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7.
Ann Oncol ; 30(5): 774-780, 2019 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-30860570

RESUMEN

BACKGROUND: BEECH investigated the efficacy of capivasertib (AZD5363), an oral inhibitor of AKT isoforms 1-3, in combination with the first-line weekly paclitaxel for advanced or metastatic estrogen receptor-positive (ER+)/human epidermal growth factor receptor 2-negative (HER2-) breast cancer, and in a phosphoinositide 3-kinase, catalytic, alpha polypeptide mutation sub-population (PIK3CA+). PATIENTS AND METHODS: BEECH consisted of an open-label, phase Ib safety run-in (part A) in 38 patients with advanced breast cancer, and a randomised, placebo-controlled, double-blind, phase II expansion (part B) in 110 women with ER+/HER2- metastatic breast cancer. In part A, patients received paclitaxel 90 mg/m2 (days 1, 8 and 15 of a 28-day cycle) with capivasertib taken twice daily (b.i.d.) at two intermittent ascending dosing schedules. In part B, patients were randomly assigned, stratified by PIK3CA mutation status, to receive paclitaxel with either capivasertib or placebo. The primary end point for part A was safety to recommend a dose and schedule for part B; primary end points for part B were progression-free survival (PFS) in the overall and PIK3CA+ sub-population. RESULTS: Capivasertib was well tolerated, with a 400 mg b.i.d. 4 days on/3 days off treatment schedule selected in part A. In part B, median PFS in the overall population was 10.9 months with capivasertib versus 8.4 months with placebo [hazard ratio (HR) 0.80; P = 0.308]. In the PIK3CA+ sub-population, median PFS was 10.9 months with capivasertib versus 10.8 months with placebo (HR 1.11; P = 0.760). Based on the Common Terminology Criteria for Adverse Event v4.0, the most common grade ≥3 adverse events in the capivasertib group were diarrhoea, hyperglycaemia, neutropoenia and maculopapular rash. Dose intensity of paclitaxel was similar in both groups. CONCLUSIONS: Capivasertib had no apparent impact on the tolerability and dose intensity of paclitaxel. Adding capivasertib to weekly paclitaxel did not prolong PFS in the overall population or PIK3CA+ sub-population of ER+/HER2- advanced/metastatic breast cancer patients.ClinicalTrials.gov: NCT01625286.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/genética , Fosfatidilinositol 3-Quinasa Clase I/genética , Proteínas Proto-Oncogénicas c-akt/antagonistas & inhibidores , Receptores de Estrógenos/metabolismo , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Biomarcadores de Tumor/genética , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Fosfatidilinositol 3-Quinasa Clase I/metabolismo , Método Doble Ciego , Femenino , Humanos , Mutación , Metástasis de la Neoplasia , Recurrencia Local de Neoplasia/tratamiento farmacológico , Recurrencia Local de Neoplasia/genética , Recurrencia Local de Neoplasia/metabolismo , Recurrencia Local de Neoplasia/patología , Paclitaxel/administración & dosificación , Paclitaxel/efectos adversos , Pirimidinas/administración & dosificación , Pirimidinas/efectos adversos , Pirroles/administración & dosificación , Pirroles/efectos adversos , Tasa de Supervivencia
9.
Rev. chil. radiol ; 24(1): 5-11, mar. 2018. tab
Artículo en Español | LILACS | ID: biblio-959567

RESUMEN

Resumen:Existen diversos documentos y recomendaciones internacionales sobre nombres, conceptos, definiciones y campos de aplicación para diversas magnitudes y unidades utilizadas para monitorear los niveles de radiación ionizante a los que son expuestos los trabajadores durante los procedimientos de Radiodiagnóstico e Intervencionismo. Sin embargo, la legislación nacional, al igual que para la dosimetría de los pacientes, no se encuentra actualizada en este sentido y no contempla en sus documentos un glosario actualizado que permita encontrar en forma rápida y precisa este tipo de información. Por lo anterior, este trabajo de revisión corresponde a un segundo documento guía, complementario a nuestro trabajo publicado en 2015 titulado "Magnitudes y unidades para dosimetría a pacientes en radiodiagnóstico e intervencionismo", que describe de manera didáctica y en un lenguaje sencillo para los profesionales de la salud y áreas afines, las principales magnitudes y unidades que se deben conocer y utilizar en la dosimetría ocupacional de los trabajadores que participan en procedimientos de Radiodiagnóstico e Intervencionismo.


Abstract: There are many documents and international recommendations offer names, concepts, definitions and fields of application for various quantities and units used to monitor the exposure levels of ionising radiation to which workers are exposed during the diagnostic and interventional radiology procedures. However, as in the case of patient dosimetry, national legislation is not up-to-date in this area and nowhere does it establish an up-to-date glossary that would facilitate rapid and precise location of this kind of information. In light of the foregoing, this review paper presents a second guidance document, complementary to our published article in 2015 titled "Quantities and units used in patient dosimetry in radiodiagnostic and intervencional procedures", which describes the principal quantities and units that must be known and used in occupational dosimetry for workers participating in diagnostic and interventional radiology procedures, in a didactical manner and using simple language for professionals in health and similar areas.


Asunto(s)
Humanos , Protección Radiológica/normas , Personal de Salud , Dosimetría/métodos , Exposición a la Radiación/prevención & control , Exposición Profesional
10.
J Mater Chem B ; 5(26): 5284, 2017 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-32264115

RESUMEN

Correction for 'Functionalised type-I collagen as a hydrogel building block for bio-orthogonal tissue engineering applications' by R. Ravichandran et al., J. Mater. Chem. B, 2016, 4, 318-326.

11.
J Mater Chem B ; 5(45): 8925-8928, 2017 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-32264118

RESUMEN

Three new collagen mimetic peptides containing the CLK motif as anchoring arms were tested for silver nanoparticle surface stabilization. Our experimental and molecular dynamics data indicate that peptide length has an important effect not only in the resulting nanosilver's colloidal stability, but also in the biological performance of the composite.

12.
Org Biomol Chem ; 14(17): 4023-6, 2016 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-27065020

RESUMEN

A novel synthesized nitroxide amide-BODIPY prefluorescent probe was used to study cellular redox balance that modulates nitroxide/hydroxylamine ratio in cultured human fibroblasts. FLIM quantitatively differentiated between nitroxide states of the cytoplasm-localized probe imaged by TIRF, monitoring nitroxide depletion by hydrogen peroxide; eluding incorrect interpretation if only fluorescence intensity is considered.


Asunto(s)
Amidas/química , Compuestos de Boro/química , Fibroblastos/metabolismo , Colorantes Fluorescentes/química , Óxidos de Nitrógeno/química , Células Cultivadas , Colorantes Fluorescentes/síntesis química , Humanos , Peróxido de Hidrógeno/química , Microscopía Fluorescente , Oxidación-Reducción
13.
J Intern Med ; 280(3): 276-86, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27098482

RESUMEN

The cornea is the transparent front part of the eye that transmits light to the back of the eye to generate vision. Loss of corneal transparency, if irreversible, leads to severe vision loss or blindness. For decades, corneal transplantation using human donor corneas has been the only option for treating corneal blindness. Despite recent improvement in surgical techniques, donor cornea transplantation remains plagued by risks of suboptimal optical results and visual acuity, immune rejection and eventually graft failure. Furthermore, the demand for suitable donor corneas is increasing faster than the number of donors, leaving thousands of curable patients untreated worldwide. Here, we critically review the state of the art of biomaterials for corneal regeneration. However, the lessons learned from the use of the cornea as a disease model will allow for extension of the biomaterials and techniques for regeneration of more complex organs such as the heart.


Asunto(s)
Córnea/fisiología , Trasplante de Córnea , Regeneración , Ingeniería de Tejidos , Materiales Biomiméticos , Humanos , Prótesis e Implantes , Diseño de Prótesis
14.
Nanoscale ; 8(12): 6484-9, 2016 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-26949000

RESUMEN

Despite the broad anti-microbial and anti-inflammatory properties of silver nanoparticles (AgNPs), their use in bioengineered corneal replacements or bandage contact lenses has been hindered due to their intense yellow coloration. In this communication, we report the development of a new strategy to pre-stabilize and incorporate AgNPs with different colours into collagen matrices for fabrication of corneal implants and lenses, and assessed their in vitro and in vivo activity.


Asunto(s)
Antiinfecciosos/administración & dosificación , Córnea/cirugía , Trasplante de Córnea/instrumentación , Nanopartículas del Metal/química , Medicina Regenerativa/métodos , Plata/química , Animales , Péptidos Catiónicos Antimicrobianos/química , Materiales Biocompatibles , Colágeno/química , Trasplante de Córnea/métodos , Hidrogeles/química , Interleucina-6/metabolismo , Cristalino/cirugía , Ensayo de Materiales , Ratones , Nanomedicina/métodos , Estrés Mecánico , Resistencia a la Tracción , Catelicidinas
15.
Chem Phys Lipids ; 196: 13-23, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26855412

RESUMEN

Hydrogel films possess the ability of retain water and deliver it to a phospholipid bilayer mainly composed by DPPC (1,2-dipalmitoyl-sn-glycero-3-phosphocholine); moisture of the medium favors the stability of an artificial biomembrane when it is subjected to repetitive heating cycles. This hypothesis is valid when the hydrogel film, used as scaffold, present a flat surface morphology and a high ability for water releasing. On the other hand, when the sample presents a wrinkle topography (periodic undulations), free lateral molecular movement of the bilayer becomes lower, disfavoring the occurrence of clear phases/phase transitions according to applied temperature. Hydrogel films were prepared using HEMA (hydroxyethylmetacrylate), different crosslinking agents and initiators. This reaction mixture was spread over hydrophilic silicon wafers using spin coating technique. Resultant films were then exposed to UV light favoring polymeric chain crosslinking and interactions between hydrogel and substrate; this process is also known to generate tensile stress mismatch between different hydrogel strata, producing out-of-plane net force that generate ordered undulations or collapsed crystals at surface level. DPPC bilayers were then placed over hydrogel using Langmuir-Blodgett technique. Surface morphology was detected in order to clarify the behavior of these films. Obtained data corroborate DPPC membrane stability making possible to detect phases/phase transitions by ellipsometric methods and Atomic Force Microscopy due to their high hydration level. This system is intended to be used as biosensor through the insertion of transmembrane proteins or peptides that detect minimal variations of some analyte in the environment; artificial biomembrane stability and behavior is fundamental for this purpose.


Asunto(s)
Hidrogeles/química , Membranas Artificiales , Andamios del Tejido , Microscopía de Fuerza Atómica , Propiedades de Superficie
16.
J Mater Chem B ; 4(2): 318-326, 2016 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-32263374

RESUMEN

In this study, we derivatized type I collagen without altering its triple helical conformation to allow for facile hydrogel formation via the Michael addition of thiols to methacrylates without the addition of other crosslinking agents. This method provides the flexibility needed for the fabrication of injectable hydrogels or pre-fabricated implantable scaffolds, using the same components by tuning the modulus from Pa to kPa. Enzymatic degradability of the hydrogels can also be easily fine-tuned by variation of the ratio and the type of the cross-linking component. The structural morphology reveals a lamellar structure mimicking native collagen fibrils. The versatility of this material is demonstrated by its use as a pre-fabricated substrate for culturing human corneal epithelial cells and as an injectable hydrogel for 3-D encapsulation of cardiac progenitor cells.

17.
Rev. chil. cir ; 67(5): 535-537, oct. 2015. ilus
Artículo en Español | LILACS | ID: lil-762629

RESUMEN

Background: Anatomical abnormalities of the liver are rare and their association with gallbladder agenesis are even more uncommon. Case report: We report a 63 years old man complaining of jaundice, without pain or fever. A magnetic resonance imaging showed a right hepatic lobe agenesis associated with gallbladder agenesis. Jaundice subsided spontaneously.


Introducción: Las anomalías anatómicas del hígado son raras, la asociación a una agenesia vesicular es más infrecuente aún, siendo su diagnóstico generalmente un hallazgo. Caso clínico: Presentamos el caso de un paciente masculino de 63 años que consulta por ictericia, sin dolor ni fiebre, al cual se le realiza diagnóstico por imagen con resonancia magnética de agenesia de lóbulo hepático derecho asociado a agenesia vesicular. Dado que el paciente no tiene litiasis biliar, se decide tratamiento médico.


Asunto(s)
Humanos , Masculino , Persona de Mediana Edad , Hígado/anomalías , Hígado/cirugía , Hígado/patología , Vesícula Biliar/anomalías , Vesícula Biliar/cirugía , Vesícula Biliar/patología , Hígado , Ictericia , Tomografía Computarizada por Rayos X
18.
Rev. chil. radiol ; 21(3): 94-99, 2015. ilus, tab
Artículo en Español | LILACS | ID: lil-771668

RESUMEN

Because diagnostic and interventional radiology procedures represent one of the main sources of irradiation by ionizing radiation in the population, it has become a priority to become familiar with the quantities and units that account for patient dosimetry. There are countless documents and international recommendations on names, concepts, definitions and areas of application for various quantities and units used in patient dosimetry, in interventional and diagnostic radiology procedures. However, national legislation is not updated in this regard and does not provide, in any of its documents, an updated glossary that enables finding this type of information quickly and precisely. Therefore, this review paper presents in a didactic way and in plain language, the main quantities and units to be used in the dosimetry of patients undergoing diagnostic and interventional radiology procedures.


Debido a que los procedimientos de radiodiagnóstico e intervencionismo representan una de las principales fuentes de irradiación a la población por radiaciones ionizantes, se vuelve prioritario conocer las magnitudes y unidades que dan cuenta de la dosimetría a los pacientes. Existen innumerables documentos y recomendaciones internacionales sobre nombres, conceptos, definiciones y campos de aplicación para diversas magnitudes y unidades utilizadas en la dosimetría de pacientes en procedimientos de radiodiagnóstico e intervencionismo. Sin embargo, la legislación nacional no se encuentra actualizada en este sentido y no contempla en ninguno de sus documentos, un glosario actualizado que permita encontrar en forma rápida y precisa este tipo de información. Por lo anterior, este trabajo de revisión presenta de manera didáctica y en un lenguaje sencillo, las principales magnitudes y unidades que se deben utilizar en la dosimetría de pacientes sometidos a procedimientos de radiodiagnóstico e intervencionismo.


Asunto(s)
Humanos , Diagnóstico por Imagen/normas , Kerma , Radiografía Intervencional/normas , Radiometría/normas
20.
Phys Rev Lett ; 111(19): 195701, 2013 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-24266478

RESUMEN

Transition metals Ti, Zr, and Hf have a hexagonal close-packed structure (α) at ambient conditions, but undergo phase transformations with increasing temperature and pressure. Of particular significance is the high-pressure hexagonal ω phase which is brittle compared to the α phase. There has been a long debate about transformation mechanisms and orientation relations between the two crystal structures. Here we present the first high pressure experiments with in situ synchrotron x-ray diffraction texture studies on polycrystalline aggregates. We follow crystal orientation changes in Zr, confirming the original suggestion by Silcock for an α→ω martensitic transition for Ti, with (0001)(α)||(1120)(ω), and a remarkable orientation memory when ω reverts back to α.

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