Spark-Discharge-Activated 3D-Printed Electrochemical Sensors.

3D printing technology is a tremendously powerful technology to fabricate electrochemical sensing devices. However, current conductive filaments are not aimed at electrochemical applications and therefore require intense activation protocols to unleash a suitable electrochemical performance. Current activation methods based on (electro)chemical activation (using strong alkaline solutions and organic solvents and/or electrochemical treatments) or combined approaches are time-consuming and require hazardous chemicals and dedicated operator intervention. Here, pioneering spark-discharge-activated 3D-printed electrodes were developed and characterized, and it was demonstrated that their electrochemical performance was greatly improved by the effective removal of the thermoplastic support polylactic acid (PLA) as well as the formation of sponge-like and low-dimensional carbon nanostructures. This reagent-free approach consists of a direct, fast, and automatized spark discharge between the 3D-electrode and the respective graphite pencil electrode tip using a high-voltage power supply. Activated electrodes were challenged toward the simultaneous voltammetric determination of dopamine (DP) and serotonin (5-HT) in cell culture media. Spark discharge has been demonstrated as a promising approach for conductive filament activation as it is a fast, green (0.94 GREEnness Metric Approach), and automatized procedure that can be integrated into the 3D printing pipeline.

Zero-contrast left atrial appendage closure, a feasible alternative for patients with a high risk of contrast-induced nephropathy: Systematic literature review and meta-analysis.

BACKGROUND: Left atrial appendage closure (LAAC) is an alternative to reduce thrombotic risk in patients with nonvalvular atrial fibrillation. This procedure conventionally requires the use of a contrast agent. A significant proportion of patients who undergo this procedure have chronic kidney disease, with a high risk of contrast-induced nephropathy. OBJECTIVE: We aimed to systematically review existing literature regarding the feasibility and safety of a zero-contrast LAAC technique. METHODS: We searched the MEDLINE/PubMed, Embase, and Cochrane Central Register of Controlled Trials databases for studies comparing a zero-contrast LAAC technique with conventional LAAC up to April 2024. From each study, we extracted baseline characteristics, feasibility, and safety outcomes. A random model meta-analysis was used to compare outcomes between groups. RESULTS: Five studies reporting data from 367 patients were included. A 100% successful implantation rate was reported in all the zero-contrast groups. The mean number of recaptures reached no significant difference between the groups (mean difference, -0.15; CI, -0.67 to 0.37; I2 = 0%; P = .58). The zero-contrast group had a significantly shorter fluoroscopy time (mean difference, -4.03; CI, -7.72 to -0.34; I2 = 67%; P = .03). Complications related to the procedure, peridevice leak, and device-associated thrombus rates were not significantly different between the groups. CONCLUSION: Zero-contrast LAAC is a feasible alternative. The success and complication rates are consistent with those of conventional LAAC. Aside from the inherent benefit of zero-contrast exposure, this technique allows a reduction in fluoroscopy time.

General Versus Nongeneral Anesthesia for Middle Meningeal Artery Embolization for Chronic Subdural Hematomas: Multicenter Propensity Score Matched Study.

BACKGROUND AND OBJECTIVES: The choice of anesthesia type (general anesthesia [GA] vs nongeneral anesthesia [non-GA]) in middle meningeal artery embolization (MMAE) procedures for chronic subdural hematomas (cSDH) differs between institutions and left to care team discretion given lack of standard guidelines. We compare the outcomes of GA vs non-GA in MMAE. METHODS: Consecutive patients receiving MMAE for cSDH at 14 North American centers (2018-2023) were included. Clinical, cSDH characteristics, and technical/clinical outcomes were compared between the GA/non-GA groups. Using propensity score matching (PSM), patients were matched controlling for age, baseline modified Rankin Scale, concurrent/prior surgery, hematoma thickness/midline shift, and baseline antiplatelet/anticoagulation. The primary end points included surgical rescue and radiographic success rates (≥50% reduction in maximum hematoma thickness with minimum 2 weeks of imaging). Secondary end points included technical feasibility, procedural complications, and functional outcomes. RESULTS: Seven hundred seventy-eight patients (median age 73 years, 73.2% male patients) underwent 956 MMAE procedures, 667 (70.4%) were non-GA and 280 were GA (29.6%). After running 1:3 PSM algorithm, this resulted in 153 and 296 in the GA and non-GA groups, respectively. There were no baseline/procedural differences between the groups except radial access more significantly used in the non-GA group (P = .001). There was no difference between the groups in procedural technical feasibility, complications rate, length of stay, surgical rescue rates, or favorable functional outcome at the last follow-up. Subsequent 1:1 sensitivity PSM retained the same results. Bilateral MMAE procedures were more performed under non-GA group (75.8% vs 67.2%; P = .01); no differences were noted in clinical/radiographic outcomes between bilateral vs unilateral MMAE, except for longer procedure duration in the bilateral group (median 73 minutes [IQR 48.3-100] vs 54 minutes [39-75]; P < .0001). Another PSM analysis comparing GA vs non-GA in patients undergoing stand-alone MMAE retained similar associations. CONCLUSION: We found no significant differences in radiological improvement/clinical outcomes between GA and non-GA for MMAE.

DNMT3A/TET2/ASXL1 Mutations are an Age-independent Thrombotic Risk Factor in Polycythemia Vera Patients: An Observational Study.

BACKGROUND: Polycythemia vera (PV) patients are classified as high or low thrombotic risk based on age and prior history of thrombosis. Despite adherence to treatment recommendations, vascular events remain frequent, leading us to question whether thrombotic risk stratification could be improved. We previously reported an association between thrombotic events and mutations in DTA genes (DNMT3A, TET2, and ASXL1). The objective of this study was to confirm this observation in a larger series of PV patients. METHODS: PV patients with a minimum follow-up of 3 years were recruited from 8 European centers. Medical history was searched for thrombotic event recorded at any time and next-generation sequencing carried out with a myeloid panel. Multivariable logistic regression evaluated the impact of variables on thrombotic risk. Kaplan-Meier thrombosis-free survival curves were compared by the log rank test. Associations in the total cohort were confirmed in a case-control study to exclude selection bias. RESULTS: Of the 136 patients recruited, 74 (56.1%) had a thrombotic event, with an incidence density of 2.83/100 person-years. In multivariable analysis, DTA mutation was a risk factor for thrombotic event, being predictive for shorter thrombosis-free survival in the whole cohort (p = 0.007), as well as in low-risk patients (p = 0.039) and older patients (p = 0.009), but not for patients with a prediagnostic event. A gender- and age-matched case-control study confirmed the increased risk of thrombotic event for PV patients with a DTA mutation. CONCLUSION: Our results support the use of molecular testing at diagnosis to help predict which PV patients are at higher risk of developing thrombosis.

Print-Pause-Print Fabrication of Tailored Electrochemical Microfluidic Devices.

Three-dimensional (3D) printing technology has emerged as a powerful technology for the fabrication of low-cost microfluidics. Nevertheless, the fabrication of microfluidic devices integrating high-performance electrochemical sensors in practical applications is still an open challenge. Although automatic fabrication of the microfluidic device and the electrodes can be successfully carried out using a one-step multimaterial fused filament fabrication (FFF) approach, the as-printed electrochemical performance of these electrodes is not good enough for chemical (bio)sensing and their surface modification is challenging because after closing the channel there is no physical access to the electrode. Thus, here a pause-print-pause (PPP) microfabrication approach was implemented. The fabrication was paused before printing the microfluidics, and the filament-based electrodes were directly modified on the printing bed via stencil printing, drop casting, and electrodeposition. To exemplify this versatile workflow, the design of a microfluidic glucose sensor was proposed. To this end, first, the working and counter electrodes were stencil printed with graphite ink while the reference electrode was stencil printed with Ag|AgCl ink. Then, Prussian blue was formed on the working electrode either by drop casting or by electrodeposition, and glucose oxidase was drop cast on top. At this point, the microfabrication process was resumed, and the microfluidics were printed on top of the modified electrodes to complete the construction of hybrid electrochemical fluidic fused filament fabricated devices (h-eF4Ds). This print-pause-print approach is not limited to ink-based electrodes or glucose oxidase, and we envisage these results will pave the way for the effective integration of electrodes in microfluidic devices in a simple and clean-room-free approach, allowing the development of highly customized eF4Ds for a plethora of analytes with high significance.

Successful Percutaneous Coronary Intervention in Chronic Total Occlusion after Coronary Perforation.

Coronary chronic total occlusions are challenging lesions with high rates of complications related to percutaneous intervention. We describe a successful angioplasty in a patient with a recent coronary perforation, using multiple techniques, such as stick and swap with Stingray, subintimal transcatheter withdrawal, and investment.

Predicting posttraumatic epilepsy using admission electroencephalography after severe traumatic brain injury.

OBJECTIVE: Posttraumatic epilepsy (PTE) develops in as many as one third of severe traumatic brain injury (TBI) patients, often years after injury. Analysis of early electroencephalographic (EEG) features, by both standardized visual interpretation (viEEG) and quantitative EEG (qEEG) analysis, may aid early identification of patients at high risk for PTE. METHODS: We performed a case-control study using a prospective database of severe TBI patients treated at a single center from 2011 to 2018. We identified patients who survived 2 years postinjury and matched patients with PTE to those without using age and admission Glasgow Coma Scale score. A neuropsychologist recorded outcomes at 1 year using the Expanded Glasgow Outcomes Scale (GOSE). All patients underwent continuous EEG for 3-5 days. A board-certified epileptologist, blinded to outcomes, described viEEG features using standardized descriptions. We extracted 14 qEEG features from an early 5-min epoch, described them using qualitative statistics, then developed two multivariable models to predict long-term risk of PTE (random forest and logistic regression). RESULTS: We identified 27 patients with and 35 without PTE. GOSE scores were similar at 1 year (p = .93). The median time to onset of PTE was 7.2 months posttrauma (interquartile range = 2.2-22.2 months). None of the viEEG features was different between the groups. On qEEG, the PTE cohort had higher spectral power in the delta frequencies, more power variance in the delta and theta frequencies, and higher peak envelope (all p < .01). Using random forest, combining qEEG and clinical features produced an area under the curve of .76. Using logistic regression, increases in the delta:theta power ratio (odds ratio [OR] = 1.3, p < .01) and peak envelope (OR = 1.1, p < .01) predicted risk for PTE. SIGNIFICANCE: In a cohort of severe TBI patients, acute phase EEG features may predict PTE. Predictive models, as applied to this study, may help identify patients at high risk for PTE, assist early clinical management, and guide patient selection for clinical trials.

Digital manufacturing for accelerating organ-on-a-chip dissemination and electrochemical biosensing integration.

Organ on-a-chip (OoC) is a promising technology that aims to recapitulate human body pathophysiology in a more precise way to advance in drug development and complex disease understanding. However, the presence of OoC in biological laboratories is still limited and mainly restricted to laboratories with access to cleanroom facilities. Besides, the current analytical methods employed to extract information from the organ models are endpoint and post facto assays which makes it difficult to ensure that during the biological experiment the cell microenvironment, cellular functionality and behaviour are controlled. Hence, the integration of real-time biosensors is highly needed and requested by the OoC end-user community to provide insight into organ function and responses to stimuli. In this context, electrochemical sensors stand out due to their advantageous features like miniaturization capabilities, ease of use, automatization and high sensitivity and selectivity. Electrochemical sensors have been already successfully miniaturized and employed in other fields such as wearables and point-of-care devices. We have identified that the explanation for this issue may be, to a large extent, the accessibility to microfabrication technologies. These fields employ preferably digital manufacturing (DM), which is a more accessible microfabrication approach regardless of funding and facilities. Therefore, we envision that a paradigm shift in microfabrication that adopts DM instead of the dominating soft lithography for the in-lab microfabrication of OoC devices will contribute to the dissemination of the field and integration of the promising real-time sensing.

Secondary Acrocyanosis in a Paraplegic Patient With Spinal Cord Injury.

Secondary acrocyanosis after spinal cord injury is extremely rare. We describe a case with secondary acrocyanosis in a complete T12 paraplegic patient. A 41-year-old man with complete T12 paraplegia after a gunshot wound to the thoracic spine 20 years prior presented with a four-month history of bilateral foot bluish discoloration precipitated when he sat with his legs down, improving rapidly after a few minutes of leg elevation. Changes in the skin color of the lower extremities were evaluated in the seated position for two hours. The skin color became darker, progressing to a bluish discoloration through the entire length of the legs. After two hours, the feet and most of the legs appeared deep purple. The color of the legs returned to their baseline three minutes later after the patient was placed supine in the bed. The diagnosis of secondary acrocyanosis due to the T12 spinal cord injury was established based on the physical examination and ancillary tests showing no peripheral ischemia. Other causes of secondary acrocyanosis were excluded during the work-up. This report presents the first case of a paraplegic patient with spinal cord injury presenting secondary acrocyanosis.

New trends in enzyme-free electrochemical sensing of ROS/RNS. Application to live cell analysis.

The ubiquity and importance of ROS and RNS in cellular signaling, disease development, and death give rise to an outstanding interest in their detection and quantification. Among the analytical techniques available, electrochemical sensors stand out for the detection of ROS/RNS due to their high sensitivity and inherent miniaturization which allows the in situ and real-time detection together with a tunable selectivity due to the different electrochemical behavior of ROS/RNS. Nanomaterial-based enzyme-free electrochemical sensors possess improved sensitivity, selectivity, stability, and unique catalytic activities. In addition, their integration in nanoelectrodes, lab-on-chips, microfluidic systems, and stretchable electrodes allow the determination of ROS/RNS in individual cells, cell organelles, or cell populations, under different experimental conditions hardly accessible using classical detection methods.

TMS intensity and focality correlation with coil orientation at three non-motor regions.

Objective. The aim of this study is to define the best coil orientations for transcranial magnetic stimulation (TMS) for three clinically relevant brain areas: pre-supplementary motor area (pre-SMA), inferior frontal gyrus (IFG), and posterior parietal cortex (PPC), by means of simulations in 12 realistic head models of the electric field (E-field).Methods. We computed the E-field generated by TMS in our three volumes of interest (VOI) that were delineated based on published atlases. We then analysed the maximum intensity and spatial focality for the normal and absolute components of the E-field considering different percentile thresholds. Lastly, we correlated these results with the different anatomical properties of our VOIs.Results. Overall, the spatial focality of the E-field for the three VOIs varied depending on the orientation of the coil. Further analysis showed that differences in individual brain anatomy were related to the amount of focality achieved. In general, a larger percentage of sulcus resulted in better spatial focality. Additionally, a higher normal E-field intensity was achieved when the coil axis was placed perpendicular to the predominant orientations of the gyri of each VOI. A positive correlation between spatial focality and E-field intensity was found for PPC and IFG but not for pre-SMA.Conclusions. For a rough approximation, better coil orientations can be based on the individual's specific brain morphology at the VOI. Moreover, TMS computational models should be employed to obtain better coil orientations in non-motor regions of interest.Significance. Finding better coil orientations in non-motor regions is a challenge in TMS and seeks to reduce interindividual variability. Our individualized TMS simulation pipeline leads to fewer inter-individual variability in the focality, likely enhancing the efficacy of the stimulation and reducing the risk of stimulating adjacent, non-targeted areas.

The right ventricle of transplanted hearts at 2,640 meters above sea level. A latin-american experience. / El ventrículo derecho de los corazones trasplantados a 2,640 metros sobre el nivel del mar. Una experiencia latinoamericana

BACKGROUND: High-altitude cardiovascular adaptations increase lung pressure. This effect on the right ventricle (RV) of transplanted hearts at altitudes above 2,500 meters above sea level (masl) has not been described. OBJECTIVE: The objective of the study was to describe echocardiography RV behavior in the immediate post-operative period (Days 1-7 post-Heart transplant [HTx]), 3, 6, 12, and 24 months after HTx in patients at 2640 masl. METHODS: Historical cohort of HTx patients in the period between 2005 and 2019, in a hospital located in Bogotá, Colombia. Socio-demographic, clinical, and echocardiographic evaluation data of the RV at 5 follow-up moments were analyzed. RESULTS: 91 patients underwent HTx, 64% remained at a height > 2500 masl in the post-operative period. Transthoracic echo was available in 37 patients (40.6%). Right ventricular dysfunction was found in 95% of patients, which was predominantly moderate (43%), with improvement 3 months after transplant. The immediate post-operative Tricuspid annular plane systolic excursion was 8.9 ± 4.9 mm, with recovery from the 3rd post-operative month (15.1 ± 3.6 mm) and without significant changes in month 24 (15.8 ± 4.9 mm). Immediate post-operative systolic pulmonary artery pressure (sPAP) was 39.2 ± 8.2 mmHg, showing a decrease at 24 post-operative months (31.0 ± 5.0 mmHg). The 5-year survival was 78% Confidence Interval 95% 60-85. CONCLUSION: After HTx, most patients present right ventricular dysfunction, improving at the 3rd month of transplant. There were no significant differences between patients living at more than 2500 masl and < 2500 masl.

ANTECEDENTES: Las adaptaciones cardiovasculares en la altitud aumentan la presión pulmonar; el efecto de estos cambios sobre el ventrículo derecho de corazones trasplantados a altitudes superiores a 2,500 msnm no ha sido descrito. OBJETIVO: Describir el comportamiento por ecocardiografía transtorácica del ventrículo derecho en el postoperatorio inmediato (días 1­7 post-HTx), 3, 6, 12 y 24 meses después del trasplante cardíaco en pacientes intervenidos a 2,640 ms nm. MÉTODOS: Cohorte histórica de pacientes trasplantados de corazón en un hospital de Bogotá, Colombia, entre 2005 y 2019. Los datos sociodemográficos, clínicos y ecocardiográficos del ventrículo derecho fueron analizados en 5 momentos del seguimiento postoperatorio. RESULTADOS: 91 pacientes fueron sometidos a trasplante cardíaco, el 64% residía a más de 2,500 msnm en el postoperatorio. El ecocardiograma transtorácico estuvo disponibles en 37 pacientes (40.6%). En el 95% de los pacientes se documentó disfunción del ventrículo derecho la cual fue predominantemente moderada (43%), con mejoría al 3 mes del trasplante. El TAPSE en el postoperatorio inmediato fue de 8.9±4.9 mm, con recuperación a partir del tercer mes postoperatorio (15.1±3.6 mm); la mejoría se mantuvo hasta el mes 24 (15.8±4.9 mm). La PsAP postoperatoria inmediata fue de 39.2±8.2 mmHg y disminuyó a los 24 meses (31.0±5.0 mmHg). La supervivencia a los 5 años fue del 78% IC95% 60-85. CONCLUSIONES: Posterior al trasplante cardíaco, la mayoría de los pacientes presentó disfunción ventricular derecha, mejorando al tercer mes del trasplante. No hubo diferencias significativas entre los pacientes que vivían a mas de 2,500 msnm y menos de 2,500 msnm.

Effect of Foaming Formulation and Operating Pressure on Thermoregulating Polyurethane Foams.

The synthesis of rigid polyurethane (RPU) foams containing thermoregulatory microcapsules has been carried out under reduced pressure conditions with a new foaming formulation to reduce the final composite densities. These optimized RPU foams were able to overpass the drawbacks exhibited by the previous composites over the studied temperature range, working as insulating and thermal energy storage materials. The change in the formulation allowed to decrease the final foam density and enhance their mechanical strength. The effect of the operating pressure (atmospheric, 800 mbar, and 700 mbar) and microcapsules content (up to 30 wt%) on the physical, mechanical, and thermal PU foam properties was studied. The reduction of the pressure from atmospheric to 800 mbar did not have any effect on the cell size, strut thickness, and compression strength 10% of deformation, the Young modulus being even higher at 800 mbar. Nevertheless, a strong impact on the microstructure and mechanical properties was observed for the foam composites obtained at 700 mbar. A deleterious impact on the RPU foams thermal conductivity was observed when using low-pressure conditions. Thermal analyses showed that a composite able to work as heat accumulator and thermal insulation both at transient and at steady state was achieved.

Fibrosis endomiocárdica: una cardiomiopatía restrictiva en países en vía de desarrollo / Endomyocardial fibrosis: a restrictive cardiomyopathy in developing countries

Resumen Objetivo: La fibrosis endomiocárdica (FE) es una cardiomiopatía restrictiva infrecuente. En América Latina son escasos los reportes. En el presente trabajo se realiza una descripción de una serie de pacientes diagnosticados de FE en Colombia. Método: Realizamos una búsqueda en los registros de imágenes de resonancia magnética (RM) cardiaca realizadas en nuestra institución entre 2016 y 2019 en busca de pacientes con diagnóstico de FE. Se describieron sus características sociodemográficas, clínicas y de imagen. Resultados: Nueve pacientes fueron diagnosticados de FE (el 66.7% mujeres), con una edad promedio de 69 años. Los pacientes presentaron un promedio de 2.6 años de evolución. El principal síntoma referido fue disnea, seguido de síncope, dolor torácico y palpitaciones. En ninguno de ellos se sospechó FE como diagnóstico inicial. En cuanto a los hallazgos ecocardiográficos, se identificó compromiso predominante del ventrículo izquierdo, seguido de compromiso biventricular. Todos los pacientes presentaron patrón de llenado restrictivo con dilatación auricular izquierda severa. En el análisis retrospectivo se cumplieron los criterios de Mocumbi para el diagnóstico de FE en el 100% de los pacientes con gravedad moderada (77.8%). Las imágenes de RM mostraron función sistólica biventricular y volúmenes preservados. Se observó depósito focal de gadolinio subendocárdico a nivel apical y se confirmó la presencia de trombo en el 66% de los casos Conclusión:: La FE es una cardiomiopatía restrictiva infrecuente circunscrita a países tropicales. La mayoría de los pacientes en nuestra serie presentaron compromiso aislado del ventrículo izquierdo, seguido de compromiso biventricular, con función ventricular usualmente preservada.

Abstract Objective: Endomyocardial fibrosis (EF) is an unusual restrictive cardiomyopathy. In Latin America there are few reports. Here, we made a description of patients diagnosed with EF in Colombia. Method: We conducted a search in the records of cardiac magnetic resonance imaging (MRI) performed in our institution between 2016-2019 looking for patients with a diagnosis of EF; sociodemographic, clinical and imaging characteristics were described. Results: Nine patients were diagnosed with EF (66.7% female), with an average age of 69 years. Patients presented an average evolution of 2.6 years. The main reported symptom was dyspnea, followed by syncope, chest pain, and palpitations. None of them was initially suspected for EF. Regarding echocardiographic findings, predominant left ventricular involvement was identified, followed by bi-ventricular involvement. All the patients presented a restrictive filling pattern with severe left atrial dilation. In a retrospective analysis, Mocumbi criteria for diagnosis of EF were met in 100% of the patients, majority with moderate severity (77.8%). Cardiac MRI showed biventricular systolic function and volumes preserved. Focal subendocardial late gadolinium enhancement was observed on the apex and apical thrombus was confirmed in 66% of the patients Conclusion: FE is an uncommon restrictive cardiomyopathy limited to tropical countries. Most of patients in our series presented isolated involvement of left ventricle, followed by bi-ventricular involvement, with ventricular function usually preserved.

Diffusion of Shape Stabilized PEG-SiO2 as a Driver for Producing Thermoregulating Facing Bricks.

A novel form-stable phase-change material (PCM) based on facing bricks was developed by incorporating thermoregulating PEG-SiO2, synthetized by sol-gel method and based on polyethylene glycol as phase-change material and silica as stabilizer compound. The PEG-SiO2 in its liquid form (sol) is firstly adsorbed inside the porous brick and lastly stabilized (gel) by controlling its gelation time, obtaining form-stable PCMs with PEG-SiO2 contents within 15-110 wt.%. Kinetic adsorption curves of the sol into bricks having different porosities as well as maximum adsorption capacities were obtained. The effective diffusion coefficients (Deff) were estimated by means of Fick's second law, it being possible to predict the adsorption of sol PEG-SiO2 by the brick as function of its porosity and the free diffusion coefficient. Finally, form-stable PCMs demonstrated an improvement in their thermal energy storage capacity (up to 338%), these materials being capable of buffering the indoor temperature during an entire operational day.

Endomyocardial fibrosis: a restrictive cardiomyopathy in developing countries.

OBJECTIVE: Endomyocardial fibrosis (EF) is an unusual restrictive cardiomyopathy. In Latin America there are few reports. Here, we made a description of patients diagnosed with EF in Colombia. METHOD: We conducted a search in the records of cardiac magnetic resonance imaging (MRI) performed in our institution between 2016-2019 looking for patients with a diagnosis of EF; sociodemographic, clinical and imaging characteristics were described. RESULTS: Nine patients were diagnosed with EF (66.7% female), with an average age of 69 years. Patients presented an average evolution of 2.6 years. The main reported symptom was dyspnea, followed by syncope, chest pain, and palpitations. None of them was initially suspected for EF. Regarding echocardiographic findings, predominant left ventricular involvement was identified, followed by bi-ventricular involvement. All the patients presented a restrictive filling pattern with severe left atrial dilation. In a retrospective analysis, Mocumbi criteria for diagnosis of EF were met in 100% of the patients, majority with moderate severity (77.8%). Cardiac MRI showed biventricular systolic function and volumes preserved. Focal subendocardial late gadolinium enhancement was observed on the apex and apical thrombus was confirmed in 66% of the patients. CONCLUSION: FE is an uncommon restrictive cardiomyopathy limited to tropical countries. Most of patients in our series presented isolated involvement of left ventricle, followed by bi-ventricular involvement, with ventricular function usually preserved.

OBJETIVO: La fibrosis endomiocárdica (FE) es una cardiomiopatía restrictiva infrecuente. En América Latina son escasos los reportes. En el presente trabajo se realiza una descripción de una serie de pacientes diagnosticados de FE en Colombia. MÉTODO: Realizamos una búsqueda en los registros de imágenes de resonancia magnética (RM) cardiaca realizadas en nuestra institución entre 2016 y 2019 en busca de pacientes con diagnóstico de FE. Se describieron sus características sociodemográficas, clínicas y de imagen. RESULTADOS: Nueve pacientes fueron diagnosticados de FE (el 66.7% mujeres), con una edad promedio de 69 años. Los pacientes presentaron un promedio de 2.6 años de evolución. El principal síntoma referido fue disnea, seguido de síncope, dolor torácico y palpitaciones. En ninguno de ellos se sospechó FE como diagnóstico inicial. En cuanto a los hallazgos ecocardiográficos, se identificó compromiso predominante del ventrículo izquierdo, seguido de compromiso biventricular. Todos los pacientes presentaron patrón de llenado restrictivo con dilatación auricular izquierda severa. En el análisis retrospectivo se cumplieron los criterios de Mocumbi para el diagnóstico de FE en el 100% de los pacientes con gravedad moderada (77.8%). Las imágenes de RM mostraron función sistólica biventricular y volúmenes preservados. Se observó depósito focal de gadolinio subendocárdico a nivel apical y se confirmó la presencia de trombo en el 66% de los casos. CONCLUSIÓN: La FE es una cardiomiopatía restrictiva infrecuente circunscrita a países tropicales. La mayoría de los pacientes en nuestra serie presentaron compromiso aislado del ventrículo izquierdo, seguido de compromiso biventricular, con función ventricular usualmente preservada.

Improving the Hydrophilicity of Flexible Polyurethane Foams with Sodium Acrylate Polymer.

Hydrophilic, flexible polyurethane (FPU) foams made from Hypol prepolymers are capable of retaining large amounts of water and saline solutions. The addition of different catalysts and surfactant agents to Hypol JM 5008 prepolymer was assayed to obtain a foam with good structural stability and elasticity. The combination of three catalysts, stannous octoate and two amine-based ones (Tegoamin 33 and Tegoamin BDE), and the surfactant Niax silicone L-620LV allowed to synthesize a foam with a homogeneous cell size distribution, exhibiting the highest saline absorption capacity (2.4 g/gram of foam) and almost complete shape recovery, with up to a 20% of remaining deformation. Then, superabsorbent sodium acrylate polymer (PNaA) was added to the FPU foam up to 8 pph. The urine absorption capacity of the foam was increased about 24.8% by incorporating 6 pph of PNaA, absorbing 17.46 g of saline solution per foam gram, without any negative impact on the rest of the foam properties. All these properties make the synthesized foams suitable for corporal fluids absorption applications in which elasticity and low-density are required.