A polo-like kinase inhibitor identified by computational repositioning attenuates pulmonary fibrosis.

BACKGROUND: Idiopathic pulmonary fibrosis (IPF) is a fatal fibrotic lung disease with few effective therapeutic options. Recently, drug repositioning, which involves identifying novel therapeutic potentials for existing drugs, has been popularized as a new approach for the development of novel therapeutic reagents. However, this approach has not yet been fully utilized in the field of pulmonary fibrosis. METHODS: The present study identified novel therapeutic options for pulmonary fibrosis using a systematic computational approach for drug repositioning based on integration of public gene expression signatures of drug and diseases (in silico screening approach). RESULTS: Among the top compounds predicted to be therapeutic for IPF by the in silico approach, we selected BI2536, a polo-like kinase (PLK) 1/2 inhibitor, as a candidate for treating pulmonary fibrosis using an in silico analysis. However, BI2536 accelerated mortality and weight loss rate in an experimental mouse model of pulmonary fibrosis. Because immunofluorescence staining revealed that PLK1 expression was dominant in myofibroblasts while PLK2 expression was dominant in lung epithelial cells, we next focused on the anti-fibrotic effect of the selective PLK1 inhibitor GSK461364. Consequently, GSK461364 attenuated pulmonary fibrosis with acceptable mortality and weight loss in mice. CONCLUSIONS: These findings suggest that targeting PLK1 may be a novel therapeutic approach for pulmonary fibrosis by inhibiting lung fibroblast proliferation without affecting lung epithelial cells. In addition, while in silico screening is useful, it is essential to fully determine the biological activities of candidates by wet-lab validation studies.

Miliary pulmonary nodules due to Mycobacterium xenopi in a steroid-induced immunocompromised patient successfully treated with chemotherapy: a case report.

BACKGROUND: Mycobacterium xenopi-infected patients have a high prevalence of pulmonary cavities and nodules. However, the clinical course for patients with miliary nodules due to M. xenopi has not yet been reported. CASE PRESENTATION: We encountered a case of miliary nodules with gradually worsening coughing and sputum production in a 44-year-old male who had renal dysfunction due to glomerulosclerosis with a decade-long history of steroid therapy. Although we started anti-tuberculosis treatment on clinical suspicion of miliary tuberculosis, cultures of sputum and bronchial lavage were both positive for M. xenopi. The patient was successfully treated with rifampin, ethambutol and clarithromycin, without fibrosis. It was unclear whether the miliary pattern was induced by hematogenous or endobronchial spread of the M. xenopi infection. CONCLUSION: Even when clinical and radiological disease manifestations are similar to those of miliary tuberculosis, M. xenopi infection should be considered in the differential diagnosis of miliary nodules.

Characteristics of chest high-resolution computed tomography in patients with anti-aminoacyl-tRNA synthetase antibody-positive interstitial lung disease.

BACKGROUND AND AIM: Anti-aminoacyl-tRNA synthetase (ARS) antibodies form a condition called Antisynthetase syndrome (ASSD). While interstitial lung disease (ILD) is a particularly frequent manifestation of ASSD and is closely associated with morbidity and mortality, few studies have been conducted on its characteristics on high-resolution computed tomography (HRCT). In this study, we clarified the HRCT findings in patients with anti-ARS antibody-positive ILD (ARS-ILD).  Methods: The HRCT findings at the time of the ILD diagnosis in 24 ARS-ILD patients were retrospectively evaluated by 2 pulmonologists and one radiologist. We also assessed the clinical symptoms, physical examination findings, and laboratory data including the type of anti-ARS antibodies. For a further analysis, the data of patients were divided into two groups: the polymyositis (PM)/dermatomyositis (DM) group and the non-PM/DM group. RESULTS: The ratio of men to women was almost 1:1. The median age at the time of the diagnosis was 53 years old. Anti-glycyl (anti-EJ) and anti-histidyl (anti-Jo-1) antibodies were more common than others. An analysis of the HRCT patterns of 23 ARS-ILD patients showed that the most common pattern was the nonspecific interstitial pneumonia (NSIP) pattern. The second most common pattern was the usual interstitial pneumonia (UIP) pattern. Between the PM/DM and non-PM/DM groups, no clear trends were noted in the age, sex ratio, proportion of HRCT patterns, or type of anti-ARS antibodies. CONCLUSIONS: This retrospective study demonstrated that ARS-ILD patients, regardless of myositis symptoms, most often showed the NSIP pattern on HRCT, as previously reported. However, unlike previous reports, the UIP pattern on HRCT was not rare.

Isolated Adrenocorticotropic Hormone Deficiency Presenting With Arthritis: A Case Report.

This case report describes a case of isolated adrenocorticotropic hormone (ACTH) deficiency that presented with arthritis. Initial investigations, including blood tests, imaging, and musculoskeletal ultrasonography, did not confirm to any specific connective tissue disease, making it initially difficult to identify the cause of the arthritis. Subsequent adrenal crisis led to the diagnosis of isolated ACTH deficiency through comprehensive endocrine evaluation. The patient's musculoskeletal symptoms were resolved following corticosteroid replacement therapy together with generalized symptoms. This report highlights isolated ACTH deficiency as a rare but one of the causes of polyarticular joint pain and underscores the importance of considering endocrine disorders in the differential diagnosis of unexplained arthritis, particularly when accompanied by systemic symptoms.

The lymphocyte-specific protein tyrosine kinase-specific inhibitor A-770041 attenuates lung fibrosis via the suppression of TGF-ß production in regulatory T-cells.

BACKGROUND: Lymphocyte-specific protein tyrosine kinase (Lck) is a member of the Src family of tyrosine kinases. The significance of Lck inhibition in lung fibrosis has not yet been fully elucidated, even though lung fibrosis is commonly preceded by inflammation caused by infiltration of T-cells expressing Lck. In this study, we examined the effect of Lck inhibition in an experimental mouse model of lung fibrosis. We also evaluated the effect of Lck inhibition on the expression of TGF-ß1, an inhibitory cytokine regulating the immune function, in regulatory T-cells (Tregs). METHODS: Lung fibrosis was induced in mice by intratracheal administration of bleomycin. A-770041, a Lck-specific inhibitor, was administrated daily by gavage. Tregs were isolated from the lung using a CD4+CD25+ Regulatory T-cell Isolation Kit. The expression of Tgfb on Tregs was examined by flow cytometry and quantitative polymerase chain reaction. The concentration of TGF-ß in bronchoalveolar lavage fluid (BALF) and cell culture supernatant from Tregs was quantified by an enzyme-linked immunosorbent assay. RESULTS: A-770041 inhibited the phosphorylation of Lck in murine lymphocytes to the same degree as nintedanib. A-770041 attenuated lung fibrosis in bleomycin-treated mice and reduced the concentration of TGF-ß in BALF. A flow-cytometry analysis showed that A-770041 reduced the number of Tregs producing TGF-ß1 in the lung. In isolated Tregs, Lck inhibition by A-770041 decreased the Tgfb mRNA level as well as the concentration of TGF-ß in the supernatant. CONCLUSIONS: These results suggest that Lck inhibition attenuated lung fibrosis by suppressing TGF-ß production in Tregs and support the role of Tregs in the pathogenesis of lung fibrosis.

Lenvatinib-induced Interstitial Pneumonia in a Patient with Hepatocellular Carcinoma.

Lenvatinib is a multi-targeted tyrosine kinase inhibitor available for the treatment of unresectable hepatocellular carcinoma (HCC). We herein report an 84-year-old-man with interstitial pneumonia caused by lenvatinib. Four months after the start of lenvatinib administration for HCC, chest computed tomography revealed bilateral ground-glass opacity. However, he continued to take lenvatinib for four more months until he complained of dyspnea on exertion. This is a case of lenvatinib-induced interstitial pneumonia that progressed relatively slowly with a long asymptomatic period despite the appearance of pneumonia on image findings.

Neuropsychiatric systemic lupus erythematosus with cerebellar vasculitis and obstructive hydrocephalus requiring decompressive craniectomy.

A 36-year-old woman who had been diagnosed with systemic lupus erythematosus (SLE) was admitted to our hospital due to increasing disease SLE activity. Despite the intensification of immunosuppressive treatment, headache newly developed and worsened. Magnetic resonance imaging (MRI) revealed spreading of a high-intensity area along the sulci of the bilateral cerebellar hemispheres. She was diagnosed with neuropsychiatric SLE and methylprednisolone (mPSL) pulse therapy was started. However, consciousness disorder due to cerebellar oedema with obstructive hydrocephalus appeared and required decompressive craniectomy. The histological findings of the biopsy specimens from cerebellar vermis were compatible with features of vasculitis. She was successfully treated adding intravenous cyclophosphamide therapy.

Development of improved method to identify and analyze lung fibrocytes with flow cytometry in a reporter mouse strain.

INTRODUCTION: Fibrocytes are emerging myeloid-derived circulating cells that can migrate into damaged tissues and usually contribute to their repair. Key features of fibrocytes include the expression myeloid markers, production of extracellular matrix proteins, and secretion of various humoral factors that activate resident fibroblasts; they also have the potential to differentiate into fibroblasts. However, no specific surface markers have been identified to identify fibrocytes in vivo. One reason could be that the method used to detect fibrocytes requires intracellular collagen staining. METHODS: In the present study, to establish an improved method for the detection of lung fibrocytes and to analyze viable fibrocytes, we used collagen I(α)2-green fluorescent protein (Col-GFP) reporter mice, which had undergone the intratracheal instillation of bleomycin (BLM). RESULTS: Using flow cytometry to gate out cells with autofluorescence, we clearly found that CD45+ GFP+  cells resided in the lungs of Col-GFP mice at a steady state and these cells increased after BLM injury, peaking at Day 14. These cells expressed not only known cell surface markers of fibrocytes, but also some novel markers, in addition to a low level of collagen I in comparison to CD45- GFP+  cells. CONCLUSION: Our findings suggest that the improved method can be a useful for the detection of pure lung fibrocytes and allows us to further analyze the characteristics of viable fibrocytes.

Distinct improvement of pulmonary function, ground-glass opacity, hypoxia and physical findings in an idiopathic pulmonary fibrosis patient after pirfenidone treatment : a case report with a review of the literature.

Background : Pirfenidone (PFD), an anti-fibrosis drug for idiopathic pulmonary fibrosis (IPF), suppresses disease progression and delays decline of forced vital capacity. However, this drug rarely makes marked improvement of pulmonary function, chest high-resolution computed tomography (HRCT) findings and hypoxia. Case presentation : A 59 year-old-man, who was a former smoker and had a history of alcoholic liver cirrhosis, developed exertional dyspnea and was referred to our hospital. HRCT showed honeycomb changes with surrounding ground-glass opacity (GGO) in a predominantly basal and subpleural distribution. He was diagnosed with IPF and the treatment with PFD was started. At 16 months after the start of treatment, the predicted forced vital capacity value markedly improved from 82.9% to 98.6%. His resting-state partial pressure of arterial oxygen while breathing room air increased from a minimum of 54.7 mmHg (at 2 months treatment) to 72.5 mmHg. The GGO observed at diagnosis disappeared in HRCT. But after 32 months of treatment, his general condition got worse gradually, and he died from chronic progression of IPF after 48 months of treatment. Conclusion : Our case suggests that a complication of chronic liver disease and the existence of GGO may be characteristics of super-responder to PFD treatment for IPF patients. J. Med. Invest. 67 : 358-361, August, 2020.

Clinical features of interstitial pneumonia associated with systemic lupus erythematosus.

BACKGROUND: Systemic lupus erythematosus (SLE) commonly affects the lungs. However, the incidence of interstitial pneumonia (IP) related to SLE was reported to be about 10%, less than in the case of other connective tissue diseases, and the mechanism via which IP is related to SLE remains to be elucidated. METHODS: We retrospectively reviewed the medical records and high-resolution computed tomography (HRCT) images of 69 SLE patients who were admitted to our hospital between January 2011 and December 2015. RESULTS: Fifty-five of the patients were female (80%), and the mean age at the onset of SLE was 42.4 years. IP developed in 20 patients (29%), 14 of whom were female (70%), and the mean age at SLE onset was 53.4 years, significantly older than those without IP (38.0 years) (p = 0.003). Half of the patients were found to have IP during the initial diagnosis of SLE. The IP pattern on the HRCT images was consistent with that of usual interstitial pneumonia (UIP) in 25% of the patients and of nonspecific interstitial pneumonia (NSIP) in 55%. One patient exhibited acute exacerbation but survived. The radiological findings revealed that the disease progressed slowly in most of the patients; however, pulmonary function was retained. No significant differences were observed in the survival rates between patients with and without IP. CONCLUSION: In SLE cases, IP primarily occurred in male and elderly patients. In addition to the NSIP pattern, the UIP pattern was evident on HRCT scans of IP-related SLE. The survival of SLE patients was unrelated to IP.

Kikuchi-Fujimoto disease associated with community acquired pneumonia showing intrathoratic lymphadenopathy without cervical lesions.

INTRODUCTION: Kikuchi-Fujimoto disease (KFD), or histiocytic necrotizing lymphadenitis, is a rare entity of unknown etiology in young adults that is typically characterized by cervical lymphadenopathy and persistent fever. The pathogenesis of KFD has been suggested to be an abnormal immune response, and infections or autoimmune diseases are considered to be involved in KFD. However, KFD associated with community acquired pneumonia (CAP) has not been reported. CASE DESCRIPTION: A 35-year-old male was admitted due to high fever, diffuse air-space consolidation in the right lung with ipsilateral pleural effusion and massive mediastinal and hilar lymphadenopathy without cervical lesions. On clinical suspicion of malignant lymphoma complicated with pneumonia, we performed a video-assisted thoracoscopic lymph node biopsy, and the diagnosis of KFD was established. Complete cure of the intrathoratic lesions was observed by administration of ß-lactam antibiotics alone without steroid therapy. DISCUSSION AND EVALUATION: Previous large case series have identified no pathogenic relationship between KFD and pneumonia. The hilar adenopathy could have caused airway compression leading to pneumonia. CONCLUSIONS: KFD should be considered in the differential diagnosis of massive mediastinal and hilar lymphadenopathy, even when there are no superficial lesions. In addition, we need to bear in mind that unexpected disorders occasionally coexist with common diseases.

Primary Gingival Tuberculosis Diagnosed Based on Genetic Identification.

A case of primary gingival tuberculosis in a 71-year-old Japanese woman is herein presented. A serous saliva culture was positive for tuberculosis, and we recognized that the origin of the tuberculosis infection was the gingiva based on the genetic identification in gingival biopsy tissue. The definitive diagnosis was facilitated by the genetic identification, a useful modern tool for diagnosing infectious diseases. The location and clinical presentation of this lesion were unusual, which underlines the importance of considering tuberculosis in the differential diagnosis of oral lesions that affect the gingiva.