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Resultados da Pesquisa
Item Desenvolvimento de software para análise e simulação de ensaio de tração aplicado na Engenharia Biomédica(Universidade Brasil, 2022) Broggio, João Roberto; Costa, Mardoqueu Martins daThe physical and chemical properties of materials in addition to biological requirements are of fundamental importance in the development of materials with biomedical application, the physical characteristics are obtained mainly by tensile tests, whereas the shape of an implant can be simulated in commercial software, which use these physical characteristics of the materials as parameters to run the simulation algorithm. As normally the shape and dimensions are fixed and with peculiar characteristics, the selection of the material family is limited, and even within the family the materials can be under or over dimensioned. To solve this problem, the application will enable the designer to simulate the project by calculating a characteristic virtual material within the limits of the control variable, using as basis the physical tests of the under and over dimensioned materials. The objective of this thesis is to develop virtual mechanical tests as an aid in the development of biomedical materials, based on results of physical tensile tests, the application can simulate a mechanical test. Nine physical tensile tests were performed in an Emic machine for each of the control variables (Speed and Diameter), which were subdivided into three groups, at speeds of 7, 15 and 22 mm/min on 304 stainless steel, and diameters of 10, 11 and 12 mm on SAE 1020 steel. In the comparison performed between the virtual materials at 15 mm/min and 11 mm diameter, the application proved to be efficient with error lower than 3% when the results were compared to the physical test on a universal machine and the virtual test on commercial software. The developed application besides graphically locating the points of interest on stress/strain curves also produces mathematically a virtual biomaterial, passive of simulation in commercial software with shapes and dimensions of an implant or biocomponent.Item Estudo da composição bioquímica de unhas para o diagnóstico de Diabetes Mellitus por Espectroscopia Raman(Universidade Brasil, 2021) Veras, Juscélia Maria de Moura Feitosa; Fávero, Priscila Pereira; Garcia, Lívia Assis; Martin, Airton AbrahãoThe growth of Diabetes Mellitus (DM) is a public health problem with greater prevalence in developing countries. The estimated prevalence of diabetes in people aged 20-79 years has increased from 151 million to 463 million today, with a total forecast of 700 million diabetics by 2045. Hence the importance of an early, non invasive, practical and low-cost diagnosis for DM detection and monitoring. Type II diabetes mellitus (DM2) gradually changes the intrinsic material properties of tissues and their structural integrity, and prolonged hyperglycemia can cause chronic damage to the quality of these tissues. No technique is available to clinically assess altered tissue quality in diabetic patients. However, recent studies suggest that the quality of the nail plate has great potential to assess the secondary complications of DM. Thus, this study aimed to determine the biochemical characteristics of nails of individuals with DM2 through confocal Raman spectroscopy, in addition to identifying the spectral signatures and new DM2 markers in nails. This study is a multicenter clinical study (Universidade Brasil - SP and Fundação Municipal de Saúde de Teresina/PI), comparative, randomized and instrumental with a qualitative approach. For the research, 30 healthy volunteers and 30 DM2 were selected. The collection and evaluation of fragments in the distal region of the nail was carried out. The results obtained demonstrated alterations in different biochemical components, such as: proteins, lipids, amino acids, advanced glycation end products, in addition to alterations in the disulfide bridges, which are important in the stabilization of keratin in the nails. Therefore, due to the possibility of acquiring such information through the evaluation of nails, a simple and easy-to-acquire material, this becomes an important material for analysis, allowing DM and its complications to be detected quickly. In addition, the study also demonstrated that the assessment of nails by confocal Raman spectroscopy is an important technique, which, together with the assessment of nails, can become an important tool in the diagnosis and follow-up of diabetic patients.Item Desenvolvimento de biossensor eletroquímico para detecção de lactato(Universidade Brasil, 2021) Torres, Samuel Guerra; Costa, Adriana Pavinatto da; Costa, Mardoqueu Martins daThe development of new sensory platforms is of great interest to the field of biosensors, especially those with low cost and high reproducibility characteristics. In this context, the present study aimed at the production and characterization of a biosensor platform composed of films produced by the physical adsorption self assembly technique (Layer-by-Layer - LbL) using chitosan and AuNps@PTS (gold nanoparticles stabilized with PTS polymer – a sulphonated polythiophene derivative). Subsequently, the platform formed was used for immobilization of the enzyme lactate oxidase (LOx) and detection of lactate. The films were formed in different numbers of bilayers and characterized by spectroscopic measurements of ultraviolet absorption (UV-Vis) and fluorescence, and electrochemical measurements. The LOx enzyme was immobilized on two LbL film bilayers through dripping and subsequent cross linking performed with the addition of glutaraldehyde. The detection of lactate was performed through cyclic voltammetry (VC) measurements on standard samples. The results show that film growth was relatively homogeneous, and until the fourth bilayer the absorption intensity increased linearly with the number of bilayers. CV measurements showed that the electrode modified with two film bilayers allows greater charge transfer, being the platform chosen for immobilization of the LOx enxima and detection of lactic acid. Voltammograms showed that the presence of the LOx enzyme hinders charge transfer and that its immobilization was effective. Detection measurements show that the developed platform is suitable for detecting lactate, and the analytical signal presented a linear regime between the increase in the anodic current magnitude and the increase in the lactate concentration, in the range of 0.5 to 30 mM of lactate. The platform used was able to detect human sweat lactate at different times and intensities of physical exercise, with detection limits close to those found in the literature.Item Composição química e atividade antimicrobiana de óleos vegetais in natura e ozonizados em Acinetobacter baumannii(Universidade Brasil, 2021) Silva, Wagner Rafael da; Kozusny-Andreani, Dora InésThe study of infection control mechanisms caused by bacteria is a topic of interest to different professionals involved in the hospital environment. This work aimed to investigate the use of vegetable oils as an alternative treatment in the control of these infections. The bactericidal effect of canola, coconut and palm oil, in natura and ozonized oils, was evaluated under Acinetobacter baumannii, a species of bacteria that stands out as an important opportunistic pathogen and is responsible for infections related to the care of health. All the tested oil samples were characterized by the techniques of gas chromatography, I2 and peroxides index, the most altered characteristic under the effect of the ozonation process, passing from undetectable in the samples of in natura oils to the fractions 125,7 ± 0,2; 422,4 ± 0,2 and 434,8 ± 0,2 meq/Kg of Na2S2O3 for canola oil, coconut and ozonized palm oil. The reduction of microbial load in A. baumannii strains was 93,5, 71,6 and 85,9% for canola, coconut and in natura palm oils, respectively, and 96,2, 93,8 and 91,0% for the oils of canola, coconut and ozonized palm oil, respectively. In addition, the efficiency in the inhibition time of A. baumanni showed that ozonized oils present immediate bactericidal action, where their bacterial count in 10 min equates to the results of in natura oils after 30 min of incubation. These results revealed that the oils tested can be used in the control of bacterial infections and the ozonization of these oils potentiates the bactericidal action. The results showed, however, that the comparison between the microbial counts of in natura and ozonized oils did not point significant differences, since all the resulting p-values were higher than the level of significance adopted for the comparative test. A similar result was found in the comparison among ozonized oils in terms of microbial count, that is, there were no significant differences among microorganism counts when the different types of ozonized oils were compared.Item Efeitos da indução de estresse mental na variabilidade da frequência cardíaca em atletas de Badminton(Universidade Brasil, 2021) Carvalho, Jane Maria Silva; Navarro, Ricardo ScarparoThe objective of the study was to analyze the effects of mental stress induction on heart rate variability in Badminton athletes. The study is direct, descriptive, experimental, cross-sectional and quantitative, carried out with the 15 highest ranked in the State of Piauí, by the Brazilian Confederation of Badminton, in January 2019. The sample consisted of 8 women and 7 men, with the average age of 19 years-old (+2.85), where the majority belonged to the main category (53.33%), participated in international competitions (66.66%) in all modalities (80%). The athletes were submitted to a previous anamnesis, measurement of blood pressure (BP), evaluation of HRV and Computerized Stroop Test. The procedures started with the placement of the Polar® H10 transmitter for the evaluation of the HRV in the participants, who went through a 5 min adaptation moment, when their BP was measured. After another 5 minutes of rest and BP measurement again, the Stroop Test of TESTIPACS® was then applied and the HRV evaluation was completed. For the analysis of HRV, the intervals were fragmented into 1 min, so that possible changes in the signals could be observed and only the resting moment and application of the Stroop Test were considered. All procedures were approved by the Ethics and Research Committee of Centro Universitário Uninovafapi (PI) (#3147702). It can be observed that the stressful stimulus promoted an increase in the mean HR and a decrease in the mean of the RR intervals, which suggests a physiological response that reflects the activation of the cardiac autonomic function, also perceived in the reduction of the SDNN, RMSSD, NN50 and pNN50 components. The high stress index during the time of application of the Stroop Test corroborates the values of the increased SNS index. The components of the frequency domain showed an increase in LF and LF/HF and maintenance of HF, while in the results of the Poincaré graph, the values of SD1 and SD2 reduced and the SD2/SD1 ratio increased. In the correlation analyses, it is possible to notice that the performance regarding the reaction time of the Stroop test is directly proportional to the components RMSSD, NN50, pNN50 and to the PNS index, while the stress index is inversely proportional. The other components did not show statistical significance. It is possible to verify that the Stroop Test was able to generate physiological changes with important responses in HRV, but further studies are needed on the stressful effect on athletes, as they are frequently subjected to both physical and mental stress, and that this frequency can lead to long-term cardiac overload.Item Efeitos da fotobiomodulação associada ou não ao Biopolímero de Fibrina Heterólogo no processo de reparo tecidual de lesões cutâneas de ratos diabéticos(Universidade Brasil, 2021) Alexandria, Francisco Eugênio Deusdará de; Tim, Carla Roberta; Assis, LíviaItem Diagnóstico clínico automatizado a partir do uso de métodos de análise multivariada aplicados a sinais de eletrocardiograma(Universidade Brasil, 2020) Zena, Antonio Chavez; Mendes, Thiago de Oliveira; Santos, Laurita dosThis work presents a study of methods applied to pattern recognition of heart rate variability parameters obtained from electrocardiogram (ECG) for the aid of automated clinical diagnosis of various diseases associated with the heart, using multivariate statistical methods and computational machine learning. For this purpose, the electrocardiograms signs of 137 volunteers clinically diagnosed with normal sinus rhythm (NSR), with n = 54 individuals, which will represent the control group, and two clinical conditions formed by individuals with congestive heart failure (CHF), with n = 29 individuals or suppression of cardiac arrhythmia (CAST), with n = 54 individuals, considering these two clinical conditions, such as the case groups. All these signals were obtained from the PhysioNet, which covers a set of real biomedical signals, open source software and from studies consolidated in the literature. A procedure for obtaining characteristic variables of ECG tachograms was described, these variables were modeled by classification approaches of Discriminant Analysis data by Partial Least Squares regression (PLS-DA) and Artificial Neural Networks (ANN), aiming at the diagnosis of two clinical conditions when compared with a control group. Data matrices of variables associated with the time domain, frequency domain and obtained by non-linear methods were considered separately, each one, and all of these in a single data matrix, of statistical parameters associated with heart rate variability. The figures of merit showed that there is a pattern in the behavior of the tachogram parameters that may be used for clinical diagnostic aid. Both congestive heart failure and the classification and prediction of samples belonging to the cardiac arrhythmia suppression were satisfactorily obtained, with an area under the ROC curve close to 0.9. The PLS-DA model demonstrated the best data classification results, where congestive heart failure was diagnosed with rates of 90.9% of sensitivity and selectivity of 85.7% and suppression of cardiac arrhythmia was predicted with rates of 75.0% of sensitivity and 100.0 % of selectivity, suggesting that clinical diagnosis assisting real time and a personalized prognosis can become a reality that will contribute positively to medical practice.Item Características epidemiológicas e moleculares da infecção pelo vírus da imunodeficiência humana em gestantes no Estado do Piauí, Brasil(Universidade Brasil, 2020) Lima Verde, Roseane Mara Cardoso; Pavinatto, Adriana; Costa, Mardoqueu Martins daIt is estimated that, since its discovery in 1981 until the end of 2018, 74.9 million people have been infected with HIV and that 32 million people have died of AIDS-related illnesses since the beginning of the pandemic. Regardind infection in children (up to 13 years old), 84% of cases are due to vertical transmission. In this context, the present study aimed to identify the main epidemiological characteristics of HIV infection in pregnant women attended at a reference maternity hospital in Piauí, northeastern Brazil. This is a prospective study with the participation of 873 pregnant women attended at Maternidade Dona Evangelina Rosa (MDER), carried out between January 2016 and December 2017. For this purpose, samples were collected, epidemiological information and the diagnosis of HIV infection, carried out through anti-HIV-1/2 antibodies tests (Immunoblot HIV-1/2). In addition, syphilis diagnosis (VDRL and Rapid Treponemic Test), LTCD4 count (Flow Cytometry) and Viral Load (PCR-Real Time) counts were performed. Phylogenetic analysis allowed the comparison with other strains in the literature and the presence of resistance mutations. The data were analyzed using the statistical program Statistical Package for the Social Sciences 20.0 (SPSS). For comparative analysis, the chi-square test (2) was used, with a significance level 5% (p <0.05). Of the total participants, 17 samples tested positive for HIV and were genotyped to determine the subtypes. The prevalence of pregnant women with HIV was 1.95%, characterized as housewives, aged 12 to 35 years, heterosexual, with a partner, elementary school, residents of an urban area, own home, and family income of one to two minimum wages. It was found that 41.2% of pregnant womwn had between 0 and 6 consultations; 76% were in the 3rd trimester; 54.3% of deliveries were cesarean; 44.6% were primiparous and that 72.5% of newborns were over 2.5 kg. No statistical significance was observed in the correlations between the HIV-1 viral load and LTCD4 count parameters with the observed behavioral parameters. All HIV-1 seropositive samples were classified as subtype B (100%). DRM were detected for two samples, the PW 300 and PW 815 sequences. In the PW 300 sequence, the L90M mutation was found, while in the PW 815 sequence, L90M and K103N mutations were detected. L90M is a HIV-1 protease inhibitors (IP) resistance mutation classified as highly resistance to the drug nelfinavir and intermediate resistance to indinavir and saquinavir; the K103N mutation is associated with non-nucleoside inhibitors of HIV-1 reverse transcriptase (INNTR) and classified as highly resistant to nelfinavir and nevirapine. In the end, an flowchart for monitoring the health of pregnant women was developed to guide care and comprehensive care for HIV positive pregnant women in the State of Piauí. It is concluded that, in order to reduce the risk factors of the mother-child binomial and vertical HIV transmission, early diagnosis, quantification of viral load, genotyping and a correct decision in choosing the therapeutic scheme are of fundamental importance, thus avoiding the appearance of resistance strains.Item Caracterização de óleo de girassol ozonizado em diferentes tempos usando Espectroscopia de Infravermelho com Transformada de Fourier(Universidade Brasil, 2021) Uebele, Daniela; Santos, Laurita dos; Pessoa, Rodrigo SávioThe estimated number of patients in Brazil and abroad, emphasizes the need for better monitoring and treatment of skin lesions, caused by numerous health problems, in addition to worsening by viral infections, bacteria, fungi and protozoa - the prospect is of increasing cases in developing and underdeveloped countries. This is due to the inefficient treatments offered by hospitals, with an emphasis on public hospitals. These are more than enough reasons to invest time in the analysis of an affordable therapeutic treatment compared to the current ones - such as the use of "ozone therapy". This is recognized and used on 5 continents and is even encouraged and sponsored by the governments and health plans of many countries. One of the safest ways of using ozone in treatments is through the by-products generated in the ozonolysis of vegetable oils, which can act on the skin, leading to the disinfection process, by cell lysis. In this work, the choice was for sunflower oil due to its physicochemical characteristics. The objective is to analyze the chemical structure of ozonized sunflower oil at different times over 90 minutes, without using the temperature control of the ozonolysis reactor. For that, the process of analysis by Fourier transform spectroscopy (FTIR) was used. 9 spectra were collected and analyzed by the deconvolution process, in comparison to the main bands observed by the second derivative. The results show that there was an increase in oil temperature (around 10ºC) during ozonation up to 30min. Three regions of the obtained spectra were analyzed: 3050-2800cm-1 , 1130-1070cm-1 and 1800-800cm-1 . Statistical results show a significant difference between spectral signals, with observance after the time of 20min of the sunflower oil ozonation process, with emphasis on the 1800–1500cm 1 region, which demonstrates the rupture of the double carbon bonds (C=C), breaking the lipid chain, and increasing the CO2 chain and thus reducing HC=CH, observed in the analysis of the spectra. There was a reduction in the intensity of the -CH band of the stretching of the -C=CH fragment above the 3000cm-1 region, an increase in the CH stretching bands of the CH3 groups, a reduction in the intensity of the -C=C- binding stretch and constant intensity of the band stretch -C, and all changes detected by FTIR are in accordance with the Criegee mechanisms. With these observations it can be reiterated how useful FTIR spectroscopy is for the analysis of changes in compounds. Following the studies with the support of collaborators, initial tests of the application of the samples of the ozonized sunflower oil were carried out, extending up to 120 minutes, in cutaneous lesions in ex-vivo in an animal model, using the same analysis process, observing whether there were changes between the spectra. In the statistical analysis, these changes are subtle, not enough to obtain results. For this, it is necessary to analyze in a wider region of the spectrum. It was not possible to obtain evidence of its benefits in the healing process. In need of in-depth studies, considering other factors relevant to the study.Item Aplicações de modelos computacionais de análise de dados biomédicos em plataformas de dispositivos móveis(Universidade Brasil, 2020) Sousa, José Vigno Moura; Almeida, Vilson Rosa de; Costa, Mardoqueu Martins daThis work develops CNNPulmona and CNNCardio, implementations of computational models for optimization of analysis of biomedical data from chest radiography (CXR) and electrocardiogram (ECG), respectively, deployable in mobile device platforms, in addition to a comparison of several methods of signal compression. CNNPulmona is an approach for classifying chest Xray images into three classes: bacterial pneumo nia, viral pneumonia (Covid19 or other type) and healthy lung. Convolutional Neural Networks are used, based on pretrained networks in conjunction with a quantization process, by means of the TensorFlow Lite platform method, thereby reducing the com putational cost. The cascade classification method is used, which makes it possible to divide the classifications into different stages; thus, it was possible to obtain 99.16% ac curacy in the classification of images with suspicion of Covid19. The resulting mobile application program also features a simple and intuitive user interface. In CNNCardio, a new method to classify electrocardiogram signals on mobile devices is proposed, which can classify different arrhythmias according to the EC57 standard of the Asso ciation for the Advancement of Medical Instrumentation. A convolutional neural net work was built, trained and validated with the MITBIH arrhythmia dataset, in which this database has 5 different classes: normal beat, premature supraventricular beat, pre mature ventricular contraction, ventricular beat fusion, normal and unclassifiable beat. After being trained and validated, the model is submitted to a posttraining quantization stage using the TensorFlow Lite conversion method.The results obtained were very sat isfactory, before and after quantization; the convolutional neural network obtained an accuracy of 99%. With the quantization technique, it was possible to obtain a significant reduction in the size of the model, thus enabling the development of the mobile applica tion; this reduction was approximately 90% in relation to the size of the original model. Additionally, the behavior of different signals was compared, when applied to different compression techniques, in order to test and find the best compression techniques for distinct types of biomedical signals, also proving that different types of biomedical sig nals behave distinctly in different types compression of biomedical signals, the results of this comparison of signal compression methods were very satisfactory, demonstrating that different types of compression can be used on signals for better results.