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1.
J Appl Stat ; 51(2): 197-215, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38283048

RESUMEN

In this paper, we study the impact of combining profile and network data in solving record de-duplication problems. We also assess the influence of a range of prior distributions on the linkage structure, and explore the use of stochastic gradient Hamiltonian Monte Carlo methods as a faster alternative to obtain samples from the posterior distribution for network parameters. Our methodology is evaluated using the RLdata500 data, which is a popular dataset in the record linkage literature.

2.
Equine Vet J ; 56(3): 456-463, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-37699794

RESUMEN

BACKGROUND: Real-time PCR is the diagnostic technique of choice for the diagnosis and control of equine herpesvirus-1 (EHV-1) in an outbreak setting. The presence of EHV-1 in nasal swabs (NS), whole blood, brain and spinal cord samples has been extensively described; however, there are no reports on the excretion of EHV-1 in urine, its DNA detection patterns, and the role of urine in viral spread during an outbreak. OBJECTIVES: To determine the presence of EHV-1 DNA in urine during natural infection and to compare the DNA detection patterns of EHV-1 in urine, buffy coat (BC) and NS. STUDY DESIGN: Descriptive study of natural infection. METHODS: Urine and whole blood/NS samples were collected at different time points during the hospitalisation of 21 horses involved in two EHV-1 myeloencephalopathy outbreaks in 2021 and 2023 in Spain. Quantitative real-time PCR was performed to compare the viral DNA load between BC-urine samples in 2021 and NS-urine samples in 2023. Sex, age, breed, presence of neurological signs, EHV-1 vaccination status and treatment data were recorded for all horses. RESULTS: A total of 18 hospitalised horses during the 2021 and 2023 outbreaks were positive for EHV-1, and viral DNA was detected in urine samples from a total of 11 horses in both outbreaks. Compared with BC samples, DNA presence was detected in urine samples for longer duration and with slightly higher concentration; however, compared with NS, detection of EHV-1 in urine was similar in duration with lower DNA concentrations. MAIN LIMITATIONS: Limited sample size, different sampling times and protocols (BC vs. NS) in two natural infection outbreak settings. CONCLUSIONS: EHV-1 was detected in the urine from naturally infected horses. Urine should be considered as complimentary to blood and NS in diagnosis of EHV-1 infection.


HISTORIAL: PCR en tiempo real es la técnica diagnostica de preferencia para el diagnóstico y control del herpes virus equino­1 (EHV­1) en una situación de brote. La presencia de EHV­1 en torulas nasales (TN), muestras de sangre entera, cerebro, y medula espinal ha sido descrita en forma extensa; sin embargo, no hay informes de excreción de EHV­1 en orina, la detección del patrón de ADN, y el rol de la orina en la propagación vírica durante un brote. OBJETIVOS: Determinar la presencia de ADN de EHV­1 en muestras de orina durante un brote infeccioso natural y comparar los patrones de detección de ADN de EHV­1 en orina, capa leucocitaria (CL) y TN. DISEÑO DEL ESTUDIO: Estudio prospectivo en una infección natural en caballos hospitalizados. MÉTODOS: Muestras de orina y sangre entera/TN fueron recolectadas a distintos tiempos durante la hospitalización de veintiún caballos involucrados en dos brotes de mielo encefalopatía por EHV­1 en 2021 y 2023 en España. PCR a tiempo real cuantitativo fue llevado a cabo para comparar la carga de ADN viral entre muestras de CL­orina en 2021 y muestras TN­orina en 2023. Sexo, edad, raza, presencia de síntomas neurológicos, estatus de vacunación y datos de tratamiento fueron anotados para todos los caballos. RESULTADOS: Un total de diez y ocho caballos hospitalizados durante los brotes de 2021 y 2023 resultaron positivos a EHV­1, y ADN viral fue detectado en muestras de orina en un total de 11 caballos de ambos brotes. En comparación a muestras de CL, la presencia de AND fue detectado por mas largo tiempo y con una concentración ligeramente mas alta; sin embargo, en comparación a TN, la detección de EHV­1 en orina fue similar en tiempo pero demostró menor concentración de ADN. LIMITACIONES PRINCIPALES: Tamaño de muestra limitado, tiempos de muestreo diferentes, y de protocolos (CL vs. TN) en dos situaciones de brotes naturales. CONCLUSIONES: Se detecto EHV­1 en orina de caballos infectados naturalmente. La recolección, no invasive, de orina debería considerarse como un complemento a las muestras de sangre y TN en el control de caballos infectados en situaciones de brote.


Asunto(s)
Infecciones por Herpesviridae , Herpesvirus Équido 1 , Enfermedades de los Caballos , Caballos/genética , Animales , Herpesvirus Équido 1/genética , ADN Viral/genética , Infecciones por Herpesviridae/diagnóstico , Infecciones por Herpesviridae/epidemiología , Infecciones por Herpesviridae/veterinaria , Reacción en Cadena en Tiempo Real de la Polimerasa/veterinaria , Brotes de Enfermedades/veterinaria , Enfermedades de los Caballos/diagnóstico
4.
Rev Peru Med Exp Salud Publica ; 40(1): 99-104, 2023.
Artículo en Español, Inglés | MEDLINE | ID: mdl-37377244

RESUMEN

We present the case of a young immunocompetent patient, with a history of pulmonary tuberculosis, who attended the hospital with a subacute clinical picture of persistent fever, weight loss, dyspnea and abolition of vesicular murmur. Chest CT scan showed an extensive empyema in the left hemithorax. Samples were taken for detection of common germs. Then, a chest drainage tube was placed and antibiotic therapy started. The MALDI-TOF MS test identified Parvimonas micra, an anaerobic bacterium, commensal to the oral flora, associated with severe periodontitis, but rarely reported in cases of pleural empyema, especially in immunocompetent patients. Gingivitis and pericoronaritis of the third molar were diagnosed during oral evaluation. The patient progressed favorably. Parvimonas micra should be considered as a possible etiological agent in cases of subacute or chronic pleural empyema, in addition to mycobacteria. Tests such as MALDI-TOF MS or 16S rRNA sequencing, chest tube placement, empirical antibiotic coverage and an adequate oral evaluation should be considered in these cases.


Se presenta el caso de un paciente joven inmunocompetente, con antecedente de tuberculosis pulmonar, que acude al hospital por un cuadro clínico subagudo de fiebre persistente, baja de peso, disnea y abolición del murmullo vesicular. La tomografía de tórax mostró un extenso empiema en hemitórax izquierdo. Se le toman muestras para detección de gérmenes comunes y se le colocan un tubo de drenaje torácico y se inicia antibioticoterapia. La prueba de MALDI-TOF MS identificó a Parvimonas micra, una bacteria anaerobia, comensal de la flora oral, asociado a periodontitis severa, escasamente reportado en empiema pleural, especialmente, en personas inmunocompetentes. En la evaluación odontológica se realizó el diagnóstico de gingivitis y pericoronaritis de la tercera molar. El paciente evolucionó favorablemente. Se sugiere que, en casos de empiemas pleurales subagudos o crónicos, se debe considerar, además de las micobacterias, como agente etiológico al Parvimonas micra, y optar por exámenes como MALDI-TOF MS o secuenciamiento del 16S rRNA, colocación de tubo de tórax, cobertura antibiótica empírica y evaluación odontológica.


Asunto(s)
Empiema Pleural , Humanos , ARN Ribosómico 16S , Composición de Base , Análisis de Secuencia de ADN , Filogenia , Empiema Pleural/diagnóstico
5.
Artículo en Inglés | MEDLINE | ID: mdl-36917806

RESUMEN

Background: Untreated human immunodeficiency virus (HIV)-immunosuppressed pediatric patients show high morbidity and mortality from opportunistic infections. Limited cases of hyperferritinemic sepsis have been described in patients with toxoplasmosis. Case report: We describe the case of a 13-year-old female patient with a history of untreated HIV who presented with hyperferritinemic sepsis secondary to Toxoplasma gondii infection and Pneumocystis jirovecci pneumonia. She received ventilatory support, inotropic drugs, treatment for opportunistic germs, and high-dose corticosteroids, but with unfavorable evolution. Conclusions: The global approach to sepsis with elevated ferritin guides to using of therapies aimed at neutralizing the severe inflammatory response. A timely diagnosis would allow prompt treatment and minimize complications.


Introducción: Los pacientes pediátricos inmunodeprimidos por el virus de la inmunodeficiencia humana (VIH) sin tratamiento presentan una elevada morbilidad y mortalidad por infecciones oportunistas. Se han descrito limitados casos de sepsis hiperferritinémica en pacientes con toxoplasmosis. Caso clínico: Se describe el caso de una paciente de 13 años con antecedente de VIH sin tratamiento que presentó sepsis hiperferritinémica secundaria a una infección por Toxoplasma gondii y neumonía por Pneumocystis jirovecci. Recibió soporte ventilatorio, uso de inotrópicos, tratamiento para gérmenes oportunistas y corticoides en altas dosis, pero su evolución fue desfavorable. Conclusiones: El abordaje global de la sepsis con ferritina elevada orienta a utilizar terapias dirigidas a neutralizar la respuesta inflamatoria severa, por lo que un diagnóstico oportuno permitiría iniciar el tratamiento prontamente y minimizar las complicaciones.

6.
Rev. peru. med. exp. salud publica ; 40(1): 99-104, ene. 2023. ilus
Artículo en Español | LILACS | ID: biblio-1442126

RESUMEN

Se presenta el caso de un paciente joven inmunocompetente, con antecedente de tuberculosis pulmonar, que acude al hospital por un cuadro clínico subagudo de fiebre persistente, baja de peso, disnea y abolición del murmullo vesicular. La tomografía de tórax mostró un extenso empiema en hemitórax izquierdo. Se le toman muestras para detección de gérmenes comunes y se le colocan un tubo de drenaje torácico y se inicia antibioticoterapia. La prueba de MALDI-TOF MS identificó a Parvimonas micra, una bacteria anaerobia, comensal de la flora oral, asociado a periodontitis severa, escasamente reportado en empiema pleural, especialmente, en personas inmunocompetentes. En la evaluación odontológica se realizó el diagnóstico de gingivitis y pericoronaritis de la tercera molar. El paciente evolucionó favorablemente. Se sugiere que, en casos de empiemas pleurales subagudos o crónicos, se debe considerar, además de las micobacterias, como agente etiológico al Parvimonas micra, y optar por exámenes como MALDI-TOF MS o secuenciamiento del 16S rRNA, colocación de tubo de tórax, cobertura antibiótica empírica y evaluación odontológica.


We present the case of a young immunocompetent patient, with a history of pulmonary tuberculosis, who attended the hospital with a subacute clinical picture of persistent fever, weight loss, dyspnea and abolition of vesicular murmur. Chest CT scan showed an extensive empyema in the left hemithorax. Samples were taken for detection of common germs. Then, a chest drainage tube was placed and antibiotic therapy started. The MALDI-TOF MS test identified Parvimonas micra, an anaerobic bacterium, commensal to the oral flora, associated with severe periodontitis, but rarely reported in cases of pleural empyema, especially in immunocompetent patients. Gingivitis and pericoronaritis of the third molar were diagnosed during oral evaluation. The patient progressed favorably. Parvimonas micra should be considered as a possible etiological agent in cases of subacute or chronic pleural empyema, in addition to mycobacteria. Tests such as MALDI-TOF MS or 16S rRNA sequencing, chest tube placement, empirical antibiotic coverage and an adequate oral evaluation should be considered in these cases.


Asunto(s)
Humanos , Masculino , Periodontitis
7.
Bol. méd. Hosp. Infant. Méx ; 80(supl.1): 7-11, 2023. graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1513759

RESUMEN

Abstract Background: Untreated human immunodeficiency virus (HIV)-immunosuppressed pediatric patients show high morbidity and mortality from opportunistic infections. Limited cases of hyperferritinemic sepsis have been described in patients with toxoplasmosis. Case report: We describe the case of a 13-year-old female patient with a history of untreated HIV who presented with hyperferritinemic sepsis secondary to Toxoplasma gondii infection and Pneumocystis jirovecci pneumonia. She received ventilatory support, inotropic drugs, treatment for opportunistic germs, and high-dose corticosteroids, but with unfavorable evolution. Conclusions: The global approach to sepsis with elevated ferritin guides to using of therapies aimed at neutralizing the severe inflammatory response. A timely diagnosis would allow prompt treatment and minimize complications.


Resumen Introducción: Los pacientes pediátricos inmunodeprimidos por el virus de la inmunodeficiencia humana (VIH) sin tratamiento presentan una elevada morbilidad y mortalidad por infecciones oportunistas. Se han descrito limitados casos de sepsis hiperferritinémica en pacientes con toxoplasmosis. Caso clínico: Se describe el caso de una paciente de 13 años con antecedente de VIH sin tratamiento que presentó sepsis hiperferritinémica secundaria a una infección por Toxoplasma gondii y neumonía por Pneumocystis jirovecci. Recibió soporte ventilatorio, uso de inotrópicos, tratamiento para gérmenes oportunistas y corticoides en altas dosis, pero su evolución fue desfavorable. Conclusiones: El abordaje global de la sepsis con ferritina elevada orienta a utilizar terapias dirigidas a neutralizar la respuesta inflamatoria severa, por lo que un diagnóstico oportuno permitiría iniciar el tratamiento prontamente y minimizar las complicaciones.

8.
Neurotoxicology ; 87: 70-85, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34481871

RESUMEN

The number of people with dementia worldwide is estimated at 50 million by 2018 and continues to rise mainly due to increasing aging and population growth. Clinical impact of current interventions remains modest and all efforts aimed at the identification of new therapeutic approaches are therefore critical. Previously, we showed that JM-20, a dihydropyridine-benzodiazepine hybrid molecule, protected memory processes against scopolamine-induced cholinergic dysfunction. In order to gain further insight into the therapeutic potential of JM-20 on cognitive decline and Alzheimer's disease (AD) pathology, here we evaluated its neuroprotective effects after chronic aluminum chloride (AlCl3) administration to rats and assessed possible alterations in several types of episodic memory and associated pathological mechanisms. Oral administration of aluminum to rodents recapitulates several neuropathological alterations and cognitive impairment, being considered a convenient tool for testing the efficacy of new therapies for dementia. We used behavioral tasks to test spatial, emotional- associative and novel object recognition memory, as well as molecular, enzymatic and histological assays to evaluate selected biochemical parameters. Our study revealed that JM-20 prevented memory decline alongside the inhibition of AlCl3 -induced oxidative stress, increased AChE activity, TNF-α and pro-apoptotic proteins (like Bax, caspase-3, and 8) levels. JM-20 also protected against neuronal damage in the hippocampus and prefrontal cortex. Our findings expanded our understanding of the ability of JM-20 to preserve memory in rats under neurotoxic conditions and confirm its potential capacity to counteract cognitive impairment and etiological factors of AD by breaking the progression of key steps associated with neurodegeneration.


Asunto(s)
Cloruro de Aluminio/toxicidad , Benzodiazepinas/farmacología , Trastornos de la Memoria/inducido químicamente , Memoria/efectos de los fármacos , Neuronas/efectos de los fármacos , Fármacos Neuroprotectores/farmacología , Niacina/análogos & derivados , Cloruro de Aluminio/antagonistas & inhibidores , Animales , Hipocampo/efectos de los fármacos , Masculino , Aprendizaje por Laberinto/efectos de los fármacos , Trastornos de la Memoria/tratamiento farmacológico , Mitocondrias/efectos de los fármacos , Prueba del Laberinto Acuático de Morris/efectos de los fármacos , Niacina/farmacología , Prueba de Campo Abierto/efectos de los fármacos , Corteza Prefrontal/efectos de los fármacos , Ratas , Ratas Wistar , Prueba de Desempeño de Rotación con Aceleración Constante
9.
Econ Lett ; 199: 109729, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33897073

RESUMEN

Researchers have speculated that the economic and social consequences of COVID19 will harm women's health. This paper tests this claim in the immediate aftermath of Mexico City's COVID-19 stay-at-home order using call-center data. We use an event-study design to track calls for fertility decisions and mental health. Our findings indicate that mental health worsened during the pandemic. Anxiety calls increased substantially, with the effect being most pronounced for those over 45. Calls related to abortion fell in number, while pregnancy calls remained stable. The abortion effect is most pronounced for women between 15 and 30 and those with a high school degree.

10.
Rev. estomatol. Hered ; 30(1): 53-62, ene.-mar. 2020. tab, graf
Artículo en Español | LILACS-Express | LILACS, BBO - Odontología | ID: biblio-1144599

RESUMEN

RESUMEN El Síndrome de Gorlin-Goltz (SGG) es un desorden autosómico dominante, se caracteriza por presentar anomalías esqueléticas, Queratoquistes Odontogénicos (QQOs) múltiples y carcinoma de células basales. Se han realizado estudios comparativos de los QQOs asociados y no asociados al SGG, y se encontró la presencia de mayor número de quistes satélites, proliferaciones sólidas del epitelio, inflamaciones, calcificaciones, más intensa ac-tividad mitótica de las células epiteliales, y mayor recurrencia de los QQOs asociados al SGG. El propósito de este reporte de caso es proporcionar una base objetiva para el manejo terapéutico de los QQOs en pacientes con SGG y una revisión de la literatura científica. Se presenta el caso de una paciente de 63 años, con antecedentes de SGG, sometida a múltiples intervenciones quirúrgicas, incluida exéresis de QQOs en ambos maxilares, que acudió a la consulta nueve años después de su última intervención para un control por la especialidad, donde se evidenció recurrencia de la lesión en maxilar superior derecho, realizándose enucleación, ostectomia periférica y aplicación de solución de Carnoy.


SUMMARY Gorlin-Goltz syndrome (GGS) is an autosomal dominant disorder characterized by skeletal abnormalities, multi-ple Keratocysts Odontogenic (KCOs) and basal cell carcinoma. Comparative studies of the associated KCOs and those not associated with the GGS have been performed, and the presence of a greater number of satellite cysts, solid proliferations of the epithelium, inflammations, calcifications, more intense mitotic activity of the epithelial cells, and greater recurrence of the KCOs associated with the GGS. The purpose of this case report is to provide an objective basis for the therapeutic management of KCOs in patients with GGS and a review of the scientifi c literature. We present the case of a 63-year-old patient, with a history of GGS, who underwent multiple surgical interventions, including exeresis of KCOs in both jaws, who came to the consultation, nine years after her last intervention, for an Odontostomatological check-up, finding KCO recurrent in upper right maxilla, performing enucleation, peripheral ostectomy and application of carnoy solution.

11.
Rev. estomatol. Hered ; 29(3): 224-230, jul.-sep 2019. ilus, tab
Artículo en Español | LILACS-Express | LILACS, BBO - Odontología | ID: biblio-1144578

RESUMEN

El granuloma piógeno es una lesión reactiva en respuesta a diferentes factores locales, su etiología es por traumatismo, caries dental, desequilibrio hormonal, higiene oral deficiente, etc. que produce una proliferación inflamatoria del tejido conectivo, localizada frecuentemente en cavidad oral (encías, lengua, paladar duro, labios y piso de boca) y piel. Clínicamente se presenta como una lesión hiperplásica vascularizada con base pediculada o sésil de tamaño variable y crecimiento lento. Histológicamente presenta proliferación de tejido endotelial a una red vascular con signos de inflamación crónica y tejido de granulación. El presente caso clínico tiene como objetivo identificar las características clínicas, imagenológicas e histopatológicas de Granuloma Piógeno con aspecto tumoral en la cavidad oral en un paciente adulto de la Clínica Dental Docente Cayetano Heredia en el año 2017. Las características clínicas e histopatológicas de granuloma permiten un diagnóstico concreto, dado que su diagnóstico diferencial es similar. Como opciones de tratamiento además de exéresis, tenemos el pulsed-dye laser, inyección intralesional de etanol o corticoides, escleroterapia con tetradecil sulfato de sodio y criocirugía. Las hiperplasias reactivas pueden presentar aspecto tumoral que se descarta con el estudio anatomopatológico. El abordaje y tratamiento requiere un diagnóstico clínico e histopatológico adecuado.


Pyogenic granuloma is a reactive lesion in response to different local factors, including traumatism, caries dental, hormonal imbalance or poor oral hygiene, which produces an inflammatory proliferation of connective tissue. Pyogenic granuloma is frequently located in oral cavity (gums, tongue, hard palate, lips, and floor of mouth) and skin. Clinically, it presents as a vascularized hyperplastic lesion with a slow-growing pedicled or sessile base of variable size and slow growth. Histologically, shows proliferation of endothelial tissue to a vascular network with signs of chronic inflammation and granulation tissue. This case report aims to identify the clinical, imaging and histopathological characteristics of Pyogenic Granuloma with tumor appearance in the oral cavity in an adult patient of the Clínica Dental Docente Cayetano Heredia in 2017. Clinical and histopathological characteristics of granuloma allow a specific diagnosis, given that their differential diagnoses are similar. The treatment options for pyogenic granuloma include excision, laser pulsed-dye, intralesional injection of ethanol or corticosteroids, sclerotherapy with sodium tetradecyl sulfate, and cryosurgery. Reactive hyperplasia may present a tumor appearance that is ruled out by anatomopathological study. Choosing the correct approach and treatment requires a proper clinical and histopathological diagnosis.

12.
Neurol Res ; 41(5): 385-398, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30821663

RESUMEN

OBJECTIVE: JM-20, a novel hybrid synthetic molecule, has been reported to have antioxidant, mitoprotective, anti-excitotoxic, anti-apoptotic and anti-inflammatory properties. However, the neuroprotective effect of JM-20 against memory impairment in preclinical AD-like models has not been analyzed. The aim of this study was to evaluate the potential neuroprotection of JM-20 that preserves essential memory process from cholinergic dysfunction and other molecular damages. METHODS: The effects of JM-20 on scopolamine (1 mg/kg)-induced cognitive disorders were studied. Male Wistar rats (220-230 g) were treated with JM-20 and/or scopolamine, and behavioral tasks were performed. The AChE activity, superoxide dismutase activity, catalase activity, MDA and T-SH level on brain tissue were determined by spectrophotometric methods. Mitochondrial functionality parameters were measured after behavioral tests. Histological analyses on hippocampus and prefrontal cortex were processed with hematoxylin and eosin, and neuronal and axonal damage were determined. RESULTS: The behavioral, biochemical and histopathological studies revealed that oral pre-treatment with JM-20 (8 mg/kg) significantly attenuated the scopolamine-induced memory deficits, mitochondrial malfunction, oxidative stress, and prevented AChE hyperactivity probably due to specific inhibition of AChE enzyme. It was also observed marked histological protection on hippocampal and prefrontal-cortex regions. CONCLUSIONS: The multimodal action of this molecule could mediate the memory protection here observed and suggest that it may modulate different pathological aspects of memory deficits associated with AD in humans.


Asunto(s)
Benzodiazepinas/farmacología , Inhibidores de la Colinesterasa/farmacología , Disfunción Cognitiva/tratamiento farmacológico , Memoria/efectos de los fármacos , Niacina/análogos & derivados , Nootrópicos/farmacología , Acetilcolinesterasa/metabolismo , Animales , Antioxidantes/metabolismo , Encéfalo/efectos de los fármacos , Encéfalo/metabolismo , Encéfalo/patología , Disfunción Cognitiva/metabolismo , Disfunción Cognitiva/patología , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Peroxidación de Lípido/efectos de los fármacos , Peroxidación de Lípido/fisiología , Masculino , Memoria/fisiología , Trastornos de la Memoria/tratamiento farmacológico , Trastornos de la Memoria/metabolismo , Trastornos de la Memoria/patología , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Niacina/farmacología , Distribución Aleatoria , Ratas Wistar , Escopolamina
13.
Bayesian Anal ; 14(4): 1303-1356, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35978607

RESUMEN

Discrete random structures are important tools in Bayesian nonparametrics and the resulting models have proven effective in density estimation, clustering, topic modeling and prediction, among others. In this paper, we consider nested processes and study the dependence structures they induce. Dependence ranges between homogeneity, corresponding to full exchangeability, and maximum heterogeneity, corresponding to (unconditional) independence across samples. The popular nested Dirichlet process is shown to degenerate to the fully exchangeable case when there are ties across samples at the observed or latent level. To overcome this drawback, inherent to nesting general discrete random measures, we introduce a novel class of latent nested processes. These are obtained by adding common and group-specific completely random measures and, then, normalizing to yield dependent random probability measures. We provide results on the partition distributions induced by latent nested processes, and develop a Markov Chain Monte Carlo sampler for Bayesian inferences. A test for distributional homogeneity across groups is obtained as a by-product. The results and their inferential implications are showcased on synthetic and real data.

14.
Neurosci Lett ; 690: 29-35, 2019 01 18.
Artículo en Inglés | MEDLINE | ID: mdl-30304707

RESUMEN

Oxidative stress and mitochondrial dysfunction are two pathophysiological factors often associated with the neurodegenerative process involved in Parkinson's disease (PD). The aim of this study was to investigate the effects of a novel hybrid molecule, named JM-20, in different in vitro and in vivo models of PD induced by rotenone. To perform in vitro studies, SHSY-5Y cells were exposed to rotenone and/or treated with JM-20. To perform in vivo studies male Wistar rats were intoxicated with rotenone (2.5 mg/kg) via intraperitoneal injection and/or treated with JM-20 (40 mg/kg) administered via oral (for 25 days, both treatment). Rats were evaluated for global motor activity by measurement of locomotor activity. In addition, the effects on mortality, general behavior and redox parameters were also investigated. JM-20 protected SHSY-5Y cells against rotenone-induced cytotoxicity, evidenced by a significant diminution of cell death. In in vivo studies, JM-20 prevented rotenone-induced vertical exploration and locomotion frequency reductions, moreover prevented body weight loss and mortality induced by rotenone. It also improved the redox state of rotenone-exposured animals by increasing superoxide dismutase and catalase activities, total tissue-SH levels and decreasing malondialdehyde concentrations. Finally, JM-20 inhibited spontaneous mitochondrial swelling and membrane potential dissipation in isolated rats brain mitochondria. These results demonstrate that JM-20 is a potential neuroprotective agent against rotenone-induced damage in both in vitro and in vivo models, resulting in reduced neuronal oxidative injury and protection of mitochondria from impairment.


Asunto(s)
Benzodiazepinas/farmacología , Fármacos Neuroprotectores/farmacología , Síndromes de Neurotoxicidad/prevención & control , Niacina/análogos & derivados , Rotenona/toxicidad , Animales , Peso Corporal/efectos de los fármacos , Encéfalo/metabolismo , Catalasa/metabolismo , Muerte Celular/efectos de los fármacos , Células Cultivadas , Humanos , Masculino , Mitocondrias/metabolismo , Actividad Motora/efectos de los fármacos , Niacina/farmacología , Estrés Oxidativo/efectos de los fármacos , Ratas , Superóxido Dismutasa/metabolismo
15.
J Comput Graph Stat ; 25(3): 762-788, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-28626348

RESUMEN

Gaussian graphical models are popular for modeling high-dimensional multivariate data with sparse conditional dependencies. A mixture of Gaussian graphical models extends this model to the more realistic scenario where observations come from a heterogenous population composed of a small number of homogeneous sub-groups. In this paper we present a novel stochastic search algorithm for finding the posterior mode of high-dimensional Dirichlet process mixtures of decomposable Gaussian graphical models. Further, we investigate how to harness the massive thread-parallelization capabilities of graphical processing units to accelerate computation. The computational advantages of our algorithms are demonstrated with various simulated data examples in which we compare our stochastic search with a Markov chain Monte Carlo algorithm in moderate dimensional data examples. These experiments show that our stochastic search largely outperforms the Markov chain Monte Carlo algorithm in terms of computing-times and in terms of the quality of the posterior mode discovered. Finally, we analyze a gene expression dataset in which Markov chain Monte Carlo algorithms are too slow to be practically useful.

16.
Arch. cardiol. Méx ; 85(1): 77-79, ene.-mar. 2015. ilus
Artículo en Español | LILACS | ID: lil-746426

RESUMEN

Se presenta el caso de un paciente de 56 años edad que sufre un evento isquémico agudo con arterias coronarias con una importante dilatación en los segmentos proximales izquierdos y una dilatación de hasta 10 mm de diámetro en la coronaria derecha proximal y todo el segmento vertical, compatibles con enfermedad de Kawasaki en fase de secuelas crónicas.


We present a 56 years-old male patient with an acute ischemic episode. The patient showed significant dilation of the left main coronary artery and proximal segments of the left descending artery, as well as a right coronary artery with a 10 mm diameter in the proximal and medial segments. These findings are compatible with a Kawasaki's disease in a chronic phase.


Asunto(s)
Humanos , Masculino , Persona de Mediana Edad , Síndrome Mucocutáneo Linfonodular/diagnóstico
17.
Arch Cardiol Mex ; 85(1): 77-9, 2015.
Artículo en Español | MEDLINE | ID: mdl-25534907

RESUMEN

We present a 56 years-old male patient with an acute ischemic episode. The patient showed significant dilation of the left main coronary artery and proximal segments of the left descending artery, as well as a right coronary artery with a 10mm diameter in the proximal and medial segments. These findings are compatible with a Kawasaki's disease in a chronic phase.


Asunto(s)
Síndrome Mucocutáneo Linfonodular/diagnóstico , Humanos , Masculino , Persona de Mediana Edad
18.
J Stat Plan Inference ; 157-158: 108-120, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25477705

RESUMEN

We discuss fully Bayesian inference in a class of species sampling models that are induced by residual allocation (sometimes called stick-breaking) priors on almost surely discrete random measures. This class provides a generalization of the well-known Ewens sampling formula that allows for additional flexibility while retaining computational tractability. In particular, the procedure is used to derive the exchangeable predictive probability functions associated with the generalized Dirichlet process of Hjort (2000) and the probit stick-breaking prior of Chung and Dunson (2009) and Rodriguez and Dunson (2011). The procedure is illustrated with applications to genetics and nonparametric mixture modeling.

19.
Biostatistics ; 15(2): 353-69, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24174579

RESUMEN

Receiver operating characteristic (ROC) curves are widely used to measure the discriminating power of medical tests and other classification procedures. In many practical applications, the performance of these procedures can depend on covariates such as age, naturally leading to a collection of curves associated with different covariate levels. This paper develops a Bayesian heteroscedastic semiparametric regression model and applies it to the estimation of covariate-dependent ROC curves. More specifically, our approach uses Gaussian process priors to model the conditional mean and conditional variance of the biomarker of interest for each of the populations under study. The model is illustrated through an application to the evaluation of prostate-specific antigen for the diagnosis of prostate cancer, which contrasts the performance of our model against alternative models.


Asunto(s)
Teorema de Bayes , Modelos Estadísticos , Curva ROC , Biomarcadores/sangre , Humanos , Masculino , Valor Predictivo de las Pruebas , Antígeno Prostático Específico/sangre , Neoplasias de la Próstata/sangre , Neoplasias de la Próstata/diagnóstico , Análisis de Regresión
20.
Ann Appl Stat ; 8(4): 2068-2095, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-26925188

RESUMEN

The analysis of the three-dimensional structure of proteins is an important topic in molecular biochemistry. Structure plays a critical role in defining the function of proteins and is more strongly conserved than amino acid sequence over evolutionary timescales. A key challenge is the identification and evaluation of structural similarity between proteins; such analysis can aid in understanding the role of newly discovered proteins and help elucidate evolutionary relationships between organisms. Computational biologists have developed many clever algorithmic techniques for comparing protein structures, however, all are based on heuristic optimization criteria, making statistical interpretation somewhat difficult. Here we present a fully probabilistic framework for pairwise structural alignment of proteins. Our approach has several advantages, including the ability to capture alignment uncertainty and to estimate key "gap" parameters which critically affect the quality of the alignment. We show that several existing alignment methods arise as maximum a posteriori estimates under specific choices of prior distributions and error models. Our probabilistic framework is also easily extended to incorporate additional information, which we demonstrate by including primary sequence information to generate simultaneous sequence-structure alignments that can resolve ambiguities obtained using structure alone. This combined model also provides a natural approach for the difficult task of estimating evolutionary distance based on structural alignments. The model is illustrated by comparison with well-established methods on several challenging protein alignment examples.

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