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NanotechnologyThe Hope for New Generation and Its Therapeutic Applications
Published in Pradipta Ranjan Rauta, Yugal Kishore Mohanta, Debasis Nayak, Nanotechnology in Biology and Medicine, 2019
Dnyaneshwar Rathod, Avinash Kharat, Varsha Wankhade, Mahendra Rai
Selenium is very significant trace element which plays a significant role in the regulation of key cellular functions as selenoproteins (Rayman, 2012). It is an inorganic compound which is found in the form of trigonal and monoclinic crystalline phase. Research have been carried out to examine the application of selenium, and it was observed that Se supplementation can reduce the incidence of different kinds of cancers (Ahmad et al., 2015). Many geographical studies have been noticed that people taking low concentrations of Se in their diets may have maximum cancer mortality rates (Rayman, 2005). However, Se at higher concentrations in the diet is useful as a prooxidant with well-established properties of inhibiting cancer cell growth and also killing them (Aboul-Fadl, 2005). Therefore, the applications of Se compounds in cancer therapy have been strengthened, as proven by much research showing that Se compounds decrease the threat of different kinds of cancers, like exocrine gland, prostate, lung, colon, and liver cancers (Srivastava and Mukhopadhyay, 2013; Beheshti et al., 2013; Gao et al., 2014). The biosynthesized SeNPs from Streptomyces bikiniensis (Ess_amA-1) were screened for anticancer activity and it was observed that SeNPs encourage cell death of Hep-G2 and MCF-7 human cancer cells (Ahmad et al., 2015). Moreover, selenium sulfide is an effective antifungal agent, and it has been used in anti-dandruff hair shampoos for treatment of scalp fungal infections (Eswarapriya and Jegatheesan, 2015).
Mechanical (Hair) Hygrometer
Published in Ghenadii Korotcenkov, Handbook of Humidity Measurement, 2019
The hair hygrometer designed by de Saussure is based on a sorption method. It uses the characteristic of the hair so that its length expands or shrinks the response to the relative humidity (Sonntag 1994). The hair shrinks when humidity drops and swells when humidity increases; similarly, cordage and catgut are shortened and untwisted by moisture. For example, the length of a human hair from which liquid is removed increases by 2.0%–2.5% when relative humidity changes from 0% to 100%. A humidity change takes an effect on the moisture content in such materials. The hair is made from keratin, a protein that is wound into a coil. The turns of the coil are held together by hydrogen bonds. These bonds break in the presence of water, allowing the coil to stretch and the hair to lengthen. The bonds reform when the hair dries, which allows people to style their hair simply by wetting it, shaping it, then drying it. Different types of human hair show different changes in length. However, there is still a relationship between the length of hair and relative humidity. Therefore, manufacturers generally use a bundle of hairs. This averages the individual responses of each strand, since different hairs respond at slightly different rates of expansion and contraction. One should note that the dimensions of various organic materials also vary with their moisture content.
Household and Personal Care Products: Cleaning up and Looking Good
Published in Richard J. Sundberg, The Chemical Century, 2017
Hair is composed mainly of the protein keratin which is structurally similar to the collagen on the skin surface. The outer layer is composed of flattened cells that can absorb moisture. The hair is not connected to the skin surface so that by pushing the skin down, the strand of hair can be cut below the surface. Hair shaft thickness and strength varies with individuals and depends on ethnic background. Thin, fragile hair can result from excess lipid removal by shampoos, bleaching, excessively alkaline treatments, swimming, or exposure to sun and wind. Both fatty acids and glycerides, as well as other lipids such as cholesterol and ceramides, are present in natural sebum and these compounds may be present in hair care products to replace materials lost by shampooing. Because of the anionic character of hair, cationic materials are held by electrostatic attraction. Hair care products may also include protein hydrolysates from wheat, rice, oats, almonds, etc.
Development, characterization and in vivo evaluation of the ointment containing hyaluronic acid for potential wound healing applications
Published in Journal of Biomaterials Science, Polymer Edition, 2022
Thiago Gomes Figueira, Francisco Vieira dos Santos, Sérgio Akinobu Yoshioka
Regarding the presence of hair follicles in Figure 8(a), these are dynamic mini-organs that perform several important immune functions such as the production of chemokines that regulate the migration of dendritic cells in the skin, prevention of oxidative stress and degeneration process [30, 31]. Hair follicles have a hair cycle formed by a regeneration system that goes through three phases: growth (anagen), regression (catagen) and rest (telogen) under the influence of growth factors and other signalling molecules [32]. Besides, human follicle dermal papilla cells help regulate hair follicle growth and development [33]. Evidence shows that human follicle dermal papilla cells are associated with vascular remodelling and wound healing through the action of vascular epithelial growth factor (VEGF) and growth factors secreted by hair follicles, respectively [34–37]. Ansell et al. [38] reported that in vivo wound healing is associated with changes in epithelial, endothelial, and inflammatory cell types. Gene profiling results revealed a clear correlation between the transcription of genes beneficial for wound healing and those regulated during the anagen phase of the hair cycle in non-wound skin.
Heparinized PCL/keratin mats for vascular tissue engineering scaffold with potential of catalytic nitric oxide generation
Published in Journal of Biomaterials Science, Polymer Edition, 2018
Xiuzhen Wan, Yanfang Wang, Xingxing Jin, Pengfei Li, Jiang Yuan, Jian Shen
Keratins are the chief proteins in hair, skin, fur, wool, horn, and feathers. Keratins have a variety of biomedical applications including wound dressing [6–8], device coating [9], cell encapsulant [10], and ocular surface reconstruction [11,12], drug carrier [13,14], scaffold for tissue engineering[15]. Their outstanding cytocompatibility is owe to the cell adhesion sequences of RGD (Arg-Gly-Asp) and LDV (Leu-Asp-Val) [16]. Yen et al. have coelectrospun fibroin and keratin for tissue-engineered vascular grafts [17]. However, blood clotting nature of keratins limits its applications in blood-contacting materials [18–20]. Keratin-based hemostatic powder or sponge has been demonstrated [21]. Keratins would induce platelet adhesion and aggregation as well as intrinsic blood coagulation. Immobilization of heparin is a common approach to improve the blood compatibility. Heparin is an effective inhibitor of blood coagulation, which reduces in vitro and in vivo platelet adhesion and aggregation [22,23]. Furthermore, heparin selectively enhances the growth of endothelial cells, while inhibits migration and proliferation of vascular smooth muscle cells [24–26].
Protein–based electrospun nanofibers: electrospinning conditions, biomedical applications, prospects, and challenges
Published in The Journal of The Textile Institute, 2022
Md Nur Uddin, Md. Jobaer, Sajjatul Islam Mahedi, Ayub Ali
Keratin proteins, which are found in epithelial cells, can be derived from hair, wool, and feathers (He et al., 2020). Due to the ability to self–assemble into fibrous structures, keratin is more cytocompatible and non–immunogenic than collagen and elastin (Fearing & Van Dyke, 2014; Reichl, 2009). It is difficult for water to dissolve the arginine-glycine-aspartic acid (RGD) pattern in keratin proteins, although it can be degraded by bacteria. As a result of these advantages, it has been used to manufacture biological materials. The poor viscoelasticity and large keratin molecular weight make electrospinning difficult (Yıldız et al., 2020).