内源性大麻素系统与炎症性皮肤病

内源性大麻素系统包括内源性大麻素受体和内源性大麻素以及一系列参与内源性大麻素系统生物合成和代谢的酶类以及膜转运受体.近年来,在角质形成细胞、皮肤成纤维细胞、皮脂腺细胞等多种皮肤细胞中发现了具有生物学效应的内源性大麻素系统.越来越多的研究发现,内源性大麻素系统参与正常皮肤生理生化活动和炎症反应,并在多种炎症性皮肤病中起作用.目前内源性大麻素系统的临床应用尚不成熟,但内源性大麻素系统的研究为临床炎症性皮肤病的治疗提供了新视角和新策略.     

大麻素受体与皮肤肿瘤

大麻素受体(CB)为G蛋白耦联受体,具有抗炎、抗增殖、抗肿瘤作用.近年来越来越多的证据表明CB与皮肤肿瘤的发生发展密切相关,CB的激活抑制皮肤肿瘤的生长.CB可作为皮肤肿瘤化疗方案新的方向,并有可能作为皮肤恶性肿瘤的预后指标,也提示了大麻素受体激活剂可能作为抗皮肤肿瘤新的治疗方法.     

大麻素2型受体在寻常性银屑病皮损组织中的表达

目的 探讨大麻素2型受体在寻常性银屑病皮损组织中的表达及其意义。 方法 实时荧光定量聚合酶链反应（RT-PCR）、免疫组化技术检测20例寻常性银屑病患者皮损组织及皮损周围组织、10例非银屑病患者的正常皮肤组织中大麻素2型受体在mRNA和蛋白不同水平的表达情况。 结果 寻常性银屑病皮损组织、皮损周围组织及正常皮肤中均有大麻素2型受体mRNA表达,寻常性银屑病组表达明显高于皮损周围组及正常对照组（P < 0.05）;三组皮损组织均有大麻素2型受体蛋白表达,且寻常性银屑病组表达明显高于皮损周围组、正常对照组,差异有统计学意义（P < 0.05）。 结论 寻常性银屑病皮损组织中大麻素2型受体在基因及蛋白水平表达均升高,提示大麻素2型受体可能与寻常性银屑病的发生发展有关联。     

瘙痒介质及其受体的研究进展

瘙痒的产生是一个复杂的多因素作用的结果,其具体机制尚不完全清楚.研究已证实,瘙痒具有特异的神经传导通路,多种内源性物质与瘙痒的发病密切相关.近年来的研究表明,组胺4型受体、蛋白酶活化受体-2、白介素-31受体、神经激肽受体-1在皮肤无髓C神经纤维的表达可能介导瘙痒的发生,而神经营养素和神经生长因子及其受体则可能作为一种瘙痒敏感剂,促进瘙痒的形成与发展.这些化学介质及其受体在瘙痒发生的病理生理机制中并不是孤立地起作用,而是与神经细胞、免疫细胞及皮肤细胞紧密联系.     

大麻素2型受体在银屑病分子免疫机制中的作用研究进展

银屑病是一种以鳞屑性红斑为主要临床表现的慢性、炎症性皮肤病。有研究表明银屑病皮损表皮中大麻素2型受体表达量明显增加,大麻素2型受体可参与细胞的增殖与分化、免疫调节以及肿瘤的发生发展等病理生理过程。在角质形成细胞中大麻素2型受体激活后可能通过Akt信号通路来抑制细胞的增殖,并且抑制炎症细胞分泌细胞因子,如血管内皮生长因子、基质金属蛋白酶、IL-8、IL-17等。本文就大麻素2型受体在银屑病分子免疫机制中的作用研究作一综述。     

黑素细胞黑皮素-1受体

黑素细胞黑皮素 - 1受体在黑素的生成和调控方面起重要的作用 ,黑皮素 - 1受体功能的改变和基因突变与色素性皮肤病和皮肤肿瘤密切相关。在人皮肤中 ,几乎所有类型细胞均表达黑皮素 - 1受体 ,这预示黑皮素 - 1受体在皮肤病的发生和治疗上都具有一定的作用。现就黑素细胞黑皮素 - 1受体的配体、功能及其基因突变与皮肤病关系的研究进展作一介绍     

内源性大麻素(endocannabinoids)调节源于人类外分泌汗腺表皮细胞的生长和存活

有研究证据显示,内源性大麻素系统(endocannabinoid system,ECS)对皮肤稳态的控制具有重要作用.内源性大麻素,如安南得迈(N-花生四烯基乙醇胺,AEA)和2-花生四烯甘油(2-AG),目前参与这些脂质介质的合成及代谢的酶类、以及大麻素受体(cannabinoid receptors,CB)均在各种皮肤细胞群中被识别.不仅如此,皮肤ECS可调节皮肤细胞生长和分化之间的平衡.换言之,AEA可抑制培养的人表皮角质形成细胞的分化,也有关于AEA抑制这些细胞的生长和诱导其凋亡的报道.同样,还报道了局部产生的AEA抑制体外毛干的延伸和诱导凋亡,使毛发提前进入退行期.另外,培养源于人类皮脂腺的皮脂细胞产生的AEA和2-AG使脂质的生成量增加,并诱导细胞凋亡.尽管有报道显示,CB1和CB2在人类外分泌汗腺的表皮细胞上均存在原位表达,但仍缺乏关于内源性大麻素对哺乳动物皮肤最小附属器生物学调节作用的有效资料.因此,该研究旨在明确被广泛研究的AEA和2-AG对人类外分泌汗腺细胞生长和存活的影响.     

脂联素与免疫性皮肤病

脂联素是一种主要由脂肪细胞分泌的内源性生物活性蛋白质,以三聚体、六聚体和高分子量多聚体3种不同的形式存在于外周血中.脂联素与其受体结合后,通过激活下游的信号通路,发挥调控新陈代谢、调节免疫平衡、抑制细胞增殖和炎症反应、维持血管稳态等重要作用,而其免疫调节作用日益成为研究的焦点.近年来研究表明,脂联素积极参与免疫性皮肤病的进程,随着对脂联素免疫调节作用研究的不断深入,其与免疫性皮肤病的关系亦取得了较大进展.拟为今后免疫性皮肤病的临床治疗及用药提供新的方法和思路.概述脂联素与银屑病、系统性红斑狼疮、硬皮病及干燥综合征等免疫性皮肤病的关系.     

黑素细胞黑皮素—1受体

黑素细胞黑皮素－1受体在黑素的生成和调控方面起重要的作用，黑皮素－1受体功能的改变和基因突变与色素性皮肤病和皮肤肿瘤密切相关。在人皮肤中，几科所有类型细胞均表达黑皮素－1受体，这预示黑皮素－1受体在皮肤病的发生和治疗上都具有一定的作用。现就黑素细胞黑皮素－1受体的配体、功能及其基因突变与皮肤病关系的研究进展作一介绍。     

皮肤中维A酸受体与皮肤病

维A酸可治疗多种皮肤病 ,其作用主要是通过维A酸受体介导的。本文综述维A酸受体在皮肤中的分布特点及其调控角质蛋白合成的机制 ;受体选择性维A酸药物治疗皮肤病的优越性 ;维A酸受体与另一种核受体维生素D3受体的关系 ;维A酸受体与某些皮肤病发生、发展的关系。研究维A酸受体将有助于认识皮肤病的发生、发展过程 ,为维A酸药物的科学应用提供理论依据。     

New fillers for the new man

ABSTRACT:  Two new collagen-based lidocaine-containing dermal fillers, ArteSense™/ArteFill™ (Artes Medical, San Diego, CA) and Evolence® (Colbar LifeScience Ltd., Herzliya, Israel), have proved to be of particular interest to men, many of whom seek a long-lasting or permanent correction. ArteFill™ has been available in the United States since 2006, and it is expected that Evolence® will reach the American market in 2008. The properties of the two products will be described, and experience based on the administration of many hundreds of syringes of both products by a Canadian dermatologist will be detailed here, with tips and precautions to optimize patient outcomes.     

Outcomes and adverse effects of ablative vs nonablative lasers for skin resurfacing: A systematic review of 1093 patients

It is generally believed that ablative laser therapies result in prolonged healing and greater adverse events when compared with nonablative lasers for skin resurfacing. To evaluate the efficacy of ablative laser use for skin resurfacing and adverse events as a consequence of treatment in comparison to other modalities, a PRISMA‐compliant systematic review (Systematic Review Registration Number: 204016) of twelve electronic databases was conducted for the terms “ablative laser” and “skin resurfacing” from March 2002 until July 2020. Studies included meta‐analyses, randomized control trials, cohort studies, and case reports to facilitate evaluation of the data. All articles were evaluated for bias. The search strategy produced 34 studies. Of 1093 patients included in the studies of interest, adverse events were reported in a total of 106 patients (9.7%). Higher rates of adverse events were described in nonablative therapies (12.2% ± 2.19%, 31 events) when compared with ablative therapy (8.28% ± 2.46%, 81 events). 147 patients (13.4%) reported no side effects, 68 (6.22%) reported expected, transient self‐resolving events, and five (0.046%) presented with hypertrophic scarring. Excluding transient events, ablative lasers had fewer complications overall when compared with nonablative lasers (2.56% ± 2.19% vs 7.48% ± 3.29%). This systematic review suggests ablative laser use for skin resurfacing is a safe and effective modality to treat a range of pathologies from photodamage and acne scars to hidradenitis suppurativa and posttraumatic scarring from basal cell carcinoma excision. Further studies are needed, but these results suggest that ablative lasers are a superior, safe, and effective modality to treat damaged skin.     

Genetic alterations in RAS‐regulated pathway in acral lentiginous melanoma

Studies integrating clinicopathological and genetic features have revealed distinct patterns of genomic aberrations in Melanoma. Distributions of BRAF or NRAS mutations and gains of several oncogenes differ among melanoma subgroups, while 9p21 deletions are found in all melanoma subtypes. In the study, status of genes involved in cell cycle progression and apoptosis was evaluated in a panel of 17 frozen primary acral melanomas. NRAS mutations were found in 17% of the tumors. In contrast, BRAF mutations were not found. Gains of AURKA gene (20q13.3) were detected in 37.5% of samples, gains of CCND1 gene (11q13) or TERT gene (5p15.33) in 31.2% and gains of NRAS gene (1p13.2) in 25%. Alterations in 9p21 were identified in 69% of tumors. Gains of 11q13 and 20q13 were mutually exclusive, and 1p13.2 gain was associated with 5p15.33. Our findings showed that alterations in RAS‐related pathways are present in 87.5% of acral lentiginous melanomas.     

Self‐resolving superficial primary cutaneous mucormycosis in a 7‐week‐old infant

A 7‐week‐old girl, born at 30 weeks' gestational age, presented to clinic for evaluation of a crop of vesicular lesions that were noted after removal of a bandage that had been in place for 4 days. A punch biopsy of the lesion revealed fungal elements that were later identified as Rhizopus spp. The lesion began to self‐resolve, and no further treatment was needed, with full resolution of the lesion by 1 month after presentation. Clinicians should be aware of the variable presentations of mucormycosis and consider fungal infection in the differential diagnosis when evaluating vulnerable patients with skin eruptions.     

Multiple New-Onset Subcutaneous Nodules of the Upper Extremity Digits: Giant Cell Tumor of Tendon Sheath and Lipoma

A black woman with the concurrent onset of two subcutaneous nodules located on the digits of her upper extremities is described. Initially, a single systemic disorder was considered; yet, the lesions differed in morphology and consistency. Microscopic examination of the nodules showed a giant cell tumor of tendon sheath and a lipoma. Although Occam's “razor” suggests that multiple lesions in the same person are more likely to represent variable manifestations of a single disorder than several different diseases in that individual, the simultaneously appearing lesions in this patient represented two different conditions.