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1.
Breast Cancer Res ; 23(1): 72, 2021 07 12.
Artículo en Inglés | MEDLINE | ID: mdl-34253233

RESUMEN

BACKGROUND: Re-excision due to positive margins following breast-conserving surgery (BCS) negatively affects patient outcomes and healthcare costs. The inability to visualize margin involvement is a significant challenge in BCS. 5-Aminolevulinic acid hydrochloride (5-ALA HCl), a non-fluorescent oral prodrug, causes intracellular accumulation of fluorescent porphyrins in cancer cells. This single-center Phase II randomized controlled trial evaluated the safety, feasibility, and diagnostic accuracy of a prototype handheld fluorescence imaging device plus 5-ALA for intraoperative visualization of invasive breast carcinomas during BCS. METHODS: Fifty-four patients were enrolled and randomized to receive no 5-ALA or oral 5-ALA HCl (15 or 30 mg/kg). Forty-five patients (n = 15/group) were included in the analysis. Fluorescence imaging of the excised surgical specimen was performed, and biopsies were collected from within and outside the clinically demarcated tumor border of the gross specimen for blinded histopathology. RESULTS: In the absence of 5-ALA, tissue autofluorescence imaging lacked tumor-specific fluorescent contrast. Both 5-ALA doses caused bright red tumor fluorescence, with improved visualization of tumor contrasted against normal tissue autofluorescence. In the 15 mg/kg 5-ALA group, the positive predictive value (PPV) for detecting breast cancer inside and outside the grossly demarcated tumor border was 100.0% and 55.6%, respectively. In the 30 mg/kg 5-ALA group, the PPV was 100.0% and 50.0% inside and outside the demarcated tumor border, respectively. No adverse events were observed, and clinical feasibility of this imaging device-5-ALA combination approach was confirmed. CONCLUSIONS: This is the first known clinical report of visualization of 5-ALA-induced fluorescence in invasive breast carcinoma using a real-time handheld intraoperative fluorescence imaging device. TRIAL REGISTRATION: Clinicaltrials.gov identifier NCT01837225 . Registered 23 April 2013.


Asunto(s)
Ácido Aminolevulínico/uso terapéutico , Neoplasias de la Mama/diagnóstico por imagen , Imagen Óptica/métodos , Adulto , Anciano , Anciano de 80 o más Años , Biopsia , Neoplasias de la Mama/patología , Neoplasias de la Mama/cirugía , Medios de Contraste/uso terapéutico , Femenino , Fluorescencia , Humanos , Cuidados Intraoperatorios , Márgenes de Escisión , Mastectomía Segmentaria , Persona de Mediana Edad , Imagen Óptica/instrumentación , Valor Predictivo de las Pruebas , Cirugía Asistida por Computador
2.
Int Wound J ; 13(4): 449-53, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25907362

RESUMEN

Chronic wounds are a significant burden to global patient and health care infrastructures, and there is a need for better methods of early wound diagnosis and treatment. Traditional diagnosis of chronic wound infection by pathogenic bacteria, using clinical signs and symptoms, is based on visual inspection under white light and microbiological sampling (e.g. swabbing and/or biopsy) of the wound, which are subjective and suboptimal. Diagnosing microbial infection based on traditional clinical signs and symptoms in wounds of asymptomatic patients is especially challenging at the bedside. Bacteria are invisible to the unaided eye and wound sampling for diagnostic testing can cause unacceptable delays in diagnosis and treatment. To address this problem, we developed a new prototype handheld, portable fluorescence imaging device that enables non-contact, real-time, high-resolution visualisation of pathogenic bacteria and tissues in wounds. Herein, we report the clinical use of this imaging device in detecting subsurface heavy bacterial load and subclinical local infection in an asymptomatic 50-year-old patient with a non-healing diabetic foot ulcer.


Asunto(s)
Infección de Heridas , Bacterias , Carga Bacteriana , Pie Diabético , Humanos , Persona de Mediana Edad
3.
Soft Robot ; 10(3): 556-567, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36854140

RESUMEN

Robot grippers that lack physical compliance have a difficult time dealing with uncertainty, such as fragile objects that may not have well-defined shapes. Existing soft robotic grippers require a large empty workspace for their actuated fingers to curl around the objects of interest, limiting their performance in clutter. This article presents a three-dimensional structure that exhibits negative stiffness in every bending direction used as fingers in a class of soft robotic grippers. Our approach exploits a compliant mechanism in a conical shape such that a transverse external contact force causes the fingers to bend toward the contact, enabling passive conformation for an adaptive grasp, even in clutter. We show analytically and experimentally that the proposed fingers have a negative bending response and that they conform to objects of various diameters. We demonstrate a soft robotic gripper with three self-conforming fingers performing the following: (1) fingertip grasping, (2) power grasping, and (3) semipassive grasping in clutter. Grasping experiments focus on picking fruits, which exemplify delicate objects with unmodeled shapes with significant variation. The experimental results reveal the ability of the self-conforming structure to smoothly envelope a broad range of objects and demonstrate a 100% grasp success rate in the experiments performed. The proposed passively conforming fingers enable picking of complex and unknown geometries without disturbing nearby objects in clutter and without the need for complex grasping algorithms. The proposed structures can be tailored to deform in desired ways, enabling a robust strategy for the engineering of physical compliance for adaptive soft structures.


Asunto(s)
Robótica , Robótica/métodos , Diseño de Equipo , Dedos/fisiología , Fenómenos Mecánicos , Fuerza de la Mano/fisiología
4.
New Phytol ; 187(4): 1034-1047, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20646220

RESUMEN

*ToxA, a host-selective toxin of wheat, can be detected within ToxA-sensitive mesophyll cells, where it localizes to chloroplasts and induces necrosis. Interaction of ToxA with the chloroplast-localized protein ToxABP1 has been implicated in this process. Therefore, we hypothesized that silencing of ToxABP1 in wheat would lead to a necrotic phenotype. Also, because ToxABP1 is highly conserved in plants, internal expression of ToxA in plants that do not normally internalize ToxA should result in cell death. *Reduction of ToxABP1 expression was achieved using Barley stripe mosaic virus (BSMV)-mediated, viral-induced gene silencing. The BSMV system was modified for use as an internal expression vector for ToxA in monocots. Agrobacterium-mediated expression of ToxA in a dicot (tobacco-Nicotiana benthamiana) was also performed. *Viral-induced gene silencing of ToxABP1 partially recapitulates the phenotype of ToxA treatment and wheat plants with reduced ToxABP1 also have reduced sensitivity to ToxA. When ToxA is expressed in ToxA-insensitive wheat, barley (Hordeum vulgare) and tobacco, cell death ensues. *ToxA accumulation in any chloroplast-containing cell is likely to result in cell death. Our data indicate that the ToxA-ToxABP1 interaction alters ToxABP1 function. This interaction is a critical, although not exclusive, component of the ToxA-induced cell death cascade.


Asunto(s)
Ascomicetos/patogenicidad , Proteínas Fúngicas/metabolismo , Genes Fúngicos , Genes de Plantas , Micotoxinas/metabolismo , Enfermedades de las Plantas/microbiología , Proteínas de Plantas/metabolismo , Ascomicetos/genética , Muerte Celular , Proteínas Fúngicas/genética , Expresión Génica , Silenciador del Gen , Hordeum/genética , Hordeum/metabolismo , Interacciones Huésped-Patógeno/fisiología , Virus del Mosaico , Micotoxinas/genética , Enfermedades de las Plantas/genética , Proteínas de Plantas/genética , Nicotiana/genética , Nicotiana/metabolismo , Triticum/genética , Triticum/metabolismo
5.
Genome ; 53(1): 1-13, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20130744

RESUMEN

The grass species Brachypodium distachyon (hereafter, Brachypodium) has been adopted as a model system for grasses. Here, we describe the development of a genetic linkage map of Brachypodium. The genetic linkage map was developed with an F2 population from a cross between the diploid Brachypodium lines Bd3-1 and Bd21. The map was populated with polymorphic simple sequence repeat (SSR) markers from Brachypodium expressed sequence tag (EST) and bacterial artificial chromosome (BAC) end sequences and conserved orthologous sequence (COS) markers from other grass species. The map is 1386 cM in length and consists of 139 marker loci distributed across 20 linkage groups. Five of the linkage groups exceed 100 cM in length, with the largest being 231 cM long. Assessment of colinearity between the Brachypodium linkage map and the rice genome sequence revealed significant regions of macrosynteny between the two genomes, as well as rearrangements similar to those reported in other grass comparative structural genomics studies. The Brachypodium genetic linkage map described here will serve as a new tool to pursue a range of molecular genetic analyses and other applications in this new model plant system.


Asunto(s)
Mapeo Cromosómico/métodos , Repeticiones de Microsatélite/genética , Modelos Teóricos , Poaceae/genética , Secuencia de Bases , Cromosomas de las Plantas , Análisis por Conglomerados , Genes de Plantas , Modelos Biológicos , Alineación de Secuencia , Análisis de Secuencia de ADN
6.
Mol Plant Microbe Interact ; 22(6): 665-76, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19445591

RESUMEN

Ptr ToxA (ToxA) is a proteinaceous necrotizing host-selective toxin produced by Pyrenophora tritici-repentis, a fungal pathogen of wheat (Triticum aestivum). In this study, we have found that treatment of ToxA-sensitive wheat leaves with ToxA leads to a light-dependent accumulation of reactive oxygen species (ROS) that correlates with the onset of necrosis. Furthermore, the accumulation of ROS and necrosis could be inhibited by the antioxidant N-acetyl cysteine, providing further evidence that ROS production is required for necrosis. Microscopic evaluation of ToxA-treated whole-leaf tissue indicated that ROS accumulation occurs in the chloroplasts. Analysis of total protein extracts from ToxA-treated leaves showed a light-dependent reduction of the chloroplast protein RuBisCo. In addition, Blue native-gel electrophoresis followed by sodium dodecyl sulfate polyacrylamide gel electrophoresis analysis revealed that ToxA induces changes in photosystem I (PSI) and photosystem II (PSII) in the absence of light, and therefore, the absence of ROS. When ToxA-treated leaves were exposed to light, all proteins in both PSI and PSII were extremely reduced. We propose that ToxA induces alterations in PSI and PSII affecting photosynthetic electron transport, which subsequently leads to ROS accumulation and cell death when plants are exposed to light.


Asunto(s)
Ascomicetos/patogenicidad , Micotoxinas/farmacología , Especies Reactivas de Oxígeno/metabolismo , Triticum/microbiología , Acetilcisteína/farmacología , Ascomicetos/metabolismo , Muerte Celular/efectos de los fármacos , Cloroplastos/efectos de los fármacos , Cloroplastos/metabolismo , Cloroplastos/ultraestructura , Depuradores de Radicales Libres/farmacología , Complejo de Proteína del Fotosistema I/metabolismo , Complejo de Proteína del Fotosistema II/metabolismo , Hojas de la Planta/metabolismo , Hojas de la Planta/ultraestructura , Proteínas de Plantas/metabolismo , Triticum/efectos de los fármacos
7.
Stem Cells Transl Med ; 7(4): 333-341, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29405603

RESUMEN

The aim of this exploratory study was to assess the safety and clinical effects of autologous umbilical cord blood (AUCB) infusion in children with idiopathic autism spectrum disorder (ASD). Twenty-nine children 2 to 6 years of age with a confirmed diagnosis of ASD participated in this randomized, blinded, placebo-controlled, crossover trial. Participants were randomized to receive AUCB or placebo, evaluated at baseline, 12, and 24 weeks, received the opposite infusion, then re-evaluated at the same time points. Evaluations included assessments of safety, Expressive One Word Picture Vocabulary Test, 4th edition, Receptive One Word Picture Vocabulary Test, 4th edition, Clinical Global Impression, Stanford-Binet Fluid Reasoning and Knowledge, and the Vineland Adaptive Behavior and Socialization Subscales. Generalized linear models were used to assess the effects of the response variables at the 12- and 24-week time periods under each condition (AUCB, placebo). There were no serious adverse events. There were trends toward improvement, particularly in socialization, but there were no statistically significant differences for any endpoints. The results of this study suggest that autologous umbilical cord infusions are safe for children with ASD. Tightly controlled trials are necessary to further progress the study of AUCB for autism. Stem Cells Translational Medicine 2018;7:333-341.


Asunto(s)
Trastorno del Espectro Autista/terapia , Transfusión de Sangre Autóloga/efectos adversos , Sangre Fetal/citología , Células Madre/citología , Cordón Umbilical/citología , Niño , Preescolar , Estudios Cruzados , Método Doble Ciego , Humanos
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