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Introduction Thermography is a surface thermal radiation measurement technique whose application has been expanding in the healthcare field. The unhealed wound is a serious public health problem because it intervenes in the quality of life of patients and may cause emotional and psychological losses. The wound temperature can provide quantitative data that allow for the healing process to be monitored. The aim of this study was to verify whether thermography can be used as a method to evaluate the healing of pressure ulcers. Methods Eight participants with sacral pressure ulcers were recruited and randomly divided into two groups: A (control) and B (experimental). Both groups received standard treatment for a period of four weeks, which consisted of a daily cleaning of the pressure ulcers with physiological saline (sodium chloride 0.9%) followed by an alginate hydrogel dressing. The group B received light-emitting diode (LED) phototherapy in addition to standard treatment, three times a week, yielding a total of 12 sessions. Photographs and thermograms of each pressure ulcer were obtained in all sessions in both groups. Results Pressure ulcers treated with LED phototherapy were healed. The pressure ulcer area of group B decreased over the 12 treatment sessions, whereas the pressure ulcer area of group A increased. The ulcer temperature of group B was higher than that of group A during the treatment (temperature difference up to 7.6%). Discussion The present study suggests a relationship between the temperature and area of pressure ulcers and proposes thermography as an adjunctive method for the evaluation of healing processes.

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Introduction The colorectal cancer is a major health problem worldwide. Histology is considered the gold standard for differential diagnosis. However, it depends on the observer's experience, which can lead to discrepancies and poor results. Spectroscopic imaging by Fourier transform infrared (FTIR) is a technique that may be able to improve the diagnosis, because it is based on biochemical differences of the structural constituents of tissue. Therefore, the main goal of this study was to explore the use of FTIR imaging technique in normal colon tissue, colorectal adenoma, and adenocarcinoma in order to correlate their morphological structures with their biochemical imaging. Methods Samples were collected from normal (n = 4), adenoma (n = 4), and adenocarcinoma human colorectal tissue (n = 4) from patients undergoing colonoscopy or surgical resection of colon lesions. The samples were sectioned with a cryostat in sequential sections; the first slice was placed on CaF2 slide and the second slice was placed on glass slide for histological analysis (HE staining). The cluster analyses were performed by the software Cytospec (1.4.02)®. Results In normal samples, biochemical analysis classified six different structures, namely the lamina propria of mucous glands (epithelial cells and goblet cells), central lumen of the gland, mucin, and conjunctive tissue. In samples with adenoma and adenocarcinoma, altered regions could also be identified with high sensitivity and specificity. Conclusion The results of this study demonstrate the potential and viability of using infrared spectroscopy to identify and classify colorectal tissues.

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Introduction Muscle activity in the aquatic environment was investigated using electromyographic analyses. The physical properties of water and the resistance used may influence the response of the muscle during exercise. The objective of this study was to evaluate the electrical activity in water and on the floor during flexion and knee extension exercises with and without load and aimed at understanding the muscular response while performing resistance exercises in water. Methods The sample consisted of 14 volunteers between 18 and 35 years old who were subjected to active exercises involving knee flexion and extension with and without load on the floor and in water. Electromyography was performed during the movement. Results A significant increase was found in the electrical activity of the rectus femoris muscle during exercises on the floor. The biceps femoris muscle showed increased electromyographic activity when resistance was used. A significant increase was found in the electrical activity of the rectus femoris muscle compared with exercises with and without load and the moment of rest in immersion. The electrical activity of the rectus and biceps femoris muscles was reduced in exercises with load and without load in a therapy pool compared with on the floor. Conclusion There was a reduction of the electromyographic activity in the aquatic environment compared with that on the ground, which could be attributed to the effects from hot water. Therefore, it is believed that resistance exercises can be performed early in a therapy pool, which will facilitate the prevention and treatment of musculoskeletal disorders.

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Introduction It is well known that Parkinson’s disease is related to a deficit of dopamine (DA) in the region of the brain called the corpus striatum. The aim of this work is to demonstrate the possibility of in vitro closed-loop control of the DA concentration levels. Methods By applying the electrochemical technique of fast scan cyclic voltammetry (FSCV), the measured values were compared with previously selected ones, and the system made decisions to control infusion pumps by dynamically adjusting the DA concentration in a continuous flow injection cell. Low-cost hardware was used for the acquisition and control signals (Arduino board), whereas for processing the collected data, graphical programming software (LabView) was used. Results The resolution of the system was approximately 0.4 µmol/L, with a time correction of the concentration adjustable between 1 and 90 seconds. The system allowed control of the DA concentration between 1 and 10 µmol/L with an error of approximately +/– 0.8 µmol/L. Conclusion Although designed to control the DA concentration, the system could be used to control, within the range of the developed FSCV, the concentration of other substances or to turn on brain stimulators. These results encourage the possibility of using the system in clinical studies (in vivo).

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Introduction According to the Global TB control report of 2013, “Tuberculosis (TB) remains a major global health problem. In 2012, an estimated 8.6 million people developed TB and 1.3 million died from the disease. Two main sputum smear microscopy techniques are used for TB diagnosis: Fluorescence microscopy and conventional microscopy. Fluorescence microscopy is a more expensive diagnostic method because of the high costs of the microscopy unit and its maintenance. Therefore, conventional microscopy is more appropriate for use in developing countries. Methods This paper presents a new method for detecting tuberculosis bacillus in conventional sputum smear microscopy. The method consists of two main steps, bacillus segmentation and post-processing. In the first step, the scalar selection technique was used to select input variables for the segmentation classifiers from four color spaces. Thirty features were used, including the subtractions of the color components of different color spaces. In the post-processing step, three filters were used to separate bacilli from artifact: a size filter, a geometric filter and a Rule-based filter that uses the components of the RGB color space. Results In bacillus identification, an overall sensitivity of 96.80% and an error rate of 3.38% were obtained. An image database with 120-sputum-smear microscopy slices of 12 patients with objects marked as bacillus, agglomerated bacillus and artifact was generated and is now available online. Conclusions The best results were obtained with a support vector machine in bacillus segmentation associated with the application of the three post-processing filters.

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Introduction Decomposition of electromyography (EMG) signals into the constituent motor unit action potentials (MUAPs) can allow for deeper insights into the underlying processes associated with the neuromuscular system. The vast majority of the methods for EMG decomposition found in the literature depend on complex algorithms and specific instrumentation. As an attempt to contribute to solving these issues, we propose a method based on a bank of matched filters for the decomposition of EMG signals. Methods Four main units comprise our method: a bank of matched filters, a peak detector, a motor unit classifier and an overlapping resolution module. The system’s performance was evaluated with simulated and real EMG data. Classification accuracy was measured by comparing the responses of the system with known data from the simulator and with the annotations of a human expert. Results The results show that decomposition of non-overlapping MUAPs can be achieved with up to 99% accuracy for signals with up to 10 active motor units and a signal-to-noise ratio (SNR) of 10 dB. For overlapping MUAPs with up to 10 motor units per signal and a SNR of 20 dB, the technique allows for correct classification of approximately 71% of the MUAPs. The method is capable of processing, decomposing and classifying a 50 ms window of data in less than 5 ms using a standard desktop computer. Conclusion This article contributes to the ongoing research on EMG decomposition by describing a novel technique capable of delivering high rates of success by means of a fast algorithm, suggesting its possible use in future real-time embedded applications, such as myoelectric prostheses control and biofeedback systems.

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Introduction The rupture of the anterior cruciate ligament (ACL) is the most common type of knee injury. Reconstructive surgery is the ‘gold standard’ treatment. During the immediate post-operative period, the fixation of the graft is entirely dependent on the ability of the grafted implant to be secured inside the bone tunnel under the cyclical loads associated with daily tasks. Poor fixation can lead to graft slippage, thus impairing the healing and integration of the graft. The aim of this study was to evaluate the biomechanical performance of tendon graft fixation devices with metallic and bioabsorbable interference screws. Methods Twenty ACL reconstructions were carried out in porcine tibias using deep flexor tendons to fix 9 × 20 mm metallic (n=10) and PLLA 70/30 bioabsorbable screws (n=10). To verify the ability of a construct to resist immediate postoperative (PO) rehabilitation protocols for immediate load bearing, a cyclic loading test was applied with 50-250 N of tensile force at 1 Hz for 1000 cycles, and the displacement was measured at 10, 50, 100, 500 and 1000 load cycles to quantify the slippage of the graft during the test. After the cyclic loading test, a single-cycle load-to-failure test was applied. Results The slippage of the graft using metallic screws did not differ (P = 0.616) from that observed when using bioabsorbable screws. Conclusion The results obtained in this experiment indicate that metallic screws may promote a similar amount of graft slippage during low cyclic loading as bioabsorbable screws. Additionally, there was no difference in the biomechanical performance of these two types of screws during high failure loads.

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Introduction Modern transfemoral knee prostheses are designed to offer comfort and self-confidence to amputees. These prostheses are mainly based upon either a passive concept, with a damping system, or an active computational intelligent design to control knee motion during the swing phase. In Brazil, most lower extremity amputees are unable to afford modern prostheses due to their high cost. In this work, we present the conception, design and development of a low-cost intelligent prosthesis for one-sided transfemoral amputees. Methods The concept of the prosthesis is based on a control system with sensors for loads, which are installed on the amputee’s preserved leg and used as a mirror for the movement of the prosthesis. Mechanical strength analysis, using the Finite Element Method, electromechanical tests for the sensors and actuators and verification of data acquisition, signal conditioning and data transferring to the knee prosthesis were performed. Results The laboratory tests performed showed the feasibility of the proposed design. The electromechanical concept that was used enabled a controlled activation of the knee prosthesis by the two load cells located on the shoe sole of the preserved leg. Conclusions The electromechanical design concept and the resulting knee prosthesis show promising results concerning prosthesis activation during walking tests, thereby showing the feasibility of a reduced manufacturing cost compared to the modern prostheses available on the market.

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Introduction The lack of a terminology to compare medical devices together with the arbitrary and opaque nature of product registration systems are major obstacles to a more informed decision process regarding the use and acquisition of new medical devices. This paper describes the systematization of information to help in the identification of similar cardiovascular implantable devices. Methods The systematization was developed in four stages: definition of the technical attributes of each device group; classification of a sample of devices; implementation of the proposed systematization in Protégé; and evaluation of the application. The systematization dealt with a set of common attributes – indication of use, anatomic location, manufacturer, device model and lifetime; and a set of attributes specific for each type of device. Results The systematization was performed by means of a hierarchy of classes with the respective properties in Protégé, which support three basic functions: data entry, query, and maintenance. 38 queries were designed to allow the identification of similar devices according to their technical characteristics. The users’ evaluation showed that the application fulfilled the requirements to monitor the price of these devices on the market. Conclusions Protégé was a useful tool for the systematization of cardiovascular implantable devices that can be used for the post-market vigilance of medical device safety. To better fulfill this aim, other attributes may be incorporated to better characterize the safety aspects of these devices.

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Introduction Intraoral film processing can be performed manually using chambers manufactured from opaque material to prevent light from entering and consequently blurring images. The aim of this study was to evaluate whether portable darkrooms used in offices, clinics and educational institutions prevent the entry of light during the processing of intraoral films. Methods To this end, tests were carried out and images were analyzed by measuring the optical base-plus-fog densities (ODs) upon imaging. Results Review of the OD measurements revealed that in 70.7% of the evaluated manual portable revelation cameras, the base-plus-veil density of intraoral films was not in accord with that of the protocol reference. Discussion The results of this work can be used to identify chambers that are commonly exposed to light from fluorescent lamps and solar lighting.