BACKGROUND: Organic chemicals have been known to cause allergic diseases such as bronchial asthma and hypersensitivity pneumonitis; however, the possibility that they do not cause irreversible pulmonary fibrosis has not been considered. Polyacrylic acid (PAA), an organic chemical, has caused irreversible progressive pulmonary fibrosis in exposed workers, indicating its potential to induce pulmonary inflammation and fibrosis. Although intratracheal instillation studies are commonly used for evaluating lung pathology, traditional methods face challenges with chemical substances, particularly nanoparticles, which tend to aggregate in suspension and prevent uniform pulmonary distribution. Such aggregation alters the qualitative and quantitative responses to lung injury, limiting accurate assessment of lung pathology. To overcome this limitation, we developed a 'molecular dispersion method' that uses pH modification to negative charges to PAA particles, maintaining their dispersion. Using this method, we investigated the effects of PAA on pulmonary inflammation and fibrosis in a rat model. METHODS: F344 rats were intratracheally instilled with PAA using molecular dispersion (0.1 mg/rat, 1.0 mg/rat), PAA without molecular dispersion (1.0 mg/rat), and normal saline (control group). Rats were sacrificed at 3 days, 1 week, 1 month, 3 months, and 6 months after exposure to examine inflammatory and fibrotic responses. RESULTS: PAA caused persistent increases in neutrophil influx in the bronchoalveolar lavage fluid (BALF) from 3 days to 1 month following instillation. In histopathological findings, the group with molecular dispersion had almost no inflammatory masses in the lung tissue compared to the group without molecular dispersion, and exhibited relatively uniform dispersion. CONCLUSION Intratracheal instillation of dispersed PAA induced neutrophil inflammation and fibrosis in the rat lung, suggesting that PAA might have pulmonary inflammogenicity and fibrogenicity. Intrapulmonary dispersion of PAA particles following intratracheal instillation studies using the molecular dispersion method was similar to that following inhalation studies.
Animals ; Rats, Inbred F344 ; Acrylic Resins/adverse effects* ; Rats ; Inhalation Exposure/adverse effects* ; Male ; Pulmonary Fibrosis/pathology* ; Pneumonia/pathology* ; Lung/pathology* ; Bronchoalveolar Lavage Fluid/cytology*

Introduction：Respiratory failures are categorized into types I and II. To our knowledge, we report the first case of pulmonary rehabilitation in a patient with systemic sclerosis/polymyositis overlap syndrome who developed type II respiratory failure.Methods：The patient was a 77-year-old woman who had received treatment for systemic sclerosis and polymyositis at another hospital. When she visited our hospital to obtain a second opinion, she suddenly lost consciousness and underwent trachea intubation because of typeⅡrespiratory failure. She received physical therapy on the third day of hospitalization and underwent a tracheotomy on the 16th day. As her thoracic movement was markedly restricted, we started physical training. After she was weaned off from the ventilator on the 43rd day, we performed muscular strength training and aerobic exercise. No exacerbation of CO2 storage was observed even if chest motion training was performed. She was discharged on the 72nd day and advised to wear retina®．Administration of therapeutic drugs such as steroids was maintained at the same dose.Conclusion：Physical therapy, such as chest mobilization, was effective for marked restriction of chest movement in a patient who had both polymyositis and systemic sclerosis.

Introduction：Respiratory failures are categorized into types I and II. To our knowledge, we report the first case of pulmonary rehabilitation in a patient with systemic sclerosis/polymyositis overlap syndrome who developed type II respiratory failure.Methods：The patient was a 77-year-old woman who had received treatment for systemic sclerosis and polymyositis at another hospital. When she visited our hospital to obtain a second opinion, she suddenly lost consciousness and underwent trachea intubation because of typeⅡrespiratory failure. She received physical therapy on the third day of hospitalization and underwent a tracheotomy on the 16th day. As her thoracic movement was markedly restricted, we started physical training. After she was weaned off from the ventilator on the 43rd day, we performed muscular strength training and aerobic exercise. No exacerbation of CO2 storage was observed even if chest motion training was performed. She was discharged on the 72nd day and advised to wear retina®．Administration of therapeutic drugs such as steroids was maintained at the same dose.Conclusion：Physical therapy, such as chest mobilization, was effective for marked restriction of chest movement in a patient who had both polymyositis and systemic sclerosis.

Objective: To clarify factors related to emotional instability in spouses of cancer patients receiving palliative chemotherapy. Methods: Semi-structured interviews were conducted with spouses of cancer patients receiving palliative chemotherapy, and the obtained data were qualitatively and inductively analyzed. Results: Through analysis, 9 related factors were identified: “realizing the severity of the situation when receiving an explanation of the pathological condition”, “an unclear prognosis”, “fear of losing any treatments”, “being pressed for treatment-related decision-making”, “increased daily burdens by the care”, “collapse the visions of the family future”, “communication with medical professionals”,“candid dialogues with the patient”, and “relationships with others”. Conclusion: It may be important for nurses to help families of cancer patients realistically manage their situation without excessive confusion, even when they experience emotional instability, and spend meaningful time with patients as an outcome of treatment, with an understanding of these related factors on such emotional instability.