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1.
J Am Chem Soc ; 146(22): 15648-15658, 2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38767460

RESUMEN

The sunlight-driven reduction of CO2 into fuels and platform chemicals is a promising approach to enable a circular economy. However, established optimization approaches are poorly suited to multivariable multimetric photocatalytic systems because they aim to optimize one performance metric while sacrificing the others and thereby limit overall system performance. Herein, we address this multimetric challenge by defining a metric for holistic system performance that takes multiple figures of merit into account, and employ a machine learning algorithm to efficiently guide our experiments through the large parameter matrix to make holistic optimization accessible for human experimentalists. As a test platform, we employ a five-component system that self-assembles into photocatalytic micelles for CO2-to-CO reduction, which we experimentally optimized to simultaneously improve yield, quantum yield, turnover number, and frequency while maintaining high selectivity. Leveraging the data set with machine learning algorithms allows quantification of each parameter's effect on overall system performance. The buffer concentration is unexpectedly revealed as the dominating parameter for optimal photocatalytic activity, and is nearly four times more important than the catalyst concentration. The expanded use and standardization of this methodology to define and optimize holistic performance will accelerate progress in different areas of catalysis by providing unprecedented insights into performance bottlenecks, enhancing comparability, and taking results beyond comparison of subjective figures of merit.

2.
Phys Rev Lett ; 132(2): 028201, 2024 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-38277585

RESUMEN

We show here that soap films-typically expected to host symmetric molecular arrangements-can be constructed with differing opposite surfaces, breaking their symmetry, and making them reminiscent of functional biological motifs found in nature. Using fluorescent molecular probes as dopants on different sides of the film, resonance energy transfer could be employed to confirm the lack of symmetry, which was found to persist on timescales of several minutes. Further, a theoretical analysis of the main transport phenomena involved yielded good agreement with the experimental observations.

3.
Indian Pacing Electrophysiol J ; 22(3): 161-164, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35378279

RESUMEN

Subcutaneous hematoma is a complication of cardiac device implantation. In most cases, it is drained or spontaneously reabsorbed. While cases of chylothorax are rare, and cases of pseudochylothorax even rarer, previous cases of accumulation of chyliform material in the subcutaneous pockets of cardiac devices are anecdotal. We present a case of a 60-year-old man with antiphospholipids antibody syndrome and rheumatoid arthritis, who underwent dual-chamber ICD implantation in December 2020; the procedure was complicated by a pocket hematoma, which required surgical drainage. After 7 months, the man returned owing to heart failure, with evidence of the reappearance of a large swelling in the ICD pocket; this was tolerated for months by the patient and was no longer controlled. We drained 100ml of gold-colored, odorless liquid, and found no evidence of blood material in the pocket. The liquid was not pus, as culture testing proved negative for bacterial growth. Chemical-physical examination revealed elevated cholesterol concentration (704 mg/dl) and low levels of triglycerides (80 mg/dl; plasma cholesterol values were 91mg/dl, and triglycerides 48 mg/dl). Microscopic examination revealed isolated leukocytes and rare erythrocytes immersed in mucoid material; cytological analysis showed a carpet of macrophages filled with cholesterol. This evidence supports the diagnosis of pseudochyle fluid, formed by the degradation of a hematoma left intact in a closed cavity for more than 6 months. This is an extremely rare case of chyliform fluid documented in an ICD pocket.

4.
J Am Chem Soc ; 143(37): 15103-15112, 2021 09 22.
Artículo en Inglés | MEDLINE | ID: mdl-34498857

RESUMEN

We study the properties of the interface of water and the surfactant hexaethylene glycol monododecyl ether (C12E6) with a combination of heterodyne-detected vibrational sum frequency generation (HD-VSFG), Kelvin-probe measurements, and molecular dynamics (MD) simulations. We observe that the addition of the hydrogen-bonding surfactant C12E6, close to the critical micelle concentration (CMC), induces a drastic enhancement in the hydrogen bond strength of the water molecules close to the interface, as well as a flip in their net orientation. The mutual orientation of the water and C12E6 molecules leads to the emergence of a broad (∼3 nm) interface with a large electric field of ∼1 V/nm, as evidenced by the Kelvin-probe measurements and MD simulations. Our findings may open the door for the design of novel electric-field-tuned catalytic and light-harvesting systems anchored at the water-surfactant-air interface.

5.
Phys Chem Chem Phys ; 23(31): 16948-16957, 2021 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-34338258

RESUMEN

The anomalous behavior of confined water at the nanoscale has remarkable implications in a number of nanotechnological applications. In this work, we analyze the effect of water self-diffusion on the dynamic properties of a solvated gadolinium-based paramagnetic complex, typically used for contrast enhancement in magnetic resonance imaging. In particular, we examine the effect of silica-based nanostructures on water behavior in the proximity of the paramagnetic complex via atomistic simulations, and interpret the resulting tumbling dynamics in the light of the local solvent modification based on the Lipari-Szabo formalism and of the fractional Stokes-Einstein relation. It is found that the local water confinement induces an increased "stiffness" on the outer sphere of the paramagnetic complex, which eventually reduces its tumbling properties. These model predictions are found to explain well the relaxivity enhancement observed experimentally by confining paramagnetic complexes into porous nanoconstructs, and thus offer mechanistic guidelines to design improved contrast agents for imaging applications.

6.
Monaldi Arch Chest Dis ; 92(2)2021 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-34802223

RESUMEN

Giant coronary artery aneurysm is an uncommon disease, treated with surgical intervention or percutaneous coil embolization. A thrombosed aneurysm can cause extrinsic compression on the cardiac chambers, with potential hemodynamic effects and may cause problems when we need to implant a cardiac device. We present a case of difficult pacemaker implantation in a patient with 3 syncopes, first-degree AV block and complete left bundle branch block on electrocardiogram. The patient presented a giant aneurysm of the right coronary artery (85 x 90 mm), thrombosed, with right atrial compression. The pacemaker implantation was hampered by the difficulty of passing the lead through the compressed right atrium; indeed, only with simultaneous echocardiographic and fluoroscopic guidance, was it possible to complete the procedure. This case demonstrates the utility of echocardiogram, in particular settings, in cardiac stimulation procedures.


Asunto(s)
Bloqueo Atrioventricular , Aneurisma Coronario , Marcapaso Artificial , Bloqueo Atrioventricular/etiología , Bloqueo de Rama , Aneurisma Coronario/diagnóstico , Aneurisma Coronario/diagnóstico por imagen , Atrios Cardíacos/diagnóstico por imagen , Humanos , Marcapaso Artificial/efectos adversos
7.
Monaldi Arch Chest Dis ; 91(3)2021 Mar 09.
Artículo en Inglés | MEDLINE | ID: mdl-33691391

RESUMEN

Pheochromocytoma is a rare adrenal tumor characterized by the secretion of catecholamines and vasoactive peptides. It can cause a catecholaminergic storm and lead to acute coronary syndromes. We present the case of a 53-year-old man, without any medical history, who arrived to the hospital following a spinal trauma due a fall. He presents back and retrosternal pain, with a clinical status of acute pulmonary edema, sinus tachycardia with left bundle branch block, left ventricular apical ballooning with depressed systolic function. Blood tests show a very important increase of Troponin and transaminases. A contrast chest-abdomen CT highlighted a right adrenal solid mass, with a diameter of 78mm, partial capsular laceration, compression of the inferior vena cava and the hepatic parenchyma. The clinical condition of the patient rapidly worsens from a respiratory and hemodynamic point of view, with cardiogenic shock, anuria and sepsis, refractory to all the medical treatments, until the patient died. The autopsy confirmed that the abdominal mass was a pheochromocytoma, broken after the trauma suffered. The resulting catecholaminergic storm caused a myocardial ischemia with Takotsubo syndrome, with cardiogenic shock. This unfortunate case confirms the pheochromocytoma as important risk factor for the onset of Takotsubo syndrome, and the how dramatic and severe a catecholaminergic storm can be.


Asunto(s)
Neoplasias de las Glándulas Suprarrenales , Feocromocitoma , Cardiomiopatía de Takotsubo , Neoplasias de las Glándulas Suprarrenales/complicaciones , Neoplasias de las Glándulas Suprarrenales/diagnóstico , Arritmias Cardíacas , Catecolaminas , Humanos , Masculino , Persona de Mediana Edad , Feocromocitoma/complicaciones , Cardiomiopatía de Takotsubo/complicaciones , Cardiomiopatía de Takotsubo/diagnóstico
8.
J Electrocardiol ; 58: 37-42, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31710873

RESUMEN

Andersen-Tawil Syndrome (ATS) is a rare periodic paralysis with typical skeletal and neuromuscular features. Cardiac involvement may range from asymptomatic ventricular arrhythmias to sudden death. Its management remains challenging and the choice between antiarrhythmic drug therapy and implantable cardioverter defibrillator (ICD) is not simple. We present a case of ATS patient with episodes of bidirectional ventricular tachycardia, well controlled by flecainide therapy initially, which in particular conditions of fever and hypokaliemia had a cardiac arrest with ventricular fibrillation, with neurological sequelae and need of an ICD implant. A review of the therapeutic management of this disease is presented.


Asunto(s)
Síndrome de Andersen , Desfibriladores Implantables , Taquicardia Ventricular , Síndrome de Andersen/complicaciones , Síndrome de Andersen/diagnóstico , Síndrome de Andersen/terapia , Antiarrítmicos/uso terapéutico , Muerte Súbita Cardíaca/prevención & control , Electrocardiografía , Flecainida , Humanos , Taquicardia Ventricular/tratamiento farmacológico , Taquicardia Ventricular/terapia
9.
Echocardiography ; 36(10): 1936-1940, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31573719

RESUMEN

Stanford type-A aortic dissection is a clinical emergency; mortality is high, and surgery is urgently required in most cases. Chronic forms of type-A dissection are rare and have a poor prognosis if not treated surgically. We present an unusual case of chronic type-A aortic dissection, with silent onset, in an oncologic patient without risk factors, which was managed conservatively and remained substantially stable during follow-up.


Asunto(s)
Aneurisma de la Aorta Torácica/complicaciones , Aneurisma de la Aorta Torácica/terapia , Disección Aórtica/complicaciones , Disección Aórtica/terapia , Tratamiento Conservador/métodos , Neoplasias Pancreáticas/complicaciones , Anciano , Disección Aórtica/diagnóstico por imagen , Aorta/diagnóstico por imagen , Aneurisma de la Aorta Torácica/diagnóstico por imagen , Enfermedad Crónica , Ecocardiografía/métodos , Resultado Fatal , Humanos , Masculino , Tomografía Computarizada por Rayos X/métodos
10.
J Clin Ultrasound ; 46(4): 259-261, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-28656711

RESUMEN

We report a case of left atrial extrinsic compression caused by an esophageal food bolus in a patient presenting with acute heart failure. Transthoracic echocardiography along with contrast-enhanced CT showed evidence of esophageal dilation producing left atrial compression. Esophageal endoscopy and fragmentation of the bolus, allowing the accumulated food to descend into the stomach, produced a rapid improvement of hemodynamic and clinical status. © 2017 Wiley Periodicals, Inc. J Clin Ultrasound 46:259-261, 2018.


Asunto(s)
Ecocardiografía , Esófago/diagnóstico por imagen , Cuerpos Extraños/diagnóstico por imagen , Atrios Cardíacos/diagnóstico por imagen , Insuficiencia Cardíaca/etiología , Tomografía Computarizada por Rayos X , Anciano , Femenino , Alimentos , Cuerpos Extraños/complicaciones , Humanos
11.
Entropy (Basel) ; 20(2)2018 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-33265217

RESUMEN

In this work, we derive different systems of mesoscopic moment equations for the heat-conduction problem and analyze the basic features that they must hold. We discuss two- and three-equation systems, showing that the resulting mesoscopic equation from two-equation systems is of the telegraphist's type and complies with the Cattaneo equation in the Extended Irreversible Thermodynamics Framework. The solution of the proposed systems is analyzed, and it is shown that it accounts for two modes: a slow diffusive mode, and a fast advective mode. This latter additional mode makes them suitable for heat transfer phenomena on fast time-scales, such as high-frequency pulses and heat transfer in small-scale devices. We finally show that, if proper initial conditions are provided, the advective mode disappears, and the solution of the system tends asymptotically to the transient solution of the classical parabolic heat-conduction equation.

12.
Echocardiography ; 32(3): 420-7, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25047126

RESUMEN

BACKGROUND: Atrial fibrillation (AF) is the most common sustained arrhythmia, with a high recurrence rate, especially during the first months after cardioversion (CV). Few parameters have been evaluated as predictors for the maintenance of sinus rhythm (SR), with limited results. Recently total atrial conduction time (TACT) has been proposed as independent predictor of AF recurrence. The aim of this study was to investigate the prognostic value of TACT, measured using PA-TDI duration, to predict 1-year maintenance of restored SR after electrical CV. METHODS AND RESULTS: In a population of 104 patients (58 male, aged 70 ± 9) with persistent AF, submitted to external electrical CV, we performed a complete echocardiogram after restoring SR. The TACT was estimated by measuring the time delay between the onset of the P-wave in lead II of the surface electrocardiogram and the peak A'-wave on the tissue Doppler imaging (TDI) tracing of the left atrial lateral wall (so-called PA-TDI duration). After a mean follow-up of 14 ± 2 months, 34 (33%) patients had recurrent AF, whereas 70 (67%) patients maintained SR. At multivariate analysis only PA-TDI was identified as independent predictor of AF recurrence (HR 1.04; 95% CI 1.03-1.06; P < 0.001). Receiver operator characteristics curve analyses demonstrated a high degree of discrimination (area under the curve 0.923); with a cut point of 152 msec, we obtain a good diagnostic accuracy (sensitivity 91%, specificity 87%). CONCLUSION: The TACT using TDI is an independent predictor of AF recurrence and can be used to predict the maintenance of SR after external electrical CV.


Asunto(s)
Fibrilación Atrial/diagnóstico , Fibrilación Atrial/prevención & control , Ecocardiografía Doppler/métodos , Diagnóstico por Imagen de Elasticidad/métodos , Cardioversión Eléctrica/métodos , Electrocardiografía/métodos , Anciano , Fibrilación Atrial/fisiopatología , Enfermedad Crónica , Femenino , Atrios Cardíacos/diagnóstico por imagen , Atrios Cardíacos/fisiopatología , Humanos , Masculino , Conducción Nerviosa , Pronóstico , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Resultado del Tratamiento
13.
Echocardiography ; 31(7): E215-7, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24702723

RESUMEN

Isolated supravalvular pulmonary stenosis is a rare finding, usually evidenced in the pediatric age. Here, we report a case of a 76-year-old patient with isolated, severely obstructive, pulmonary supravalvular stenosis. The peculiarity of the present case is the paucity of symptoms and lack of changes in right heart sections, despite of the importance of stenosis. The report confirms the utility of transthoracic two- and three-dimensional echocardiography and transesophageal echocardiography in the detection and quantification of this rare anomaly.


Asunto(s)
Ecocardiografía Tridimensional/métodos , Ecocardiografía Transesofágica/métodos , Estenosis de la Válvula Pulmonar/diagnóstico por imagen , Anciano , Diagnóstico Diferencial , Humanos , Masculino , Enfermedades Raras
14.
Discov Nano ; 18(1): 9, 2023 02 09.
Artículo en Inglés | MEDLINE | ID: mdl-36757508

RESUMEN

We focus on a novel concept of photosynthetic soft membranes, possibly able to allow the conversion of solar energy and carbon dioxide (CO[Formula: see text]) into green fuels. The considered membranes rely on self-assembled functional molecules in the form of soap films. We elaborate a multi-scale and multi-physics model to describe the relevant phenomena, investigating the expected performance of a single soft photosynthetic membrane. First, we present a macroscale continuum model, which accounts for the transport of gaseous and ionic species within the soap film, the chemical equilibria and the two involved photocatalytic half reactions of the CO[Formula: see text] reduction and water oxidation at the two gas-surfactant-water interfaces of the soap film. Second, we introduce a mesoscale discrete Monte Carlo model, to deepen the investigation of the structure of the functional monolayers. Finally, the morphological information obtained at the mesoscale is integrated into the continuum model in a multi-scale framework. The developed tools are then used to perform sensitivity studies in a wide range of possible experimental conditions, to provide scenarios on fuel production by such a novel approach.

15.
J Innov Card Rhythm Manag ; 14(4): 5410-5419, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37143577

RESUMEN

Ultrasound-guided axillary vein access is an effective alternative to conventional subclavian and cephalic access for cardiac implantable electronic device implantation. The aim of this study was to compare the safety, efficacy, and radiation exposure data of the ultrasound-guided axillary approach with other conventional access techniques. The study population included 130 consecutive patients, stratified as 65 (64% male; median age, 79 years) in the study group and 65 (66% male; median age, 81 years) in the control group. We performed a retrospective not-randomized analysis by comparing ultrasound-guided axillary vein puncture with subclavian and cephalic approaches in order to test the effect on X-ray exposure, total procedure time, and complications. Significant differences were observed in terms of radiation exposure, including fluoroscopy time (median, 95 s [study group] vs. 193 s [control group]; P < .001), air kerma (median, 29 mGy [study group] vs. 55.7 mGy [control group]; P < .001), and dose-area product (median, 8219 mGy·cm2 [study group] vs. 16736 mGy·cm2 [control group]; P < .001). The median procedure time was 45 min in the study group but 50 min in the control group (P < .05). Complications occurred in 6 control group patients (1 urticaria contrast medium-related, 3 pneumothorax, 2 subclavian artery puncture) and 2 study group patients (2 axillary artery puncture). We conclude that the ultrasound-guided axillary venous approach is a fast, feasible, and safe technique for cardiac lead implantation. It allows a significant reduction in fluoroscopy time without prolonging the procedural time. This approach offers direct visualization of the vessel during the puncture, so it can be useful in patients who cannot receive contrast medium, those who require "difficult" thoracic approaches (emphysema, too much or too little fat tissue), or those on anticoagulant therapy.

16.
Int J Urol ; 18(7): 515-20, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21592232

RESUMEN

OBJECTIVES: The occurrence of residual storage symptoms after surgical relief of bladder outlet obstruction as a result of benign prostatic enlargement (BPE) underlines the intricate mechanism involved in lower urinary tract symptoms (LUTS). The aim of the present study was to compare tadalafil with solifenacin in modifying symptoms and uroflowmetric parameters in patients with erectile dysfunction (ED) and residual storage symptoms after prostate surgery. METHODS: From May 2007 to April 2009, we evaluated 68 patients who had undergone prostate surgery at least 6months earlier, and presented with ED and persistence of storage symptoms. A total of 56 patients were randomized to receive tadalafil 5mg (group 1) or solifenacin 5mg (group 2), both given daily for 12weeks. International Prostate Symptoms Score (IPSS), IPSS Quality of Life, International Index of Erectile Function-5 (IIEF-5) and uroflowmetry parameters were collected at baseline and after 12weeks of treatment. RESULTS: A total of 26 patients in group 1 and 25 patients in group 2 completed the study. Each group showed a significant and comparable improvement of urinary symptoms with a decrease of IPSS value. Only in group 1 did the treatment with tadalafil result in a significant increase of IIEF-5. No statistically significant variations were noted in uroflowmetric parameters in both groups. CONCLUSIONS: In patients suffering from ED and storage symptoms after surgical treatment for LUTS-BPE, tadalafil 5mg given once daily for 12weeks provided a comparable improvement in IPSS to solifenacin 5mg given for the same period of time.


Asunto(s)
Carbolinas/administración & dosificación , Disfunción Eréctil/etiología , Complicaciones Posoperatorias/tratamiento farmacológico , Hiperplasia Prostática/cirugía , Quinuclidinas/administración & dosificación , Tetrahidroisoquinolinas/administración & dosificación , Trastornos Urinarios/tratamiento farmacológico , Anciano , Carbolinas/efectos adversos , Humanos , Masculino , Persona de Mediana Edad , Antagonistas Muscarínicos/administración & dosificación , Antagonistas Muscarínicos/efectos adversos , Inhibidores de Fosfodiesterasa 5/administración & dosificación , Inhibidores de Fosfodiesterasa 5/efectos adversos , Estudios Prospectivos , Quinuclidinas/efectos adversos , Succinato de Solifenacina , Encuestas y Cuestionarios , Tadalafilo , Tetrahidroisoquinolinas/efectos adversos , Terapéutica , Trastornos Urinarios/etiología , Urodinámica/efectos de los fármacos
17.
J Nephrol ; 22(2): 273-80, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19384846

RESUMEN

BACKGROUND: We developed a new method that diagnoses when either Na or water alone are altered during electrolyte abnormalities. The aim of this study is to describe the preliminary report of an original method which can give exact or useful calculations even in mixed disorders. METHODS: when NaCl is lost, the plasma Cl (PCl) to plasma Na (PNa) ratio falls from 0.75 (the normal value) toward zero, the ratio of plasma anions other than Cl (POAN) to PNa rises toward unity and POAN/PPCl toward infinity. With subscript 0 or normal values and subscript 1 for those during derangement, PCl1/PCl0 falls below unity, while POAN 1 /POAN 0 rises above unity in these hyponatremic disorders. Based on these changes, we developed exact mathematical formulas to compute alterations in solvent and solutes. The boundary conditions of applicability were computer modeled. RESULTS: regression coefficients between true data fed oo the computer and those calculated with our formulas were 1.00 when the boundary conditions were entirely met (R2=1.00, <0.0001) and 0.93-0.96 (R2>0.94<0.99, <0.001) when the boundary conditions were allowed to extend beyond their limits of exclusive mathematical validity. The method was extended to patients whose data satisfied the boundary conditions. The results show that the computations satisfactorily predict the exact measurements obtained by the change in body weight (R2=0.61, <0.001). CONCLUSIONS: This new method represents useful adjunct in evaluating and treating hyponatremias. Although its validity is limited to rather strict boundary conditions, it represents an original way to evaluate mixed solvent/solute derangements.


Asunto(s)
Agua Corporal/fisiología , Cloruros/sangre , Simulación por Computador , Electrólitos/sangre , Hiponatremia/metabolismo , Sodio/sangre , Presión Sanguínea/fisiología , Peso Corporal , Humanos , Hiponatremia/fisiopatología
18.
Nephrology (Carlton) ; 14(3): 338-44, 2009 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19178646

RESUMEN

AIM: To avoid electrolyte derangements during correction of hyperosmolar coma (HC), PNa(PREDICTED) at the end of correction is presently estimated from plasma glucose (P(G), mM/L). When the rise in plasma osmolality (Posm) is entirely due to glucose addition (G(A), mM) to the extracellular volume (ECV), this PNa prediction can be improved by correctly estimating G(A) and any associated water loss (DeltaV), while excluding any concomitant Na loss (DeltaNa). METHODS: Indicating with (0) the normal conditions, with (1) the HC,DeltaPosm=P(G1)xECV1 establishes an exclusive G(A) accumulation. We derived the equations for computing G(A), DeltaV and PNa(PREDICTED). Computer simulations of HC were performed by adding the known G(A) while subtracting the known DeltaV and DeltaNa in different combinations, obtaining exact values of PNa(1) and P(G1). Applying our formulas, we recognized and discarded all cases with concomitant DeltaNa, and we computed G(A), DeltaV and PNa (PREDICTED) from PNa(1) and P(G1), as if they had been measured in patients. We extended these same calculation algorithms to 68 patients with HC. RESULTS: In computer simulations, true and calculated G(A), DeltaV and PNa(PREDICTED) were identical, such that regression and correlation coefficients were 1 (P < 0.0001). Out of the 68 patients recruited, 13 fulfilled the boundary conditions of an exclusive G(A) addition. The true values, obtained by balance studies performed on these patients, were not different from and significantly correlated with the calculated data (R(2) = 0.99, P < 0.001). CONCLUSION: Our new model system for HC and the new formulas improve to near exactness the accuracy in estimating PNa(PREDICTED), helping the physician to avoid unwanted electrolyte derangements during treatment.


Asunto(s)
Simulación por Computador , Glucosa/metabolismo , Coma Hiperglucémico Hiperosmolar no Cetósico/etiología , Humanos , Análisis de Regresión , Sodio/metabolismo
19.
Arch Ital Urol Androl ; 81(4): 209-11, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20608142

RESUMEN

The objective of the present study was to evaluate the efficacy of the periprostatic nerve block (PNB) of the prostate-vesicular junction with low volume and high concentration of anesthetics in relieving pain during prostate biopsy. Two hundred and twenty patients were enrolled and randomized to receive PNB with 5 ml 2% lidocaine (group 1110 pts) and PNB with 5 ml 2% mepivacaine (group 2, 110 pts). The anesthetic was administered through a single puncture on each side at the prostate-vesicular junction using a 22-gauge needle. All patients filled in a ten visual analogue pain score scale (VAS) from 0 = no discomfort to 10 = severe pain, for the assessment of pain experienced during biopsy. The two groups were homogeneous concerning the anthropometrical data. The mean pain score with lidocaine was 1.4 +/- 1.02 (CI 95% = 1.53 to 3.57) and with mepivacaine was 1.3 +/- 1.06 (CI 95% = 2.66 +/- 4.84) with no statistical significant difference between groups (p = 0.43). No general or local adverse effects were observed between the anaesthetics. The use of a low volume (2.5 ml on each side) and high concentration (2%) of local anesthetics (lidocaine/mepivacaine) almost completely suppresses pain and discomfort associated with prostate biopsy. The anatomy of neurovascular bundle regions appears favourable to the administration of small amounts of anesthetic.


Asunto(s)
Anestésicos Locales/uso terapéutico , Biopsia con Aguja , Lidocaína/uso terapéutico , Mepivacaína/uso terapéutico , Bloqueo Nervioso/métodos , Neoplasias de la Próstata/diagnóstico por imagen , Neoplasias de la Próstata/patología , Anciano , Anestésicos Locales/administración & dosificación , Humanos , Lidocaína/administración & dosificación , Masculino , Mepivacaína/administración & dosificación , Persona de Mediana Edad , Dimensión del Dolor , Satisfacción del Paciente , Ultrasonografía Intervencional
20.
Nanoscale Res Lett ; 14(1): 336, 2019 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-31659492

RESUMEN

Taking inspiration from the structure of diatom algae frustules and motivated by the need for new detecting strategies for emerging nanopollutants in water, we analyze the potential of nanoporous silica tablets as metering devices for the concentration of biomolecules or nanoparticles in water. The concept relies on the different diffusion behavior that water molecules exhibit in bulk and nanoconfined conditions, e.g., in nanopores. In this latter situation, the self-diffusion coefficient of water reduces according to the geometry and surface properties of the pore and to the concentration of suspended biomolecules or nanoparticles in the pore, as extensively demonstrated in a previous study. Thus, for a given pore-liquid system, the self-diffusivity of water in nanopores filled with biomolecules or nanoparticles provides an indirect measure of their concentration. Using molecular dynamics and previous results from the literature, we demonstrate the correlation between the self-diffusion coefficient of water in silica nanopores and the concentration of proteins or nanoparticles contained therein. Finally, we estimate the time required for the nanoparticles to fill the nanopores, in order to assess the practical feasibility of the overall nano-metering protocol. Results show that the proposed approach may represent an alternative method for assessing the concentration of some classes of nanopollutants or biomolecules in water.

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