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3.
Prog Biophys Mol Biol ; 136: 3-23, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29544820

RESUMEN

We review the salient evidence consistent with or predicted by the Hoyle-Wickramasinghe (H-W) thesis of Cometary (Cosmic) Biology. Much of this physical and biological evidence is multifactorial. One particular focus are the recent studies which date the emergence of the complex retroviruses of vertebrate lines at or just before the Cambrian Explosion of ∼500 Ma. Such viruses are known to be plausibly associated with major evolutionary genomic processes. We believe this coincidence is not fortuitous but is consistent with a key prediction of H-W theory whereby major extinction-diversification evolutionary boundaries coincide with virus-bearing cometary-bolide bombardment events. A second focus is the remarkable evolution of intelligent complexity (Cephalopods) culminating in the emergence of the Octopus. A third focus concerns the micro-organism fossil evidence contained within meteorites as well as the detection in the upper atmosphere of apparent incoming life-bearing particles from space. In our view the totality of the multifactorial data and critical analyses assembled by Fred Hoyle, Chandra Wickramasinghe and their many colleagues since the 1960s leads to a very plausible conclusion - life may have been seeded here on Earth by life-bearing comets as soon as conditions on Earth allowed it to flourish (about or just before 4.1 Billion years ago); and living organisms such as space-resistant and space-hardy bacteria, viruses, more complex eukaryotic cells, fertilised ova and seeds have been continuously delivered ever since to Earth so being one important driver of further terrestrial evolution which has resulted in considerable genetic diversity and which has led to the emergence of mankind.


Asunto(s)
Fenómenos Astronómicos , Origen de la Vida , Animales , Evolución Biológica , Retroviridae/fisiología
4.
Educ. med. super ; 28(1)ene.-mar. 2014.
Artículo en Español | CUMED | ID: cum-57792

RESUMEN

Se realizó una investigación descriptiva, en el campo de la educación de posgrado, con el objetivo de identificar las necesidades de aprendizaje sobre atención básica de las urgencias y emergencias médicas, de los médicos de la Atenció n Primaria de Salud en el Policlínico Universitario Mario Gutiérrez Ardaya de junio a diciembre de 2011. El sistema de métodos integró métodos empíricos, teóricos y de procesamiento estadísticos. Se empleó una guía de observación donde se evaluaron las habilidades específicas de los médicos, en la atención a las urgencias y emergencias. Se aplicó un cuestionario a 39 médicos, con el objetivo de conocer las temáticas con necesidades de capacitación en cuanto a la atención del paciente grave. Los temas sobre manejo de la vía aérea y ventilación, resucitación cardio-pulmonar-cerebral y el tratamiento del shock, fueron los de mayor relevancia. Se realizó una entrevista a 14 informantes clave y a 3 expertos, se definieron los temas de urgencias y emergencias que son de importancia para los médicos de la APS(AU)


A descriptive research study of the postgraduate education was conducted from June to December 2011. The objective was to identify the learning requirements in the field of basic care to medical urgencies and emergencies of the primary health care physicians who work in Mario Gutierrez Ardaya university polyclinic. The system comprised empirical, theoretical and statistical processing methods. An observational guide was used to evaluate the specific skills of physicians in the care of urgencies and emergencies. Thirty nine physicians answered a questionnaire to detect the topics in which they need training as to the care of the critical patient. The most relevant topics were found to be management of airways and ventilation, cardiopulmonary and cerebral resuscitation, and shock treatment. Fourteen key informants and 3 experts were interviewed, which resulted in the definition of the most important urgency and emergency topics for the primary health care physicians(AU)


Asunto(s)
Urgencias Médicas , Educación de Postgrado en Medicina , Aprendizaje Basado en Problemas , Aprendizaje
5.
CCH, Correo cient. Holguín ; 18(1): 154-158, ene.-mar. 2014. ilus
Artículo en Español | LILACS | ID: lil-706653

RESUMEN

El higroma quístico es el resultado de segmentos del saco linfático yugular que están fuera de sitio o de la falla de los espacios linfáticos para conectar con los principales canales linfáticos y constituye un tumor líquido claro, limpio y transparente; se diagnostica por ecografía en el primer trimestre del embarazo, porque se aprecia una masa que sobresale en la pared posterior o lateral del cuello, su aparición se asocia a cariotipos anormales, por lo cual es indispensable un estudio de cariotipo humano. El higroma quístico está asociado a trisomía 21, 18 y 13, entre otras. Se reportó el caso de una paciente con embarazo de 13,2 semanas, a la cual se le realizó marcador genético, detectándose un feto con una tumoración quística en la región cervical. Se decidió la interrupción de la gestación, mediante el uso de misoprostol, obteniéndose un higroma quístico como resultado anatomopatológico, que reafirmó el diagnóstico ultrasonográfico.


Cystic hygroma is a result of jugular lymph sac segments that are out of place or the failure of the lymphatic spaces to connect with the main lymphatic channels. It is a clear, clean and transparent liquid tumor, diagnosed by ultrasound in the first trimester of pregnancy, for a mass that protrudes in the back or side wall of the neck can be seen, its onset is associated with abnormal karyotypes, which is indispensable for a study of the human karyotype. Cystic hygroma is associated with trisomy 21, 18 and 13, among others. A case of a patient with pregnancy of 13.2 weeks, who underwent genetic marker, detecting a fetus with a cystic tumor in the cervical region was reported. Interruption of pregnancy was decided by using misoprostol, a cystic hygroma was revealed that confirmed the ultrasonographic diagnosis.

6.
Educ. med. super ; 28(1): 15-25, ene.-mar. 2014.
Artículo en Español | LILACS | ID: lil-711022

RESUMEN

Se realizó una investigación descriptiva, en el campo de la educación de posgrado, con el objetivo de identificar las necesidades de aprendizaje sobre atención básica de las urgencias y emergencias médicas, de los médicos de la Atenció n Primaria de Salud en el Policlínico Universitario Mario Gutiérrez Ardaya de junio a diciembre de 2011. El sistema de métodos integró métodos empíricos, teóricos y de procesamiento estadísticos. Se empleó una guía de observación donde se evaluaron las habilidades específicas de los médicos, en la atención a las urgencias y emergencias. Se aplicó un cuestionario a 39 médicos, con el objetivo de conocer las temáticas con necesidades de capacitación en cuanto a la atención del paciente grave. Los temas sobre manejo de la vía aérea y ventilación, resucitación cardio-pulmonar-cerebral y el tratamiento del shock, fueron los de mayor relevancia. Se realizó una entrevista a 14 informantes clave y a 3 expertos, se definieron los temas de urgencias y emergencias que son de importancia para los médicos de la APS...


A descriptive research study of the postgraduate education was conducted from June to December 2011. The objective was to identify the learning requirements in the field of basic care to medical urgencies and emergencies of the primary health care physicians who work in Mario Gutierrez Ardaya university polyclinic. The system comprised empirical, theoretical and statistical processing methods. An observational guide was used to evaluate the specific skills of physicians in the care of urgencies and emergencies. Thirty nine physicians answered a questionnaire to detect the topics in which they need training as to the care of the critical patient. The most relevant topics were found to be management of airways and ventilation, cardiopulmonary and cerebral resuscitation, and shock treatment. Fourteen key informants and 3 experts were interviewed, which resulted in the definition of the most important urgency and emergency topics for the primary health care physicians...


Asunto(s)
Humanos , Educación de Postgrado en Medicina , Urgencias Médicas , Aprendizaje , Aprendizaje Basado en Problemas
7.
Artículo en Español | CUMED | ID: cum-65420

RESUMEN

El higroma quístico es el resultado de segmentos del saco linfático yugular que están fuera de sitio o de la falla de los espacios linfáticos para conectar con los principales canales linfáticos y constituye un tumor líquido claro, limpio y transparente; se diagnostica por ecografía en el primer trimestre del embarazo, porque se aprecia una masa que sobresale en la pared posterior o lateral del cuello, su aparición se asocia a cariotipos anormales, por lo cual es indispensable un estudio de cariotipo humano. El higroma quístico está asociado a trisomía ,21, 18, y ,13, entre otras. Se reportó el caso de una paciente con embarazo de ,13,2, semanas, a la cual se le realizó marcador genético, detectándose un feto con una tumoración quística en la región cervical. Se decidió la interrupción de la gestación, mediante el uso de misoprostol, obteniéndose un higroma quístico como resultado anatomopatológico, que reafirmó el diagnóstico ultrasonográfico(AU)


Cystic hygroma is a result of jugular lymph sac segments that are out of place or the failure of the lymphatic spaces to connect with the main lymphatic channels. It is a clear, clean and transparent liquid tumor, diagnosed by ultrasound in the first trimester of pregnancy, for a mass that protrudes in the back or side wall of the neck can be seen, its onset is associated with abnormal karyotypes, which is indispensable for a study of the human karyotype. Cystic hygroma is associated with trisomy ,21, 18, and ,13, among others. A case of a patient with pregnancy of ,13.2, weeks, who underwent genetic marker, detecting a fetus with a cystic tumor in the cervical region was reported. Interruption of pregnancy was decided by using misoprostol, a cystic hygroma was revealed that confirmed the ultrasonographic diagnosis(AU)


Asunto(s)
Humanos , Linfangioma Quístico/cirugía , Linfangioma Quístico/diagnóstico , Linfangioma Quístico , Ultrasonografía , Embarazo , Aborto , Misoprostol
8.
Lab Anim ; 46(4): 280-6, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23097560

RESUMEN

Mice harbouring a humanized liver represent a powerful tool for translating preclinical studies of drug metabolism and pharmacokinetics into humans, as well as the exploitation of basic studies on liver pathophysiology including hepatitis C virus (HCV) infection. Human adult stem cells injected into immunocompetent mice at preimmune stages of development, generate chimeric animals harbouring a liver with relatively discrete foci of human hepatocyte-like cells. In this study, we have evaluated whether similar protocol of xenotransplantation in the presence of selective pressure might lead to a higher human-into-mouse liver repopulation, leading to a relevant improvement of liver function. Human CD34(+)/CD133(+) cells were microinjected into blastocysts from genetically-modified mice committed to develop a lethal hepatopathy, due to the absence of the enzyme fumarylacetoacetate hydrolase (FAH). Following xenotransplantation, mouse survival was followed over time and histochemical evidence of liver chimerism was assessed. The survival expectancy of seven out of 21 intrablastocyst xenotransplanted FAH knockout (Fah-/-) mice was significantly higher as compared with non-xenotransplanted mice. Several nodules of human hepatocyte-like cells were revealed by immunohistochemistry in the liver of rescued mice. Our data positively support the hypothesis that preimmune xenotransplantation of human stem cells into immunocompetent mice harbouring a lethal hepatic disease might lead to a functionally relevant human-mouse liver chimerism and marks a significant advancement towards the establishment of a novel translational preclinical model for liver diseases.


Asunto(s)
Modelos Animales de Enfermedad , Hepatocitos/citología , Hepatocitos/fisiología , Hepatopatías/prevención & control , Hígado/embriología , Células Madre/citología , Trasplante Heterólogo/métodos , Animales , Blastocisto , Diferenciación Celular , Proliferación Celular , Trasplante de Células Madre de Sangre del Cordón Umbilical/métodos , Femenino , Hidrolasas/deficiencia , Hidrolasas/genética , Inmunocompetencia , Inyecciones/métodos , Hígado/citología , Hígado/fisiología , Hepatopatías/embriología , Ratones , Ratones Noqueados , Quimera por Trasplante
9.
Oncol Rep ; 28(2): 682-8, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22665020

RESUMEN

We have recently shown that covalent attachment of the nitric oxide (NO) moiety to the HIV protease inhibitor Saquinavir (Saq) produced a qualitatively new chemical entity, named Saquinavir-NO (Saq-NO), with enhanced anticancer properties and reduced toxicity both in vitro and in vivo. The aim of this study was to address several unanswered questions both on the pharmacological profile of Saq-NO as well as on the in vivo role of NO in the oncogenesis of A375 human melanoma cells. To this end, we have evaluated here the impact of single and combined effects of Saq-NO, Saq, the NO-donor DETA NONOate and the iNOS inhibitor L-NAME on the in vitro as well as in vivo growth of the iNOS positive A375 cells. Our data confirm clear-cut evidence for a strong and powerful anti-melanoma action of Saq-NO that is not duplicable by the combined use of Saq and DETA NONOate. Surprisingly, but also in agreement with the complex and multifaceted role of endogenous NO in A375 cells, both DETA NONOate and L-NAME significantly suppressed the in vivo growth of xenotransplants.


Asunto(s)
Antineoplásicos/farmacología , Melanoma/tratamiento farmacológico , Saquinavir/análogos & derivados , Animales , Procesos de Crecimiento Celular/efectos de los fármacos , Línea Celular Tumoral , Humanos , Masculino , Melanoma/metabolismo , Melanoma/patología , Ratones , Ratones Desnudos , Donantes de Óxido Nítrico/farmacología , Saquinavir/farmacología , Ensayos Antitumor por Modelo de Xenoinjerto
10.
Correo Cient Med Holguín ; 16(3)2012. ilus
Artículo en Español | CUMED | ID: cum-51600

RESUMEN

La anencefalia es un defecto congénito del sistema nervioso central, determinado por la ausencia de los huesos del cráneo y tejido encefálico. El origen es multifactorial y se asocia principalmente con deficiencias de ácido fólico. El diagnóstico se realiza por estudio ecográfico a partir de las 13 semanas de gestación. Se presentó una paciente de 41 años de edad, con antecedentes obstétricos de cuatro embarazos, dos partos y un aborto provocado, con captación intermedia que acude a consulta para marcador genético donde se realizó el diagnóstico ecográfico que evidenció alteración del cráneo, con edad gestacional de 17 semanas. Posterior al diagnóstico se decidió interrupción de la gestación, se obtuvo un producto femenino, con cabeza aplanada, y protrusión ocular bilateral, se envió al departamento de anatomía patológica, el cual envió informe de autopsia fetal que informó feto femenino de 400 gramos y de 15 centímetros de talla, con malformación congénita por defecto del tubo neural anencefalia(AU)...


Anencephaly is a congenital defect of the central nervous system, due to the absence of the bones of the skull and brain tissue. It has multifactorial causes mainly those associated with folic acid deficiencies. Diagnosis is made by ultrasound after ,13, weeks of gestation. A patient of ,41, years of age with obstetric history of four pregnancies, two births and abortion induced, with intermediate catchments was presented in this article. The patient was attended at Genetics consultation, where sonographic diagnosis was made which showed alteration of the skull, with age gestation of ,17, weeks. After the diagnosis was made, the specialists decided to interrupt the pregnancy which was female with flattened head, and bilateral ocular protrusion, sent to the Pathology Department. The autopsy results showed a fetus of ,400, grams and ,15, centimeters size, with congenital defect due to neural tube defect(AU)...


Asunto(s)
Humanos , Femenino , Embarazo , Anencefalia , Deficiencia de Ácido Fólico
11.
Artículo en Español | CUMED | ID: cum-48998

RESUMEN

Se realizó un estudio descriptivo retrospectivo acerca del comportamiento del tratamiento trombolítico en pacientes atendidos en la Unidad de Cuidados Intensivos del Centro de Diagnóstico Integral Higuerot del estado Miranda, Venezuela durante el período 2007-2009. Se tuvieron en cuenta variables como: localización topográfica del infarto del miocardio agudo, total de pacientes trombolisados o no y su estado al egreso, causas de no trombolisis, tiempo transcurrido entre comienzo sintomático y el inicio del tratamiento y las complicaciones. El estudio arrojó que el grupo de edad más afectado fue el de más de 70 años, con el 41,9 por ciento del total de casos, el sexo masculino frente al femenino con el 61,3 por ciento, predominaron los pacientes trombolizados con una razón de 2,44, representando el 70,97 por ciento. La principal causa de no inclusión de pacientes para realizar el proceder, fue por solicitar el servicio con más 12h, lo cual se relaciona con la aparición de complicaciones como arritmias fatales, muerte súbita y reinfarto incidiendo directamente sobre la mortalidad...(AU)


A retrospective descriptive study was performed on thrombolysis treatment behavior at the Intensive Care Unit of the Higuerote Miranda, Venezuela Integral Diagnostic Center during 2007-2009. Topographic location of infarction, total of patients with thrombolysis and the outgoing status, causes of no thrombolysis, the elapsed time between symptomatic beginning and the start of the treatment and the related complications were taken into consideration. This study showed that the most affected age group was the one of 70 years and older 41,9 percent, male sex 61,3 percent and 70,97 percent of the patients with thrombolysis prevailed. The patients that asked for emergency care after 12 hours with this affection was the main cause of no inclusion, which was the cause of some complications such as fatal arrhythmias, sudden death and reinfarction, affecting directly on mortality...(AU)


Asunto(s)
Humanos , Infarto del Miocardio , Mortalidad
13.
J Med Chem ; 48(14): 4547-57, 2005 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-15999993

RESUMEN

Infections caused by hepatitis C virus (HCV) are a significant world health problem for which novel therapies are in urgent demand. Compounds that block replication of subgenomic HCV RNA in liver cells are of interest because of their demonstrated antiviral effect in the clinic. In followup to our recent report that indole-N-acetamides (e.g., 1) are potent allosteric inhibitors of the HCV NS5B polymerase enzyme, we describe here their optimization as cell-based inhibitors. The crystal structure of 1 bound to NS5B was a guide in the design of a two-dimensional compound array that highlighted that formally zwitterionic inhibitors have strong intracellular potency and that pregnane X receptor (PXR) activation (an undesired off-target activity) is linked to a structural feature of the inhibitor. Optimized analogues devoid of PXR activation (e.g., 55, EC(50) = 127 nM) retain strong cell-based efficacy under high serum conditions and show acceptable pharmacokinetics parameters in rat and dog.


Asunto(s)
Acetamidas/síntesis química , Antivirales/síntesis química , Hepacivirus/enzimología , Indoles/síntesis química , ARN Viral/efectos de los fármacos , ARN Polimerasa Dependiente del ARN/antagonistas & inhibidores , Proteínas no Estructurales Virales/antagonistas & inhibidores , Acetamidas/química , Acetamidas/farmacología , Regulación Alostérica , Animales , Antivirales/química , Antivirales/farmacología , Disponibilidad Biológica , Línea Celular Tumoral , Perros , Genoma Viral , Semivida , Hepacivirus/genética , Humanos , Indoles/química , Indoles/farmacología , Modelos Moleculares , Receptor X de Pregnano , ARN Polimerasa Dependiente del ARN/química , Ratas , Ratas Sprague-Dawley , Receptores Citoplasmáticos y Nucleares/agonistas , Receptores de Esteroides/agonistas , Relación Estructura-Actividad , Distribución Tisular , Proteínas no Estructurales Virales/química
14.
Biochem Biophys Res Commun ; 326(1): 66-73, 2005 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-15567153

RESUMEN

It is well established that certain subpopulations of human adult stem cells can generate hepatocyte-like cells when transplanted into adult immunosuppressed mice. In the present study, we wanted to explore whether xeno-transplantation of human cord blood CD34(+) (hCBCD34(+)) cells during pre-immune stages of development in immunocompetent mice might also lead to human-mouse liver chimerism. Freshly isolated hCBCD34(+) cells were xeno-transplanted into non-immunosuppressed mice by both intra-blastocyst and intra-fetal injections. One and four weeks after birth, immunostaining for different human-specific hepatocyte markers: human hepatocyte-specific antigen, human serum albumin, and human alpha-1-antitrypsin indicated the presence of human hepatocyte-like cells in the livers of transplanted animals. Detection of human albumin mRNA further corroborated the development of pre-immune human-mouse chimeras. The current report, besides providing new evidence of the potential of hCBCD34(+) cells to generate human hepatocyte-like cells, suggests novel strategies for generating immunocompetent mice harboring humanized liver.


Asunto(s)
Trasplante de Células Madre de Sangre del Cordón Umbilical/métodos , Hepatocitos/citología , Hepatocitos/fisiología , Hígado/embriología , Células Madre/citología , Trasplante Heterólogo/métodos , Animales , Diferenciación Celular/fisiología , Proliferación Celular , Femenino , Humanos , Inmunocompetencia/fisiología , Inyecciones/métodos , Hígado/citología , Hígado/fisiología , Ratones , Ratones SCID , Embarazo
15.
Cardiovasc Res ; 61(4): 693-704, 2004 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-14985066

RESUMEN

OBJECTIVE: The antiapoptotic effect of p21(Waf1/Cip1/Sdi1) (p21) was examined in human umbilical vein endothelial cells (HUVEC) exposed to laminar shear stress (SS) or to the nitric oxide donor sodium nitroprusside (SNP) and in a mouse model of hindlimb ischemia. METHODS: In vitro: Cells were cultured without serum and in the presence of cobalt chloride to simulate hypoxia for 12 h (T0). Shear stress was applied to endothelial cells for additional 12 h. In vivo: Hindlimb ischemia was realized in mice by femoral artery ligation. SNP was acutely administered by subcutaneous injection or by Alzet osmotic pumps for a longer treatment. RESULTS: At T0, HUVEC were either exposed to SS (15 dyn/cm2/s(-1)), treated with SNP or kept in static condition (ST) for 1-12 h; after additional 12 h in ST, 30-35% of cells still alive at T0 had died. In this condition, both SS and SNP treatments markedly increased p21 levels and reduced apoptosis in HUVEC. Recombinant adenoviruses carrying p21 (AdCMV.p21) or antisense p21 (AdCMV.ASp21) cDNA revealed that AdCMV.p21-infected HUVEC were protected from death while AdCMV.ASp21 reduced SS- and SNP-dependent protection from apoptosis. In mice, apoptosis was detected in endothelial cells of ischemic hindlimbs as early as 8 h after femoral artery ligation. Treatment with SNP enhanced p21 expression and protected ischemic tissue from damage. Remarkably, direct in vivo injection of AdCMV.p21 significantly reduced the number of apoptotic nuclei in the presence of ischemia. CONCLUSIONS: The present study establishes that, under our experimental conditions, (a) p21 plays an important role in SS and nitric oxide antiapoptotic effect in vitro, and (b) p21 gene transfer prevents apoptosis in vitro and in vivo, following acute interruption of blood flow.


Asunto(s)
Ciclinas/farmacología , Células Endoteliales/efectos de los fármacos , Adenoviridae/genética , Animales , Apoptosis/efectos de los fármacos , Células Cultivadas , Inhibidor p21 de las Quinasas Dependientes de la Ciclina , Ciclinas/genética , ADN sin Sentido/administración & dosificación , Vectores Genéticos/administración & dosificación , Miembro Posterior , Humanos , Isquemia/tratamiento farmacológico , Isquemia/metabolismo , Isquemia/patología , Masculino , Ratones , Ratones Endogámicos , Ratones Desnudos , Donantes de Óxido Nítrico/farmacología , Nitroprusiato/farmacología , Estrés Mecánico , Transducción Genética
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