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OBJECTIVE Machine learning algorithms have shown groundbreaking results in neuroimaging. The authors herein evaluated the performance of a newly developed convolutional neural network (CNN) to detect and analyze intracranial aneurysms (IAs) on CTA. METHODS Consecutive patients with CTA studies between January 2015 and July 2021 at a single center were identified. The ground truth determination of cerebral aneurysm presence or absence was made from the neuroradiology report. The primary outcome was the performance of the CNN in detecting IAs in an external validation set, measured using area under the receiver operating characteristic curve statistics. Secondary outcomes included accuracy for location and size measurement. RESULTS The independent validation imaging data set consisted of 400 patients with CTA studies, median age 40 years (IQR 34 years) and 141 (35.3%) of whom were male; 193 patients (48.3%) had a diagnosis of IA on neuroradiologist evaluation. The median maximum IA diameter was 3.7 mm (IQR 2.5 mm). In the independent validation imaging data set, the CNN performed well with 93.8% sensitivity (95% CI 0.87–0.98), 94.2% specificity (95% CI 0.90–0.97), and a positive predictive value of 88.2% (95% CI 0.80–0.94) in the subgroup with an IA diameter ≥ 4 mm. CONCLUSIONS The described Viz.ai Aneurysm CNN performed well in identifying the presence or absence of IAs in an independent validation imaging set. Further studies are necessary to investigate the impact of the software on detection rates in a real-world setting.

Excess adipose tissue is considered one of the main causes of metabolic and cardiovascular diseases. Initially, the adipose tissue was considered the main lipid and energy storage of the organism. Subsequently it was discovered that adipose tissue had other functions such as endocrine, controlling different metabolic and immune processes. Currently, different types of adipose tissue are recognized. The white adipocyte represents the main energy reserve, on the contrary the brown adipocyte is responsible for the oxidation of lipids for thermogenesis. The beige adipocyte originates from the white adipocyte, by a process known as "browning", which leads to lipolysis and thermogenesis. The 3 previous types have recently joined the blue adipocyte, which has a role in liver retinoid homeostasis and the pink adipocyte that participates in lactogenesis and is present in the mammary gland of animals; its role is still unknown in humans. The newly identified hormone Irisin is secreted by the skeletal muscle and promotes browning of white to beige adipose tissue, thus favoring thermogenesis. Another interesting aspect of this hormone is that it represents a connection between muscle activity and lipolysis. The above suggests that Irisin may be the key in the prevention and treatment of obesity.El exceso de tejido adiposo representa una de las principales causas de las enfermedades metabólicas y cardiovasculares. Inicialmente al tejido adiposo se le consideró el almacén de lípidos y energía del organismo. Posteriormente se descubrió que presentaba otras funciones, como la endocrina, controlando diferentes procesos metabólicos e inmunitarios. Por sus características funcionales y estructurales, se reconocen varios tipos de tejido adiposo. El adipocito blanco representa la reserva energética y el adipocito marrón se encarga de la oxidación de los lípidos para la termogénesis. El adipocito beige se origina del adipocito blanco, mediante un proceso que conduce a la lipólisis y la termogénesis. A los anteriores se han sumado el adipocito azul, en el hígado, que interviene en la homeostasis de retinoides, y el adipocito rosa, que participa en la lactogénesis y se ha identificado en la glándula mamaria de animales. La irisina es una hormona secretada principalmente por el músculo esquelético, que promueve el pardeamiento del tejido adiposo blanco a beige, favoreciendo así la termogénesis. Otro aspecto interesante de esta hormona es que representa una conexión entre la actividad muscular y la lipólisis. Por lo anterior, la irisina puede ser una clave en la prevención y el tratamiento de la obesidad.

Funder: NIH U18EB029353, NSF GRFP, Funder: NIH U18EB029353, Funder: NIH R01DE021798, NSF GRFP, Funder: NIH R01DE021798, Implantable bioelectronic devices for the simulation of peripheral nerves could be used to treat disorders that are resistant to traditional pharmacological therapies. However, for many nerve targets, this requires invasive surgeries and the implantation of bulky devices (about a few centimetres in at least one dimension). Here we report the design and in vivo proof-of-concept testing of an endovascular wireless and battery-free millimetric implant for the stimulation of specific peripheral nerves that are difficult to reach via traditional surgeries. The device can be delivered through a percutaneous catheter and leverages magnetoelectric materials to receive data and power through tissue via a digitally programmable 1 mm × 0.8 mm system-on-a-chip. Implantation of the device directly on top of the sciatic nerve in rats and near a femoral artery in pigs (with a stimulation lead introduced into a blood vessel through a catheter) allowed for wireless stimulation of the animals' sciatic and femoral nerves. Minimally invasive magnetoelectric implants may allow for the stimulation of nerves without the need for open surgery or the implantation of battery-powered pulse generators.

OBJECTIVE Machine learning algorithms have shown groundbreaking results in neuroimaging. Herein, the authors evaluate the performance of a newly developed convolutional neural network (CNN) to detect and quantify the thickness, volume, and midline shift (MLS) of subdural hematoma (SDH) from noncontrast head CT (NCHCT). METHODS NCHCT studies performed for the evaluation of head trauma in consecutive patients between July 2018 and April 2021 at a single institution were retrospectively identified. Ground truth determination of SDH, thickness, and MLS was established by the neuroradiology report. The primary outcome was performance of the CNN in detecting SDH in an external validation set, as measured using area under the receiver operating characteristic curve analysis. Secondary outcomes included accuracy for thickness, volume, and MLS. RESULTS Among 263 cases with valid NCHCT according to the study criteria, 135 patients (51%) were male, the mean (± standard deviation) age was 61 ± 23 years, and 70 patients were diagnosed with SDH on neuroradiologist evaluation. The median SDH thickness was 11 mm (IQR 6 mm), and 16 patients had a median MLS of 5 mm (IQR 2.25 mm). In the independent data set, the CNN performed well, with sensitivity of 91.4% (95% CI 82.3%–96.8%), specificity of 96.4% (95% CI 92.7%–98.5%), and accuracy of 95.1% (95% CI 91.7%–97.3%); sensitivity for the subgroup with an SDH thickness above 10 mm was 100%. The maximum thickness mean absolute error was 2.75 mm (95% CI 2.14–3.37 mm), whereas the MLS mean absolute error was 0.93 mm (95% CI 0.55–1.31 mm). The Pearson correlation coefficient computed to determine agreement between automated and manual segmentation measurements was 0.97 (95% CI 0.96–0.98). CONCLUSIONS The described Viz.ai SDH CNN performed exceptionally well at identifying and quantifying key features of SDHs in an independent validation imaging data set.

Implantable bioelectronic devices for the simulation of peripheral nerves could be used to treat disorders that are resistant to traditional pharmacological therapies. However, for many nerve targets, this requires invasive surgeries and the implantation of bulky devices (about a few centimetres in at least one dimension). Here we report the design and in vivo proof-of-concept testing of an endovascular wireless and battery-free millimetric implant for the stimulation of specific peripheral nerves that are difficult to reach via traditional surgeries. The device can be delivered through a percutaneous catheter and leverages magnetoelectric materials to receive data and power through tissue via a digitally programmable 1 mm × 0.8 mm system-on-a-chip. Implantation of the device directly on top of the sciatic nerve in rats and near a femoral artery in pigs (with a stimulation lead introduced into a blood vessel through a catheter) allowed for wireless stimulation of the animals' sciatic and femoral nerves. Minimally invasive magnetoelectric implants may allow for the stimulation of nerves without the need for open surgery or the implantation of battery-powered pulse generators.

Background Different studies have recognized the existence of subtypes of obesity and normal weight, in which it is reported that not all patients show the same cardiometabolic risk, called “metabolically healthy” and “metabolically unhealthy”. In several reviews, differences in the inflammatory profile have been studied, but there is not information on the relationship of body size phenotypes with thrombosis risk. Objective Determine the association between body size phenotypes and fibrinolytic activity by measuring the concentration of plasminogen activator inhibitor-1 (PAI-1). Methods A cross-sectional study was conducted in women aged 40 to 65 years. Anthropometric measurements and biochemical determinations were performed on all participants. The fibrinolytic activity was determined by measuring PAI-1 by ELISA. Karelis criteria were used to define metabolic status. Four groups were formed: Metabolically healthy normal weight (MHNW), Metabolically unhealthy normal weight (MUNW), Metabolically healthy obese (MHO) and Metabolically unhealthy obese (MUO). Results 230 women were included in our study with a mean age 52.3 ± 5.9 years. The concentration of PAI-1 showed a significant difference between the groups MHNW, MUNW, MHO, MUO [2.3 (0.08, 13.6), 12.7, (0.08, 33.1), 23.4 (2.6, 28.8) and 22.8 (2.0, 46.7) ng/mL, respectively, p = 0.006]. Multiple regression analysis identified that BMI and HOMA-IR were independent factors influencing PAI-1 levels. Conclusion This study is the first one that recognizes differences in the fibrinolytic activity between body size phenotypes. The groups with the lowest fibrinolytic activity were MUO and MHO, however, MUNW also present alterations of fibrinolysis, thus suggesting a prothrombotic state.

The plasminogen activator inhibitor type 1 (PAI-1) is the major determinant of fibrinolytic activity. PAI-1 concentrations are elevated in obesity, type 2 diabetes and metabolic syndrome (MetS). On the other hand, during menopause, fibrinolytic activity decreases and, consequently, PAI-1 concentration increases; however, it is debated whether menopause is an independent determinant factor of PAI-1 levels. The objective of this study was to evaluate the effect of hormonal and metabolic status on the concentration of PAI-1 in pre-and post-menopausal women. A case-control study was conducted in ninety pre-and post-menopausal women aged 45 to 55 years, matched by body mass index (BMI). Anthropometric measurements and biochemical determinations were performed on all participants. The fibrinolytic activity was determined by measuring PAI-1 by ELISA. Of all the women, 30% presented MetS. Women with MetS had higher values of PAI-1 (36.0 ± 19.1 vs 19.3 ± 14.8 ng/mL

Objetivo: La cirugía bariátrica es un procedimiento para disminuir de peso a largo plazo en pacientes con obesidad. El objetivo de este estudio fue evaluar los niveles de ghrelina y la reducción del peso de acuerdo al tipo de cirugía bariátrica, comparando el bypass de una sola anastomosis y la gastrectomía formadora de manga. Materiales y Métodos: Estudio de cohorte que incluyó a 50 pacientes con obesidad, 22 mini-bypass y 28 mangas gástricas. Se evaluó el peso corporal y las concentraciones de ghrelina en la etapa prequirúrgica, en el día 7 y en los meses 1, 3 y 6 después de la cirugía. Resultados: Del total de pacientes, el 86% presentaron > 50% pérdida del exceso de peso (PEPP) a los 6 meses. La concentración de ghrelina disminuyó desde la primera semana en el grupo total de participantes. A los 6 meses, se observó mayor reducción de ghrelina en los pacientes con la manga gástrica (4.636 ± 2.535 vs 1.340 ± 1.001 pg/ mL, p < 0,0001). El PEPP en pacientes con mini-bypass fue superior, en comparación con manga gástrica. Conclusiones: La comparación entre las técnicas indicó que, a los 6 meses de evolución posquirúrgica, los pacientes con mini-bypass presentaron mayor reducción de peso corporal y del nivel de ghrelina, en comparación con el grupo de manga gástrica. La concentración de ghrelina es una variable que participa en el control de peso; sin embargo, el tipo de abordaje quirúrgico probablemente tiene mayor relación con la pérdida de peso en estos pacientes.

Excess adipose tissue is considered one of the main causes of metabolic and cardiovascular diseases. Initially, the adipose tissue was considered the main lipid and energy storage of the organism. Subsequently it was discovered that adipose tissue had other functions such as endocrine, controlling different metabolic and immune processes. Currently, different types of adipose tissue are recognized. The white adipocyte represents the main energy reserve, on the contrary the brown adipocyte is responsible for the oxidation of lipids for thermogenesis. The beige adipocyte originates from the white adipocyte, by a process known as "browning", which leads to lipolysis and thermogenesis. The 3 previous types have recently joined the blue adipocyte, which has a role in liver retinoid homeostasis and the pink adipocyte that participates in lactogenesis and is present in the mammary gland of animals; its role is still unknown in humans. The newly identified hormone Irisin is secreted by the skeletal muscle and promotes browning of white to beige adipose tissue, thus favoring thermogenesis. Another interesting aspect of this hormone is that it represents a connection between muscle activity and lipolysis. The above suggests that Irisin may be the key in the prevention and treatment of obesity.