Step ladder VY advancement flap for lower eyelid reconstruction after resection eyelid malignant tumors.

BACKGROUND: In oculoplastic surgery, reconstruction of a large defect after the removal of a massive malignant lower lid tumor still represents a unique challenge. We will report on this case, including a presentation of the case using step ladder V-Y advancement flap. METHODS: During November 2018 to March 2023, five patients of lower eyelid malignant tumor had wide resection with safety margin and reconstructed using step ladder V-Y advancement flap. The flap was used step ladder V-Y advancement flap. RESULTS: No complications, including ectropion deformity, occurred. This flap does not sacrifice healthy skin as seen with the cheek rotation flap, and the area of dissection is very small and can be performed in a short time. CONCLUSIONS: Step ladder V-Y advancement flap is highly useful in cases that require a reconstruction of a large defect after the removal of a massive malignant lower lid tumor from viewpoints of operating time, ease of procedure, aesthetics, and complications.

Deep palm burn treated with enzymatic debridement followed by autologous skin cell suspension: a case study.

Despite improvements in treatment methods and outcomes, burns remain one of the principal causes of mortality and morbidity worldwide. Burns involving the hands are estimated to occur in >80% of people with burns. Hand burns have also been associated with long-term social, psychological and physical consequences that can impede a patient's full reintegration to the community and decrease their overall quality of life. Clinically, when the trajectory towards complete re-epithelialisation stalls in deep burn wounds of the hand, skin grafting is indicated, but cosmetic problems often remain. A recent publication highlighted common complications for burns involving the hand such as scar disturbances (26%) and scar contractures (14%). Innovative approaches with the potential to reduce the occurrence of complicating scar disturbances and contractures are sought by healthcare providers specialising in burns. This case report describes a novel approach to wound closure using a topical concentrate of proteolytic enzymes followed by the application of an autologous skin cell suspension. This combination was effective in achieving early and complete re-epithelialisation of a deep burn of the palm of a 28-year-old male patient, while potentially affording a favourable impact on hypertrophic scarring or scar contracture.

Force-Temporal Characteristics of EEG-EMG Coherence during Isometric Contraction of Lateral Head of Gastrocnemius Muscle.

Coherence between an electroencephalogram (EEG) and an electromyogram (EMG) of the soleus (SOL) muscle during an isometric contraction is observed in the beta-band (15 to 35 Hz) regardless of the contraction force. However, the dynamics on how a variation in coherence occurs over time in the head of the gastrocnemius (GLH) muscle, which is also known to have the same role as the soleus muscle, have yet to be considered. In this study, we focused on GLH and measured an EEG and EMG taken of the GLH muscle when executing an isometric contraction through the dorsiflexion of the right ankle joint for a 1-min period. Moreover, we investigated changes in the EEG-EMG coherence based on the contraction force and elapsed time. As a result, in most subjects, the peak coherence during a weak contraction force was continuously observed in the ß-band, whereas the peak coherence during a strong contraction force was observed in the γ-band (35 to 60 Hz) for only the first 12 s. In addition, no significant coherence was observed. Therefore, it was suggested that muscle fatigue induced by a strong contraction force affects the peak coherence. Meanwhile, the inconsistencies observed between the properties of the peak coherence and SOL might be due to the differences in muscle composition.

Synthesis of Non-Natural Heteroaminopolysaccharides by α-Glucan Phosphorylase-Catalyzed Enzymatic Copolymerization: α(1→4)-Linked Glucosaminoglucans.

Thermostable α-glucan phosphorylase-catalyzed enzymatic copolymerization of α-d-glucose 1-phosphate (Glc-1-P) with its analogue monomer, α-d-glucosamine 1-phosphate (GlcN-1-P), from a maltotriose primer was performed to produce non-natural heteroaminopolysaccharides composed of Glc/GlcN units, that is, α(1→4)-linked glucosaminoglucans. The GlcN units in the products were further converted to N-acetyl-d-glucosamine (GlcNAc) units by N-acetylation. The structures of the products were evaluated by the MALDI-TOF MS, (1)H NMR, and (1)H-(1)H COSY NMR measurements, which were completely different from those of the natural glycosaminoglycans. The degrees of polymerization and Glc/GlcN compositional ratios of the products were relatively dependent on the Glc-1-P/Glc-1-P/Glc3 feed ratios. The noncrystalline natures of the present materials were supported by the X-ray diffraction measurement.

Synthesis of chitin and chitosan stereoisomers by thermostable α-glucan phosphorylase-catalyzed enzymatic polymerization of α-D-glucosamine 1-phosphate.

The relationship between two aminopolysaccharide stereoisomers, namely α-(1→4)- and ß-(1→4)-linked (N-acetyl)-D-glucosamine polymers, is of significant interest within the field of polysaccharide science, as they correspond to amino analogs of the representative abundant natural polysaccharides, viz. amylose and cellulose. While the latter glucosamine polymer is the basis of well-known natural polysaccharides, chitin and chitosan (linear polysaccharides composed of ß-(1→4)-linked N-acetyl-D-glucosamine and D-glucosamine), to the best of our knowledge, the former (α-(1→4)-linked) has not been observed in nature. For the purpose of these studies, the synthesis of such non-natural aminopolysaccharides was performed by the thermostable α-glucan phosphorylase (from Aquifex aeolicus VF5)-catalyzed enzymatic polymerization of α-D-glucosamine 1-phosphate (GlcN-1-P), via successive α-glucosaminylations, in ammonia buffer containing Mg(2+) ions, resulting in the production of the α-(1→4)-linked D-glucosamine polymers, corresponding to the structure of the chitosan stereoisomer. Subsequent N-acetylation of the products gave the aminopolysaccharides, corresponding to the chitin stereoisomer.