Anti-Microbial Activities of Mussel-Derived Recombinant Proteins against Gram-Negative Bacteria

Many anti-microbial peptides (AMPs) and pro-apoptotic peptides are considered as novel anti-microbial agents, distinguished by their different characteristics. Nevertheless, AMPs exhibit certain limitations, including poor stability and potential toxicity, which hinder their suitability for applications in pharmaceutics and medical devices. In this study, we used recombinant mussel adhesive protein (MAP) as a robust scaffold to overcome these limitations associated with AMPs. Mussel adhesive protein fused with functional peptides (MAP-FPs) was used to evaluate anti-microbial activities, minimal inhibitory concentration (MIC), and time-kill kinetics (TKK) assays against six of bacteria strains. MAP and MAP-FPs were proved to have an anti-microbial effect with MIC of 4 or 8 µM against only Gram-negative bacteria strains. All tested MAP-FPs killed four different Gram-negative bacteria strains within 180 min. Especially, MAP-FP-2 and -5 killed three Gram-negative bacteria strain, including E. coli, S. typhimurium, and K. pneumoniae, within 10 min. A cytotoxicity study using Vero and HEK293T cells indicated the safety of MAP and MAP-FP-2 and -3. Thermal stability of MAP-FP-2 was also validated by HPLC analysis at an accelerated condition for 4 weeks. This study identified that MAP-FPs have novel anti-microbial activity, inhibiting the growth and rapidly killing Gram-negative bacteria strains with high thermal stability and safety.

Mixed connective tissue disease associated with skin defects of livedoid vasculitis

A 21-year-old woman who had a 2-year history of mixed connective tissue disease (MCTD) developed rapidly evolving ulcers consistent with livedoid vasculitis (LV) in all distal extremities. She presented clinically with Raynaud's phenomenon, polyarthritis and swollen hands; serologically with high titres of ANA and anti-nRNP; and immunogenetically with HLA-DR4 and HLA-DR53. Although there was initial success in treatment except for the skin defects over the ankles, the patient died from disseminated intravascular coagulation. We suggest that LV may be a poor prognostic manifestation in MCTD.

Secondary renal amyloidosis in adult onset Still's disease: case report and review of the literature

We report a 25-year-old Korean woman with Adult onset Still's disease (AOSD) presented with renal amyloidosis, which had developed four years after disease onset. We successfully treated her with prednisolone, colchicine and cyclophosphamide. A review of the literature uncovered about 10 cases, most of which were treated by various regimens that resulted in poor outcomes. Renal amyloidosis should be suspected in patients with AOSD who have unexplained proteinuria. Although the mechanism of renal amyloid deposition is not well known, earlier histopathologic diagnosis and choice of regimen may affect prognosis.

Giant-cell interstitial pneumonia in a gas station worker

Giant-cell interstitial Pneumonia (GIP) is a very uncommon respiratory disease. The majority of cases of GIP are caused by exposure to cobalt, tungsten and other hard metals. In this report, we describe GIP in a patient who worked in gas station and dealt in propane gas vessels. He presented with clinical features of chronic interstitial lung disease and underwent an open lung biopsy that showed DIP-like reaction with large numbers of intra-alveolar macrophages and numerous large, multinucleated histiocytes which were admixed with the macrophages. Analysis of lung tissue for hard metals was done. Cobalt was the main component of detected hard metals. Corticosteroid therapy was started and he recovered fully.