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We present a comprehensive analysis of the out-of-equilibrium Casimir pressure between two high-[Formula: see text] superconducting plates, each kept at a different temperature. Two interaction regimes can be distinguished. While the zero-point energy dominates in the near field, thermal effects become important at large interplate separations causing a drop in the force's magnitude compared with the usual thermal-equilibrium case. Our detailed calculations highlight the competing role played by propagating and evanescent modes. Moreover, as one of the plates undergoes the superconducting transition, we predict an abrupt change in the force for any plate distance, which has not been previously observed in other systems. The sensitivity of the dielectric function of the high-[Formula: see text] superconductors makes them ideal systems for a possible direct measurement of the out-of-equilibrium Casimir pressure.
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In order to elucidate central elements underlying type 2 diabetes, we constructed a regulatory network model involving 37 components (molecules, receptors, processes, etc.) associated to signaling pathways of pancreatic beta-cells. In a first approximation, the network topology was described by Boolean rules whose interacting dynamics predicted stationary patterns broadly classified as health, metabolic syndrome, and diabetes stages. A subsequent approximation based on a continuous logic analysis allowed us to characterize the progression of the disease as transitions between these states associated to alterations of cell homeostasis due to exhaustion or exacerbation of specific regulatory signals. The method allowed the identification of key transcription factors involved in metabolic stress as essential for the progression of the disease. Integration of the present analysis with existent mathematical models designed to yield accurate account of experimental data in human or animal essays leads to reliable predictions for beta-cell mass, insulinemia, glycemia, and glycosylated hemoglobin in diabetic fatty rats.
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Diabetes Mellitus Tipo 2 , Células Secretoras de Insulina , Animales , Redes Reguladoras de Genes , Homeostasis , Humanos , Ratas , Transducción de SeñalRESUMEN
Near-field radiative heat transfer (NFRHT) management can be achieved using high-temperature superconductors. In this work, we present a theoretical study of the radiative heat transfer between two [Formula: see text] (YBCO) slabs in three different scenarios: Both slabs either in the normal or superconducting state, and only one of them below the superconductor critical temperature [Formula: see text]. The radiative heat transfer is calculated using Rytov's theory of fluctuating electrodynamics, while a two-fluid model describes the dielectric function of the superconducting materials. Our main result is the significant suppression of the NFRHT when one or both of the slabs are superconducting, which is explained in terms of the detailed balance of the charge carriers density together with the sudden reduction of the free electron scattering rate. A critical and unique feature affecting the radiative heat transfer between high-temperature superconductors is the large damping of the mid-infrared carriers which screens the surface plasmon excitation.
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El tumor desmoides es un tumor benigno raro, de origen fibroblastico no inflamatorio, algunas veces referido como fibromatosis no agresiva. Su etiología aún no está completamente clara, sin embargo, se asocia habitualmente a trauma previo y/o procedimientos quirúrgicos. La ubicación más frecuente es abdominal, el cual posee características imagenologicas claras, al igual que su presentación musculo esquelética plantar. La presentación fuera de estos lugares es infrecuente y difícil de diagnosticar. Presentamos un caso de un tumor desmoides cervical que genero un gran desafío diagnóstico, identificando sus claves diagnósticas y realizando una revisión de la bibliografía al respecto para esta ubicación.
Desmoid tumours are a rare benign tumour of fibroblastic non inflammatory origin, sometimes referred as non aggressive fibromatosis.The etiology is not yet completely clear, however, it is usually associated with previous trauma and / or surgical procedures. The most frequent location is in the abdomen, which has typical images characteristics, as well as its skeletal muscle presentation at the plantar level. The presentation outside these places is infrequent and difficult to diagnose. We present a case of a cervical desmoid tumour that generated a great diagnostic challenge, identifying its key imaging characteristics and performing a literature review of the bibliography regarding this location.
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Humanos , Masculino , Adulto , Fibroma/cirugía , Fibroma/diagnóstico por imagen , Neoplasias de Cabeza y Cuello/cirugía , Neoplasias de Cabeza y Cuello/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Fibroma/patología , Neoplasias de Cabeza y Cuello/patologíaAsunto(s)
Osteosarcoma/diagnóstico , Neoplasias Cutáneas/diagnóstico , Piel/patología , Adulto , Biopsia , Humanos , Masculino , Osteosarcoma/patología , Osteosarcoma/cirugía , Piel/diagnóstico por imagen , Neoplasias Cutáneas/patología , Neoplasias Cutáneas/cirugía , Pared Torácica , Tomografía Computarizada por Rayos X , Resultado del TratamientoAsunto(s)
Leprostáticos/uso terapéutico , Lepra/diagnóstico , Mycobacterium leprae/aislamiento & purificación , Parestesia/etiología , Piel/patología , Anciano , Biopsia , Quimioterapia Combinada , Femenino , Humanos , Lepra/complicaciones , Lepra/tratamiento farmacológico , Lepra/microbiología , México , Parestesia/tratamiento farmacológico , Piel/microbiología , Texas , Resultado del TratamientoAsunto(s)
Alopecia/genética , Expresión Génica , Prostaglandina-E Sintasas/genética , Receptores Inmunológicos/genética , Receptores de Prostaglandina/genética , Adulto , Estudios de Casos y Controles , Femenino , Humanos , Oxidorreductasas Intramoleculares/genética , Masculino , Persona de Mediana Edad , Factores Sexuales , Piel , Adulto JovenRESUMEN
Introducción:El principal mecanismo patogénico que subyace la génesis y desarrollo de enfermedades del sistema circulatorio es la aterosclerosis. Es un proceso patológico complejo y progresivo de la pared arterial que afecta especialmente a las arterias coronarias, cerebrales y periféricas.Actualmente se habla sobre "La hipótesis infecciosa de la aterosclerosis". La infección por Helicobacter pyloriha sido una de las más investigadas a nivel global. Objetivo:Identificar H. pyloria partir de lesiones ateroscleróticas de pacientes que acuden a los servicios de cirugía cardiovascular y angiología de la ciudad de Barranquilla.Métodos:Se realizó un estudio descriptivo de corte transversal.En una muestra de 102 participantes.Los ateromas fueron tomados por personal experto en endarterectomía y disección de vasos sanguíneos. Los especímenes fueron embebidos en solución formaldehído al 4%.Se realizó extracción de ADN a partir de ateromas. El diagnóstico molecular de H. Pylorise realizó por PCR ANIDADA, evidenciando un fragmento de 120 pb posterior a la electroforesis en gel de agarosa al 3,5% en TBE 0,5X. Resultados:Se obtuvieron 102 muestras de ateromas. Una muestra resultó positiva para H. pylori(Muestra #14; 1/102).El tejido aterosclerótico fue obtenido a partir de arteria coronaria derecha. Conclusión: La hipótesis infecciosa de la aterosclerosis ha sido uno de los principales temas de investigación a nivel mundial en las últimas décadas. La infección por H. pylori es un factorde riesgo, sin embargo, varios estudios son necesarios para poder concluir de manera más precisa.
Introduction:The main pathogenic mechanism underlying the genesis and development of diseases of the circulatory system is atherosclerosis. It is a complex and progressive pathological process of the arterial wall that affects especially the coronary, cerebral and peripheral arteries. Currently, there is talk about "The infectious hypothesis of atherosclerosis". Helicobacter pyloriinfection has been one of the most researched worldwide. Objective:To identify H. pylori from atherosclerotic lesions of patients who attend the cardiovascular and angiology services of the city of Barranquilla. Methods:A descriptive cross-sectional study was carried out. In a sample of 102 participants. The atheromas were taken by expert personnel in endarterectomy and dissection of blood vessels. The specimens were embedded in 4% formaldehyde solution. DNA extraction was performed from atheromas. The molecular diagnosis of H. pyloriwas performed by ANIDADA PCR, evidencing a 120 bp fragment after electrophoresis in a 3.5% agarose gel in 0.5X TBE. Results:102 samples of atheromas were obtained. One sample was positive for H. pylori (Sample # 14, 1/102). The atherosclerotic tissue was obtained from the right coronary artery. Conclusion:The infectious hypothesis of atherosclerosis has been one of the main research topics worldwide in recent decades. H. pyloriinfection is a risk factor, however, several studies are necessary to be able to conclude more accurately
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Humanos , Química Ambiental , Sistema Cardiovascular , CorazónRESUMEN
Introducción:Las enfermedades del sistema circulatorio representan uno de los mayores problemas de salud pública a nivel mundial, nacional y regional. Elmecanismo patogénico que subyace esta patología es la aterosclerosis. Existenvarios factores que favorecen la etiopatogeniade la lesión aterosclerótica.Las infecciones, juegan un papel importante.La infección por el Virus del Herpes Simplexse ha considerado como un factor de riesgo emergente. Objetivo:Realizar diagnósticomolecular de infección porVirus Herpes Simplex tipo 1 y tipo 2en tejido aterosclerótico humano.Método:Se realizó extracción de ADN viral a partir de ateromas usando el kit comercial PureGenomeTM Tissue DNA Extraction.La amplificación delmaterial genético viralse realizó porPCR en tiempo real (qPCR) con el kit comercial "Human Herpes Virus 2 (Herpes simplex type 2)UL36 region genesig Standard Kit y Human Herpes Virus 1 (Herpes simplex type 1) Capsid assembly and DNA maturation gene. Genesig Standard Kit".Resultados:En total se obtuvieron 102 muestras de ateromas, extraídas de diferentes fuentes anatómicas. Tresmuestras resultaronpositivas para VHS tipo 1(3/102).Ninguna muestra evidenció material genético para VHS tipo 2 (0/102). Conclusión:La etiopatogenia de la aterosclerosis es un proceso altamente complejo.Los virus juegan un papel importante, en especial la infección por Virus del herpes simplex tipo 1. La infección por estevirus genera cambios a nivel de las células vasculares y no vasculares, favoreciendo el acumulo de lipoproteínas de baja densidad químicamente oxidadas, importantespara la aterogénesis
Introduction:Diseases of the circulatory system represent one of the greatest public health problems worldwide, nationally and regionally. The pathogenic mechanism that underlies this pathology is atherosclerosis. There are several factors that favor the etiopathogeny of the atherosclerotic lesion. Infections play an important role. Infection with Herpes Simplex Virus has been considered as an emerging risk factor. Objective: To perform molecular diagnosis of infection by Herpes Simplex virus type 1 and type 2 in human atherosclerotic tissue. Method:Viral DNA extraction was performed from atheromas using the commercial PureGenomeTM Tissue DNA Extraction kit. The amplification of the viral genetic material was performed by real-time PCR (qPCR) with the commercial kit "Human Herpes Virus 2 (Herpes simplex type 2) UL36 region genesig Standard Kit and Human Herpes Virus 1 (Herpes simplex type 1) Capsid assembly and DNA maturation gene Genesig Standard Kit ". Results:A total of 102 samples of atheromas were obtained, extracted from different anatomicalsources. Three samples were positive for HSV type 1 (3/102). No sample showed genetic material for HSV type 2 (0/102). Conclusion:The etiopathogenesis of atherosclerosis is a highly complex process. Viruses play an important role, especially the infection by Herpes simplex virus type 1. The infection by this virus generates changes at the level of vascular and non-vascular cells, favoring the accumulation of chemically oxidized low density lipoproteins, important for the atherogenesis
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Humanos , Virus , Herpes Zóster , Biología MolecularRESUMEN
Sweet syndrome is the most representative entity of febrile neutrophilic dermatoses. It typically presents in patients with pirexya, neutrophilia, painful tender erytomatous papules, nodules and plaques often distributed asymmetrically. Frequent sites include the face, neck and upper extremities. Affected sites show a characteristical neutrophilic infiltrate in the upper dermis. Its etiology remains elucidated, but it seems that can be mediated by a hypersensitivity reaction in which cytokines, followed by infiltration of neutrophils, may be involved. Systemic corticosteroids are the first-line of treatment in most cases. We present a concise review of the pathogenesis, classification, diagnosis and treatment update of this entity.
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Síndrome de Sweet , Algoritmos , Humanos , Síndrome de Sweet/diagnóstico , Síndrome de Sweet/terapiaRESUMEN
The outbreak of highly pathogenic avian influenza (HPAI) H5N2 in Mexico in 1994 led to a clear increase in biosecurity measures and improvement of intensive poultry production systems. The control and eradication measures implemented were based on active surveillance, disease detection, depopulation of infected farms and prevention of possible contacts (identified by epidemiological investigations), improvement of biosecurity measures, and restriction of the movement of live birds, poultry products, by-products and infected material. In addition, Mexico introduced a massive vaccination programme, which resulted in the eradication of HPAI in a relatively short time in two affected areas that had a high density of commercial poultry.
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Subtipo H5N2 del Virus de la Influenza A , Gripe Aviar/epidemiología , Animales , Control de Enfermedades Transmisibles/economía , Control de Enfermedades Transmisibles/métodos , Urgencias Médicas/economía , Urgencias Médicas/epidemiología , Urgencias Médicas/veterinaria , Humanos , Subtipo H5N2 del Virus de la Influenza A/inmunología , Subtipo H5N2 del Virus de la Influenza A/patogenicidad , Gripe Aviar/economía , Gripe Aviar/prevención & control , Gripe Humana/prevención & control , México/epidemiología , Aves de Corral , Vacunación/economía , Vacunación/veterinaria , Vacunas/clasificaciónRESUMEN
The outbreaks of highly pathogenic avian influenza (HPAI) in Canada in 1966, the USA in 1984 and Mexico in 1994 led to a clear increase in biosecurity measures and improved intensive poultry production systems. In the past 12 years (1994-2006), there have been four outbreaks of HPAI on the American continent: in Mexico in 1994 (H5N2), in Chile in 2002 (H7N3), in the USA in 2004 (H5N2) and in Canada in 2004 (H7N3). In all cases, the control and eradication measures were based on prompt detection, depopulation of infected farms and epidemiological contacts, increased biosecurity measures and control of the movement of live poultry and their products, by-products and infected material. In Mexico, in addition to the aforementioned measures, the use of massive vaccination allowed eradication of HPAI in a relatively short time in two affected areas of high-density commercial poultry.
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Control de Enfermedades Transmisibles/métodos , Subtipo H5N1 del Virus de la Influenza A , Gripe Aviar/epidemiología , Gripe Aviar/prevención & control , Agricultura , Animales , Aves , Chile/epidemiología , Comercio , Brotes de Enfermedades , Gripe Aviar/virología , Cooperación Internacional , América del Norte/epidemiologíaRESUMEN
Syncytia formation in HIV infections is driven by the virus fusion-active molecules (Env) interacting with membrane components of hosts cells. HIV-syncytia are usually interpreted as pathogenic entities and although they may potentially vary in size, numbers and types of constituent cells, little is known about the extent and significance of their diversity. Here, we describe numerically the cell population dynamics and the diversity of syncytia produced in the in vitro cell-fusion between two Jurkat T cell lines, one CD4(+) and the other Env(+). Cell-fusion partners were differentially stained with the lipophilic DiI and DiO, or with the cytoplasmic CMFDA and CMTMR tracers and syncytia showing double fluorescence were counted in a flow cytometer. The total number of syncytia formed, their size, cellular complexity and ratio of CD4(+)/Env(+) cells recruited, varied significantly in relation with time of reaction and initial proportions of fusion partners. The considerable structural diversity of syncytia formed, in so limited an in vitro cell fusion reaction, suggests that a greater heterogeneity may be formed in the natural course of disease. Identification of the main determinants of syncytia diversity allows for a detailed study of the relation between the syncytia structure and function.
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Antígenos CD4/metabolismo , Células Gigantes/citología , VIH-1/química , Proteínas del Envoltorio Viral/metabolismo , Recuento de Células , Fusión Celular , Tamaño de la Célula , Infecciones por VIH/virología , VIH-1/fisiología , Humanos , Células Jurkat/fisiologíaRESUMEN
In December 1994, a highly pathogenic (HP) avian influenza (AI) outbreak occurred in Mexico, caused by the subtype H5N2, affecting two main regions of egg and poultry-meat production. At that time, governmental actions included immediate stamping out of the affected flocks, disinfection of affected premises, quarantine measures in the region, strict movement controls on poultry and their products and vaccination. With these policies, the disease was eradicated in a relatively short time. The last case of HPAI was detected in June 1995 and the country was declared as free of HPAI virus in January 1996 to the World Animal Health Organisation (OIE). Since then, Mexico has maintained a control programme against low pathogenic (LP) AI virus that is based on a zoning classification, movement controls and other strategies.
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Brotes de Enfermedades/veterinaria , Subtipo H5N2 del Virus de la Influenza A/inmunología , Gripe Aviar/epidemiología , Gripe Aviar/prevención & control , Animales , Brotes de Enfermedades/prevención & control , México/epidemiología , Aves de Corral , Vacunación/métodosRESUMEN
Se realizó un estudio retrospectivo en los últimos 7 años, período comprendido entre junio de 1995 y junio de 2002, donde analizamos los pacientes que se presentaron en nuestro servicio con cáncer de pene, evaluando edad promedio de presentación, tipo histológico más frecuente, relación con patologías pre-malignas, presencia de adenopatías al momento del diagnóstico de la lesión primaria, la evolución y presencia de adenopatías durante el seguimiento y su conducta terapéutica. La edad promedio de 57,7 años teniendo en cuenta que más de la mitad de los casos (61,1 porciento) se presentaron en el grupo etario comprendido entre los 51 y 70 años de edad. Se realizaron 12 (67 porciento) penectomías parciales y 6 (33 porciento)penectomías totales. La histología reveló en todos los casos Carcinoma Epidermoide. En 3 casos (16 por ciento), se asoció con H.P.V. y en 1 caso (5 por ciento) con Balanitis Xerótica Obliterante. Tres pacientes presentaron adenopatías al momento del diagnóstico de la lesión peneana y por lo que, tras persistir las mismas pese al tratamiento ATB, se realizó linfadenectomía inguinal bilateral en 2 casos. Las complicaciones posteriores a las linfadenectomías, en orden decreciente de frecuencia fueron linforrea en 6 casos (85,4 por ciento), infección de la herida en 4 casos (57,1 por ciento), edemas de MMII en 3 casos (42,8 porciento) y necrosis de la piel en 2 casos (28,5 porciento. En resumen, de los 18 pacientes que fueron evaluados en este estudio, 9 pacientes (50 por ciento) en la actualidad se encuentran bajo control, de los cuales 8 (44,5 por ciento) se encuentran libre de enfermedad, mmientras que el paciente restante (5,5 por ciento) presenta enfermedad avanzada. Encontramos que la edad promedio, el tipo histológico más frecuente y la concurrencia de cáncer de pene y fimosis, coincide con los datos de la bibliografía mundial. Con respecto a los pacientes sin adenopatías en el momento de la presentación del cáncer, nuestra conducta es el control periódico de los mismos, sin la realización de linfadenectomías, hasta la aparición de ganglios sospechosos, ya que consideramos que la frecuencia de las complicaciones luego de la gran disección ganglionar es alta (30-50 porciento)sin haber informes fehacientes que indiquen una reducción evidente en las tasas de supervivencia a los 5 años.
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Humanos , Masculino , Persona de Mediana Edad , Carcinoma de Células Escamosas/epidemiología , Neoplasias del Pene , Procedimientos Quirúrgicos Urológicos Masculinos/estadística & datos numéricos , Edad de Inicio , Carcinoma de Células Escamosas/cirugía , Estadísticas Hospitalarias , Hospitales Provinciales/estadística & datos numéricos , Escisión del Ganglio Linfático , Neoplasias del Pene , Estudios RetrospectivosRESUMEN
We propose an experimental procedure to investigate possible mechanisms for radiation emission in sonoluminescence. Our analysis is based on Mie's theory of light scattering for a coated sphere in an external medium. Depending on the physical mechanism responsible of sonoluminescence, the dielectric constant of the hot spot changes. As a case study we consider the problem of the detection of an inner plasma core in sonoluminescent bubbles. Our results show that polarization measurements of scattered light should discern the presence of a plasma provided that light detectors are fast enough. Extensions to other emission mechanisms are briefly discussed.
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The geographic distribution of Plasmodium vivax circumsporozoite protein phenotypes from patient blood used to infect colonized Anopheles albimanus and An. pseudopunctipennis was investigated in southern Mexico. Parasite phenotype types were determined in blood samples by a polymerase chain reaction and oligoprobe hybridization or by immunofluorescent assay of sporozoites. The proportion of infected mosquitoes and the number of oocysts per mosquito confirmed previous in vitro observations indicating that An. albimanus is more susceptible to VK210 and that An. pseudopunctipennis is more susceptible to VK247. All patients living on the coast were infected with VK210 and most patients living above 170 meters above sea level had VK247. Both phenotypes infected patients from intermediate altitudes. These results concur with the distribution of the anophelines, indicating that An. albimanus is the main vector of the phenotype VK210, but that An. pseudopunctipennis transmits both phenotypes. These conditions have direct implications on parasite transmission rates and malaria epidemiology in Mexico.
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Anopheles/parasitología , Insectos Vectores/parasitología , Malaria Vivax/epidemiología , Plasmodium vivax/clasificación , Altitud , Animales , Anticuerpos Monoclonales , Anticuerpos Antiprotozoarios/análisis , Antimaláricos/uso terapéutico , Cloroquina/uso terapéutico , Cartilla de ADN/química , ADN Protozoario/química , ADN Protozoario/aislamiento & purificación , Femenino , Fluoroinmunoensayo , Humanos , Malaria Vivax/sangre , Malaria Vivax/parasitología , Masculino , México/epidemiología , Hibridación de Ácido Nucleico , Fenotipo , Plasmodium vivax/química , Plasmodium vivax/genética , Reacción en Cadena de la Polimerasa , Prevalencia , Primaquina/uso terapéutico , Recurrencia , Análisis de RegresiónRESUMEN
The susceptibilities to coindigenous Plasmodium vivax of colonized Anopheles albimanus and Anopheles pseudopunctipennis from southern Mexico were investigated by simultaneous feeding with infected blood obtained from patients. The genes encoding circumsporozoite protein variant types (VK210 and VK247) in blood samples were determined by PCR and oligonucleotide probe hybridization. A. albimanus was more susceptible to VK210, and A. pseudopunctipennis was more susceptible to VK247.