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espanolEl cancer de mama representa la principal causa de muerte por tumores malignos en mujeres. Se considera una entidad multifactorial, con una clara vinculacion con los factores hormonales y reproductivos de las pacientes. La presentacion clinica mas habitual es la existencia de una masa indolora a nivel local. Su diagnostico se basa en la triada de valoracion clinica, prueba de imagen y biopsia, destacando la mamografia como prueba esencial del cribado poblacional. Su pronostico se relaciona con el subtipo biologico y el estadio tumoral al diagnostico. Los objetivos y la modalidad de tratamiento varian en funcion del estadio tumoral. En el tratamiento de estadios precoces, el cual persigue una intencion curativa, ademas de los tratamientos locales con cirugia y radioterapia, destaca el sistemico adyuvante o neoadyuvante, con quimioterapia, hormonoterapia, tratamiento biologico y/o combinaciones de estos. En presencia de enfermedad metastasica, el objetivo del mismo es paliativo. En esta situacion, a las terapias clasicas con quimioterapia y hormonoterapia, se les ha asociado en los ultimos anos otras nuevas terapias. EnglishBreast cancer represents the main cause of death from malignant tumors in women. It is considered a multifactorial entity, linked to the hormonal and reproductive factors of the patients. The most common clinical presentation is the presence of a painless mass in the breast. The diagnosis is based on the triad of clinical assessment, imaging test and biopsy, highlighting mammography as an essential test in population screening. The prognosis depends on the biological subtype and the tumor stage at diagnosis. The objectives and the modality of treatment varies depending on the tumor stage. In the treatment of early stages, which has a curative intention, local treatment with surgery and radiotherapy is important, as well as adjuvant or neoadjuvant systemic treatment with chemotherapy, hormone therapy, biological treatment and/or combinations of them. In the presence of metastatic disease, the goal of treatment is palliative. In this situation, classic therapies with chemotherapy and hormonal therapy have been joined in recent years by the incorporation of new therapies.

espanolEn torno al 2% de los canceres de endometrio, el 7% de los canceres de mama y el 15% de los canceres de ovario son hereditarios. Identificar a estas pacientes resulta fundamental de cara a la prevencion del desarrollo de cancer en el futuro, en ellas y otros miembros de la familia, pero tambien para un apropiado tratamiento de la enfermedad. En base a la evidencia cientifica actual y a las recomendaciones de las guias de practica clinica, proponemos un algoritmo para facilitar el diagnostico de sospecha de cancer hereditario y la apropiada derivacion de dichas pacientes a unidades de consejo genetico (CG). EnglishAbout 2% of endometrial cancers, 7% of breast cancers and 15% of ovarian cancers are hereditary. In order to prevent cancer development and to set up the proper treatment, it is mandatory to identify those patients and their relatives. According with current scientific evidence and clinical practice guidelines, we propose an algorithm to facilitate the diagnosis of suspected inherited cancer and the appropriate referral of patients to hereditary cancer genetic counseling units (HCGCUs).

Coronary artery disease (CAD) is the most common cardiovascular disorder. Vascular surgery strategies for coronary revascularization (either percutaneous or open) show a high rate of failure because of restenosis of the vessel, due to phenotypic switch of vascular smooth muscle cells (VSMCs) leading to proliferation and migration. We have previously reported that the inhibition of Kv1.3 channel function with selective blockers represents an effective strategy for the prevention of restenosis in human vessels used for coronary angioplasty procedures. However, delivery systems for controlled release of these drugs have not been investigated. Here we tested the efficacy of several formulations of elastin like recombinamers (ELRs) hydrogels to deliver the Kv1.3 blocker PAP-1 in various restenosis models. The dose and time course of PAP-1 release from ELRs click hydrogels was able to inhibit human VSMC proliferation in vitro as well as remodeling of human vessels in organ culture and restenosis in in vivo models. We conclude that this combination of active compound and advanced delivery method could improve the outcomes of vascular surgery in patients., The authors are grateful for financial support from the European Social Fund (ESF) and the European Regional Development Fund (ERDF), as well as grants from the EU H2020-NMP-2014-646075), the Spanish Ministerio de Economia y Competitividad MINECO (grants BFU2016-75360-R, DTS19/00162, MAT2016-79435-R, MAT2016-78903-R and RTI2018-096320-B-C22), the Junta de Castilla y León (grants VA114P17 and VA317P18), the CIBER-BBN, the JCyL and the Instituto de Salud Carlos III under the “Network Center of Regenerative Medicine and Cellular Therapy of Castilla and Leon”. S. Moreno-Estar and S. Serrano are predoctoral fellows of the Junta de Castilla y León and M. Arévalo-Martínez is predoctoral fellow of UVa-Santander.

© 2020 Published by Elsevier Inc, The modulation of voltage-gated K+ (Kv) channels, involved in cell proliferation, arises as a potential therapeutic approach for the prevention of intimal hyperplasia present in in-stent restenosis (ISR) and allograft vasculopathy (AV). We studied the effect of PAP-1, a selective blocker of Kv1.3 channels, on development of intimal hyperplasia in vitro and in vivo in 2 porcine models of vascular injury. In vitro phenotypic modulation of VSMCs was associated to an increased functional expression of Kv1.3 channels, and only selective Kv1.3 channel blockers were able to inhibit porcine VSMC proliferation. The therapeutic potential of PAP-1 was then evaluated in vivo in swine models of ISR and AV. At 15-days follow-up, morphometric analysis demonstrated a substantial reduction of luminal stenosis in the allografts treated with PAP-1 (autograft 2.72 ± 1.79 vs allograft 10.32 ± 1.92 vs allograft + polymer 13.54 ± 8.59 vs allograft + polymer + PAP-1 3.06 ± 1.08 % of luminal stenosis; P = 0.006) in the swine model of femoral artery transplant. In the pig model of coronary ISR, using a prototype of PAP-1-eluting stent, no differences were observed regarding % of stenosis compared to control stents (31 ± 13 % vs 37 ± 18%, respectively; P = 0.372) at 28-days follow-up. PAP-1 treatment was safe and did not impair vascular healing in terms of delayed endothelialization, inflammation or thrombosis. However, an incomplete release of PAP-1 from stents was documented. We conclude that the use of selective Kv1.3 blockers represents a promising therapeutic approach for the prevention of intimal hyperplasia in AV, although further studies to improve their delivery method are needed to elucidate its potential in ISR., This work was supported by a Translational Research Project on Cardiology (2015) of the Sociedad Española de Cardiología and Fondo de Investigación Sanitario Instituto de Salud Carlos III (PI11/00225) to M. Roqué; BFU2016-75360-R from the Ministerio de Economía y Competitividad (MINECO) to M.T. Pérez-García and J.R. López-López; Junta de Castilla y León Grant VA114P17 to M.T. Pérez-García; and the CERCA Programme of the Generalitat de Catalunya.

Producción Científica, Objectives: Restenosis after vessel angioplasty due to dedifferentiation of the vascular smooth muscle cells (VSMCs) limits the success of surgical treatment of vascular occlusions. Type 2 diabetes (T2DM) has a major impact on restenosis, with patients exhibiting more aggressive forms of vascular disease and poorer outcomes after surgery. Kv1.3 channels are critical players in VSMC proliferation. Kv1.3 blockers inhibit VSMCs MEK/ERK signalling and prevent vessel restenosis. We hypothesize that dysregulation of microRNAs (miR) play critical roles in adverse remodelling, contributing to Kv1.3 blockers efficacy in T2DM VSMCs. Methods and results: We used clinically relevant in vivo models of vascular risk factors (VRF) and vessels and VSMCs from T2DM patients. Results: Human T2DM vessels showed increased remodelling, and changes persisted in culture, with augmented VSMCs migration and proliferation. Moreover, there were downregulation of PI3K/AKT/mTOR and upregulation of MEK/ERK pathways, with increased miR-126 expression. The inhibitory effects of Kv1.3 blockers on remodelling were significantly enhanced in T2DM VSMCs and in VRF model. Finally, miR-126 overexpression confered “diabetic” phenotype to non-T2DM VSMCs by downregulating PI3K/AKT axis. Conclusions: miR-126 plays crucial roles in T2DM VSMC metabolic memory through activation of MEK/ERK pathway, enhancing the efficacy of Kv1.3 blockers in the prevention of restenosis in T2DM patients., Ministerio de Economía, Industria y Competitividad (grant BFU2016-75360-R and SAF2016-77871-C2-1-R), Junta de Castilla y León (grants VA114P17; VA172P20 and CLU-2019-02), Novo Nordisk Foundation (grant 34366), Swedish Research Council (grants 2017–00860 and 2020-01145), Swedish Heart and Lung Foundation (grant 20200322)

espanolEl cancer de mama es uno de los tumores en los que antes y en mayor numero se ha incorporado la utilizacion de biomarcadores en la practica clinica. Diferenciamos entre marcadores pronosticos y predictivos de respuesta, aunque algunos de ellos pertenecen a ambos grupos. Desde los clasicos detectados por inmunohistoquimica (como son los receptores de estrogenos, progesterona, HER2 y Ki67) hasta los actuales en desarrollo basados principalmente en expresion genetica (BRCA, PI3K) y del sistema inmune (PD-L1, TILS), los biomarcadores son fundamentales para la clasificacion de la enfermedad y la eleccion de los tratamientos. Ademas, plataformas moleculares y de biopsia liquida estan en proceso de validacion clinica actualmente. EnglishBreast cancer is one of the tumor types in which the use of biomarkers has been earlier incorporated into clinical practice and in the greatest number. Biomarkers are classified into two groups: prognostic markers and predictive response markers, but some of them belong to both groups. Biomarkers, including immunohistochemistry markers (like estrogen, progesterone receptors, HER2 and Ki67) and current ones based mainly on gene (BRCA, PI3K) and immune system (PD-L1, TILS) expression, are essential in disease classification and treatment choice. Nowadays, molecular and liquid-biopsy platforms, are being validated.

The Transient Receptor Potential Melastatin 3 (TRPM3) is a Ca2+-permeable non-selective cation channel activated by the neurosteroid pregnenolone sulfate (PS). This compound was previously shown to contract mouse aorta by activating TRPM3 in vascular smooth muscle cells (VSMC), and proposed as therapeutic modulator of vascular functions. However, PS effects and the role of TRPM3 in resistance arteries remain unknown. Thus, we aimed at determining the localization and physiological role of TRPM3 in mouse mesenteric arteries. Real-time qPCR experiments, anatomical localization using immunofluorescence microscopy and patch-clamp recordings in isolated VSMC showed that TRPM3 expression in mesenteric arteries is restricted to perivascular nerves. Pressure myography experiments in wild type (WT) mouse arteries showed that PS vasodilates with a concentration-dependence that was best fit by two Hill components (effective concentrations, EC50, of 14 and 100 μM). The low EC50 component was absent in preparations from Trpm3 knockout (KO) mice and in WT arteries in the presence of the CGRP receptor antagonist BIBN 4096. TRPM3-dependent vasodilation was partially inhibited by a cocktail of K+ channel blockers, and not mediated by β-adrenergic signaling. We conclude that, contrary to what was found in aorta, PS dilates mesenteric arteries, partly via an activation of TRPM3 that triggers CGRP release from perivascular nerve endings and a subsequent activation of K+ channels in VSMC. We propose that TRPM3 is implicated in the regulation of the tone of resistance arteries and that its activation by yet unidentified endogenous damage-associated molecules lead to protective vasodilation responses in mesenteric arteries., This work was supported by grants from the Fund for Scientific Research Flanders (FWO, G.0C68.15, Belgium) to KT, the Ministerio de Economía y Competitividad (BFU2013-45867-R and BFU2016-75360-R, Spain) to JRLL and MTPG and Junta de Castilla y León(VA114P17, Spain) to MTPG. Y.A.A. is a Postdoctoral Fellow of the FWO (Belgium).

Artículo escrito por un elevado número de autores, solo se referencian el que aparece en primer lugar, el nombre del grupo de colaboración, si le hubiere, y los autores pertenecientes a la UAM, Background We explored the influence of BRAF and PIK3CA mutational status on the efficacy of bevacizumab or cetuximab plus 5-fluorouracil/leucovorin and irinotecan (FOLFIRI) as first-line therapy in patients with RAS wild-type metastatic colorectal cancer (mCRC). Patients and methods VISNÚ-2 was a multicentre, randomised, phase II study. Patients with RAS wild-type mCRC and 1), and allocated to bevacizumab (5 mg/kg every 2 weeks) or cetuximab (400 mg/m2 then 250 mg/m2 weekly) plus FOLFIRI [irinotecan 180 mg/m2, leucovorin 400 mg/m2, 5-fluorouracil 400 mg/m2 (bolus) then 2400 mg/m2 (46-h continuous infusion) every 2 weeks]. The primary endpoint was progression-free survival (PFS). All analyses were exploratory. Results Two hundred and forty patients with BRAF/PIK3CA wild-type (n = 196) or BRAF- and/or PIK3CA-mutated tumours (n = 44) were enrolled. Median PFS was 12.7 and 8.8 months in patients with BRAF/PIK3CA wild-type and BRAF/PIK3CA-mutated tumours, respectively [hazard ratio (HR) = 1.22; 95% confidence interval (CI) 0.80-1.85; P = 0.3602]. In the BRAF- and/or PIK3CA-mutated cohort, median PFS was 2.8, 8.8 and 15.0 months in patients with BRAF/PI3KCA-mutated (n = 8), BRAF-mutated/PI3KCA wild-type (n = 16) and BRAF wild-type/PI3KCA-mutated (n = 20) tumours, respectively (P = 0.0002). PFS was similar with bevacizumab plus FOLFIRI versus cetuximab plus FOLFIRI in BRAF/PIK3CA wild-type (HR = 0.99; 95% CI 0.67-1.45; P = 0.9486) and BRAF/PIK3CA-mutated tumours (HR = 1.11; 95% CI 0.53-2.35; P = 0.7820). The most common grade 3/4 treatment-related adverse events were neutropenia, diarrhoea and asthenia in both treatment groups. Conclusions BRAF/PIK3CA status influences outcomes in patients with RAS wild-type mCRC but does not appear to assist with the selection of first-line targeted therapy, This work was supported by Roche Farma S.A (no grant number). Medical writing support was funded by Roche Farma S.A and provided by H. Lamb and L. Miller of Miller Medical Communications Ltd.

© The Author(s) 2021., Exposure to Gram-negative bacterial LPS exacerbates host immune responses and may lead to sepsis, a life-threatening condition. Despite its high mortality and morbidity, no drugs specifically directed to treating sepsis are currently available. Using human cell genetic depletion, pharmacological inhibition, live-cell microscopy and organelle-targeted molecular sensors we present evidence that the channel TRPC3 is activated intracellularly during macrophage exposure to LPS and is essential for Ca2+ release from internal stores. In this manner, TRPC3 participates in cytosolic Ca2+ elevations, activation of the transcription factor NF-κB and cytokine upregulation. We also report that TRPC3 is activated by diacylglycerol generated by the phosphatidic acid phosphatase lipin-1. In accord with this, lipin-1-deficient cells exhibit reduced Ca2+ responses to LPS challenge. Finally, pharmacological inhibition of TRPC3 reduces systemic inflammation induced by LPS in mice. Collectively, our study unveils a central component of LPS-triggered Ca2+ signaling that involves intracellular sensing of lipin-1-derived DAG by TRPC3, and opens new opportunities for the development of strategies to treat LPS-driven inflammation., This work was supported by the Spanish Ministry of Economy, Industry, and Competitiveness (grant SAF2016-80883-R) and the Spanish Ministry of Science and Innovation (grants PID2019-105989RB-I00 and PID2020-118517RB-I00), and the Regional Government of Castile and Leon (grants CSI141P20 and VA172P20, co-financed by the European Union through the European Regional Development Fund). Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas (CIBERDEM) is an initiative of Instituto de Salud Carlos III.

Chronic kidney disease (CKD) significantly increases cardiovascular risk. In advanced CKD stages, accumulation of toxic circulating metabolites and mineral metabolism alterations triggers vascular calcification, characterized by vascular smooth muscle cell (VSMC) transdifferentiation and loss of the contractile phenotype. Phenotypic modulation of VSMC occurs with significant changes in gene expression. Even though ion channels are an integral component of VSMC function, the effects of uremia on ion channel remodeling has not been explored. We used an in vitro model of uremia-induced calcification of human aorta smooth muscle cells (HASMCs) to study the expression of 92 ion channel subunit genes. Uremic serum-induced extensive remodeling of ion channel expression consistent with loss of excitability but different from the one previously associated with transition from contractile to proliferative phenotypes. Among the ion channels tested, we found increased abundance and activity of voltage-dependent K+ channel Kv1.3. Enhanced Kv1.3 expression was also detected in aorta from a mouse model of CKD. Pharmacological inhibition or genetic ablation of Kv1.3 decreased the amount of calcium phosphate deposition induced by uremia, supporting an important role for this channel on uremia-induced VSMC calcification.

[Objective]: We have previously described that changes in the expression of Kv channels associate to phenotypic modulation (PM), so that Kv1.3/Kv1.5 ratio is a landmark of vascular smooth muscle cells phenotype. Moreover, we demonstrated that the Kv1.3 functional expression is relevant for PM in several types of vascular lesions. Here, we explore the efficacy of Kv1.3 inhibition for the prevention of remodeling in human vessels, and the mechanisms linking the switch in Kv1.3 /Kv1.5 ratio to PM., [Approach and Results]: Vascular remodeling was explored using organ culture and primary cultures of vascular smooth muscle cells obtained from human vessels. We studied the effects of Kv1.3 inhibition on serum-induced remodeling, as well as the impact of viral vector-mediated overexpression of Kv channels or myocardin knock-down. Kv1.3 blockade prevented remodeling by inhibiting proliferation, migration, and extracellular matrix secretion. PM activated Kv1.3 via downregulation of Kv1.5. Hence, both Kv1.3 blockers and Kv1.5 overexpression inhibited remodeling in a nonadditive fashion. Finally, myocardin knock-down induced vessel remodeling and Kv1.5 downregulation and myocardin overexpression increased Kv1.5, while Kv1.5 overexpression inhibited PM without changing myocardin expression., [Conclusions]: We demonstrate that Kv1.5 channel gene is a myocardin-regulated, vascular smooth muscle cells contractile marker. Kv1.5 downregulation upon PM leaves Kv1.3 as the dominant Kv1 channel expressed in dedifferentiated cells. We demonstrated that the inhibition of Kv1.3 channel function with selective blockers or by preventing Kv1.5 downregulation can represent an effective, novel strategy for the prevention of intimal hyperplasia and restenosis of the human vessels used for coronary angioplasty procedures., This work was supported by grant BFU2016-75360-R from the Ministerio de Economía y Competitividad (MINECO), to M.T. Pérez-García and J.R. López-López and Junta de Castilla y León Grant VA114P17 to M.T. Pérez-García. N. García-Mateo was supported by FIS PI15/00064 from the Instituto de Salud Carlos III. M. Arévalo-Martínez and J. Serna are predoctoral fellows of the UVa-Santander, and S. Moreno-Estar is a predoctoral fellow of the JCyL. K. Swärd was supported by the Swedish Research Council (2017-01225_3).

Key points Canonical transient receptor potential (TRPC)3 and TRPC6 channels of vascular smooth muscle cells (VSMCs) mediate stretch- or agonist-induced cationic fluxes, contributing to membrane potential and vascular tone. Native TRPC3/C6 channels can form homo- or heterotetrameric complexes, which can hinder individual TRPC channel properties. The possibility that the differences in their association pattern may change their contribution to vascular tone in hypertension is unexplored. Functional characterization of heterologously expressed channels showed that TRPC6-containing complexes exhibited Pyr3/Pyr10-sensitive currents, whereas TRPC3-mediated currents were blocked by anti-TRPC3 antibodies. VSMCs from hypertensive (blood pressure high; BPH) mice have larger cationic basal currents insensitive to Pyr10 and sensitive to anti-TRPC3 antibodies. Consistently, myography studies showed a larger Pyr3/10-induced vasodilatation in BPN (blood pressure normal) mesenteric arteries. We conclude that the increased TRPC3 channel expression in BPH VSMCs leads to changes in TRPC3/C6 heteromultimeric assembly, with a higher TRPC3 channel contribution favouring depolarization of hypertensive VSMCs. Abstract Increased vascular tone in essential hypertension involves a sustained rise in total peripheral resistance. A model has been proposed in which the combination of membrane depolarization and higher L-type Ca2+ channel activity generates augmented Ca2+ influx into vascular smooth muscle cells (VSMCs), contraction and vasoconstriction. The search for culprit ion channels responsible for membrane depolarization has provided several candidates, including members of the canonical transient receptor potential (TRPC) family. TRPC3 and TRPC6 are diacylglycerol-activated, non-selective cationic channels contributing to stretch- or agonist-induced depolarization. Conflicting information exists regarding changes in TRPC3/TRPC6 functional expression in hypertension. However, although TRPC3-TRPC6 channels can heteromultimerize, the possibility that differences in their association pattern may change their functional contribution to vascular tone is largely unexplored. We probe this hypothesis using a model of essential hypertension (BPH mice; blood pressure high) and its normotensive control (BPN mice; blood pressure normal). First, non-selective cationic currents through homo- and heterotetramers recorded from transfected Chinese hamster ovary cells indicated that TRPC currents were sensitive to the selective antagonist Pyr10 only when TRPC6 was present, whereas intracellular anti-TRPC3 antibody selectively blocked TRPC3-mediated currents. In mesenteric VSMCs, basal and agonist-induced currents were more sensitive to Pyr3 and Pyr10 in BPN cells. Consistently, myography studies showed a larger Pyr3/10-induced vasodilatation in BPN mesenteric arteries. mRNA and protein expression data supported changes in TRPC3 and TRPC6 proportions and assembly, with a higher TRPC3 channel contribution in BPH VSMCs that could favour cell depolarization. These differences in functional and pharmacological properties of TRPC3 and TRPC6 channels, depending on their assembly, could represent novel therapeutical opportunities.

Producción Científica, Patients with chronic kidney disease (CKD) have a markedly increased incidence of cardiovascular disease (CVD). The high concentration of circulating uremic toxins and alterations in mineral metabolism and hormone levels produce vascular wall remodeling and significant vascular damage. Medial calcification is an early vascular event in CKD patients and is associated to apoptosis or necrosis and trans-differentiation of vascular smooth muscle cells (VSMC) to an osteogenic phenotype. VSMC obtained from bovine or rat aorta and cultured in the presence of increased inorganic phosphate (Pi) have been extensively used to study these processes. In this study we used human aortic VSMC primary cultures to compare the effects of increased Pi to treatment with serum obtained from uremic patients. Uremic serum induced calcification, trans-differentiation and phenotypic remodeling even with normal Pi levels. In spite of similar calcification kinetics, there were fundamental differences in osteochondrogenic marker expression and alkaline phosphatase induction between Pi and uremic serum-treated cells. Moreover, high Pi induced a dramatic decrease in cell viability, while uremic serum preserved it. In summary, our data suggests that primary cultures of human VSMC treated with serum from uremic patients provides a more informative model for the study of vascular calcification secondary to CKD., Ministerio de Economía, Industria y Competitividad (grant BFU2016-78374-R, BFU2013-45867-R and BFU2016-75360-R), Instituto de Salud Carlos III (grant PI13/01726)

[Purpose]: Breakthrough cancer pain (BTcP) has been shown to be a prevalent and poor prognostic factor for oncologic patients, which remain under diagnosed and undertreated. In 2012, the Spanish Society of Medical Oncology (SEOM) published a clinical practice guideline (CPG) for the treatment of cancer pain which specifically addressed the management of BTcP., [Methods]: Fundación ECO designed a qualitative study using an Internet-based survey to investigate the attitudes toward, compliance with, and use of SEOM Guideline., [Results]: A total of 83 oncologists with a mean experience of 13 years responded. Overall, 82% were aware of different guidelines to manage BTcP. Notably, attitudes toward guidelines were highly positive and there was nearly unanimous agreement that CPG provided the best scientific evidence available (99%), on the minimum information to be gathered for the medical history (100%), on the need for a specific treatment for BTcP (100%), and fentanyl as the first-choice drug (99%). Interestingly, there were discrepancies between what oncologists agreed with and what they do in clinical practice. In fact, 87.6% declare full compliance with SEOM guideline, although adherence to registration of BTcP data in medical records ranged from 30.1 to 91.6% (mean 64.5%); therapeutic management compliance was higher ranging from 75.9 to 91.6%. Main barriers identified were time pressure together with vague statements and limited dissemination of the guidelines., [Conclusion]: Despite oncologist’s clinical practice is increasingly guided by GPC, it suffers from limited compliance, at least in part due to suboptimal statements. Improved dissemination and education are needed to enhance guideline implementation., This study was funded by Kyowa Kirin Farmacéutica S. L.U. through Fundación ECO.

Producción Científica, K+ channels encoded by the ether-a-go-go related gene (ERG1 or KCNH2) are important determinants of the cardiac action potential. Expression of both cardiac isoforms (ERG1a and ERG1b) were identified in murine portal vein and distinctive voltage-gated K+ currents were recorded from single myocytes. The aim of the present study was to ascertain the expression and functional impact of ERG channels in murine arteries., British Heart Foundation (projects PG/06/057/20864 and PG/11/93/21943), Medical Research Council (project MR/K019074/1), Ministerio de Economía, Industria y Competitividad (grants BFU2013-45867-R and BFU2016-75360)

The economic situation showed that the resources devoted to health spending are limited, making rationalisation of their consumption necessary. The relevance of pharmacoeconomic analyses is becoming crucial. The ECO Foundation, promoting the quality of oncology care, set out to analyse the consensus on the new therapeutic targets inclusion and the integration of pharmacoeconomics when evaluating their effectiveness. Study about pharmacoeconomic estimations was performed during the first ECO-Seminar (2010). It was developed using a modified Delphi method, in four stages: (1) committee coordinator establishment, (2) expert-panel selection, (3) preparation and submission of survey (1 question) by email, and (4) analysis of the degree of consensus reached. Results were obtained from surveys completed by 35 experts. Regarding the tolerable annual cost for the approval of new drugs, 68.8 % of the respondents considered a cost per quality-adjusted life year (QALY) gained between €30,000 and 100,000 acceptable (34.4 % €30,000–60,000; 34.4 % €60,000–100,000), 21.9 % of the respondents found costs between €100,000–150,000/QALY and 9.3 % of the respondents found costs above €150,000/QALY acceptable. The costs of new drugs are higher than traditional treatments, making it a priority to identify subgroups of patients with specific molecular profiles as candidates for higher-efficiency-targeted therapies. The allocation of the available resources to the most effective interventions, to achieve the best clinical outcomes with lower costs and best subjective profile possible, allows expenditure to be rationalised. Pharmacoeconomic studies are a basic tool for obtaining better health outcomes according to the available resources, while also considering the other needs of the population.

Cinnamaldehyde (CA), a major component of cinnamon, is known to have important actions in the cardiovascular system, including vasorelaxation and decrease in blood pressure. Although CA-induced activation of the chemosensory cation channel TRPA1 seems to be involved in these phenomena, it has been shown that genetic ablation of Trpa1 is insufficient to abolish CA effects. Here, we confirm that CA relaxes rat aortic rings and report that it has negative inotropic and chronotropic effects on isolated mouse hearts. Considering the major role of L-type Ca(2+) channels in the control of the vascular tone and cardiac contraction, we used whole-cell patch-clamp to test whether CA affects L-type Ca(2+) currents in mouse ventricular cardiomyocytes (VCM, with Ca(2+) as charge carrier) and in mesenteric artery smooth muscle cells (VSMC, with Ba(2+) as charge carrier). We found that CA inhibited L-type currents in both cell types in a concentration-dependent manner, with little voltage-dependent effects. However, CA was more potent in VCM than in VSMC and caused opposite effects on the rate of inactivation. We found these divergences to be at least in part due to the use of different charge carriers. We conclude that CA inhibits L-type Ca(2+) channels and that this effect may contribute to its vasorelaxing action. Importantly, our results demonstrate that TRPA1 is not a specific target of CA and indicate that the inhibition of voltage-gated Ca(2+) channels should be taken into account when using CA to probe the pathophysiological roles of TRPA1.

Supported by Ministerio de Sanidad, ISCIII grant R006/009 (Red Heracles), Ministerio de Ciencia e Innovacion grant BFU2010-15898 (MTPG) and Junta de Castilla y Leon grant VA094A11-2 (JRLL). ST is a fellow of the Spanish MICINN. Work in Dr. L. Fernando Santana’s laboratory was supported by NIH grants HL085870 and P01HL095488.

The increased vascular tone that defines essential hypertension is associated with depolarization of vascular smooth muscle cells (VSMCs) and involves a change in the expression profile of ion channels promoting arterial contraction. As a major regulator of VSMC resting membrane potential (VM), K+ channel activity is an important determinant of vascular tone and vessel diameter. However, hypertension-associated changes in the expression and/or modulation of K+ channels are poorly defined, due to their large molecular diversity and their bed-specific pattern of expression. Moreover, the impact of these changes on the integrated vessel function and their contribution to the development of altered vascular tone under physiological conditions need to be confirmed. Hypertensive (BPH) and normotensive (BPN) mice strains obtained by phenotypic selection were used to explore whether changes in the functional expression of VSMC inward rectifier K+ channels contribute to the more depolarized resting VM and the increased vascular reactivity of hypertensive arteries. We determined the expression levels of inward rectifier K+ channel mRNA in several vascular beds from BPN and BPH animals, and their functional contribution to VSMC excitability and vascular tone in mesenteric arteries. We found a decrease in the expression of Kir2.1, Kir4.1, Kir6.x and SUR2 mRNA in BPH VSMCs, and a decreased functional contribution of both KIR and KATP channels in isolated BPH VSMCs. However, only the effect of KATP channel modulators was impaired when exploring vascular tone, suggesting that decreased functional expression of KATP channels may be an important element in the remodelling of VSMCs in essential hypertension.

Essential hypertension involves a gradual and sustained increase in total peripheral resistance, reflecting an increased vascular tone. This change associates with a depolarization of vascular myocytes, and relies on a change in the expression profile of voltage-dependent ion channels (mainly Ca2+ and K+ channels) that promotes arterial contraction. However, changes in expression and/or modulation of voltage-dependent K+ channels (Kv channels) are poorly defined, due to their large molecular diversity and their vascular bed-specific expression. Here we endeavor to characterize the molecular and functional expression of Kv channels in vascular smooth muscle cells (VSMCs) and their regulation in essential hypertension, by using VSMCs from resistance (mesenteric) or conduit (aortic) arteries obtained from a hypertensive inbred mice strain, BPH, and the corresponding normotensive strain, BPN. Real-time PCR reveals a differential distribution of Kv channel subunits in the different vascular beds as well as arterial bed-specific changes under hypertension. In mesenteric arteries, the most conspicuous change was the de novo expression of Kv6.3 (Kcng3) mRNA in hypertensive animals. The functional relevance of this change was studied by using patch-clamp techniques. VSMCs from BPH arteries were more depolarized than BPN ones, and showed significantly larger capacitance values. Moreover, Kv current density in BPH VSMCs is decreased mainly due to the diminished contribution of the Kv2 component. The kinetic and pharmacological profile of Kv2 currents suggests that the expression of Kv6.3 could contribute to the natural development of hypertension.

Objetivos El estudio del CO 2 espirado mediante capnografia (Pet-CO 2 ) proporciona un parametro no invasivo del metabolismo sistemico, la perfusion y la circulacion. Existen estudios que relacionan PetCO 2 con el estado metabolico de pacientes pediatricos con cetoacidosis diabetica. La gastroenteritis aguda es causa de acidosis metabolica, por lo que la capnografia podria ser util en estas situaciones. El objetivo fue determinar la relacion entre el PetCO 2 y el bicarbonato (HCO3) en plasma en ninos con gastroenteritis y acidosis. Material y metodos Estudio prospectivo desde abril de 2006 hasta enero de 2007 con ninos con deshidratacion secundaria a gastroenteritis y que presentaban en la analitica un pH inferior o igual a 7,30 y un HCO3 inferior a 20 mEq/l. Se excluyeron ninos con mala tolerancia del capnografo y con patologia pulmonar de base. Las variables recogidas fueron PetCO 2 y HCO3 basal y a la hora del inicio de fluidoterapia intravenosa, datos epidemiologicos, clinicos, bioquimicos y necesidad de hospitalizacion. Resultados La muestra fue de 25 pacientes (10 ninas y 15 ninos) con una edad media de 11,6 + 10 meses (1-144 meses). Se encontro asociacion estadisticamente significativa entre PetCO 2 y bicarbonato tanto basal como a la hora de la fluidoterapia intravenosa y se obtuvo un coeficiente de correlacion de Pearson r = 0,61 y r = 0,75, respectivamente. Conclusiones La capnografia es un metodo no invasivo util para estimar el estado metabolico de pacientes pediatricos con gastroenteritis y deshidratacion.

The chick retina has four morphological cone types that differ not only in shape, but also in the visual pigment in the outer segment, in the colour of the oil droplet in the inner segment and in synaptic connectivity. Neither the type of droplet nor the visual pigment has been definitively established for the four cone types. The main aim of the present work has been the isolation of entire live photoreceptors in order to study the oil droplet colour in each cone type and to quantify each type. We have improved an earlier retinal cell isolation method and obtained large numbers of entire cones. Principal cones (27% of the cones) possess a yellow or colourless droplet. Accessory cones (27% of the cones) all contain a small pale green droplet. Straight cones (44% of the cones) have a red, orange, yellow, or colourless droplet. Oblique cones (1.66% of the cones) all have a colourless droplet. We have found that straight cones with a red, orange, or yellow droplet differ in terms of the position of the nucleus and their percentage and conclude that they are distributed in three rows in the outer nuclear layer (ONL) of the central retina. Our study of 4,6-diamidino-2-phenylindole-stained retinal sections has revealed three rows of nuclei instead of the two currently thought to form the ONL. Together, our results show a larger cone diversity than previously known, suggest a larger functional diversity and provide an efficient method for isolating entire chick photoreceptors.

In 2002, a group of researchers in the fields of cell electrophysiology, cardiology, population genetics, epidemiology, proteomics, molecular biology, bioinformatics and statistics decided to take up the challenge of investigating the mechanisms and genetics of arterial hypertension (AH). Mechanisms related to ion channel regulation of arterial smooth muscle function were identified. The HERACLES (Hipertension Esencial: Red de Analisis de Canales ionicos de la musculatura Lisa arterial y su Explotacion terapeutica Sistematica) network was honored with a distinguished mention in the 2005 evaluation, and was strengthened by the incorporation of new research groups in 2007. The work of the HERACLES network is characterized as much by the transfer of knowledge «from bedside to bench» as by its converse: «from bench to bedside». The current objectives of the HERACLES network are: a) to study the Ca2+-dependent K+channels, the transient receptor potential (TRP) cation channels, and the Ca2+-dependent Cl- channels that are involved in vascular physiology; b) to study protein expression maps in plasma and cardiovascular tissue and their significance for drug treatment; c) to study the effect of flavonoids on ion transport and responses to oxidative stress, and d) to identify biomarkers of risk, prognosis, and treatment responses in extreme AH phenotypes. Our project includes a number of lines of research coordinated within cross-sectional programs based on centralized facilities, which are used by them. The HERACLES network has published more than 60 articles (available from: http://www.redheracles.net), funding has been received for more than 90 projects in competitive submissions to Spanish and six international bodies, and there is a DNA Biobank.

Producción Científica, Despite the substantial knowledge on the antidiabetic, antiobesity and antihypertensive actions of tungstate, information on its primary target/s is scarce. Tungstate activates both the ERK1/2 pathway and the vascular voltage- and Ca2+-dependent large-conductance BKαβ1 potassium channel, which modulates vascular smooth muscle cell (VSMC) proliferation and function, respectively. Here, we have assessed the possible involvement of BKαβ1 channels in the tungstate-induced ERK phosphorylation and its relevance for VSMC proliferation. Western blot analysis in HEK cell lines showed that expression of vascular BKαβ1 channels potentiates the tungstate-induced ERK1/2 phosphorylation in a Gi/o protein-dependent manner. Tungstate activated BKαβ1 channels upstream of G proteins as channel activation was not altered by the inhibition of G proteins with GDPβS or pertussis toxin. Moreover, analysis of Gi/o protein activation measuring the FRET among heterologously expressed Gi protein subunits suggested that tungstate-targeting of BKαβ1 channels promotes G protein activation. Single channel recordings on VSMCs from wild-type and β1-knockout mice indicated that the presence of the regulatory β1 subunit was essential for the tungstate-mediated activation of BK channels in VSMCs. Moreover, the specific BK channel blocker iberiotoxin lowered tungstate-induced ERK phosphorylation by 55% and partially reverted (by 51%) the tungstate-produced reduction of platelet-derived growth factor (PDGF)-induced proliferation in human VSMCs. Our observations indicate that tungstate-targeting of BKαβ1 channels promotes activation of PTX-sensitive Gi proteins to enhance the tungstate-induced phosphorylation of ERK, and inhibits PDGF-stimulated cell proliferation in human vascular smooth muscle., Ministerio de Economía, Industria y Competitividad (SAF2012-31089 to JMFF, SAF2012-38140 to MAV, BFU2013-45867-R to JRLL), Ministerio de Ciencia e Innovación (BFU 2008-00769 to JG, BFU2010-15898 to MTPG), Instituto de Salud Carlos III (RIC RD12/0042/0006, RD12/0042/0014, Red HERACLES), Junta de Castilla y León (VA094A11-2 to JRLL)

Phenotypic modulation (PM) of vascular smooth muscle cells (VSMCs) is central to the process of intimal hyperplasia which constitutes a common pathological lesion in occlusive vascular diseases. Changes in the functional expression of Kv1.5 and Kv1.3 currents upon PM in mice VSMCs have been found to contribute to cell migration and proliferation. Using human VSMCs from vessels in which unwanted remodeling is a relevant clinical complication, we explored the contribution of the Kv1.5 to Kv1.3 switch to PM. Changes in the expression and the functional contribution of Kv1.3 and Kv1.5 channels were studied in contractile and proliferating VSMCs obtained from human donors. Both a Kv1.5 to Kv1.3 switch upon PM and an anti-proliferative effect of Kv1.3 blockers on PDGF-induced proliferation were observed in all vascular beds studied. When investigating the signaling pathways modulated by the blockade of Kv1.3 channels, we found that anti-proliferative effects of Kv1.3 blockers on human coronary artery VSMCs were occluded by selective inhibition of MEK/ERK and PLCγ signaling pathways, but were unaffected upon blockade of PI3K/mTOR pathway. The temporal course of the anti-proliferative effects of Kv1.3 blockers indicates that they have a role in the late signaling events essential for the mitogenic response to growth factors. These findings establish the involvement of Kv1.3 channels in the PM of human VSMCs. Moreover, as current therapies to prevent restenosis rely on mTOR blockers, our results provide the basis for the development of novel, more specific therapies., Supported by grants from the Ministerio de Economía y Competitividad, Instituto de Salud Carlos III (RIC RD12/0042/0006, Red Heracles), Ministerio de Ciencia e Innovación (BFU2010-15898 to MTPG), Junta de Castilla y León (VA094A11-2 to, JRLL), and Fondo de Investigaciones Sanitarias (FIS PI11/00225 to MR)

The carotid body (CB) chemoreceptors participate in the ventilatory responses to acute and chronic hypoxia (CH). Arterial hypoxaemia increases breathing within seconds, and CB chemoreceptors are the principal contributors to this reflex hyperventilatory response. Acute hypoxia induces depolarization of CB chemoreceptors by inhibiting certain K+ channels, but the role of these channels in CH, as in high-altitude acclimatization, is less known. Here we explored the effects of prolonged (24–48 h) hypoxic exposure of rabbit CB chemoreceptor cells in primary cultures on the voltage-dependent K+ currents and on their response to acute hypoxia. We found that CH induces a decrease in the amplitude of outward K+ currents due to a reduction in a fast-inactivating BDS- and highly TEA-sensitive component of the current. In spite of this effect, acute hypoxic inhibition of K+ currents is increased in CH cultures, as well as hypoxia-induced depolarization. These data suggest that downregulation of this component (that does not contribute to the oxygen-sensitive K+ current (IKO2)) participates in the hypoxic sensitization. Pharmacological, immunocytochemical and quantitative PCR (qPCR) experiments demonstrate that CH-induced decrease in outward K+ currents is due to a downregulation of the expression of Kv3.4 channels. Taken together, our results suggest that CH sensitization in rabbit CB could be achieved by an increase in the relative contribution of IKO2 to the outward K+ current as a consequence of the decreased expression of the oxygen-insensitive component of the current. We conclude that acute and chronic hypoxia can exert their effects acting on different molecular targets.

The carotid body (CB) is an arterial chemoreceptor, bearing specialized type I cells that respond to hypoxia by closing specific K+ channels and releasing neurotransmitters to activate sensory axons. Despite having detailed information on the electrical and neurochemical changes triggered by hypoxia in CB, the knowledge of the molecular components involved in the signalling cascade of the hypoxic response is fragmentary. This study analyses the mouse CB transcriptional changes in response to low PO2 by hybridization to oligonucleotide microarrays. The transcripts were obtained from whole CBs after mice were exposed to either normoxia (21% O2), or physiological hypoxia (10% O2) for 24 h. The CB transcriptional profiles obtained under these environmental conditions were subtracted from the profile of control non-chemoreceptor adrenal medulla extracted from the same animals. Given the common developmental origin of these two organs, they share many properties but differ specifically in their response to O2. Our analysis revealed 751 probe sets regulated specifically in CB under hypoxia (388 up-regulated and 363 down-regulated). These results were corroborated by assessing the transcriptional changes of selected genes under physiological hypoxia with quantitative RT-PCR. Our microarray experiments revealed a number of CB-expressed genes (e.g. TH, ferritin and triosephosphate isomerase) that were known to change their expression under hypoxia. However, we also found novel genes that consistently changed their expression under physiological hypoxia. Among them, a group of ion channels show specific regulation in CB: the potassium channels Kir6.1 and Kcnn4 are up-regulated, while the modulatory subunit Kcnab1 is down-regulated by low PO2 levels.

As there are wide interspecies variations in the molecular nature of the O2-sensitive Kv channels in arterial chemoreceptors, we have characterized the expression of these channels and their hypoxic sensitivity in the mouse carotid body (CB). CB chemoreceptor cells were obtained from a transgenic mouse expressing green fluorescent protein (GFP) under the control of tyrosine hydroxylase (TH) promoter. Immunocytochemical identification of TH in CB cell cultures reveals a good match with GFP-positive cells. Furthermore, these cells show an increase in [Ca2+]i in response to low PO2, demonstrating their ability to engender a physiological response. Whole-cell experiments demonstrated slow-inactivating K+ currents with activation threshold around −30 mV and a bi-exponential kinetic of deactivation (τ of 6.24 ± 0.52 and 32.85 ± 4.14 ms). TEA sensitivity of the currents identified also two different components (IC50 of 17.8 ± 2.8 and 940.0 ± 14.7 μm). Current amplitude decreased reversibly in response to hypoxia, which selectively affected the fast deactivating component. Hypoxic inhibition was also abolished in the presence of low (10–50 μm) concentrations of TEA, suggesting that O2 interacts with the component of the current most sensitive to TEA. The kinetic and pharmacological profile of the currents suggested the presence of Kv2 and Kv3 channels as their molecular correlates, and we have identified several members of these two subfamilies by single-cell PCR and immunocytochemistry. This report represents the first functional and molecular characterization of Kv channels in mouse CB chemoreceptor cells, and strongly suggests that O2-sensitive Kv channels in this preparation belong to the Kv3 subfamily.

Hypoxia increases the release of neurotransmitters from chemoreceptor cells of the carotid body (CB) and the activity in the carotid sinus nerve (CSN) sensory fibers, elevating ventilatory drive. According to previous reports, perinatal hyperoxia causes CSN hypotrophy and varied diminishment of CB function and the hypoxic ventilatory response. The present study aimed to characterize the presumptive hyperoxic damage. Hyperoxic rats were born and reared for 28 days in 55%–60% O2; subsequent growth (to 3.5–4.5 months) was in a normal atmosphere. Hyperoxic and control rats (born and reared in a normal atmosphere) responded with a similar increase in ventilatory frequency to hypoxia and hypercapnia. In comparison with the controls, hyperoxic CBs showed (1) half the size, but comparable percentage area positive to tyrosine hydroxylase (chemoreceptor cells) in histological sections; (2) a twofold increase in dopamine (DA) concentration, but a 50% reduction in DA synthesis rate; (3) a 75% reduction in hypoxia-evoked DA release, but normal high [K+]0-evoked release; (4) a 75% reduction in the number of hypoxia-sensitive CSN fibers (although responding units displayed a nearly normal hypoxic response); and (5) a smaller percentage of chemoreceptor cells that increased [Ca2+]1 in hypoxia, although responses were within the normal range. We conclude that perinatal hyperoxia causes atrophy of the CB–CSN complex, resulting in a smaller number of chemoreceptor cells and fibers. Additionally, hyperoxia damages O2-sensing, but not exocytotic, machinery in most surviving chemoreceptor cells. Although hyperoxic CBs contain substantially smaller numbers of chemoreceptor cells/sensory fibers responsive to hypoxia they appear sufficient to evoke normal increases in ventilatory frequency.

Rabbit carotid body (CB) chemoreceptor cells possess a fast-inactivating K+ current that is specifically inhibited by hypoxia. We have studied the expression of Kvα subunits, which might be responsible for this current. RT-PCR experiments identified the expression of Kv1.4, Kv3.4, Kv4.1 and Kv4.3 mRNAs in the rabbit CB. There was no expression of Kv3.3 or Kv4.2 transcripts. Immunocytochemistry with antibodies to tyrosine hydroxylase (anti-TH) and to specific Kv subunits revealed the expression of Kv3.4 and Kv4.3 in chemoreceptor cells, while Kv1.4 was only found in nerve fibres. Kv4.1 mRNA was also found in chemoreceptor cells following in situ hybridization combined with anti-TH antibody labelling. Kv4.1 and Kv4.3 appeared to be present in all chemoreceptor cells, but Kv3.4 was only expressed in a population of them. Electrophysiological experiments applying specific toxins or antibodies demonstrated that both Kv3.4 and Kv4.3 participate in the oxygen-sensitive K+ current of chemoreceptor cells. However, toxin application experiments confirmed a larger contribution of members of the Kv4 subfamily. [Ca2+]i measurements under hypoxic conditions and immunocytochemistry experiments in dispersed CB cells demonstrated the expression of Kv3.4 and Kv4.3 in oxygen-sensitive cells; the presence of Kv3.4 in the chemoreceptor cell membrane was not required for the response to low PO2. In summary, three Kv subunits (Kv3.4, Kv4.1 and Kv4.3) may be involved in the fast-inactivating outward K+ current of rabbit CB chemoreceptor cells. The homogeneous distribution of the Kv4 subunits in chemoreceptor cells, along with their electrophysiological properties, suggest that Kv4.1, Kv4.3, or their heteromultimers, are the molecular correlate of the oxygen-sensitive K+ channel.

Producción Científica, K+ channels are central to vascular pathophysiology. Previous results demonstrated that phenotypic modulation associates with a change in Kv1.3 to Kv1.5 expression, and that Kv1.3 blockade inhibits proliferation of VSMCs cultures. Purpose: To explore whether the Kv1.3 to Kv1.5 switch could be a marker of the increased risk of intimal hyperplasia in essential hypertension and whether systemic treatment with Kv1.3 blockers can prevent intimal hyperplasia after endoluminal lesion . Methods: Morphometric and immunohistochemical analysis were performed in arterial segments following arterial injury and constant infusion of the Kv1.3 blocker PAP-1 during 28 days. Differential expression of K+ channel genes was studied in VSMC from hypertensive (BPH) and normotensive (BPN) mice, both in control and after endoluminal lesion. Finally, the migration and proliferation rate of BPN and BPH VSMCs was explored in vitro. Results: Changes in mRNA expression led to an increased Kv1.3/Kv1.5 ratio in BPH VSMC. Consistent with this, arterial injury in BPH mice induced a higher degree of luminal stenosis, (84±4 % vs. 70±5 % in BPN, p, La versión original del artículo contiene un error. El gráfico de la página 505 es incorrecto. La corrección del mismo se encuentra en el segundo fichero "Erratum to: K+ Channels Expression in Hypertension After Arterial Injury, and Effect of Selective Kv1.3 Blockade with PAP-1 on Intimal Hyperplasia Formation"., Ministerio de Economía, Industria y Competitividad (project RD12/0042/0006), Fondo de Investigación en Salud - Instituto Carlos III (project PI11/00225), VALTEC 09-1-0042, Ministerio de Ciencia, Innovación y Universidades (grant BFU2010-15898), Junta de Castilla y León (grant VA094A11-2)

Producción Científica, Hypoxic inhibition of large-conductance Ca2+-dependent K+ channels (maxiK) of rat carotid body type I cells is a well-established fact. However, the molecular mechanisms of such inhibition and the role of these channels in the process of hypoxic transduction remain unclear. We have examined the mechanisms of interaction of O2 with maxiK channels exploring the effect of hypoxia on maxiK currents recorded with the whole-cell and the inside-out configuration of the patch-clamp technique. Hypoxia inhibits channel activity both in whole-cell and in excised membrane patches. This effect is strongly voltage- and Ca2+-dependent, being maximal at low [Ca2+] and low membrane potential. The analysis of single-channel kinetics reveals a gating scheme comprising three open and five closed states. Hypoxia inhibits channel activity increasing the time the channel spends in the longest closed states, an effect that could be explained by a decrease in the Ca2+ sensitivity of those closed states. Reducing maxiK channels with dithiothreitol (DTT) increases channel open probability, whereas oxidizing the channels with 2,2′-dithiopyridine (DTDP) has the opposite effect. These results suggest that hypoxic inhibition is not related with a reduction of channel thiol groups. However, CO, a competitive inhibitor of O2 binding to hemoproteins, fully reverts hypoxic inhibition, both at the whole-cell and the single-channel level. We conclude that O2 interaction with maxiK channels does not require cytoplasmic mediators. Such interaction could be mediated by a membrane hemoprotein that, as an O2 sensor, would modulate channel activity., Dirección General de Investigación Científica y Técnica (grant PB97/0400)

Introduccion La disminucion en la produccion de hemo es probablemente la causa principal de la anemia observada en pacientes intoxicados por plomo, si bien la hemolisis provocada por los efectos sobre la membrana o por inhibicion de otras enzimas tales como la 5'-pirimidin nucleotidasa tambien pueden tener una importancia capital. La mayor fuente de exposicion al plomo proviene de su utilizacion en actividades industriales; sin embargo, fuera del ambito laboral el origen alimentario es la principal causa de contacto con este toxico. Material y metodos Presentamos las caracteristicas clinicas y analiticas de 12 casos de saturnismo de origen alimentario producidos en los ultimos 14 anos en 2 areas sanitarias del norte de Extremadura. Resultados La fuente de exposicion fue vino, vinagre y aceitunas en un caso, aguardiente artesanal en 5, en 2 pacientes fue por el consumo de agua canalizada por tuberias de plomo y en 2 no se determino la causa. El cuadro clinico fue superponible en todos, excepto en 1 paciente con encefalopatia y fallo hepatico. La anemia regenerativa con punteado basofilo sugirio el diagnostico. Todos recibieron tratamiento con acido etilendiaminotetracetico (EDTA) calcico disodico oral. Conclusiones La intoxicacion por plomo en zonas no industriales constituye una rareza; sin embargo, debido al uso de procedimientos artesanales en la elaboracion del vino y sus derivados nuevamente se esta incrementando. En un paciente con sintomas de saturnismo y con anemia regrenerativa debe revisarse la extension de sangre periferica.

Resumen El manejo de los tumores del estroma gastrointestinal, definidos como neoplasias mesenquimales c-Kit positivas, ha cambiado rapidamente en los ultimos cinco anos. El mesilato de imatinib (Glivec ® ) es el tratamiento estandar de los tumores del estroma gastrointestinal irresecables o metastaticos. El imatinib debe administrarse hasta el desarrollo de intolerancia o la progresion de la enfermedad. No es infrecuente que los tumores del estroma gastrointestinal aumenten de tamano durante los primeros meses de tratamiento, de ahi el valor limitado de los criterios convencionales de evaluacion de respuesta de los tumores solidos para determinar la eficacia del imatinib durante este periodo. La tomografia de emision de positrones empleando 18 F-fluorodesoxiglucosa ha demostrado tener una alta sensibilidad en la evaluacion precoz de la respuesta tumoral al imatinib. Presentamos el caso de una mujer de 53 anos diagnosticada de recidiva de tumor del estroma gastrointestinal 18 meses despues de finalizar tratamiento adyuvante con imatinib. Tras 72 horas de tratamiento con imatinib el tumor mostraba en la tomografia de emision de positrones una disminucion en la captacion de 18 F-fluorode-soxiglucosa.

Hypoxia activates erythropoietin-producing cells, chemoreceptor cells of the carotid body and pulmonary artery smooth muscle cells (PSMC) with a comparable arterial PO2 threshold of some 70 mmHg. The inhibition by CO of the hypoxic responses in the two former cell types has led to the proposal that a haemoprotein is involved in the detection of the PO2 levels. Here, we report the effect of CO on the hypoxic pulmonary vasoconstriction (HPV). Pulmonary arterial pressure (PAP) was measured in an in situ, blood-perfused lung preparation. PAP in normoxia (20% O2, 5% CO2) was 15.2+/-1.8 mmHg, and hypoxia (2% O2, 5% CO2) produced a DeltaPAP of 6.3+/-0.4 mmHg. Addition of 8% or 15% CO to the hypoxic gas mixture reduced the DeltaPAP by 88.3+/-2.7% and 78.2+/-6.1% respectively. The same levels of CO did not affect normoxic PAP nor reduced the DeltaPAP produced by angiotensin II. The effect of CO was studied after inhibition of the NO-cyclic guanosine monophosphate (cGMP) cascade with N-methyl-l-arginine (5.10(-5) M) or methylene blue (1.4.10(-4) M). It was found that both inhibitors more than doubled the hypoxic DeltaPAP without altering the effectiveness of CO to inhibit the HPV. In in vitro experiments we verified the inhibition of guanylate cyclase by measuring the levels of cGMP in segments of the pulmonary artery. Cyclic GMP levels were 1.4+/-0.2 (normoxia), 2.5+/-0.3 (hypoxia) and 3.3+/-0.5 pmole/mg tissue (hypoxia plus 8% CO); sodium nitroprusside increased normoxic cGMP levels about fourfold. Methylene blue reduced cGMP levels to less than 10% in all cases, and abolished the differences among normoxic, hypoxic and hypoxic plus CO groups. It is concluded that CO inhibits HPV by a NO-cGMP independent mechanism and it is proposed that a haemoprotein could be involved in O2-sensing in PSMC.

This work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 Unported License.-- et al., Gram-negative bacterial infections are accompanied by inflammation and somatic or visceral pain. These symptoms are generally attributed to sensitization of nociceptors by inflammatory mediators released by immune cells. Nociceptor sensitization during inflammation occurs through activation of the Toll-like receptor 4 (TLR4) signalling pathway by lipopolysaccharide (LPS), a toxic by-product of bacterial lysis. Here we show that LPS exerts fast, membrane delimited, excitatory actions via TRPA1, a transient receptor potential cation channel that is critical for transducing environmental irritant stimuli into nociceptor activity. Moreover, we find that pain and acute vascular reactions, including neurogenic inflammation (CGRP release) caused by LPS are primarily dependent on TRPA1 channel activation in nociceptive sensory neurons, and develop independently of TLR4 activation. The identification of TRPA1 as a molecular determinant of direct LPS effects on nociceptors offers new insights into the pathogenesis of pain and neurovascular responses during bacterial infections and opens novel avenues for their treatment. © 2014 Macmillan Publishers Limited. All rights reserved., O.F. and C.F.P. were predoctoral students of the Generalitat Valenciana. S.T., B.D., V.M. and J.A.M. were supported by predoctoral fellowships from the Spanish MINECO. Research was supported by Spanish public funds projects SAF2010-14990 and PROMETEO2010-046 to F.V., BFU2007-61524 to J.R.L.L., BFU2010-15898 to M.T.P.G., Instituto de Salud Carlos III PI12/00586 to R.S., BFU2005-08741 and CONSOLIDER-INGENIO 2010 CSD2007-00023 to C.B., ISCIII grants R006/009 (Red Heracles), the Spanish Fundación Marcelino Botín and Belgian Federal Government (IUAP P6/28 and P7/13), the Research Foundation-Flanders (F.W.O. G.0565.07, G.0686.09, G.A022.11N and G.0702.12), and the Research Council of the KU Leuven (GOA 2009/07, EF/95/010, PFV/10/006, OT/12/091 and GOA 14011).

Immune abnormalities have been found in many patients receiving anti-epileptic drugs. However, the effects of carbamazepine are still conflicting. We report the case of a 31-year-old woman who began carbamazepine treatment because of idiopathic epilepsy of adulthood. After three years of treatment she developed arthralgias and malaise. Complete immunologic evaluation showed a total absence of immunoglobulin M with decreased levels of immunoglobulin A, positive antinuclear antibodies and monoclonal paraproteinemia type IgG-kappa. The possibility of B cell lymphoma or myeloma was ruled out. Skin testing was negative. Bone marrow examination was normal. After carbamazepine discontinuation, levels of IgA and IgM increased until reaching normal values over 3 years. The monoclonal gammopathy of undetermined significance also disappeared over this period. During this period of immunodeficiency, the patient did not complain of any infectious complications.

Basal release of [3H]catecholamine ([3H]CA) from rabbit carotid bodies (CBs), previously incubated in the presence of [3H]tyrosine, was not significantly modified by prostaglandin E2 (PGE2). On the contrary, PGE2 (3-300 nM) produced a dose-dependent inhibition of the low PO2-evoked release of [3H]CA. The inhibition was greatest (55%) at a low intensity of hypoxic stimulation (incubating solution PO2 approximately 66 mmHg) and decreased with increasing intensities of hypoxia. Chronic denervation of the CB did not modify the response to PGE2. The release of [3H]CA induced by incubating the CBs in a hypercapnic-acidic solution (PCO2 approximately 132 mmHg; pH = 6.60) and by dinitrophenol (100 microM) was not significantly modified by 300 nM PGE2. PGE2 (300 nM) inhibited the release of [3H]CA elicited by incubating the CBs in a high K+ (35 mM)-containing solution. The release response elicited by high K+ (25 mM) was strongly augmented by a dihydropyridine agonist of Ca2+ channels, Bay K 8644, at a concentration of 1 microM. The Bay K 8644 effect was partly inhibited by PGE2 (300 nM). Using whole-cell recordings in freshly dispersed or short-term cultured chemoreceptor cells from adult rabbits it was found that Ca2+ currents (ICa) were reversibly inhibited by bath application of PGE2. A good parallelism exits between the dose-response curves for PGE2 inhibition of ICa in isolated chemoreceptor cells and high extracellular [K+]- or hypoxia-evoked release of [3H]CA from the whole CB.(ABSTRACT TRUNCATED AT 250 WORDS)

1. Adult rabbit carotid body chemoreceptor cells, enzymatically dispersed and short-term cultured, exhibit an inactivating outward K+ current that is reversibly inhibited by low PO2. In the present work we have characterized the biophysical and pharmacological properties of this current using the whole-cell voltage clamp recording technique. 2. Inactivating current was recorded after blockage of Ca2+ currents with extracellular Co2+, Cd2+, or after complete washing out of Ca2+ channels. 3. The threshold of activation of this inactivating current was about -40 mV. Current activated very quickly (mean rise time 4.8 +/- 0.42 ms at +60 mV) but inactivated more slowly. Inactivation was well fitted by two exponentials with time constants of 79.7 +/- 6.6 and 824 +/- 42.8 ms (at +40 mV). The inactivation process showed a little voltage dependence. 4. The steady-state inactivation was well fitted by a Boltzman function. Inactivation was fully removed at potentials negative to -80 mV and was complete at voltages near -10 mV; 50% inactivation occurred at -41 mV. 5. Recovery from inactivation had several components and was voltage dependent. Initial recovery was fast, but full recovery, even at -100 mV, required more than 30 s. 6. Inactivating current was selectively blocked by 4-aminopyridine (4-AP), in a dose-dependent manner (IC50, 0.2 mM). The duration of chemoreceptor cells action potentials was augmented by 1 mM 4-AP from 2.3 +/- 0.36 to 7.0 +/- 0.25 ms at 0 mV. Tetraethylamonium (TEA), at concentrations above 5 mM, blocked inactivating and non-inactivating components of the whole K+ current. 7. Inactivating current was modulated by cyclic AMP (cAMP). Bath application of 2 mM dibutyryl cAMP reduced peak amplitude by 18.7 +/- 2.9% (at +30 mV) and slowed down the rise time of the current. The effect was not voltage dependent. Forskolin (10-20 microM) also affected inactivating current, by accelerating the inactivation process. In the same preparations neither dibutyryl cAMP nor forskolin affected Ca2+ currents. 8. It is concluded that modulation of K+ channels by cAMP might play a physiological role potentiating the low PO2 inhibition of K+ channels.

Producción Científica, Objective: Vascular smooth muscle cells (VSMCs) contribute significantly to occlusive vascular diseases by virtue of their ability to switch to a noncontractile, migratory, and proliferating phenotype. Although the participation of ion channels in this phenotypic modulation (PM) has been described previously, changes in their expression are poorly defined because of their large molecular diversity. We obtained a global portrait of ion channel expression in contractile versus proliferating mouse femoral artery VSMCs, and explored the functional contribution to the PM of the most relevant changes that we observed. Methods and Results: High-throughput real-time polymerase chain reaction of 87 ion channel genes was performed in 2 experimental paradigms: an in vivo model of endoluminal lesion and an in vitro model of cultured VSMCs obtained from explants. mRNA expression changes showed a good correlation between the 2 proliferative models, with only 2 genes, Kv1.3 and Kvβ2, increasing their expression on proliferation. The functional characterization demonstrates that Kv1.3 currents increased in proliferating VSMC and that their selective blockade inhibits migration and proliferation. Conclusion: These findings establish the involvement of Kv1.3 channels in the PM of VSMCs, providing a new therapeutical target for the treatment of intimal hyperplasia., Ministerio de Sanidad, Consumo y Bienestar Social - Instituto de Salud Carlos III (grants R006/009, FS041139-0 and PI041044), Ministerio de Ciencia, Innovación y Universidades (grants BFU2004-05551 and BFU2007-61524), Junta de Castilla y León (grant GR242)

Producción Científica, Aims: Vascular smooth muscle cell (VSMC) proliferation is involved in cardiovascular pathologies associated with unwanted arterial wall remodelling. Coordinated changes in the expression of several K+ channels have been found to be important elements in the phenotypic switch of VSMCs towards proliferation. We have previously demonstrated the association of functional expression of Kv3.4 channels with proliferation of human uterine VSMCs. Here, we sought to gain deeper insight on the relationship between Kv3.4 channels and cell cycle progression in this preparation. Methods and results: Expression and function of Kv3.4 channels along the cell cycle was explored in uterine VSMCs synchronized at different checkpoints, combining real-time PCR, western blotting, and electrophysiological techniques. Flow cytometry, Ki67 expression and BrdU incorporation techniques allowed us to explore the effects of Kv3.4 channels blockade on cell cycle distribution. We found cyclic changes in Kv3.4 and MiRP2 mRNA and protein expression along the cell cycle. Functional studies showed that Kv3.4 current amplitude and Kv3.4 channels contribution to cell excitability increased in proliferating cells. Finally, both Kv3.4 blockers and Kv3.4 knockdown with siRNA reduced the proportion of proliferating VSMCs. Conclusion: Our data indicate that Kv3.4 channels exert a permissive role in the cell cycle progression of proliferating uterine VSMCs, as their blockade induces cell cycle arrest after G2/M phase completion. The modulation of resting membrane potential (VM) by Kv3.4 channels in proliferating VSMCs suggests that their role in cell cycle progression could be at least in part mediated by their contribution to the hyperpolarizing signal needed to progress through the G1 phase., Ministerio de Sanidad, Consumo y Bienestar Social - Instituto de Salud Carlos III (grants R006/009 and PI041044), Ministerio de Ciencia, Innovación y Universidades (grants BFU2004-05551 and BFU2007-61524), Junta de Castilla y León (grant GR242)

The characterization of the molecular mechanisms involved in low-oxygen chemot ansduction has been an active field of research since the first description of an oxygen-sensitive K + channel in rabbit carotid body (CB) chemoreceptor cells. As a result, a large number of components of the transduction cascade, from O 2 sensors to 0 2 -sensitive ion channels, have been found. Although the endpoints of the process are analogous, the heterogeneity of the elements involved in the different chemoreceptor tissues precludes a unifying theory of hypoxic signaling, and it has been a source of controversy. However, when these molecular constituents of the hypoxic cascade are brought back to their physiological context, it becomes clear that the diversity of mechanisms is necessary to build up an integrated cellular response that demands the concerted action of several O 2 sensors and several effectors.