Search results for "procedures"
showing 10 items of 1678 documents
External stenting with a new polyester mesh reduces neointimal hyperplasia of vein grafts in a sheep model.
2007
Objective External stents placed around vein grafts have demonstrated effectiveness in reducing neointimal hyperplasia by preventing distension of the thin-walled vein grafts when exposed to arterial pressure. However, the ideal stent material has yet to be defined. The following study investigates the short- and long-term effects of an innovative polyester mesh stent designed with optimized adaptation of circumferential compliance. Methods Following in vitro definition of the ideal macro-porous polyester stent material, a total of 12 sheep underwent implantation of bilateral carotid artery vein graft bypasses. In six sheep, the short-term outcome (four weeks of implantation) was investigat…
Implantation of a polycaprolactone scaffold with subchondral bone anchoring ameliorates nodules formation and other tissue alterations
2015
Purpose: Articular cartilage has limited repair capacity. Two different implant devices for articular cartilage regeneration were tested in vivo in a sheep model to evaluate the effect of subchondral bone anchoring for tissue repair. Methods: The implants were placed with press-fit technique in a cartilage defect after microfracture surgery in the femoral condyle of the knee joint of the sheep and histologic and mechanical evaluation was done 4.5 months later. The first group consisted of a biodegradable polycaprolactone (PCL) scaffold with double porosity. The second test group consisted of a PCL scaffold attached to a poly(L-lactic acid) (PLLA) pin anchored to the subchondral bone. Result…
Under Pressure: Comparison of Aspiration Techniques for Endovascular Mechanical Thrombectomy.
2018
BACKGROUND AND PURPOSE: Blood flow should be interrupted during mechanical thrombectomy to prevent embolization of clot fragments. The purpose of our study was to provide a handy overview of the most common aspiration devices and to quantify their flow characteristics. MATERIALS AND METHODS: We assessed volumetric flow rates generated by a 60-mL VacLok vacuum pressure syringe, a Pump MAX aspiration pump, and a Dominant Flex suction pump connected to the following: 1) an 8F long sheath, 2) an 8F balloon-guide catheter, 3) an ACE 64 distal aspiration catheter, and 4) an AXS Catalyst 6 Distal Access Catheter. We used a water/glycerol solution, which was kept at a constant temperature of 20°C (…
Polyphosphate, the physiological metabolic fuel for corneal cells: a potential biomaterial for ocular surface repair
2019
The regeneration of the epithelium, covering the avascular cornea, involves the processes of differentiation, proliferation and migration of cells originating from the corneal epithelial stem cells. We ask the question if these energy-consuming processes can be fueled by the physiological, inorganic polyphosphate (polyP), the main energy storage/donor molecule in the extracellular space. The ex vivo results reveal that addition of polyP, in the form of soluble Na-polyP, to the culture medium elicits a strong stimulatory effect on cell viability/growth and migration of corneal epithelial cells. Microscopic analyses of partially denuded cornea specimens show that in the presence of polyP, but…
Hospital and outpatient models for Hematopoietic Stem Cell Transplantation: A systematic review of comparative studies for health outcomes, experienc…
2021
The number of Hematopoietic Stem Cell Transplantations has risen in the past 20 years. The practice of outpatient Hematopoietic Stem Cell Transplantation programs is increasing in an attempt to improve the quality of patient care and reduce the demand for hospital admission. A systematic review of 29 comparative studies between in-hospital and outpatient treatment of Hematopoietic Stem Cell Transplantation, with no restriction by outpatient regime was conducted. This study aims to analyse the current evidence on the effects of the outpatient model on patient-centred outcomes, comparing both in-hospital and outpatient models for autologous and allogeneic HSCT using the Triple Aim framework: …
Improved technique for stereotactic placement of nerve grafts between two locations inside the rat brain
2008
Peripheral nerve grafts have shown the ability to facilitate central axonal growth and regenerate the adult central nervous system. However, the detailed description of a technique for atraumatic graft placement within the brain is lacking. We present a stereotactic procedure to implant a peripheral nerve graft within a rat's brain with minimal brain tissue damage. The procedure permits a correct graft placement joining two chosen points, and the survival and integration of the graft in the host tissue with a light glial reaction, with evidence of central axonal growth inside the graft, at least up to 8 weeks after its implantation. (C) 2008 Elsevier B.V. All rights reserved.
Effect of bioglass on growth and biomineralization of SaOS-2 cells in hydrogel after 3D cell bioprinting.
2014
We investigated the effect of bioglass (bioactive glass) on growth and mineralization of bone-related SaOS-2 cells, encapsulated into a printable and biodegradable alginate/gelatine hydrogel. The hydrogel was supplemented either with polyphosphate (polyP), administered as polyP • Ca2+-complex, or silica, or as biosilica that had been enzymatically prepared from ortho-silicate by silicatein. These hydrogels, together with SaOS-2 cells, were bioprinted to computer-designed scaffolds. The results revealed that bioglass (nano)particles, with a size of 55 nm and a molar ratio of SiO2 : CaO : P2O5 of 55 : 40 : 5, did not affect the growth of the encapsulated cells. If silica, biosilica, or polyP …
Beyond sentinel node algorithm. Toward a more tailored surgery for cervical cancer patients
2016
none 12 Nowadays cervical cancer is frequently diagnosed at early stage. For these patients lymph node metastasis (LNM) is considered the most important prognostic factor. During the last decade many efforts have been made to reduce rate of complications associated with lymphadenectomy (LND). A great interest has arisen in sentinel lymph node (SLN) biopsy as a technique able to decrease number of LND performed and, at the same time, to assess lymph nodal status. High diagnostic performances have been reached thanks to SLN surgical algorithm. However, despite the efforts, about 25% of these patients undergo at least unilateral LND to meet NCCN recommendations. Data of women with Internationa…
An Overview of Green Analytical Techniques in the Spectrometric Analysis of Environmental and Biological Samples
2009
ABSTRACT This literature survey presents in a nutshell different parameters for the effectiveness of the green spectrometric procedures, which have been applied to the determination of organics, inorganics, and metal ions in different matrices. The following issues were considered: the main aspects of miniaturization, reagent replacement, reduction of wastes, and on-line recovery and detoxification, which made the analytical procedures sustainable. Also, a discussion of analytical characteristics along with spectrometric methodologies and applications is included.
Implementation of gradients of organic solvent in micellar liquid chromatography using DryLab®: Separation of basic compounds in urine samples
2014
In micellar liquid chromatography (MLC), chromatographic peaks are more evenly distributed compared to conventional reversed-phase liquid chromatography (RPLC). This is the reason that most procedures are implemented using isocratic elution. However, gradient elution may be still useful in MLC to analyse mixtures of compounds within a wide range of polarities, decreasing the analysis time. Also, it benefits the determination of moderately to low polar compounds in physiological fluids performing direct injection: an initial micellar eluent with a low organic solvent content, or a pure micellar (without surfactant) solution, will provide better protection of the column against the proteins i…