In several applications of casting, dendritic microstructure is not desirable as it results in poor mechanical properties. Enhancing the fluid flow in the mushy zone by stirring is one of the means to suppress this dendritic growth. The strong fluid flow detaches the dendrites from the solid-liquid interface and carries them into the mold to form slurry. The detached dendrites coarsen in the slurry and form into rosette or globular particles based on processing conditions. This slurry offers less resistance to flow even at a high solid fraction and easily flow into the die-cavity. The above principle is the basis of a new manufacturing technology called “semi-sold forming” (SSF), in which metal alloys are cast in the semi-solid state. This technique has several advantages over other existing commercial casting processes, such as reduction of macrosegregation, reduction of porosity and low forming efforts. A major challenge existing in semisolid manufacturing is the production of metallic slurry in a consistent manner. The main difficulty arises because of the presence of a wide range of process parameters affecting the quality of the final product. An established method of producing slurry is by stirring the alloy using an electromagnetic stirrer. From an elaborate review of literature, it is apparent that solidification in presence of electromagnetic stirring involves a wide range of shear and cooling rates variation. However, the CFD models found in the literature are generally not based on accurate rheological properties, which are known to be functions of the relevant process parameters. Hence, there is a clear need for a comprehensive numerical model for such a solidification process, involving accurate rheological data for the semisolid slurry subjected to a range of processing conditions. The objective of the present work is to develop a numerical model for studying the transport phenomena during solidification with linear electromagnetic stirring. The study is presented in the context of a billet making process in a cylindrical mould using linear electromagnetic stirring. The mould consists of two parts: the upper part of the mould is surrounded by a linear electromagnetic stirrer forming the zone of active stirring, and the lower part of the mould is used to cool the liquid metal. The material chosen for the study is Al-7.32%Si (A356) alloy, commonly used for die casting applications. A complete numerical model will therefore have two major components: one dealing with rheological behavior of the semisolid slurry, and the other involving macroscopic modeling of the process using computational fluid dynamics (CFD) techniques. For the latter part of the model, determination of rheological behavior of the slurry is a pre-requisite. The rheological characteristics of the stirred slurry, as a function of shear rate and cooling rate, is determined experimentally using a concentric cylinder viscometer. Two different series of experiments are performed. In the first series, the liquid metal is cooled at a constant cooling rate and sheared with different shear rates to get the effect of shear rate on viscosity. In the second series of experiments, the liquid metal is cooled at different cooling rates and sheared at a constant shear rate to obtain the effect of cooling rate on viscosity. During all these experiments, the shear rate is calculated from the measured angular velocity of spindle using inductive position sensor; viscosity of the slurry is calculated based on the torque applied to the slurry and angular velocity of the spindle; and the solid fraction is calculated from measured temperature of the slurry based on Schiel equation. From these data, a constitutive relation for variable viscosity is established, which is subsequently used in a numerical model for simulating the transport phenomena associated with the solidification process. The numerical model uses a set of single-phase governing equations of mass, momentum, energy and species conservation. The set of governing equations is solved using a pressure based finite volume technique, along with an enthalpy based phase change algorithm. The numerical simulation of this process also involves modeling of Lorentz force field. The numerical study involves prediction of temperature, velocity, species and solid fraction distribution. First, studies are performed for a base case with a moderate stirring intensity of 250A primary current and 50 Hz frequency. It is found that the electromagnetic forces have maximum values near the mould periphery, which results in an ascending movement of the slurry near the mould periphery. Because of continuity, this slurry comes down along the axis of the mould. Stirring produces a strong fluid flow which results good mixing in the melt. Correspondingly, a homogenized temperature distribution is found in the domain. Because of strong stirring, the solid fraction in the slurry is found to be distributed almost uniformly. It is also found that fragmentation of dendrites increases solid fraction in the slurry with processing time. During processing, the continuous rejection of solute makes the liquid progressively solute enriched. It is predicted from the present study that the remaining liquid surrounding the primary solid phase finally solidifies with a near-eutectic composition, which is desirable from the point of view of semisolid casting. Correspondingly, a set of experiments are performed to validate the numerically predicted results. The numerical predictions of temperature variations are in good agreement with experiments, and the predicted flow field evolution correlate well with the microstructures obtained through experiments at various locations, as observed in the numerical results. Subsequently the study is extended to predict the effect of process parameters such as stirring intensity and cooling rate on the distributions of solid fraction and solute in the domain. It is found, from the simulation, that the solidification process is significantly affected by stirring intensity. At increasing primary excitation current, the magnitude of Lorentz force increases and results in increase of slurry velocity. Correspondingly, the fragmentation of dendrites from the solid/liquid is more during solidification at higher stirring intensity, which increases the fraction of solid in the slurry to a high value. It is also found that the solute and fraction of solid in the liquid mixes well under stirring action. Thus, a near uniform distribution of solute and solid fraction is found in the domain. It is found that stirring at high currents produces high solid fraction in the liquid. Also, at very low cooling rate, the solid fraction in the liquid increases. The present study focuses on the model development and experimental validation for solidification with linear electromagnetic stirring for producing a rheocast billet. Further studies highlighting the effects of various process parameters on the thermal history and microstructure formation are also presented.

The mechanical properties achieved with high performance wrought aluminium alloys are superior to cast aluminum alloys. To obtain an intricate shaped component, wrought alloys are commonly subjected to forging followed by subsequent machining operation in the automobile industry. As machining of such high strength wrought aluminium alloys adds to cost, productivity gets affected. Shortening the process by near net shaped casting would tremendously enhance productivity. However, casting of such alloys frequently encounter hot tear defect. Therefore, circumventing hot tear to successfully die cast near net shaped wrought alloy components is industrially relevant. A recent advanced casting process, namely ‘Semisolid Die casting’, is proposed as a likely solution. Hot tearing originates due to lack of liquid flow in the inter-dendritic region. To reduce hot tear susceptibility, fine and non-dendritic grain structure is targeted, amenable for processing by semisolid route. For semisolid processing an adequate freezing range for processing is required. Accordingly A6061 wrought alloy whose composition is tuned with higher silicon and magnesium content within the grade limits, is chosen for the study. With the objective of obtaining fine and non-dendritic microstructured billets, electromagnetic stirring (EMS) and cooling slope (CS) methods are employed. On conducting a parametric study with EMS, a finest possible primary α-Al grain size of about 70 μm is obtained at low stirring time at stirring current levels of 175 A and 350 A, with the addition of grain refiner. CS, on the other hand, rendered a grain of 60 μm at a slope length of 300 mm at a slope angle of 45° with grain refiner addition. Of the two methods, CS billets are chosen for subsequent induction heating. A 3-step induction heating cycle has been devised to attain a temperature of 641°C in the billet on the basis of factors including coherency point, viscosity of the slurry and solid fraction sensitivity with temperature. The billet microstructure is found to be homogenous throughout after quenching in water. The characterization of phase along primary α-Al grain boundary and its composition analysis is done by SEM and EPMA respectively, after billet casting as well as induction heating. In addition, the bulk hardness is determined in BHN. The induction heated billets are semisolid die cast to produce an engine connecting rod used in automobiles. The microstructure is characterized at various locations, and is found to consist of smooth α-Al grains in a background matrix of fine grains formed due to secondary solidification. The component hardness is found to be 66 BHN comparable with A6061 alloy under T4 heat treated condition. X-ray radiography does not confirm presence of surface hot tear, which is the normal defect associated with casting of wrought aluminium alloys. No defects are observed along the constant cross-sectional area of the connecting rod, suggesting that the processing could be suitable for semisolid extrusion.

Dažniausiai natūralios kosmetikos gaminių sudėtyje tik veikliosios medžiagos yra gamtinės kilmės, todėl aktualu pagaminti kosmetinio preparato pagrindą, panaudojant tik gamtinės kilmės medžiagas. Darbo tikslas: Pagaminti pusiau kietą hidrofobinį pagrindą, panaudojant tik gamtinės kilmės medžiagas ir įvertinti jo kokybę. Metodai: Sistemos gaminamos sulydymo metodu. Jų kokybė vertinama: 1. Dinaminės klampos nustatymu. Vertinamas sistemos kietumas ir stabilumas 2. pH reikšmės nustatymu. 3. Reologinių charakteristikų nustatymu. Vertinamas tepumas ir struktūros stabilumas 4. Mikrostruktūros nustatymu. Vertinamas vienalytiškumas 5. Stabilumo tyrimais. Atliekama natūraliomis sąlygomis 12 mėnesių laikotarpyje. 6. Juslinių savybių tyrimais. Vertinama spalva, kvapas, konsistencija, tepumas ir riebumas. Rezultatai: Nustatyta, kad bičių vaško ir alyvuogių aliejaus pagrindas neužtikrina stabilios sistemos suformavimo, todėl įterptos pagalbinės medžiagos – kakavos sviestas, cholesterolis, baltasis vazelinas ir kietasis parafinas, kurie pagerina juslines savybes ir suformuoja puskietę sistemą. Taikant ortogonalų statistinį planą suformuotos optimizavimo sudėtys, kurioms atlikti mikrostruktūros nustatymo ir reologinių savybių tyrimai. Nustatyta, kad visos sistemos yra vienalytės. Bičių vaškas daro įtaką takumo indekso mažėjimui, konsistencijos koeficiento ir ribinio takumo didėjimui. Kylant temperatūrai preparatų plastinės savybės mažėja. Juslinių savybių tyrimo metu nustatyta, kad... [toliau žr. visą tekstą] / In many of natural cosmetic products only active ingredients are natural therefore it is important to make basis of cosmetic product using only natural substances Purpose of work: To make semisolid hydrophobic basis, designed for lip care using only natural substances and evaluate its quality. Methods: All systems were made by melting. Their quality was assessed: 1. Measurement of dynamic viscosity. Rigidity and stability of systems are evaluated. 2. Measurement of pH value. 3. Measurement of rheological characteristics. Structure stability and lubrication are evaluated. 4. Measurement of microstructure. Homogeneity is evaluated. 5. Test of stability. Stability was studied 12 months in natural conditions. 6. Test of organoleptic characteristics. Color, odor, consistence, lubrication and fatness were evaluated. Results: It has been discovered that the basis of beeswax and olive oil did not form stable structure, therefore were added – cocoa butter, cholesterol, white Vaseline and hard paraffin, which improved organoleptic characteristics and form semisolid system. Compositions for optimization were formed by orthogonal statistical plan. The tests of rheological characteristics and microstructure were made for these compositions. It has been found that all the systems are homogeneous. Beeswax influences the decrease of flow behavior index, and the increase of consistency coefficient and yield stress. With increase of temperature, plasticity of preparations is decreasing Test... [to full text]

As infecções causadas pelo Herpes simplex virus, tipo 1 e 2 (HSV-1 e HSV-2) são consideradas problema de saúde pública no mundo, com prevalência em dois terços da população mundial. A doença é caracterizada pelo aparecimento de vesículas que ocasionam dor e constrangimento ao portador, devido à aparência desagradável que apresentam. As infecções que levam a lesões orofaciais são geralmente ocasionadas pelo HSV-1, enquanto as genitais, pelo HSV-2. O tratamento de escolha baseia-se no uso de antivirais em géis ou pomadas, entretanto, recidivas são comuns e dependentes do estado imunológico do indivíduo, além de exposição a fatores hormonais ou ambientais. Os anestésicos locais diminuem a dor ocasionada pela lesão além de mostrarem ter propriedades antivirais. A forma semissólida facilita a aplicação e a sua transformação em uma película fina, após curto período de tempo, favorece a manutenção da formulação no local, com aspecto final mais discreto quando comparada às opções disponíveis. O objetivo desse trabalho foi desenvolver e avaliar in vitro e in vivo formulações contendo anestésicos para o tratamento do herpes labial. Para tanto, duas formulações semissólidas formadoras de filme foram desenvolvidas e avaliadas (F1 e F1T), contendo HPMC K100, lidocaína (LIDO) e prilocaína (PRILO) combinados a adjuvantes, na presença (F1T) ou não (F1) do promotor de absorção Transcutol®. A mistura de PRILO e LIDO acarretou na formação de uma mistura eutética (ME). Para quantificação dos fármacos a partir da formulação, um método analítico por CLAE (Cromatografia Líquida de Alta Eficiência) foi revalidado e atendeu aos parâmetros preconizados na literatura. A recuperação dos fármacos a partir da pele suína foi satisfatória. As formulações apresentaram homogeneidade na distribuição do conteúdo. A formação do filme in situ foi avaliada e ocorreu em aproximadamente 20 minutos. A adição do promotor de absorção aumentou a concentração dos fármacos no líquido receptor no experimento de permeação passiva in vitro, utilizando pele de orelha suína. E a quantidade de PRILO e LIDO quantificada no estrato córneo foi maior para a formulação sem o Transcutol®. As análises reológicas de cisalhamento contínuo e oscilatório classificaram as formulações como fluídos newtonianos e a F1T apresentou maior estruturação em relação a F1. A avaliação in vitro da multiplicação viral sugere atividade virucida para ambos os fármacos, com proteção a infecção superior a 80% para as concentrações de fármaco avaliadas. As formulações não apresentaram irritação dérmica ao exame macroscópico. O teste in vivo de eficácia comprovou a capacidade dos anestésicos em regredir as lesões causadas por HSV-1. Sendo assim, as formulações propostas mostraram-se boas alternativas ao tratamento de lesões labiais causadas pelo HSV-1. Análises estatísticas adequadas foram realizadas. / Infections by Herpes Simplex virus, type 1 and 2 (HSV 1 e HSV-2) are a public health problem in the world with prevalence of two thirds of the mundial population. This disease is characterized by painful vesicles and embarrassment because of wound appearance. Orofacial wounds are mostly caused by HSV-1 and genital wounds are by HSV-2. Nowadays, current treatment is based on the use of antiviral in cream and ointments but, recurrences are very common and depend of individual state of immunological system besides environmental factors. Topical anesthetics minimize the pain and have shown antiviral properties. The semisolid composition improves application and its transformation into a thin film, after a short period of time, favors the maintenance at the site with good final aspect compared to the currently available treatment options. In this research, we developed and evaluated in vitro and in vivo compositions containing topical anesthetics for treatment of labials herpes. The compositions were prepared using HPMC K100, lidocaine (LIDO) and prilocaine (PRILO) combined with adjuvants, with permeation promoter Transcutol® (F1T) or not (F1). The mix of PRILO and LIDO results in eutectic mixture. For quantified drugs in compositions an analytical method by HPLC (High Performance Liquid Chromatography) was revalidated with satisfactory parameters, as well the recovery of drug on porcine skin. The formulations were with homogeneous content and film formation occurs in approximately 20 minutes. The addition of Transcutol® results in more PRILO and LIDO in receptor medium for F1T at in vitro passive permeation study. The quantify of drugs in corneum layer is mayor in F1 than F1T. Rheological analyses shown the compositions are newtonians fluids and F1T has more cohesion than F1. Evaluation of in vitro viral multiplication suggests activity before virus infects host cells, with 80% of protection of infection for evaluated concentrations. None composition shown dermal irritation in macroscopical examination. The in vivo efficacy study proves the anesthetics capacity of regress the HSV-1 wounds. Therefore, the developed compositions are good alternatives for labialis herpes caused by HSV-1.

"Semi-solid metal (SSM) processing has emerged as a preferred manufacturing method due to the superior quality associated with semi-solid castings. In recent years, the driving force to reduce process cost has led to the development of a few rheocasting (also termed slurry-on-demand) processes. These include UBE’s New Rheocasting (NRC) process [1], Idra Prince’s Semi-Solid Rheocasting (SSR) process [2], and THT’s Sub-Liquidus Casting (SLC®) process [3]. A novel slurry-making SSM process developed at ACRC/MPI, termed the “Continuous Rheoconversion Process” (CRP), is a passive liquid mixing technique in which the nucleation and growth of the primary phase are controlled using a specially designed “reactor”. The reactor provides heat extraction, copious nucleation and forced convection during the initial stage of solidification, leading to the formation of thixotropic structures. In these studies, the critical issues/challenges to optimize the CRP for industrial applications have been addressed through validation experiments and pre-industrial trials."

Emulsijos yra patrauklios išvaizdos, universalūs produktai, jų naudojimas yra paprastas bei priimtinas, dėl to jos yra ypač dažnai sutinkamos dermatologijoje, gydant įvairias odos ligas. Stabilus puskietis emulsinis pagrindas iš natūralių medžiagų yra aktualus, nes turi dideles pritaikymo galimybes kosmetinių ir gydomųjų kremų gamyboje. Tyrimo objektas – puskietė emulsinė sistema vanduo aliejuje iš natūralių medžiagų su bičių vašku, kaip vaistinių medžiagų nešiklis dermatologiniams preparatams. Darbo tikslas – puskietės emulsinės sistemos vanduo aliejuje (v/a) su bičių vašku sumodeliavimas ir modelinės medžiagos – askorbo rūgšties atpalaidavimo iš sumodeliuotos sistemos įvertinimas biofarmaciniu in vitro tyrimu. Tyrimo uždaviniai: parinkti puskietės emulsinės sistemos sudėtį, remiantis ortogonaliu statistiniu planu, ir atrinkti stabilius pavyzdžius pagal pasirinktus vertinimo kriterijus (tinkamas pH, klampa, mikrostruktūra bei juslinės savybės); nustatyti puskiečių emulsinių sistemų fizikocheminius rodiklius (pH, klampą, mikrostruktūrą) bei įvertinti jų stabilumą po 1 ir 3 mėn.; įvertinti bičių vaško įtaką puskiečių emulsinių sistemų klampai, stabilumui, juslinėms savybėms bei askorbo rūgšties atpalaidavimui iš puskietės emulsinės sistemos; įvertinti modelinės medžiagos – askorbo rūgšties atpalaidavimą iš tiriamų puskiečių emulsinių sistemų, atliekant biofarmacinį tyrimą in vitro per pusiau pralaidžią membraną; atlikti emulsinės sistemos juslinių savybių ir kokybės... [toliau žr. visą tekstą] / Emulsion has an attractive conformation and is an universal product. It‘s usage is simple and acceptable. For this reason, it is often used in dermatology for curing different skin disease. Stable semisolid emulsion base from natural materials is relevant because it has a big variety of use in cosmetic and remedial cream production. The object of research – the system of semisolid emulsion water in oil from natural materials and beeswax as a carrier of medical materials in dermatological preparations. The aim of the work – modeling the system of semisolid emulsion water in oil with the beeswax and modeling materials as liberation ascorbic acid from simulated system and it‘s biopharmacy evaluation by in vitro research. The task of research: to choose the composition of semisolid emulsion system on the ground of orthogonal statistic plan and select stable samples according to evaluation criterion (the proper pH, viscosity, microstructure and organoleptic properties); to rate physicochemical rates of the system of semisolid emulsion (pH, viscosity, microstructure) and evaluate their stability after 1 and 3 months; to evaluate the influence of beeswax on the viscosity, stability, sensual properties and the liberation of ascorbic acid from the system of semisolid emulsion; to evaluate modeling materials – the liberation of ascorbic acid from investigative system of semisolid emulsion carrying out biopharmacy research in vitro through semi-permeable membrane; to evaluate sensual... [to full text]

Made available in DSpace on 2018-06-27T18:56:38Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-04-19 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Acne vulgaris is a genetic hormone disease, located in the hair follicle. Adapalene a third-generation retinoid, and it is a topical alternative for acne treatment, but may have some adverse effects, irritation and dryness of the skin are the most common. Due to this, and knowing the nanocarriers potential, the object of this study was determine the physicochemical stability of semisolid formulations containing adapalene-loaded nanocapsules (NC) incorporated in Aristoflex AVL®, evaluate the release profiles in semisolid formulations containing nanocapsules containing adapalene incorporated in Carbopol 940® and verify the safety of the formulation in vivo by noninvasive biophysical analysis. For the determination of the stability, samples were subjected to freeze-thaw cycle, completing a cycle of 21 days. The in vitro release studies were performed comparing the drug-loaded NC (GCNCA) with the gel containing adapalene in its free form (GCA). For the skin bioengineer techniques, twenty healthy volunteers were selected. Each week were performed biometric skin tests including stratum corneum water content (hydration), pH, color, erythema and transepidermal water loss for 63 days. In stability studies, we observed that the average particle size, polydispersity and zeta potential of cream gel containing NC without adapalene (CGNC) and cream gel containing adapaleneloaded NC (CGNCA) showed no change after being subjected to the freeze-thaw cycle. Semisolid formulations showed non-Newtonian flow and pseudoplastic behavior during the study period. The initial adapalene content in CGNCA did not change compared with the result obtained at the end of the experiment. However, for the cream gel containing free adapalene (CGA), there was a reduction in the drug concentration, whereas the initial content decreased to below 90% after 21 days of analysis. According to release studies, we can observe that the GCNCA showed total concentration and release rate less than the GCA, which demonstrates the ability of nanoparticles to control the drug release. According to the results observed for the non-invasive method in relation to the determination of melanin content, there was a decrease in this parameter during the experiment for both formulations. The GCNCA did not cause erythema, configuring security in the use of the formulation. However, the GCA increased the index of erythema of the skin of volunteers. We observed an increase in transepidermal water loss to the GCA while in GCNCA there is a reduction of this parameter. The results obtained for skin hydration, there was a more pronounced reduction of the values of the stratum corneum water content in the treated areas with GCA. Thus, it was evident that the polymeric nanocapsules are able to decrease transepidermal water loss, favoring the skin hydration degree and keeping the stratum corneum integrity. / A acne vulgar é uma doença genética hormonal, de localização pilo-sebácea. O adapaleno, retinóide de terceira geração, é uma alternativa tópica para o tratamento da acne, podendo apresentar alguns efeitos indesejáveis, sendo a irritação e o ressecamento da pele os mais comuns. Em vista disso, e conhecendo as potencialidades dos nanocarreadores, o presente trabalho tem como objetivo determinar a estabilidade físico-química de formulações semissólidas contendo adapaleno nanoestruturado incorporado em Aristoflex AVL®, avaliar os perfis de liberação em formulações semissólidas contendo nanocápsulas (NC) de adapaleno incorporadas em Carbopol 940® e verificar a segurança do fármaco nanoencapsulado in vivo, através de análises biofísicas não invasivas. Para a determinação da estabilidade as amostras foram submetidas ao ciclo gelo-degelo, completando-se um ciclo de 21 dias. Os estudos de liberação in vitro foram realizados comparando-se as formulações contendo nanocápsulas de adapaleno (GCNCA) com o gel contendo o fármaco na forma livre (GCA). Para o ensaio utilizando biometria cutânea, foram selecionados vinte voluntários saudáveis. A cada semana foram realizados testes de bioengenharia cutânea, incluindo avaliação do conteúdo aquoso do estrato córneo (hidratação), pH, coloração, eritema e perda transepidérmica de água durante 63 dias. Nos estudos de estabilidade, observou-se que o diâmetro médio das partículas, índice de polidispersão e potencial zeta do creme gel contendo NC sem adapaleno (CGNC) e do creme gel contendo NC de adapaleno (CGNCA) não apresentaram alterações após serem submetidos ao ciclo gelodegelo. As formulações semissólidas independente da forma de dispersão do fármaco apresentaram fluxo não-newtoniano e comportamento pseudoplástico durante todo o período de análise. O teor inicial de adapaleno no CGNCA não sofreu alteração, quando comparado com o teor obtido no término do experimento. Entretanto, para o creme gel contendo adapaleno livre (CGA) houve uma redução na concentração de adapaleno, visto que o teor inicial decaiu para valores abaixo de 90% após 21 dias de análise. Com relação aos estudos de liberação, pode-se observar que o GCNCA apresentou concentração total e taxa de liberação menor do que o GCA, o que demonstra a capacidade das nanopartículas em controlar a liberação do fármaco. De acordo com os resultados observados para o ensaio de bioengenharia cutânea, com relação à determinação do conteúdo de melanina, verificouse uma redução deste parâmetro no decorrer do experimento para ambas as formulações. O GCNCA não causou eritema, configurando a segurança na utilização da formulação. Entretanto, o GCA aumentou, de maneira estatisticamente significativa, o índice de eritema da pele dos voluntários. Foi observado um aumento na perda transepidérmica de água para o GCA enquanto no GCNCA observa-se uma redução deste parâmetro. Nos resultados obtidos para hidratação cutânea, observou-se uma redução mais pronunciada dos valores do conteúdo aquoso do estrato córneo nas regiões tratadas com GCA. Desta forma, evidenciou-se que as nanocápsulas poliméricas são capazes de diminuir a perda transepidérmica de água, favorecendo o grau de hidratação cutânea e mantendo a integridade do estrato córneo.

Submitted by MARCIA ROVADOSCHI (marciar@unifra.br) on 2018-08-16T13:49:23Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertacao_GabrielaD'AvilaFarias.pdf: 1690913 bytes, checksum: 045532806a12d78ce1324029cd8aedaf (MD5) / Made available in DSpace on 2018-08-16T13:49:23Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertacao_GabrielaD'AvilaFarias.pdf: 1690913 bytes, checksum: 045532806a12d78ce1324029cd8aedaf (MD5) Previous issue date: 2011-04-19 / Acne vulgaris is a genetic hormone disease, located in the hair follicle. Adapalene a third-generation retinoid, and it is a topical alternative for acne treatment, but may have some adverse effects, irritation and dryness of the skin are the most common. Due to this, and knowing the nanocarriers potential, the object of this study was determine the physicochemical stability of semisolid formulations containing adapalene-loaded nanocapsules (NC) incorporated in Aristoflex AVL®, evaluate the release profiles in semisolid formulations containing nanocapsules containing adapalene incorporated in Carbopol 940® and verify the safety of the formulation in vivo by noninvasive biophysical analysis. For the determination of the stability, samples were subjected to freeze-thaw cycle, completing a cycle of 21 days. The in vitro release studies were performed comparing the drug-loaded NC (GCNCA) with the gel containing adapalene in its free form (GCA). For the skin bioengineer techniques, twenty healthy volunteers were selected. Each week were performed biometric skin tests including stratum corneum water content (hydration), pH, color, erythema and transepidermal water loss for 63 days. In stability studies, we observed that the average particle size, polydispersity and zeta potential of cream gel containing NC without adapalene (CGNC) and cream gel containing adapaleneloaded NC (CGNCA) showed no change after being subjected to the freeze-thaw cycle. Semisolid formulations showed non-Newtonian flow and pseudoplastic behavior during the study period. The initial adapalene content in CGNCA did not change compared with the result obtained at the end of the experiment. However, for the cream gel containing free adapalene (CGA), there was a reduction in the drug concentration, whereas the initial content decreased to below 90% after 21 days of analysis. According to release studies, we can observe that the GCNCA showed total concentration and release rate less than the GCA, which demonstrates the ability of nanoparticles to control the drug release. According to the results observed for the non-invasive method in relation to the determination of melanin content, there was a decrease in this parameter during the experiment for both formulations. The GCNCA did not cause erythema, configuring security in the use of the formulation. However, the GCA increased the index of erythema of the skin of volunteers. We observed an increase in transepidermal water loss to the GCA while in GCNCA there is a reduction of this parameter. The results obtained for skin hydration, there was a more pronounced reduction of the values of the stratum corneum water content in the treated areas with GCA. Thus, it was evident that the polymeric nanocapsules are able to decrease transepidermal water loss, favoring the skin hydration degree and keeping the stratum corneum integrity. / A acne vulgar é uma doença genética hormonal, de localização pilo-sebácea. O adapaleno, retinóide de terceira geração, é uma alternativa tópica para o tratamento da acne, podendo apresentar alguns efeitos indesejáveis, sendo a irritação e o ressecamento da pele os mais comuns. Em vista disso, e conhecendo as potencialidades dos nanocarreadores, o presente trabalho tem como objetivo determinar a estabilidade físico-química de formulações semissólidas contendo adapaleno nanoestruturado incorporado em Aristoflex AVL®, avaliar os perfis de liberação em formulações semissólidas contendo nanocápsulas (NC) de adapaleno incorporadas em Carbopol 940® e verificar a segurança do fármaco nanoencapsulado in vivo, através de análises biofísicas não invasivas. Para a determinação da estabilidade as amostras foram submetidas ao ciclo gelo-degelo, completando-se um ciclo de 21 dias. Os estudos de liberação in vitro foram realizados comparando-se as formulações contendo nanocápsulas de adapaleno (GCNCA) com o gel contendo o fármaco na forma livre (GCA). Para o ensaio utilizando biometria cutânea, foram selecionados vinte voluntários saudáveis. A cada semana foram realizados testes de bioengenharia cutânea, incluindo avaliação do conteúdo aquoso do estrato córneo (hidratação), pH, coloração, eritema e perda transepidérmica de água durante 63 dias. Nos estudos de estabilidade, observou-se que o diâmetro médio das partículas, índice de polidispersão e potencial zeta do creme gel contendo NC sem adapaleno (CGNC) e do creme gel contendo NC de adapaleno (CGNCA) não apresentaram alterações após serem submetidos ao ciclo gelodegelo. As formulações semissólidas independente da forma de dispersão do fármaco apresentaram fluxo não-newtoniano e comportamento pseudoplástico durante todo o período de análise. O teor inicial de adapaleno no CGNCA não sofreu alteração, quando comparado com o teor obtido no término do experimento. Entretanto, para o creme gel contendo adapaleno livre (CGA) houve uma redução na concentração de adapaleno, visto que o teor inicial decaiu para valores abaixo de 90% após 21 dias de análise. Com relação aos estudos de liberação, pode-se observar que o GCNCA apresentou concentração total e taxa de liberação menor do que o GCA, o que demonstra a capacidade das nanopartículas em controlar a liberação do fármaco. De acordo com os resultados observados para o ensaio de bioengenharia cutânea, com relação à determinação do conteúdo de melanina, verificouse uma redução deste parâmetro no decorrer do experimento para ambas as formulações. O GCNCA não causou eritema, configurando a segurança na utilização da formulação. Entretanto, o GCA aumentou, de maneira estatisticamente significativa, o índice de eritema da pele dos voluntários. Foi observado um aumento na perda transepidérmica de água para o GCA enquanto no GCNCA observa-se uma redução deste parâmetro. Nos resultados obtidos para hidratação cutânea, observou-se uma redução mais pronunciada dos valores do conteúdo aquoso do estrato córneo nas regiões tratadas com GCA. Desta forma, evidenciou-se que as nanocápsulas poliméricas são capazes de diminuir a perda transepidérmica de água, favorecendo o grau de hidratação cutânea e mantendo a integridade do estrato córneo.

Tyrimo tikslas: sumodeliuoti puskietes sistemas su bičių produktais ir įvertinti jų kokybę biofarmaciniais tyrimais. Uždaviniai: 1. Atrinkti tinkamą propolio, kaip veikliosios medžiagos, formą įvedimui į modeliuojamas puskietes sistemas; 2. Pagaminti stabilias puskietes formas su bičių produktais (bičių vašku, propoliu, medumi) ir įvertinti jų kokybę, tiriant šiuos parametrus: vienalytiškumas, pH reikšmė, antioksidacinis aktyvumas; 3. Atlikti puskiečių sistemų su bičių produktais biofarmacinį vertinimą ir identifikuoti veiksnius, darančius įtaką bendro fenolinių junginių kiekio atpalaidavimui; 4. Įvertinti puskiečių formų su bičių produktais kokybę, remiantis atliktais veikliųjų junginių (fenolinių rūgščių, vanilino) atpalaidavimo in vitro tyrimo rezultatais. Bičių produktų puskiečių sistemų analizei pasirinktas fenolinių junginių nustatymas spektrofotometriniu ir ESC metodais bei spektrofotometrinis metodas laisvųjų DPPH• radikalų surišimo aktyvumui pagal troloksą nustatyti. Vaisto formų kokybė vertinta nustatant pH reikšmę ir atliekant veikliųjų junginių atpalaidavimo tyrimą in vitro. Į puskietes sistemas veiklioji medžiaga (propolis) įterpiama tirštojo arba skystojo (gelyje) ekstrakto forma. Stabilios I grupės sistemos pagaminamos tada, kai bičių vaško ir saulėgrąžų aliejaus santykis ne didesnis kaip 1:5. Bičių vaškas ir medus daro įtaką atpalaiduojamam veikliųjų junginių kiekiui – didėjant vaško kiekiui, veikliųjų junginių iš sistemų atsipalaiduoja mažesnis kiekis, o iš... [toliau žr. visą tekstą] / The aim of work: Formulate and analyze semisolid preparations with bees products and evaluate their quality by biopharmaceutical researches. Main tasks: 1. Select the proper form of propolis as an active material in formulated semisolid systems; 2. Formulate stable semisolid systems with bees products (beeswax, propolis, honey) and evaluate their quality by investigation of these parameters: homogenity, pH value, antioxidant activity; 3. Perform biopharmaceutical evaluation of semisolid systems with bees products and identify the factors that influence release the total amount of phenolic compounds; 4. Evaluate quality of semisolid systems with bees products based on active compounds (phenolic acids, vanillin) in vitro release test results. Semisolid systems with bees products are analyzed by using spectrophotometric and capillary HPLC methods for analysis of total phenolic compounds measuring, DPPH• free radical scavenging activity measuring according to trolox. Quality of the systems was evaluated by measuring pH values and by testing release of active compounds in vitro. The active substance propolis is inserted into semisolid systems by thick or liquid (in gels) extract form. Stable system of the Group I semisolid systems is formulated when beeswax and sunflower oil ratio is less than 1:5. Beeswax and honey in systems affect the release of active compounds - increasing the wax content, the active compounds release of the systems is reduced, adequate quantity of honey... [to full text]

Submitted by Maria Medeiros (maria.dilva1@ufcg.edu.br) on 2018-09-12T13:53:26Z No. of bitstreams: 1 MARINÉVEA MEDEIROS OLIVEIRA - TESE (PPGEP) 2007.pdf: 931472 bytes, checksum: 7310439f122abecc70aef47891f5f784 (MD5) / Made available in DSpace on 2018-09-12T13:53:26Z (GMT). No. of bitstreams: 1 MARINÉVEA MEDEIROS OLIVEIRA - TESE (PPGEP) 2007.pdf: 931472 bytes, checksum: 7310439f122abecc70aef47891f5f784 (MD5) Previous issue date: 2007-05-03 / O Brasil é um dos principais produtores mundial de abacaxi e maracujá, com uma grande quantidade de resíduos desperdiçados que já se tornou um sério problema aos produtores de abacaxi e maracujá e as indústrias de alimentos em geral. Em países desenvolvidos, a produção agropecuária se caracteriza com baixos custos operacionais, em razão das utilizações de restos de culturas e de resíduos agroindustriais como alternativas na alimentação animal, contribuindo para minimizarem os problemas de poluição. O objetivo deste trabalho foi definir ações no campo da pesquisa na alimentação alternativa nutricional para animais , de modo a realizar o aproveitamento destes resíduos enriquecidos nutricionalmente (protéico, vitamínico, mineral e energético) utilizando a levedura Saccharomyces cerevisiae como agente da metabolização, de uma maneira tecnicamente viável, visando a disponibilidade do produto, para os produtores. Foram feitas as isotermas de dessorção dos resíduos em estudo, nas temperaturas usuais dos processos das fermentações, 25, 30, 35 e 40 0C, ajustando os dados através da aplicação de modelos matemáticos, e verificou-se que, deve-se iniciar o processo de fermentação com umidade inicial do substrato para os três resíduos acima de 84% (b.u.), o que equivale a atividade de água acima de 0,90. No estudo cinético verificou-se que o melhor tempo em que o microrganismo atingiu o maior teor de proteína bruta foi, em média, de 48 h, para todos os resíduos analisados. Utilizou-se a metodologia de planejamento fatorial mais configuração estrela para estudar as influências das variáveis de entrada sobre o processo de enriquecimento nutricional dos resíduos casca de abacaxi (Caa), coroa de abacaxi (Coa) e casca de maracujá (Cam), com concentrações de leveduras de 1, 3 e 5% e temperaturas de 30, 34 e 38 oC. Fez-se o planejamento fatorial mais configuração estrela para os três resíduos, com duas variáveis de saída (respostas: teor de proteína bruta e teor de aumento protéico). O aumento protéico (AP) encontrado para os três resíduos analisados, foi em média de 2,40 vezes em relação ao in natura. Os valores otimizados dos três resíduos casca de abacaxi (Caa), coroa de abacaxi (Coa) e casca de maracujá (Cam) (concentração Oliveira M.M.de 14 em torno de 3 – 5,8% e temperaturas de 34 – 40 oC), no tempo de 48 h, visando baratear os custos do enriquecimento e obter um teor de proteína adequado na alimentação animal foram de 24,66, 23,88 e 22,74%, respectivamente. Foram realizadas as análises de proteína bruta (PB), matéria seca (MS), cinzas (MM), matéria orgânica (MO), fósforo (P), cálcio (Ca), magnésio (Mg), potássio (K), fibra detergente neutra (FDN), fibra detergente ácida (FDA), energia bruta (EB) e digestibilidade “in vitro” (DIVMS in vitro) nos resíduos operando com as variáveis de entrada (concentração de levedura e temperatura) com valores otimizados. Conclui-se que através da bioconversão, os resíduos alcançam concentrações nutricionais que, podem ser transformados em suplemento nutricional, sendo uma alternativa alimentar para os animais, na época de escassez de alimento no semiárido. / Brazil stands out among the big world-wide producers of pineapple (Ananas comosus L. Mer) and passion fruit (Passiflora edulis Sims), with a great amount of wasted residues, which has become a serious problem for the pineapple and passion fruit producers and the aliment industries in general. In developed countries, the farming production is characterized by low operational costs, because of the use of the remaining portions of cultures and agro-industrial residues as an alternative in animal feed, which also contributes to minimizing pollution problems. The aim of this work was to define actions in the field of research of nutritional alternative feed for animals, in order to carry through the exploitation of these nutritionally enriched (protein, vitamin, mineral and energy) residues by using Saccharomyces cerevisiae yeast as an agent of metabolism, in a technical viable way, aiming at the availability of the product to the producers. Desorption isotherms of the residues in study were done at the usual temperatures of fermentation processes, 25, 30, 35 and 40 oC, fitting the data through the application of mathematical models, and it was verified that the process of fermentation must be initiated with the initial moisture content of the substratum for the three residues above of 84% (w.b), which is equivalent to the water activity above of 0.90. In the kinetic study it was verified that optimum time where the microorganism reached the highest content was, on average, 48 hours, for all the residues analyzed. Methodology of factorial design plus configuration star was used to study the influences of the entrance variable on the process of nutritional enrichment of the residues of pineapple rind (PR), crown of pineapple (CP) and rind of passion fruit (PF), with concentrations of yeast at 1, 3 and 5% and temperatures of 30, 34 and 38 °C. The factorial design plus configuration star was performed for the three residues, with two exit variables (response: gross protein content and protein increase content). The protein increase content (PI) found for the three analyzed residues was on average of 2.40 times in relation to in natura. The optimized values of the three residues of pineapple rind (PR), crown of pineapple (CP) and passion fruit rind (PFR) (concentration around 3-5.8% and Oliveira M.M.de 16 temperatures of 34-40 °C), in the time of 48 hours, aiming to lower the costs of the enrichment and to obtain an adequate protein content in the animal feed were of; 24.66, 23.88 and 22.74%, respectively. Gross protein (GP), dry substance (DS), leached ashes (LA), organic substance (OG), phosphorus (P), calcium (Ca), magnesium (Mg), potassium (K), fiber neutral detergent (FND), acid fiber detergent (AFD), rude energy (RE) and digestibility in vitro (DIVMS in vitro) analysis were performed in the residues, operating with the entrance variables (concentration of yeast and temperature) with optimized values. It can be concluded that through bioconversion, the residues reach nutritional concentrations that can be transformed into a nutritional supplement alternative, being an option to feed animals at times of food scarcity in semi-arid climates.