Los ámbitos centrales de ciudades como Granada están sometidos a fuertes presiones del mercado turístico y sufren la amenaza constante de la gentrificación, la pérdida de diversidad social, y el ...deterioro y pérdida de carácter de su espacio urbano. Para contrarrestar esto, el urbanismo necesita aprovechar las potencialidades que posee la ciudad histórica, máxime en contextos como el español, donde los instrumentos y las políticas adecuadas de regeneración urbana vienen resultando insuficientes, principalmente desde la crisis de la segunda década del siglo XXI, agravada por la pandemia de la Covid19. Por ello, creemos obligada la optimización de sus recursos turísticos, dándole al patrimonio el papel urbano de activación y dinamización que es capaz de asumir. La investigación trabaja el potencial estratégico del patrimonio arquitectónico para la regeneración urbana integral, desde una perspectiva espacial, funcional y paisajística. Se parte de un conjunto de claves que disciplinar e internacionalmente se vienen poniendo en marcha en las últimas décadas para la interpretación y puesta en valor de la “ciudad-patrimonio”, consideraciones que buscan orientar la vinculación de esta arquitectura catalogada entre sí y con su entorno espacial: el turismo urbano, espacio público central como lugar flexible y compartido, los efectos de la gentrificación, la paseabilidad, etc. Situados en Granada, se analiza el vaciamiento poblacional de su centro, la estandarización y pérdida de calidad de su espacio público, su evidente tematización y la falta de perspectiva integral del planeamiento desarrollado, para plantear la configuración de vinculaciones diacrónicas, reflejo de la evolución de la ciudad a través del tiempo, mediante una aproximación cartográfica, un análisis funcional y una caracterización patrimonial que prioriza los entornos. Se propone así un instrumento de evaluación-diagnóstico que añade nuevos significados a la dimensión patrimonial e intensifica su rol urbano, formulando una propuesta de secuencias, cuya topología es orientada por el juego relacional entre forma urbana, topografía, realidad social y funcional, y paisaje urbano. Se concluye con una sistematización de atributos multidimensionales del patrimonio en la secuencia elegida que posibilite impulsar estrategias futuras de regeneración urbana, superando así la lógica aislada y estática de la visión cataloguista para adentrarse en una re-significación dinámica y relacional.
Objective
To assess the arrhythmic safety profile of the adipose graft transposition procedure (AGTP) and its electrophysiological effects on post-myocardial infarction (MI) scar.
Background
...Myocardial repair is a promising treatment for patients with MI. The AGTP is a cardiac reparative therapy that reduces infarct size and improves cardiac function. The impact of AGTP on arrhythmogenesis has not been addressed.
Methods
MI was induced in 20 swine. Contrast-enhanced magnetic resonance (ce-MRI), electrophysiological study (EPS), and left-ventricular endocardial high-density mapping were performed 15 days post-MI. Animals were randomized 1:1 to AGTP or sham-surgery group and monitored with ECG-Holter. Repeat EPS, endocardial mapping, and ce-MRI were performed 30 days post-intervention. Myocardial SERCA2, Connexin-43 (Cx43), Ryanodine receptor-2 (RyR2), and cardiac troponin-I (cTnI) gene and protein expression were evaluated.
Results
The AGTP group showed a significant reduction of the total infarct scar, border zone and dense scar mass by ce-MRI (
p
= 0.04), and a decreased total scar and border zone area in bipolar voltage mapping (
p
< 0.001). AGTP treatment significantly reduced the area of very-slow conduction velocity (<0.2 m/s) (
p
= 0.002), the number of deceleration zones (
p
= 0.029), and the area of fractionated electrograms (
p
= 0.005). No differences were detected in number of induced or spontaneous ventricular arrhythmias at EPS and Holter-monitoring. SERCA2, Cx43, and RyR2 gene expression were decreased in the infarct core of AGTP-treated animals (
p
= 0.021,
p
= 0.018,
p
= 0.051, respectively).
Conclusion
AGTP is a safe reparative therapy in terms of arrhythmic risk and provides additional protective effect against adverse electrophysiological remodeling in ischemic heart disease.
Thermodynamic Evaluation of 4 Open‐Irrigated Catheters
Introduction
New generation open‐irrigated catheters aim to improve irrigation efficiency. This may change lesion patterns, challenging ...operators. Indeed, safety issues have recently arisen. We aimed to experimentally assess 4 open‐irrigated catheters, comparing lesion size, safety, and heat transfer.
Methods
The thigh lesion model was employed in 6 anesthetized pigs to assess the morphology of perpendicular and tangential lesions (n = 140) created by the newer catheters ThermoCool® SF, CoolFlex™, and Blazer™ Open‐Irrigated, and the standard ThermoCool®, at a constant power of 30 W (60 seconds). To evaluate the propensity for deep‐tissue overheating, a set of 120 applications were performed at 50 W (180 seconds) comparing pop rates. Thermal assessment of the lesion generation process (20 W, 60 seconds, n = 32) was performed with an infrared camera on bovine ventricular tissue.
Results
At 30 W, the newer catheters showed lower temperature readings compared with the ThermoCool®. No major efficacy or safety differences were found at tangential applications; however, at perpendicular applications: (1) the SF at 17 mL/min better preserved the superficial layers and focused its maximum thermal effect deeper, but at recommended flow rates (8 mL/min) it generated the largest superficial lesions; (2) CoolFlex™ created smaller lesions than SF and readily induced steam pops at 50 W without temperature control; and (3) no major differences were found comparing Blazer™ Open‐Irrigated and ThermoCool®.
Conclusions
The lower temperature readings in the newer catheters make them more prone to deliver the maximum programmed power. Under experimental conditions, the SF catheter focuses its maximum effect deeper and the CoolFlex™ can be more prone to induce steam pops at high power settings.
New tools are needed to improve ventricular tachycardia (VT) substrate characterization and optimize outcomes. LI provides biophysical tissue characterization.
The purpose of this study was to test ...local impedance (LI)-based mapping to predict critical ventricular tachycardia components after myocardial infarction (MI).
One month after a nonreperfused anterior MI, endo-epicardial high-density electroanatomic mapping and endocardial LI mapping were performed in 23 Landrace Large X White pigs. LI thresholds were set using the blood pool value to define a 10 Ω range: low (<blood pool −1Ω), intermediate (≥blood pool −1Ω and ≤blood pool +9Ω), and high (normal) tissue resistance (>blood pool +9Ω).
Low LI was detected in low-voltage areas in 100% of cases, but intermediate LI was found in both core (87%) and border zone (12.5%) voltage areas. A total of 17 VTs were induced (VT isthmus identified in 9 animals). VT inducibility was associated with the size of intermediate LI area (OR: 1.19 95% CI: 1.0-1.4; P = 0.039) and the presence of specific LI patterns: LI corridor (OR: 15.0 95% CI: 1.3-169.9; P = 0.029); LI gradient (OR: 30.0 95% CI: 2.1-421.1; P = 0.012), high LI heterogeneity (OR: 21.7 95% CI: 1.8-260.6; P = 0.015), and presence of ≥2 low LI regions (OR: 11.3 95% CI: 1.0-130.2; P = 0.053). Potential VT isthmuses were in areas of intermediate LI and colocalized to LI patterns associated with VT inducibility in all cases (LI corridors or LI gradient). Low LI regions did not actively participate in the VT circuit (0%).
LI mapping is feasible and may add useful characterization of the VT substrate. Specific LI patterns (ie, corridors, gradients) were associated with VT inducibility and colocalized with the VT isthmus, thus representing a potential new target for ablation in substrate-based procedures.
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To accurately recapitulate the heterogeneity of human diseases, animal models require to recreate multiple complex genetic alterations. Here, we combine the RCAS-TVA system with the CRISPR-Cas9 ...genome editing tools for precise modeling of human tumors. We show that somatic deletion in neural stem cells of a variety of known tumor suppressor genes (Trp53, Cdkn2a, and Pten) leads to high-grade glioma formation. Moreover, by simultaneous delivery of pairs of guide RNAs we generate different gene fusions with oncogenic potential, either by chromosomal deletion (Bcan-Ntrk1) or by chromosomal translocation (Myb-Qk). Lastly, using homology-directed-repair, we also produce tumors carrying the homologous mutation to human BRAF V600E, frequently identified in a variety of tumors, including different types of gliomas. In summary, we have developed an extremely versatile mouse model for in vivo somatic genome editing, that will elicit the generation of more accurate cancer models particularly appropriate for pre-clinical testing.
Although cancer tends to affect the elderly, most preclinical studies are carried out in young subjects. In this study, we developed a melanoma-specific cancer immunotherapy that shows efficacy in ...aged but not young hosts by mitigating age-specific tumor-associated immune dysfunction. Both young and aged CD4(+)CD25(hi) regulatory T cells (Treg) exhibited equivalent in vitro T-cell suppression and tumor-associated augmentation in numbers. However, denileukin diftitox (DT)-mediated Treg depletion improved tumor-specific immunity and was clinically effective only in young mice. DT-mediated Treg depletion significantly increased myeloid-derived suppressor cell (MDSC) numbers in aged but not young mice, and MDSC depletion improved tumor-specific immunity and reduced tumor growth in aged mice. Combining Treg depletion with anti-Gr-1 antibody was immunologically and clinically more efficacious than anti-Gr-1 antibody alone in aged B16-bearing mice, similar to Treg depletion alone in young mice. In contrast, DT increased MDSCs in young and aged mice following MC-38 tumor challenge, although effects were greater in aged mice. Anti-Gr-1 boosted DT effects in young but not aged mice. Aged antitumor immune effector cells are therefore competent to combat tumor when underlying tumor-associated immune dysfunction is appropriately mitigated, but this dysfunction varies with tumor, thus also varying responses to immunotherapy. By tailoring immunotherapy to account for age-related tumor-associated immune dysfunctions, cancer immunotherapy for aged patients with specific tumors can be remarkably improved.
CD4(+)CD25(+)Foxp3(+) regulatory T cells (Tregs) are immunopathogenic in cancers by impeding tumor-specific immunity. B7-homologue 1 (B7-H1) (CD274) is a cosignaling molecule with pleiotropic ...effects, including hindering antitumor immunity. In this study, we demonstrate sex-dependent, B7-H1-dependent differences in tumor immunity and response to immunotherapy in a hormone-independent cancer, murine B16 melanoma. Antitumor immunity was better in B7-H1(-/-) females versus males as a result of reduced regulatory T cell function in the B7-H1(-/-) females, and clinical response following B7-H1 blockade as tumor immunotherapy was significantly better in wild-type females than in males, owing to greater B7-H1 blockade-mediated reduction of Treg function in females. Wild-type female Tregs expressed significantly lower B7-H1 versus males but were insensitive to estrogen in vitro. Female B7-H1(-/-) Tregs were exquisitely sensitive to estrogen-mediated functional reduction in vitro, suggesting that B7-H1 effects occur before terminal Treg differentiation. Immune differences were independent of known B7-H1 ligands. Sex-dependent immune differences are seldom considered in designing immune therapy or interpreting immunotherapy treatment results. Our data demonstrate that sex is an important variable in tumor immunopathogenesis and immunotherapy responses through differential Treg function and B7-H1 signaling.
Neuronal computation is achieved through connections of individual neurons into a larger network. To expand the repertoire of endogenous cellular communication, we developed a synthetic, ...photon-assisted synaptic transmission (PhAST) system. PhAST is based on luciferases and channelrhodopsins that enable the transmission of a neuronal state across space, using photons as neurotransmitters. PhAST overcomes synaptic barriers and rescues the behavioral deficit of a glutamate mutant with conditional, calcium-triggered photon emission between two neurons of the Caenorhabditis elegans nociceptive avoidance circuit. To demonstrate versatility and flexibility, we generated de novo synaptic transmission between two unconnected cells in a sexually dimorphic neuronal circuit, suppressed endogenous nocifensive response through activation of an anion channelrhodopsin and switched attractive to aversive behavior in an olfactory circuit. Finally, we applied PhAST to dissect the calcium dynamics of the temporal pattern generator in a motor circuit for ovipositioning. In summary, we established photon-based synaptic transmission that facilitates the modification of animal behavior.
The tumor-suppressor breast cancer 1 (BRCA1) in complex with BRCA1-associated really interesting new gene (RING) domain 1 (BARD1) is a RING-type ubiquitin E3 ligase that modifies nucleosomal histone ...and other substrates. The importance of BRCA1-BARD1 E3 activity in tumor suppression remains highly controversial, mainly stemming from studying mutant ligase-deficient BRCA1-BARD1 species that we show here still retain significant ligase activity. Using full-length BRCA1-BARD1, we establish robust BRCA1-BARD1-mediated ubiquitylation with specificity, uncover multiple modes of activity modulation, and construct a truly ligase-null variant and a variant specifically impaired in targeting nucleosomal histones. Cells expressing either of these BRCA1-BARD1 separation-of-function alleles are hypersensitive to DNA-damaging agents. Furthermore, we demonstrate that BRCA1-BARD1 ligase is not only required for DNA resection during homology-directed repair (HDR) but also contributes to later stages for HDR completion. Altogether, our findings reveal crucial, previously unrecognized roles of BRCA1-BARD1 ligase activity in genome repair via HDR, settle prior controversies regarding BRCA1-BARD1 ligase functions, and catalyze new efforts to uncover substrates related to tumor suppression.
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•Provide insights into BRCA1-BARD1 ligase regulation and identify a truly inactive mutant•BRCA1-BARD1 E3 ligase activity is critical for DNA end resection•BRCA1-BARD1 E3 ligase contributes to later steps of homologous recombination•Histone ubiquitylation by BRCA1-BARD1 plays an important role in DNA end resection
Wang and Li et al. unveil the intricate regulatory mechanisms of BRCA1-BARD1 ubiquitylation, identify a truly ligase-null variant and another variant specifically impaired in targeting nucleosomal histones, and elucidate the pivotal roles of BRCA1-BARD1 ligase in not only early DNA end resection but also subsequent stages in homology-directed repair.
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