Prevalence of dermatological manifestations of coronavirus disease 2019 (COVID‐19) is estimated between 0.25% and 3% in children and adolescents. In this review article, we decided to describe the cutaneous and histopathological manifestations of COVID‐19 infection in pediatrics. We searched published articles in PubMed database for key words of “children” or “pediatric” and “cutaneous” or “dermatology” or “skin” and “COVID‐19” or “SARS‐CoV‐2” or “Coronavirus disease 2019” in abstract or title from December of 2019 until September 2020. Finally, 38 articles were selected. The majority of patients were between 11 and 17 years old with predominantly male gender. Most of the patients were either asymptomatic or had a few general symptoms. The latency time from appearance of general symptoms to cutaneous ones was between 1 day and weeks. Skin lesions faded between 3 and 88 days without any sequelae, spontaneously or with either topical or systemic corticosteroids. Skin manifestations were chilblain‐like (pseudochilblain), erythema multiforme‐like, dactylitis, acral erythema, acute urticaria, livedo reticularis, mottling, acro‐ischemia, generalized maculopapular lesions, eyelid dermatitis, miliaria‐like, varicelliform lesions, and petechiae and/or purpura. Kawa‐COVID‐19 patients were presented more frequently with cardiogenic shock, neurological symptoms, lymphocytopenia, and thrombocytopenia as compared to classic Kawasaki's disease. Furthermore, more number of cases were resistant to the first‐line treatments.

Melasma is a recalcitrant pigmentary disease with a complex pathogenesis. Monotherapy often results in unsatisfactory results with high recurrence rate. In this review article, we evaluate efficacy of energy‐based devices combination therapy for melasma. We reviewed published literature since 2010 up to November 2020 regarding adjuvant therapy of energy‐based devices with other treatment modalities in the treatment of melasma. After final selection, we assessed 49 articles. Energy‐based devices include lasers, non‐coherent lights, radiofrequency, iontophoresis, sonophoresis, microneedling, and microdermabrasion. Adjuvant therapies other than energy‐based devices were lightening agents, chemical peels, platelet rich plasma (PRP) and mesotherapy. Combination of Q‐switched neodymium‐doped: yttrium, aluminum, and garnet (QSNY) with either intense pulsed light therapy (IPL) or pulsed‐dye laser (PDL) are recommended in recalcitrant melasma in patients with light skin photo types and with dilated skin vessels (especially with PDL). Combination of fractional microneedling radiofrequency or microneedling with QSNY leads to promising results and is a safe treatment modality, especially in darker skin types. Application of topical lightening agents in combination with laser therapy leads to higher efficacy with less adverse effects (post‐inflammatory hyperpigmentation) and rebound of melasma. Combination of ablative techniques with QSNY is not recommended, due to the high risk of permanent adverse effects such as guttate hypopigmentation and exacerbation of melasma.

BackgroundSkin cancers are the most common cancers around the world. Cutaneous malignant melanoma (CMM) is the malignancy of melanocytes that are mainly located in the skin and mucous membranes.ObjectiveThis study tried to evaluate the incidence and mean survival time of cutaneous malignant melanoma (CMM) in Yazd, Iran. It seems that the epidemiology and clinical aspects of CMM in Iran are different from those in other parts of the world; also due to the limited and scattered studies there isn't lot in the literature regarding CMM in Iran.Materials and MethodsThis study used data obtained from the cancer registry center in the province of Yazd for a period of 21 years (1988 – 2008). Population and statistical data were gathered from “National Organization for Civil Registration”. Population-based data were analyzed, focusing on the incidence and mean survival time over this 21 year period.ResultsThe mean incidence rate for CMM in Yazd-Iran between 1988 and 2008 was 0.40 per 100,000 for males and 0.27 per 100,000 for females per year, and the incidence of CMM was relatively constant during this period of time. The mean survival rates for women were better than men (80.5% and 76.3% respectively).ConclusionsCMM in Yazd is a low-incidence skin tumor that shows a relatively fixed incidence between 1988 and 2008, Higher incidences of CMM were found in sun-exposed areas (especially head and neck areas), with more incidence in men. Skin cancers and CMM incidence in Iran is lower than western countries, most probably due to geographical zone, genetic factors, skin type, society-related customs including clothing styles.

Purpose: Combination of benzoyl peroxide (BPO) with topical antibiotics can lead to higher efficacy and less bacterial resistance, but it in turn increases adverse effects such as skin irritability and dryness. In this study, the efficacy of combination therapy of niosomal BPO 1% and clindamycin (CL) 1% is compared with niosomal CL in acne vulgaris. Methods: This is a double-blind clinical trial study on 100 patients with acne vulgaris in Afzalipour hospital in Kerman. Patients were randomly divided into 2 groups (case and control). The case group received niosomal combination of BPO 1% and CL 1%.The control group received niosomal CL1%. The efficacy of treatment protocols was evaluated in 2nd, 4th, 8th and 12th weeks of treatment by counting lesions (severity and grading acne lesions) and quality of life (QoL). Furthermore, side effect were evaluated at each treatment visits. Results: The reduction in mean percentage of acne lesions in case group (treated with BPO 1% and CL1%) (64.21%) was higher than control group (treated with niosomal CL 1%) (59.04%), but the statistical difference was not significant. Sum of excellent and good results were found in 80% and 76.1% of case and control groups, respectively (P=0.377). Also adding BPO to the treatment formulation in case group did not increase adverse effects, as statistical difference between 2 groups was not significant. Conclusion: Combination of niosomal BPO 1% and CL 1% in treatment of acne vulgaris showed higher efficacy with no increase in adverse effects in comparison with niosomal CL 1%, but the statistical difference was not significant.

We searched articles with keywords of "acne" AND "erythema" OR "post-acne erythema" OR "post-inflammatory" AND "laser" OR

Vitiligo is an acquired immune-mediated pigmentary skin disease affecting 1%-2% of worldwide population. 1 First-line therapy for restricted and extensive involvement is topical therapy (corticosteroids [TCS] and calcineurin inhibitors [TCI, tacrolimus, and pimecrolimus]) and narrow-band ultraviolet B (NB-UVB), respectively. 2-5 Nowadays, lasers are used for treatment of difficult-to-treat areas and refractory lesions. Monochromatic excimer laser (MEL)/excimer light (EL) was the first laser used in treatment of vitiligo. Ablative resurfacing

Carboxytherapy has been used in the treatment of autoimmune skin diseases such as psoriasis and morphea. Carboxytherapy has antioxidant effects, and leads to better tissue oxygenation, and release of growth factors. In this article, we decided to evaluate efficacy of combined carboxytherapy and narrowband‐ultraviolet B (NB‐UVB) compared to NB‐UVB alone in the treatment of vitiligo. This is a prospective, split‐body double‐blind comparative study performed in patients with generalized stable vitiligo in acral areas and extremities referred to dermatology clinic of Afzalipour hospital in Kerman University of Medical Sciences. NB‐UVB was performed three times a week in non‐consecutive days for 4 months. In each patient, one lesion was randomly treated with carboxytherapy (weekly sessions for total of 16 sessions). Efficacy of treatment was evaluated by percentage of repigmentation of the lesions. Chi‐square test and analysis of variance test (ANOVA) were used to compare efficacy of treatment based on demographic features of the patients and clinical features of the lesions, respectively. Twenty‐eight patients with mean age of 32.35 ± 7.37 years old completed the study. At the end of the treatment, 37% of the patients in combination therapy group demonstrated more than 75% improvement compared to 0% in the monotherapy group (p = 0.001). There was no significant difference between either demographic features of the patients (age, sex, and skin phototypes) or duration of disease with efficacy of the treatment in both groups. Combination of carboxytherapy with NB‐UVB leads to higher percentage of repigmentation and patients' satisfaction compared to monotherapy with NB‐UVB.

SUMMARYIn this paper, we present a novel structure of a snake-like robot. This structure enables passive locomotion in snake-like robots. Dynamic equations are obtained for motion in a horizontal plane, using Gibbs–Appell method. Kinematic model of the robot include numerous nonholonomic constraints, which can be omitted at the beginning by choosing proper coordinates to describe the model in Gibbs–Appell framework. In such a case, dynamic equations will be significantly simplified, resulting in considerable reduction of simulation time. Simulation results show that, by proper selection of initial conditions, joint angles operate in a limit cycle and robot can locomote steadily on a passive trajectory. It can be seen that the passive trajectory is approximately a Serpenoid curve.