Avaliação do potencial da Telemedicina em Cuidados Paliativos no câncer avançado

Este estudo avaliou o potencial da Telemedicina como suporte complementar a assistência ambulatorial na monitoração de sintomas em pacientes com câncer avançado. Foram acompanhados 12 pacientes do ambulatório do Núcleo de Cuidados Paliativos do Hospital Universitário Pedro Ernesto (NCP-HUPE) de janeiro de 2011 a agosto de 2013. Mensalmente foram feitas consultas ambulatoriais pela médica e equipe multidisciplinar. Neste intervalo, os pacientes do domicilio, através de seus computadores pessoais se conectaram ao Laboratório de TeleSSaúde UERJ pelo serviço de webconferências interagindo com a mesma médica assistente do ambulatório. Os pacientes também tiveram acesso à médica por celular e email. A cada entrevista (presencial e remota) foi aplicada a Escala de Avaliação de Sintomas de Edmonton [Edmonton Symptom Assessment System (ESAS)], e coletado outros dados quanto a outras queixas biopsicossociais e espirituais, agravos à saúde, qualidade de áudio e vídeo da conexão, avaliação dos familiares com a Telemedicina e interferência da Telemedicina quanto ao local do óbito do paciente. Houve dificuldade na seleção dos pacientes, pois o HUPE é um hospital público cuja população assistida tem, caracteristicamente, baixa escolaridade, nível socioeconômico restrito e pouca habilidade com informática. O tempo médio de acompanhamento foi de 195 dias (DP 175,11; range: 11-553 dias). Todos receberam diagnóstico de câncer avançado e tinham dificuldades com locomoção. Sem dúvidas, a ESAS favoreceu a comunicação dos sintomas com os profissionais de saúde; porém, condições clínicas e controle dos sintomas singulares, avaliados em momentos distintos e sujeitos a influências diversas, impedem conclusões em relação às pretensas vantagens. Acompanhamento clínico, detecção de agravos à saúde e de sintomas físicos, psicossociais e espirituais foram possíveis de ser observados pela Telemedicina, confirmados e medicados nas consultas presenciais. A conexão para webconferência foi estabelecida por familiares, pois nenhum paciente operava computadores. O óbito domiciliar ocorreu em 41,67% e todos, mesmo os óbitos hospitalares, receberam suporte à distância do NCP. Durante o estudo foram feitos 305 contatos: 110 consultas presenciais a pacientes e familiares e 195 por Telemedicina (77 webconferências, 38 telefonemas e 80 emails). Todos os familiares referiram satisfação com o suporte oferecido. A Telemedicina permitiu maior acesso ao sistema de saúde (maior número de contatos), reduziu a busca por serviços de emergência, ajudou o controle dos sintomas e proporcionou orientações e segurança aos familiares. Este suporte favoreceu intervenções precoces e proativas e assistência continuada até o óbito. A Telemedicina demonstrou ser um bom adjuvante na monitoração e gerenciamento de sintomas de pacientes em cuidados paliativos em domicílio, não substituindo, mas complementando a assistência presencial.

Estudo de aspectos epidemiológicos, clínicos e imunológicos da hanseníase em município hiperendêmico

A epidemiologia da hanseníase tem demonstrado a utilização de ferramentas clínicas, moleculares e imunológicas, para o mapeamento dos principais focos de ocorrência da doenças e de áreas de alto risco de adoecimento. Programas de controle da hanseníase, doença de longo período de incubação, em que os contatos são os principais grupos de risco, devem estabelecer todos os procedimentos disponíveis para o controle desse agravo. Objetiva-se estudar aspectos epidemiológicos clínicos e imunológicos da hanseníase em município hiperendêmico do Maranhão. Estudo de epidemiológico descritivo, realizado com 599 contatos, entre outubro de 2009 a outubro de 2011, no Serviço de Dermatologia no ambulatório do Hospital Universitário da Universidade Federal do Maranhão unidade Presidente Dutra São Luís - MA. Foi observado que a maioria dos contatos foi do gênero feminino com 57,17%, a faixa etária predominante acima de 15 anos, ou seja, (64,59%) com maior frequência na faixa de 20 a 59 anos, idade adulta e produtiva e o tipo de convívio predominante é o intradomiciliar com 74,95%, a forma clínica foi HT (30,00%), a classificação operacional mais frequente foi a MB com 61,90% do gênero feminino; a maioria apresentou somente uma cicatriz vacinal pela BCG, destacou-se o gênero masculino com 63,00%. O teste Elisa apresentou percentual de 63,50% e o ML-Flow 64,00%. Considerando o resultado dos testes Elisa e ML-FLOW sugere-se a utilização das técnicas imunológicas como ferramentas necessárias para o diagnóstico precoce, controle e vigilância dos contatos como forma de interromper a cadeia de transmissão da hanseníase na cidade pesquisada.

Dose terapêutica de radiação ionizante induz um fenótipo migratório em células de carcinoma de colon humano (caco-2): vias de sinalização envolvidas

O câncer colo-retal é a terceira neoplasia mais frequente em todo o mundo e a recorrência local e neoplasia refratária são desafios no tratamento do câncer colo-retal após a cirurgia convencional. Com o intuito de controlar a recorrência e aumentar a média de sobrevida dos pacientes, uma estratégia multidisciplinar que combina a radioterapia (RT) e a quimioterapia com o processo cirúrgico tem sido protocolo clínico de escolha. Embora esta combinação seja capaz de otimizar o tratamento, nem todos os pacientes são beneficiados com o protocolo quimio-rádio combinado, uma vez que existem os insucessos terapêuticos relacionados com a incidência de neoplasias secundárias tardias em pacientes que foram submetidos à RT para tratamento de neoplasias anteriores. Além da doença refratária, outro agravante da RT são os efeitos colaterais produzidos pela radiação ionizante (IR), em especial àqueles do trato gastrointestinal. Estes efeitos estão relacionados com alterações da homeostase do epitélio intestinal, através da desorganização dos complexos juncionais. Porém, os mecanismos que medeiam estes efeitos ainda não estão elucidados. Este estudo avaliou as vias de sinalização que medeiam os efeitos da IR em células Caco-2. Foi observado que a IR causa uma desorganização da junção aderente via Src, EGFR e MAPK, sendo estas alterações acompanhadas por desorganização do citoesqueleto de actina em todo o volume celular. Src, EGFR e MAPK participam de maneira diferenciada na modulação destes efeitos. Observamos também que a radiação aumenta a motilidade dessas células via Src e MAPK e não induz alteração na proliferação celular até 48 horas após o tratamento. Este é o primeiro trabalho que correlaciona vias de sobrevivência celular como Src, EGFR e MAPK com alterações nas proteínas de junção aderente, alterações do citoesqueleto e migração celular. Estes eventos são relacionados aos efeitos colaterais primários e tardios induzidos pela IR, e podem favorecer à aquisição de um fenótipo maligno herdável durante o fracionamento de doses na RT, favorecendo a progressão tumoral do câncer colo-retal. Logo, além da correlação das vias de sinalização envolvidas nos eventos induzidos pela IR mostrados neste estudo, os resultados também corroboram para um melhor entendimento da atividade farmacológica dos inibidores químicos utilizados, uma vez que muitos deles encontram-se em fase de ensaios pré-clínicos e clínicos.

A field effect transistor using highly nitrogen-doped CVD diamond for power device applications

A new idea of power device, which contains highly nitrogen-doped CVD diamond and Schottky contact, is proposed to actualise a power device with diamond. Two-dimensional simulation is conducted using ISE TCAD device simulator. While comparably high current is obtained in a transient simulation as expected, this current does not contribute to the drain-source current because of the symmetry of the device. Using an asymmetric structure or bias conditions, the device has high potential as an electric device for extremely high power, high frequency and high temperature. © 2003 Elsevier Science B.V. All rights reserved.

The generation of wear surfaces

Abrasive wear is likely to occur whenever a hard asperity or a trapped hard particle is dragged across a softer surface, and it has been estimated that this form of wear contributes to as many as half of the wear problems that are met in industry. Such damaging hard particles may be external contaminants, products of corrosion or even the debris from previous wear events. During the life of a component, damage caused by individual asperity or particle interactions builds up and, at each stage of its life, the worn surface is the result of many such superimposed wear events. The practical, quantitative prediction of wear rates depends on having both a satisfactory understanding of individual interactions and a suitable procedure for combining these when subsequent contacts are made on a surface whose topography and material properties may have been much changed Irom their initial states. The paper includes some details of an analytical model for the interaction of a representative asperity and the worn surface which can both predict the frictional force and the balance between ploughing, when material is displaced but not lost from the surface, and micromachining or cutting, when actual detachment occurs. Experiments tö !rvvéSuQ8Î8 the validity of the model have been carried out on a novel wear rig which provides very precise control over the position of the asperity and the counterface. This facility, together with that of on-board profilometry, means that it is possible to carry out wear experiments on areas of the surface whose previous deformation history is well known; in this way it is possible to follow the development of a worn surface in a controlled manner as the damage from individual wear events accumulates. Experimental data on the development of such a surface, produced by repeated parallel abrasion, are compared with the predictions of the model. © 1992 IOP Publishing Ltd.

Potential tuning of porous silicon luminescence

Electrochemical investigations were conducted of the effect of potential on the luminescence of porous silico (PS). The use of liquid contacts allows the potential to be controlled during studies of the photoluminescence (PL) and electroluminescence (EI). The PL and EL of PS samples prepared from n-type substrates is considered. To obtain luminescence from such PS it is necessary to generate holes in the valence band. This is achieved by either photoexcitation or an electrochemical process involving the reduction of persulfate. This paper describes the investigations of the effect of potential on the PL and EL of PS. A mechanism of 'potential tuning' based on electron occupancy and Auger quenching is then proposed.

Friction of sliding surfaces carrying adsorbed lubricant layers

In concentrated contacts the behaviour of lubricants is much modified by the high local pressures: changes can arise both from molecular ordering within the very thin film lubricant layers present at the interface as well as from the deposition on the component surfaces of more solid-like polymeric boundary layers. These 'third bodies' separating the solid surfaces may have rheological or mechanical properties very different from those observed in the bulk. Classical elasto-hydrodynamic theory considers the entrapped lubricant to exhibit a piezo-viscous behaviour while the conventional picture of more solid boundary lubricant layers views their shear strength r as being linearly dependent on local pressure p, so that T = TO + ap where TO and a are constants. If TO is relatively small, then the coefficient of friction \i = T Ip ~ a and so Amonton's laws are recovered. However, the properties of adsorbed or deposited surface films, or indeed other third bodies such as debris layers, may be more complex than this. A preliminary study has looked quantitatively at the influence of the pressure dependence of the shear strength of any surface layer on the overall friction coefficient of a contact which is made up of an array of asperities whose height varies in a Gaussian manner. Individual contact points may be elastic or plastic. The analysis results in plots of coefficient of friction versus the service or load parameter PIH&NRa where P is the nominal pressure on the contact, HS the hardness of the deforming surface, N the asperity density, R the mean radius of curvature of the asperities, and a is the standard deviation of their height distribution. In principle, any variation oft withp can be incorporated into the model; however, in this initial study we have used data on colloidal suspensions from the group at the Ecole Centrale de Lyon as well as examining the effect of functional relationships of somewhat greater complexity than a simple linear form. Results of the analysis indicate that variations in fj. are possible as the load is varied which depend on the statistical spread of behaviour at individual asperity contacts. The value of this analysis is that it attempts to combine the behaviour of films on the molecular scale with the topography of real engineering surfaces and so give an indication of the effects at the full-size or macro-scale that can be achieved by chemical or molecular surface engineering.

Fabrication of an organic field effect transistor using nano imprinting of Ag inks and semiconducting polymers

A simple and cheap procedure for flexible electronics fabrication was demonstrated by imprinting metallic nanoparticles (NPs) on flexible substrates. Silver NPs with an average diameter of 10 nm were prepared via an improved chemical approach and Ag Np ink was produced in α-terpineol with a concentration up to 15%. Silver micro/nanostructures with a dimension varying from nanometres to microns were produced on a flexible substrate (polyimide) by imprinting the as-prepared silver ink. The fine fluidic properties of an Ag NP/α-terpineol solution and low melting temperatures of silver nanoparticles render a low pressure and low temperature procedure, which is well suited for flexible electronics fabrication. The effects of sintering and mechanical bending on the conductivity of imprinted silver contacts were also investigated. Large area organic field effect transistors (OFET) on flexible substrates were fabricated using an imprinted silver electrode and semiconducting polymer. The OFET with silver electrodes imprinted from our prepared oleic acid stabilized Ag nanoparticle ink show an ideal ohmic contact; therefore, the OFET exhibit high performance (Ion/Ioff ratio: 1 × 103; mobility: 0.071 cm2 V-1 s-1). © 2010 IOP Publishing Ltd.

Foot contact detection for sprint training

We introduce a new algorithm to automatically identify the time and pixel location of foot contact events in high speed video of sprinters. We use this information to autonomously synchronise and overlay multiple recorded performances to provide feedback to athletes and coaches during their training sessions. The algorithm exploits the variation in speed of different parts of the body during sprinting. We use an array of foreground accumulators to identify short-term static pixels and a temporal analysis of the associated static regions to identify foot contacts. We evaluated the technique using 13 videos of three sprinters. It successfully identifed 55 of the 56 contacts, with a mean localisation error of 1.39±1.05 pixels. Some videos were also seen to produce additional, spurious contacts. We present heuristics to help identify the true contacts. © 2011 Springer-Verlag Berlin Heidelberg.

High mobility N-channel and P-channel nanocrystalline silicon thin-film transistors

We report high hole and electron mobilities in nanocrystalline silicon (nc-Si:H) top-gate staggered thin-film transistors (TFTs) fabricated by direct plasma-enhanced chemical vapor deposition (PECVD) at 260°C. The n-channel nc-Si:H TFT with n+ nc-Si:H ohmic contacts shows a field-effect electron mobility (μnFE) of 130 cm2/Vs, which increases to 150 cm2/Vs with Cr-silicide contacts, along with a field-effect hole mobility (μhFE) of 25 cm2/Vs. To the best of our knowledge, the hole and electron mobilities reported here are the highest achieved to date using direct PECVD. © 2005 IEEE.

Theoretical investigation of CoSi2/Si1-xGex detectors: Influence of a Si tunneling barrier on the electro-optical characteristics

We present a theoretical investigation of the influence of a non-reacted Si layer on the transport and optical properties of CoSi2/Si1-xGex Schottky barrier diodes grown from Co/Si/Si1-xGex systems. The presence of this layer reduces the effect of the lowering of the Schottky barrier height which would be expected in a CoSi2/Si1-xGex. However, due to the small thickness of this Si layer, the charge carriers are able to tunnel through it. This tunneling process allows for a significant lowering of the Schottky barrier height and therefore an extension of the detection regime into the infrared. © 1996 American Institute of Physics.

Performance prediction of graphene nanoribbon and carbon nanotube transistors

Carbon nanotubes (CNTs) and graphene nanoribbons (GNRs) field-effect transistor (FET) can be the basis for a quasi-one- dimensional (Q1D) transistor technology. Recent experiments show that the on-off ratio for GNR devices can be improved to level exploration of transistor action is justified. Here we use the tight-binding energy dipersion approximation, to assess the performance of semiconducting CNT and GNR is qualitatively in terms of drain current drive strength, bandgap and density of states for a specified device. By reducing the maximum conductance 4e2/h by half, we observed that our model has a particularly good fit with 50 nm channel single walled carbon nanotube (SWCNT) experimental data. Given the same bandgap, CNTs outperform GNRs due to valley degeneracy. Nevertheless, the variation of the device contacts will decide which transistor will exhibit better conductivity and thus higher ON currents. © 2011 American Institute of Physics.

Molecular modeling on human CCR5 receptors and complex with CD4 antigens and HIV-1 envelope glycoprotein gp120

AIM: To investigate the interaction between human CCR5 receptors (CCR5) and HIV-1 envelope glycoprotein gp120 (HIV-1 gp120) and HIV-1 receptor CD4 antigens (CD4). METHODS: The structurally con served regions (SCR) of human CCR5 was built by the SYBYL/Biopolymer module using the corresponding transmembrane (TM) domain of bacteriorhodopsin (bR) as the template. The coordinates for amino-ter minal residue sequence, and carboxyl-terminal residue sequence, extracellular and cytoplasmic loops were generated using LOOP SEARCH algorithm. Subsequently the structural model was merged into the complex with HIV-1 gp120 and CD4. RESULTS: Human CCR5 interacted with both an HIV-1 gp120 and CD4. The N-terminal residues (especially Met1 and Gln4) of human CCR5, contacted with CD4 residues, mainly 7Nith one span (56 - 59) of CD4 in electrostatic interaction and hydrogen-bonds. The binding sites of human CCR5 were buried in a hydrophobic center surrounded by a highly basic periphery. On the other hand, direct interatomic contacts were made between ? CCR5 residues and 6 gp120 amino-acid residues, which included van der Waals contacts, hydrophobic interaction, and hydrogen bonds. CONCLUSION: The interaction model should be helpful for rational design of novel anti-HIV drugs.

Structural and functional characterization of the human CCR5 receptor in complex with HIV gp120 envelope glycoprotein and CD4 receptor by molecular modeling studies

The entry of human immunodeficiency virus (HIV) into cells depends on a sequential interaction of the gp120 envelope glycoprotein with the cellular receptors CD4 and members of the chemokine receptor family. The CC chemokine receptor CCR5 is such a receptor for several chemokines and a major coreceptor for the entry of R5 HIV type-1 (HIV-1) into cells. Although many studies focus on the interaction of CCR5 with HIV-1, the corresponding interaction sites in CCR5 and gp120 have not been matched. Here we used an approach combining protein structure modeling, docking and molecular dynamics simulation to build a series of structural models of the CCR5 in complexes with gp120 and CD4. Interactions such as hydrogen bonds, salt bridges and van der Waals contacts between CCR5 and gp120 were investigated. Three snapshots of CCR5-gp120-CD4 models revealed that the initial interactions of CCR5 with gp120 are involved in the negatively charged N-terminus (Nt) region of CCR5 and positively charged bridging sheet region of gp120. Further interactions occurred between extracellular loop2 (ECL2) of CCR5 and the base of V3 loop regions of gp120. These interactions may induce the conformational changes in gp120 and lead to the final entry of HIV into the cell. These results not only strongly support the two-step gp120-CCR5 binding mechanism, but also rationalize extensive biological data about the role of CCR5 in HIV-1 gp120 binding and entry, and may guide efforts to design novel inhibitors.

Complementary metal-oxide-semiconductor-compatible and self-aligned catalyst formation for carbon nanotube synthesis and interconnect fabrication

We have for the first time developed a self-aligned metal catalyst formation process using fully CMOS (complementary metal-oxide-semiconductor) compatible materials and techniques, for the synthesis of aligned carbon nanotubes (CNTs). By employing an electrically conductive cobalt disilicide (CoSi 2) layer as the starting material, a reactive ion etch (RIE) treatment and a hydrogen reduction step are used to transform the CoSi 2 surface into cobalt (Co) nanoparticles that are active to catalyze aligned CNT growth. Ohmic contacts between the conductive substrate and the CNTs are obtained. The process developed in this study can be applied to form metal nanoparticles in regions that cannot be patterned using conventional catalyst deposition methods, for example at the bottom of deep holes or on vertical surfaces. This catalyst formation method is crucially important for the fabrication of vertical and horizontal interconnect devices based on CNTs. © 2012 American Institute of Physics.