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1.
Biosens Bioelectron ; 106: 105-110, 2018 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-29414075

RESUMO

Rapid, inexpensive and sensitive detection of uropathogenic Escherichia coli (UPEC), a common cause of ascending urinary tract infections (UTIs) including cystitis and pyelonephritis, is critical given the increasing number of cases and its recurrence worldwide. In this paper, we present a label-free nanoplasmonic sensing platform, built with off-the-shelf optical and electronic components, which can detect intact UPEC at concentrations lower than the physiological limit for UTI diagnosis, in real time. The sensing platform consists of a red LED light source, lens assembly, CMOS detector, Raspberry Pi interface in conjugation with a metallic flow-through nanohole array-based sensor. Detection is achieved exploiting nanoplasmonic phenomena from the nanohole arrays through surface plasmon resonance imaging (SPRi) technique. The platform has a bulk sensitivity of 212 pixel intensity unit (PIU)/refractive index unit (RIU), and a resolution in the order of 10-6 RIU. We demonstrate capture and detection of UPEC with a detection limit of ~100 CFU/ml - a concentration well below the threshold limit for UTI diagnosis in clinical samples. We also demonstrate detection of UPEC in spiked human urine samples for two different concentrations of bacteria. This work is particularly relevant for point-of-care applications, especially for regions around the world where accessibility to medical facilities is heavily dependent upon economy, and availability.


Assuntos
Técnicas Biossensoriais , Infecções por Escherichia coli/diagnóstico , Infecções Urinárias/diagnóstico , Escherichia coli Uropatogênica/isolamento & purificação , Infecções por Escherichia coli/microbiologia , Humanos , Limite de Detecção , Nanotecnologia , Infecções Urinárias/microbiologia , Escherichia coli Uropatogênica/patogenicidade
2.
Nat Commun ; 6: 8872, 2015 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-26602832

RESUMO

Little is known about how mitotic cells round against epithelial confinement. Here, we engineer micropillar arrays that subject cells to lateral mechanical confinement similar to that experienced in epithelia. If generating sufficient force to deform the pillars, rounding epithelial (MDCK) cells can create space to divide. However, if mitotic cells cannot create sufficient space, their rounding force, which is generated by actomyosin contraction and hydrostatic pressure, pushes the cell out of confinement. After conducting mitosis in an unperturbed manner, both daughter cells return to the confinement of the pillars. Cells that cannot round against nor escape confinement cannot orient their mitotic spindles and more likely undergo apoptosis. The results highlight how spatially constrained epithelial cells prepare for mitosis: either they are strong enough to round up or they must escape. The ability to escape from confinement and reintegrate after mitosis appears to be a basic property of epithelial cells.


Assuntos
Actomiosina , Células Epiteliais/ultraestrutura , Epitélio/ultraestrutura , Pressão Hidrostática , Mitose , Fuso Acromático/ultraestrutura , Animais , Proliferação de Células , Forma Celular , Tamanho Celular , Sobrevivência Celular , Cães , Células HeLa , Humanos , Células Madin Darby de Rim Canino , Metáfase , Microscopia Confocal , Microscopia Eletrônica de Varredura , Pressão , Estresse Mecânico , Imagem com Lapso de Tempo
3.
Rev. chil. reumatol ; 30(3): 134-137, 2014. ilus
Artigo em Espanhol | LILACS | ID: lil-776851

RESUMO

Temporal arteritis, a large vassel vasculitis, particularly in its classical form, is extremely rare in individuals < 50 years. We report a 38 years old male patient that in the context of fever of unknown origin, and after clinical examination, laboratory and imagin analyses get the diagnosis in mention. Been treated with prednisone at 1 mg/kg/d, the therapeutic response was satisfactory. Today, the patient remains asymptomatic...


La arteritis temporal, una forma de vasculitis de vaso grande, particularmente en su forma clásica, es extremadamente rara en individuos < 50 años. Se reporta el caso de un paciente varón de 38 años que, en contexto de Fiebre de Origen Desconocido luego del estudio clínico, laboratorial y de imagenología, llevó al diagnóstico en mención. Al ser tratado con prednisona en dosis de 1 mg/kg/d, la respuesta terapéutica fue satisfactoria. Actualmente se encuentra asintomático...


Assuntos
Humanos , Masculino , Adulto , Anti-Inflamatórios , Arterite de Células Gigantes/diagnóstico , Arterite de Células Gigantes/tratamento farmacológico , Prednisona/uso terapêutico
4.
Analyst ; 138(5): 1450-8, 2013 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-23344016

RESUMO

Nanohole array-based biosensors integrated with a microfluidic concentration gradient generator were used for imaging detection and quantification of ovarian cancer markers. Calibration curves based on controlled concentrations of the analyte were created using a microfluidic stepped diffusive mixing scheme. Quantification of samples with unknown concentration of analyte was achieved by image-intensity comparison with the calibration curves. The biosensors were first used to detect the immobilization of ovarian cancer marker antibodies, and subsequently applied for the quantification of the ovarian cancer marker r-PAX8 (with a limit of detection of about 5 nM and a dynamic range from 0.25 to 9.0 µg.mL(-1)). The proposed biosensor demonstrated the ability of self-generating calibration curves on-chip in an integrated microfluidic platform, representing a further step towards the development of comprehensive lab-on-chip biomedical diagnostics based on nanohole array technology.


Assuntos
Biomarcadores Tumorais/análise , Técnicas Analíticas Microfluídicas/instrumentação , Neoplasias Ovarianas/diagnóstico , Fatores de Transcrição Box Pareados/análise , Ressonância de Plasmônio de Superfície/instrumentação , Anticorpos Imobilizados/química , Desenho de Equipamento , Feminino , Humanos , Limite de Detecção , Fator de Transcrição PAX8
5.
Arch. cardiol. Méx ; 80(2): 67-76, abr.-jun. 2010. ilus
Artigo em Inglês | LILACS | ID: lil-631962

RESUMO

Objective: To assess the hemocompatible performance of a novel implantable pneumatic ventricular assist device (VAD, Innovamédica, México) in healthy swine. The aim of this pilot study was first, to determine if short-term VAD implantation elicited a remarkable inflammatory response above that expected from surgical trauma; and second, to assess if heparinized or passivated VAD coatings, in combination with systemic anticoagulant or antiaggregant therapies, modified the VAD's hemocompatible performance. Methods: Hemodynamic, physiologic, inflammatory and histological parameters were measured in 27 pigs receiving VAD support for six hours, testing combinations of heparinized or passivated VAD coatings and systemic anticoagulant/ antiaggregant therapies. Mean concentrations of interleukin-1 β (IL-16), interleukin-6 (IL-6), C-reactive protein (CRP), or thrombin-antithrombin III (TAT) complexes (coagulation indicator) were measured from blood. ANOVA statistics were employed. Results: No substantial increases in mean IL-1β, IL-6, CRP, or TAT were obtained during VAD support. Hemodynamic and physiologic parameters were normal. We found no evidence of thromboembolisms or micro-infarctions in heart and lung samples. No major coaguli/deposits were found in VAD compartments. Overall, no remarkable differences in measurements were found using heparinized, passivated, or uncoated VAD, or with systemic anticoagulation, antiaggregant therapy, or no treatment. Conclusions: Our findings demonstrate, firstly, that during the time-period tested, the VAD elicited negligible inflammation above the effects of surgical trauma; and secondly, that little coagulation was observed upon VAD support in any of the cases tested. Contemplating further validation studies, our data indicate that the Innovamédica VAD is a highly hemocompatible system.


Objetivo: Evaluar la hemocompatibilidad de un nuevo dispositivo de asistencia ventricular (DAV, Innovamédica, México) neumático e implantable, en cerdos sanos. En este estudio piloto se propuso determinar primero, si la implantación a corto plazo del DAV suscitaría una respuesta inflamatoria por encima de aquella esperada tras trauma quirúrgico; segundo, evaluar si recubrimientos heparinizados o pasivos del DAV, en combinación con tratamientos sistémicos anticoagulantes o antiplaquetarios, modificarían la hemocompatibilidad del DAV. Métodos: Se midieron parámetros hemodinámicos, fisiológicos, inflamatorios e histológicos en 27 cerdos recibiendo soporte del DAV durante seis horas, evaluando combinaciones de recubrimientos heparinizados y pasivos del DAV, y terapias sistémicas anticoagulantes / antiplaquetarias. Se obtuvieron, a partir de sangre, las concentraciones promedio de interleucina-1 (IL-1β), interleucina-6 (IL-6), proteína C reactiva (PCR) y los complejos trombina-antitrombina III (TAT) (índice de coagulación). Se emplearon análisis estadísticos ANOVA. Resultados: No se observaron incrementos importantes en los niveles promedio de IL-1β, IL-6, PCR, o TAT durante soporte del DAV. Los parámetros hemodinámicos y fisiológicos fueron normales. No existió evidencia alguna de trom-boembolias o micro-infartos en muestras de miocardio y pulmón. No se encontraron coágulos o depósitos mayores en compartimentos del DAV. En general, no se apreciaron diferencias notables de mediciones utilizando dispositivos con recubrimiento heparinizado, pasivo o sin recubrimiento, en conjunto con terapia sistémica anticoagulante, antiplaquetaria o sin ella. Conclusiones: Nuestros hallazgos demuestran, primero, que durante el periodo de medición experimental, el DAV suscitó una respuesta inflamatoria mínima por encima de los efectos de trauma quirúrgico, y; segundo, en todos los casos evaluados, se observaron escasos o inexistentes efectos de coagulación durante soporte ventricular. Contemplando estudios adicionales de validación, nuestros datos indican que el DAV Innovamédica es un sistema altamente hemocompatible.


Assuntos
Animais , Feminino , Masculino , Coração Auxiliar , Teste de Materiais , Coagulação Sanguínea , Hemodinâmica , Coração Auxiliar/efeitos adversos , Inflamação/sangue , Inflamação/etiologia , Projetos Piloto , Complicações Pós-Operatórias/sangue , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/fisiopatologia , Suínos
6.
Anal Chem ; 81(11): 4308-11, 2009 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-19408948

RESUMO

We combine nanofluidics and nanoplasmonics for surface-plasmon resonance (SPR) sensing using flow-through nanohole arrays. The role of surface plasmons on resonant transmission motivates the application of nanohole arrays as surface-based biosensors. Research to date, however, has focused on dead-ended holes, and therefore failed to harness the benefits of nanoconfined transport combined with SPR sensing. The flow-through format enables rapid transport of reactants to the active surface inside the nanoholes, with potential for significantly improved time of analysis and biomarker yield through nanohole sieving. We apply the flow-through method to monitor the formation of a monolayer and the immobilization of an ovarian cancer biomarker specific antibody on the sensing surface in real-time. The flow-through method resulted in a 6-fold improvement in response time as compared to the established flow-over method.


Assuntos
Anticorpos/análise , Técnicas Analíticas Microfluídicas/instrumentação , Nanoestruturas/química , Nanotecnologia/instrumentação , Ressonância de Plasmônio de Superfície/instrumentação , Ressonância de Plasmônio de Superfície/métodos , Anticorpos/imunologia , Biomarcadores Tumorais/análise , Biomarcadores Tumorais/imunologia , Desenho de Equipamento , Feminino , Humanos , Neoplasias Ovarianas/diagnóstico , Neoplasias Ovarianas/imunologia , Ressonância de Plasmônio de Superfície/economia , Fatores de Tempo
7.
In. Amigos contra el SIDA AC. SIDA Hoy 2000. México, D.F, Amigos contra el SIDA AC, 1996. p.125-7.
Monografia em Espanhol | LILACS | ID: lil-277809

RESUMO

La tuberculosis es una enfermedad bacteriana infectocontagiosa crónica causada por mycobacterium tuberculosis. Evidencias epidemiológicas sugieren que la tuberculosis activa acelera la progresión natural de la infección por VIH. Apartados del artículo: Manifestaciones clínicas. Diagnóstico. Tratamiento. Prevención


Assuntos
Síndrome da Imunodeficiência Adquirida , Tuberculose
8.
An. salud ment ; 3(1/2): 17-24, 1987.
Artigo em Espanhol | LILACS, LIPECS | ID: biblio-1106089

RESUMO

El autor lleva a cabo un conjunto de apreciaciones de la enfermedad, entendiéndola como una reacción de la persona en su totalidad frente a estímulos que alteran seriamente su equilibrio. Fundamentando este punto de vista formula, además, apreciaciones de corte histórico.


The author carries out a review of the concept of illnes, considering it as the total reaction of the person to face the stimuli that seriously disturb his equilibrium. Supporting this point of view he also presents historical considerations upon the concept.


Assuntos
Humanos , Doença/história , Fisiologia , Transtornos Mentais
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