RESUMO
In anatomic pathology, the current state encompassing the pre-analytic processes of tissue collection, handling, examination, preparation, processing, and storage are largely uncontrolled, inconsistently performed, and/or not standardized according to the sound scientific data. Pre-analytic defects result in nearly three-quarters of the problems in laboratory diagnostics. This is evident in quality surveys from well-respected institutions that document high miss rates in the required basics of information related to patient and tissue identity, let alone parameters documenting quality aspects related to the surgical specimen and its preservation. This talk will describe the historical approach to tissue processing and identify gaps from worldwide observations in current laboratory practices. It will also offer potential methodological and technological solutions and process improvements that laboratories may consider in serving the ultimate users of pathology information: the clinician and the patient. It illustrates the need for scientifically validated specimen guidelines and a performance based, standardized and documented "chain of custody" of the pre-analytical steps from the patient's body through fixation. For thought leaders and professional standard setters, opportunities for optimizing molecular studies exist in specimen collection, transfer, grossing, fixation, and decalcification protocols. In this evolving era of molecular profiling and personalized therapeutic decision-making, a well-reasoned and coordinated focus on pre-analytic processes that optimizes specimens for subsequent testing will result in: Improved specimen quality for molecular testing Improved accuracy of diagnostic and molecular test results Reduced Turnaroundtimes for same-day diagnosis Enhanced satisfaction of clinicians and patients.
Assuntos
Serviços de Laboratório Clínico/tendências , Padrões de Prática Médica/tendências , Manejo de Espécimes , Serviços de Laboratório Clínico/normas , Técnica de Descalcificação/instrumentação , Técnica de Descalcificação/métodos , Humanos , Laboratórios/tendências , Microtomia/instrumentação , Microtomia/normas , Microtomia/tendências , Padrões de Prática Médica/normas , Manejo de Espécimes/instrumentação , Manejo de Espécimes/normas , Manejo de Espécimes/tendências , Preservação de Tecido/instrumentação , Preservação de Tecido/normas , Preservação de Tecido/tendências , Coleta de Tecidos e Órgãos/instrumentação , Coleta de Tecidos e Órgãos/normas , Coleta de Tecidos e Órgãos/tendências , Meios de Transporte/instrumentação , Meios de Transporte/normas , VácuoRESUMO
With the introduction of new biological agents for cancer treatment enabling 'personalized medicine', treatment decisions based on the molecular features of the tumour are more common. Consequently, tissue evaluation in tumour pathology is becoming increasingly based on a combination of classical morphological and molecular analysis. The results of diagnostic tests rely not only on the quality of the method used but, to a large extent, also on the quality of specimens, which is dependent on the pre-analytical procedures and storage. With the introduction of predictive immunohistochemical and molecular tests in clinical pathology, improvement and standardization of pre-analytical procedures has become crucial. The aim of this review is to increase awareness with regard to tissue handling and for standardization of the pre-analytical phase of a diagnostic process. In addition, several processing steps in tissue handling that need to be improved in order to obtain the quality needed for modern molecular medicine will be discussed. Optimal, standardized procedures are crucial if a high standard of test results is to be achieved, which is what each patient deserves.
Assuntos
Neoplasias/diagnóstico , Patologia Clínica/tendências , Medicina de Precisão/tendências , Técnicas Histológicas/normas , Técnicas Histológicas/tendências , Humanos , Patologia Clínica/normas , Fixação de Tecidos , Preservação de TecidoRESUMO
A new process design and operation for the extraction of essential oils was developed. Microwave hydrodiffusion and gravity (MHG) is a combination of microwaves for hydrodiffusion of essential oils from the inside to the exterior of biological material and earth gravity to collect and separate. MHG is performed at atmospheric pressure without adding any solvent or water. MHG has been compared with a conventional technique, hydrodistillation (HD), for the extraction of essential oil from two aromatic herbs: spearmint (Mentha spicata L.) and pennyroyal (Mentha pulegium L.) belonging to the Labiatae family. The essential oils extracted by MHG for 15 min were quantitatively (yield) and qualitatively (aromatic profile) similar to those obtained by conventional hydrodistillation for 90 min. MHG also prevents pollution through potential 90% of energy saved which can lead to greenhouse gas emission benefits.
Assuntos
Gravitação , Micro-Ondas , Óleos Voláteis/isolamento & purificação , Cromatografia Gasosa , Difusão , Mentha/química , Óleos Voláteis/químicaRESUMO
An improved process of Soxhlet extraction assisted by microwave, called microwave-integrated Soxhlet (MIS) is proposed for the extraction of oils and fats from different food matrixes such as oleaginous seeds, meat and bakery products. Optimal conditions for extraction were obtained using a response surface methodology and reached from a central composite design allowing us to conclude in a previous paper that the proposed process ensures complete, efficient and accurate extraction for lipids determination from olives. In this paper, the peak areas of the main fatty acids extracted with MIS from olive seeds were considered as response variables and submitted to an analysis of variance in order to determine if there was a significant link between the extraction of fatty acids and the variables required in extraction procedures. Results have shown that MIS parameters do not affect the composition of the extracts. For the generalization of the study with several food matrixes, MIS extraction results obtained were then compared to conventional Soxhlet extraction in terms of crude extract and fatty acid composition and shown that the oils extracted by MIS were quantitatively and qualitatively similar to those obtained by conventional Soxhlet extraction. MIS labstation can be considered as a new and general alternative for the extraction of lipids by using microwave energy.
Assuntos
Fracionamento Químico/métodos , Gorduras na Dieta/análise , Micro-Ondas , Óleos/análise , Fracionamento Químico/instrumentação , Análise de Alimentos/instrumentação , Análise de Alimentos/métodos , Reprodutibilidade dos TestesRESUMO
Here is described a green and original alternative procedure for fats and oils' determination in oleaginous seeds. Extractions were carried out using a by-product of the citrus industry as extraction solvent, namely d-limonene, instead of hazardous petroleum solvents such as n-hexane. The described method is achieved in two steps using microwave energy: at first, extractions are attained using microwave-integrated Soxhlet, followed by the elimination of the solvent from the medium using a microwave Clevenger distillation in the second step. Oils extracted from olive seeds were compared with both conventional Soxhlet and microwave-integrated Soxhlet extraction procedures performed with n-hexane in terms of qualitative and quantitative determination. No significant difference was obtained between each extract allowing us to conclude that the proposed method is effective and valuable.
Assuntos
Fracionamento Químico/métodos , Cicloexenos/química , Micro-Ondas , Óleos de Plantas/análise , Terpenos/química , Fracionamento Químico/instrumentação , Limoneno , Estrutura Molecular , Azeite de Oliva , Óleos de Plantas/química , Reprodutibilidade dos Testes , SolventesRESUMO
A new process of Soxhlet extraction assisted by microwave was designed and developed. The process is performed in four steps, which ensures complete, rapid and accurate extraction of the samples. A second-order central composite design (CCD) has been used to investigate the performance of the new device. The results provided by analysis of variance and Pareto chart, indicated that the extraction time was the most important factor followed by the leaching time. The response surface methodology allowed us to determine optimal conditions for olive oil extraction: 13 min of extraction time, 17 min of leaching time, and 720 W of irradiation power. The proposed process is suitable for lipids determination from food. Microwave-integrated Soxhlet (MIS) extraction has been compared with a conventional technique, Soxhlet extraction, for the extraction of oil from olives (Aglandau, Vaucluse, France). The oils extracted by MIS for 32 min were quantitatively (yield) and qualitatively (fatty acid composition) similar to those obtained by conventional Soxhlet extraction for 8 h. MIS is a green technology and appears as a good alternative for the extraction of fat and oils from food products.
Assuntos
Técnicas de Química Analítica/métodos , Micro-Ondas , Olea/química , Óleos de Plantas/isolamento & purificação , Análise de Variância , Técnicas de Química Analítica/economia , Ecologia , Segurança de Equipamentos , Ácidos Graxos/análise , Azeite de Oliva , Temperatura , Fatores de TempoRESUMO
Without adding any solvent or water, we proposed a novel and green approach for the extraction of secondary metabolites from dried plant materials. This "solvent, water and vapor free" approach based on a simple principle involves the application of microwave irradiation and earth gravity to extract the essential oil from dried caraway seeds. Microwave dry-diffusion and gravity (MDG) has been compared with a conventional technique, hydrodistillation (HD), for the extraction of essential oil from dried caraway seeds. Essential oils isolated by MDG were quantitatively (yield) and qualitatively (aromatic profile) similar to those obtained by HD, but MDG was better than HD in terms of rapidity (45min versus 300min), energy saving, and cleanliness. The present apparatus permits fast and efficient extraction, reduces waste, avoids water and solvent consumption, and allows substantial energy savings.
Assuntos
Carum/química , Química Verde/métodos , Óleos Voláteis/isolamento & purificação , Óleos de Plantas/isolamento & purificação , Especiarias/análise , Difusão , Gravitação , Química Verde/instrumentação , Micro-Ondas , Óleos Voláteis/análise , Óleos de Plantas/análise , Sementes/químicaRESUMO
Development of new procedures in analytical chemistry is currently increasingly focussed on reducing the time, cost and energy to carry out routine analyses. The conventional Dean-Stark (CDS) distillation to determine the water content is one of the most commonly used analytical methods and uses large amounts of solvent and energy. A new microwave accelerated Dean-Stark (MADS) distillation is presented as an alternative procedure. Microwaves were applied to a mixture of toluene, Weflon stir bar and olives, and the corresponding water was collected in a Dean-Stark receiver. This procedure permits fast and efficient determination of the water content of olives. Reliability and reproducibility were evaluated using statistical analyses. Different matrices were then used with MADS and the results were compared to CDS. Water determination from olives with MADS was better than that with CDS in terms of energy saving, rapidity (10 min versus 120 min), reproducibility, and cleanliness.
Assuntos
Micro-Ondas , Água/análise , Custos e Análise de Custo , Química Verde , Cinética , Reprodutibilidade dos Testes , Segurança , Fatores de TempoRESUMO
Traditional hydrodistillation (HD), supercritical fluid extraction (SFE), organic solvent extraction (SE), and water microwave assisted hydrodistillation (MAHD) techniques were compared and evaluated for their effectiveness in the isolation of rosemary essential oil. The microwave assisted hydrodistillation technique was optimized in terms of both delivered power and time duration. The extracts/distillates were analyzed by GC and GC-MS. Microwave distillation, which exploits the physical action of microwaves on plants, showed a series of advantages over the other approaches: low cost, use of water in sample pre-treatment step, greatly reduced isolation time, and attainment of high quality essential oil distillate. Moreover, the absence of environmental impact of this innovative technique was also emphasized.