Publications by authors named "Ichiro Kuwahira"

A 60-year-old man was noted to have an elevated lesion in the right mainstem bronchus on chest computed tomography (CT) during his annual medical checkup 3 years previously. The lesion had gradually increased in size. FDG-PET showed no accumulation.

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Article Synopsis
  • * Chest CT techniques facilitate the study of airway diseases such as COPD and asthma, enabling analysis of local volume changes and other lung structures.
  • * As imaging technologies like dynamic CT, PET/CT, and ultrasound continue to evolve, their applications in diagnosing and managing pulmonary disorders improve, making it crucial for clinicians to stay informed about these methods.
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Background: Numerous studies investigated patients with IPF; however, only a few examined patients with idiopathic interstitial pneumonias (IIPs).

Methods: The Japanese Idiopathic Interstitial Pneumonias (JIPS) Registry, which was initiated in December 2016, is a multicenter prospective observational study of patients newly diagnosed with IIPs from 86 facilities treating ILDs. The plan is to enroll more than 600 new patients during the 2-year enrolment period and to follow their progress for 3 years after the last case enrolment.

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In patients suffering from Coronavirus Disease 2019 (COVID-19), dyspnoea is less likely to occur despite hypoxemia. Even if the patient develops severe hypoxemia, it cannot be detected from subjective symptoms. In other words, it becomes more serious without the person or the surroundings noticing it.

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Article Synopsis
  • The study aimed to assess job stress and burnout among employees at a COVID-19 hospital in Japan before and after the third wave of infections.
  • Surveys were conducted in October 2020 and March 2021 with 151 employees, utilizing the Maslach Burnout Inventory to measure burnout levels.
  • Results indicated 31.1% of employees considered leaving their jobs, with 13.2% experiencing burnout in March 2021, emphasizing the need for ongoing mental health evaluations and targeted interventions to prevent burnout and enhance staff well-being.
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We experienced a case of silent Coronavirus disease 2019 (COVID-19) pneumonia that was found by an optional chest computed tomography (CT) scan during a health check. A 62-year-old man with a present medical history of hypertension visited the health screening center at Tokai University Tokyo Hospital on August 7, 2020. Prior to entry into the hospital, his body temperature was measured and his history was obtained (called 'COVID-19 triage'), but there were no remarkable findings.

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  • He experienced symptoms like low-grade fever, mild hypoxemia, and febrile neutropenia, requiring treatment with granulocyte colony-stimulating factor (G-CSF).
  • After further treatment with hydrocortisone, his condition improved, and his tumors remained stable for 10 months, highlighting potential complications from immune-checkpoint inhibitors during cancer treatment.
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Purpose: Patients with chronic obstructive pulmonary disease (COPD) have decreased physical activity (PA) compared with healthy adults. As lower PA is associated with increased mortality, improving PA is an important objective for COPD management. This large-scale, multicenter, non-interventional, cross-sectional study examined the activity status of COPD patients in Japan and explored factors related to PA.

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Background: The flow-volume (FV) curve pattern in the pulmonary function test (PFT) for obstructive lung diseases is widely recognized. However, there are few reports on FV curve pattern in idiopathic pulmonary fibrosis (IPF). In this study, we investigated the relationship between FV curve pattern and clinical or radiological features in IPF.

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Nitric oxide (NO) is produced in the body and has been shown to have diverse actions in the abundance of research that has been performed on it since the 1970s, leading to Furchgott, Murad, and Ignarro receiving the Nobel Prize in Physiology or Medicine in 1998. NO is produced by nitric oxide synthase (NOS). NOS is broadly distributed, being found in the nerves, blood vessels, airway epithelium, and inflammatory cells.

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Balloon pulmonary angioplasty (BPA) has emerged as a new treatment strategy for patients with chronic thromboembolic pulmonary hypertension (CTEPH). Improvements in hemodynamic parameters after BPA have been reported, but some patients continue to suffer from reduced exercise tolerance even after the normalization of hemodynamic parameters following BPA. As the amelioration of hemodynamic parameters is reportedly achieved via BPA, we hypothesized that the limiting factors for exercise tolerance in these patients are related to respiratory function.

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The objective of this article is to compare and contrast the known characteristics of the systemic O transport of humans, rats, and mice at rest and during exercise in normoxia and hypoxia. This analysis should help understand when rodent O transport findings can-and cannot-be applied to human responses to similar conditions. The O -transport system was analyzed as composed of four linked conductances: ventilation, alveolo-capillary diffusion, circulatory convection, and tissue capillary-cell diffusion.

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A 48-year-old man was referred for evaluation of an abnormal chest shadow noted on a routine chest radiograph during physical examination. He was asymptomatic and had no significant medical history and occupational exposure. The patient lived in Tokyo and had no significant travel history.

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Several new fixed-dose combination bronchodilators have been launched in the world, and 3 different types are now available in Japan. Assessing their efficacy relative to each other has not been performed yet. In the present manuscript, characteristics of glycopyrronium/indacaterol, umeclidinium/vilanterol and tiotropium/olodaterol were reviewed.

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Chronic intermittent hypoxia (IH) induces oxidative stress and inflammation, which impair vascular endothelial function. Long-term insulin resistance also leads to endothelial dysfunction. We determined, in vivo, whether the effects of chronic IH and insulin resistance on endothelial function augment each other.

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Dyspnea consists of various uncomfortable respiratory sensations. It is believed that hypoxia causes dyspnea, but whether hypoxia is a direct dyspnogenic factor remains uncertain. We investigated whether hypoxia has a direct dyspnogenic effect.

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Chronic intermittent hypoxia (IH) induces activation of the sympathoadrenal system, which plays a pivotal role in attenuating hypoxic pulmonary vasoconstriction (HPV) via central β1-adrenergic receptors (AR) (brain) and peripheral β2AR (pulmonary arteries). Prolonged hypercatecholemia has been shown to upregulate β3AR. However, the relationship between IH and β3AR in the modification of HPV is unknown.

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Article Synopsis
  • Pulmonary arterial hypertension (PAH) is commonly found in patients with obstructive sleep apnea syndrome (OSAS), and aging appears to enhance this condition by activating arginase and decreasing nitric oxide (NO) production in arteries.
  • Intermittent hypoxia (IH) plays a role in developing OSAS, and a study using adult and young rats showed that IH induced PAH in adult rats through increased arginase expression and reduced NO, while young rats were unaffected.
  • The research suggests that inhibiting arginase can prevent or reverse the effects of IH-induced PAH in older individuals by normalizing levels of important nitrogen compounds like nitrite and nitrate.
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In sleep apnea syndrome (SAS), intermittent hypoxia (IH) induces repeated episodes of hypoxic pulmonary vasoconstriction (HPV) during sleep, which presumably contribute to pulmonary arterial hypertension (PAH). However, the prevalence of PAH was low and severity is mostly mild in SAS patients, and mild or no right ventricular hypertrophy (RVH) was reported in IH-exposed animals. The question then arises as to why PAH is not a universal finding in SAS if repeated hypoxia of sufficient duration causes cycling HPV.

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Chronic intermittent hypoxia (IH) provokes a centrally mediated increase in sympathetic nerve activity (SNA). Although this sympathetic hyperexcitation has been linked to systemic hypertension, its effect on the pulmonary vasculature is unclear. This study aimed to assess IH-mediated sympathetic excitation in modulating pulmonary vasculature tone, particularly acute hypoxia vasoconstrictor response (HPV), and the central β-adrenergic signaling pathway for facilitating the increase in SNA.

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We present the case of a patient with malignant lymphoma resulting from chronic pyothorax after artificial pneumothorax for pulmonary tuberculosis. The 81-year-old female patient had a medical history of artificial pneumothorax from left pulmonary tuberculosis when she was 23 years old and subsequent chronic pyothorax. She had become aware of pain in the left back from October 2008.

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Sleep apnea syndrome (SAS) is considered to be associated with heart failure (HF). It is known that autophagy is induced in various heart diseases thereby promotes survival, but its excess may be maladaptive. Intermittent hypoxia (IH) plays pivotal role in the pathogenesis of SAS.

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