Caracterización y tratamiento de la enuresis en pacientes con vejiga hiperactiva / Characterization and treatment of enuresis in overactive bladder patients

Objetivos: Definir los tipos de enuresis de los pacientes con vejiga hiperactiva (VH) y estudiar su respuesta al tratamiento vesical diurno. Material y métodos. Estudio prospectivo y multicéntrico: pacientes con VH y enuresis, tratados con anticolinérgicos o neuromodulación durante 3 meses (2019-2021). Recogimos variables obtenidas del calendario miccional, cuestionario PLUTSS (Pediatric Lower Urinary Tract Score System), y relacionadas con la enuresis. Generamos 2 grupos de estudio: enuresis primaria (EP) y enuresis secundaria (ES). Consideramos respuesta parcial enurética (RPE) a la reducción del valor de enuresis inicial en más de un 50% y respuesta completa (RCE) el 100%. Finalmente realizamos un análisis multivariante para detectar factores predictivos independientes de RCE. Resultados. Incluimos 152 pacientes con VH, 109 de los cuales presentaban enuresis (71,7%): 29 ES (26,7%) y 80 EP (73,3%). El valor PLUTSS fue mayor en pacientes con EP que en ES (20,8 vs. 17,2, p= 0,001.) La RPE y la RCE fueron significativamente mayores en el grupo de ES (55,2% vs. 15%, p= 0,000 en RPE y 48,3% vs. 5%, p= 0,000 en RCE). En el análisis multivariante se identificó que los pacientes con ES tienen una probabilidad de responder al tratamiento vesical diurno 50 veces superior que los pacientes con EP (OR 49,79, IC95% 6,73-36,8). Conclusiones. La mayoría de niños con VH tienen una EP y no secundaria, por lo que generalmente la enuresis de estos pacientes no responde al tratamiento vesical diurno. Es importante caracterizar el tipo de enuresis de los niños con VH para plantear su tratamiento de forma adecuada.(AU)

Objective: To define the types of overactive bladder (OAB) patient enuresis and study daytime bladder treatment response. Materials and methods. A prospective, multi-center study of OAB patients with enuresis treated with anticholinergics or neuromodulation over 3 months from 2019 to 2021 was carried out. Variables achieved from the voiding calendar and PLUTSS (Pediatric Lower Urinary Tract Score System), as well as enuresis-related variables, were collected. Two study groups were created – primary enuresis (PE) and secondary enuresis (SE). Partial enuretic response (PER) was defined as a >50% reduction in baseline enuresis, and complete enuretic response (CER) as a 100% reduction. A multivariate analysis was eventually conducted to detect CER independent predictive factors. Results. 152 OAB patients were included. 109 of them (71.7%) had enuresis – 29 (26.7%) SE and 80 (73.3%) PE. PLUTSS score was higher in PE patients than in SE patients (20.8 vs. 17.2; p= 0.001). PER and CER were significantly higher in the SE group (55.2% vs. 15%; p= 0.000 in PER, and 48.3% vs. 5%; p= 0.000 in CER). In the multivariate analysis, SE patients demonstrated to have a 50-fold increased probability of responding to daytime bladder treatment than PE patients (OR: 49.79; 95%CI: 6.73-36.8). Conclusions. Most OAB children have PE and not SE, which explains why enuresis does not typically respond to daytime bladder treatment. Characterizing the type of enuresis in OAB children is important to adequately approach treatment.(AU)

Characterization and treatment of enuresis in overactive bladder patients. / Caracterización y tratamiento de la enuresis en pacientes con vejiga hiperactiva.

OBJECTIVE: To define the types of overactive bladder (OAB) patient enuresis and study daytime bladder treatment response. MATERIALS AND METHODS: A prospective, multi-center study of OAB patients with enuresis treated with anticholinergics or neuromodulation over 3 months from 2019 to 2021 was carried out. Variables achieved from the voiding calendar and PLUTSS (Pediatric Lower Urinary Tract Score System), as well as enuresis-related variables, were collected. Two study groups were created -primary enuresis (PE) and secondary enuresis (SE). Partial enuretic response (PER) was defined as a > 50% reduction in baseline enuresis, and complete enuretic response (CER) as a 100% reduction. A multivariate analysis was eventually conducted to detect CER independent predictive factors. RESULTS: 152 OAB patients were included. 109 of them (71.7%) had enuresis -29 (26.7%) SE and 80 (73.3%) PE. PLUTSS score was higher in PE patients than in SE patients (20.8 vs. 17.2; p= 0.001). PER and CER were significantly higher in the SE group (55.2% vs. 15%; p= 0.000 in PER, and 48.3% vs. 5%; p= 0.000 in CER). In the multivariate analysis, SE patients demonstrated to have a 50-fold increased probability of responding to daytime bladder treatment than PE patients (OR: 49.79; 95%CI: 6.73-36.8). CONCLUSIONS: Most OAB children have PE and not SE, which explains why enuresis does not typically respond to daytime bladder treatment. Characterizing the type of enuresis in OAB children is important to adequately approach treatment.

OBJETIVOS: Definir los tipos de enuresis de los pacientes con vejiga hiperactiva (VH) y estudiar su respuesta al tratamiento vesical diurno. MATERIAL Y METODOS: Estudio prospectivo y multicéntrico: pacientes con VH y enuresis, tratados con anticolinérgicos o neuromodulación durante 3 meses (2019-2021). Recogimos variables obtenidas del calendario miccional, cuestionario PLUTSS (Pediatric Lower Urinary Tract Score System), y relacionadas con la enuresis. Generamos 2 grupos de estudio: enuresis primaria (EP) y enuresis secundaria (ES). Consideramos respuesta parcial enurética (RPE) a la reducción del valor de enuresis inicial en más de un 50% y respuesta completa (RCE) el 100%. Finalmente realizamos un análisis multivariante para detectar factores predictivos independientes de RCE. RESULTADOS: Incluimos 152 pacientes con VH, 109 de los cuales presentaban enuresis (71,7%): 29 ES (26,7%) y 80 EP (73,3%). El valor PLUTSS fue mayor en pacientes con EP que en ES (20,8 vs. 17,2, p= 0,001.) La RPE y la RCE fueron significativamente mayores en el grupo de ES (55,2% vs. 15%, p= 0,000 en RPE y 48,3% vs. 5%, p= 0,000 en RCE). En el análisis multivariante se identificó que los pacientes con ES tienen una probabilidad de responder al tratamiento vesical diurno 50 veces superior que los pacientes con EP (OR 49,79, IC95% 6,73-36,8). CONCLUSIONES: La mayoría de niños con VH tienen una EP y no secundaria, por lo que generalmente la enuresis de estos pacientes no responde al tratamiento vesical diurno. Es importante caracterizar el tipo de enuresis de los niños con VH para plantear su tratamiento de forma adecuada.

Efficacy of sacral transcutaneous electrical nerve stimulation in patients with overactive bladder refractory to anticholinergic treatment: a prospective multi-center study. / Eficacia de la electroestimulación transcutánea sacra en pacientes con vejiga hiperactiva refractarios a fármacos anticolinérgicos. Estudio prospectivo y multicéntrico.

OBJECTIVE: To determine whether sacral transcutaneous electrical nerve stimulation (S-TENS) is an effective treatment in patients refractory to anticholinergic drugs (Achs). MATERIALS AND METHODS: A prospective multi-center study of patients with overactive bladder (OB) refractory to Achs treated with S-TENS from 2018 to 2021 was carried out. S-TENS was applied over 3 months. Symptom progression was assessed using the voiding calendar and the Pediatric Lower Urinary Tract Symptoms Score (PLUTSS), excluding questions 3 and 4 -referring to enuresis- so that progression of daytime symptoms only (LUTS variable) was analyzed. RESULTS: 66 patients -50% of whom were female- were included, with a mean age of 9.5 years (range: 5-15). S-TENS significantly lowered PLUTSS (19.1 baseline vs. 9.5 final, p< 0.001) and LUTS (13.1 baseline vs. 4.8 final, p< 0.001). It also reduced the number of mictions (8.5 baseline vs. 6.4 final, p< 0.001), while increasing urine volume in the voiding records (214 ml baseline vs. 258 ml final, p< 0.001). Enuresis was the only variable refractory to S-TENS. Complication rate was 3% (2 patients with dermatitis in the S-TENS application area). CONCLUSIONS: S-TENS is effective and safe in the short-term in patients with OB refractory to Achs. Further studies assessing long-term efficacy and potential relapses are required.

OBJETIVOS: Determinar si la electroterapia nerviosa transcutánea a nivel sacro (TENS-S) es un tratamiento efectivo en pacientes refractarios a fármacos anticolinérgicos (Ach). MATERIAL Y METODOS: Estudio prospectivo y multicéntrico: pacientes con VH refractaria a Ach tratados con TENS-S entre 2018-2021. El TENS-S se aplicó durante 3 meses. La evolución sintomática fue evaluada utilizando el calendario miccional y el cuestionario PLUTSS (Pediatric Lower Urinary Tract Symptoms Score), pero excluyendo sus preguntas 3 y 4 (referidas a la enuresis) para analizar solamente la evolución de la sintomatología diurna (variable LUTS). RESULTADOS: Fueron incluidos 66 pacientes (50% niñas), con una edad media de 9,5 años (rango: 5-15). El TENS-S disminuyó significativamente el PLUTSS (19,1 inicial vs 9,5 final, p< 0,001) y el LUTS (13,1 inicial vs 4,8 final, p< 0,001). Además, redujo el número de micciones (8,5 inicial vs 6,4 final, p< 0,001) y aumentó el volumen de orina en los registros miccionales (214 ml inicial vs 258 ml final, p< 0,001). La enuresis fue la única variable refractaria al TENS-S. La tasa de complicaciones fue del 3% (2 pacientes, dermatitis en el área de aplicación del TENS-S). CONCLUSIONES: El TENS-S es efectivo y seguro a corto plazo en pacientes con VH refractarios a los Ach. Deben realizarse estudios para evaluar la eficacia a largo plazo y posibles recaídas.

Eficacia de la electroestimulación transcutánea sacra en pacientes con vejiga hiperactiva refractarios a fármacos anticolinérgicos. Estudio prospectivo y multicéntrico / Efficacy of sacral transcutaneous electrical nerve stimulation in patients with overactive bladder refractory to anticholinergic treatment: a prospective multi-center study

Objetivos: Determinar si la electroterapia nerviosa transcutánea anivel sacro (TENS-S) es un tratamiento efectivo en pacientes refractariosa fármacos anticolinérgicos (Ach).Material y métodos: Estudio prospectivo y multicéntrico: pacientes con VH refractaria a Ach tratados con TENS-S entre 2018-2021. El TENS-S se aplicó durante 3 meses. La evolución sintomática fueevaluada utilizando el calendario miccional y el cuestionario PLUTSS(Pediatric Lower Urinary Tract Symptoms Score), pero excluyendo suspreguntas 3 y 4 (referidas a la enuresis) para analizar solamente laevolución de la sintomatología diurna (variable LUTS).Resultados: Fueron incluidos 66 pacientes (50% niñas), con unaedad media de 9,5 años (rango: 5-15). El TENS-S disminuyó significativamente el PLUTSS (19,1 inicial vs 9,5 final, p< 0,001) y el LUTS (13,1inicial vs 4,8 final, p< 0,001). Además, redujo el número de micciones(8,5 inicial vs 6,4 final, p< 0,001) y aumentó el volumen de orina enlos registros miccionales (214 ml inicial vs 258 ml final, p< 0,001). Laenuresis fue la única variable refractaria al TENS-S. La tasa de complicaciones fue del 3% (2 pacientes, dermatitis en el área de aplicacióndel TENS-S). Conclusiones: El TENS-S es efectivo y seguro a corto plazo enpacientes con VH refractarios a los Ach. Deben realizarse estudios paraevaluar la eficacia a largo plazo y posibles recaídas.(AU)

Objective: To determine whether sacral transcutaneous electricalnerve stimulation (S-TENS) is an effective treatment in patients refractory to anticholinergic drugs (Achs).Materials and methods. A prospective multi-center study of patients with overactive bladder (OB) refractory to Achs treated with S-TENS from 2018 to 2021 was carried out. S-TENS was applied over 3months. Symptom progression was assessed using the voiding calendarand the Pediatric Lower Urinary Tract Symptoms Score (PLUTSS),excluding questions 3 and 4 –referring to enuresis– so that progressionof daytime symptoms only (LUTS variable) was analyzed. Results: 66 patients –50% of whom were female– were included,with a mean age of 9.5 years (range: 5-15). S-TENS significantly lowered PLUTSS (19.1 baseline vs. 9.5 final, p< 0.001) and LUTS (13.1baseline vs. 4.8 final, p< 0.001). It also reduced the number of mictions(8.5 baseline vs. 6.4 final, p< 0.001), while increasing urine volume inthe voiding records (214 ml baseline vs. 258 ml final, p< 0.001). Enuresiswas the only variable refractory to S-TENS. Complication rate was 3%(2 patients with dermatitis in the S-TENS application area).Conclusions: S-TENS is effective and safe in the short-term inpatients with OB refractory to Achs. Further studies assessing long-termefficacy and potential relapses are required.(AU)

La queratodermia acuagénica: actualización terapéutica / Aquagenic Keratoderma: Treatment Update

La queratodermia acuagénica (QA) es una afectación dermatológica adquirida poco frecuente que se caracteriza por la aparición de edema y pápulas blanquecinas-translúcidas desencadenado por la inmersión o contacto con el agua. Se han descrito casos asociados a fármacos, hiperhidrosis y a fibrosis quística. Los objetivos del estudio son evaluar la efectividad de los distintos tratamientos existentes para la QA. Realizamos una revisión de la literatura existente al respecto hasta el momento, incluyendo series de casos y reportes de caso. El tratamiento de la QA es efectivo en las formas asociadas a hiperhidrosis. La iontoforesis del agua del grifo, la simpatectomía torácica endoscópica, las inyecciones de toxina botulínica y la oxibutinina son efectivas en las formas refractarias. La aplicación tópica de ácido salicílico o sales de aluminio es efectiva, pero resulta poco eficaz como tratamiento de mantenimiento. Probablemente la mejor alternativa para el tratamiento de la QA sea la oxibutinina 5mg/día vo. Se ha observado que los efectos fisiopatológicos de los antiinflamatorios no esteroideos en la QA podrían justificar el uso de las prostaglandinas como un tratamiento dirigido de la enfermedad. Se necesitan estudios adicionales para fortalecer estas deducciones y abordar las incertidumbres restantes (AU)

Aquagenic keratoderma is an uncommon acquired dermatosis characterized by edema and whitish-translucent papules triggered by immersion or contact with water. Cases have been described in association with certain medications, hyperhidrosis, and cystic fibrosis. The aim of this review is to evaluate the effectiveness of different treatments for aquagenic keratoderma. We reviewed the literature and analyzed treatments for aquagenic keratoderma described in case series and reports. Aquagenic keratoderma associated with hyperhidrosis can be treated effectively. Tap water iontophoresis, endoscopic thoracic sympathectomy, botulinum toxin injections, and oxybutynin are effective against refractory forms. Topical salicylic acid and aluminum salts are effective, but of little value as maintenance therapy. Oral oxybutynin 5 mg/d is probably the best option for treating aquagenic keratoderma. The reported pathophysiological effects of nonsteroidal anti inflammatory drugs in this setting suggest that the use of prostaglandins might be justified. Additional studies are needed to investigate these hypotheses and resolve other questions (AU)

[Translated article] Aquagenic Keratoderma: Treatment Update / La queratodermia acuagénica: actualización terapéutica

Aquagenic keratoderma is an uncommon acquired dermatosis characterized by edema and whitish-translucent papules triggered by immersion or contact with water. Cases have been described in association with certain medications, hyperhidrosis, and cystic fibrosis. The aim of this review is to evaluate the effectiveness of different treatments for aquagenic keratoderma. We reviewed the literature and analyzed treatments for aquagenic keratoderma described in case series and reports. Aquagenic keratoderma associated with hyperhidrosis can be treated effectively. Tap water iontophoresis, endoscopic thoracic sympathectomy, botulinum toxin injections, and oxybutynin are effective against refractory forms. Topical salicylic acid and aluminum salts are effective, but of little value as maintenance therapy. Oral oxybutynin 5 mg/d is probably the best option for treating aquagenic keratoderma. The reported pathophysiological effects of nonsteroidal anti inflammatory drugs in this setting suggest that the use of prostaglandins might be justified. Additional studies are needed to investigate these hypotheses and resolve other questions (AU)

La queratodermia acuagénica (QA) es una afectación dermatológica adquirida poco frecuente que se caracteriza por la aparición de edema y pápulas blanquecinas-translúcidas desencadenado por la inmersión o contacto con el agua. Se han descrito casos asociados a fármacos, hiperhidrosis y a fibrosis quística. Los objetivos del estudio son evaluar la efectividad de los distintos tratamientos existentes para la QA. Realizamos una revisión de la literatura existente al respecto hasta el momento, incluyendo series de casos y reportes de caso. El tratamiento de la QA es efectivo en las formas asociadas a hiperhidrosis. La iontoforesis del agua del grifo, la simpatectomía torácica endoscópica, las inyecciones de toxina botulínica y la oxibutinina son efectivas en las formas refractarias. La aplicación tópica de ácido salicílico o sales de aluminio es efectiva, pero resulta poco eficaz como tratamiento de mantenimiento. Probablemente la mejor alternativa para el tratamiento de la QA sea la oxibutinina 5mg/día vo. Se ha observado que los efectos fisiopatológicos de los antiinflamatorios no esteroideos en la QA podrían justificar el uso de las prostaglandinas como un tratamiento dirigido de la enfermedad. Se necesitan estudios adicionales para fortalecer estas deducciones y abordar las incertidumbres restantes (AU)

Aquagenic Keratoderma: Treatment Update. / La queratodermia acuagénica: actualización terapéutica.

Aquagenic keratoderma is an uncommon acquired dermatosis characterized by edema and whitish-translucent papules triggered by immersion or contact with water. Cases have been described in association with certain medications, hyperhidrosis, and cystic fibrosis. The aim of this review is to evaluate the effectiveness of different treatments for aquagenic keratoderma. We reviewed the literature and analyzed treatments for aquagenic keratoderma described in case series and reports. Aquagenic keratoderma associated with hyperhidrosis can be treated effectively. Tap water iontophoresis, endoscopic thoracic sympathectomy, botulinum toxin injections, and oxybutynin are effective against refractory forms. Topical salicylic acid and aluminum salts are effective, but of little value as maintenance therapy. Oral oxybutynin 5 mg/d is probably the best option for treating aquagenic keratoderma. The reported pathophysiological effects of nonsteroidal anti inflammatory drugs in this setting suggest that the use of prostaglandins might be justified. Additional studies are needed to investigate these hypotheses and resolve other questions.

Regenerative and Resorbable PLA/HA Hybrid Construct for Tendon/Ligament Tissue Engineering.

Tendon and ligament shows extremely limited endogenous regenerative capacity. Current treatments are based on the replacement and or augmentation of the injured tissue but the repaired tissue rarely achieve functionality equal to that of the preinjured tissue. To address this challenge, tissue engineering has emerged as a promising strategy. This study develops a regenerative and resorbable hybrid construct for tendon and ligament engineering. The construct is made up by a hollow poly-lactic acid braid with embedded microspheres carrying cells and an anti-adherent coating, with all the parts being made of biodegradable materials. This assembly intends to regenerate the tissue starting from the interior of the construct towards outside while it degrades. Fibroblasts cultured on poly lactic acid and hyaluronic acid microspheres for 6 h were injected into the hollow braid and the construct was cultured for 14 days. The cells thus transported into the lumen of the construct were able to migrate and adhere to the braid fibers naturally, leading to a homogeneous proliferation inside the braid. Moreover, no cells were found on the outer surface of the coating. Altogether, this study demonstrated that PLA/HA hybrid construct could be a promising material for tendon and ligament repair.

Positioning of the cross-stitch on the modified Kessler core tendon suture.

Cryopreserved human tendons were sutured with different variations of a modified Kessler-type grasping suture in a series of different designs in order to assess the influence of the distance between the cross-stitch on the core suture (5 and 10 mm from the cut tendon edge) on the peripheral suture. An original mathematical model was employed to explain the mechanical behavior (strength, deformation, and distribution of load) of the different suture designs. The effect of the peripheral epitendinous suture, combined with the distance of the core suture, was evaluated. The variation of core suture distance had no relevant consequences on the overall resilience of the design. However, increasing the distance between the cross-stitches of the core suture reduces the deformation that is absorbed not only by the core suture itself but also by the peripheral suture. Adding a peripheral epitendinous suture to a 10-mm design almost doubles the breaking load in absolute values. The mathematical model predicts that the peripheral suture will support a greater load when the distance of the core suture cross-stitches is increased. The evidence level is II.

Noise-induced transitions in rugged energy landscapes.

We consider the problem of an overdamped Brownian particle moving in multiscale potential with N+1 characteristic length scales: the macroscale and N separated microscales. We show that the coarse-grained dynamics is given by an overdamped Langevin equation with respect to the free energy and with a space-dependent diffusion tensor, the calculation of which requires the solution of N fully coupled Poisson equations. We study in detail the structure of the bifurcation diagram for one-dimensional problems, and we show that the multiscale structure in the potential leads to hysteresis effects and to noise-induced transitions. Furthermore, we obtain an explicit formula for the effective diffusion coefficient for a self-similar separable potential, and we investigate the limit of infinitely many small scales.

Scaffolds of Hyaluronic Acid-Poly(Ethyl Acrylate) Interpenetrating Networks: Characterization and In Vitro Studies.

Hyaluronic acid (HA) provides many advantages to regenerative implants through its bioactive properties, but it also has many limitations as a biomaterial if it is not chemically modified. In order to overcome some of these limitations, HA has been combined with poly(ethyl acrylate) in the form of interpenetrating polymeric networks (IPNs), in which the HA network is crosslinked with divinyl sulfone. Scaffolds of this IPN have been produced through a template-leaching methodology, and their properties have been compared with those of single-network scaffolds made of either PEA or crosslinked HA. A fibroblast cell line has been used to assess the in vitro performance of the scaffolds, revealing good cell response and a differentiated behavior on the IPN surface when compared to the individual polymers. Altogether, the results confirm that this type of material offers an interesting microenvironment for cells, which can be further improved toward its potential use in medical implants.

Scaffolds based on hyaluronan and carbon nanotubes gels.

Physico-chemical and mechanical properties of hyaluronic acid/carbon nanotubes nanohybrids have been correlated with the proportion of inorganic nanophase and the preparation procedure. The mass fraction of -COOH functionalized carbon nanotubes was varied from 0 to 0.05. Hyaluronic acid was crosslinked with divinyl sulfone to improve its stability in aqueous media and allow its handling as a hydrogel. A series of samples was dried by lyophilization to obtain porous scaffolds whereas another was room-dried allowing the collapse of the hybrid structures. The porosity of the former, together with the tighter packing of hyaluronic acid chains, results in a lower water absorption and lower mechanical properties in the swollen state, because of the easier water diffusion. The presence of even a small amount of carbon nanotubes (mass fraction of 0.05) limits even more the swelling of the matrix, owing probably to hybrid interactions. These nanohybrids do not seem to degrade significantly during 14 days in water or enzymatic medium.

Dynamics of Fattening and Thinning 2D Sessile Droplets.

We investigate the dynamics of a droplet on a planar substrate as the droplet volume changes dynamically due to liquid being pumped in or out through a pore. We adopt a diffuse-interface formulation which is appropriately modified to account for a localized inflow-outflow boundary condition (the pore) at the bottom of the droplet, hence allowing to dynamically control its volume, as the droplet moves on a flat substrate with a periodic chemical pattern. We find that the droplet undergoes a stick-slip motion as the volume is increased (fattening droplet) which can be monitored by tracking the droplet contact points. If we then switch over to outflow conditions (thinning droplet), the droplet follows a different path (i.e., the distance of the droplet midpoint from the pore location evolves differently), giving rise to a hysteretic behavior. By means of geometrical arguments, we are able to theoretically construct the full bifurcation diagram of the droplet equilibria (positions and droplet shapes) as the droplet volume is changed, finding excellent agreement with time-dependent computations of our diffuse-interface model.

Influence of scaffold morphology on co-cultures of human endothelial and adipose tissue-derived stem cells.

The interior of tissue engineering scaffolds must be vascularizable and allow adequate nutrients perfusion in order to ensure the viability of the cells colonizing them. The promotion of rapid vascularization of scaffolds is critical for thick artificial constructs. In the present study co-cultures of human endothelial and adipose tissue-derived stem cells have been performed in poly(ethyl acrylate) scaffolds with two different pore structures: grid-like (PEA-o) or sponge-like (PEA-s), in combination with a self-assembling peptide gel filling the pores, which aims to mimic the physiological niche. After 2 and 7 culture days, cell adhesion, proliferation and migration, the expression of cell surface markers like CD31 and CD90 and the release of VEGF were assessed by means of immunocytochemistry, scanning electronic microscopy, flow cytometry and ELISA analyses. The study demonstrated that PEA-s scaffolds promoted greater cell organization into tubular-like structures than PEA-o scaffolds, and this was enhanced by the presence of the peptide gel. Paracrine signaling from adipose cells significantly improved endothelial cell viability, proving the advantageous combination of this system for obtaining easily vascularizable tissue engineered grafts. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 1523-1533, 2016.

Topologically controlled hyaluronan-based gel coatings of hydrophobic grid-like scaffolds to modulate drug delivery.

Scaffolds based on poly(ethyl acrylate) having interwoven channels were coated with a hyaluronan (HA) hydrogel to be used in tissue engineering applications. Controlled typologies of coatings evolving from isolated aggregates to continuous layers, which eventually clog the channels, were obtained by using hyaluronan solutions of different concentrations. The efficiency of the HA loading was determined using gravimetric and thermogravimetric methods, and the hydrogel loss during the subsequent crosslinking process was quantified, seeming to depend on the mass fraction of hyaluronan initially incorporated to the pores. The effect of the topologically different coatings on the scaffolds, in terms of mechanical properties and swelling at equilibrium under different conditions was evaluated and correlated with the hyaluronan mass fraction. The potential of these hydrogel coatings as vehicle for controlled drug release from the scaffolds was validated using a protein model.

Hydrophilic surface modification of acrylate-based biomaterials.

Acrylic polymers have proved to be excellent with regard to cell adhesion, colonization and survival, in vitro and in vivo. Highly ordered and regular pore structures thereof can be produced with the help of polyamide templates, which are removed with nitric acid. This treatment converts a fraction of the ethyl acrylate side groups into acrylic acid, turning poly(ethyl acrylate) scaffolds into a more hydrophilic and pH-sensitive substrate, while its good biological performance remains intact. To quantify the extent of such a modification, and be able to characterize the degree of hydrophilicity of poly(ethyl acrylate), poly(ethyl acrylate) was treated with acid for different times (four, nine and 17 days), and compared with poly(acrylic acid) and a 90/10%wt. EA/AAc copolymer (P(EA-co-AAc)). The biological performance was also assessed for samples immersed in acid up to four days and the copolymer, and it was found that the incorporation of acidic units on the material surface was not prejudicial for cells. This surface modification of 3D porous hydrophobic scaffolds makes easier the wetting with culture medium and aqueous solutions in general, and thus represents an advantage in the manageability of the scaffolds.

Schwann-cell cylinders grown inside hyaluronic-acid tubular scaffolds with gradient porosity.

Cell transplantation therapies in the nervous system are frequently hampered by glial scarring and cell drain from the damaged site, among others. To improve this situation, new biomaterials may be of help. Here, novel single-channel tubular conduits based on hyaluronic acid (HA) with and without poly-l-lactide acid fibers in their lumen were fabricated. Rat Schwann cells were seeded within the conduits and cultured for 10days. The conduits possessed a three-layered porous structure that impeded the leakage of the cells seeded in their interior and made them impervious to cell invasion from the exterior, while allowing free transport of nutrients and other molecules needed for cell survival. The channel's surface acted as a template for the formation of a cylindrical sheath-like tapestry of Schwann cells continuously spanning the whole length of the lumen. Schwann-cell tubes having a diameter of around 0.5mm and variable lengths can thus be generated. This structure is not found in nature and represents a truly engineered tissue, the outcome of the specific cell-material interactions. The conduits might be useful to sustain and protect cells for transplantation, and the biohybrids here described, together with neuronal precursors, might be of help in building bridges across significant distances in the central and peripheral nervous system. STATEMENT OF SIGNIFICANCE: The paper entitled "Schwann-cell cylinders grown inside hyaluronic-acid tubular scaffolds with gradient porosity" reports on the development of a novel tubular scaffold and on how this scaffold acts on Schwann cells seeded in its interior as a template to produce macroscopic hollow continuous cylinders of tightly joined Schwann cells. This cellular structure is not found in nature and represents a truly engineered novel tissue, which obtains as a consequence of the specific cell-material interactions within the scaffold.

Data-driven coarse graining in action: Modeling and prediction of complex systems.

In many physical, technological, social, and economic applications, one is commonly faced with the task of estimating statistical properties, such as mean first passage times of a temporal continuous process, from empirical data (experimental observations). Typically, however, an accurate and reliable estimation of such properties directly from the data alone is not possible as the time series is often too short, or the particular phenomenon of interest is only rarely observed. We propose here a theoretical-computational framework which provides us with a systematic and rational estimation of statistical quantities of a given temporal process, such as waiting times between subsequent bursts of activity in intermittent signals. Our framework is illustrated with applications from real-world data sets, ranging from marine biology to paleoclimatic data.

Controlling spatiotemporal chaos in active dissipative-dispersive nonlinear systems.

We present an alternative methodology for the stabilization and control of infinite-dimensional dynamical systems exhibiting low-dimensional spatiotemporal chaos. We show that with an appropriate choice of time-dependent controls we are able to stabilize and/or control all stable or unstable solutions, including steady solutions, traveling waves (single and multipulse ones or bound states), and spatiotemporal chaos. We exemplify our methodology with the generalized Kuramoto-Sivashinsky equation, a paradigmatic model of spatiotemporal chaos, which is known to exhibit a rich spectrum of wave forms and wave transitions and a rich variety of spatiotemporal structures.

New semi-biodegradable materials from semi-interpenetrated networks of poly(ϵ-caprolactone) and poly(ethyl acrylate).

Semi-degradable materials may have many applications. Here poly(ethyl acrylate) and poly(ϵ-caprolactone) were combined as semi-interpenetrated networks, and thoroughly characterized in terms of final composition, interactions between components, wettability, and mechanical properties. PCL modulates the mechanical properties of the PEA elastomeric network. Cultures of fibroblasts and adipose-tissue derived stem cells showed excellent biological performance of the materials. The results are relevant for applications seeking materials leaving a permanent supporting skeleton after the partial degradation, as in patches for cardiac regeneration or in abdominal wall meshes.