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1.
Tour Manag Perspect ; 44: 101037, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36406104

RESUMO

This paper explores global differences in travel risk perception based on i) attitudes towards travel abroad, and ii) the time required to plan travel. Baseline data from 2019 is compared with data from 2020, the first year of the COVID-19 pandemic. A methodology based on Big Data is developed through the Skyscanner metasearch engine, working with 20,756 million flight searches and 1979 million flight picks worldwide. We conduct an exploratory analysis by region, followed by a cluster analysis of 45 countries. We argue that the findings respond to uncertainty avoidance, with clear differences between Europe, America and Asia-Pacific. This knowledge has marketing implications for tourist destinations in terms of what marketing messages to convey and the best time to introduce marketing campaigns for each country or group of countries, so that the opportunity for reactivation of tourism is maximised.

2.
Tour Manag Perspect ; 41: 100945, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36267150

RESUMO

We study how risk conditions derived from the COVID-19 pandemic may impact on both the desire to travel and intention to visit of tourists and, therefore, on different stages of the destination choice process. We analyse 5134 million flight searches and 379 million flight picks during 2020 for the 17 largest European tourism source markets. An unweighted index number is employed to measure the average variation for searches and picks, for the year 2020, in relation to the reference base period (year 2019). This is done for air travel in general and to Spain specifically. The study then proceeds to conduct an analysis of 17 international travel destinations that are in the evoked sets of the two largest outbound markets in Europe (Germany and UK). We also identify which markets are most favourable to Spain. The research design can inform cost-efficient marketing decisions in a situation of high uncertainty.

3.
ESMO Open ; 7(2): 100463, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35405437

RESUMO

BACKGROUND: The INMUNOSUN trial had the objective of prospectively evaluating the efficacy and safety of sunitinib as a pure second-line treatment in patients with metastatic renal cell carcinoma (mRCC) who have progressed to first-line immune checkpoint inhibitor (ICI)-based therapies. PATIENTS AND METHODS: A multicenter, phase II, single-arm, open-label study was carried out in patients with a histologically confirmed diagnosis of mRCC with a clear-cell component who had progressed to a first-line regimen of ICI-based therapies. All patients received sunitinib 50 mg once daily orally for 4 weeks, followed by a 2-week rest period following package insert instructions. The primary outcome was the objective response rate. RESULTS: Twenty-one assessable patients were included in the efficacy and safety analyses. Four patients [19.0%, 95% confidence interval (CI) 2.3% to 35.8%] showed an objective response (OR), and all of them had partial responses. Additionally, 14 (67%) patients showed a stable response, leading to clinical benefit in 18 patients (85.7%, 95% CI 70.7% to 100%). Among the four assessable patients who showed an OR, the median duration of the response was 7.1 months (interquartile range 4.2-12.0 months). The median progression-free survival (PFS) was 5.6 months (95% CI 3.1-8.0 months). The median overall survival (OS) was 23.5 months (95% CI 6.3-40.7 months). Patients who had better antitumor response to first-line ICI-based treatment showed a longer PFS and OS with sunitinib. The most frequent treatment-emergent adverse events were diarrhea (n = 11, 52%), dysgeusia (n = 8, 38%), palmar-plantar erythrodysesthesia (n = 8, 38%), and hypertension (n = 8, 38%). There was 1 patient who exhibited grade 5 pancytopenia, and 11 patients experienced grade 3 adverse events. Eight (38%) patients had serious adverse events, four of which were considered to be related to sunitinib. CONCLUSION: Although the INMUNOSUN trial did not reach the pre-specified endpoint, it demonstrated that sunitinib is active and can be safely used as a second-line option in patients with mRCC who progress to new standard ICI-based regimens.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Carcinoma de Células Renais/tratamento farmacológico , Carcinoma de Células Renais/secundário , Feminino , Humanos , Indóis/efeitos adversos , Neoplasias Renais/tratamento farmacológico , Neoplasias Renais/patologia , Masculino , Estudos Prospectivos , Sunitinibe/efeitos adversos
5.
Eur J Clin Nutr ; 75(5): 748-753, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33097829

RESUMO

BACKGROUND/OBJECTIVES: Radiotherapy (RT) is a component of therapy for head and neck cancer (HNC) with a negative nutritional impact. Our aim was to compare an early versus a conventional nutritional intervention. SUBJECTS AND METHODS: Retrospective study of HNC patients undergoing RT. Evolution before and after the establishment of a fast-track circuit was evaluated. A conventional group (CG) made up of patients submitted to the nutrition unit during RT after nutritional deterioration, was compared to an early group (EG) represented by patients included in a fast-track circuit, starting nutritional follow-up before the beginning of RT. Only patients with preserved oral intake were involved. Demographic, nutritional and clinical variables were analyzed. Data of hospitalizations and deaths were collected up to three months after RT. RESULTS: 135 subjects constituted the EG and 39 the CG. At baseline, the prevalence of malnutrition was lower in the EG (31.9% vs 69.5%, p = 0.0001), as was the need for nutritional supplements (40% vs 79.5%, p = 0.0001) or nasogastric tube (0% vs 12.8%, p = 0.0001) in comparison to the CG. Three months after RT, there were less patients with oral nutritional support in the EG (79.1% vs 96.9%, p = 0.018), and the number of emergency visits (0.75 vs 1.1 episodes per patient, p = 0.021) and hospitalizations was also lower in this group (29% vs 59%, p = 0.044). CONCLUSIONS: The fast-track approach made early intervention possible. Therefore, patients maintained a better nutritional status, needed less nutritional support and their evolution improved, with a significant decrease in hospitalizations.


Assuntos
Neoplasias de Cabeça e Pescoço , Desnutrição , Neoplasias de Cabeça e Pescoço/complicações , Neoplasias de Cabeça e Pescoço/radioterapia , Humanos , Desnutrição/etiologia , Estado Nutricional , Apoio Nutricional , Estudos Retrospectivos
6.
J Dent ; 88: 103162, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31283963

RESUMO

OBJECTIVES: To evaluate the effectiveness of different endodontic canal sealers for dentin permeability reduction and to determine the viscoelastic performance of root dentin after their application. METHODS: Cervical, medial and apical root dentin surfaces were treated with two experimental hydroxyapatite-based cements, containing sodium hydroxide (calcypatite) or zinc oxide (oxipatite); an epoxy resin- based canal sealer, AH Plus; and gutta-percha. Root dentin was evaluated for fluid filtration. Field emission scanning electron microscopy, energy dispersive analysis, AFM, Young's modulus and Nano-DMA analysis were also performed, at the inner and outer zones of dentin. RESULTS: Dentin treated with oxipatite showed the lowest microleakage among groups with hermetically sealed tubules and zinc-based salt formations. Samples treated with oxipatite showed the highest Ei at the cervical dentin third among groups, at 6 m of storage. Oxipatite promoted the highest complex modulus and tan delta values at the inner zone of both cervical and medial root dentin. Calcypatite favored the lowest tan delta outcomes at the inner zone of apical dentin at 6 m. CONCLUSIONS: Specimens treated with oxipatite showed the highest sealing ability, based on the highest Young's modulus and dentin mineralization, achieved by closing dentinal tubules, voids and pores that reinforced the inner zone of root dentin. The homogeneity of viscoelastic properties among the different root dentin thirds favored the energy dissipation without creating zones of stress concentration and micro-cracking which would have challenge micropermeability. Thereby, among the tested materials oxipatite is proposed as canal filling material and sealer in endodontics. CLINICAL SIGNIFICANCE: Oxipatite could be considered a good candidate for root canal filling material and sealer due to its improved long-term sealing ability and to the advanced remineralization, and so to the enhanced energy dissipation achieved at the inner zone of the radicular dentin.


Assuntos
Dentina , Guta-Percha , Materiais Restauradores do Canal Radicular , Raiz Dentária , Dente não Vital , Óxido de Zinco , Apatitas , Cavidade Pulpar , Resinas Epóxi , Humanos , Hidroxiapatitas , Teste de Materiais
7.
Rev. esp. anestesiol. reanim ; 66(3): 157-162, mar. 2019. ilus, tab
Artigo em Espanhol | IBECS | ID: ibc-187380

RESUMO

En los últimos tiempos la incorporación de la ultrasonografía a las técnicas de anestesia locorregional ha permitido la descripción de diversos bloqueos torácicos fasciales con finalidad analgésica: PECS 1 y 2, bloqueo del plano del serrato, bloqueo fascial intercostal serrato, bloqueo en el plano del músculo transverso torácico..., que se han añadido a otros bloqueos nerviosos ya conocidos como el bloqueo paravertebral torácico o el bloqueo intercostal. En este sentido, las técnicas de anestesia locorregional han sido universalmente recomendadas en pacientes con procesos respiratorios severos para evitar el soporte ventilatorio y posterior destete que incrementan considerablemente las tasas de morbimortalidad postoperatoria. Sin embargo, a nivel de la pared torácica y hueco axilar, son escasas las referencias que identifiquen el uso de bloqueos nerviosos o fasciales como método anestésico principal. Presentamos 2 casos extremos de pacientes pluripatológicos con serio compromiso respiratorio que se someten de forma exitosa a mastectomía radical modificada más cirugía en el hueco axilar mediante una combinación de bloqueos torácicos ecoguiados que permitieron la cirugía sin necesidad de inducir anestesia general, evitando ventilación mecánica, y manteniendo durante todo el procedimiento quirúrgico y postoperatorio respiración espontánea. Describimos las principales indicaciones de los bloqueos anestésicos empleados, incidiendo en la técnica de realización de los mismos y subrayando de forma novedosa la posibilidad de afrontar una cirugía agresiva a nivel de la axila con solo anestesia locorregional


The addition of ultrasound to locoregional anaesthesia in the last few years has led to the description of various fascial thoracic blocks with analgesic purposes: PECS 1 and 2 block, serratus plane block, serratus intercostal fascial block, blockade in the plane of the thoracic transverse muscle..., which have been added to other well-known nerve blocks, such as thoracic paravertebral block or intercostal block. In this sense, locoregional anaesthesia has been universally recommended in patients with severe respiratory processes in order to avoid ventilatory support and subsequent weaning that considerably increases postoperative morbidity and mortality rates. However, as regards thoracic wall and axillary hollow, there are very few references which detail the use of nerve or fascial blocks as a main anaesthetic method. Two extreme cases are presented of multi-pathological patients with serious respiratory disease who successfully underwent a modified radical mastectomy plus surgery in the axillary space using a combination of ultrasound-guided thoracic blocks that allowed surgery without general anaesthesia, avoiding mechanical ventilation, and maintaining spontaneous breathing throughout the surgical procedure. The main indications of the anaesthetic blocks used are described, focusing on the performance of the technique and underlining, in a novel way, the possibility of facing aggressive surgery at the level of the armpit with only locoregional anaesthesia


Assuntos
Humanos , Feminino , Idoso , Bloqueio Nervoso/métodos , Anestesia por Condução/métodos , Mastectomia Radical Modificada/métodos , Insuficiência Respiratória/complicações , Neoplasias da Mama/cirurgia , Nervos Torácicos/efeitos dos fármacos , Nervos Intercostais/efeitos dos fármacos , Excisão de Linfonodo/métodos
8.
Rev Esp Anestesiol Reanim (Engl Ed) ; 66(3): 157-162, 2019 Mar.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-30503529

RESUMO

The addition of ultrasound to locoregional anaesthesia in the last few years has led to the description of various fascial thoracic blocks with analgesic purposes: PECS 1 and 2 block, serratus plane block, serratus intercostal fascial block, blockade in the plane of the thoracic transverse muscle..., which have been added to other well-known nerve blocks, such as thoracic paravertebral block or intercostal block. In this sense, locoregional anaesthesia has been universally recommended in patients with severe respiratory processes in order to avoid ventilatory support and subsequent weaning that considerably increases postoperative morbidity and mortality rates. However, as regards thoracic wall and axillary hollow, there are very few references which detail the use of nerve or fascial blocks as a main anaesthetic method. Two extreme cases are presented of multi-pathological patients with serious respiratory disease who successfully underwent a modified radical mastectomy plus surgery in the axillary space using a combination of ultrasound-guided thoracic blocks that allowed surgery without general anaesthesia, avoiding mechanical ventilation, and maintaining spontaneous breathing throughout the surgical procedure. The main indications of the anaesthetic blocks used are described, focusing on the performance of the technique and underlining, in a novel way, the possibility of facing aggressive surgery at the level of the armpit with only locoregional anaesthesia.


Assuntos
Anestesia/métodos , Neoplasias da Mama/complicações , Neoplasias da Mama/cirurgia , Mastectomia Radical Modificada , Bloqueio Nervoso/métodos , Transtornos Respiratórios/complicações , Idoso , Feminino , Humanos , Índice de Gravidade de Doença
9.
Semergen ; 44(3): 174-179, 2018 Apr.
Artigo em Espanhol | MEDLINE | ID: mdl-28863875

RESUMO

INTRODUCTION: The objective of the present study is to study the prevalence, as well as the clinical and epidemiological characteristics of hypothyroid disease in adults using the computerised clinical records. MATERIAL AND METHODS: Observational, descriptive and cross-sectional study. The target population was the patients of the health centres of Lucena I and II (Córdoba). INCLUSION CRITERIA: Patients 14 years or older, diagnosed with hypothyroidism, born and resident in Lucena. Two hundred and fourteen patients were recruited by random sampling, who then underwent a clinical interview using a questionnaire. RESULTS: The mean age of the patients was 49.71 years (SD 17.03; 95% CI 47.34-51.98), with 85.5% women. A diagnosis of sub-clinical hypothyroidism was found in 74.8%, compared to 18.7% of primary hypothyroidism, and 6.5% of secondary hypothyroidism. The 53.7% (95% CI 46.81-60.59) of patients diagnosed with hypothyroidism did not have thyroid antibodies results. However, 75.2% (95% CI 68.89-80.86) were being treated with levothyroxine. The prevalence of hypothyroidism was 5.7% (95% CI 5.46-5.96). CONCLUSIONS: Sub-clinical hypothyroidism is very common in Primary Care clinics. Many patients are not correctly diagnosed and many are over-medicated, suggesting a need to review the diagnosis.


Assuntos
Autoanticorpos/imunologia , Hipotireoidismo/epidemiologia , Tiroxina/administração & dosagem , Adulto , Estudos Transversais , Feminino , Humanos , Hipotireoidismo/diagnóstico , Hipotireoidismo/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Prevalência , Espanha , Inquéritos e Questionários
10.
Eur J Pharm Sci ; 111: 186-194, 2018 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-28923571

RESUMO

The purpose of this study was to compare the in vivo efficacy of several timolol (TM)-loaded liposomal formulations with current TM antiglaucoma treatment (aqueous 0.5% w/v eye drops). In this study, conventional liposomes (CL) and deformable liposomes, without (DL1) and with ethanol (DL2) were prepared and characterized. In addition, in vitro release and permeation studies, as well as in vivo lowering intraocular pressure (IOP) and biocompatibility studies were performed. It was found that the quali and quantitative lipid bilayer composition played a significant role in modifying the physical properties of vesicles. The deformability study and electronic microscopy images revealed that membrane elasticity of DL1 and DL2 was much higher than CL. However, in vitro permeation results showed that the flux and permeability coefficient were significantly higher in CL compared to DL. The IOP study revealed that TM-loaded CL showed the best pharmacological activity, in comparison to deformable vesicles. Compared to the eye drops, CL formulation could equally reduce the IOP but using a concentration 10-fold lower, whereas the effective time was significantly longer. In addition, the formulations showed no irritant effects after instillation on the ocular surface.


Assuntos
Antagonistas Adrenérgicos beta/administração & dosagem , Lipossomos/química , Nanoestruturas/química , Timolol/administração & dosagem , Administração Oftálmica , Antagonistas Adrenérgicos beta/farmacocinética , Animais , Relação Dose-Resposta a Droga , Etanol/efeitos adversos , Etanol/química , Lipossomos/efeitos adversos , Masculino , Nanoestruturas/efeitos adversos , Soluções Oftálmicas , Coelhos , Tensoativos/efeitos adversos , Tensoativos/química , Timolol/farmacocinética
11.
Cir. mayor ambul ; 22(3): 138-143, jul.-dic. 2017. tab, graf
Artigo em Espanhol | IBECS | ID: ibc-170322

RESUMO

Introducción: En junio de 2014, se produjo el traslado del Hospital Universitario Central de Asturias a un edificio de nueva construcción, pasando de contar con más de 1.200 camas a no llegar a las 1.000. En el contexto de la Cirugía Mayor Ambulatoria (CMA) supuso un gran desafío para todo el personal implicado. La cirugía ambulatoria en el nuevo hospital se gestiona mediante un circuito independiente desde el momento en el que el paciente es clasificado como ambulatorio en la consulta quirúrgica, y solo vuelve al circuito con ingreso si, en la valoración preanestésica, se descarta como paciente ambulatorio. Durante 2015 se ha conseguido la integración de todos los servicios quirúrgicos en la cirugía ambulatoria. Objetivos: Realizar balance del periodo 2014-2016 respecto al incremento de la cirugía ambulatoria en el nuevo contexto, así como exponer y comparar las cifras de los índices de ambulatorización y de sustitución durante estos años. Material y método: Estudio descriptivo, observacional realizado en la Unidad de Cirugía Mayor Ambulatoria durante 2014-2016. Los datos se obtuvieron de nuestra base de datos, sus cifras fueron proporcionadas por el Servicio de Admisiones y Unidad de Control de Gestión. Resultados: A partir del traslado al nuevo hospital, el porcentaje de ambulatorización alcanza el 40 % del total de la cirugía programada. En el año 2016 es del 43,8 %, observándose unos elevados índices en Oftalmología, Cirugía Plástica, ORL y Cirugía Maxilofacial; Urología y Cirugía General muestran evolución ascendente (AU)


Introduction: In June 2014, the Central University Hospital of Asturias was moved to a new building, having more than 1,200 beds initially and not reaching 1,000 laten In the context of Ambulatory Major Surgery (AMS), it was a great challenge to the staff involved. Outpatient surgery in the new hospital is managed through an independent circuit since the patient is classified as an outpatient at the surgery consultation. The patient is included in the hospitalization circuit only, if in the pre-anesthetic evaluation, is not classified as outpatient. During the year 2015, the integration of all surgical services in ambulatory surgery has been achieved. Objectives: To make a balance of the period 2014-2016 regarding the increase of the ambulatory surgery in the new context, as well as to expose and compare the outpatient surgery and substitution rates during these years. Material and methods: Descriptive, observational study performed at the Ambulatory Major Surgery Unit during the period 2014-2016. The data was obtained from our database and its figures were provided by the Admissions Service and the Management Control Unit. Results: With the new hospital the percentage of outpatient surgery reaches 40% of the total of the scheduled surgery. In 2016 it is 43.8%, with high rates in Ophthalmology, Plastic Surgery, Otorhinolaryngology and Maxillofacial Surgery. Urology and General Surgery show ascending evolution (AU)


Assuntos
Humanos , Procedimentos Cirúrgicos Ambulatórios/métodos , Indicadores de Qualidade em Assistência à Saúde/organização & administração , Hospitais Universitários/organização & administração , Anestesia por Condução , Estudos Retrospectivos
12.
Drug Dev Ind Pharm ; 42(10): 1683-94, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26981839

RESUMO

The purpose of this work was to analyze the deformability properties of different timolol maleate (TM)-loaded transfersomes by extrusion. This was performed because elastic liposomes may contribute to the elevation of amount and rate of drug permeation through the corneal membrane. This paper describes the optimization of a transfersome formulation by use of Taguchi orthogonal experimental design and two different statistical analysis approaches were utilized. The amount of cholesterol (F1), the amount of edge-activator (F2), the distribution of the drug into the vesicle (F3), the addition of stearylamine (F4) and the type of edge-activator (F5) were selected as causal factors. The deformability index, the phosphorous recovery, the vesicle size, the polydispersity index, the zeta potential and percentage of drug entrapped were fixed as the dependent variables and these responses were evaluated for each formulation. Two different statistical analysis approaches were applied. The better statistical approach was determined by comparing their prediction errors, where regression analysis provided better optimized responses than marginal means. From the study, an optimized formulation of TM-loaded transfersomes was prepared and obtained for the proposed ophthalmic delivery for the treatment of open angle glaucoma. It was found that the lipid to surfactant ratio and type of surfactant are the main key factors for determining the flexibility of the bilayer of transfersomes. From in vitro permeation studies, we can conclude that TM-loaded transfersomes may enhance the corneal transmittance and improve the bioavailability of conventional TM delivery.


Assuntos
Portadores de Fármacos , Lipossomos/química , Tensoativos/química , Timolol/análise , Administração Cutânea , Disponibilidade Biológica , Sistemas de Liberação de Medicamentos , Tensoativos/administração & dosagem , Timolol/química
13.
J Chromatogr A ; 1429: 53-64, 2016 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-26718187

RESUMO

A novel molecularly imprinted solid phase extraction (MISPE) methodology followed by liquid chromatography tandem mass spectrometry (LC-MS/MS) has been developed using cylindrical shaped molecularly imprinted pills for detection of Δ(9)-tetrahydrocannabinol (THC), 11-nor-Δ(9)-tetrahydrocannabinol carboxylic acid (THC-COOH), cannabinol (CBN) and cannabidiol (CBD) in urine and oral fluid (OF). The composition of the molecular imprinted polymer (MIP) was optimized based on the screening results of a non-imprinted polymer library (NIP-library). Thus, acrylamide as functional monomer and ethylene glycol dimethacrylate as cross-linker were selected for the preparation of the MIP, using catechin as a mimic template. MISPE pills were incubated with 0.5 mL urine or OF sample for adsorption of analytes. For desorption, the pills were transferred to a vial with 2 mL of methanol:acetic acid (4:1) and sonicated for 15 min. The elution solvent was evaporated and reconstituted in methanol:formic acid (0.1%) 50:50 to inject in LC-MS/MS. The developed method was linear over the range from 1 to 500 ng mL(-1) in urine and from 0.75 to 500 ng mL(-1) in OF for all four analytes. Intra- and inter-day imprecision were <15%. Extraction recovery was 50-111%, process efficiency 15.4-54.5% and matrix effect ranged from -78.0 to -6.1%. Finally, the optimized and validated method was applied to 4 urine and 5 OF specimens. This is the first method for the determination of THC, THC-COOH, CBN and CBD in urine and OF using MISPE technology.


Assuntos
Líquidos Corporais/química , Canabinoides/análise , Técnicas de Química Analítica/instrumentação , Técnicas de Química Analítica/métodos , Água , Cromatografia Líquida , Dronabinol/análise , Humanos , Metacrilatos/química , Polímeros/química , Saliva/química , Extração em Fase Sólida , Solventes/química , Espectrometria de Massas em Tandem , Urina/química
14.
Pharm Dev Technol ; 21(7): 823-831, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26135385

RESUMO

The use of lipid nanosystems as drug delivery to the central nervous system may be advantageous over the current strategies. The aim of this study was to develop and characterize functionalized liposomes for treatment of brain diseases. The covalent method of coupling IgG to liposomes via the derivatized lipid 1,2-dioleoyl-sn-glycero-3-phosphoethanolamine-N-[4-(p-maleimidophenyl)butyramide](MPB-PE) was investigated. Optimized coupling conditions are shown to result in the efficient conjugation of IgG to liposomes containing low concentrations of MPB-PE (3/1 SH:IgG). The qualitative analysis has shown that after the extrusion process, more homogeneous populations of vesicles have been obtained with a nanometric size suitable to be effective to further anchor the protein. Negative values of zeta potential demonstrate that they are stable systems. Lyophilization was used to maintain the stability of the formulation. These very interesting results encourage further investigations to formulate peptide- and protein-loaded immunoliposomes, making targeting of liposomes as an attractive approach for brain drug delivery.


Assuntos
Encéfalo/efeitos dos fármacos , Lipídeos/química , Nanopartículas/administração & dosagem , Nanopartículas/química , Encefalopatias/tratamento farmacológico , Química Farmacêutica/métodos , Sistemas de Liberação de Medicamentos/métodos , Imunoglobulina G/química , Lipossomos/administração & dosagem , Lipossomos/química , Tamanho da Partícula , Fosfatidiletanolaminas/química
15.
Talanta ; 135: 58-66, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25640126

RESUMO

A water compatible molecularly imprinted polymer (MIP), synthesized using theophylline (TPH) as dummy-template and acrylamide (AM) as functional monomer, has been employed as supporting material in matrix solid-phase dispersion combined with ultra performance liquid chromatography-photodiode array detection (MSPD-UPLC-PDA) for selective determination of adenosine triphosphate (ATP) derivatives in fish samples. ATP degradation products are used as freshness index for assessment of fish quality. The solid sample was directly blended with MIP in MSPD procedure resulting in sample disruption and subsequent adsorption of the compounds on the MIP. By using n-hexane and ammonium hydroxide aqueous solution at pH 9 as the washing and elution solvent, respectively, satisfactory recoveries and clean chromatograms have been obtained. Good linearity for hypoxanthine (HYP) and inosine (INO) has been observed with correlation coefficients (R(2)) of 0.9987 and 0.9986, respectively. The recoveries of the two ATP derivatives at three different spiked levels ranged from 106.5% to 113.4% for HYP and from 103.1% to 111.2% for INO, with average relative standard deviations lower than 4.2% in both cases. This new method, which is rapid, simple and sensitive, can be used as an alternative tool to conventional tedious methods.


Assuntos
Trifosfato de Adenosina/química , Qualidade dos Alimentos , Gadiformes , Hipoxantina/análise , Inosina/análise , Animais , Análise de Alimentos , Impressão Molecular
16.
Anal Bioanal Chem ; 406(15): 3589-97, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24429976

RESUMO

The use of molecularly imprinted polymers (MIPs) for solid phase extraction (MISPE) allows a rapid and selective extraction compared with traditional methods. Determination of Δ(9)-tetrahydrocannabinol (THC) and 11-nor-Δ(9)-tetrahydrocannabinol carboxylic acid (THC-COOH) in oral fluid (OF) and urine was performed using homemade MISPEs for sample clean-up and liquid chromatography tandem mass spectrometry (LC-MS/MS). Cylindrical MISPE shaped pills were synthesized using catechin as a mimic template. MISPEs were added to 0.5 mL OF or urine sample and sonicated 30 min for adsorption of analytes. For desorption, the MISPE was transfered to a clean tube, and sonicated for 15 min with 2 mL acetone:acetonitrile (3:1, v/v). The elution solvent was evaporated and reconstituted in mobile phase. Chromatographic separation was performed using a SunFire C18 (2.5 µm; 2.1 × 20 mm) column, and formic acid 0.1% and acetonitrile as mobile phase, with a total run time of 5 min. The method was fully validated including selectivity (no endogenous or exogenous interferences), linearity (1-500 ng/mL in OF, and 2.5-500 ng/mL in urine), limit of detection (0.75 and 1 ng/mL in OF and urine, respectively), imprecision (%CV <12.3%), accuracy (98.2-107.0% of target), extraction recovery (15.9-53.5%), process efficiency (10.1-46.2%), and matrix effect (<-55%). Analytes were stable for 72 h in the autosampler. Dilution 1:10 was assured in OF, and Quantisal™ matrix effect showed ion suppression (<-80.4%). The method was applied to the analysis of 20 OF and 11 urine specimens. This is the first method for determination of THC and THC-COOH in OF using MISPE technology.


Assuntos
Cromatografia Líquida , Dronabinol/análogos & derivados , Dronabinol/análise , Dronabinol/urina , Polímeros/química , Espectrometria de Massas em Tandem , Acetona/química , Acetonitrilas/química , Líquidos Corporais , Calibragem , Toxicologia Forense/métodos , Humanos , Hidrólise , Controle de Qualidade , Reprodutibilidade dos Testes , Extração em Fase Sólida , Solventes/química , Detecção do Abuso de Substâncias/métodos , Urinálise
17.
Int Endod J ; 47(3): 246-56, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23772839

RESUMO

AIM: To compare the accuracy of working length (WL) determination using the Raypex 6(®) electronic apex locator and cone-beam computed tomography (CBCT). METHODOLOGY: A total of 150 extracted human teeth were decoronated and randomly assigned to five groups (n = 30). WL was measured with the Raypex 6(®) at both the 'constriction' and the 'apex' marks under dry conditions (group 1) or with 2.5% NaOCl, distilled water or Ultracain(®) (groups 2-4). The radiological WL (group 5) was calculated from bucco-lingual and mesio-distal CBCT sections. Differences between electronic, CBCT measurements and actual length (AL) were calculated. Positive and negative values, respectively, indicate measurements falling short or long of AL. Two-way anova and the Bonferroni and Welch tests were used to compare mean differences amongst groups. The chi-squared and Fisher's exact tests were used to compare percentages of precise, ±0.5 and ±1.0 mm of the AL measurements amongst the experimental groups. Statistical analysis was performed at α = 0.05. RESULTS: Mean differences with respect to AL ranged from 0.26 to -0.36 mm and from 0.05 to 0.18 mm, respectively, for the electronic measurements at the 'constriction' mark and 'apex' mark. CBCT measurements were an average of 0.59 mm shorter than AL. Percentages of electronic measurements falling within ±0.5 mm of the corresponding AL referred to the 'apex' mark were greater than at the 'constriction' mark, but the differences were only significant in group 4 (with Ultracain(®) ). Percentages of CBCT measurements falling within ±0.5 mm of AL (46.7%) were significantly lower than electronic measurements, regardless of the condition of the root canal. In 30-38.5% of the measurements taken at the 'apex' mark and in 3.4-13.3% of those at the 'constriction' mark, the file tip extended beyond the foramen. CONCLUSIONS: Electronic measurements were more reliable than CBCT scans for WL determination. The Raypex 6(®) was more accurate in locating the major foramen than the apical constriction under the experimental set-up.


Assuntos
Tomografia Computadorizada de Feixe Cônico , Eletrônica Médica , Odontometria/instrumentação , Ápice Dentário/anatomia & histologia , Cavidade Pulpar/anatomia & histologia , Cavidade Pulpar/diagnóstico por imagem , Humanos , Processamento de Imagem Assistida por Computador , Técnicas In Vitro , Ápice Dentário/diagnóstico por imagem
18.
ACS Appl Mater Interfaces ; 5(8): 3281-9, 2013 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-23537090

RESUMO

In this paper, investigations were carried out on catechin-loaded maleic anhydride (MAH)-modified polypropylenes (PP). Two maleic-modified polypropylenes (PPMAH) with different maleic concentrations have been blended with PP and catechin to obtain composites of improved catechin retention with the aim of studying the possible interactions between these grafted polymers with antioxidants, and a secondary interest in developing an active antioxidant packaging. Composite physicochemical properties were measured by thermal analysis (thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), and oxidation induction time (OIT)) and infrared spectroscopy studies. Catechin release profiles into food simulants were obtained by HPLC-PDA-QqQ, following European legislation. Antiradical activity of composites was analyzed by the ABTS and DPPH method. The formation of intermolecular hydrogen bonds between catechin and functionalized PP has been confirmed by Fourier transform infrared (FTIR) studies. Besides, a small fraction of ester bonds, formed as a result of a chemical reaction between a fraction of the hydrolyzed anhydride and the catechin hydroxyl groups, is not discarded. OIT results also showed an increase in antioxidant effectiveness caused by the presence of catechin- and maleic-modified PPMAH in the blend formulations. Incorporation of MAH-grafted PP increased substantially the retention rate of catechin, being dependent on the MAH content of the grafted polypropylene. The described interactions between catechin and maleic groups, together with changes in PP morphology in comparison with reference PP explained lower antioxidant release. Besides formulation, antioxidant release was dependent on the type of food, the temperature, and the time.


Assuntos
Catequina/química , Embalagem de Alimentos/instrumentação , Anidridos Maleicos/química , Polímeros/química , Polipropilenos/química , Cinética
19.
Colloids Surf B Biointerfaces ; 105: 14-23, 2013 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-23352939

RESUMO

In this paper, two techniques, differential scanning calorimetry (DSC) and phosphorus nuclear magnetic resonance ((31)P-NMR), have been used to characterize sumatriptan succinate-loaded charged liposomes. To complete the results obtained by DSC a hot stage microscopy (HSM) technique was used. Data concerning the drug entrapment efficiency were published in a previous paper. The differences in data concerning encapsulation into negatively and positively-charged vesicles, indicated an influence of drug in the structural conformation of lipids in the bilayer. Moreover, the inability to formulate chargeless vesicles contributed to the opinion that a physical formulation study might be relevant. Phosphatidylcholine and cholesterol were used as lipid film forming agents, whereas stearylamine (positive) and dicetylphosphate (negative) were added as charge-inducing agents. DSC studies demonstrated that phosphatidylcholine caused the disappearance of the melting peak (Tm) of sumatriptan succinate because a drug dissolution process occurs. In addition, thermograms showed interesting interactions between stearylamine and dicetylphosphate with sumatriptan succinate favoring drug entrapment into the liposomes. In the present work, (31)P-NMR technique demonstrated that the structural conformation of lipids in the membrane affected drug encapsulation into multilamellar (MLVs) and unilamellar (LUVs) vesicles. Bilayer structure in a liquid crystalline phase of the positively-charged REV liposomes membrane has demonstrated a high structural stability and a better encapsulation efficacy for sumatriptan succinate than negatively-charged TLE and REV liposomes. Therefore, phosphatidylcholine interaction with sumatriptan succinate appears to be the cause of the inability to obtain neutral sumatriptan succinate liposomes.


Assuntos
Varredura Diferencial de Calorimetria , Colesterol/química , Bicamadas Lipídicas/metabolismo , Lipossomos/química , Espectroscopia de Ressonância Magnética , Fosfatidilcolinas/química , Sumatriptana/química , Aminas/farmacologia , Colesterol/metabolismo , Organofosfatos/farmacologia , Fosfatidilcolinas/metabolismo , Sumatriptana/metabolismo
20.
Acta pediatr. esp ; 71(1): 21-27, ene. 2013. ilus
Artigo em Espanhol | IBECS | ID: ibc-109400

RESUMO

El objetivo de las publicaciones secundarias es informar a los clínicos acerca de los avances más importantes alcanzados en medicina, cuyos resultados tengan la máxima probabilidad de ser verdaderos y útiles. Para ello, se seleccionan artículos publicados en revistas médicas primarias y se presentan en un formato de resumen estructurado, seguido de un comentario crítico realizado por expertos en la materia. Las revistas secundarias de interés en Pediatría son AAP GrandRounds, The PedsCCM Evidence-Based Journal, la sección «Current Best Evidence» de Journal of Pediatrics, la sección «Archimedes» de Archives of Disease in Childhood, y la sección «Atención Primaria Basada en la Evidencia» de Formación Médica Continuada, Revista Evidencia Actualización en la Práctica Ambulatoria y Evidencias en Pediatría. Analizamos con cierto detalle Evidencias en Pediatría, una revista secundaria pediátrica y en español, órgano oficial de la Asociación Española de Pediatría (AEP), y también avalada por la Asociación Latinoamericana de Pediatría (ALAPE)(AU)


The purpose of secondary publications is to alert clinicians to important advances in medicine whose results are most likely to be both true and useful. For this goal, they select from the biomedical literature the original and review artcles that are summarised in abstracts and commented by clinical experts. The most important secondary publications in pediatrics are AAP GrandRounds, PedsCCM Evidencie-Based Journal, the section of «Current Best Evidence» from the Journal of Pediatrics, the section of «Archimedes» from Archives Disease in Childhood, the section of «Atención Primaria Basada en la Evidencia» from Formación Médica Continuada, Revista Evidencia Actualización en la Práctica Ambulatoria y Evidencias en Pediatría. We review in detail Evidencias en Pediatría, a seconday publication in spanish from the Asociación Española de Pediatría (Spanish Association of Pediatrics) (AEP) and endorsed by the Asociación Latinoamericana de Pediatría (Latin American Association of Pediatrics) (ALAPE)(AU)


Assuntos
Humanos , Masculino , Feminino , Criança , Adolescente , Serviços de Informação/organização & administração , Serviços de Informação/estatística & dados numéricos , Serviços de Informação/normas , Medicina Baseada em Evidências/métodos , Medicina Baseada em Evidências/tendências , Publicações Periódicas como Assunto/estatística & dados numéricos , Publicações Periódicas como Assunto/normas , Publicações Periódicas como Assunto , Bibliometria , Sistemas de Informação/normas , Sistemas de Informação , Uso da Informação Científica na Tomada de Decisões em Saúde
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