The assessment of drug activity in skin is hampered by the lack of adequate methods for quantitative measurement of drug penetration in skin. Therefore, a new method was developed with the following features. The drug, hydrocortisone, chosen for its clinical and pharmaceutical importance, was applied under occlusive dressing for varying time intervals. Small skin samples, which ranged from 0.5 to 20 mg in size, were removed, in vivo, from humans or animals by a new dermatome serial slicing technique. The amount of hydrocortisone absorbed into the epidermis and/or dermis was determined by a new spectrophotofluorometric procedure, based on an older technique described for blood. The tissue levels were then correlated with simultaneously determined skin function measurements. The assay was done at 470 mμ and 525 mμ excitation and emission wavelengths, respectively. Hydrocortisone was extracted from homogenized tissue with dichloromethane. Fluorescence was developed with 85:15 w/w sulphuric acid - ethyl alcohol solution. Hydrocortisone was found in epidermis, but not in dermis. These results confirm current theories on hydrocortisone depot formation in the epidermis. Among the 14 patients examined, the concentration of hydrocortisone in epidermis varied greatly from 20 μg to 358 μg per Gm wet weight of tissue. Exploratory correlations between skin respiration rates, vasoconstriction, and the amount of hydrocortisone in epidermis have been done. The analytical reliability has been discussed. / Pharmaceutical Sciences, Faculty of / Graduate

To date, most studies of the cestode cuticle have been carried out on adult worms and in no instance has an attempt been made to correlate ultrastructural and histochemical observations. The present study was designed to obtain information on both the histochemical composition and the ultrastructure of the plerocercoid cuticle of the pseudophyllidean cestode Schistocephalus solidus (Müller, 1776) and to study any changes which might occur during plerocercoid differentiation. Initially, this work has demonstrated that the plerocercoid tegument of S. solidus is of the same fundamental type as that of previously described cestodes. An outer anucleate but cellular region (the cuticle) is connected by cytoplasmic tubes to nucleated tegumental cells lying in the parenchyma. It has been shown that the pore canals of S. solidus are different from any described for other cestodes and it is suggested on morphological grounds that they may function in a secretory capacity. In addition, the pore canals provide a direct connection between certain parenchymal cells and the external medium. Papilla-like cuticular processes on the cuticular surface have been described and both adhesive and absorptive functions are suggested for these structures. It has been shown that the cuticular processes are not present in the smallest forms studied but rather appear at about the same time as the worm becomes infective. Changes in the histochemical and ultrastructural composition of the cuticular matrix have been described. It is probable that increased plerocercoid growth is accompanied by a change in cuticular composition from a more proteinaceous state to one which is largely carbohydrate. A surface sulphomucin-basic protein complex has been described and partially characterized. Possible functions have been suggested for this layer. RNA as well as acid and alkaline phosphatases were found in the cuticle and the possible significance of these substances in cuticular synthetic activities is considered. It is suggested that plerocercoid cuticular differentiation may consist of two phases: (1) an initial phase in which various mechanisms are elaborated to allow survival in the vertebrate intestine, and (2) a second phase in which the plerocercoid is modified to permit prolonged growth in the stickleback coelom. / Science, Faculty of / Zoology, Department of / Graduate

Evaluation of several methods of fixing chicken skin for scanning electron microscopy (SEM) indicated standard chemical fixation using glutaraldehyde and osmium tetroxide followed by chemical dehydration with 2,2-dimethoxypropane to be the method of choice. SEM revealed that chicken skin has a convoluted surface. Two types of chicken skin, distinguishable on the basis of chemical composition and appearance were observed. Type I has a filamentous surface with 55% moisture and 25% fat, whereas Type II skin has a globular appearance, 52% fat and 33% moisture. The fatty acid profiles of Types I and II skin are the same. Bacteria have greater affinity for Type II than Type I skin. Attachment studies indicated that Salmonella typhimurium quickly attach to the skin surface and cannot be removed easily by washing with water or with water containing a surfactant. / Land and Food Systems, Faculty of / Graduate

Radiation therapy has been shown to increase local and regional control as well as overall survival with breast cancer, but the vast majority of patients develop acute skin reactions, which are in part related to microvascular changes. These reactions vary between different skin sites. The aim of this work is to determine the absorbed dose to the skin by measurements and investigate if there is a correlation between the absorbed dose at different areas of the breast and the local changes in microcirculation in the skin after breast cancer radiotherapy. The study includes characterisation of the Gafchromic EBT3 film and Epson Perfection V600 Photo scanner which are used for absorbed dose determination. The measurements were done both on an anthropomorphic female phantom and on a patient undergoing breastcancer radiotherapy. Twenty-one pieces of film (2x1 cm2) were placed on the surface ofthe breast (both for the phantom and patient) and irradiated with a prescribed dose to the target of 2.66 Gy with two opposed fields using 6 MV beam. It was observed that mainly 45-64 % of the prescribed dose was deposited at the surface, both for the phantom and patient. Using laser speckle contrast imaging and polarised light spectroscopy, the regional changes in mean blood perfusion and in mean red blood cell concentration (RBCC) at the end of the treatment with a total prescribed dose of 42.6 Gy, compared to baseline, were measured in both the treated and untreated breast of the same patient. Although marked increases in perfusion were seen in different areas of the treated breast, there was no signicant correlation between the changes in perfusion and the absorbed dose at these areas. However, a statistical correlation was found between the changes in RBCC and the absorbed skin dose at the same areas. To further elucidate the relation between the changes in skin microcirculation and the absorbed radiation dose during breast cancer radiotherapy, future studies using a larger number of patients are needed.

Skin collimation in electron therapy ensures sharper penumbra and maximal protection to adjacent critical structures. It also provides a better clinical dose to the target and avoids recurrences at the periphery. The thickness of the electron skin collimation must be adequate for shielding purposes, not too thick to cause discomfort to the patient and be conformal to the skin. This study assessed the clinical potential of machined brass skin collimation with variable thickness. Brass transmission factors for 6, 9, and 12 MeV electron beams were measured and used to determine the skin collimation clinically acceptable thickness. Dosimetric performance of the variable thickness skin collimation was evaluated for 9 MeV electrons within a rectilinear water-equivalent phantom and a water-filled head phantom. Results showed the variable thickness skin collimation is dosimetrically equivalent to the uniform thickness collimation. Favorable dosimetric advantages for brass skin collimation for small electron fields were achieved. / Includes bibliography. / Thesis (PMS)--Florida Atlantic University, 2021. / FAU Electronic Theses and Dissertations Collection

Effect of the concentration of amino-decorated polyamidoamine dendrimers with ethylenediamine core at the (trans)dermal delivery of 5-Fluorouracil Pavlína Chladová Dendrimers are synthetic, symmetrically tree-like branched molecules. They are composed of repeating units (monomers). They have high density of surface functional groups and spherical shape in solution. Since their molecular weight is highly controllable, they are characterized by monodispersity and this is their main difference from classical polymers. Dendrimers have a wide spectrum of applications in biomedicine. Due to the empty space between the branches of the molecule, they can encapsulate drugs, and by conjugation and complexation to the surface groups, they are able to carry even larger drug molecules. Thus, dendrimers can be used as drug delivery systems. In addition, they have been used for skin application of several active molecules, either as topical or transdermal delivery. Suitable properties for (trans)dermal application have been demonstrated for dendrimers which consist of monomers with amine groups and are connected with amide bonds. The goal of this thesis was the preparation of dendrimers with these characteristics and the evaluation of their concentration influence to the permeability of 5-Fluorouracil (5-FU) to human...

Charles University, Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical Technology Supervisor: Dr. Georgios Paraskevopoulos, Ph.D. Consultant: Mgr. Anna Nová ková Author: Denisa Houšková Title of thesis: Effect of the generation of amino-decorated polyamidoamine dendrimers with ethylenediamine core at the (trans)dermal delivery of 5-fluorouracil. Dendrimers can be defined like highly branched, star-shaped macromolecules with nanometer-scale dimensions and unlimited applications in both biological and materials sciences. Polyamidoamine (PAMAM) dendrimers have been used to effectively enhance the (trans)dermal drug delivery of several active substances. Inspired by the structure of PAMAM dendrimers, a new class of dendrimers was designed having amino-functionalized periphery and ethylenediamine core. A repeating motif of bis(2-aminoethyl)glycine was used for generation growth up to the third generation. The new dendritic molecules of zero, first, second and third generation were tested for their ability to enhance the deposition of 5-fluorouracil in the different layers of human skin ex vivo by using Franz diffusion cells. The results suggest that the new dendrimers, at a concentration of 20 mg/mL in 60 % propylene glycol in water as vehicle, are able to deliver 5-fluorouracil at the...

La presente tesis tiene como objetivo presentar la propuesta de introducción en el Perú de la marca coreana de cosméticos SkinFood a través de la adquisición de la franquicia. La marca SkinFood se caracteriza por ofrecer una propuesta única basada en alimentos como insumos primarios, cuidado natural de la piel, fórmulas de eficacia probada e innovación continua debido a la inversión que hace la marca en I&D. En los últimos años, el Perú viene atravesando un crecimiento económico sostenido, que ha impulsado diversos sectores entre los cuales se encuentra el mercado de cosméticos e higiene personal, el cual tiene una proyección positiva para los próximos años, con un incremento del 2015 al 2017 de 5%, 6% y 6%, respectivamente. Este crecimiento también acompañado de cambios en el comportamiento de consumo, entre los cuales tenemos el aumento del consumo de productos de origen natural, que promueven el bienestar y una conducta socialmente responsable. SkinFood innova, pues es la primera marca de belleza desarrollada en base al concepto de alimento para la piel. La empresa desarrolla productos de belleza que contienen el valor nutritivo de los alimentos y utiliza en su manufactura insumos orgánicos de alta calidad y de distinta procedencia. La marca transmite la importancia de mantener una piel saludable, nutrida y consecuentemente bella. Es así que SkinFood se convierte en una propuesta con valor único proveyendo beneficios muy atractivos para el público objetivo en un mercado en franco crecimiento. Como parte de la investigación, se realizó un estudio cualitativo en sesiones de focus groups así como encuestas a mujeres de Lima que acostumbran usar productos de belleza. Los resultados de ambos estudios fueron utilizados en parte para determinar el nicho de mercado así como la validación que el concepto de marca es atractivo para el mercado peruano. El objetivo de mercado es introducir la marca SkinFood con una participación inicial de 1.7% en el primer año, 2.4% en el segundo año y 2.9% en el tercer año en las categorías en las que competimos; cuidado facial y corporal, capilar y fragancias. Para lograr dicha participación se requiere facturar US$ 777,700 en el primer año, US$ 1,162,051 el segundo año y US$ 1,510,666 el tercer año. Es importante indicar que más allá de la inversión de compra de la franquicia, de contar con surtido de productos para la mujer peruana y de poseer posiciones preferenciales en retails que aseguren un tráfico suficiente de personas; este proyecto requiere de una consistente inversión en Marketing y Publicidad, sobre todo para los dos primeros años donde se deberá tener una visión de desarrollo de marca, sentando muy bien la comunicación del posicionamiento y los beneficios clave de los productos para el target seleccionado de 411,445 personas, compuestas por mujeres jóvenes de 15 a 25 años, NSE A, B y C que residen en Lima Moderna , son en su mayoría solteras, estudiantes en etapa escolar o con educación superior, técnica o universitaria. Desde el ámbito psicográfico, pertenecen a las mujeres modernas y a la generación de millennials. Si nos ajustamos a nuestro objetivo de participación de mercado, lograremos captar aproximadamente 7,000 clientes el primer año, 10,000 clientes el segundo año y 12,000 clientes el tercer año. / Tesis

No description available.

No description available.