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1.
Mol Genet Genomics ; 299(1): 49, 2024 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-38704518

RESUMO

The main objective of this study was to determine whether the common Y-haplogroups were be associated with the risk of developing severe COVID-19 in Spanish male. We studied 479 patients who required hospitalization due to COVID-19 and 285 population controls from the region of Asturias (northern Spain), They were genotyped for several polymorphisms that define the common European Y-haplogroups. We compared the frequencies between patients and controls aged ≤ 65 and >65 years. There were no different haplogroup frequencies between the two age groups of controls. Haplogroup R1b was less common in patients aged ≤65 years. Haplogroup I was more common in the two patient´s groups compared to controls (p = 0.02). Haplogroup R1b was significantly more frequent among hypertensive patients, without difference between the hypertensive and normotensive controls. This suggested that R1b could increase the risk for severe COVID-19 among male with pre-existing hypertension. In conclusion, we described the Y-haplogroup structure among Asturians. We found an increased risk of severe COVID-19 among haplogroup I carriers, and a significantly higher frequency of R1b among hypertensive patients. These results indicate that Y-chromosome variants could serve as markers to define the risk of developing a severe form of COVID-19.


Assuntos
COVID-19 , Cromossomos Humanos Y , Haplótipos , Hipertensão , SARS-CoV-2 , Humanos , Masculino , COVID-19/genética , COVID-19/epidemiologia , Espanha/epidemiologia , Haplótipos/genética , Idoso , Pessoa de Meia-Idade , SARS-CoV-2/genética , Cromossomos Humanos Y/genética , Hipertensão/genética , Predisposição Genética para Doença , Estudos de Casos e Controles , Polimorfismo de Nucleotídeo Único , Adulto , Feminino
2.
Ann Hematol ; 103(2): 583-591, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37923805

RESUMO

Although it is known that increasing age is associated with increased morbidity and mortality in allogeneic transplantation (allo-HSCT), individualization of the process may allow to perform it in progressively older patients.This study analyzed the outcome of 97 patients older than 60 years with a first allo-HSCT performed at our institution between 2011 and 2019.Median age was 66 years (range 60-79) and 15.4% were older than 70 years. The most frequent diagnosis was acute leukemia (50.5%), and 58.8% received a myeloablative conditioning. With a median follow-up of 33.9 months (range 7.9-111.5), at 3-years overall survival (OS) was 50%; progression-free survival (PFS), 46%; cumulative incidence of relapse, 22%; and non-relapse mortality (NRM), 32%. There were no significant differences in OS (p = 0.415), PFS (p = 0.691), cumulative incidence of relapse (p = 0.357) or NRM (p = 0.658) between patients of 60-64 years (n = 37), 65-69 (n = 45) and ≥ 70 years (n = 15). No differences were observed either depending on the intensity of the conditioning regimen in terms of OS (p = 0.858), PFS (p = 0.729), cumulative incidence of relapse (p = 0.416) or NRM (p = 0.270).In conclusion, older adults can safely and effectively undergo allo-HSCT with proper patient selection and individualized transplantation procedures.


Assuntos
Doença Enxerto-Hospedeiro , Transplante de Células-Tronco Hematopoéticas , Leucemia Mieloide Aguda , Humanos , Idoso , Pessoa de Meia-Idade , Estudos de Viabilidade , Estudos Retrospectivos , Leucemia Mieloide Aguda/complicações , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Recidiva , Condicionamento Pré-Transplante/métodos , Doença Enxerto-Hospedeiro/etiologia
3.
J Clin Med ; 12(6)2023 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-36983136

RESUMO

Mitochondrial DNA (mtDNA) differs from the nuclear genome in many aspects: a maternal inheritance pattern; being more prone to acquire somatic de novo mutations, accumulative with age; and the possible coexistence of different mtDNA alleles (heteroplasmy). Mitochondria are key cellular organelles responsible for energy production and involved in complex mechanisms, including atherosclerosis. In this scenario, we aimed to evaluate mtDNA variants that could be associated with premature cardiovascular disease. We evaluated 188 consecutive patients presenting with premature myocardial infarction with ST elevation (STEMI) confirmed by coronary angiogram. mtDNA polymorphisms and clinical data were evaluated and compared with 271 individuals from the same population (control group). Tobacco consumption (80.85% vs. 21.21%, p < 0.01) and dyslipidemia (38.83% vs. 28.41%, p = 0.02) were significantly more frequent among STEMI patients. Moreover, C16223T mtDNA mutation and poly-C heteroplasmy were significantly more frequent among premature STEMI male patients than in controls. The OR associated C16223T mtDNA with the increased presence of cardiovascular risk factors. Our data suggest that mtDNA 16223T and heteroplasmy may be associated with unstable premature atherosclerosis disease in men. Moreover, the presence of cardiovascular risk factors (CVRFs) was associated with C16223T mtDNA, with a cumulative effect. Protective mitochondrial pathways are potential therapeutic targets. Preventing exposure to the damaging mechanisms associated with CVRFs is of utmost importance.

4.
Pain Pract ; 20(2): 138-146, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31505094

RESUMO

The fascia is an undifferentiated mesenchymal tissue related to the peripheral nerves. Both can be identified by ultrasound, which is useful when performing peripheral nerve blocks. However, there is no unanimity about the approaching point of each nerve, nor is there a consensus on how to name the appropriate infiltration zone, although the paraneural zone is frequently mentioned. The aims of this study were to determine if ultrasound is accurate for identifying the fascial planes and the paraneural space of the nerves in the knee, infiltrating them, and achieving a correct anatomical diffusion, as well as for establishing access routes to avoid intraneural infiltration. The study was performed in 16 cryopreserved lower extremities of the dissection room of the Faculty of Medicine and Health Sciences, University of Barcelona. Nerves of the knee were injected with colorant guided by ultrasound after they were visualized. Correct location of the nerves by ultrasound was achieved in 98.75% of the cases, correct visualization of the needle by ultrasound in 82.5%, the hypoechogenic image around the nerve after infiltration in 82.5%, and a correct paraneural infiltration in 76.25% of cases. With these results, we can conclude that high-definition ultrasound enables location of the peripheral nerves and adjacent structures as well as the fasciae that surround them, and therefore allows performance of infiltrations in the paraneural spaces.


Assuntos
Fáscia/diagnóstico por imagem , Articulação do Joelho/diagnóstico por imagem , Nervos Periféricos/diagnóstico por imagem , Ultrassonografia de Intervenção/métodos , Anestesia por Condução/métodos , Fáscia/anatomia & histologia , Humanos , Injeções , Articulação do Joelho/anatomia & histologia , Agulhas , Bloqueio Nervoso/métodos , Nervos Periféricos/anatomia & histologia
5.
Metas enferm ; 22(3): 12-19, abr. 2019.
Artigo em Espanhol | IBECS | ID: ibc-183525

RESUMO

Objetivo: explorar las características y comportamientos que comparten las chicas pro-ANA (anorexia nerviosa en entornos virtuales), así como identificar sus necesidades de salud. Método: investigación cualitativa basada en el análisis en profundidad de cuatro blogs pro-ANA, que se llevó a cabo en dos fases. En una primera fase exploratoria se desarrolló la selección, vaciado y análisis de los blogs pro-ANA; posteriormente se elaboró un blog propio, "Un cambio de rumbo", para interaccionar y acercarse a las participantes de estudio. En la segunda fase se hizo un análisis intensivo sobre la transcripción de los blogs y se elaboró un diario de campo de cada uno, que fue utilizado como herramienta para efectuar la codificación y categorización. Resultados: fueron obtenidas las siguientes categorías: búsqueda de la perfección y preocupación por el peso y la imagen; fotografías thinspiration autoestima baja y búsqueda de reconocimiento social; meta de peso, autoinsultos, sentimientos de culpa, vacío, soledad e incomprensión; autocontrol sobre el cuerpo; autoexigencia, conflicto familiar y humor lábil; autolesiones; mentiras y doble personalidad; TCA como estilo de vida; contradicciones conciencia de enfermedad; y evasión y búsqueda de apoyo en el mundo de los blogs. Conclusiones: a pesar del intento por parte de las participantes de alcanzar el éxito en todas las esferas de la vida diaria a través de la delgadez se establece en ellas un sentimiento de insatisfacción personal y de baja autoestima, que aumenta paralelamente junto con la instauración del trastorno. La autoestima se convierte en el eje vertebrador de todos los aspectos que giran en torno a dicho trastorno


Objective: to explore the characteristics and behaviors shared by Pro-ANA girls (anorexia nervosa in virtual settings), as well as to identify their health needs. Method: a qualitative research based on the in-depth analysis of Pro-ANA blogs, conducted in two stages. The first exploratory stage consisted in the selection, data collection and analysis of the Pro-ANA blogs; subsequently, a specific blog was prepared, called "A change in direction", in order to interact with and get close to the study participants. In the second stage, an intensive analysis was conducted on the blog transcription, and a field journal was prepared for each one, which was used as a tool for coding and classification. Results: the following categories were retrieved: the search for perfection and concern with weight and image; "thinspiration" photos, low self-esteem and search for social acknowledgement; weight goals, self-insults; feelings of guilt, emptiness, loneliness and incomprehension; self-control over the body; self-demand, family conflicts and labile mood; self-lesions; lies and double personality; eating disorders as a lifestyle; contradictions, disease awareness; and escape and search for support in the world of blogs. Conclusions: regardless of the attempt by the participants to reach success in all daily life areas through thinness, a feeling of personal dissatisfaction and low self-esteem gets hold of them, which increases in parallel with the implementation of the disorder. Self-esteem becomes the main axis for all aspects revolving around said disorder


Assuntos
Humanos , Feminino , Adolescente , Adulto Jovem , Adulto , Anorexia Nervosa/epidemiologia , Anorexia Nervosa/prevenção & controle , Transtornos da Alimentação e da Ingestão de Alimentos/epidemiologia , Estilo de Vida , Anorexia Nervosa/psicologia , Transtornos da Alimentação e da Ingestão de Alimentos/prevenção & controle , Transtornos da Alimentação e da Ingestão de Alimentos/psicologia , Pesquisa Qualitativa , Blogging , Autoimagem , Autocontrole , Comportamento Autodestrutivo
6.
Ophthalmic Surg Lasers Imaging Retina ; 49(9): e105-e111, 2018 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-30222829

RESUMO

BACKGROUND AND OBJECTIVE: To evaluate anatomical changes of idiopathic macular hole (MH) after internal limiting membrane removal and after passive suction at the hole's borders using microscope-integrated intraoperative optical coherence tomography (iOCT). PATIENTS AND METHODS: Five eyes of five subjects with full-thickness idiopathic MH underwent phacoemulsification, intraocular lens implantation, pars plana vitrectomy, and internal limiting membrane (ILM) removal. iOCT was performed after ILM removal and after passive suction at the hole's borders. RESULTS: iOCT showed decreased MH diameter after ILM removal in all cases. Passive suction achieved complete apposition of borders. All cases presented successful postsurgical closure. CONCLUSIONS: iOCT provides anatomical information during MH surgery that may impact surgical decision-making by allowing a real-time evaluation of structures. iOCT with preservative-free triamcinolone acetonide enhanced ILM visualization. Its use is superior to iOCT alone for the identification of vitreomacular interface structures. [Ophthalmic Surg Lasers Imaging Retina. 2018;49:e105-e111.].


Assuntos
Membrana Epirretiniana/cirurgia , Perfurações Retinianas/diagnóstico por imagem , Tomografia de Coerência Óptica/métodos , Tamponamento Interno , Feminino , Humanos , Implante de Lente Intraocular , Masculino , Microscopia , Pessoa de Meia-Idade , Facoemulsificação , Perfurações Retinianas/cirurgia , Vitrectomia/métodos
8.
Macromol Biosci ; 16(3): 395-411, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26632009

RESUMO

The aim of this work is the preparation of an active nanovehicle for the effective administration of α-tocopheryl succinate (α-TOS). α-TOS is loaded in the core of nanoparticles (NPs) based on amphiphilic pseudo-block copolymers of N-vinyl pyrrolidone and a methacrylic derivative of α-TOS. These well-defined spherical NPs have sizes below 165 nm and high encapsulation efficiencies. In vitro activity of NPs is tested in hypopharynx squamous carcinoma (FaDu) cells and nonmalignant epithelial cells, demonstrating that the presence of additional α-TOS significantly enhances its antiproliferative activity; however, a range of selective concentrations is observed. These NPs induce apoptosis of FaDu cells by activating the mitochondria death pathway (via caspase-9). Both loaded and unloaded NPs act via complex II and produce high levels of reactive oxygen species that trigger apoptosis. Additionally, these NPs effectively suppress the vascular endothelial growth factor (VEGF) expression of human umbilical vein endothelial cells (HUVECs). These results open the possibility to use this promising nanoformulation as an α-TOS delivery system for the effective cancer treatment, effectively resolving the current limitations of free α-TOS administration.


Assuntos
Apoptose/efeitos dos fármacos , Carcinoma de Células Escamosas/tratamento farmacológico , Sistemas de Liberação de Medicamentos/métodos , Neoplasias Hipofaríngeas/tratamento farmacológico , Mitocôndrias/metabolismo , Nanopartículas/química , Pirrolidinonas , alfa-Tocoferol , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , Caspase 9/metabolismo , Humanos , Neoplasias Hipofaríngeas/metabolismo , Neoplasias Hipofaríngeas/patologia , Mitocôndrias/patologia , Nanopartículas/ultraestrutura , Proteínas de Neoplasias/metabolismo , Pirrolidinonas/química , Pirrolidinonas/farmacologia , alfa-Tocoferol/química , alfa-Tocoferol/farmacologia
9.
Rev Psiquiatr Salud Ment ; 2(4): 160-8, 2009 Oct.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-23034345

RESUMO

INTRODUCTION: The Positive and Negative Syndrome Scale (PANSS) is a widely used instrument for measuring symptomatology in patients with schizophrenia. Numerous studies have analyzed the factorial structure of this scale and have suggested a fivefactor model, namely: negative, positive, excited, anxiety/depression, and disorganized (or cognitive). The latter factor has been related to neuropsychological tests, with a view to analyzing its utility as a measure of cognitive functioning in schizophrenia, but data are inconclusive. The aim of the present study was to analyze the factorial structure of the PANSS and to assess the relationships between factors and neurocognitive tests. MATERIAL AND METHODS: The sample comprised 235 outpatients diagnosed with schizophrenia. To investigate the factorial structure of the PANSS, a principal component factor analysis was performed. Cognitive functioning was measured with a shortened version of the Barcelona Test. RESULTS: Unlike previous studies, our study obtained a six-factor model, with disorganized and cognitive symptoms separated in two different factors. The cognitive factor obtained in this study was related to all subtests of the Barcelona Test. The disorganized factor, however, was only related to two of these subtests. CONCLUSIONS: Our results support the use of a six-factor model and suggest that the cognitive factor could be a valid measure of cognitive deficits in schizophrenia, although the use of a standard neuropsychological battery is advisable.

10.
J Tissue Eng Regen Med ; 1(2): 120-7, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-18038400

RESUMO

New injectable acrylic formulations have been prepared to be applied in restoration processes for intervertebral disks (IVDs). The solid phase of the formulations is composed of poly(methyl methacrylate) (PMMA), incorporating in some cases chondroitin sulphate (CS) as a regenerative bioactive molecule, whereas the liquid phase is constituted by an amphiphilic macromonomer (MT), 2-hydroxyethyl methacrylate (HEMA) and, in some formulations, acrylic acid (AA). The curing parameters and the mechanical properties of the IVD formulations make them excellent candidates for intervertebral application. In vitro and in vivo evaluation of the prepared IVD formulations is described in terms of CS release, surface analysis after immersion in SBF solutions, and biocompatibility studies based on MTT assay and Alamar blue test, as well as in vivo implantation in female Wistar rats, by injection of the IVD formulations followed by histological evaluations to assess tissue response.


Assuntos
Acrilatos , Condroitina/farmacologia , Disco Intervertebral/efeitos dos fármacos , Cicatrização/efeitos dos fármacos , Animais , Química Farmacêutica , Chlorocebus aethiops , Feminino , Disco Intervertebral/cirurgia , Microscopia Eletrônica de Varredura , Ratos , Ratos Wistar , Células Vero
11.
J Mater Sci Mater Med ; 18(9): 1719-26, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17483900

RESUMO

Films and sponges of chitosan (CHI), chitosan/hyaluronic acid (CHI-HA) and chitosan/chondroitin sulphate (CHI-CHOS), were prepared by film deposition or lyophilization (sponges), avoiding the formation of interpolyelectrolyte complexes. The biological behaviour of the systems was analysed by studying the cell behaviour using a fibroblast cell line and standard biological MTT and Alamar Blue tests. The morphology of films, sponges and cell seeded samples was analysed by ESEM. The results obtained indicate that all the systems can be considered as good supports for cell adhesion and proliferation, but there is specific activation of the proliferative process in the presence of hyaluronic acid and chondroitin sulphate.


Assuntos
Materiais Biocompatíveis/química , Quitosana/química , Sulfatos de Condroitina/química , Ácido Hialurônico/química , Sequência de Carboidratos , Adesão Celular , Linhagem Celular , Proliferação de Células , Humanos , Teste de Materiais , Microscopia Eletrônica de Varredura , Dados de Sequência Molecular , Estrutura Molecular
12.
Biomaterials ; 27(1): 100-7, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16009418

RESUMO

One of the problems of percutaneous vertebroplasty attributed to the use of acrylic cements is related to the radiopacity of the formulation. The use of bismuth salicylate as the radiopaque agent is proposed in this work, taking into account the high radiopacity of organobismuth compounds used in dental applications and the possible analgesic effect of salicylic acid. Various cements formulated with this compound (some of them modified with polyethylene oxide) were examined. Setting parameters, mechanical properties, rheological behaviour, injectability, radiopacity and biocompatibility were studied for a variety of formulations, showing that the cement formulations containing bismuth salicylate have a higher radiopacity and better injection properties than commercial bone cement preparations and present good mechanical properties.


Assuntos
Materiais Biocompatíveis/química , Cimentos Ósseos/química , Polimetil Metacrilato/química , Polimetil Metacrilato/farmacologia , Salicilatos/farmacologia , Ácido Salicílico/química , Coluna Vertebral/patologia , Substitutos Ósseos/química , Meios de Contraste/farmacologia , Teste de Materiais , Tamanho da Partícula , Polietilenoglicóis/química , Reologia , Estresse Mecânico , Temperatura , Resistência à Tração , Fatores de Tempo , Raios X
13.
Biomaterials ; 26(16): 3311-8, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15603826

RESUMO

An injectable delivery system for prednisolone has been prepared based on a self-curing formulation comprised of poly(methyl methacrylate) particles and hydroxyethyl methacrylate as monomer. The polymerisation reaction was initiated by the redox system 4,4'-bis (dimethylaminobenzydrol)/benzoyl peroxide (BZN/BPO) and followed at 25 degrees C by measuring the time-temperature profile. A maximum temperature of 53 degrees C and a setting time of 15 min were obtained, calculated according to standard specifications. The swelling of the cured system was studied in phosphate-buffered saline (PBS) at 37 degrees C giving a hydration degree at equilibrium of 20%. The swelling kinetics fitted a fickian behaviour at the initial stages of the experiments, with a diffusion coefficient of 0.72 x 10(-7) cm2/s. The release of the drug was sustained from the beginning without an initial drug burst. The study of the wettability showed a rather hydrophilic character of the surface of the loaded system, and the biocompatibility evaluated through MTT assay revealed the absence of cytotoxicity due to the release of toxic substances.


Assuntos
Materiais Biocompatíveis/química , Portadores de Fármacos , Otopatias/tratamento farmacológico , Glucocorticoides/administração & dosagem , Prednisolona/administração & dosagem , Esteroides/administração & dosagem , Animais , Peróxido de Benzoíla/química , Corantes/farmacologia , Difusão , Sistemas de Liberação de Medicamentos , Glucocorticoides/farmacologia , Humanos , Cinética , Metilmetacrilatos/química , Microscopia Eletrônica , Modelos Químicos , Oxirredução , Polímeros , Polimetil Metacrilato/química , Prednisolona/farmacologia , Temperatura , Sais de Tetrazólio/farmacologia , Tiazóis/farmacologia , Fatores de Tempo
14.
15.
Crash test ; (68): 24-28, 2005. ilus, tab
Artigo em Espanhol | BINACIS | ID: biblio-1161435
16.
Macromol Biosci ; 4(6): 579-86, 2004 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-15468251

RESUMO

Hydrophilic polymeric drugs bearing "Triflusal" (4-trifluoromethylsalicylic acid), a drug widely used as antithrombogenic agent (Disgren), have been prepared by free radical copolymerization of methacryloyloxyethyl [2-(acetyloxy)-4-(trifluoromethyl)] benzoate (HTRF) and N,N'-dimethylacrylamide (DMA). The reactivity ratios of both monomers have been determined by 1H NMR spectra by applying non-linear least square treatments to the copolymerization equation (terminal model), and the kinetic parameters obtained indicated that the microstructure of copolymer chains is homogeneous, with a random distribution of the active HTRF units along the copolymer chains. That means that for the copolymer system THDMA22 used in this work, HTRF units are mainly isolated in relatively long DMA sequences. Therefore, in this structure the intramolecular interactions between adjacent HTRF units are negligible. Release of Triflusal from THDMA22 has been studied in vitro using buffered solutions at pH = 2, 7.4 and 10 and 37 degrees C. The system showed an interesting pseudo-zero order release profile at pH = 7.4 during several months. It has been also evaluated the pharmacological activity and the behavior of the system in contact with biological media. In this sense, we have carried out some in vitro studies about the antiaggregant properties and biocompatibility of THDMA22. Results demonstrate that this copolymer inhibits platelet aggregation in its macromolecular form and presents a good biocompatibility with Human Osteoblastic Cells (HOS).


Assuntos
Preparações Farmacêuticas/síntese química , Polímeros/síntese química , Ácido Salicílico/química , Humanos , Concentração de Íons de Hidrogênio , Espectroscopia de Ressonância Magnética , Teste de Materiais , Osteoblastos/efeitos dos fármacos , Agregação Plaquetária/efeitos dos fármacos , Polímeros/química , Polímeros/farmacologia
17.
J Control Release ; 99(2): 231-40, 2004 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-15380633

RESUMO

Poly(methyl methacrylate), PMMA, and of PMMA/Poly(epsilon-caprolactone), PCL, microspheres were loaded with different amounts of cholesterol by using a supercritical carbon dioxide (SC-CO2) impregnation process in order to use a clean technique with the absence of organic solvents, and to provide information for the infusion of additives into nonporous polymeric substrates. A conventional dissolution-evaporation method was also used to obtain PMMA and PMMA-PCL microparticles loaded with cholesterol. The obtained microspheres were characterized by environmental scanning electronic microscope, ESEM, nuclear magnetic resonance spectroscopy, NMR, and differential scanning calorimetry, DSC, thermal analysis. A comparison of drug release from particles obtained using both methods, the supercritical and the conventional, is presented.


Assuntos
Dióxido de Carbono/farmacocinética , Colesterol/química , Sistemas de Liberação de Medicamentos/métodos , Microesferas , Poliésteres/química , Polimetil Metacrilato/química , Varredura Diferencial de Calorimetria/métodos , Dióxido de Carbono/química , Química Farmacêutica/instrumentação , Química Farmacêutica/métodos , Colesterol/farmacocinética , Sistemas de Liberação de Medicamentos/tendências , Estudos de Avaliação como Assunto , Excipientes/química , Excipientes/farmacocinética , Espectroscopia de Ressonância Magnética/métodos , Microscopia Eletrônica de Varredura/métodos , Tamanho da Partícula , Poliésteres/farmacocinética , Polimetil Metacrilato/farmacocinética , Solubilidade , Soluções/química , Soluções/farmacocinética , Espanha , Tecnologia Farmacêutica/instrumentação , Tecnologia Farmacêutica/métodos , Termodinâmica , Volatilização
18.
J Biomater Sci Polym Ed ; 15(7): 917-28, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15318801

RESUMO

The in vitro aqueous behaviour of a metacryloyloxyethyl [2-(acetyloxy)-4-(trifluoromethyl)]benzoate (THEMA)/N,N'-dimethylacrylamide (DMA) copolymer with a THEMA molar content of 39% (labeled THDMA39) has been investigated. This composition has been selected to achieve a system able to keep both the non-water solubility during the release and the resorbability (and the water solubility) after the completion of the drug release. This copolymer exhibited, at pH 7.4, a constant release during several months, very interesting for a long term treatments required for the application of some cardiovascular devices. A kinetic model has been developed to explain the pseudo-zero-order kinetics of the release process. This model, which considers (from the aqueous studies) a linear increase with time of the amount of water present in the polymeric matrix, has been able to fit adequately the experimental data.


Assuntos
Materiais Biocompatíveis/química , Plaquetas/efeitos dos fármacos , Desenho de Fármacos , Inibidores da Agregação Plaquetária/farmacologia , Agregação Plaquetária/efeitos dos fármacos , Polímeros/química , Tolueno/análogos & derivados , Acrilamidas/química , Radicais Livres , Humanos , Concentração de Íons de Hidrogênio , Hidrólise , Cinética , Espectroscopia de Ressonância Magnética , Modelos Químicos , Inibidores da Agregação Plaquetária/farmacocinética , Salicilatos/química , Trombina/química , Fatores de Tempo , Tolueno/química , Água/química
19.
J Mater Sci Mater Med ; 13(12): 1099-104, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15348650

RESUMO

Copolymers containing functional groups with activity as antiaggregating agents for platelets, based on random chains of metacryloyloxyethyl [2-(acetyloxy)-4-(trifluoromethyl)]benzoate, TH, and 2-acrylamido-2-metylpropanesulfonic acid, AMPS, with AMPS molar fractions ranging from 0.1 to 0.4, have been prepared. The spectroscopical characterization and the in vitro swelling behavior have been studied, as well as the surface free energy, showing the copolymers an appropriate surface properties from a haemocompatible point of view. Preliminary in vitro tests using human blood have shown a promising antiaggregating behavior.

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