Light-regulated nitric oxide release from hydrogel-forming microneedles integrated with graphene oxide for biofilm-infected-wound healing.

Nitric oxide (NO) is an antimicrobial agent that possesses tissue-regenerating ability. However, it also has a short half-life and storage difficulties as disadvantages to its application. To overcome these limitations, a new type of hydrogel-forming microneedle (HFMN) is proposed that can be fabricated by integrating polyvinyl alcohol (PVA) hydrogels (a highly biocompatible drug carrier) with S-nitrosoglutathione (GSNO, a NO releasing agent), and graphene oxide (GO) at freezing temperatures (GO-GNSO-HFMNs). Results show that GSNO-GO-HFMNs release NO gradually with increasing temperature and, more importantly, can be warmed up by mild infrared irradiation to accelerate subcutaneous release of NO from the heat-sensitive GSNO. Biofilm-infected wounds often present obstacles to drug delivery, whereas the microneedle (MN) structure disrupts the biofilm and directly releases NO into the wound. This inhibits bacterial growth and increases tissue regeneration while shortening the healing time of biofilm-infected wounds. Therefore, this type of patch can be regarded as a novel, heat-sensitive, light-regulated, NO-releasing MN patch.

A Modified Double Eyelid Plastic Surgery Method: Continuous Buried Suture Method Accompanied by Simultaneous Correction of Mild Blepharoptosis.

BACKGROUND: Double eyelid surgery with a buried suture is a popular plastic surgery procedure in Asia owing to the relatively minor scarring and quick recovery associated with it. In this article, we present a new approach involving a continuous single-loop buried suture method, which expands the operating site to the conjunctiva and the aponeurosis-Müller's muscle complex. METHODS: The medical records of 42 patients (80 eyes) who underwent double-eyelid blepharoplasty were retrospectively reviewed. We performed double-eyelid blepharoplasty with a single-knot continuous buried suture method, along with the resection of a small piece of the orbicularis oculi muscle. The formation of a double eyelid was achieved through traction of the aponeurosis-Müller's muscle complex from the medial conjunctiva and penetration of the upper eyelid. RESULTS: The majority of patients achieved the expected cosmetic effect of double eyelid formation after the procedure. In the subsequent follow-up period of 2-30 months, no complications, such as loosing or sagging of the double eyelid or granuloma formation, occurred. The mean recovery time ranged between one and 6 weeks. The pre-operative margin reflex distance (MRD1) was 2.36 ± 0.61 mm, and the post-operative MRD1 was 3.72 ± 0.63 mm, (p < 0.001). The Wilcoxon signed rank test was used for nonparametric, paired comparisons. CONCLUSIONS: We proposed a modified technique involving a continuous buried suture method to create a better cosmetic effect through the formation of a double eyelid and simultaneous correction of mild blepharoptosis. This modified procedure is simple, fast, and effective, with limited adverse effects. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these evidence-based medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Porphyrin-triarylamine conjugates: strong electronic communication between triarylamine redox centers via the porphyrin dication.

A set of porphyrin-triarylamine hybrids have been synthesized in good yield by Sonogashira palladium-catalyzed cross-coupling reactions between the zinc complex of 5,15-diethynyl-10,20-dimesitylporphyrin and the appropriate iodophenyldiarylamines. The crystal structure of porphyrin 1 shows that the dihedral angle between the acetylene-bonded benzene rings and the porphyrin macrocycle is 20.0 degrees. Such a structural characteristic enables effective electronic perturbations within the molecule. The electronic spectra are red-shifted and display a broad Soret band and an intense Q band relative to those of meso-substituted tetraarylporphyrins. These conjugates display four oxidations and one reduction. All the electrochemical reactions involve one-electron transfer. The first and second oxidations are reversible and can be assigned to the porphyrin-centered reactions. The third and fourth ones, separated by about 270 mV, correspond to the triarylamine units. The comproportionation constant (Kc) is calculated to be 3.67x10(4). The electron coupling between the triarylamine moieties, at a separation of >23 A, is remarkably strong. The electrochemical results and the absorption spectra show that the electronic characteristics of these porphyrins can be significantly modulated by the triarylamine substituents via the conjugated carbon-carbon triple bond. Variations of the substituents on the triarylamines can fine-tune the electronic properties of these molecules.