Nanotherapeutic approach to treat diabetic foot ulcers using tissue-engineered nanofiber skin substitutes: A review

Background and aimsDiabetes mellitus (DM) is a chronic metabolic disease associated with long-term multisystem complications, among which nonhealing diabetic foot ulcers (DFUs) are recognized as major cause of morbidity and mortality. Treating DFUs with surgical procedures such as synthetic or biological skin grafts or skin substitutes has several limitations, where none of the currently available skin substitutes is ideal.MethodsOVID/Medline and PubMed databases were searched using the Medical Subject Heading (MeSH) or Title/Abstract words (“diabetic foot ulcers”, “skin substitutes”, and “nanofibers”), to identify published research studies on DFUs and nanofibers.ResultsElectrospinning nanotechnology is being used in the biomedical field to produce polymeric nanofibers impregnated with drugs for wound healing, burns and diabetic ulcers. Those nanofibers also enable seeding of cells into them and culturing them in vitro to synthesize tissue-like structures. Knowing the advantages of generating patient-specific induced pluripotent stem cells (iPSCs) and organoids in three-dimension (3D), including skin organoids, it is worth mingling these technologies to develop tissue-engineered biological skin substitutes.ConclusionNanofiber-skin substitutes hold promise for treatment of patients suffering from DFUs and inspire novel strategies that could be applied to other organ systems as well, introducing a new era of “regenerative and personalized medicine”.     

皮肤鳞状细胞癌诊疗专家共识（2021）

【摘要】 皮肤鳞状细胞癌是非黑素瘤皮肤癌中最常见的肿瘤之一。近年来随着对其发病机制研究的深入以及诊断技术、Mohs显微描记手术、靶向治疗、免疫治疗的发展，皮肤鳞状细胞癌的诊疗取得了较大进展。该共识在国内外近期文献及诊疗指南的基础上，结合我国的诊疗现状，重点阐述皮肤鳞状细胞癌的临床表现及分型、病理活检及报告规范、风险等级评估、分级分期以及规范化治疗等，为临床医生的诊疗工作提供参考依据。     

The effect of patient ethnicity on the accuracy of peripheral pulse oximetry in patients with COVID-19 pneumonitis: a single-centre,retrospective analysis

Pulse oximetry is used widely to titrate oxygen therapy and for triage in patients who are critically ill. However, there are concerns regarding the accuracy of pulse oximetry in patients with COVID-19 pneumonitis and in patients who have a greater degree of skin pigmentation. We aimed to determine the impact of patient ethnicity on the accuracy of peripheral pulse oximetry in patients who were critically ill with COVID-19 pneumonitis by conducting a retrospective observational study comparing paired measurements of arterial oxygen saturation measured by co-oximetry on arterial blood gas analysis (SaO₂) and the corresponding peripheral oxygenation saturation measured by pulse oximetry (S_pO₂). Bias was calculated as the mean difference between SaO₂ and S_pO₂ measurements and limits of agreement were calculated as bias ±1.96 SD. Data from 194 patients (135 White ethnic origin, 34 Asian ethnic origin, 19 Black ethnic origin and 6 other ethnic origin) were analysed consisting of 6216 paired SaO₂ and S_pO₂ measurements. Bias (limits of agreement) between SaO₂ and S_pO₂ measurements was 0.05% (−2.21–2.30). Patient ethnicity did not alter this to a clinically significant degree: 0.28% (1.79–2.35), −0.33% (−2.47–2.35) and −0.75% (−3.47–1.97) for patients of White, Asian and Black ethnic origin, respectively. In patients with COVID-19 pneumonitis, S_pO₂ measurements showed a level of agreement with SaO₂ values that was in line with previous work, and this was not affected by patient ethnicity.     

Caveolin-1 in skin aging – From innocent bystander to major contributor

Caveolin-1 (Cav-1) appears to be both a pathophysiological contributor and a target in different inflammatory and hyperproliferative skin conditions as well as in skin aging. Skin fibroblasts demonstrate an up-regulation of Cav-1 expression both in chronological and UV-induced aging, and such an up-regulation was observed both in vitro and in vivo. Typical alterations in aging skin involve a reduction of the dermis thickness, a significant expansion of the dermal white adipose tissue as well as modifications of the content and distribution of hyaluronan, impairment of autophagic flux, a reduction of collagen expression and an increase in tissue inflammation. All of these phenomena can be connected with changes in Cav-1 expression in the aging skin. Modified expression of Cav-1 can also significantly influence the mechanical properties of individual skin layers, thus changing the total mechanical stability of the layered composite skin/WAT, leading to typical structural modifications of the skin surface in the aging skin. Selective reduction of Cav-1 expression has the potential to exert anti-aging effects on the skin.     

Comparative Measurement of Biophysical Parameters in Consideration of Skin Graft Donor Site for Nasal Defects

BackgroundIn planning a skin graft, the texture, color, and size of the recipient and donor site tissues should be considered.ObjectiveWe determined the optimal donor sites for nasal full-thickness skin grafting based on biophysical parameters.MethodsThirty women over the age of 60 were selected for this study. Four recipient sites (nasal root, dorsum, tip, ala) and three donor sites (preauricle, postauricle, forehead) were considered. Biophysical parameters such as transepidermal water loss (TEWL), capacitance, sebum output, erythema/melanin value, and skin replica technique were tested.ResultsThe nasal root was correlated with the forehead in terms of TEWL and sebum output. The nasal dorsum was correlated with the preauricle in terms of TEWL, erythema/melanin value, and skin replica measurements. The nasal tip was correlated with the preauricle in terms of TEWL, sebum output, erythema/melanin value, and skin replica measurements. The ala was correlated with the forehead in terms of TEWL and skin replica measurements.ConclusionThe preauricule is the optimal donor site for resurfacing of the nasal dorsum and tip. The forehead is a good donor site for alar defects. For resurfacing of the nasal root, the forehead and postauricle are good choices.     

三步序贯法治疗四肢皮肤软组织缺损合并骨或肌腱外露创面

目的:探讨采用改良VSD技术、皮耐克覆盖、自体皮移植三步序贯法治疗拒绝皮瓣修复的四肢皮肤软组织缺损合并骨或肌腱外露创面的临床疗效。方法:2013年1月至2015年6月,采用三步序贯法治疗18例四肢创伤后皮肤软组织缺损合并骨或肌腱外露创面患者,其中男13例,女5例;年龄23～72岁,平均34.6岁;受伤至手术时间1.5～5.0 h,平均2.5 h。皮肤软组织缺损面积4.2 cm×3.1 cm～7.4 cm×5.2 cm。评估创面恢复情况及取皮创口恢复情况综合评价治疗效果。结果:术后18例患者获得随访,时间5～16个月,平均7.6个月。所有创面深部骨肌腱组织被有效覆盖,人工真皮成活,愈合创面质地韧、外形可;创面移植皮片成活,未见明显瘢痕组织生成,外观平整,皮肤颜色略深于正常皮肤,整体效果满意。结论:采用三步序贯法治疗拒绝皮瓣修复的四肢皮肤软组织缺损合并骨或肌腱外露创面疗效良好,具有操作简单、手术风险及创伤小等优点。     

Clinical Characteristics and Genetic Variations in Early-Onset Atopic Dermatitis Patients

BackgroundHereditary factors contribute to atopic dermatitis (AD) development. We developed the reverse blot hybridization assay (REBA) kit to simultaneously detect variations in skin barrier- and immune response-related genes prevalent in Korean AD patients.ObjectiveTo identify genetic variations and clinical characteristics that could predict early AD development.MethodsWe compared AD-related genetic variations between early-onset AD subjects and non-AD controls, and clinical characteristics and genetic variations between early- and late-onset AD subjects. We compared 28 early-onset AD subjects and 57 non-AD controls from a birth cohort and 108 early- (age ≤3 years) and 90 late-onset AD subjects and 189 non-AD controls from a university hospital. Genetic variations were detected via REBA.ResultsThere were no differences in AD-related genetic variation between early-onset AD subjects and non-AD controls in the birth cohort. When the birth cohort and hospital populations were combined, early-onset AD subjects and non-AD controls showed different frequencies of genetic variations of KLK7, SPINK5 1156, DEFB1, IL5RA, IL12RB1a, and IL12RB1b. No differences in the frequency of genetic variations were observed between early- and late-onset AD subjects. Immunoglobulin E positivity for house dust mites was prevalent in late-onset AD subjects. A family history of atopic diseases was associated with early-onset AD.ConclusionNo AD-related genetic variations could predict early AD development in Koreans, even though neonates with a family history of atopic diseases are likely to develop AD at ≤3 years of age. Environmental exposure may be more important than genetic variation in determining the onset age of AD.