Search

Aiming to produce high-quality bio-based 3D printed products, in this work, coconut fibers were chemical modified using caprolactone. Fourier-transform infrared spectroscopy (FTIR) and nuclear magnetic reasonance (NMR) confirmed the grafting of the hydroxyl groups present on the surface of the fibers with caprolactone units. Furthermore, from contact angle (CA) analyses, the higher hydrophobicity of fibers after chemical treatment was confirmed, which improved its affinity with PP. The enhanced filler/matrix compatibility was reflected on the mechanical performance and processability of the ensuing composites. The modified fibers derived composites showed higher stiffness and higher melting flow index (MFI), when compared to the untreated counterparts. The composites were used to produce 3D printed specimens. Smother filaments were obtained using modified fibers, which confirms the better compatibility of fibers/PP. The surface of the 3D printed composite specimen produced using treated fibers, presented smooth surface, similar to the PP. This observation highlights the enhancement of the 3D printing quality due to the chemical modification of fibers.

Background: Acne fulminans is a rare and exuberant variant of acne, mainly affecting young males with a previous history of acne vulgaris. It is a systemic disease of unknown etiology characterized by necrotizing acne associated with constitutional symptoms and laboratory abnormalities.Case report: Fourteen-year-old male adolescent with no previous history of acne, admitted to Paediatric Department of Hospital S. João - Porto for acne fulminans. Three weeks ago, he had consulted a Dermatologist due to the appearance of painful papular and pustular lesions on the face and anterior chest, along with low-grade fever. He was treated with amoxicillin/clavulanic acid, isotretinoin and prednisolone, with no improvement. Complementary exams showed leukocytosis with neutrophilia and elevated C-reactive protein and transaminases. In the dermatological exam, exuberant and exudative ulcerated and crusted lesions were observed localized on the trunk and, with less intensity, on the face and neck. Systemic prednisolone in higher doses, isotretinoin and topical treatment with polyurethane dressings were instituted, with clinical improvement and gradual involution of skin lesions. The therapy with isotretinoin was maintained for up to 4 months and the therapy with systemic glucocorticoid was maintained for 2 weeks and then progressively tapered.Comments: The authors describe a clinical case of acne fulminans in a male adolescent, with exuberant dermatological lesions and good therapeutic response to systemic corticoid, isotretinoin and topical treatment. Early diagnosis of acne fulminans and appropriate therapeutic intervention are essential for effective disease control to avoid deforming residual scars and to minimize the risk of recurrence.