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Search Results: 1 - 10 of 31188 matches for " Ibrahim González-Marrero "
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High Blood Pressure Effects on the Brain Barriers and Choroid Plexus Secretion  [PDF]
Ibrahim González-Marrero, Leandro Casta?eyra-Ruiz, Juan M. González-Toledo, Agustín Casta?eyra-Ruiz, Héctor de Paz-Carmona, Lidia Ruiz-Mayor, Agustín Casta?eyra-Perdomo, Emilia M. Carmona-Calero
Neuroscience & Medicine (NM) , 2012, DOI: 10.4236/nm.2012.31009
Abstract: High blood pressure produces ventricular dilation, variations in circumventricular organs and changes in the cerebrospinal fluid compositions. On the other hand, chronic hypertension in spontaneously hypertensive rats can cause changes in the integrity of the brain barriers: blood-cerebrospinal fluid barrier and blood brain barrier. The permeability of the brain barriers can be studied by using transthyretin and S-100β. In the present work we study the integrity of the brain barrier and the choroid plexus function variations in arterial hypertension. Control rats and spontaneously hypertensive rats were used and the choroid plexus were processed by immunohistochemistry with anti-transthyretin and anti-vasopressin. Western blot was also performed in cerebrospinal fluid, serum and choroid plexus using anti-S-100β, anti-transthyretin. The accumulation of transthyretin immunoreactive was bigger in spontaneously hypertensive rats with respect to the control. Vasopressin was also higher in spontaneously hypertensive rats with respect to the control. Western blot showed that transthyretin tetramer was higher in the spontaneously hypertensive rats than in the control rats. The expression of transthyretin monomer was lower in hypertensive rats than the control in the cerebrospinal fluid, the transthyretin monomer reaction in the blood was stronger in hypertensive than in control rats. Western blot for the S-100 β showed an increase in blood and cerebrospinal fluid of hypertensive rats. The high blood pressure produces a disruption of the blood brain barrier and blood to cerebrospinal fluid barrier that allows extravasations from the cerebrospinal fluid to the blood and from the blood to the cerebrospinal fluid.
Hypertension effects on p73 expression in the rat circumventricular organs and cerebrospinal fluid  [PDF]
Emilia M. Carmona-Calero, Ibrahim González-Marrero, Manuela Casta?eyra-Martin, Juan M. González-Toledo, Leandro Casta?eyra-Ruiz, Héctor de Paz-Carmona, Agustín Casta?eyra-Ruiz, Lidia Ruiz-Mayor, Agustín Casta?eyra-Perdomo
World Journal of Neuroscience (WJNS) , 2012, DOI: 10.4236/wjns.2012.22010
Abstract: It has been reported that spontaneously hypertensive rats (SHR) show ventricular dilation, changes in CSF proteins and variations in the circumventricular organs (CVO) such as: the subcommissural organ (SCO), the subfornical organ (SFO) and the area postrema (AP) which are located in the walls of the third and fourth ventricles. On the other hand, p73 proteins are present in cells of the central nervous system (CNS) such as circumventricular structures and the neuroepithelium which are altered in ventricular dilation. The purpose of the present work is to study the TAp73 isoform expression in the circumventricular organs (CVO) and their variations in ventricular dilatation and arterial hypertension. Brains and cerebrospinal fluid (CSF) from control Wistar-Kyoto rats (WKY) and SHR were used. The paraffin sections containing the CVO were immunohistochemically proc-essed with anti-TAp73 and by western blot, p73 bands in the CSF and circumventricular organ extract were also identified. The western blot study showed bands marked with p73 in the CSF and CVO, the p73 band expression was bigger in the SHR than in the WKY rats. We also found stronger markings in the SFO, SCO and AP of the hypertensive rats than in the WKY rats. It could be concluded that hypertension in the SHR produces altera-tions in the relationship between the p73 protein, circumventricular structures and CSF.
High Blood Pressure Effects on the Blood to Cerebrospinal Fluid Barrier and Cerebrospinal Fluid Protein Composition: A Two-Dimensional Electrophoresis Study in Spontaneously Hypertensive Rats
Ibrahim González-Marrero,Leandro Castañeyra-Ruiz,Juan M. González-Toledo,Agustín Castañeyra-Ruiz
International Journal of Hypertension , 2013, DOI: 10.1155/2013/164653
Abstract:
High Blood Pressure Effects on the Blood to Cerebrospinal Fluid Barrier and Cerebrospinal Fluid Protein Composition: A Two-Dimensional Electrophoresis Study in Spontaneously Hypertensive Rats
Ibrahim González-Marrero,Leandro Casta?eyra-Ruiz,Juan M. González-Toledo,Agustín Casta?eyra-Ruiz,Hector de Paz-Carmona,Rafael Castro,Juan R. Hernandez-Fernaud,Agustín Casta?eyra-Perdomo,Emilia M. Carmona-Calero
International Journal of Hypertension , 2013, DOI: 10.1155/2013/164653
Abstract: The aim of the present work is to analyze the cerebrospinal fluid proteomic profile, trying to find possible biomarkers of the effects of hypertension of the blood to CSF barrier disruption in the brain and their participation in the cholesterol and β-amyloid metabolism and inflammatory processes. Cerebrospinal fluid (CSF) is a system linked to the brain and its composition can be altered not only by encephalic disorder, but also by systemic diseases such as arterial hypertension, which produces alterations in the choroid plexus and cerebrospinal fluid protein composition. 2D gel electrophoresis in cerebrospinal fluid extracted from the cistern magna before sacrifice of hypertensive and control rats was performed. The results showed different proteomic profiles between SHR and WKY, that α-1-antitrypsin, apolipoprotein A1, albumin, immunoglobulin G, vitamin D binding protein, haptoglobin and α-1-macroglobulin were found to be up-regulated in SHR, and apolipoprotein E, transthyretin, α-2-HS-glycoprotein, transferrin, α-1β-glycoprotein, kininogen and carbonic anhidrase II were down-regulated in SHR. The conclusion made here is that hypertension in SHR produces important variations in cerebrospinal fluid proteins that could be due to a choroid plexus dysfunction and this fact supports the close connection between hypertension and blood to cerebrospinal fluid barrier disruption. 1. Introduction Cerebrospinal fluid is a functional system closely connected to the brain, and changes or variations in the CSF may mean an alteration in the brain expressed by encephalic disorders. However, the composition of CSF may also be altered by systemic diseases, such as arterial hypertension, and cerebral ventricular dilatation, changes in CSF protein, and variations of the choroid plexus and other circumventricular organs (CVO) have been described in spontaneously hypertensive rats (SHR) [1–5]. Therefore, SHR develop hydrocephalus and experimental studies explain that hydrocephalus induces alterations in CSF since there are disturbances, in the hydrocephalic brain, of oxidative metabolism and neurotransmission and perhaps damage to periventricular cells, particularly when intracranial pressure is elevated [6]. The sharp increase in systemic blood pressure only causes an acute increase in CSF pressure in normotensive animals and not in hypertensive patients [6]. The CSF pressure of SHR showed greater protection to the acute effects of phenylephrine than in control Wistar-Kyoto (WKY) rats, but a permeability increase of the blood to cerebrospinal fluid barrier to sucrose in
Luteinizing Hormone-Releasing Hormone Distribution in the Anterior Hypothalamus of the Female Rats
Leandro Casta?eyra-Ruiz,Ibrahim González-Marrero,Agustín Casta?eyra-Ruiz,Juan M. González-Toledo,María Casta?eyra-Ruiz,Héctor de Paz-Carmona,Agustín Casta?eyra-Perdomo,Emilia M. Carmona-Calero
ISRN Anatomy , 2013, DOI: 10.5402/2013/870721
Abstract: Luteinizing hormone-releasing hormone (LHRH) neurons and fibers are located in the anteroventral hypothalamus, specifically in the preoptic medial area and the organum vasculosum of the lamina terminalis. Most luteinizing hormone-releasing hormone neurons project to the median eminence where they are secreted in the pituitary portal system in order to control the release of gonadotropin. The aim of this study is to provide, using immunohistochemistry and female brain rats, a new description of the luteinizing hormone-releasing hormone fibers and neuron localization in the anterior hypothalamus. The greatest amount of the LHRH immunoreactive material was found in the organum vasculosum of the lamina terminalis that is located around the anterior region of the third ventricle. The intensity of the reaction of LHRH immunoreactive material decreases from cephalic to caudal localization; therefore, the greatest immunoreaction is in the organum vasculosum of the lamina terminalis, followed by the dorsomedial preoptic area, the ventromedial preoptic area, and finally the ventrolateral medial preoptic area, and in fibers surrounding the suprachiasmatic nucleus and subependymal layer on the floor of the third ventricle where the least amount immunoreactive material is found. 1. Introduction The luteinizing hormone-releasing hormone (LHRH) is a gonadotropin releasing hormone (GnRH), which acts on the pituitary hormones as a follicle stimulating hormone (FSH) and luteinizing hormone (LH), which act on the gonads, [1]. The GnRH neurons are originated in the nasal epithelium and migrate accompanying the fibers of the vomeronasal and terminal nerves [2, 3] up to the anterobasal part of the brain, where they enter the brain together with nerve terminals and then move caudally to the preoptic hypothalamus, where GnRH neurons are definitively located [2, 4]. These GnRH neurons and fibers are mainly located in the anteroventral third ventricle region, specifically in the preoptic area (PA) and the organum vasculosum of the lamina terminalis (OVLT) [5]. The anterior hypothalamus is the major region of the diencephalon implicated in the development of the olfactory system and the sexual differentiation of the brain. Most of the GnRH neurons axons project to the external zone of the median eminence where is GnRH secreted into the pituitary portal vasculature to control the release of gonadotropin [6–8]. The preoptic area (PA) is part of the anterior hypothalamus and is confined to the anteroventral region of the third ventricle (AV3V); the PA is divided into, the medial
Angiotensin II, Vasopressin, and Collagen-IV Expression in the Subfornical Organ in a Case of Syndrome of Inappropriate ADH
Emilia M. Carmona-Calero,Juan M. González-Toledo,Leandro Casta?eyra-Ruiz,Ibrahim González-Marrero,María Casta?eyra-Ruiz,Héctor de Paz-Carmona,Agustín Casta?eyra-Ruiz,Nélida Rancel-Torres,Agustín Casta?eyra-Perdomo
Advances in Endocrinology , 2014, DOI: 10.1155/2014/179795
Abstract: The syndrome of inappropriate antidiuretic hormone (SIADH) is a disease characterized by hyponatremia and hyperosmolarity of urine where vasopressin and angiotensin II are implicated in the alteration of salt water balance and cardiovascular and blood pressure regulation. The aim of this study is to analyse the expression of substances related with cardiovascular and salt water regulation in the subfornical organ in a case of SIADH. Two brains, one taken from a 66-year-old man with SIADH and the other from a 63-year-old man without SIADH, were used. Immunohistochemical study was performed using anti-angiotensin II, anti-vasopressin, and anti-collagen-VI as primary antibodies. Angiotensin and vasopressin immunoreaction were found in neurons, in perivascular spaces, and in the ependymal layer in the subfornical organ in both cases. However, in the SIADH case, the angiotensin II and collagen-IV expression in the SFO were different suggesting this organ’s possible participation in the physiopathology of SIADH. 1. Introduction Diabetes insipidus (DI), syndrome of inappropriate antidiuretic hormone (SIADH), and syndrome cerebral salt-wasting (CSW) are three pathologies with hyponatremia and hyperosmolarity and differentiation between them is important to prescribe the most appropriate treatments [1, 2]. SIADH is a disease which is characterized by the hyponatremia and hyperosmolarity of urine [3–5]. There are well known causes for this syndrome, such as neoplasmatic processes, disorders of the central nervous system, lung diseases, and the side effects of drugs. A study [6] of a large group of patients has revealed that SIADH occurs in 3% of patients with head and neck cancer, in 0.7% of patients with non-small-cell lung cancer, and in 15% of cases of small-cell lung cancer [6]. The standard therapy for SIADH is to treat the underlying malignant disease. If this is not possible or if the disease has become refractory, other treatment methods are available such as water restriction, demeclocycline therapy, or, in severe cases, infusion of hypertonic saline together with furosemide during treatment [6]. Total body water and tonicity are strictly regulated by the renal action of the antidiuretic hormone (ADH), renin-angiotensin-aldosterone system, and norepinephrine and by the thirst mechanism. Abnormalities in water balance are manifested in SIADH as sodium disturbances-hyponatremia and hypernatremia [6]. On the other hand, the presence of VAS, AGII, and TH and their implication in cardiovascular, salt water balance and blood pressure regulation have long been
Guerrero 2011: mitos, continuidades y rupturas
Secundino González Marrero
El Cotidiano , 2011,
Abstract: Las elecciones celebradas en Guerrero en enero de 2011 han servido, a nuestro juicio, para poner en cuestión varios de los mitos recurrentes sobre los procesos electorales en la entidad. Se insertan asimismo en una práctica extendida de presentación, por parte de un partido o coalición, de un candidato que hasta poco antes pertenecía a otro y que acaba ganando la elección. Ello confirmaría, de igual manera, el alto grado de "personalización" de la política mexicana, donde ni la identidad partidista ni la escala izquierda - derecha parecen servir de mucho como instrumentos de prospectiva electoral.
Evolución del tratamiento quirúrgico del desprendimiento de la retina en los últimos cincuenta a?os (septiembre 1954-agosto 2004)
González Urbaneja,Ibrahim;
Gaceta Médica de Caracas , 2005,
Abstract: in the following study, several dates are mentioned related to major historical events; some even considered as determinant moments in the evolution of retinal detachment surgery. under a comprehensive perspective, one could forward some inferences, as for example: 1. prior to 1920 there was no scientific treatment whatsoever for retinal detachment patients. 2. between 1949 and 1957 there were significant contributions to the clinical study of the detached retina and to its surgical practice, which account as the "birth of the modern era" of retinal surgery. 3. this inference draws the conclusion that even when the modern phase starts with some delay, the decade of the 80s starts at a vertiginous pace showing remarkable progress with the appearance of laser, vitreotome, surgical microscope, the optical coherent tomography and other technologies that make possible the close endo-ocular microsurgery. the author presents a casuistic universe of 4 319 patients treated, using 5 085 different procedures of surgical methods, which account for his accomplishment of 50 years of medical practice. another relevant data here showed by the author, is a total high patients? recovery rate of 91.3 %, and a 96 % percent recovery rate obtained within the period 1989-2004. such results are similar to the ones recorded in the best specialty institutions around the world.
Evolución del tratamiento quirúrgico del desprendimiento de la retina en los últimos cincuenta a os (septiembre 1954-agosto 2004)
Ibrahim González Urbaneja
Gaceta Médica de Caracas , 2005,
Abstract: En el curso del presente trabajo se van enumerando fechas relacionadas con eventos históricos importantes y, muchas veces determinantes en la evolución de la cirugía del desprendimiento de la retina. Interrelacionando estos momentos históricos se pueden deducir algunas inferencias, a saber: 1. Antes de 1920 no existía tratamiento científico alguno, para pacientes con desprendimiento de la retina. 2. Que entre 1949 y 1957 se suscitan u ocurren aportes trascendentes para el estudio clínico de la retina desprendida y la práctica de la cirugía de esta afección, razón por la cual se la considera como el comienzo de la "era moderna" de la cirugía de la retina. 3. Esta inferencia permite concluir que si bien la etapa moderna comienza con cierto retraso, el progreso es vertiginoso a partir de los a os ochenta, con aportes como el láser, el renovado microscopio quirúrgico, la tomografía óptica coherente, vitriotomos, y otros factores que conducen a la culminación de la microcirugía endoocular cerrada. El autor presenta su casuística de 4 319 pacientes tratados, utilizando 5 085 procedimientos de diferentes métodos quirúrgicos, que resumen su labor realizada durante cincuenta a os. Obtiene un alto porcentaje de curación de esta afección, del 91,3 % del total de los pacientes y, del 96 % en el período comprendido entre 1989 y 2004. Resultados similares a los obtenidos en los mejores centros especializados, de otras latitudes. In the following study, several dates are mentioned related to major historical events; some even considered as determinant moments in the evolution of retinal detachment surgery. Under a comprehensive perspective, one could forward some inferences, as for example: 1. Prior to 1920 there was no scientific treatment whatsoever for retinal detachment patients. 2. Between 1949 and 1957 there were significant contributions to the clinical study of the detached retina and to its surgical practice, which account as the "birth of the modern era" of retinal surgery. 3. This inference draws the conclusion that even when the modern phase starts with some delay, the decade of the 80s starts at a vertiginous pace showing remarkable progress with the appearance of laser, vitreotome, surgical microscope, the optical coherent tomography and other technologies that make possible the close endo-ocular microsurgery. The author presents a casuistic universe of 4 319 patients treated, using 5 085 different procedures of surgical methods, which account for his accomplishment of 50 years of medical practice. Another relevant data here showed by the author, is a to
Radicales libres: Algunas consideraciones clínicas
González-Urbaneja,Ibrahim;
Gaceta Médica de Caracas , 2006,
Abstract: in most known chemical substances, electrons couple and travel with their negative charge describing a constant orbit around the atomic nucleus. during the second half of the xxth century it became possible to determine chemical species that contained one or more electrons who perform their orbital track joint on an odd number basis or unevenly, provoking a considerable unstability in the molecular equilibrium which can only be re-established when they capture or adhere from the environment, the extra electron they require to configure the essential electronic parity. these chemical substances that contain an odd-number structure are called free radicals, and have special characteristics that result in serious tissue damage. defaults (or deficiencies) in the mitocondrial process of aerobic breath, constantly provoke oxygenated free radicals or oxi-radicals, whose pernicious effects are countered with so called antioxidant agents. basic biological functions as well as countless corporal pathologies, are tightly linked to the behaviour of free radicals. in fact, it is believed that decease, as a universal phenomenon observed in all living creatures in our planet, is affected by the process of these microbiological delinquents. we make some considerations about: atherogenesis, swellings, tobacco smoke, aging and cancer.
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