Yoshihiro Nishimura

Even with recent advances in pathobiology and treatment options, chronic obstructive pulmonary disease (COPD) remains a major contributor to morbidity and mortality. To develop new ways of combating this disease, breakthroughs in our understanding of its mechanisms are sorely needed. Investigating the involvement of underanalyzed lung cell types, such as endothelial cells (ECs), is one way to further our understanding of COPD. JCAD is a junctional protein in endothelial cells (ECs) arising from the KIAA1462 gene, and a mutation in this gene has been implicated in the risk of developing COPD. In our study, we induced inflammation and emphysema in mice via the global knockout of KIAA1462/JCAD (JCAD-KO) and confirmed it in HPMECs and A549 to examine how the loss of JCAD could affect COPD development. We found that KIAA1462/JCAD loss reduced acute lung inflammation after elastase treatment. Even after 3 weeks of elastase, JCAD-KO mice demonstrated a preserved lung parenchymal structure and vasculature. In vitro, after KIAA1462 expression is silenced, both endothelial and epithelial cells showed alterations in pro-inflammatory gene expression after TNF-α treatment. We concluded that JCAD loss could ameliorate COPD through its anti-inflammatory and anti-angiogenic effects, and that KIAA1462/JCAD could be a novel target for COPD therapy.

The respiratory rate is an important factor for assessing patient status and detecting changes in the severity of illness. Real-time determination of the respiratory rate will enable early responses to changes in the patient condition. Several methods of wearable devices have enabled remote respiratory rate monitoring. However, gaps persist in large-scale validation, patient-specific calibration, standardization and their usefulness in clinical practice has not been fully elucidated. The aim of this study was to evaluate the accuracy of 2 wearable stretch sensors, C-STRECH® which is used in clinical practice and a novel stretchable capacitor in measuring the respiratory rate. The respiratory rate of 20 healthy subjects was measured by a spirometer with the stretch sensor applied to 1 of 5 locations (umbilicus, lateral abdomen, epigastrium, lateral chest, or chest) of their body at rest while they were in a sitting or supine position before or after exercise. The sensors detected the largest amplitudes at the epigastrium and umbilicus compared to other sites of measurement for the sitting and supine positions, respectively. At rest, the respiratory rate of the sensors had an error of 0.06 to 2.39 breaths/minute, whereas after exercise, an error of 1.57 to 3.72 breaths/minute was observed compared to the spirometer. The sensors were able to detect the respiratory rate of healthy volunteers in the sitting and supine positions, but there was a need for improvement in detection after exercise.

Purpose: Sleep-disordered breathing is recognized as a comorbidity in patients with idiopathic pulmonary fibrosis (IPF). Among them, nocturnal hypoxemia has been reported to be associated with poor prognosis and disease progression. We developed a diagnostic algorithm to classify nocturnal desaturation from percutaneous oxygen saturation (SpO₂) waveform patterns: sustained pattern, periodic pattern, and intermittent pattern. We then investigated the prevalence of nocturnal desaturation and the association between the waveform patterns of nocturnal desaturation and clinical findings of patients with IPF. Methods: We prospectively enrolled patients with IPF from seven general hospitals between April 2017 and March 2020 and measured nocturnal SpO₂ and nasal airflow by using a home sleep apnea test. An algorithm was used to classify the types of nocturnal desaturation. We evaluated the association between sleep or clinical parameters and each waveform pattern of nocturnal desaturation. Results: Among 60 patients (47 men) who met the eligibility criteria, there were 3 cases with the sustained pattern, 49 cases with the periodic pattern, and 41 cases with the intermittent pattern. Lowest SpO₂ during sleep and total sleep time spent with SpO₂ < 90% were associated with the sustained pattern, and apnea–hypopnea index was associated with the intermittent pattern. Conclusion: We demonstrated the prevalence of each waveform and association between each waveform and sleep parameters in patients with IPF. This classification algorithm may be useful to predict the degree of hypoxemia or the complication of obstructive sleep apnea.

Background: Recent studies have revealed that serpin peptidase inhibitor clade E member 2 (SERPINE2) is associated with tumorigenesis. However, SERPINE2 expression and its role in lung adenocarcinomas are still unknown. Methods: The expression levels of SERPINE2 in 74 consecutively resected lung adenocarcinomas were analyzed by using immunostaining. Inhibition of SERPINE2 expression by small interfering RNA (siRNA) was detected by quantitative PCR. Cell number assays and cell apoptosis assays were performed to clarify the cell-autonomous function of SERPINE2 in A549 and PC9 lung cancer cells. Results: The overall survival of patients with high SERPINE2 expression was significantly worse than that of patients with low SERPINE2 expression (P = 0.0172). Multivariate analysis revealed that SERPINE2 expression was an independent factor associated with poor prognosis (P = 0.03237). The interference of SERPINE2 decreased cell number and increased apoptosis in A549 and PC9 cells Conclusion: These results suggest that SERPINE2 can be used as a novel prognostic marker of lung adenocarcinoma.

In recent years, multitarget drugs for neurological diseases such as Alzheimer’s disease have been developed and well researched. Many studies have revealed that multitarget drugs are also useful for lung cancer and respiratory diseases. Pemetrexed is a multitargeted antifolate with strong antitumor activity against mesothelioma and lung adenocarcinoma. Crizotinib is an ATP-competitive tyrosine kinase inhibitor that targets c-MET, ROS1, and ALK. Alectinib is known as an ALK inhibitor but also targets LTK, CHEK2, FLT3, PHKG2, and RET. Sorafenib is a tyrosine kinase inhibitor that targets RAF kinase, KIT, VEGFR, PDGFR1β, FLT3, and RET. Nintedanib is a multiple tyrosine kinase inhibitor that targets FGFR, PDGFR, and VEGFR. In this review, we summarize the mechanisms of action of multitarget therapies and report the results of the latest clinical trials.

Although immunotherapy has led to durable responses in diverse cancers, unfortunately, there has been limited efficacy and clinical response rates due to primary or acquired resistance to immunotherapy. To maximize the potential of immunotherapy, combination therapy with antiangiogenic drugs seems to be promising. Some phase III trials showed superiority for survival with the combination of immunotherapy and antiangiogenic therapy. In this study, we describe a synergistic mechanism of immunotherapy and antiangiogenic therapy and summarize current clinical trials of these combinations.

The analysis of systematically collected data for COVID-19 infectivity and death rates has revealed in many countries around the world a typical oscillatory pattern with a 7-days (circaseptan) period. Additionally, in some countries the 3.5-days (hemicircaseptan) and 14-days periodicities have been also observed. Interestingly, the 7-days infectivity and death rates oscillations are almost in phase, showing local maxima on Thursdays/Fridays and local minima on Sundays/Mondays. These observations are in stark contrast with a known pattern, correlating the death rate with the reduced medical staff in hospitals on the weekends. One possible hypothesis addressing these observations is that they reflect a gradually increasing stress with the progressing week, which can trigger the maximal death rates observed on Thursdays/Fridays. Moreover, assuming the weekends provide the likely time for new infections, the maximum number of new cases might fall again on Thursdays/Fridays. These observations deserve further study to provide better understanding of the COVID-19 dynamics.

Asthma is an important issue not only in health but also in economics worldwide. Therefore, asthma animal models have been frequently used to understand the pathogenesis of asthma. Recently, in addition to acquired immunity, innate immunity has also been thought to be involved in asthma. Among innate immune cells, group 2 innate lymphoid cells (ILC2s) have been considered to be crucial for eosinophilic airway inflammation by releasing T helper 2 cytokines. Moreover, house dust mites (HDMs) belonging to group 1 act on airway epithelial cells not only as allergens but also as cysteine proteases. The production of interleukin-25 (IL-25), IL-33, and thymic stromal lymphopoietin (TSLP) from airway epithelial cells was induced by the protease activity of HDMs. These cytokines activate ILC2s, and activated ILC2s produce IL-5, IL-9, IL-13, and amphiregulin. Hence, the HDM-induced asthma mouse model greatly contributes to understanding asthma pathogenesis. In this review, we highlight the relationship between ILC2s and the HDM in the asthma mouse model to help researchers and clinicians not only choose a proper asthma mouse model but also to understand the molecular mechanisms underlying HDM-induced asthma.

Introduction: Long-term oxygen therapy is reported to improve hypoxemia and survival in patients with respiratory failure. The demand oxygen delivery system (DODS) saves oxygen and extends the usable time of an oxygen cylinder 2- to 3-fold. A portable oxygen concentrator with an auto-DODS has been developed to switch its sensitivity among 3 levels (standard, high, and extra high) and to supply pulsed-flow oxygen when it detects apnea. The aim of this study is to evaluate the efficacy of this newly developed portable oxygen concentrator with auto-DODS compared to the efficacy of conventional DODS in oxygenation. Methods and analysis: Twenty-six patients with chronic obstructive pulmonary disease or interstitial pneumonia will be randomized to use auto-DODS or conventional DODS at rest and during a 6-minute walk test. Primary endpoints are mean oxygen saturation (SpO₂) at rest and during the 6-minute walk test. Secondary endpoints are the ratios of the times during which the oxygen concentrator operates at each sensitivity mode (standard, high, and extra high) and at a constant pulse rate to the examination time, the ratio of the times during which SpO₂ fall below 90% to the examination time, the lowest value of SpO₂ during the examination time, the mean and highest pulse rates during the examination time, 6-minute walking distance, recovery time, Borg scale, comfort, and reliability, which are measured by a numerical rating scale and a questionnaire, respectively. Ethics and dissemination: The study was conducted in accordance with the Declaration of Helsinki and was registered on Aug 23, 2019 (https://jrct.niph.go.jp/en-latest-detail/jRCTs052190041). The results of the study will be presented at academic conferences and submitted to a peer-reviewed journal. Trial registration number: jRCTs052190041