The diagnosis and monitoring of diabetic foot lesions present a substantial challenge, with traditional techniques susceptible to inaccuracies and potential medical complications due to manual handling. To address this, we introduce a novel methodology that combines computer vision methodologies and advanced transformer-based technologies, specifically Meta’s Segment Anything Model (SAM). Our approach starts with lesion identification via YOLOv5, followed by segmentation utilizing superpixels within the area of interest and the creation of feature vectors. This process enables classification through logistic regression to discern between healthy and damaged skin superpixels. Following this, we integrate the bounding boxes, the pinpointed locations, and the original image as prompts for the SAM model to conduct a final comprehensive segmentation. Our methodology, evaluated using a sample of 83 lesion images, outperformed other state-of-the-art methods, with an Intersection over Union (IoU) of 94.10% and a Dice Similarity Coefficient (DSC) of 96.90%. Hence, the combination of conventional machine learning techniques with cutting-edge models like SAM can yield to precise results while ussing less computational resources when compared to the fine-tuning of advanced models like MedSAM.

MODS, an assay for diagnosis of tuberculosis and drug-susceptibility, is based in the microscopic observation of the characteristic cords of Mycobacterium tuberculosis colonies grown in liquid media. An inverted optical microscope (100× magnification) is required to observe and interpret MODS cultures. Unfortunately, the cost of commercial inverted microscopes is not affordable in low resource settings. To perform a diagnosis of tuberculosis using the MODS assay, images with modest quality are enough for proper interpretation. Therefore, the use of a high cost commercial inverted optical microscope is not indispensable. In this study, we designed a prototype of an optical inverted microscope created by 3D-printing and based on a smartphone. The system was evaluated with 226 MODS TB positive and 207 MODS TB negative digital images. These images were obtained from 10 sputum samples MODS positive and 10 sputum samples MODS negative. The quality of all images was assessed by a qualified technician, in terms of adequacy to interpret and classify them as positive or negative for tuberculosis. The quality of the images was considered appropriate for MODS interpretation. All the 20 samples were correctly classified (as TB positive/negative) by reading with the prototype 3D-printed inverted microscope.

Cough is a characteristic symptom of tuberculosis, is the main cause of transmission, and is used to assess treatment response. We aimed to identify the best measure of cough severity and characterize changes during initial tuberculosis therapy. We conducted a prospective cohort of recently diagnosed ambulatory adult patients with pulmonary tuberculosis in two tertiary hospitals in Lima, Peru. Pre-treatment and five times during the first two months of treatment, a vibrometer was used to capture 4-hour recordings of involuntary cough. A total of 358 recordings from 69 participants were analyzed using a computer algorithm. Total time spent coughing (seconds per hour) was a better predictor of microbiologic indicators of disease severity and treatment response than the frequency of cough episodes or cough power. Patients with prior tuberculosis tended to cough more than patients without prior tuberculosis, and patients with tuberculosis and diabetes coughed more than patients without diabetes co-morbidity. Cough characteristics were similar regardless of HIV co-infection and for drug-susceptible versus drug-resistant tuberculosis. Tuberculosis treatment response may be meaningfully assessed by objectively monitoring the time spent coughing. This measure demonstrated that cough was increased in patients with TB recurrence or co-morbid diabetes, but not because of drug resistance or HIV co-infection.

ABSTRACT Background In Peru, tuberculosis (TB) is perceived as a nutritional disease. This perception, alongside factors including household food insecurity, may drive the food choices of people with TB and influence treatment outcomes. Objectives The objective of this qualitative study was to explore drivers of food choice among adults recently diagnosed with TB. Methods The study was conducted between April and December 2016 in the Huaycán district of Lima, Peru. Structured questionnaires were administered to 39 adults with TB at the time of diagnosis and after 1 mo of treatment to characterize food security and socioeconomic status. At 1 mo of treatment, 24-h dietary recalls, enhanced by recipes obtained from local street vendors, were administered to examine patterns of food consumption and determine mean daily intake of macro- and micronutrients. Among a subset of 9 participants, in-depth interviews were used to explore dietary beliefs and food choices associated with TB. Results Overall, 13.2% of participants were underweight at baseline, and 10.5% were overweight. At 1 mo of treatment, the mean caloric intake was 600 kcal/d over what was needed to maintain their current weight. Most of these additional kilocalories came from carbohydrates. Patients made active efforts to improve their diets during treatment, and were both receptive to, and actively sought out, nutritional advice. However, many patients reported significant unnecessary spending on questionable commercial products, such as expensive natural remedies and nutritional supplements. Conclusions The perceived connection between TB and diet creates both opportunities and challenges for treatment providers. Nutritional counseling provided through the national TB program should promote dietary quality through foods that are locally available, inexpensive, and aligned with cultural perceptions of health and wellness.

The present work develops a MOS-based e-nose with sensors modified with zeolite Y. For this purpose, the following SnO2 doped with Pd and/or Pt have been prepared: M1 ((0.25 Pd/0.75 Pt)/SnO2), M2 ((0.50 Pd/0.50 Pt)/SnO2), M3 ((0.75 Pd/0.25 Pt)/SnO2), Pd/SnO2, and Pt/SnO2, at the total concentrations of the noble metals of 0.1% and 0.2% for use in gas sensors and be part of the electronic nose. Then, the sensors were assembled with the oxides using the screen printing method. Different electronic noses of four sensors were prepared by combining tin oxides doped with palladium and/or platinum and zeolite Y. The physicochemical characterization of oxides using FRX, FTIR, sorption of N2, and RAMAN has been performed. Measurements for the detection of wine volatile compounds such as ethanol, methanol, 1-phenyl ethanol, propionic acid, and acetic acid were carried out with these sensors located in a gas chamber and using a program that includes the Labview software, which serves to automate the sensing process. It was found that the sensors modified with zeolite were the ones that in general had higher detections of volatile compounds and PCAs showed positive correlations only for ethanol and the mixture of ethanol at 12% and methanol at 3%. This is related to better detection of these sensors.

Introduction:Tuberculosis (TB) is a significant cause of morbidity and mortality worldwide. The patient compliance with the long treatment regimens is essential for successful eradication. Pyrazinamide (PZA) shortens these regimens from 9 to 6 months, and therefore, improves treatment completion rates. Although PZA is a first-line medication for the treatment of TB, no simple or reliable assay to determine PZA resistance is yet available. In the presence of PZA, only susceptible Mycobacterium tuberculosis strains release pyrazinoic acid (POA). Therefore, the measurement and quantification of released POA is an indicator of PZA resistance.Methods:Two electrochemical sensors were constructed and tested with alternative working electrodes in conjunction with a portable potentiostat to measure the current produced when a potential difference of 2 V is applied to varying concentrations of POA in controlled solutions.Results:The large (13.2 mm) electrochemical sensor was able to detect POA at a minimum concentration of 40 μM to a statistically significant level (P = 0.0190). Similar graphical trends were obtained when testing the electrochemical sensor in the supernatant of a negative microscopic observation drug susceptibility assay culture, irrespective of the presence of PZA.Conclusion:Inexpensive and reusable electrochemical sensors with a portable potentiostat are a promising tool for the detection of POA, a biomarker of PZA susceptible M. Tuberculosis.

BACKGROUND: Cough frequency, and its duration, is a biomarker that can be used in low-resource settings without the need of laboratory culture and has been associated with transmission and treatment response. Radiologic characteristics associated with increased cough frequency may be important in understanding transmission. The relationship between cough frequency and cavitary lung disease has not been studied. METHODS: We analyzed data in 41 adults who were HIV negative and had culture-confirmed, drug-susceptible pulmonary TB throughout treatment. Cough recordings were based on the Cayetano Cough Monitor, and sputum samples were evaluated using microscopic observation drug susceptibility broth culture; among culture-positive samples, bacillary burden was assessed by means of time to positivity. CT scans were analyzed by a US-board-certified radiologist and a computer-automated algorithm. The algorithm evaluated cavity volume and cavitary proximity to the airway. CT scans were obtained within 1 month of treatment initiation. We compared small cavities (<= 7 mL) and large cavities (> 7 mL) and cavities located closer to (<= 10 mm) and farther from (> 10 mm) the airway to cough frequency and cough cessation until treatment day 60. RESULTS: Cough frequency during treatment was twofold higher in participants with large cavity volumes (rate ratio [RR], 1.98; P = .01) and cavities located closer to the airway (RR, 2.44; P = .001). Comparably, cough ceased three times faster in participants with smaller cavities (adjusted hazard ratio [HR], 2.89; P = .06) and those farther from the airway (adjusted HR, 3.61;, P = .02). Similar results were found for bacillary burden and culture conversion during treatment. CONCLUSIONS: Cough frequency during treatment is greater and lasts longer in patients with larger cavities, especially those closer to the airway.

Background. Cough is the major determinant of tuberculosis transmission. Despite this, there is a paucity of information regarding characteristics of cough frequency throughout the day and in response to tuberculosis therapy. Here we evaluate the circadian cycle of cough, cough frequency risk factors, and the impact of appropriate treatment on cough and bacillary load.Methods. We prospectively evaluated human immunodeficiency virus-negative adults (n = 64) with a new diagnosis of culture-proven, drug-susceptible pulmonary tuberculosis immediately prior to treatment and repeatedly until treatment day 62. At each time point, participant cough was recorded (n = 670) and analyzed using the Cayetano Cough Monitor. Consecutive coughs at least 2 seconds apart were counted as separate cough episodes. Sputum samples (n = 426) were tested with microscopic-observation drug susceptibility broth culture, and in culture-positive samples (n = 252), the time to culture positivity was used to estimate bacillary load.Results. The highest cough frequency occurred from 1 pm to 2 pm, and the lowest from 1 am to 2 am (2.4 vs 1.1 cough episodes/hour, respectively). Cough frequency was higher among participants who had higher sputum bacillary load (P < .01). Pretreatment median cough episodes/hour was 2.3 (interquartile range [IQR], 1.2-4.1), which at 14 treatment days decreased to 0.48 (IQR, 0.01.4) and at the end of the study decreased to 0.18 (IQR, 0.0-0.59) (both reductions P < .001). By 14 treatment days, the probability of culture conversion was 29% (95% confidence interval, 19%-41%).Conclusions. Coughs were most frequent during daytime. Two weeks of appropriate treatment significantly reduced cough frequency and resulted in one-third of participants achieving culture conversion. Thus, treatment by 2 weeks considerably diminishes, but does not eliminate, the potential for airborne tuberculosis transmission.

Digital manufacturing (DM) offers fast prototyping capabilities and great versatility to configure countless architectures at affordable development costs. Autonomous lab-on-a-chip (LOC) devices, conceived as only disposable accessory to interface chemical sensing to cell phones, require specific features that can be achieved using DM techniques. Here we describe stereo-lithography 3D printing (SLA) of optical components and unibody-LOC (ULOC) devices using consumer grade printers. ULOC devices integrate actuation in the form of check-valves and finger pumps, as well as the calibration range required for quantitative detection. Coupling to phone camera readout depends on the detection approach, and includes different types of optical components. Optical surfaces can be locally configured with a simple polishing-free post-processing step, and the representative costs are 0.5 US$/device, same as ULOC devices, both involving fabrication times of about 20 min.

El objetivo principal fue encontrar cómo ciertos parámetros o factores fisicoquímicos del carbón activado pueden influir en la capacidad de adsorción de tres adsorbatos: fenol, ácido benzoico y ácido salicílico. Se emplearon dos métodos de análisis multivariado de datos: análisis principal de mínimos cuadrados (PLS) y regresión de componentes principales (PCR). El método de PLS mostró una mejor concordancia entre los valores estimados y experimentales. Usando este método, se formularon ecuaciones para predecir la capacidad de remoción de cada adsorbato. Usando PLS fue posible estimar la capacidad de adsorción del ácido benzoico, ácido salicílico y fenol con un error estándar de validación menor al 6%. Así se predijo que la acidez superficial es el parámetro más importante del carbón activado para adsorber compuestos aromáticos.

An electronic nose for the detection of alcohols, easy to use and inexpensive as compared to traditional electronic noses, was developed. This nose is based on four SnO2 gas sensors (two commercial and two home-made), an irregular pneumatic system, hardware and a software for data acquisition and a software for pattern recognition. The nose behavior and the working conditions with vapor samples of alcohols (methanol, ethanol, n-butanol and 1-octanol) were evaluated. Alcohols could be detected with the array of prepared sensors and could be also differentiated from each other by using principal component analysis (PCA). The detection order for linear alcohols followed the order: methanol > ethanol > n-butanol > 1octanol. It was also found that by using PCA and performing a standardization of data in software pattern recognition so, the total variance of such information increases from 76% up to 85%. This result confirms that a simple and inexpensive nose can rank well the tested samples.

General enzymatic detection with cell phones using 3D printed fluidics and optics.

Se desarrolló una nariz electrónica que permite la detección de alcoholes de manera sencilla y económica en comparación con las narices electrónicas tradicionales. Está basada en cuatro sensores de gas de SnO2 (dos comerciales y dos fabricados en el laboratorio), un sistema neumático irregular, un hardware y software para adquisición de datos y un software de reconocimiento de patrones. Se evaluó el comportamiento de la nariz y las condiciones de trabajo con muestras de vapor de alcoholes (metanol, etanol, n-butanol y 1-octanol) y se determinó que los alcoholes se pueden detectar con el arreglo de sensores preparado y pueden diferenciarse entre sí haciendo uso del análisis estadístico de componentes principales (PCA). El orden de detección encontrado para los alcoholes lineales fue el siguiente: metanol > etanol > n-butanol > 1-octanol. Se encontró también que haciendo uso del análisis de componentes principales (PCA) y realizando una normalización de los datos en el software de reconocimiento de patrones, la varianza total de las muestras también aumenta del 76% al 85%. Esto demuestra que una nariz simple y económica puede clasificar bien las muestras evaluadas.

Introduction Cough is a key symptom of tuberculosis (TB) as well as the main cause of transmission. However, a recent literature review found that cough frequency (number of coughs per hour) in patients with TB has only been studied once, in 1969. The main aim of this study is to describe cough frequency patterns before and after the start of TB treatment and to determine baseline factors that affect cough frequency in these patients. Secondarily, we will evaluate the correlation between cough frequency and TB microbiological resolution. Methods This study will select participants with culture confirmed TB from 2 tertiary hospitals in Lima, Peru. We estimated that a sample size of 107 patients was sufficient to detect clinically significant changes in cough frequency. Participants will initially be evaluated through questionnaires, radiology, microscopic observation drug susceptibility broth TB-culture, auramine smear microscopy and cough recordings. This cohort will be followed for the initial 60 days of anti-TB treatment, and throughout the study several microbiological samples as well as 24 h recordings will be collected. We will describe the variability of cough episodes and determine its association with baseline laboratory parameters of pulmonary TB. In addition, we will analyse the reduction of cough frequency in predicting TB cure, adjusted for potential confounders. Ethics and dissemination Ethical approval has been obtained from the ethics committees at each participating hospital in Lima, Peru, Asociación Benéfica PRISMA in Lima, Peru, the Universidad Peruana Cayetano Heredia in Lima, Peru and Johns Hopkins University in Baltimore, USA. We aim to publish and disseminate our findings in peer-reviewed journals. We also expect to create and maintain an online repository for TB cough sounds as well as the statistical analysis employed.