In this retrospective study, we measured the spirometric indices, D_LCO, V_A, and K_CO of the Japanese population aged 16–85 years. The lambda, mu, and sigma (LMS) method and the generalized additive models for the location, scale, and shape program in R were used to generate the reference values.

Results

We conducted a total of 390 tests. The GLI-2017 z-scores of D_LCO were approximately zero, whereas those of K_CO and V_A were far from zero. In the present study, the mean square errors of the D_LCO, V_A, and K_CO reference values were lower than the reference values derived from GLI-2017 and previous linear regression equations.

Conclusions

Reference values obtained in this study were more appropriate for our sample than those reported in GLI-2017. Differences between the two equations were attributed to underestimating K_CO (D_LCO / V_A) and overestimating V_A, respectively, by the GLI-2017 for the Japanese population.

The need for race-specific reference equations for pulmonary diffusing capacity for nitric oxide

BACKGROUND

Few reference equations exist for healthy adults of various races for pulmonary diffusing capacity for nitric oxide (DLNO). The purpose of this study was to collect pilot data to demonstrate that race-specific reference equations are needed for DLNO.

METHODS

African Americans (blacks) were chosen as the comparative racial group. In 2016, a total of 59 healthy black subjects (27 males and 32 females) were recruited to perform a full battery of pulmonary function tests. In the development of DLNO reference equations, a white reference sample (randomly drawn from a population) matched to the black sample for sex, age, and height was used. Multiple linear regression equations for DLNO, alveolar volume (VA), and pulmonary diffusing capacity for carbon monoxide (DLCO) using a 5-6 s breath-hold were developed.

RESULTS

Our models demonstrated that sex, age2, race, and height explained 71% of the variance in DLNO and DLCO, with race accounting for approximately 5-10% of the total variance. After normalizing for sex, age2, and height, blacks had a 12.4 and 3.9 mL/min/mmHg lower DLNO and DLCO, respectively, compared to whites. The lower diffusing capacity values in blacks are due, in part, to their 0.6 L lower VA (controlling for sex and height).

CONCLUSION

The results of this pilot data reveal small but important and statistically significant racial differences in DLNO and DLCO in adults. Future reference equations should account for racial differences. If these differences are not accounted for, then the risk of falsely diagnosing lung disease increase in blacks when using reference equations for whites.

Reference Values for Pulmonary Single-Breath Diffusing Capacity - Results of the "Study of Health in Pomerania"

OBJECTIVES

 The assessment of pulmonary single-breath diffusing capacity is a frequently performed diagnostic procedure and considered as an important tool in medical surveillance examinations of pulmonary diseases.The aim of this study was to establish reference equations for pulmonary single-breath diffusing capacity parameters in a representative adult-population across a wide age range and to compare the normative values from this sample with previous ones.

METHODS

 Diffusing capacity measurement was carried out in 3566 participants (1811 males) of a cross-sectional, population-based survey ("Study of Health in Pomerania - SHIP").

RESULTS

 Individuals with cardiopulmonary disorders and current smoking habits were excluded, resulting in 1786 healthy individuals (923 males), aged 20 - 84 years. Prediction equations for both sexes were established by quantile regression analyses, taking into consideration the influence of age, height, weight and former smoking.

CONCLUSION

 The study provides a novel set of prediction equations for pulmonary single-breath diffusing capacity in an adult Caucasian population. The results are comparable to previously reported equations, underline their importance and draw attention to the need for up-to-date reference equations that adequately take into account both the subjects' origin, age, anthropometric characteristics and the equipment used.

Effect of therapeutic arsenic exposure on pulmonary function

AIM

Arsenic-contaminated drinking water has been associated with respiratory diseases and lung function impairment. Oral arsenic trioxide (ATO) is a standard treatment for acute promyelocytic leukaemia. This study aimed to explore the effect of therapeutic exposure to arsenic on lung function.

PATIENTS AND METHOD

This was a case-control cross-sectional study on patients with haematological malignancies with or without exposure to ATO. Full lung function tests and serum Clara cell protein 16 (CC16) were measured.

RESULTS

There were 57 cases (arsenic exposed) and 57 matched controls (arsenic non-exposed) recruited. Among cases, the median duration of ATO exposure was 519 (194-1259) days. The mean FEV(1)/FVC ratio, FEV(1) (% predicted), and RV/TLC (%), as well as % subjects with FEV(1)/FVC below lower limits of normal (LLN), were similar in the two groups with or without arsenic exposure. However the mean TLC (% predicted) and DLCO/VA were significantly higher in arsenic-exposed versus non-exposed group (p = 0.01 and p = 0.008 respectively). There were mildly reduced FEV(1)/FVC ratio and FEF(25-75) (% predicted), largely within normal limits, among high level arsenic exposure compared with non-exposure (p = 0.01 and p = 0.05 respectively). Serum CC16 was comparable among both arsenic exposed and non-exposed groups.

CONCLUSION

Therapeutic use of oral ATO for a median of around 1.5 years was not associated with clinically significant lung function impairment.

Clinical applications of lung function tests: a revisit

The development and clinical application of lung function tests have a long history, and the various components of lung function tests provide very important tools for the clinical evaluation of respiratory health and disease. Spirometry, measurement of the diffusion factor, bronchial provocation tests and forced oscillation techniques have found diverse clinical applications in the diagnosis and monitoring of respiratory diseases, such as chronic obstructive pulmonary disease, interstitial lung diseases and asthma. However, there are some practical issues to be resolved, including the establishment of reference values for individual test parameters and the roles of these tests in preoperative risk assessment and pulmonary rehabilitation. Novel measurements, including negative expiratory pressure, the fraction of exhaled nitric oxide and analysis of exhaled breath condensate, may provide new insights into physiological abnormalities or airway inflammation in respiratory diseases, but their clinical applications need to be further evaluated. The clinical application of lung function tests continues to face challenges, which may be overcome by further improvement of conventional techniques for lung function testing and further specification of new testing techniques.

Lung function testing in health and disease: issues pertaining to Asia-Pacific populations

The Asia-Pacific region comprise of diverse ethnic populations and healthcare systems of highly variable developmental stages. We face challenges in lung function testing, many of which are different from the issues encountered in the west. In some places, access to proper lung function testing facilities is very limited due to resource constraints or geographic inconvenience. It is important to note the potential differences of normative values in Asia-Pacific populations, compared with established values derived from populations of Caucasian ethnicity, hence the need to choose from available prediction formulae the ones that most closely approximate the subjects being tested. The criteria for defining abnormality is a hot topic globally. In the Asia-Pacific region, the trade-off between simplicity and thus ease of application and the pitfall of under- or over-diagnosis based on fixed cut-off values has to be recognized. The promotion of wider availability and proper utilization of lung function testing will go a long way in the enhancement of respiratory health and disease management in the region.

The long-term impact of severe acute respiratory syndrome on pulmonary function, exercise capacity and health status

BACKGROUND AND OBJECTIVE

Severe acute respiratory syndrome (SARS) emerged in 2003 and its long-term sequelae remain largely unclear. This study examined the long-term outcome of pulmonary function, exercise capacity, health and work status among SARS survivors.

METHODS

A prospective cohort study of SARS patients at the Prince of Wales Hospital, Hong Kong was conducted, with serial assessments of lung function, 6MWD and 36 item Short Form General Health Survey at 3, 6, 12, 18 and 24 months after disease onset. The work status was also recorded.

RESULTS

Serial assessments were completed by 55 of the 123 (39.9%) subjects, of whom 27 were health-care workers (HCW). The mean age of the group was 44.4 (SD 13.2) years and 19 (34.5%) were males. At 24 months, 10 (18.2%), 9 (16.4%), 6 (10.9%) and 29 (52.7%) subjects had FEV(1), FVC, TLC and DL(CO) < 80% of predicted values, respectively. The mean (SD) 6MWD increased significantly from 439.0 (89.1) m at 3 months to 460.1 (102.8) m at 6 months (P 0.016) and became steady after 6 months. However, 6MWD and 36 item Short Form General Health Survey scores were lower than the normal population throughout the study. Moreover, 29.6% of HCW and 7.1% of non-HCW had not returned to work 2 years after illness onset.

CONCLUSIONS

This 2-year study of a selected population of SARS survivors, showed significant impairment of DL(CO), exercise capacity and health status persisted, with a more marked adverse impact among HCW.