Ionic Liquids and Deep Eutectic Solvents and Their Use for Dissolving Animal Hair

In recent years, one of the priority areas of research in chemistry has become the processes carried out in an environment of liquid organic salts, the so-called ionic liquids (ILs), which are assessed as environmentally friendly or “green” alternatives to conventional organic solvents. ILs are non-volatile, highly polar solvents that dissolve many organic, inorganic, and organometallic compounds. Since they have no detectable vapor pressure, ILs are considered as potential substitutes for volatile organic compounds traditionally used as solvents. So-called deep eutectic solvents (DES) is a group of ILs that are liquid mixtures of a number of organic and (or) inorganic components taken in a certain ratio (eutectic or close to eutectic). DES deserve a special attention due to their negligible saturated vapor pressure, availability, low cost, as well as ability to dissolve at relatively high concentration of metal salts, metal oxides and various polymers. Particularly DES based on a mixture of choline chloride with urea (DES-1) or a mixture of choline chloride and adduct of urea with hydrogen peroxide (DES-2) give eutectics that are liquid at ambient temperature and have unusual solvent properties, including an ability to dissolve an animal hair in the presence of low concentration of sodium sulfide or ammonium thioglycolate. It was found that depending on the ratio between DES-1 and DES-2 in the mixture of two Deep Eutectic Solvents and the nature of sulfur-containing additive, the solubility of rabbit hair under used conditions, varies from 51% to 79%.

Diagnosis of Rabies via RT-PCR on Skin Samples of Wild and Domestic Animals

In developing countries, brain tissues from rabies suspect animals are not always available for diagnosis for a variety of reasons, such as lack of transport to submit a carcass or the difficulty of removing an animal’s head or brain under field conditions. To enable diagnosis in such cases, there is a need for a reliable method, using an alternative non-neural tissue, which can be removed and submitted to the diagnostic laboratory without special training or equipment. In human medicine, skin is used successfully for the detection of rabies virus antigen using RT-PCR technology. Little work has been done in animals using RT-PCR on skin or extracted hair follicles. The current study was conducted in Grenada on skin from 36 wild and domestic animals, in which rabies virus infection had been confirmed in brain tissue via the direct fluorescent antibody (DFA) test, and in 31 negative control animals. RT-PCR on skin yielded a sensitivity of 97.2% (35/36) and a specificity of 100% (31/31). It is concluded that the examination of skin samples via RT-PCR provides a valuable diagnostic alternative in those cases where brain tissue is not readily available.

Labeling Algorithm for Face Detection Using Skin and Hair Characteristics

This research presents an algorithm for face detection based on color images using three main components： skin color characteristics, hair color characteristics, and a decision structure which converts the obtained information from skin and hair regions to labels for identifying the object dependencies and rejecting many of the incorrect decisions. Here we use face color characteristics that have a good resistance against the face rotations and expressions. This algorithm is also capable of being combined with other methods of face recognition in each stage to improve the detection.

The Effect of Novel Low Energy Pulsed Light Combined with Galvanic Energy for Home-Use Hair Removal of Dark Skin

Background and Objectives: Permanent reduction of unwanted hair on skin types V and VI is the most challenging procedure among all hair removal technologies based on selective absorption of light or laser. The objective of this study is to evaluate the safety and efficacy of a low energy pulsed-light device combined with galvanic energy, intended for home-use hair removal on dark skin. Materials and Methods: Fifteen women with skin types V and VI and dark terminal hair in axillaarea self-administrated 6 treatments at 2 week intervals, using a hand-held IPL combined with galvanicenergy device, using HPL (Home Pulsed Light) technology. Hair count and photographs were performed pre-treatment and 1 and 3 months after the last sixth treatment. Adverse events and subject satisfaction scores were recorded. Results: All patients showed a positive clinical response to treatment, with reduction of unwanted hair. Hair counts were significantly reduced by 57.3% 1 month following last treatment and by 44.5% 3 months following last treatment. No adverse events were recorded. Subject satisfaction scores of the device usability and the treatment outcome were high. Conclusions: Low energy pulsed light combined with galvanic energy may be applied safely and effectively for at-home hair removal for people with dark skin types V and VI.

Study on the Morphological Characteristics of Skin and Hair Coat of Yak and the Adaptability to the Cold Living Environment

Selecting 6 heads of new yak strains(the offspring of reciprocal cross of F1 produced by wild yak male mated with domestic yak female)and 6 domestic yaks at 3 and 12 age in months respectively at Datong Yak Farm of Qinghai Province. This paper was studied for the morphological characteristics of the skin and hair coat of yak and their adaptability to the cold living environment in Qinghai-Tibetan plateau. The results indicated that it should be of vital importance marker for the morphological characteristics of the skin and hair coat with two type of yaks at 3 and 12 age in months and their regulations of growth and development to adapt to the cold living environment in Qinghai-Tibetan plateau,The main morphological indexes of the skin and hair coat of the rearing new yak strain were higher than those of the domestic yaks at the same age in months, or speak precisely, the new yak strain was more powerful adaptable to the alpine cold living environment than that of the domestic yaks. The resvlts above provided scientific basis for the native strain breeding of yak and the new yak strain rearing.

Constructing skin-equivalents using hair follicle stem cells

Objective： To establish the method of constructing skin-equivalents （SE） using hair follicle stem cells （HFSC）. Methods： K19 positive cells derived from hair were cultivated using serum-free medium KGM and seeded on dermal equivalents （DE）. After the culture between the air-liquid interface for 14 days, SE were harvested and used for evaluation. Results： K19 positive cells chosen as HFSC were located in bulge of out root sheet in hair follicle. Cultivated HFSC could build a fully developed, multi-layered epidermis on the basis of DE, resembling the skin structure. Conclusion： HFSC located in out root sheet can differentiate into kerafinocyte in vitro and be used for SE construction.

不同胚层来源成体干细胞修复周围神经损伤

背景:成体干细胞疗法是周围神经损伤修复与再生领域的研究热点之一。中胚层被视为成体干细胞的理想来源,间充质干细胞具有获得率高、来源广、增殖快等优异性能。而外胚层来源成体干细胞,尤其是神经嵴干细胞,具有神经源性,越来越受到研究人员的关注。目的:对来自外胚层和中胚层的多功能成体干细胞在周围神经损伤修复与再生中的作用及机制进行简要综述,探究不同来源成体干细胞的研究进展与应用前景,并结合临床研究,探讨成体干细胞疗法潜在的应用价值以及亟待解决的问题。方法:第一作者于2024年2月应用计算机在PubMed和SinoMed数据库检索2001年12月至2024年2月相关文献,以“ectodermal stem cells,mesenchymal stem cells,peripheral nerve injury,repair,regeneration”为英文检索词,以“外胚层干细胞、间充质干细胞、周围神经损伤、修复、再生”为中文检索词,最终纳入69篇文献进行分析论述。结果与结论:①外胚层来源成体干细胞具有优异的分化和再生潜能,尤其是毛囊神经嵴干细胞、嗅干细胞、牙外胚层干细胞等,具有神经源性,可在体外表达神经特异性标志物,但目前缺少临床试验研究。②中胚层来源成体干细胞种类多、易获得及纯化,其中骨髓间充质干细胞和脐带间充质干细胞在周围神经损伤修复的应用疗效及安全性方面有相关临床试验支持,能改善感觉及运动神经传导,且在随访中未出现并发症和明显不良反应。骨髓间充质干细胞的获取需行侵入性外科手术且要求患者与捐赠者骨髓配型吻合,应用受到一定限制;而脐带间充质干细胞虽无需侵入性获取,但分离较困难且表型不稳定。③内胚层来源成体干细胞常难以在体外生长,应用受限,目前应用于临床的可能性低。④综合来看,骨髓间充质干细胞仍为周围神经损伤干细胞治疗的首选细胞,适用于无外科手术禁忌且符合配型要求的情况,其次为脐带间充质干细胞,辅以分离方法的改进和表型稳定性的提高策略。⑤牙外胚层干细胞以及脂肪间充质干细胞具有较高应用潜能,有待进一步临床试验,其他外胚层、中胚层来源成体干细胞各以其优异特性在动物及细胞实验研究中具有显著优势。

Vital roles of stem cells and biomaterials in skin tissue engineering

Tissue engineering essentially refers to technology for growing new human tissue and is distinct from regenerative medicine. Currently, pieces of skin are already being fabricated for clinical use and many other tissue types may be fabricated in the future.Tissue engineering was first defined in 1987 by the United States National Science Foundation which critically discussed the future targets of bioengineering research and its consequences. The principles of tissue engineering are to initiate cell cultures in vitro, grow them on scaffolds in situ and transplant the composite into a recipient in vivo. From the beginning, scaffolds have been necessary in tissue engineering applications. Regardless, the latest technology has redirected established approaches by omitting scaffolds. Currently, scientists from diverse research institutes are engineering skin without scaffolds. Due to their advantageous properties, stem cells have robustly transformed the tissue engineering field as part of an engineered bilayered skin substitute that will later be discussed in detail. Additionally, utilizing biomaterials or skin replacement products in skin tissue engineering as strategy to successfully direct cell proliferation and differentiation as well as to optimize the safety of handling during grafting is beneficial. This approach has also led to the cells' application in developing the novel skin substitute that will be briefly explained in this review.

Mammalin cochlear supporting cells transdifferentiation into outer hair cells

Objective To study the recovery of the outer hair cells in the bat cochlea after gentamicin exposure. Methods Bats were injected with a daily dose of gentamicin for 15 consecutive days and bromodeoxyuridine (BrdU) was given from day 16 to day 40 of this recovery phase. Hearing was assessed by overt acoustic behavior and auditory brainstem responses analysis, which was performed one day prior to the first injection and a day after the last injection (day 16). On day 40 animals were sacrificed for detection of cells that could take up BrdU. Results After 15 days of gentamicin treatment, all of the animals were proved to be deafened with significant increases of ABR thresholds, compared with control group. The findings in immunocytochemical stained samples and scanning electron microscopy revealed that BrdU labeled nuclei were observed in the cochlea in all of the deafened animals most commonly in the regions of the first-row and second-row Deiter’s cells (DCs) and occasionally in the regions of the third-row DCs. Conclusion We suggest that, under sufficient drug and enough time, the bat cochlear supporting cells can directly transdifferentiate into the outer hair cells after aminoglycoside exposure. This transdifferentation process is essential for repair of outer hair cells and recovery of normal function after gentamicin exposure.

Effects of Nicotinamide on Mouse Skin Tumor Development and Its Mode of Action

Nicotinamide (NA), a naturally occuring vitamin and a protease inhibitor, has been shown to be effective in treating some skin ailments. It inhibits cell proiferaion and induces cell differentiation. This report shows the effects of NA on mouse skin tumor development and on the critical events involved in this process. NA reduced tumor growth, inhibited the 12-O-tetradecanoylphorbol-13-acetate (TPA) induced ornithine decarboxylase activity, but induced the transglutaminare activity which was inhibited by TPA under different experimental conditions.The effects of NA on ornithine decarboxylare (ODC) and transglutaminase (TG) indicated that nicotinamide (NA) probably programmmed the cells for their death in the natural course of time, i.e. programed cell death. This observation indicates that NA might be a better agent for the detailed study and for the better use in prevention of cancer alone or in combination with other drugs.

Establishment of Mus Skin Photo-damage Model by 8-MOP plus UVA Irradiation

To establish a simple and reliable animal model of skin photo-damage, 20 mice were treated with 8-MOP and exposed to UVA （UVA 320-400 nm） for 24 h. After irradiation, the structure of the epidermis and dermis, collagen fibers, elastic fibers were observed by using HE staining and Weigert technique and compared with the normal controls. The acanthosis and epidemis proliferation with accompanying hyperkeratosis and parakeratosis were observed. Inflammatory infiltration was noted in the dermis. The elastic fibers became coarse, irregularly arranged and clustered, with their number increased. The collagen fibers showed obvious degeneration and some amorphous materials could also be observed. The blood vessels were irregularly dilated and vascular walls were thickened, with infiltration of inflammatory cells. It is concluded that murine photodamage model can be quickly, conveniently and reliably established by means of 8-MOP/UVA.

Histochemical Localization of Glutathione Dependent NBT-Reductase in Mouse Skin

Objective Localization of the glutathione dependent Nitroblue tetrazolium (NBT) reductase in fresh frozen sections of mouse skin and possible dependence of NBT reductase on tissue thiol levels has been investigated. Methods The fresh frozen tissue sections (8m thickness) were prepared and incubated in medium containing NBT, reduced glutathione (GSH) and phosphate buffer. The staining for GSH was performed with mercury orange. Results The activity of the NBT-reductase in mouse skin has been found to be localized in the areas rich in glutathione and actively proliferating area of the skin. Conclusion The activity of the NBT-reductase seems to be dependent on the glutathione contents.

EpiSkin皮肤模型应用概述

本文主要综述了EpiSkin皮肤模型在化妆品刺激和腐蚀性能的动物替代试验中发挥的作用,同时也介绍了其构成及检测原理。

Hair follicles as a target structure for nanoparticles

For at least two decades,nanoparticles have been investigated for their capability to deliver topically applied substances through the skin barrier.Based on findings that nanoparticles are highly suitable for penetrating the blood--brain barrier,their use for drug delivery through the skin has become a topic of intense research.In spite of the research efforts by academia and industry,a commercial product permitting the nanoparticle-assisted delivery of topically applied drugs has not yet been developed.However,nanoparticles of approximately 600 nm in diameter have been shown to penetrate fficiently into the hair fllieles where they can be stored for several days.The successful loading of nanoparticles with drugs and their triggered release inside the hair fllile may present an ideal method for localized drug delivery.Depending on the particle size,such a method would permit targeting specific structures in the hair fllicles such a stem ells or immune cells or blood vessels found in the vicinity of the hair follicles.

A New Hybrid Model for Segmentation of the Skin Lesion Based on Residual Attention U-Net

Skin segmentation participates significantly in various biomedical applications,such as skin cancer identification and skin lesion detection.This paper presents a novel framework for segmenting the skin.The framework contains two main stages:The first stage is for removing different types of noises from the dermoscopic images,such as hair,speckle,and impulse noise,and the second stage is for segmentation of the dermoscopic images using an attention residual U-shaped Network(U-Net).The framework uses variational Autoencoders(VAEs)for removing the hair noises,the Generative Adversarial Denoising Network(DGAN-Net),the Denoising U-shaped U-Net(D-U-NET),and Batch Renormalization U-Net(Br-U-NET)for remov-ing the speckle noise,and the Laplacian Vector Median Filter(MLVMF)for removing the impulse noise.In the second main stage,the residual attention u-net was used for segmentation.The framework achieves(35.11,31.26,27.01,and 26.16),(36.34,33.23,31.32,and 28.65),and(36.33,32.21,28.54,and 27.11)for removing hair,speckle,and impulse noise,respectively,based on Peak Signal Noise Ratio(PSNR)at the level of(0.1,0.25,0.5,and 0.75)of noise.The framework also achieves an accuracy of nearly 94.26 in the dice score in the process of segmentation before removing noise and 95.22 after removing different types of noise.The experiments have shown the efficiency of the used model in removing noise according to the structural similarity index measure(SSIM)and PSNR and in the segmentation process as well.

Surface Morphology Investigation of Tunisian Dromedary Hair

In raw materials of dromedary hair, there are two distinct fibre populations： The fine one is of textile relevance and the coarse one is rather worthless and must be as a rule separated prior to spinning and subsequent processing. The fibre surface morphology and fibre fineness of Tunisian dromedary hair has been investigated by means of scanning electron microscope （SEM）. SEM microscopic method provides the fibre diameter, the scale shape, the scale frequency and scale height. The results show that dehaired dromedary fibre presents a relatively low mean fibre diameter （≈ 17 μm） with a high coefficient of variation （CV ≈ 25%）. The scales of the dromedary fibre are on average extremely long and quite visible, they tend not to protrude from the fibre, appear almost convex, and provide a wavy appearance in profile of the relatively coarse fibre. On counting the scale frequency, that is, the number of scale margins within a determined fibre length of 100 μm on the surface of a fine （diameter 〈 30 μm） and coarse （diameter 〉 30 μm） dromedary fibre, comes out roughly five at eight and eight at twelve scale margins, respectively. The mean height of the cuticle scale is 0.12μm and 0.24 μm, respectively, for fine and coarse dromedary fibre. These explain why dromedary fibres present a soft touch due to the prominence of the scale edges. This aspect of the surface structure has a high correlation with the felting capacity of the matter, and contributes to the concepts of handle and gloss.

Hair Analysis of Mammals of Brazilian Wildlife for Forensic Purposes

Wildlife trafficking is classified as the fourth largest illegal commerce in the world. Taxonomic identification of wildlife is an ordinary process for forensics experts. The aim of this study was to analyze animal’s hair from Brazilian’s wildlife through microscopic and compare morphology of bristle among species analyzed. Hair samples of nine species were analyzed. Glass slides were analyzed through optical microscopy and following measurements were obtained: total length, medulla diameter, overall diameter and overall ratio diameter of the medulla’s diameter. The images obtained at identification of animals through the morphology of hair and the statistics analysis corroborates in favor for the validation of the technique.

Influence of Shaving Behavior on Skin Physiological Properties and Sensory Discomfort of Chinese Men

Men's facial skin is ubiquitously affected by their shaving behaviors. Skin physiological parameters and the degree of discomfort were investigated on healthy Chinese male volunteers. The effect of immediate shaving and long-term shaving was compared, and more parameters such as skin integrity, pigmentation and texture were significantly influenced by long-term shaving. Sensory assessment also showed severer discomfort degree after long-term shaving. The results indicated that long-term shaving has more impact on skin condition than immediate shaving. Furthermore, the skin damage caused by shaving can be relieved by appropriate shaving care habits.

唐志铭教授运用“肺主皮毛”理论辨治银屑病临证经验

“肺主皮毛”理论是肺与皮毛关系的高度概括,可用于指导多种皮肤病的诊治。唐志铭教授在银屑病的临床诊治中,运用“肺主皮毛”理论,从肺论治,疗效卓著。笔者通过跟师学习、分析研究唐志铭教授临床治疗银屑病的临床医案,从病机、治法、用药等方面总结唐志铭教授治疗银屑病的临证经验,并遴选验案以佐证。

基于角色建模的运动员动作动画交互演示方法

为了更好地展示动画交互效果,提升用户的体验感,提出基于角色建模的运动员动作动画交互演示方法。基于人体骨骼模型和骨骼蒙皮实现角色建模,建立三维场景,为人物活动提供虚拟环境。通过PD控制器实现对角色模型的行为控制,虚拟交互技术则实现了动画制作交互式演示。实验结果表明:该研究方法能够较好地完成人体动作交互演示,并通过交互演示延迟时间验证,证明该方法应用下的交互演示灵敏度实现了研究的预期目标。