289 research outputs found

    Role of voltage-gated proton channel (Hv1) in cancer biology

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    The acid-base characteristics of tumor cells and the other elements that compose the tumor microenvironment have been topics of scientific interest in oncological research. There is much evidence confirming that pH conditions are maintained by changes in the patterns of expression of certain proton transporters. In the past decade, the voltage-gated proton channel (Hv1) has been added to this list and is increasingly being recognized as a target with onco-therapeutic potential. The Hv1 channel is key to proton extrusion for maintaining a balanced cytosolic pH. This protein-channel is expressed in a myriad of tissues and cell lineages whose functions vary from producing bioluminescence in dinoflagellates to alkalizing spermatozoa cytoplasm for reproduction, and regulating the respiratory burst for immune system response. It is no wonder that in acidic environments such as the tumor microenvironment, an exacerbated expression and function of this channel has been reported. Indeed, multiple studies have revealed a strong relationship between pH balance, cancer development, and the overexpression of the Hv1 channel, being proposed as a marker for malignancy in cancer. In this review, we present data that supports the idea that the Hv1 channel plays a significant role in cancer by maintaining pH conditions that favor the development of malignancy features in solid tumor models. With the antecedents presented in this bibliographic report, we want to strengthen the idea that the Hv1 proton channel is an excellent therapeutic strategy to counter the development of solid tumors

    Radiation-sparing managements for cervical cancer: a developing countries perspective

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    Cervical cancer is the seventh most frequent cancer worldwide but more than 80% of cases occur in developing countries. Till date, radiation therapy with external beam and brachytherapy remains as the core treatment for most stages of cervical cancer. However, radiation treatment protocols and equipment modelled on the best developed countries can be seldom applied directly to developing countries owing to financial constraints and lack of qualified personnel, thus, a substantial proportion of patients do not have access to even palliative radiation therapy. Treatment options when the standard therapy is either not available or difficult to reproduce in particular settings is highly desirable with the potential to save lives that otherwise could be lost by the lack of adequate treatment. These options of treatment ideally had to have show, 1) that these are not inferior to the "standard" in terms of either survival or quality of life; 2) that these can be delivered in settings were the "standard" is not available or if available its quality is poor; and 3) that the treatment option be accepted by the population to be treated. Based on these considerations, it is obvious that cervical cancer patients, particularly those who live in countries with limited resources and therefore may not have sufficient radiation therapy resources are in need of newer therapeutical options. There is now a considerable amount of information emanating from clinical studies where surgery has a major role in treating this disease. These forms of "radiation-sparing" treatments include total mesometrial resection that could make unnecessary the use of adjuvant radiation; neoadjuvant chemotherapy that could avoid the use of adjuvant radiation in around 85% of patients and preoperative chemoradiation that could make brachytherapy dispensable. The feasibility and therapeutical value of these potential forms of management need to be prospectively evaluated

    Aquaporin Gating: A New Twist to Unravel Permeation through Water Channels

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    Aquaporins (AQPs) are small transmembrane tetrameric proteins that facilitate water, solute and gas exchange. Their presence has been extensively reported in the biological membranes of almost all living organisms. Although their discovery is much more recent than ion transport systems, different biophysical approaches have contributed to confirm that permeation through each monomer is consistent with closed and open states, introducing the term gating mechanism into the field. The study of AQPs in their native membrane or overexpressed in heterologous systems have experimentally demonstrated that water membrane permeability can be reversibly modified in response to specific modulators. For some regulation mechanisms, such as pH changes, evidence for gating is also supported by high-resolution structures of the water channel in different configurations as well as molecular dynamics simulation. Both experimental and simulation approaches sustain that the rearrangement of conserved residues contributes to occlude the cavity of the channel restricting water permeation. Interestingly, specific charged and conserved residues are present in the environment of the pore and, thus, the tetrameric structure can be subjected to alter the positions of these charges to sustain gating. Thus, is it possible to explore whether the displacement of these charges (gating current) leads to conformational changes? To our knowledge, this question has not yet been addressed at all. In this review, we intend to analyze the suitability of this proposal for the first time.Fil: Ozu, Marcelo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Biodiversidad y Biología Experimental y Aplicada. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Biodiversidad y Biología Experimental y Aplicada; ArgentinaFil: Alvear Arias, Juan José. Universidad de Valparaíso; ChileFil: Fernandez, Miguel. Universidad de Valparaíso; ChileFil: Caviglia, Agustín. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Biodiversidad y Biología Experimental y Aplicada. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Biodiversidad y Biología Experimental y Aplicada; ArgentinaFil: Peña Pichicoi, Antonio. Universidad de Valparaíso; ChileFil: Carrillo, Christian. Universidad de Valparaíso; ChileFil: Carmona, Emerson. No especifíca;Fil: Otero Gonzalez, Anselmo. Universidad de La Habana; CubaFil: Garate, José Antonio. Universidad de Valparaíso; ChileFil: Amodeo, Gabriela. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Biodiversidad y Biología Experimental y Aplicada. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Biodiversidad y Biología Experimental y Aplicada; ArgentinaFil: Gonzalez, Carlos. Universidad de Valparaíso; Chil

    Urinary Kininogen-1 and Retinol binding protein-4 respond to Acute Kidney Injury: Predictors of patient prognosis?

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    Implementation of therapy for acute kidney injury (AKI) depends on successful prediction of individual patient prognosis. Clinical markers as serum creatinine (sCr) have limitations in sensitivity and early response. The aim of the study was to identify novel molecules in urine which show altered levels in response to AKI and investigate their value as predictors of recovery. Changes in the urinary proteome were here investigated in a cohort of 88 subjects (55 AKI patients and 33 healthy donors) grouped in discovery and validation independent cohorts. Patients'urine was collected at three time points: within the first 48 h after diagnosis(T1), at 7 days of follow-up(T2) and at discharge of Nephrology(T3). Differential gel electrophoresis was performed and data were confirmed by Western blot (WB), liquid chromatography/mass spectrometry (LC-MS/MS) and enzyme-linked immunosorbent assay (ELISA). Retinol binding protein 4 (RBP4) and kininogen-1 (KNG1) were found significantly altered following AKI. RBP4 increased at T1, and progressively decreased towards normalization. Maintained decrease was observed for KNG1 from T1. Individual patient response along time revealed RBP4 responds to recovery earlier than sCr. In conclusion, KNG1 and RBP4 respond to AKI. By monitoring RBP4, patient's recovery can be anticipated pointing to a role of RBP4 in prognosis evaluation.Funding: from Instituto de Salud Carlos III: FIS PI11/01401, PI13/01873, FIS IF08/3667-1, CP09/00229, PI13/00047, PI10/00624, ISCIII-RETIC REDinREN RD012/0021. FEDER funds, Comunidad de Madrid/CIFRA S2010/BMD-2378, Programa Intensificación Actividad Investigadora (ISCIII/Agencia Laín-Entralgo/CM) to AO, IDCSalud (3371/002) and Fundación Conchita Rábago de Jiménez Díaz, Proteomic Facility from Universidad Complutense de Madrid-Fundación Parque Científico de Madrid (UCM-FPCM), Spain, a member of ProteoRed-ISCIII Network member of ProteoRed- ISCIII Networ

    Looking for the traces of the last hunter-gatherers : Geophysical survey in the Mesolithic shell middens of the Sado valley (southern Portugal)

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    This paper presents the results of an application of geophysical surveying methods to Mesolithic sites in Portugal. Magnetic gradiometry maps have been produced at the sites of Vale de Romeiras and Poças de São Bento. At the latter, three excavation seasons have provided information to test the results of the survey. It is concluded that these techniques can be considered efficient tools for the delimitation of the sites and for the identification of Mesolithic and Neolithic structures. Looking for the traces of the last hunter–gatherers: Geophysical survey in the Mesolithic shell middens of the Sado valley (southern Portugal).info:eu-repo/semantics/publishedVersio

    Comparación de mediciones de diámetro de fibra entre Minifiberec, Laserscan y OFDA2000 en muestras de tops de lana

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    El diámetro medio de fibras es la característica más importante para describir la calidad de las fibras animales.Por lo tanto su medición objetiva de manera precisa y exacta tiene un interés particular para propósitos de selección animal, uso industrial potencial y fijación de precios (Walkerycol.,2018). Si bien existen diferentes equipos tradicionalmente utilizados para la medición del diámetro como el OFDA2000 (IWTO47) o el Laserscan (IWTO12), los resultados obtenidos con nuevos desarrollos tecnológicos como el MINIFIBEREC se presentan como alternativas con un buen nivel de precisión desde lo metrológico y competitivo desde lo comercial.Estación Experimental Agropecuaria BarilocheFil: Arias Huamani, Katherine Daniela. Universidad Nacional Micaela Bastidas de Apurímac; PerúFil: Quispe Peña, Edgar Carlos. Universidad Nacional Autonoma de Chota, PerúFil: Quispe Bonilla, Max David. Maxcorp Technologies S.A.C., PerúFIl: Sacchero, Diego. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Bariloche. Área Producción Animal. Laboratorio de lanas; Argentin

    Ecosistema de datos para clima y agricultura en Honduras y Guatemala

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    Centroamérica es una de las regiones más vulnerables a los efectos de la variabilidad climática, eventos extremos, y el cambio climático. Uno de los objetivos de la Iniciativa AgriLAC Resiliente es consolidar un ecosistema digital alrededor de la gestión del riesgo y la intensificación sustentable en los sistemas agroalimentarios en Guatemala y Honduras, estableciendo servicios digitales y sistemas de apoyo a la toma de decisiones. Un paso crucial en la consolidación del ecosistema digital es entender y transformar el (sub)ecosistema de datos en clima y agricultura, de manera tal que dicho (sub)ecosistema pueda soportar funciones como la generación de contenidos y la diseminación de recomendaciones a productores y otros actores de los sistemas agroalimentarios. La falta de estandarización en los procesos de recolección, limpieza y almacenamiento conlleva un gran reto a la hora de integrar la información de diferentes fuentes e instituciones. En este documento se resumen las características más importantes del ecosistema actual de datos en Guatemala y Honduras, y se proponen procesos y herramientas a través de las cuales se espera gestionar una transformación de dicho ecosistem

    Blood stasis imaging predicts cerebral microembolism during acute myocardial infarction

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    Background: Cardioembolic stroke is a major source of mortality and disability worldwide. The authors hypothesized that quantitative characterization of intracardiac blood stasis may be useful to determine cardioembolic risk in order to personalize anticoagulation therapy. The aim of this study was to assess the relationship between image-based metrics of blood stasis in the left ventricle and brain microembolism, a surrogate marker of cardiac embolism, in a controlled animal experimental model of acute myocardial infarction (AMI). -- Methods: Intraventricular blood stasis maps were derived from conventional color Doppler echocardiography in 10 pigs during anterior AMI induced by sequential ligation of the mid and proximal left anterior descending coronary artery (AMI-1 and AMI-2 phases). From these maps, indices of global and local blood stasis were calculated, such as the average residence time and the size and ratio of contact with the endocardium of blood regions with long residence times. The incidence of brain microemboli (high-intensity transient signals [HITS]) was monitored using carotid Doppler ultrasound. -- Results: HITS were detected in 0%, 50%, and 90% of the animals at baseline and during AMI-1 and AMI-2 phases, respectively. The average residence time of blood in the left ventricle increased in parallel. The residence time performed well to predict microemboli (C-index = 0.89, 95% CI, 0.75–1.00) and closely correlated with the number of HITS (R = 0.87, P < .001). Multivariate and mediation analyses demonstrated that the number of HITS during AMI phases was best explained by stasis. Among conventional echocardiographic variables, only apical wall motion score weakly correlated with the number of HITS (R = 0.3, P = .04). Mural thrombosis in the left ventricle was ruled out in all animals. -- Conclusions: The degree of stasis of blood in the left ventricle caused by AMI is closely related to the incidence of brain microembolism. Therefore, stasis imaging is a promising tool for a patient-specific assessment of cardioembolic risk.This study was supported by grant PI15/02211, Rio Hortega (CM17/00144), and Juan Rodés fellowships (JR15/00039) from Instituto de Salud Carlos III; grant DPI2016-75706-P and a Juan de la Cierva fellowship (IJCI-2014-19507) from Ministerio de Economía y Competitividad; synergy grant Y2018/BIO-4858-PREFI-CM from Comunidad Autónoma de Madrid; the European Union - European Regional Development Fund; by the Spanish Society of Cardiology (ISBI-DCM); by the University of California,San Diego, CTRI Galvanizing Engineering and Medicine Program; American Heart Association grant 16GRNT27250262; and National Institutes of Health UC CAI grant CII4560. P.M.-L. was also funded by CIBERCV. P.M.-L., L.R., J.C.A., and J.B. are inventors of a method for quantifying intracardiac stasis from imaging data under a Patent Cooperation Treaty patent application (WO2017091746A1)
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