Estudo e conceção de um sistema de encaixe rápido e simples para próteses de membros inferiores

Dissertação de mestrado integrado em Engenharia Biomédica

Comparação da funcionalidade de diferentes tipos de pés protésicos

Introdução - Amputação é uma cirurgia destrutiva / construtiva, nestas situações a restauração da capacidade da marcha só pode ocorrer mediante: uma adaptação na marcha, uma utilização ótima da musculatura remanescente e a utilização de uma prótese. Na bibliografia está descrito que 85% de todas as amputações são do membro inferior, sendo a amputação transtibial a amputação mais frequente; com uma predominância em indivíduos do sexo masculino (75% dos casos), com idades compreendidas entre os 50 e 75 anos e existindo um predomínio das amputações de etiologia vascular. De acordo com alguns autores, estes dados são também uma realidade em Portugal. Os indivíduos que sofrem uma amputação da extremidade inferior apresentam uma deterioração funcional variada, neste tipo de amputações, quer sejam amputados unilaterais ou bilaterais, transfemorais ou transtibiais, existem alterações na marcha que resultam numa diminuição da mobilidade. Existem diferentes fatores que podem influenciar o padrão de marcha de um amputado: derivados da protetização; que afetam a interface membro residual / prótese; relativos ao segmento intermédio da prótese; que dependem do mecanismo articular e os relacionados com a porção distal das próteses. Apesar destes fatores, os estudos em que se analisa o efeito do tipo de mecanismo protésico sobre a marcha do amputado transtibial são reduzidos. Não existindo bases científicas claras para a seleção dos mecanismos que melhor se adaptam a cada caso, usualmente o médico que prescreve a prótese escolhe uma ou outra, de acordo com as suas preferências pessoais, com a moda ou com a sua experiência profissional. Neste sentido torna-se importante desenvolver metodologias que possibilitem ao profissional prescritor avaliar, com dados quantificáveis qual a melhor escolha (personalizada ao paciente), quais os componentes mais indicados no fabrico de uma prótese. Objetivo do estudo - O objetivo deste estudo foi determinar qual dos pés protésicos melhor se adequa à funcionalidade do sujeito. Apresentando uma metodologia de avaliação de componentes protésicos (pés) que possa ser reproduzida periodicamente.

Comparação da contenção farmacológica com cetamina e xilazina, administradas pela via intramuscular no membro torácico ou pélvico, em jacarés-do-papo-amarelo juvenis

Os répteis possuem um sistema porta-renal, o qual pode desviar parte do sangue proveniente das porções caudais do corpo aos rins antes que a mesma atinja a circulação sistêmica. Em vista disto, vem sendo aconselhada a administração de medicamentos injetáveis nos membros torácicos, para que se evite a filtração imediata pelo parênquima renal, causando redução do efeito esperado. O objetivo do presente estudo foi comparar aspectos qualitativos e quantitativos da associação de cetamina (30 mg/kg) e xilazina (1 mg/kg), injetada no membro torácico ou pélvico, em jacarés-do-papo-amarelo (Caiman latirostris) juvenis. Oito animais machos com peso médio (±DP) de 1,3 (±0,3) kg e, aproximadamente, dois anos de idade foram anestesiados em duas ocasiões distintas com intervalo de sete dias. Em cada ocasião, os animais receberam, de forma aleatória, a associação anestésica por via intramuscular em membro torácico (tratamento MT) ou pélvico (tratamento MP). Foram avaliados os intervalos de tempo entre a administração do tratamento e a perda do reflexo de endireitamento (período de indução), entre a perda e o retorno desse reflexo (duração do efeito clínico importante) e entre o retorno do reflexo de endireitamento e os primeiros movimentos de deambulação (duração do efeito residual), as frequências cardíaca e respiratória e as temperaturas ambiental e cloacal. Os escores de sedação/anestesia foram avaliados através de uma escala com variação de 0 (alerta/consciente) a 10 (anestesia profunda/sobredosagem). No tratamento MP, dois animais não apresentaram perda de reflexo de endireitamento. Considerando somente aqueles que apresentaram a perda desse reflexo, o tempo de indução (21±9 e 17±5 minutos) e a duração do efeito clínico importante (35±19 e 43±21 minutos) e residual (28±31 e 12±11 minutos) foram similares entre os tratamentos MT e MP (média±desvio padrão). O escore de sedação foi significativamente maior que o basal de 20 a 50 minutos nos dois tratamentos e, aos 30 minutos (pico de efeito), o escore mediano (interquartil) foi 3,5(2,3-4,0) no tratamento MT e 3,0(2,0-4,0) no tratamento MP. Assim como nos escores de sedação, diferenças entre tratamentos nas variáveis fisiológicas não foram observadas. Em ambos os tratamentos, o reflexo de retirada de membro ao pinçamento digital não foi abolido. A administração da associação de xilazina e cetamina em membro pélvico ou torácico de jacarés-do-papo-amarelo juvenis promove efeitos similares, sugerindo que a influência do sistema porta-renal não é clinicamente relevante. Nas doses empregadas, tal protocolo não promove anestesia cirúrgica e a imobilidade/contenção farmacológica é imprevisível e de curta duração.

Sucessão estratigráfica e tratos de sistemas do Membro Romualdo, porção leste da Bacia do Araripe, nordeste do Brasil

Located in northeastern Brazil, the evolution of Araripe Basin has been associated with the fragmentation of Gondwana and opening of the South Atlantic. The Santana Formation belongs to the post-rift sequence of the basin and is characterized by the presence of laminated limestones in the lower portion (Mb. Crato), evaporite (Ipubi) and siliciclastics (Mb. Romualdo). For better understanding of the Romualdo's stratigraphy, depositional environments and tract of systems, a stratigraphic analysis was made with representative columnar sections of the unit. Sedimentary facies have been described in detail, as well as paleocurrents measured at different stratigraphic levels. It was found that the contact of Mb. Romualdo with the carbonate-evaporite section (Mbs. Crato and Ipubi) is a unconformity, evidenced by residual lags and thin layers of conglomerates above the contact. Above the conglomeratic levels predominate fine sandstones / medium interlayered with calciferous green shales. The percentage of shales increases towards the top, featuring retrogradational stacking culminating in layers of coquinas, excellent stratigraphic mark in the basin. Thin layers of coquins of gastropods comprising equinoids, located on the shale section, present in three sections marine deposits are associated with surfaces ravine. The upper section is characterized by recurrent facies of green shales, sandstones intercalated with sandstones progressively become more frequent towards the top of the unit, featuring the regressive part of the cycle. The sandstones present cross-stratification, often with mud clasts and clay layers in the foresets, and beddings of flaser type and wavy in heterolitic facies, suggesting the action of tidal currents. Paleocurrents measured in the sandstones show gaps with opposite flow directions outlining bipolar standards, which reinforce the interpretation of shallow marine environment influenced by tides during the sedimentation...

Photocatalytic Degradation Of Ofloxacin And Evaluation Of The Residual Antimicrobial Activity.

Ofloxacin is an antimicrobial agent frequently found in significant concentrations in wastewater and surface water. Its continuous introduction into the environment is a potential risk to non-target organisms or to human health. In this study, ofloxacin degradation by UV/TiO2 and UV/TiO2/H2O2, antimicrobial activity (E. coli) of samples subjected to these processes, and by-products formed were evaluated. For UV/TiO2, the degradation efficiency was 89.3% in 60 min of reaction when 128 mg L(-1) TiO2 were used. The addition of 1.68 mmol L(-1) hydrogen peroxide increased degradation to 97.8%. For UV/TiO2, increasing the catalyst concentration from 4 to 128 mg L(-1) led to an increase in degradation efficiency. For both processes, the antimicrobial activity was considerably reduced throughout the reaction time. The structures of two by-products are presented: m/z 291 (9-fluoro-3-methyl-10-(methyleneamino)-7-oxo-2,3-dihydro-7H-[1,4]oxazino[2,3,4-ij]quinoline-6-carboxylic acid) and m/z 157 ((Z)-2-formyl-3-((2-oxoethyl)imino)propanoic acid).

Caracterização física e mecânica de argamassas à base de cimento Portland e cinza de casca de arroz residual

Rice husk, employed as an energy source at milling industries in Brazil generates, after burning, a dark ash. This residue is not yet conveniently disposed, being currently dumped on large areas, causing environmental problems. This research intended to evaluate the applications of residual rice husk ashes (RHA) as a partial replacement of cement for mortar production. Rice husk ash was chemically characterized through X-ray fluorescence, determination of carbon content, X-ray diffraction, and laser granulometric analysis. Mortar specimens were submitted to two different exposure conditions: internal and external environments at a maximum period of five months. Physical-mechanical testing were compressive strength and ultrasonic pulse velocity (UPV). Although presenting good mechanical performance, the mortar based on ash (RHA) did not present pozolanicity but it can be employed in cement matrices as inert material (filler).

Efeito residual no triathlon : como nadar influência nas etapas seguintes

Universidade Estadual de Campinas. Faculdade de Educação Física

The influence of residual salivary fluoride from dentifrice on enamel erosion: an in situ study

The objective of this study was to assess the salivary residual effect of fluoride dentifrice on human enamel subjected to an erosive challenge. This crossover in situ study was performed in two phases (A and B), involving ten volunteers. In each phase, they wore acrylic palatal appliances, each containing 3 human enamel blocks, during 7 days. The blocks were subjected to erosion by immersion of the appliances in a cola drink for 5 minutes, 4 times a day. Dentifrice was used to brush the volunteers’ teeth, 4 times a day, during 1 minute, before the appliance was replaced into the mouth. In phases A and B the dentifrices used had the same formulation, except for the absence (PD) or presence (FD) of fluoride, respectively. Enamel alterations were determined using profilometry, microhardness (%SMHC), acid- and alkali-soluble F analysis. The data were tested using ANOVA (p < 0.05). The concentrations (mean ± SD) of alkali- and acid-soluble F (µgF/cm²) were, respectively, PD: 1.27ª ± 0.70/2.24A ± 0.36 and FD: 1.49ª ± 0.44/2.24A ± 0.67 (p > 0.05). The mean wear values (± SD, µm) were PD: 3.63ª ± 1.54 and FD: 3.54ª ± 0.90 (p > 0.05). The mean %SMHC values (± SD) were PD: 89.63ª ± 4.73 and FD: 87.28ª ± 4.01 (p > 0.05). Thus, we concluded that the residual fluoride from the fluoride-containing dentifrice did not protect enamel against erosion.

Efeito residual da silicatagem no solo e na produtividade do capim-marandu sob pastejo

A escória siderúrgica é uma alternativa para a correção da acidez dos solos e é constituída de silicato de cálcio. Neste estudo, avaliaram-se os efeitos residuais da aplicação de silicato de cálcio nos atributos químicos do solo e da planta em Latossolo Vermelho distroférrico típico com capim-Marandu (Brachiaria brizantha cv. Marandu), sob intensidades de pastejo em lotação rotacionada. O delineamento experimental foi de blocos ao acaso, com intensidades de pastejo avaliadas pelas ofertas diárias de forragem de 50, 100, 150 e 200 kg t-1 de MS por PV nas parcelas experimentais, enquanto a aplicação superficial de silicato de cálcio combinado com calcário dolomítico, respectivamente, nas doses 0 + 0; 2 + 0; 4 + 0; 6 + 0; 2 + 4; 4 + 2 e 0 + 6 t ha- 1 nas subparcelas com quatro repetições, duas épocas (verão e inverno) e avaliação em três profundidades do solo (0-10, 10-20 e 20-40 cm). Os atributos químicos do solo pH em CaCl2, Ca, Mg, K, H + Al e V, avaliados 720 dias após a aplicação, apresentaram resultados favoráveis do poder residual do silicato de Ca e do calcário. A oferta de forragem 200 kg t-1 e o tratamento somente com calcário dolomítico (0 + 6 t ha-1) elevaram o valor de pH em CaCl2 e o V, principalmente na camada de 0-10 cm. Os teores de Si no solo foram influenciados pelas doses aplicadas de silicato de Ca, apesar de não terem causado alterações significativas nos teores foliares de Si. A composição químico-bromatológica foi afetada somente pelas ofertas e épocas. As ofertas, épocas e a interação época x oferta resultaram em efeitos na produção de matéria seca no pré-pastejo, com maiores produções para a oferta 200 kg t-1 e menores para a de 50 kg t-1 nas duas épocas. O resíduo (pós-pastejo) foi influenciado pelas ofertas e épocas. As ofertas 50 e 100 kg t-1 e o tratamento com 2 t ha-1 de silicato de Ca promoveram as maiores taxas de acúmulo de matéria seca.

Simplified flow cytometric assay to detect minimal residual disease in childhood with acute lymphoblastic leukemia

The detection of minimal residual disease (MRD) is an important prognostic factor in childhood acute lymphoblastic leukemia (ALL) providing crucial information on the response to treatment and risk of relapse. However, the high cost of these techniques restricts their use in countries with limited resources. Thus, we prospectively studied the use of flow cytometry (FC) with a simplified 3-color assay and a limited antibody panel to detect MRD in the bone marrow (BM) and peripheral blood (PB) of children with ALL. BM and PB samples from 40 children with ALL were analyzed on days (d) 14 and 28 during induction and in weeks 24-30 of maintenance therapy. Detectable MRD was defined as > 0.01% cells expressing the aberrant immunophenotype as characterized at diagnosis among total events in the sample. A total of 87% of the patients had an aberrant immunophenotype at diagnosis. On d14, 56% of the BM and 43% of the PB samples had detectable MRD. On d28, this decreased to 45% and 31%, respectively. The percentage of cells with the aberrant phenotype was similar in both BM and PB in T-ALL but about 10 times higher in the BM of patients with B-cell-precursor ALL. Moreover, MRD was detected in the BM of patients in complete morphological remission (44% on d14 and 39% on d28). MRD was not significantly associated to gender, age, initial white blood cell count or cell lineage. This FC assay is feasible, affordable and readily applicable to detect MRD in centers with limited resources.

Phase transformation and residual stress probed by Raman spectroscopy in diamond-turned single crystal silicon

Single-point diamond turning of monocrystalline semiconductors is an important field of research within brittle materials machining. Monocrystalline silicon samples with a (100) orientation have been diamond turned under different cutting conditions (feed rate and depth of cut). Micro-Raman spectroscopy and atomic force microscopy have been used to assess structural alterations and surface finish of the samples diamond turned under ductile and brittle modes. It was found that silicon undergoes a phase transformation when machined in the ductile mode. This phase transformation is evidenced by the creation of an amorphous surface layer after machining which has been probed by Raman scattering. Compressive residual stresses are estimated for the machined surface and it is observed that they decrease with an increase in the feed rate and depth of cut. This behaviour has been attributed to the formation of subsurface cracks when the feed rate is higher than or equal to 2.5 mu m/rev. The surface roughness was observed to vary with the feed rate and the depth of cut. An increase in the surface roughness was influenced by microcrack formation when the feed rate reached 5.0 mu m/rev. Furthermore, a high-pressure phase transformation induced by the tool/material interaction and responsible for the ductile response of this typical brittle material is discussed based upon the presented Raman spectra. The application of this machining technology finds use for a wide range of high quality components, for example the creation of a micrometre-range channel for microfluidic devices as well as microlenses used in the infrared spectrum range.

A simplified minimal residual disease polymerase chain reaction method at early treatment points can stratify children with acute lymphoblastic leukemia into good and poor outcome groups

Background Minimal residual disease is an important independent prognostic factor in childhood acute lymphoblastic leukemia. The classical detection methods such as multiparameter flow cytometry and real-time quantitative polymerase chain reaction analysis are expensive, time-consuming and complex, and require considerable technical expertise. Design and Methods We analyzed 229 consecutive children with acute lymphoblastic leukemia treated according to the GBTLI-99 protocol at three different Brazilian centers. Minimal residual disease was analyzed in bone marrow samples at diagnosis and on days 14 and 28 by conventional homo/heteroduplex polymerase chain reaction using a simplified approach with consensus primers for IG and TCR gene rearrangements. Results At least one marker was detected by polymerase chain reaction in 96.4%, of the patients. By combining the minimal residual disease results obtained on days 14 and 28, three different prognostic groups were identified: minimal residual disease negative on days 14 and 28, positive on day 14/negative on day 28, and positive on both. Five-year event-free survival rates were 85%, 75.6%,, and 27.8%, respectively (p<0.0001). The same pattern of stratification held true for the group of intensively treated children. When analyzed in other subgroups of patients such as those at standard and high risk at diagnosis, those with positive B-derived CD10, patients positive for the TEL/AML1 transcript, and patients in morphological remission on a day 28 marrow, the event-free survival rate was found to be significantly lower in patients with positive minimal residual disease on day 28. Multivariate analysis demonstrated that the detection of minimal residual disease on day 28 is the most significant prognostic factor. Conclusions This simplified strategy for detection of minimal residual disease was feasible, reproducible, cheaper and simpler when compared with other methods, and allowed powerful discrimination between children with acute lymphoblastic leukemia with a good and poor outcome.

Influence of the microstructure in the collapse of a residual clayey tropical soil

A typical residual clayey soil originating from basalt in southern Brazil has been analyzed in order to assess the influence of wetting-induced deformation and microstructural features on the collapse behavior. Single and double oedometer tests were undertaken on a soil profile to 9 m depth. The results indicated collapsible behaviour at all profile depths. The influence of pre-consolidation stress and pedogenetic factors in the variability of the physical characteristics of the soil and in the magnitude of the collapse was noted. The collapse coefficient has been shown to be related to the both the microaggregate plasma and the varying nature of the pores and their interconnectivity.

Specific methanogenic activity in an anaerobic-aerobic reactor applied to the treatment of domestic residual water

The specific methanogenic activity (SMA) test is an important tool for the monitoring of anaerobic digestion. This paper presents the behavior of the methanogenic archaea of an anaerobic sludge under different conditions of oxygenation in a fixed-bed anaerobic-aerobic reactor treating domestic sewage. The reactor was operated in a continuous manner under different liquid recycle ratios from aerobic to anaerobic zones in order to remove carbon and nitrogen. The application of the SMA test was adapted from several authors and the measurement of the accumulated methane in the reactor was carried out by means of gas chromatography. Methanogenic organisms were not inhibited by the presence of oxygen. In contrast, the values of CH, production rate by sludge exposed to oxygen were greater than those obtained for strictly anaerobic sludge.

Internal Residual Stresses in Sintered and Commercial Low Expansion Li(2)O-Al(2)O(3)-SiO(2) Glass-Ceramics

We performed Synchrotron X-ray diffraction (XRD) analyses of internal residual stresses in monolithic samples of a newly developed Li(2)O-Al(2)O(3)-SiO(2) (LAS) glass-ceramic produced by sintering and in a commercial LAS glass-ceramic, CERAN (R), produced by the traditional crystal nucleation and growth treatments. The elastic constants were measured by instrumented indentation and a pulse-echo technique. The thermal expansion coefficient of virgilite was determined by high temperature XRD and dilatometry. The c-axis contracts with the increasing temperature whereas the a-axis does not vary significantly. Microcracking of the microstructure affects the thermal expansion coefficients measured by dilatometry and thermal expansion hysteresis is observed for the sintered glass-ceramic as well as for CERAN (R). The measured internal stress is quite low for both glass-ceramics and can be explained by theoretical modeling if the high volume fraction of the crystalline phase (virgilite) is considered. Using a modified Green model, the calculated critical (glass) island diameter for spontaneous cracking agreed with experimental observations. The experimental data collected also allowed the calculation of the critical crystal grain diameters for grain-boundary microcracking due to the anisotropy of thermal expansion of virgilite and for microcracking in the residual glass phase surrounding the virgilite particles. All these parameters are important for the successful microstructural design of sintered glass-ceramics.