RCAAP Repository

INTRODUÇÃO: O e-learning surgiu como uma forma complementar de ensino, trazendo consigo vantagens como o aumento da acessibilidade da informação, aprendizado personalizado, democratização do ensino e facilidade de atualização, distribuição e padronização do conteúdo. Neste sentido, o presente trabalho tem como objeto apresentar uma ferramenta, intitulada de ISE-SPL, cujo propósito é a geração automática de sistemas de e-learning para a educação médica, utilizando para isso sistemas ISE (Interactive Spaced-Education) e conceitos de Linhas de Produto de Software. MÉTODOS: A ferramenta consiste em uma metodologia inovadora para a educação médica que visa auxiliar o docente da área de saúde na sua prática pedagógica por meio do uso de tecnologias educacionais, todas baseadas na computação aplicada à saúde (Informática em Saúde). RESULTADOS: Os testes realizados para validar a ISE-SPL foram divididos em duas etapas: a primeira foi feita através da utilização de um software de análise de ferramentas semelhantes ao ISE-SPL, chamado S.P.L.O.T; e a segunda foi realizada através da aplicação de questionários de usabilidade aos docentes da área da saúde que utilizaram o ISE-SPL. CONCLUSÃO: Ambos os testes demonstraram resultados positivos, permitindo comprovar a eficiência e a utilidade da ferramenta de geração de softwares de e-learning para o docente da área da saúde.

INTRODUCTION: Ultrasound Transit-Time flowmeters are based on the fact that the time required for an ultrasound pulse to propagate through a given distance in a moving medium is a function of the vectorial sum of pulse propagation velocity and medium velocity. The most common application of this flowmeter in medicine is in the evaluation of blood flow in arteries and veins during heart vascular surgery. The present article describes the design, construction and evaluation of a flow phantom for transit-time flowmeters calibration. METHODS: Basically, it is a hydraulic circuit containing degassed and distilled water. In such a circuit, a constant differential water level is established between two columns that are interconnected by tubes with defined resistance, which determines a known flow rate. A basic theoretical model to estimate the system Reynolds Number and resistance was developed. RESULTS: A flow range between 4.43 ± 0.18 ml.min-1 and 106.88 ± 0.27 ml.min-1 was found to be compatible with physiological values in small vessels. The pressure range was between 0.20 ± 0.03 cmH2O and 12.53 ± 0.07 cmH2O, and the larger Reynolds Number was 1134.07. Experimental and theoretical resistance values were similar. CONCLUSION: A reproducible phantom was designed and built to be assembled with standard low-cost materials and is capable of generating adjustable and continuous flows that can be used to calibrate TTFM systems.

INTRODUCTION: Skin health and skin care to reduce the effects of aging are the main interests of many researchers. The skin is very important because it protects the body from various effects of the external environment, and studies of the largest organ of the human body have been conducted since antiquity. In skin, aging effects are severe enough to promote changes in cell structure and biochemical composition. In this study, we quantitatively analyzed the water content and natural moisturizing factor of human facial skin in vivo and in real time by confocal Raman spectroscopy. This non-invasive technique is capable of providing detailed information on the biochemical composition at different depth profiles in the skin. METHODS: We studied 10 volunteers, phototype II (40 and 50 years old), using a confocal Raman system to examine the skin surface down to 25 µm. Raman spectra were obtained before product use (T0), and after 30 days of continuous use of cosmetics (T30). RESULTS: The results show a significant increase of 6.4% in water content in the surface layer of the facial skin after the cosmetic use. The amounts of natural moisturizing factor (NMF) compounds were also increased. Urocanic acid underwent a greater change in relation to carboxylic acid pyrrolidone, with a 38.5% increase in the stratum corneum. CONCLUSION: Confocal Raman spectroscopy identified changes in the biochemical composition of the superficial layers of the epidermis, which suggests the anti-aging efficacy of the formulation.

INTRODUCTION: Function induction problems are frequently represented by affinity measures between the elements of the inductive sample set, and kernel matrices are a well-known example of affinity measures. METHODS: The objective of the present work is to obtain information about the relations between data from a calculated kernel matrix by initially assuming that those geometric relations are consistent with known labels. To assess the relation between the data structure and the labels, a classifier based on kernel density estimation (KDE) was used. The performance of the selected width using the method presented in this paper was compared to the performance of a method described in the literature; the literature method was based on minimizing error minimization and balancing bias and variance. The main case study, which was to predict the response to neoadjuvant chemotherapy treatment, consists of evaluating whether a set of training data from genomic expression data from breast tumors and the genomic expression from the tumor of one patient can be used to determine whether there will be a pathological complete response. RESULTS: For the tested databases, the proposed method showed statistically equivalent results with the literature method; however, in some cases, the proposed method had a better overall performance when considering both large and small classes. CONCLUSION: The results demonstrate the feasibility of selecting models by directly calculating densities and the geometry from the class separation.

INTRODUCTION: Increased production and disorders in the circulation or absorption of cerebrospinal fluid (CSF) leads to increased intracranial pressure and causes a condition called hydrocephalus. The most common treatment for this disorder is the implantation of a ventricle-peritoneal shunt, which consists of the insertion of a ventricular catheter in the cerebral ventricle, a neurological valve for drainage control and a peritoneal catheter that leads the CSF to the abdominal region. The International Organization for Standardization (ISO) 7197 introduced requirements for the design and production of the shunts and neurological valve, including in vitro hydrodynamic tests, which are indispensable for evaluating the performance of the CSF drainage systems. METHODS: A testing rig built in accordance with ISO 7197 was evaluated for the uncertainty of flow and opening and closing pressure measurements, the pressure-flow relationship and reflux neurological valve resistance. The infusion pump and pressure measurement system were evaluated for calibration, hysteresis behavior and stability to determine the experimental uncertainties from hydrodynamic testing of two commercial products. RESULTS: The equipment showed uncertainties of less than 1% in the infusion pump, less than 4% in the pressure sensor and adequate performance for the hydrodynamic tests. CONCLUSION: The hydrodynamic test rig allowed the opening and closing pressures and the resistance to reflux to be obtained, and it also allowed the determination of the pressure and flow rate characteristics of two neurological commercial valves with experimental uncertainties that do not impact the results and the evaluation of in vitro performance of a shunt.

INTRODUCTION: Breast cancer is the second most common type of cancer in the world, being more common among women and representing 22% of all new cancer cases every year. The sooner it is diagnosed, the better the chances of a successful treatment are. Mammography is one way to detect non-palpable tumors that cause breast cancer. However, it is known that the sensitivity of this exam can vary considerably due to factors such as the specialist's experience, the patient's age and the quality of the images obtained in the exam. The use of computational techniques involving artificial intelligence and image processing has contributed more and more to support the specialists in obtaining a more precise diagnosis. METHODS: This paper proposes a methodology that exclusively uses texture analysis to describe features of masses in digitized mammograms. To increase the efficiency of texture feature extraction, the diversity index's capability to detect patterns of species co-occurrence is used. For this purpose, the Gleason and Menhinick indexes are used. Finally, the extracted texture is classified using the Support Vector Machine, looking to differentiate the malignant masses from the benign. RESULTS: The best result was obtained using the Gleason index, with 86.66% accuracy, 90% sensitivity, 83.33% specificity and an area under the ROC Curve (Az) of 0.86. CONCLUSION: Both indexes showed statistically similar performance; however, the Gleason index was slightly superior.

INTRODUCTION: Patients with diabetes mellitus exhibit a delay in the lesion repair process. The active components of Cenostigma macrophyllum may represent a viable alternative to facilitate the recovery of these lesions. The aim of this study was to evaluate the effects of emulsion oil-water Cenostigma macrophyllum in the repair process of lesions in rats with induced diabetes. METHODS: 63 male rats (Wistar, 200-250 g body weight, 30-40 days old) were distributed into the following groups: control (C), diabetic (D) and diabetic treated with Cenostigma macrophyllum (P), subdivided based on the experimental times, days 7, 14 and 28, with 21 animals per main group. Diabetes mellitus (DM) was induced by administration of streptozotocin (50 mg/kg via penile vein and 12-h fasting) and confirmed at day 21 (glycemic index &gt; 240 mg/dL). In the animals of group P, 0.5 ml of the oil-water emulsion obtained from the plant seed was used. The samples were removed and hemisectioned, and one portion was used for the quantitative histological analysis of collagen using Masson's trichrome staining, while another portion was analyzed by FT-Raman spectroscopy. RESULTS: A higher percentage area of the volume of collagen fibers was observed for the experimental time Day 14 in group P compared with group D (p < 0.001). Regarding the ratio of areas of the amides I (1700‑1600 cm-1) and III (1245-1345 cm-1), the groups D and P show the opposite behavior. CONCLUSION: Cenostigma macrophyllum accelerated the repair process in skin of diabetic ratsfor14 days.

INTRODUCTION: Rheumatic diseases are considered public health problems affecting millions of people worldwide resulting in high and rising health-care costs. In this work, Fourier Transform Infrared spectroscopy associated to Partial Least Square regression (PLS) analysis was used to diagnose rheumatoid arthritis (RA) from human serum. METHODS: The sera of 94 individuals were collected, which included 47 from rheumatic patients and 47 from healthy individuals. The results from PLS analysis were compared to standard clinical trials such as anti-citrullinated peptide antibodies, C- Reactive protein, and Rheumatoid factor. RESULTS: For clinical diagnosis, the anti-citrullinated peptide antibodies of second generation proved to be the most specific to diagnosis rheumatoid arthritis even after long periods of drug therapy. CONCLUSIONS: The qualitative PLS analysis has shown higher values of IgM of RA group, but the difference was very small. The RA patients were under medication, which interfered with the IgM concentration.

INTRODUCTION: Decision-making on medical equipment management is a daily task for clinical engineers, but it may prove difficult to easily extract relevant information from the large amount of data from computerized maintenance management systems. This article describes a simple method of medical equipment classification based on corrective maintenance indicators. METHODS: Three indicators were calculated based on the number of events, duration and cost of corrective maintenance. Three classes were defined according to the indicator values of different equipment ages: class A for 0-4 years, class B for 5-9 years, and class C for equipment older than 10 years. The method was applied to 2,134 pieces of equipment from the Health Service system of the University of Campinas. RESULTS: From the total, 51.7% of the equipment were classified as C, 4.2% as B and 44.1% as A. The infusion pump for general use was the type of equipment of which most units were in the C class (84.7%), even though almost 50% of them were acquired within less than 9 years, and would thus be expected to be classified as A and B. Among the pumps in class C, 39.5% were from a single manufacturer, although the equipments were acquired recently. CONCLUSION: The developed classification may be an important tool for raising alerts about equipment more prone to maintenance problems, as well as for identification of equipments with acceptable maintenance history, supporting decision-making on equipment replacement.

INTRODUCTION: Areas of the brain that are associated with the vestibular system can be activated using galvanic vestibular stimulation. These areas can be studied through a combination of galvanic vestibular stimulation with functional magnetic resonance imaging (fMRI). In order to provide an appropriate sequence of galvanic stimulation synchronous with the MRI pulse sequence, a specific electronic device that was built and assessed is presented. METHODS: The electronic project of the GVS is divided in analog and digital circuits. The analog circuits are mounted in an aluminum case, supplied by sealed batteries, and goes inside the MRI room near to the feet of the subject. The digital circuits are placed in the MRI control room. Those circuits communicate through each other by an optical fiber. Tests to verify the GVS-MRI compatibility were conducted. Silicone (in-house) and Ag/AgCl (commercial) electrodes were evaluated for maximum balance and minimal pain sensations. fMRI experiments were conducted in eight human volunteers. RESULTS: GVS-MRI compatibility experiments demonstrate that the GVS did not interfere with the MRI scanner functionality and vice versa. The circular silicone electrode was considered the most suitable to apply the galvanic vestibular stimulation. The 1 Hz stimulation sinusoid frequency produced the biggest balance and the less pain sensations when compared to 2 Hz. The GVS was capable of eliciting activation in the precentral and postcentral gyri, in the central sulcus, in the supplementary motor area, in the middle and inferior frontal gyri, in the inferior parietal lobule, in the insula, in the superior temporal gyrus, in the middle cingulate cortex, and in the cerebellum. CONCLUSION: This study shows the development and description of a neurovestibular stimulator that can be safely used inside the MRI scanner room without interfering on its operation and vice versa. The developed GVS could successfully activate the major areas involved with multimodal functions of the vestibular system, demonstrating its validity as a stimulator for neurovestibular research. To the best of our knowledge, this is the first work that shows the development and the construction of a galvanic vestibular stimulator that could be safely used inside the MRI room.

INTRODUCTION: Regenerative therapies using biomaterials require accurate information on interactions between the implanted material and the human body. To improve the process of bone regeneration it is necessary to obtain a better understanding of the influence of the surfaces on the early stages of osseointegration. This work aims to investigate the dynamic interaction between simulated body fluid (SBF) and titanium surfaces (Ti cp) immediately after their first contact. METHODS: Ti cp samples were passed through physicochemical treatments after immersion in acid solution, alkaline solution and solutions containing TiO2 and Ca2+, to obtain three different surfaces. These were characterized by electron microscopy and free energy estimates. The evaluation of the interaction with SBF was performed by measuring the dynamic contact angles after contacting the surfaces. RESULTS: The effects of SBF wettability were more significant on surfaces according to high energy estimates. A comparative analysis of the three types of surfaces showed that fluid spreading was greater in samples with greater polar components, indicating that the surface nature influences interactions in the early stages of osseointegration. CONCLUSION: The results indicate the influence of polar interactions in the dynamic wettability of the SBF. It is possible that these interactions can also influence cellular viability on surfaces. Based on these results, new experiments are being designed to improve the presented methodology as a tool for the evaluation of biomaterials without the need for in vivo experiments.

INTRODUCTION: Trabecular bones have a porous microstructure and can be modeled as linear elastic solids, heterogeneous and anisotropic. In the literature, few investigations have compared the two- dimensional (2D) and three-dimensional (3D) morphometric analyses of cancellous bone. METHODS: In this investigation eighteen cylindrical samples of cancellous bone (10 mm of diameter and 20 mm of height) were obtained from six bovine head femurs, with similar values for the weight and age, of the same race and gender. The samples were harvested and freezed at - 20 °C before carrying out the microCT analysis. The CT-Analyzer software was used to measure in three directions (superior-inferior, lateral-medial and anterior-posterior) parameters such as trabecular thickness, trabecular separation, trabecular number and the eigenvalues of the fabric tensor (M). RESULTS: The Comparison of 2D and 3D analyses for the parameters: 2D (plate model) trabecular thickness, trabecular separation and trabecular number were statistically different (p = 0) showing that measurements are not similar to the 3D ones. However, 2D (rod model) trabecular thickness and 3D trabecular thickness measurements presented no significant difference (p = 0.26). The eigenvalues show that the bovine trabecular microstructure has a tendency to transverserly isotropic symmetry. DISCUSSION: The method proved to be quite interesting for the characterization of the bone structure through 3D measurements of trabecular bone morphometric parameters in the three possible directions of loading. The results show that x-ray microtomography (∝CT) is a technique of great potential for characterization and generating bone quality parameters for the diagnosis of bone metabolism diseases.

INTRODUCTION: Continuous Positive Airway Pressure (CPAP) is a mode of non-invasive mechanical ventilation commonly used in neonatology. The incorporation of new therapeutic and technological advances may impact the survival of very low birth weight preterm infants. However, one of the difficulties faced is the high cost of this device and its numerous add-on functions, such as Apnea Hypopnea Index (AHI), flow limitation, among others. Thus, in this study, we aim to address the design and construction of a CPAP device prototype to be used in a Neonatal Intensive Care Unit (NICU). METHODS: In order to design the experimental CPAP device with sensory instrumentation for providing data to a micro-controlled system, electro-pneumatic circuits and signal conditioning boards of sensors have been fitted to achieve optimized CPAP function with low energy consumption. While running this setup, a metrological study was carried out to evaluate the sensors' performance. The methodology employed for the study was the IDOV (Identify, Design, Optimize, and Validate) method, a variant of six sigma, to minimize the failure rates. It is expected that it works under valve activation to maintain positive pressure in the airways of the patient (neonate). RESULTS: The whole system performs satisfactorily (low noise level) for each assessed module. Additionally, it is emphasized that software development for application control has resulted in a significant improvement of hardware functions. CONCLUSION: In this work, a system that performs the CPAP function was obtained; the research has shown that, by adopting a specific purpose, it may create a better understanding of Assistive Technology.

INTRODUCTION: The present study proposes a new scientific project for the seat of a wheelchair, suggesting that, through the properties of a three plan mobile seat, the pelvis of individuals with neuromotor dysfunctions may position themselves adequately, allowing a chain effect, with innumerable benefits to the users, such as prevention of deformities, of muscle shortening, of pressure ulcers and improved functionality. In spite of innumerable wheelchair models available in market, none presents the ample properties resembling the articulated seat, allowing the pelvic alignment that is crucial for the adoption of an adequate posture. METHODS: The articulated seat was set over a ball and socket articulation made of two components, one convex that is fixed in the chair's structure and the other concave, attached to a mobile platform. The property of the articulated seat, to change the pressure distribution in the gluteal region, was tested on 34 typical individuals, without neurological injury, through a measurement system composed by 27 sensors. RESULTS: The significance of the statistic model proposed determined that the articulated seat was capable of altering the pressure distribution in the gluteal region in several positions on the frontal and sagittal planes, in healthy subjects. CONCLUSION: Despite the fact that this equipment is capable of redistributing the pressure in a seating position, future research to examine other parameters such as time of use, the use in subjects with neurological dysfunction, the angle of pelvic inclination, the criterions of indication and non-indication, inter alia, must be conducted to appropriately qualify this device.

INTRODUCTION: When a gas is used for therapy, often the kinetic behavior and their distribution in biological systems is not known, leading to unsatisfactory results for clinical application. The use of ozone in living organisms has been scientifically released worldwide under the name of ozone therapy. The efficacy of this technique is determined primarily by the diffusion of gas within the tissues or fluids and which determines their action in the entire target region. We propose the development of technique to monitoring the O3 dissolved in the biological fluid using an optical device operating in the red-infrared region. METHODS: The recombination of O3 in O2 enables the monitoring of the latter by the measurement of SpO2, and, based on this phenomenon, we propose to use an optical device operating in the red-infrared region to monitoring indirectly the diffusion of O3 in fluids. The system was based on optomechanical arrangement using a capsule containing fluid that was ozonated or oxygenated during the process. A pulse oximeter is a noninvasive device used for continuously measure of SpO2 resulting from the recombination of ozone. RESULTS: The measurements of SpO2 when subjected to ozone and oxygen, showed an increased rate of SpO2 function of time for both cases reaching its peak in 80s and 160s, respectively. The experimental data concerning the SpO2 saturation as a function of time can be fitted by the theoretical model, showing a good correlation between them. CONCLUSION: A technique was developed using an optical device operating in the red-infrared region to monitoring ozone dissolved in biological fluid, showing a simple and effective way to indirectly monitoring the presence of ozone in fluids.

INTRODUCTION: Parcellation of the corpus callosum (CC) in the midsagittal cross-section of the brain is of utmost importance for the study of diffusion properties within this structure. The complexity of this operation comes from the absence of macroscopic anatomical landmarks to help in dividing the CC into different callosal areas. In this paper we propose a completely automatic method for CC parcellation using diffusion tensor imaging (DTI). METHODS: A dataset of 15 diffusion MRI volumes from normal subjects was used. For each subject, the midsagital slice was automatically detected based on the Fractional Anisotropy (FA) map. Then, segmentation of the CC in the midsgital slice was performed using the hierarchical watershed transform over a weighted FA-map. Finally, parcellation of the CC was obtained through the application of the watershed transform from chosen markers. RESULTS: Parcellation results obtained were consistent for fourteen of the fifteen subjects tested. Results were similar to the ones obtained from tractography-based methods. Tractography confirmed that the cortical regions associated with each obtained CC region were consistent with the literature. CONCLUSIONS: A completely automatic DTI-based parcellation method for the CC was designed and presented. It is not based on tractography, which makes it fast and computationally inexpensive. While most of the existing methods for parcellation of the CC determine an average behavior for the subjects based on population studies, the proposed method reflects the diffusion properties specific for each subject. Parcellation boundaries are found based on the diffusion properties within each individual CC, which makes it more reliable and less affected by differences in size and shape among subjects.

INTRODUCTION: Patient monitoring will tend to decline in the coming years due to a shortage of physical and human resources in hospitals. Therefore, several studies define alternatives to improve patient monitoring using wireless networks. In these studies, a wireless network is used to transfer data generated by medical sensors without interacting with the traffic in the data network of the hospital. However, this approach should be avoided because there are demands for integration between user applications and patient monitoring. Therefore, this paper defines a patient monitoring system, called Wi-Bio, directed to the establishment of IEEE 802.11 networks that allows traffic generated by user applications. METHODS: The formal validation of Wi-Bio was made through the design of Petri nets, and performance analysis was performed through simulations of the Network Simulator 2 tool. The adoption of this approach is justified by the fact that Petri nets allow verification of logical correctness of the designed systems, while simulations allow behavioral analysis of Wi-Bio in overload scenarios where many patients are monitored. RESULTS: The results confirmed the validity of the designed Petri nets and showed that Wi-Bio is able to accomplish the temporal goals imposed by medical sensors, thereby promoting efficient integration of traffic present in the data network and the patient monitoring network. CONCLUSION: As described, Wi-Bio fulfilled its objectives and motivates future studies aimed at complementing the obtained results.

INTRODUCTION: The rupture of atherosclerotic plaques causes millions of death yearly. It is known that the kind of predominant tissue is associated with its dangerousness. In addition, the mechanical properties of plaques have been proved to be a good parameter to characterize the type of tissue, important information for therapeutic decisions. METHODS: Therefore, we present an alternative and simple way to discriminate tissues. The procedure relies on computing an index, the ratio of the plaque area variation of a suspecting plaque, using images acquired with vessel and plaques, pre and post-deformation, under different intraluminal pressure. Numerical phantoms of coronary cross-sections with different morphological aspects, and simulated with a range of properties, were used for evaluation. RESULTS: The outcomes provided by this index and a widely used one were compared, so as to measure their correspondence. As a result, correlations up to 99%, a strong agreement with Bland-Altman and very similar histograms between the two indices, have shown a good level of equivalence between the methods. CONCLUSION: The results demonstrated that the proposed index discriminates highly lipidic from fibro-lipidic and calcified tissues in many situations, as good as the widely used index, yet the proposed method is much simpler to be computed.

INTRODUCTION: Studies have shown increases in airway opening pressure (Pao) swings and work of breathing (WOB) by different continuous positive airway pressure (CPAP) devices at rest, but few address this issue during exercise. The aim of the present work was to analyze the imposed WOB (WOBi), the apparent resistance (Rapp) and swings of Pao (deltaP) of 3 CPAP assemblies at simulated exercise conditions. METHODS: The CPAP measures were obtained from: a commercial CPAP (Assembly 1), a high flow CPAP (Assembly 2) and the parallel association of these devices (Assembly 3). In each assembly the spring-loaded positive end-expiratory pressure (PEEP) valve was set to fully opened (mode A) or at the same CPAP pressure (mode B). The exercise protocol simulation, performed manually by a calibrated syringe and a metronome, employed a respiratory frequency of 30 bpm, tidal volume of 2.7 L and inspiratory-to-expiratory ratio of 1. The setups were evaluated at CPAP settings of 5, 10 and 15 cmH2O. RESULTS: The lowest deltaP as well as Rapp and WOBi were obtained with Assembly 3 in mode A with an adjusted CPAP of 10 cmH2O (deltaP=8.1 (0.5) cmH2O, WOBi=1.4 (0.14) cmH2O/L/s, Rapp= 1.3 (0.07) J/s) showed as median (interquartile range). CONCLUSION: For the conditions studied, the best CPAP setup was obtained with mode A.

INTRODUCTION: This paper presents a simulation for evaluation of the scattered radiation components produced in a gamma camera PARK using Monte Carlo code SIMIND. It simulates a whole body study with MDP (Methylene Diphosphonate) radiopharmaceutical based on Zubal anthropomorphic phantom, with some spinal lesions. METHODS: The simulation was done by comparing 3 configurations for the detected photons. The corresponding energy spectra were obtained using Low Energy High Resolution collimator. The parameters related with the interactions and the fraction of events in the energy window, the simulated events of the spectrum and scatter events were calculated. RESULTS: The simulation confirmed that the images without influence of scattering events have a higher number of valid recorded events and it improved the statistical quality of them. A comparison among different collimators was made. The parameters and detector energy spectrum were calculated for each simulation configuration with these collimators using 99mTc. CONCLUSION: The simulation corroborated that LEHS collimator has higher sensitivity and HEHR collimator has lower sensitivity when they are used with low energy photons.