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The change in the conformation of poly(L-glutamic acid) from a random coil to an alpha-helix in solutions of guanidinium salts with a dodecanoylamidoalkyl group, C12A(sub m)G, is investigated. The results proved that C12A(sub m)G binds strongly to P(Glu), and that the methylene spacer between the acyl group and the guanidinium ion affects both C12A(sub m)G binding and formation of the alpha-helix in P(Glu).

Rationale: Fibroblasts are believed to be the major cells responsible for the production and maintenance of extracellular matrix. Alterations in fibroblast functional capacity, therefore, could play a role in the pathogenesis of pulmonary emphysema, which is characterized by inadequate maintenance of tissue structure.Objectives: To evaluate the hypothesis that deficient fibroblast repair characterizes cells obtained from individuals with chronic obstructive pulmonary disease (COPD) compared with control subjects.Methods: Fibroblasts were cultured from lung tissue obtained from individuals undergoing thoracotomy and were characterized in vitro.Measurements and Main Results: Fibroblasts from individuals with COPD, defined by reduced FEV(1), manifested reduced chemotaxis toward fibronectin and reduced contraction of three-dimensional collagen gels, two bioassays associated with fibroblast repair function. At least two mechanisms appear to account for these differences. Prostaglandin E (PGE), a known inhibitor of fibroblast repair functions, was produced in increased amount by fibroblasts from subjects with COPD, which also expressed increased amounts of the receptors EP2 and EP4, both of which signal through cyclic AMP. Incubation of fibroblasts with indomethacin or with the PKA inhibitor KT-5720 partially restored COPD subject fibroblast function. In addition, fibroblasts from subjects with COPD produced more transforming growth factor (TGF)-beta1, but manifested reduced response to TGF-beta1. The functional alterations in fibroblasts correlated with both lung function assessed by FEV(1) and, for the data available, with severity of emphysema assessed by Dl(CO).Conclusions: Fibroblasts from individuals with COPD have reduced capability to sustain tissue repair, which suggests that this may be one mechanism that contributes to the development of emphysema. [ABSTRACT FROM AUTHOR]

Highlights: [•] SPC augments fibroblast-mediated collagen gel contraction. [•] SPC stimulates a-smooth muscle actin expression in fibroblasts. [•] SPC activates Rho A/Rho kinase pathway. [Copyright &y& Elsevier]

A female patient developed multiple intestinal perforations at 31 and 43 years of age. Because of her family history of pneumothorax and intestinal perforation, Ehlers-Danlos syndrome (EDS) was suspected when she visited our hospital at 52 years. She was diagnosed with vascular Ehlers-Danlos syndrome (vEDS) and developed bilateral external iliac artery dissection. A CT scan at the time of admission revealed granular and infiltrative shadows in both lungs with bronchiectasis. The patient was also diagnosed with Mycobacterium avium complex (MAC) pulmonary disease, and drug susceptibility to clarithromycin was confirmed. After treatments with rifampicin, ethambutol, and clarithromycin were started, the acid-fast bacilli cultures taken from sputum were negative, and respiratory symptoms partially improved after about 1 month. vEDS is reportedly associated with lung diseases, such as pneumothorax and cystic lung lesions, but there are few reports of respiratory infections with vEDS. Moreover, there are no reports of complications associated with MAC disease. We report a case of vEDS with rare complications and suggest the possible mechanism of infection., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors.)

A 69-year-old woman was diagnosed with idiopathic interstitial pneumonia (IIP). The patient underwent a combination therapy of steroid therapy and intravenous cyclophosphamide, long-term oxygen therapy, and the initiation of Nintedanib. However, there was no improvement in IIP, and as a result, the activities of daily living also declined. As one of the various examinations conducted, the results of the right heart catheterization diagnosed the patient with mild pulmonary hypertension, and Macitentan therapy was initiated. The subsequent clinical course appeared to show an improvement in Idiopathic Interstitial Pneumonia (IIP) by adding Macitentan therapy to Nintedanib therapy., Competing Interests: No conflict of interest to declare., (© 2024 Published by Elsevier Ltd.)