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1.
Macromol Rapid Commun ; 40(1): e1800608, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30417498

RESUMEN

The world population will rapidly grow from 7 to 9 billion by 2050 and this will parallel a surging annual plastics consumption from today's 350 million tons to well beyond 1 billion tons. The switch from a linear economy with its throwaway culture to a circular economy with efficient reuse of waste plastics is therefore mandatory. Hydrocarbon polymers, accounting for more than half the world's plastics production, enable closed-loop recycling and effective product-stewardship systems. High-molar-mass hydrocarbons serve as highly versatile, cost-, resource-, eco- and energy-efficient, durable lightweight materials produced by solvent-free, environmentally benign catalytic olefin polymerization. Nanophase separation and alignment of unentangled hydrocarbon polymers afford 100% recyclable self-reinforcing all-hydrocarbon composites without requiring the addition of either alien fibers or hazardous nanoparticles. Recycling of durable hydrocarbons is far superior to biodegradation. The facile thermal degradation enables liquefaction and quantitative recovery of low molar mass hydrocarbon oil and gas. Teamed up with biomass-to-liquid and carbon dioxide-to-fuel conversions, powered by renewable energy, waste hydrocarbons serve as renewable hydrocarbon feedstocks for the synthesis of high molar mass hydrocarbon materials. Herein, an overview is given on how innovations in catalyst and process technology enable tailoring of advanced recyclable hydrocarbon materials meeting the needs of sustainable development and a circular economy.


Asunto(s)
Hidrocarburos/economía , Polímeros/economía , Hidrocarburos/química , Polímeros/química
2.
Int J Mol Sci ; 19(10)2018 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-30301253

RESUMEN

A new form-stable composite phase change material (PEG/ASB) composed of almond shell biochar (ASB) and polyethylene glycol (PEG) was produced via a simple and easy vacuum impregnation method. The supporting material ASB, which was cost effective, environmentally friendly, renewable and rich in appropriate pore structures, was produced from agricultural residues of almond shells by a simple pyrolysis method, and it was firstly used as the matrix of PEG. Different analysis techniques were applied to investigate the characteristics of PEG/ASB, including structural and thermal properties, and the interaction mechanism between ASB and PEG was studied. The thermogravimetric analysis (TGA) and thermal cycle tests demonstrated that PEG/ASB possessed favorable thermal stability. The differential scanning calorimetry (DSC) curves demonstrated that the capacities for latent heat storage of PEG/ASB were enhanced with increasing PEG weight percentage. Additionally, PEG/ASB had an excellent thermal conductivity of 0.402 W/mK, which was approximately 1.6 times higher than that of the pure PEG due to the addition of ASB. All the study results indicated that PEG/ASB had favorable phase change properties, which could be used for thermal energy storage.


Asunto(s)
Carbón Orgánico/química , Transición de Fase , Polímeros/síntesis química , Prunus dulcis/química , Costos y Análisis de Costo , Polietilenglicoles/química , Polímeros/economía , Eliminación de Residuos/economía , Eliminación de Residuos/métodos , Conductividad Térmica
3.
BMC Biotechnol ; 17(1): 20, 2017 02 23.
Artículo en Inglés | MEDLINE | ID: mdl-28231788

RESUMEN

BACKGROUND: poly(L-malic acid) (PMA) is a water-soluble polyester with many attractive properties in medicine and food industries, but the high cost of PMA fermentation has restricted its further application for large-scale production. To overcome this problem, PMA production from Jerusalem artichoke tubers was successfully performed. Additionally, a valuable exopolysaccharide, pullulan, was co-produced with PMA by Aureobasidum pullulans HA-4D. RESULTS: The Jerusalem artichoke medium for PMA and pullulan co-production contained only 100 g/L hydrolysate sugar, 30 g/L CaCO3 and 1 g/L NaNO3. Compared with the glucose medium, the Jerusalem artichoke medium resulted in a higher PMA concentration (114.4 g/L) and a lower pullulan concentration (14.3 g/L) in a 5 L bioreactor. Meanwhile, the activity of pyruvate carboxylase and malate dehydrogenas was significantly increased, while the activity of α-phosphoglucose mutase, UDP-glucose pyrophosphorylase and glucosyltransferase was not affected. To assay the economic-feasibility, large-scale production in a 1 t fermentor was performed, yielding 117.5 g/L PMA and 15.2 g/L pullulan. CONCLUSIONS: In this study, an economical co-production system for PMA and pullulan from Jerusalem artichoke was developed. The medium for PMA and pullulan co-production was significantly simplified when Jerusalem artichoke tubers were used. With the simplified medium, PMA production was obviously stimulated, which would be associated with the improved activity of pyruvate carboxylase and malate dehydrogenas.


Asunto(s)
Ascomicetos/metabolismo , Glucanos/economía , Glucanos/metabolismo , Helianthus/metabolismo , Malatos/economía , Malatos/metabolismo , Polímeros/economía , Polímeros/metabolismo , Ascomicetos/genética , Técnicas de Cultivo Celular por Lotes/métodos , Ingeniería Genética/economía , Ingeniería Genética/métodos , Glucanos/genética , Glucanos/aislamiento & purificación , Helianthus/genética , Malatos/aislamiento & purificación , Tubérculos de la Planta/genética , Tubérculos de la Planta/metabolismo , Polímeros/aislamiento & purificación
4.
Macromol Rapid Commun ; 38(14)2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28488384

RESUMEN

Photoluminescence (PL) of nonconjugated polymers brings a favorable opportunity for low-cost and nontoxic luminescent materials, while most of them still exhibit relatively weak emission. Strong PL from poly[(maleic anhydride)-alt-(vinyl acetate)] (PMV) from low-cost monomer has been found in organic solvents, yet the necessity of noxious solvents would hinder its practical applications. Herein, through a novel, eco-friendly, and one-step route, PMV-derived PL polymers can be fabricated with the highest quantum yield of 87% among water-soluble nonconjugated PL polymers ever reported. These PMV-derived polymers emit strong blue emission in both solutions and solids, and can be transformed into red-emission agents easily. These PL polymers exhibit application potentials in light-conversion agricultural films. It is assumed that this work not only puts forward a convenient preparation routine for nonconjugated polymers with high PL, but also provides an industrial application possibility for them.


Asunto(s)
Fotoquímica , Polímeros/química , Luminiscencia , Sustancias Macromoleculares , Polimerizacion , Polímeros/economía , Solventes , Agua
5.
J Sep Sci ; 39(10): 1963-70, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-27027975

RESUMEN

The combination of molecular crowding and virtual imprinting was employed to develop a cost-effective method to prepare molecularly imprinted polymers. By using linear polymer polystyrene as a macromolecular crowding agent, an imprinted polymer recognizable to punicalagin had been successfully synthesized with punicalin as the dummy template. The resulting punicalin-imprinted polymer presented a remarkable selectivity to punicalagin with an imprinting factor of 3.17 even at extremely low consumption of the template (template/monomer ratio of 1:782). In contrast, the imprinted polymer synthesized without crowding agent, did not show any imprinting effect at so low template amount. The imprinted polymers made by combination of molecular crowding and virtual imprinting can be utilized for the fast separation of punicalagin from pomegranate husk extract after optimizing the protocol of solid-phase extraction with the recovery of 85.3 ± 1.2%.


Asunto(s)
Taninos Hidrolizables/aislamiento & purificación , Lythraceae/química , Impresión Molecular/economía , Extractos Vegetales/aislamiento & purificación , Taninos Hidrolizables/química , Taninos Hidrolizables/economía , Sustancias Macromoleculares/química , Sustancias Macromoleculares/economía , Extractos Vegetales/química , Extractos Vegetales/economía , Polímeros/química , Polímeros/economía , Extracción en Fase Sólida/economía
6.
Chemphyschem ; 16(17): 3687-94, 2015 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-26377950

RESUMEN

To impart biocompatibility, stability, and specificity to quantum dots (QDs)-and to reduce their toxicity-it is essential to carry out surface modification. However, most surface-modification processes are costly, complicated, and time-consuming. In addition, the modified QDs often have a large size, which leads to easy aggregation in biological environments, making it difficult to excrete them from in vivo systems. To solve these problems, three kinds of conventional polymers, namely, polyvinyl alcohol (PVA, neutral), sodium polystyrene sulfonate (PSS, negative charged), and poly(diallyl dimethyl ammonium chloride) (PDDA, positive charged) were selected to modify the surface of QDs at low cost via a simple process in which the size of the QDs was kept small after modification. The effect of polymer modification on the photoluminescence (PL) properties of the QDs was systematically investigated. High quantum yields (QYs) of 65 % were reached, which is important for the realization of bio-imaging. Then, the cytotoxicity of CdTe QD-polymer composites was systematically investigated via MTT assay using the Cal27 and HeLa cell lines, especially for high concentrations of QD-polymer composites in vitro. The experimental results showed that the cytotoxicity decreased in the order CdTe-PDDA>CdTe>CdTe-PSS>CdTe-PVA, indicating that PSS and PVA can reduce the toxicity of the QDs. An obvious cytotoxicity of CdTe-PVA and CdTe-PSS was present until 120 h for the Cal27 cell line and until 168 h for the HeLa cell line. At last, the Cal27 cell line was selected to realize bio-imaging using CdTe-PSS and CdTe-PVA composites with different emission colors under one excitation wavelength.


Asunto(s)
Compuestos de Cadmio/química , Luminiscencia , Imagen Molecular , Polímeros/química , Polímeros/economía , Puntos Cuánticos/química , Telurio/química , Compuestos de Cadmio/efectos adversos , Compuestos de Cadmio/economía , Línea Celular Tumoral , Células HeLa , Humanos , Estructura Molecular , Tamaño de la Partícula , Procesos Fotoquímicos , Puntos Cuánticos/efectos adversos , Puntos Cuánticos/economía , Propiedades de Superficie , Telurio/efectos adversos , Telurio/economía
7.
J Am Acad Dermatol ; 73(6): 1040-54.e14, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26481056

RESUMEN

HIV facial lipoatrophy (FLA) is characterized by facial volume loss. HIV FLA affects the facial contours of the cheeks, temples, and orbits, and is associated with social stigma. Although new highly active antiretroviral therapy medications are associated with less severe FLA, the prevalence of HIV FLA among treated individuals exceeds 50%. The goal of our systematic review is to examine published clinical studies involving the use of filler agents for aesthetic treatment of HIV FLA and to provide evidence-based recommendations based on published efficacy and safety data. A systematic review of the published literature was performed on July 1, 2015, on filler agents for aesthetic treatment of HIV FLA. Based on published studies, poly-L-lactic acid is the only filler agent with grade of recommendation: B. Other reviewed filler agents received grade of recommendation: C or D. Poly-L-lactic acid may be best for treatment over temples and cheeks, whereas calcium hydroxylapatite, with a Food and Drug Administration indication of subdermal implantation, may be best used deeply over bone for focal enhancement. Additional long-term randomized controlled trials are necessary to elucidate the advantages and disadvantages of fillers that have different biophysical properties, in conjunction with cost-effectiveness analysis, for treatment of HIV FLA.


Asunto(s)
Rellenos Dérmicos/administración & dosificación , Cara , Síndrome de Lipodistrofia Asociada a VIH/terapia , Ácido Láctico/administración & dosificación , Polímeros/administración & dosificación , Técnicas Cosméticas , Análisis Costo-Beneficio , Rellenos Dérmicos/economía , Estética , Femenino , Síndrome de Lipodistrofia Asociada a VIH/diagnóstico , Humanos , Ácido Láctico/economía , Masculino , Poliésteres , Polímeros/economía , Medición de Riesgo , Índice de Severidad de la Enfermedad , Resultado del Tratamiento
8.
Biomacromolecules ; 15(6): 2067-78, 2014 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-24762265

RESUMEN

Clinical and industrial applications of human pluripotent stem cells (hPSC) require large amounts of cells that have been expanded under defined conditions. Labor-intensive techniques and ill-defined or expensive compounds and substrates are not applicable. Here we describe a chemically defined synthetic substrate consisting of polysulfone (PSF) membranes coated with polymerized 3,4-dihydroxy-l-phenylalanine (DOPA). DOPA/PSF is inexpensive and can be easily produced at various shapes and sizes. DOPA/PSF supports long-term self-renewal of undifferentiated human embryonic (hESC) and human induced pluripotent stem cells (hiPSC) under defined conditions. Pluripotency is maintained for at least 10 passages. Adhesion of hPSC to DOPA/PSF is mainly mediated by a specific integrin heterodimer. Proliferation and gene expression patterns on DOPA/PSF and control substrates are comparable. Labor-intensive cultivation methods and use of serum or coating with proteins are not required. Together, these features make DOPA/PSF attractive for applications where large-scale expansion of human pluripotent stem cells under defined conditions is essential.


Asunto(s)
Técnicas de Cultivo de Célula/métodos , Análisis Costo-Beneficio , Dihidroxifenilalanina/química , Células Madre Pluripotentes Inducidas/efectos de los fármacos , Polímeros/química , Sulfonas/química , Técnicas de Cultivo de Célula/economía , Proliferación Celular/efectos de los fármacos , Proliferación Celular/fisiología , Análisis Costo-Beneficio/métodos , Dihidroxifenilalanina/economía , Dihidroxifenilalanina/farmacología , Humanos , Células Madre Pluripotentes Inducidas/metabolismo , Polímeros/economía , Polímeros/farmacología , Especificidad por Sustrato/efectos de los fármacos , Especificidad por Sustrato/fisiología , Sulfonas/economía
9.
Pharmacoeconomics ; 38(7): 747-764, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32239480

RESUMEN

OBJECTIVES: Patients with chronic kidney disease (CKD) are commonly treated with renin-angiotensin-aldosterone system inhibitors (RAASi) in order to delay progression of renal disease. However, research has shown that RAASi in CKD patients increases hyperkalaemia (HK) prevalence, which leads to RAASi discontinuation or dose reduction with the loss of benefits on the kidney. Patiromer is a novel therapy for HK treatment and may enable patients to remain on their RAASi regimen. This study aimed to assess the cost-effectiveness of patiromer from a Swedish healthcare perspective. METHODS: A Markov model was developed to evaluate the economic outcomes of patiromer versus no patiromer in HK patients with stage 3-4 CKD taking RAASi. The model consisted of six health states reflecting disease progression and hospitalisations. The analysis mainly considered clinical data from the OPAL-HK trial and national costs. The main outcomes of interest were incremental costs (euro [EUR] 2016) and quality-adjusted life years (QALYs), discounted at 3%, and the incremental cost-effectiveness ratio (ICER). Extensive uncertainty analyses were performed. RESULTS: In comparison to no patiromer, a patiromer patient gained 0.14 QALYs and an incremental cost of EUR 6109 (Swedish krona [SEK] 57,850), yielding an ICER of EUR 43,307 (SEK 410,072)/QALY gained. The results were robust to a range of sensitivity analyses. At a willingness-to-pay threshold of EUR 52,804 (SEK 500,000)/QALY, patiromer had a 50% chance of being cost-effective. CONCLUSIONS: The results indicate that patiromer may demonstrate value for money in Swedish patients with stage 3-4 CKD, by enabling RAASi treatment. However, there is a considerable degree of uncertainty.


Asunto(s)
Hiperpotasemia/tratamiento farmacológico , Polímeros/administración & dosificación , Insuficiencia Renal Crónica/tratamiento farmacológico , Sistema Renina-Angiotensina/efectos de los fármacos , Anciano , Análisis Costo-Beneficio , Progresión de la Enfermedad , Quimioterapia Combinada , Femenino , Hospitalización/economía , Humanos , Masculino , Cadenas de Markov , Polímeros/economía , Años de Vida Ajustados por Calidad de Vida , Insuficiencia Renal Crónica/economía , Suecia , Incertidumbre
10.
Sci Rep ; 10(1): 2912, 2020 02 19.
Artículo en Inglés | MEDLINE | ID: mdl-32076086

RESUMEN

Disorders of the spine are among the most common indications for neurosurgical and orthopedic surgical interventions. Spinal fixation in the form of pedicle screw placement is a common form of instrumentation method in the lower cervical, thoracic, and lumbar spine. A vital principle to understand for the safe and accurate placement of pedicle screws is the palpable difference between the cortical and cancellous bone, both of which have different material properties and compositions. Probing and palpation of the hard cortical bone, also known as the "ventral lamina", covering the neural elements of the spinal canal during screw placement provides manual feedback to the surgeon, indicating an impending breach if continued directional force is applied. Generally, this practice is learned at the expense of patients in live operating room scenarios. Currently, there is a paucity of human vertebra simulation designs that have been validated based on the in vivo ultrastructure and physical properties of human cortical and cancellous bone. In this study, we examined the feasibility of combining three-dimensionally printed thermoplastic polymers with polymeric foam to replicate both the vertebral corticocancellous interface and surface anatomy for procedural education.


Asunto(s)
Hueso Esponjoso/fisiología , Hueso Cortical/fisiología , Plásticos/farmacología , Polímeros/farmacología , Impresión Tridimensional , Columna Vertebral/fisiología , Temperatura , Hueso Esponjoso/efectos de los fármacos , Hueso Cortical/efectos de los fármacos , Costos y Análisis de Costo , Estudios de Factibilidad , Calor , Humanos , Cinética , Modelos Anatómicos , Plásticos/economía , Polimerizacion , Polímeros/economía , Impresión Tridimensional/economía , Columna Vertebral/efectos de los fármacos
11.
Adv Biochem Eng Biotechnol ; 166: 427-468, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-28374047

RESUMEN

The number of newly developed bioplastics has increased sharply in recent years and innovative polymer materials are increasingly present on the plastics market. Bioplastics are not, however, a completely new kind of material, but rather a rediscovered class of materials within the familiar group of materials known as plastics. Therefore, existing knowledge from the plastics sector can and should be transferred to bioplastics in order to further increase their performance, material diversity and market penetration.


Asunto(s)
Plásticos , Industria Química/tendencias , Plásticos/química , Plásticos/economía , Polímeros/química , Polímeros/economía
12.
Lab Chip ; 19(22): 3776-3786, 2019 11 21.
Artículo en Inglés | MEDLINE | ID: mdl-31616896

RESUMEN

Multi-electrode arrays (MEAs) have become a key element in the study of cellular phenomena in vitro. Common modern MEAs are still based on costly microfabrication techniques, making them expensive tools that researchers are pushed to reuse, compromising the reproducibility and the quality of the acquired data. There is a need to develop novel fabrication strategies, able to produce disposable devices that incorporate advanced technologies beyond the standard metal electrodes on rigid substrates. Here we present an innovative fabrication process for the production of polymer-based flexible MEAs. The device fabrication exploited inkjet printing, as this low-cost manufacturing method allows for an easy and reliable patterning of conducting polymers. Poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) was used as the sole conductive element of the MEAs. The physical structure and the electrical properties of the plastic/printed MEAs (pMEAs) were characterised, showing a low impedance that is maintained also in the long term. The biocompatibility of the devices was demonstrated, and their capability to successfully establish a tight coupling with cells was proved. Furthermore, the pMEAs were used to monitor the extracellular potentials from cardiac cell cultures and to record high quality electrophysiological signals from them. Our results validate the use of pMEAs as in vitro electrophysiology platforms, pushing for the adoption of innovative fabrication techniques and the use of new materials for the production of MEAs.


Asunto(s)
Tinta , Impresión Tridimensional/economía , Compuestos Bicíclicos Heterocíclicos con Puentes/química , Compuestos Bicíclicos Heterocíclicos con Puentes/economía , Conductividad Eléctrica , Electrodos/economía , Fenómenos Electrofisiológicos , Polímeros/química , Polímeros/economía , Poliestirenos/química , Poliestirenos/economía , Impresión Tridimensional/instrumentación
13.
Eur J Trauma Emerg Surg ; 45(4): 665-670, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-30815719

RESUMEN

PURPOSE: A key step during laparoscopic appendicectomy is securing the appendiceal stump. This has traditionally been achieved using vicryl endoloops, but increasing evidence suggests that the use of polymeric clips (Hem-o-lok) may be a safe and viable method. Current evidence for its clinical use in laparoscopic appendicectomy is unknown. We performed a systematic review of the literature examining the clinical outcomes of laparoscopic appendicectomy using polymeric clips compared to other methods of stump closure. METHODS: A systematic literature review based on PRISMA guidelines was performed using MEDLINE, PubMed, EMBASE and Cochrane library databases between 2000 and 2017. All studies analysing appendiceal stump closure during laparoscopic appendicectomy using polymeric clips compared to other methods of stump closure were included. The methodological quality of the included studies was assessed using the Cochrane Handbook for Systematic Reviews. The review was registered with the PROSPERO register of systematic reviews. RESULTS: Ten studies were included, involving 702 patients, 7 of which were prospective studies and 1 a randomised control trial. Polymeric clips were found to be the cheapest method (€20.47 average per patient) and also had the lowest rate of complications (2.7%) compared to other commonly used closure methods. Meanwhile, operative time and duration of in-patient stay were similar between groups. CONCLUSIONS: Current evidence suggests that polymeric clips are an effective and cost-efficient method for stump closure in laparoscopic appendicectomy for acute appendicitis. Further high-quality evidence is required before polymeric clips can be recommended as the gold standard for appendiceal stump closure.


Asunto(s)
Apendicectomía/instrumentación , Apendicitis/cirugía , Laparoscopía/instrumentación , Apendicectomía/economía , Apendicitis/economía , Ahorro de Costo , Humanos , Laparoscopía/economía , Tiempo de Internación/economía , Tiempo de Internación/estadística & datos numéricos , Tempo Operativo , Polímeros/economía , Polímeros/uso terapéutico , Instrumentos Quirúrgicos/economía , Técnicas de Cierre de Heridas/economía , Técnicas de Cierre de Heridas/instrumentación
14.
Cardiovasc Revasc Med ; 20(9): 752-757, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-30638888

RESUMEN

OBJECTIVES: The study estimated the health economic impact of a latest generation coronary stent with ultrathin struts and bioresorbable polymer coating. BACKGROUND: The recent BIOFLOW V trial, an international FDA approval trial (ClinicalTrials.gov: NCT02389946), has shown that an ultrathin, bioresorbable polymer sirolimus-eluting stent had a significantly lower rate of target lesion failure and target vessel-related myocardial infarction than a thin, durable polymer everolimus-eluting stent at 12 months, driven by a lower rate of peri-procedural myocardial infarction (ppMI). METHODS: We used a Markov model to project mortality and cost outcomes of that lower ppMI rate from a U.S. health system perspective over a 12-month horizon. Model parameters were derived from BIOFLOW V trial data, a systematic literature review and expert interviews. RESULTS: Use of the bioresorbable polymer sirolimus-eluting stent compared to durable polymer everolimus-eluting stent is associated with net reductions in medical cost of $124 (Interquartile Range (IQR) $97-154) per patient in 2018 US$, of which $115 (IQR $76-124) accrues to the initial admission and $10 (IQR $7-72) to cost of follow-up. The lower rate of ppMI translates into a gain of 0.000017 (IQR 0.000011-0.000022) quality-adjusted life-years (QALY) per patient. CONCLUSIONS: Lower ppMI rates of bioresorbable polymer sirolimus-eluting stent translate into reductions in direct medical cost, while improving patient outcomes. Most of the cost reduction is attributed to the initial admission with moderate savings up to 12 months post-discharge.


Asunto(s)
Implantes Absorbibles/economía , Fármacos Cardiovasculares/administración & dosificación , Fármacos Cardiovasculares/economía , Enfermedad de la Arteria Coronaria/economía , Enfermedad de la Arteria Coronaria/terapia , Stents Liberadores de Fármacos/economía , Costos de la Atención en Salud , Intervención Coronaria Percutánea/economía , Intervención Coronaria Percutánea/instrumentación , Polímeros/economía , Sirolimus/administración & dosificación , Sirolimus/economía , Fármacos Cardiovasculares/efectos adversos , Ensayos Clínicos como Asunto , Simulación por Computador , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Enfermedad de la Arteria Coronaria/mortalidad , Ahorro de Costo , Análisis Costo-Beneficio , Costos de los Medicamentos , Everolimus/administración & dosificación , Everolimus/economía , Humanos , Cadenas de Markov , Modelos Económicos , Infarto del Miocardio/economía , Infarto del Miocardio/mortalidad , Infarto del Miocardio/terapia , Intervención Coronaria Percutánea/efectos adversos , Intervención Coronaria Percutánea/mortalidad , Diseño de Prótesis , Medición de Riesgo , Factores de Riesgo , Sirolimus/efectos adversos , Factores de Tiempo , Resultado del Tratamiento
15.
Anal Bioanal Chem ; 390(1): 89-111, 2008 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17989961

RESUMEN

Polymers have assumed the leading role as substrate materials for microfluidic devices in recent years. They offer a broad range of material parameters as well as material and surface chemical properties which enable microscopic design features that cannot be realised by any other class of materials. A similar range of fabrication technologies exist to generate microfluidic devices from these materials. This review will introduce the currently relevant microfabrication technologies such as replication methods like hot embossing, injection molding, microthermoforming and casting as well as photodefining methods like lithography and laser ablation for microfluidic systems and discuss academic and industrial considerations for their use. A section on back-end processing completes the overview.


Asunto(s)
Técnicas Analíticas Microfluídicas/instrumentación , Técnicas Analíticas Microfluídicas/métodos , Microfluídica/instrumentación , Microfluídica/métodos , Polímeros/síntesis química , Polímeros/economía , Propiedades de Superficie
16.
Cardiovasc Ther ; 36(5): e12442, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-29873191

RESUMEN

AIM: Compared with second-generation durable polymer drug-eluting stents (DP-DES), the cost-effectiveness of biodegradable polymer drug-eluting stents (BP-DES) remains unclear in the real-world setting. We assessed the cost-effectiveness of BP-DES in patients with coronary artery disease undergoing percutaneous coronary intervention (PCI). METHODS: We developed a decision-analytic model to compare the cost-effectiveness of BP-DES to DP-DES over 1 year and 5 years from healthcare payer perspective. Relative treatment effects during the first year post-PCI were obtained from a real-world population analysis while clinical event risks in the subsequent 4 years were derived from a meta-analysis of published studies. RESULTS: At 1 year, based on the clinical data analysis of 497 propensity-score matched pairs of patients, BP-DES were associated with an incremental cost-effectiveness ratio (ICER) of USD20 503 per quality-adjusted life-year (QALY) gained. At 5 years, BP-DES yielded an ICER of USD4062 per QALY gained. At the willingness-to-pay threshold of USD50 400 (one gross domestic product per capita in Singapore in 2015), BP-DES were cost-effective. Sensitivity analysis showed that the cost of stents had a significant impact on the cost-effectiveness of BP-DES. Threshold analysis demonstrated that if the cost difference between BP-DES and DP-DES exceeded USD493, BP-DES would not be cost-effective in patients with 1 year of follow-up. CONCLUSIONS: Biodegradable polymer drug-eluting stents were cost-effective compared with DP-DES in patients with coronary artery disease at 1 year and 5 years after PCI. It is worth noting that the cost of stents had a significant impact on the findings.


Asunto(s)
Implantes Absorbibles/economía , Enfermedad de la Arteria Coronaria/economía , Enfermedad de la Arteria Coronaria/terapia , Stents Liberadores de Fármacos/economía , Costos de la Atención en Salud , Intervención Coronaria Percutánea/economía , Polímeros/economía , Toma de Decisiones Clínicas , Enfermedad de la Arteria Coronaria/diagnóstico , Enfermedad de la Arteria Coronaria/mortalidad , Análisis Costo-Beneficio , Técnicas de Apoyo para la Decisión , Femenino , Humanos , Masculino , Persona de Mediana Edad , Modelos Económicos , Intervención Coronaria Percutánea/efectos adversos , Intervención Coronaria Percutánea/instrumentación , Intervención Coronaria Percutánea/mortalidad , Diseño de Prótesis , Años de Vida Ajustados por Calidad de Vida , Factores de Tiempo , Resultado del Tratamiento
17.
Pharmacoeconomics ; 36(12): 1463-1473, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30194623

RESUMEN

BACKGROUND AND OBJECTIVE: Certain patients with heart failure (HF) are unable to tolerate spironolactone therapy due to hyperkalemia. Patiromer is a novel agent used to treat hyperkalemia and has been shown to be efficacious, safe, and well-tolerated. The potential clinical outcomes and economic value of using patiromer and spironolactone in patients with HF unable to otherwise tolerate spironolactone due to hyperkalemia are unclear. The objective of this analysis was to model the potential pharmacoeconomic value of using patiromer and spironolactone in patients with a history of hyperkalemia that prevents them from utilizing spironolactone. METHODS: We performed a cost-effectiveness analysis of treatment with patiromer, spironolactone, and an angiotensin-converting enzyme inhibitor (ACEI) in patients with New York Heart Association (NYHA) class III-IV HF compared with ACEI alone. A Markov model was constructed to simulate a cohort of 65-year-old patients diagnosed with HF from the payer perspective across the lifetime horizon. Clinical inputs were derived from the RALES and OPAL-HK randomized trials of spironolactone and patiromer, respectively. Utility estimates and costs were derived from the literature and list prices. Outcomes assessed included hospitalization, life expectancy, and quality-adjusted life-years (QALYs), costs, and the incremental cost-effectiveness ratio (ICER). One-way and probability sensitivity analyses were performed to test the robustness of the model findings. RESULTS: Treatment with patiromer-spironolactone-ACEI was projected to increase longevity compared with ACEI alone (5.29 vs. 4.62 life-years gained, respectively), greater QALYs (2.79 vs. 2.60), and costs (US$28,200 vs. US$18,200), giving an ICER of US$52,700 per QALY gained. The ICERs ranged from US$40,000 to US$85,800 per QALY gained in 1-way sensitivity analyses. CONCLUSION: Our results suggest that the use of spironolactone-patiromer-ACEI may provide clinical benefit and good economic value in patients with NYHA class III-IV HF unable to tolerate spironolactone due to hyperkalemia.


Asunto(s)
Insuficiencia Cardíaca/tratamiento farmacológico , Hiperpotasemia/tratamiento farmacológico , Polímeros/administración & dosificación , Espironolactona/administración & dosificación , Anciano , Análisis Costo-Beneficio , Diuréticos/administración & dosificación , Diuréticos/economía , Economía Farmacéutica , Insuficiencia Cardíaca/complicaciones , Insuficiencia Cardíaca/economía , Hospitalización/economía , Humanos , Hiperpotasemia/economía , Hiperpotasemia/etiología , Cadenas de Markov , Polímeros/economía , Años de Vida Ajustados por Calidad de Vida , Ensayos Clínicos Controlados Aleatorios como Asunto , Espironolactona/economía , Resultado del Tratamiento
18.
Nefrología (Madrid) ; 43(6): 721-730, nov.- dec. 2023. tab, graf
Artículo en Español | IBECS (España) | ID: ibc-228010

RESUMEN

Introducción La hiperpotasemia crónica tiene consecuencias negativas a medio y largo plazo, condicionando generalmente la suspensión de fármacos nefro y cardioprotectores, en pacientes con enfermedad renal crónica (ERC) e insuficiencia cardíaca (IC), como son los inhibidores del sistema renina-angiotensina-aldosterona. Existe una alternativa a la suspensión o reducción de dosis de estos tratamientos y es la administración de quelantes del potasio. El objetivo de este estudio es estimar el impacto económico que supondría el uso de patiromer en pacientes con ERC o IC e hiperpotasemia en España. Material y métodos Se ha estimado el impacto económico anual del uso de patiromer desde la perspectiva de la sociedad española, comparando 2 escenarios: pacientes con ERC o IC e hiperpotasemia tratada con patiromer y sin patiromer. Los costes se han actualizado a euros de 2020, utilizando el índice de precios de consumo de Sanidad. Se han considerado los costes directos sanitarios relacionados con el uso de recursos (el tratamiento con inhibidores del sistema renina-angiotensina-aldosterona, la progresión de la ERC, los eventos cardiovasculares y la hospitalización por hiperpotasemia), los costes directos no sanitarios (cuidados informales: costes derivados del tiempo de dedicación por parte de los familiares del paciente), los costes indirectos (pérdidas de productividad laboral), así como un coste intangible (por mortalidad prematura). Se realizó un análisis de sensibilidad determinístico para validar la consistencia de los resultados del estudio. Resultados El coste medio anual por paciente en el escenario sin patiromer es de 9.834,09 € y 10.739,37 € en ERC e IC, respectivamente. El uso de patiromer supondría un ahorro de costes superior al 30% en ambas enfermedades. En el caso de la ERC, el mayor ahorro procede del retraso de la progresión de la ERC (AU)


Introduction Chronic hyperkalemia has negative consequences in the medium and long term, and determines the suspension of nephro and cardioprotective drugs, such as renin–angiotensin–aldosterone system inhibitors (RAASi). There is an alternative to the suspension or dose reduction of these treatments: the administration of potassium chelators. The aim of this study is to estimate the economic impact of the use of patiromer in patients with chronic kidney disease (CKD) or heart failure (HF) and hyperkalemia in Spain. Materials and method The annual economic impact of the use of patiromer has been estimated from the perspective of the Spanish society. Two scenarios were compared: patients with CKD or HF and hyperkalemia treated with and without patiromer. The costs have been updated to 2020 euros, using the Health Consumer Price Index. Direct healthcare costs related to the use of resources (treatment with RAASi, CKD progression, cardiovascular events and hospitalization due to hyperkalemia), direct non-healthcare costs (informal care: costs derived from time dedicated by patient's relatives), the indirect costs (productivity loss), as well as an intangible cost (due to premature mortality) were considered. A deterministic sensitivity analysis was performed to validate the robustness of the study results. Results The mean annual cost per patient in the scenario without patiromer is €9834.09 and €10,739.37 in CKD and HF, respectively. The use of patiromer would lead to cost savings of over 30% in both diseases. The greatest savings in CKD come from the delay in the progression of CKD. While in the case of HF, 80.1% of these savings come from premature mortality reduction. The sensitivity analyses carried out show the robustness of the results, obtaining savings in all cases (AU)


Asunto(s)
Humanos , Masculino , Femenino , Insuficiencia Renal Crónica/terapia , Insuficiencia Cardíaca/terapia , Hiperpotasemia/tratamiento farmacológico , Costos de la Atención en Salud , Polímeros/administración & dosificación , Polímeros/economía , Inhibidores de la Enzima Convertidora de Angiotensina/administración & dosificación , Inhibidores de la Enzima Convertidora de Angiotensina/economía
19.
Bioresour Technol ; 224: 581-589, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27839861

RESUMEN

Poly(ß-l-malic acid) (PMA) is a biodegradable polymer with many potential biomedical applications. PMA can be readily hydrolyzed to malic acid (MA), which is widely used as an acidulant in foods and pharmaceuticals. PMA production from sucrose and sugarcane juice by Aureobasidium pullulans ZX-10 was studied in shake-flasks and bioreactors, confirming that sugarcane juice can be used as an economical substrate without any pretreatment or nutrients supplementation. A high PMA titer of 116.3g/L and yield of 0.41g/g were achieved in fed-batch fermentation. A high productivity of 0.66g/L·h was achieved in repeated-batch fermentation with cell recycle. These results compared favorably with those obtained from glucose and other biomass feedstocks. A process economic analysis showed that PMA could be produced from sugarcane juice at a cost of $1.33/kg, offering a cost-competitive bio-based PMA for industrial applications.


Asunto(s)
Ascomicetos/metabolismo , Biotecnología/métodos , Malatos/economía , Malatos/metabolismo , Polímeros/economía , Polímeros/metabolismo , Saccharum/metabolismo , Técnicas de Cultivo Celular por Lotes , Biomasa , Reactores Biológicos , Biotecnología/economía , Biotecnología/instrumentación , Fermentación , Glucosa/metabolismo , Cinética , Saccharum/química , Sacarosa/metabolismo
20.
J Cardiovasc Surg (Torino) ; 47(2): 161-70, 2006 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-16572090

RESUMEN

AIM: We designed a study to estimate the economic impact of CoSeal Surgical Sealant for the prevention of anastomotic bleeding in cardiac and vascular surgery. We also explored the potential economic value of CoSeal as a means of inhibiting the formation of pericardial tissue adhesions. METHODS: A Delphi panel of 6 expert vascular and cardiac surgeons provided the assumptions and estimates needed to develop a decision analysis model to assess the impact of sealant on the costs associated with low- and high-risk forms of cardiac (valve replacement/reconstruction) and vascular (abdominal aortic aneurysm [AAA] repair, femoral bypass grafting) surgery. The primary outcome was incremental cost per patient. RESULTS: For valve repair/replacement surgery, sealant was expected to confer cost-savings in high-risk but not low-risk procedures. Predicted cost savings for high-risk AAA repairs were substantial, but minimal in the overall AAA group. Cost-savings were predicted for sealant use in all femoral-popliteal ePTFE bypass grafts, but in high-risk femoral-femoral ePTFE bypass grafts only. CONCLUSIONS: According to our decision analysis model, routine use of surgical sealant in select subgroups may confer considerable economic benefits to health service budgets. Future research should aim at testing this model in a real-world hospital setting. Assessment of the value of CoSeal in the prevention of postsurgical adhesions showed that expert surgeons see a need for effective prophylaxis. Further research into the clinical and economic benefit of this intervention is required.


Asunto(s)
Pérdida de Sangre Quirúrgica/prevención & control , Procedimientos Quirúrgicos Cardiovasculares/efectos adversos , Técnicas de Apoyo para la Decisión , Hemostasis Quirúrgica/economía , Polietilenglicoles/economía , Adhesivos Tisulares/economía , Anastomosis Quirúrgica/efectos adversos , Análisis Costo-Beneficio , Humanos , Polímeros/economía , Adherencias Tisulares/etiología , Adherencias Tisulares/prevención & control
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