Fmoc-PEG Coated Single-Wall Carbon Nanotube Carriers by Non-covalent Functionalization: An Experimental and Molecular Dynamics Study.

Due to their structural characteristics at the nanoscale level, single-walled carbon nanotubes (SWNTs), hold great promise for applications in biomedicine such as drug delivery systems. Herein, a novel single-walled carbon nanotube (SWNT)-based drug delivery system was developed by conjugation of various Fmoc-amino acid bearing polyethylene glycol (PEG) chains (Mw = 2,000, 5,000, and 12,000). In the first step, full-atom molecular dynamics simulations (MD) were performed to identify the most suitable Fmoc-amino acid for an effective surface coating of SWNT. Fmoc-glycine, Fmoc-tryptophan, and Fmoc-cysteine were selected to attach to the PEG polymer. Here, Fmoc-cysteine and -tryptophan had better average interaction energies with SWNT with a high number of aromatic groups, while Fmoc-glycine provided a non-aromatic control. In the experimental studies, non-covalent modification of SWNTs was achieved by Fmoc-amino acid-bearing PEG chains. The remarkably high amount of Fmoc-glycine-PEG, Fmoc-tryptophan-PEG, and Fmoc-cysteine-PEG complexes adsorbed onto the SWNT surface, as was assessed via thermogravimetric and UV-vis spectroscopy analyses. Furthermore, Fmoc-cysteine-PEG5000 and Fmoc-cysteine-PEG12000 complexes displayed longer suspension time in deionized water, up to 1 and 5 week, respectively, underlying the ability of these surfactants to effectively disperse SWNTs in an aqueous environment. In vitro cell viability assays on human dermal fibroblast cells also showed the low cytotoxicity of these two samples, even at high concentrations. In conclusion, synthesized nanocarriers have a great potential for drug delivery systems, with high loading capacity, and excellent complex stability in water critical for biocompatibility.

Infective endocarditis in two patients with pemphigus vulgaris under multiagent immunosuppressive drug therapy: A rare entity to remember in the differential diagnosis of fever of unknown origin.

Pemphigus vulgaris (PV) is an autoimmune blistering skin disease that may require multiagent immunosuppressive drug therapies in severe cases. In addition to the well-established corticosteroid sparing agents azathioprine, mycophenolate mofetil, and methotrexate, rituximab is being increasingly used alone or in combination in the management of PV. Due to the chronic course of the disease, the cumulative effects of these therapy agents over long follow-up periods may result in various adverse reactions, including bacterial and viral infections. Infective endocarditis (IE) is one of the rarest complications of PV treatment with only a few reported cases. In the present study, the present authors discuss two PV patients without prior histories of cardiovascular disease, complicated with native aortic valve IE, which led to death in one of the patients. Because determining the origin of fever is difficult in patients under immunosuppressive therapy, it is particularly challenging to diagnose IE coupled with a fever of unknown origin. Therefore, dermatologists must be vigilant for the dermatological signs of IE and use a multidisciplinary approach to the differential diagnosis of fever of unknown origin.

Polyethylene glycol as marker for nitrofurazone allergy: 20 years of experience from Turkey.

BACKGROUND: Polyethylene glycols (PEGs) and propylene glycol (PG) are used as vehicles in various medicinal and cosmetic products. They are potential contact sensitizers, including low molecular weight PEGs in nitrofurazone preparations that are still widely used in Turkey. OBJECTIVES: To investigate the prevalence of allergic contact dermatitis caused by PEG and PG in a relatively large group of patients in Turkey. METHODS: In this retrospective, cross-sectional, single-centre study, 836 patients patch tested with PEG and PG between 1996 and 2015 were reviewed. RESULTS: Thirty-five patients (4.2%) showed positive patch test reactions to PEG, and 7 (0.8%) showed positive patch test reactions to PG, partly as late positive reactions with PEG. PEG sensitivity was almost exclusively related to nitrofurazone allergy. Patch test reactions to PG were currently relevant mainly with regard to the use of minoxidil, and antiherpetic or corticosteroid creams. Ten patients (25%) had concomitant contact allergies to various topical drugs containing mainly PEGs. CONCLUSIONS: PEG sensitivity seems to be a marker for contact allergy to topical nitrofurazone in Turkey. Nitrofurazone allergy appears to favour concomitant sensitization to PEG. We would suggest the inclusion of PEG in an extended baseline patch test series in Turkey. Late patch test readings are important to diagnose delayed positive reactions to PEG.

Polycyclic annular presentation of pemphigus vulgaris with an eosinophil predominance in two pregnant patients.

Pemphigus during pregnancy has a more complicated course owing to the limitations in treatment options and alterations in the severity and presentation of the clinical features. We would like to present two pemphigus vulgaris (PV) cases associated with pregnancy with an unusual clinical appearance exhibiting polycyclic, annular, vesiculobullous plaques with marked eosinophil infiltration in histopathology. To the best of our knowledge pregnancy-associated pemphigus cases with this particular clinical presentation have not been reported in the literature. Changes in the immunologic and hormonal state during pregnancy may play a role in altering the classic clinical presentation and treatment response of PV.

Pigment Loss in Patients with Large Congenital Melanocytic Nevi: Various Clinical Presentations Documented in a Large Series.

BACKGROUND/OBJECTIVES: The association between vitiligo and congenital melanocytic nevi remains incompletely understood. The objective of this study was to investigate the frequency of depigmentation, including vitiligo, in patients with a large congenital melanocytic nevus (LCMN), which is a rare melanocytic tumor variant. METHODS: We retrospectively reviewed the files of 92 patients with an LCMN, including photographic documentation regarding the presence of pigment loss on the nevus mass, around the nevus, around the satellites, and elsewhere on the body. RESULTS: Depigmentation was observed in 8 (8.7%) of 92 patients with an LCMN. Depigmented areas within the main nevus mass were observed in six patients, and adjacent or remote vitiligo was observed in four patients. One patient also demonstrated halo depigmentation around some satellite nevi. CONCLUSION: The coexistence of an LCMN with vitiligo does not appear to be rare and may occur with a spectrum of clinical presentations.