Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 39
Filtrar
Más filtros

Tipo del documento
Intervalo de año de publicación
1.
Pharm Dev Technol ; 24(8): 1044-1053, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31180272

RESUMEN

Three-dimensional (3D) printing technologies are manufacturing approaches with widespread use in industry (e.g. automotive, automobile, pharmaceutical industries). With regard to its use in pharmaceutical industry, 3D printing is demonstrating to be of added value attributed to the possibility of printing tailored pharmaceutical products, namely personalized medical devices, such as implants and other dosage forms. However, with the approval of the first 3D-printed drug-product in 2015, a new perspective has arisen, i.e. the use of this technology to produce solid oral dosage forms exhibiting complex drug release profiles and allowing for individual dosing. Technological hurdles and regulatory issues still have to be overcome before this technology can truly find its place in the healthcare sector, where it can certainly contribute to a personalized and patient-centered healthcare. This manuscript offers a comprehensive analysis of the most extensively used methods of 3D printing in the pharmaceutical field, with examples of solid oral dosage forms and other medical devices currently under development or already marketed.


Asunto(s)
Preparaciones Farmacéuticas/química , Tecnología Farmacéutica/métodos , Formas de Dosificación , Industria Farmacéutica/métodos , Liberación de Fármacos , Impresión Tridimensional , Prótesis e Implantes
2.
Ecotoxicology ; 24(9): 1896-905, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26298705

RESUMEN

Currently diverse biocidal agents can be used for distinct applications, such as personal hygiene, disinfection, antiparasitic activity, and antifouling effects. Zinc pyrithione is an organometallic biocide, with bactericidal, algicidal and fungicidal activities. It has been recently incorporated in antifouling formulas, such as paints, which prevent the establishment of a biofilm on surfaces exposed to the aquatic environment. It has also been used in cosmetics, such as anti-dandruff shampoos and soaps. Previously reported data has shown the presence of this substance in the aquatic compartment, a factor contributing to the potential exertion of toxic effects, and there is also evidence that photodegradation products of zinc pyrithione were involved in neurotoxic effects, namely by inhibiting cholinesterases in fish species. Additional evidence points to the involvement of zinc pyrithione in alterations of metal homeostasis and oxidative stress, in both aquatic organisms and human cell models. The present work assesses the potential ecotoxicity elicited by zinc pyrithione in the freshwater fish Gambusia holbrooki after an acute (96 h) exposure. The oxidative stress was assessed by the quantification of the activities of specific enzymes from the antioxidant defense system, such as catalase, and glutathione-S-transferases; and the extent of peroxidative damage was quantified by measuring the thiobarbituric acid reactive substances levels. Neurotoxicity was assessed through measurement of acetylcholinesterase activity; and a standardized method for the description and assessment of histological changes in liver and gills of was also used. Zinc pyrithione caused non-specific and reversible tissue alterations, both in liver and gills of exposed organisms. However, histopathological indices were not significantly different from the control group. In terms of oxidative stress biomarkers, none of the tested biomarkers indicated the occurrence of pro-oxidative effects, suggesting that the oxidative pathway is not the major toxicological outcome of exposure to zinc pyrithione.


Asunto(s)
Ciprinodontiformes/metabolismo , Compuestos Organometálicos/toxicidad , Piridinas/toxicidad , Contaminantes Químicos del Agua/toxicidad , Animales , Antioxidantes/metabolismo , Biomarcadores/metabolismo , Femenino , Masculino , Estrés Oxidativo/efectos de los fármacos
3.
Arch Environ Contam Toxicol ; 68(2): 371-81, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25475590

RESUMEN

A large body of evidence was compiled in the recent decades showing a noteworthy increase in the detection of pharmaceutical drugs in aquatic ecosystems. Due to its ubiquitous presence, chemical nature, and practical purpose, this type of contaminant can exert toxic effects in nontarget organisms. Exposure to pharmaceutical drugs can result in adaptive alterations, such as changes in tissues, or in key homeostatic mechanisms, such as antioxidant mechanisms, biochemical/physiological pathways, and cellular damage. These alterations can be monitored to determine the impact of these compounds on exposed aquatic organisms. Among pharmaceutical drugs in the environment, antibiotics are particularly important because they include a variety of substances widely used in medical and veterinary practice, livestock production, and aquaculture. This wide use constitutes a decisive factor contributing for their frequent detection in the aquatic environment. Tetracyclines are the individual antibiotic subclass with the second highest frequency of detection in environmental matrices. The characterization of the potential ecotoxicological effects of tetracycline is a much-required task; to attain this objective, the present study assessed the acute toxic effects of tetracycline in the freshwater fish species Gambusia holbrooki by the determination of histological changes in the gills and liver, changes in antioxidant defense [glutathione S-transferase (GST), catalase (CAT), and lipoperoxidative damage] as well as potential neurotoxicity (acetylcholinesterase activity). The obtained results suggest the existence of a cause-and-effect relationship between the exposure to tetracycline and histological alterations (more specifically in gills) and enzymatic activity (particularly the enzyme CAT in liver and GST in gills) indicating that this compound can exert a pro-oxidative activity.


Asunto(s)
Antibacterianos/toxicidad , Tetraciclina/toxicidad , Contaminantes Químicos del Agua/toxicidad , Animales , Catalasa/metabolismo , Ciprinodontiformes/metabolismo , Agua Dulce/química , Glutatión Transferasa/metabolismo
4.
Osteoporos Int ; 24(3): 1045-55, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22618269

RESUMEN

UNLABELLED: This study provides information on the prevalence of the most important risk factors for osteoporosis and osteoporotic fracture in a large sample of women and men from the Valencia region and also provides the FRAX 10-year major and hip fracture risks for this population, as well as data about the use of diagnostic tests and antiosteoporotic treatments. INTRODUCTION: The purpose of this study was to describe demographic characteristics, osteoporosis risk factors, the 10-year risk of osteoporotic fracture, and the use of densitometry and antiosteoporotic treatments in the Valencia region, Spain. METHODS: A cross-sectional study using the ESOSVAL cohort baseline data was conducted. We analyze the data from 5,310 women and 5,725 men aged 50 and over who attended to 272 collaborating primary care centers in 2009-2010. We collected the demographic, anthropometric, clinical, and pharmacy data from the electronic medical record. RESULTS: The mean age of participants was 64.3 years old for women and 65.6 years old for men. The most frequent fracture risk factors were sedentary life (22.2 %) and previous fracture (15.8 %) in women and low calcium intake (21.4 %) and current smoker (20.9 %) in men. According to FRAX(®), the 10-year risk of presenting a major fracture was 5.5 % for the women and 2.8 % for the men. The 10-year risk for hip fracture was 1.9 and 1.1 % for the women and the men, respectively; 23.8 % of the women and 5.2 % of the men had a densitometry test, 27.7 % of the women and 3.5 % of the men were taking calcium and/or vitamin D supplements, and 28.2 % of the women (22.0 % in the 50-64 age group) and 2.3 % of the men were taking antiosteoporotic drugs. CONCLUSIONS: The prevalence of certain fracture risk factors not included in the FRAX tool (sedentary life, falls, low calcium intake) is high. In young women, their low risks estimated by FRAX contrast with the high figures for densitometry testing and treatment.


Asunto(s)
Conservadores de la Densidad Ósea/uso terapéutico , Fracturas Osteoporóticas/epidemiología , Fracturas Osteoporóticas/etiología , Accidentes por Caídas/estadística & datos numéricos , Anciano , Densidad Ósea/fisiología , Calcio de la Dieta/administración & dosificación , Estudios Transversales , Utilización de Medicamentos/estadística & datos numéricos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Osteoporosis/diagnóstico , Osteoporosis/tratamiento farmacológico , Osteoporosis/epidemiología , Osteoporosis Posmenopáusica/diagnóstico , Osteoporosis Posmenopáusica/tratamiento farmacológico , Osteoporosis Posmenopáusica/epidemiología , Fracturas Osteoporóticas/prevención & control , Prevalencia , Recurrencia , Factores de Riesgo , Conducta Sedentaria , Fumar/efectos adversos , Fumar/epidemiología , España/epidemiología
5.
Eur J Prosthodont Restor Dent ; 21(3): 127-34, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24261105

RESUMEN

The aim of this study was to investigate the current guidelines used for the undergraduate course subject Removable Partial Denture in Portuguese Dental Schools following the Bologna Process. All Dental Schools were sent a questionnaire, divided into the following areas: (I) organization and syllabus; (II) teaching methods; (III) materials and techniques; Answers about organization and syllabus of course subjects showed the most variability; teaching methods were identical regarding principal textbook and live demonstrations of laboratory/clinical procedures; the same techniques and materials are used in all the schools' dental clinics. The majority of Dental Schools present similar guidelines for removable partial dentures.


Asunto(s)
Diseño de Dentadura , Dentadura Parcial Removible , Educación en Odontología , Prostodoncia/educación , Curriculum , Educación en Odontología/métodos , Humanos , Portugal , Facultades de Odontología , Encuestas y Cuestionarios
6.
Environ Sci Pollut Res Int ; 22(1): 667-78, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25096487

RESUMEN

The presence of pharmaceutical drugs in aquatic ecosystems has been widely reported during the past years. Salicylic acid (SA) is mainly used in human medicine as an analgesic and antipyretic drug, being also active in preventing platelet aggregation. To study the ecotoxicological effects potentially elicited by SA in freshwater fish, brown trout individuals (Salmo trutta fario) were chronically exposed (28 days) to this drug, in order to evaluate the enzymatic and histological effects, in both gills and liver. A qualitative and semi-qualitative evaluation of the gills and liver was performed, and also a quantitative evaluation of various lamellar structures. Oxidative stress was quantified trough the determination of glutathione S-transferases (GSTs), glutathione reductase (GRed), total and selenium-dependent glutathione peroxidase (GPx) and Catalase (Cat) activities. Lipid peroxidative damage was also assessed by the quantification of thiobarbituric acid reactive substances (TBARS) in the liver. The here-obtained data showed the occurrence of oxidative stress, reflected by an increased activity of GPx and GRed in the liver; additionally, it was possible to observe non-specific histological changes in gills. The global significance of the entire set of results is discussed, giving emphasis to the ecological relevance of the responses.


Asunto(s)
Branquias/efectos de los fármacos , Hígado/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Ácido Salicílico/toxicidad , Trucha/metabolismo , Animales , Antioxidantes/metabolismo , Biomarcadores/metabolismo , Catalasa/metabolismo , Ecotoxicología , Peces/metabolismo , Branquias/metabolismo , Glutatión Peroxidasa/metabolismo , Glutatión Reductasa/metabolismo , Peroxidación de Lípido/efectos de los fármacos , Hígado/enzimología , Distribución Aleatoria , Sustancias Reactivas al Ácido Tiobarbitúrico , Pruebas de Toxicidad Subaguda
7.
Int J Impot Res ; 16 Suppl 2: S26-39, 2004 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-15496854

RESUMEN

The aim of this Core Document of the Spanish Consensus on Erectile dysfunction (ED) is to offer guidance to the nonspecialist physician in the management of patients with ED. ED is one of the most frequent chronic health problems in men older than 40 y of age and may also act as a sentinel symptom for other important underlying diseases. Its etiology can be classified into organic, psychogenic, or mixed. In most cases, the underlying cause of ED is usually a chronic health problem (such as diabetes, hypertension, atherosclerosis, and so on) or an adverse drug effect. The initial step in the management is to assess erectile function in patients with risk factors for ED. Once ED has been established, a detailed sexual, medical, and social history, including a review of medications used, is the most important aspect of a patient's assessment. Generally, examination should be limited to the cardiovascular, neurological, and urogenital systems. Fasting glucose and blood lipid profile should be performed in every man with ED, and free testosterone levels in men older than 50 y or if hypogonadism is suspected; other diagnostic tests are optional and should be requested on an individualized basis. In many cases, the most likely cause of ED can be identified based on the above information. Therapeutic intervention should be patient-oriented and based on the expectations and wishes of the patient and his partner, who should be included in discussions whenever possible. Basic interventions common to any type of ED include sexual counseling, lifestyle modifications, treatment of associated medical conditions, and switching to alternative drugs with lower risk of ED. In certain cases, an etiologic treatment may be performed (sex therapy, revascularization surgery, and hormonal therapy). Most patients with ED will benefit from symptomatic treatments; first-line therapy may be prescribed by physicians who are not specialists in ED, and includes oral agents such as inhibitors of phosphodiesterase type 5, currently considered the drugs of choice for initial treatment of ED. Intracavernous drugs are the second-line therapy, and surgical treatments, such as implantation of penile prostheses, are reserved for urologists/andrologists who specialize in ED. Referral may be appropriate where indicated by age, clinical findings, or the patient's request.


Asunto(s)
Disfunción Eréctil , Anamnesis , Derivación y Consulta , Disfunción Eréctil/diagnóstico , Disfunción Eréctil/etiología , Disfunción Eréctil/terapia , Humanos , Masculino , Guías de Práctica Clínica como Asunto , Factores de Riesgo
8.
Water Res ; 36(1): 95-104, 2002 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11767743

RESUMEN

This work deals with the treatment of offshore oilfield wastewater from the Campos Basin (Rio de Janeiro State, Brazil). After coarse filtration, this high saline wastewater was microfiltrated through mixed cellulose ester (MCE) membranes, resulting in average removals of COD, TOC, O&G and phenols of 35%, 25%, 92% and 35%, respectively. The permeate effluent was fed into a 1-L air-lift reactor containing polystyrene particles of 2mm diameter, used as support material. This reactor was operated for 210 days, at three hydraulic retention times (HRT): 48, 24 and 12h. Even when operated at the lowest HRT (12 h), removal efficiencies of 65% COD, 80% TOC, 65% phenols and 40% ammonium were attained. The final effluent presented COD and TOC values of 230 and 55 mg/L, respectively. Results obtained by gas chromatography analyses and toxicity tests with Artemia salina showed that a significant improvement in the effluent's quality was achieved after treatment by the combined (microfiltration/biological) process.


Asunto(s)
Petróleo , Eliminación de Residuos Líquidos/métodos , Purificación del Agua/métodos , Animales , Artemia , Biodegradación Ambiental , Cromatografía de Gases , Filtración , Oxígeno/análisis , Tamaño de la Partícula , Cloruro de Sodio , Pruebas de Toxicidad , Agua/química
9.
J Telemed Telecare ; 3 Suppl 1: 79-81, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9218394

RESUMEN

The virtual medical laboratory (VML) was conceived to provide an Internet-accessible resource, offering access for clinicians and scientists to an invaluable data archive at the institute of Laryngology and Otology, London. The Institute is home to the largest collection of temporal bone, laryngeal, skull and sinus sections in Europe. The skull and sinus collections include an extensive section consisting of animal material. These were contributions from zoos around the world. Over the last 50 years, samples have been carefully sectioned and stained by specialized technicians to produce histology slices of most regions of the head and neck. The aim of the project is to create a virtual medical laboratory, which will provide access to archived histological material as well as computerized tomography and magnetic resonance data. Central to this aim is the reconstruction of the internal anatomy of the temporal bone from two-dimensional histology slices, to create three-dimensional views that can be used for anatomical simulation and surgical training in otolaryngology. State-of-the-art three-dimensional reconstruction and rendering technology allows us to develop such a model. Computer-generated simulation could be made available to all hospitals in which otolaryngology is practised, via digital communication networks. We aim to develop core technology in our own specialty that is applicable to other fields of higher education, which have not been exposed to such modern teaching modalities. This has the potential to become an invaluable teaching resource for anatomists, surgeons and other scientists.


Asunto(s)
Redes de Comunicación de Computadores , Educación Médica/métodos , Otolaringología/educación , Telemedicina/métodos , Interfaz Usuario-Computador , Humanos , Reino Unido
10.
Arq Gastroenterol ; 18(1): 25-9, 1981.
Artículo en Portugués | MEDLINE | ID: mdl-7295071

RESUMEN

Description of a case of malacoplakia involving the ascending colon and appendix in a 11-year-old boy with history of severe diarrhea. The lesions were studied by light and electron microscopy. They were composed of proliferation of histiocytes with the typical cytoplasmic inclusions known as Michaelis-Gutmann bodies. The authors comment the pathogenesis of malakoplakia pointing out its rarity in infancy and in the intestine. They also review the literature and stress the importance of the development of malakoplakia in severe enterocolitis.


Asunto(s)
Apéndice/ultraestructura , Colon/ultraestructura , Enfermedades del Colon/patología , Malacoplasia/patología , Niño , Histiocitos/patología , Humanos , Masculino
19.
ISA Trans ; 48(2): 206-12, 2009 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19100982

RESUMEN

This paper considers the implementation of a current control method for switched reluctance motors (SRMs) and presents a novel approach to the accurate on-line modeling of an SRM drive. A simple autotuning technique for the SRM drives using a PWM controller is considered. Furthermore, conventional PI control and Internal Model Control (IMC) are considered to validate this method and present corresponding robust control analysis for the process. The control structures are comparatively analyzed using standard robustness measures for stability and performance. The proposed PWM controller is simulated and a hardware prototype is then implemented using digital signal processor control to evaluate the method using a 12/8, three-phase SRM. The experimental results of the SRM drive model validates the performance of the current loop.


Asunto(s)
Algoritmos , Diseño Asistido por Computadora , Electrónica/instrumentación , Retroalimentación , Modelos Teóricos , Simulación por Computador , Análisis Numérico Asistido por Computador
20.
Eur J Orthod ; 14(6): 457-61, 1992 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-1486931

RESUMEN

The difficulties of localizing landmarks using standardized lateral skull radiographs has been acknowledged. A method is described for producing an objective way of identifying landmarks on the facial profile leading to a useful segmentation and quantitative description of the contours and features of the face. The method uses scale space filtering techniques and curvature analysis, first employed in pattern recognition. The method has been used on two groups: a random sample of twelve-year-old females and a sample of 10 patients with a normal facial morphology who had cephalometric X-rays taken at 5, 9, 13, 16, and 20 years. It demonstrated that the shape of each of the curves is similar in the first group except in the mouth region. The growth study produced meaningful data on the growth of the face.


Asunto(s)
Cefalometría/métodos , Cara/anatomía & histología , Desarrollo Maxilofacial , Adolescente , Adulto , Conversión Analogo-Digital , Niño , Preescolar , Femenino , Humanos , Reproducibilidad de los Resultados
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA