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Sample records for etileno pet pos-consumo

  1. Preparation of polymer blends from glycerol, fumaric acid and of poly(ethylene terephthalate) (PET) recycled; Preparacao de blendas polimericas a partir do glicerol, acido fumarico e do politereftalato de etileno (PET) pos consumo

    Energy Technology Data Exchange (ETDEWEB)

    Medeiros, Marina A.O.; Guimaraes, Danilo H.; Brioude, Michel M.; Jose, Nadia M. [Instituto de Quimica, Universidade Federal da Bahia, Salvador, BA (Brazil); Prado, Luis A.S. de A. [Institut fuer Kunststoffe und Verbundwerkstoffe - Technische Universitaet Hamburg-Harburg, Hamburg (Germany)

    2011-07-01

    Polymer blends based on recycled poly(ethylene terephthalate) (PET) and poly(glycerol fumarate) polyesters were prepared in different PET concentrations. The PET powder was dispersed during the poly(glycerol fumarate) synthesis at 260 deg C. The resulting blends were characterized by X-ray diffraction. The thermal stability of the materials was evaluated by thermogravimetric analysis and differential scanning calorimetry. The morphology was studies by scanning electron microscopy. The blends were clearly immiscible. The possibility of (interfacial) compatibilization of the PET domains, caused by transesterification reactions between PET and glycerol were discussed. (author)

  2. Study of poly(ethylene terephthalate) - PET post consumption and its properties, when it is undergone ionizing radiation; Estudo da reciclagem do poli(tereftalato de etileno) (PET) pos-consumo e de suas propriedades, quando submetido a radiacao ionizante

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Antonio Claudio dos

    2008-07-01

    The plastic materials have an important role in the life style changing, in the lives of the people and it is more and more utilized in the production and consumption by the world population. By the plastic utilization, it became possible the growth phenomenon of disposable products. As a consequence of this conjecture, the recycling of these materials becomes an obliging option of the modern society. The economy provided by the reutilization of the recycling materials is advantageous not only in consideration to the reutilization of the natural resources involved in these products, but specially for its benefit provided in which concern to the preservation of the environmental matters. Within the big universe of the plastics and plastic packaging materials, available in the current market, it was carried out, during this work, the mechanical recycling of the packagings post consumption, produced from PET polymer and more specifically, the bottles used in packagings for beverages as a whole; such as carbonated beverages, mineral water, isotonic, and so on. Thus, the aim of this work was to recycle the PET post-consumption and evaluate the effects provoked by the action of different ionizing radiation doses, in the properties of this recycled polymer, based on virgin PET. Based on the conclusive results, it was taken for granted that the effects provoked by the action of the ionizing radiation from the electron beam by electron accelerators and gamma rays emitted by {sup 60}Co source in the virgin and recycled PET polymer promoted the predominance of the scission reactions at random of the main chain, with consequent decrease of the polymer molecular weight. Such fact was corroborated by the flow index essay and intrinsic viscosity. It was also carried out, thermal analysis by Differential Scanning Calorimetry (DSC) proving the decreasing of molecular weight in the irradiated PET samples. (author)

  3. Process of chemical recycling of post-consumer PET using a factorial design; Processo de reciclagem quimica do PET pos-consumo empregando o planejamento fatorial

    Energy Technology Data Exchange (ETDEWEB)

    Lacerda, Carlos Eduardo de O.; Almeida, Yeda Medeiros B. de; Vinhas, Gloria M., E-mail: carlos.olacerda@hotmail.com [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil)

    2015-07-01

    The present study investigated important variables in the depolymerization reaction of post-consumer poly (ethylene terephthalate) - PET via alkaline hydrolysis. Through this reaction is obtained terephthalic acid (PTA), a monomer, which when purified, is used for the production of PET resin. The study was based on a 2{sup 2} factorial design in which the independent variables were the concentration of NaOH solution and the reaction time, and the dependent variable was the yield of PTA obtained. The experiments that generated the best results, 100 % of yield, were obtained with the higher values of the independent variables. Statistical analysis showed that the concentration of NaOH solution is the variable that most influences in the process. The PTA obtained was analyzed by NMR ¹H technique, confirming the strong resemblance to commercial PTA obtained by petrochemical way. (author)

  4. Polymeric blends from post-consumer PET and polyester becoming of glycerol and phthalic acid; Misturas polimericas a partir do PET pos-consumo e poliesteres derivados do gliceraol e acido ftalico

    Energy Technology Data Exchange (ETDEWEB)

    Miranda, C.S.; Brioude, M.; Fiuza, R.P.; Luporini, S.; Carvalho, R.F.; Jose, N.M., E-mail: cleidienesm@gmail.co [Universidade Federal da Bahia (GECIM/UFBA), Salvador, BA (Brazil). Inst. de Quimica. Grupo de Energia e Ciencias dos Materiais

    2010-07-01

    Preparation of physical mixture or polymer blends is a very important method to obtain a final product with excellent balance of properties, where one component can compensate for the poor property of another, and is often a modified low cost compared to development and synthesis of a new polymer. PET has become a major waste of post-consumer plastics and aiming to remedy this problem, this work aims to obtain blends from recycled PET and polyesters derived from glycerol and phthalic acid. The material with higher proportion of PET showed better thermal properties, observed by TGA and DSC, with a similar profile of pure PET. In XRD analysis showed a semicrystalline, while the SEM is a smooth surface on all materials, characteristic of pure polyester. The ratio of 50% its surface showed a probable immiscibility of polymers. (author)

  5. Chemical recycling of post-consumer PET: structural characterization of terephthalic acid and the effect of Alkaline Hydrolysis at low temperature; Reciclagem quimica do PET pos-consumo: caracterizacao estrutural do acido tereftalico e efeito da hidrolise alcalina em baixa temperatura

    Energy Technology Data Exchange (ETDEWEB)

    Fonseca, Talitha Granja; Almeida, Yeda Medeiros Bastos de; Vinhas, Gloria Maria, E-mail: gmvinhas@yahoo.com.br [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Dept. de Engenharia Quimica

    2014-09-15

    Due to the environmental impact caused by PET packaging disposal, this material recycling has been thoroughly discussed and evaluated. In particular, chemical recycling enables achievement of the monomers that are used in PET resin manufacture: ethylene glycol (EG) and terephthalic acid (PTA). Therefore, studies for this process optimization are important from environmental and economic points of view. The present study investigated certain parameters that influence the depolymerization reaction of PET post-consumer via alkaline hydrolysis in order to obtain PTA. Assays were performed at 70 °C by varying the concentration of sodium hydroxide and the reaction time. The best results were obtained at 10.82 mol L{sup -1} NaOH and 9 h reaction time. Consequently, it was possible to prove this process viability, once analyses by infrared and nuclear magnetic resonance confirmed that PTA was obtained in all reactions performed. (author)

  6. Despolimerização do poli (tereftalato de etileno - PET: efeitos de tensoativos e excesso de solução alcalina Depolymerization of waste polyethylene terephthalate - PET: effects of surfactants and excess of alkaline solutions

    Directory of Open Access Journals (Sweden)

    Luiz Di Souza

    2008-01-01

    Full Text Available A despolimerização do poli (tereftalato de etileno - PET pós-consumo, em solução aquosa 7,5 mol.L-1 de hidróxido de sódio foi testado a 100 °C e a 1 atm, com objetivo de obter o ácido tereftálico. O efeito de tensoativos e da concentração da solução sobre o rendimento da despolimerização foi estudado quantitativamente via gravimetria e analises térmica. Excesso de solução alcalina aumenta a velocidade de reação dobrando o rendimento em reações com partículas grosseiras. Os tensoativos DDS e Tween são eficientes na catálise das reações equimolares com partículas grosseiras, mas não afetam as reações com solução alcalina em excesso.The depolymerization of waste polyethylene terephthalate (PET in aqueous solutions 7.5 M of sodium hydroxide was tested at 100 °C and 1 atm, in order to obtain the terephthalic acid monomers (TPA. The effect from surfactants and concentration of sodium hydroxide (NaOH on the reaction extent of depolymerization was studied quantitatively by gravimetric and thermal measurements. Excess of alkaline solution catalyze the reaction and doubled the reaction rate with larger particle size PET. The surfactants DDS and Tween are efficient in catalyzing larger particle size PET under equimolar conditions, but do not affect the reactions under excess of alkaline solution.

  7. Reciclagem de rejeitos de poli(tereftalato de etileno (PET e de poliamida (PA por meio de extrusão reativa para a preparação de blendas Recycling of wastes from poly(ethylene tereftalate (PET and polyamide (PA by reactive extrusion for preparation of polymeric blends

    Directory of Open Access Journals (Sweden)

    Caio T Ferreira

    2011-01-01

    Full Text Available O consumo crescente de materiais poliméricos em diversas formas de aplicação leva à produção de uma quantidade enorme de resíduos pós-consumo e pós-industriais com potencial poluidor elevado. A reciclagem mecânica é uma das maneiras mais adequadas para contornar os problemas gerados por estes rejeitos, uma vez que permite conciliar interesse econômico com benefícios ambientais. Neste trabalho foi feito um estudo sobre a reciclagem de rejeitos pós-industriais de poli(tereftalato de etileno (PET provenientes da fabricação de mantas de tecido não tecido e de resíduos de poliamida (PA oriundos de pneus usados na forma de blendas, produzidas por meio de extrusão reativa dos dois resíduos em presença de catalisador. Os resultados obtidos a partir de caracterização térmica e química das blendas evidenciaram a ocorrência de trans-reações entre segmentos de cadeia polimérica dos dois polímeros, possibilitando a compatibilização do sistema. A produção de blendas PET/PA se configura como uma forma adequada para a reciclagem dos rejeitos de PET e de PA.The increasing use of polymeric materials in several applications leads to the production of a high amount of post consume and post industrial wastes with expressive pollutant potential. Mechanical recycling is an important way to decrease the problems caused by these wastes because it allows one to associate economic viability with environmental benefits. In this paper a study was carried out on the recycling of poly(ethylene tereftalate (PET wastes from the production of nonwoven fabrics (NWF and of polyamide (PA wastes from old tires for production of polymeric blends via reactive extrusion in the presence of trans-reaction catalysts. The results from thermal and chemical characterization indicated trans-reactions between segments of polymeric chains of the two polymers, promoting the system compatibilization. The production of PET/PA blends is an interesting alternative

  8. Poli(tereftalato de etileno, PET: uma revisão sobre os processos de síntese, mecanismos de degradação e sua reciclagem Poly(ethylene terephthalate, PET: a review on the synthesis processes, degradation mechanisms and its recycling

    Directory of Open Access Journals (Sweden)

    Wanderson Romão

    2009-06-01

    Full Text Available Apresentamos uma revisão sobre o poli(tereftalato de etileno enfatizando os processos de síntese e os mecanismos de degradação. Atualmente o Brasil apresenta um dos maiores índices mundiais de reciclagem mecânica deste polímero, correspondendo a um percentual de 53%. O sucesso desse termoplástico na indústria de reciclagem deve-se à sua ampla diversidade de aplicações, desde a indústria têxtil (multifilamento até as indústrias de alimentos, onde as embalagens recicladas grau alimentício poderão ser misturadas com a resina virgem em diversas proporções e reprocessadas para o uso. Uma abordagem sobre a atual legislação do uso de PET reciclado em contato com alimentos também é mostrada neste trabalho. No processo de síntese do PET realizado em duas ou três etapas, são usados comonômeros e aditivos para otimizar as condições de processamento do material. Entretanto, tanto durante a síntese como no processo de reciclagem, ocorrem reações de degradação (termomecânica e termo-oxidativa e reações secundárias, formando acetaldeído, oligômeros, e o dietileno glicol. A presença desses "contaminantes" acelera o processo de degradação do polímero, afetando a qualidade do produto final.We present a review on poly(ethylene terephthalate, emphasizing the synthesis processes and the degradation mechanisms. Brazil is currently among the countries that most recycle PET, with 53% of this polymer being mechanically recycled. The success of this thermoplastic in the recycling industry is due to its large diversity of applications, from the textile industry to food packaging, where the food grade recycled packages will be mixed with the pristine resin for reprocessing and use. We also discuss the present legal aspects concerning PET recycling and its use in contact with food. In the synthesis of PET, usually done in two or three steps, several co-monomers and additives are used to optimize the final properties and

  9. Atrito e desgaste de recobrimentos de PET, politeraftalato de etileno, pós-consumo processados por aspersão térmica Friction and wear of a thermal sprayed PET - poly(ethylene teraphthalate coating

    Directory of Open Access Journals (Sweden)

    Rogério A. X. Nunes

    2007-09-01

    Full Text Available A aspersão térmica envolve processos de recobrimentos que podem utilizar materiais cerâmicos, poliméricos, metálicos ou misturas destes. O material a ser depositado é fundido total ou parcialmente. As partículas aquecidas são aceleradas e projetadas em direção a uma superfície devidamente preparada, onde se formam camadas com estrutura lamelar. Os efeitos das variáveis do processo de aspersão, pressão dos gases de combustão, taxa de alimentação e gás de arraste no transporte do material, sobre a resistência ao desgaste e atrito de filmes PET foram investigados. Os recobrimentos de PET foram caracterizados através do desgaste micro-abrasivo, utilizando o ensaio de caloteste, e da medida dos coeficientes de atrito, com o ensaio de pino-sobre-disco. Os valores do coeficiente de desgaste abrasivo e do coeficiente de atrito dos recobrimentos são comparados com os valores da garrafa PET utilizada como referência. Os coeficientes de desgaste encontrados foram similares aos valores de garrafas PET da ordem de 10-5. As análises estatísticas dos resultados deste trabalho indicam que os efeitos das interações das três variáveis, pressão dos gases de combustão, taxa de alimentação e gás de arraste foram significativos para o coeficiente de desgaste e não significativos para o coeficiente de atrito.The thermal spray technique involves coating processes that can use ceramic, polymers, metallic materials or a blend of these. The material to be deposited is melted totally or partially, where the heated particles are accelerated and projected toward a prepared surface forming layers with a lamellar structure. The effect of the spray process parameters such as, combustion pressure, feed rate and carrier gas, on the wear resistance and friction of PET films was evaluated. The PET coatings were characterized by measuring the wear coefficient through the calowear type testing and the friction coefficients using pin-on-disk testing

  10. Sensibilidade da rosa 'Osiana' ao etileno

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    Delaine Cristina Cordeiro

    2011-01-01

    Full Text Available Os objetivos deste trabalho foram determinar a sensibilidade e as respostas da rosa cultivar Osiana (Rosa × hybrida à presença de etileno ao longo da vida pós-colheita. Para determinar a sensibilidade da flor ao etileno, hastes foram cortadas e colocadas em câmaras herméticas e em seguida tratadas por 24 horas com diferentes concentrações de etileno variando de 0,0; 0,1; 1,0; 10; 100 e 1000 µL L-1do ar no interior da câmara. A rosa teve a vida pós-colheita reduzida pelo etileno, quando exposta a concentração igual ou superior a 10 µL L-1 de etileno. As flores tratadas com no mínimo de 10 µL L-1de etileno desenvolveram necrose, murcha e abscisão prematura das pétalas ainda túrgidas. As concentrações de 0,1 e 1,0 µL L-1de etileno estimularam a abertura do botão floral durante o período de 24 horas de exposição ao etileno, sem no entanto, reduzir a vida pós-colheita. A rosa 'Osiana' pode ser classificada como uma cultivar sensível ao etileno e a concentração influência os processos estimulados.

  11. Síntese e Caracterização de Nanocompósitos de Poli(3-hidroxibutirato) - PHB/ZnO e Poli(tereftalato de etileno) - PET/ZnO

    OpenAIRE

    Lima Júnior, Reginaldo Gomes de

    2015-01-01

    Neste trabalho o óxido de zinco nanoestruturado (ZnOnano) foi incorporado em duas matrizes poliméricas: o poli(hidroxibutirato), e o poli(tereftalato de etileno), com o objetivo de avaliar o efeito desta adição nas propriedades físicas, químicas, bem como a atividade antimicrobiana para o nanocompósito PHB/ZnOnano, tendo como referência a bactéria Escherichia coli. Filmes de PHB/ZnOnano foram produzidos por casting, com parâmetros de síntese obtidos a partir de um planejamento experimental 24...

  12. Recobrimentos de poli (tereftalato de etileno depositados em aço por aspersão térmica a partir de pós obtidos em diferentes condições de moagem Thermally sprayed coated carbon steel produced using PET powder obtained in different grinding conditions

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    Luciana Tavares Duarte

    2003-07-01

    Full Text Available Neste trabalho foram analisados recobrimentos de poli(tereftalato de etileno, PET, depositados em aço carbono através da técnica de aspersão térmica à combustão, e produzidos a partir de pós oriundos de processos de moagem, em moinho de bolas e de facas, de garrafas de PET pós-consumo. Algumas condições de moagem foram testadas, tendo-se obtido pós com diferentes características morfológicas. As características morfológicas dos pós e dos recobrimentos foram avaliadas por microscopia óptica e eletrônica, tendo-se observado que o recobrimento apresentava bolhas, provavelmente devido à degradação do polímero. Além disto, os recobrimentos produzidos, bem como as amostras de pó, foram caracterizados por espectroscopia na região do infravermelho, por calorimetria exploratória diferencial e através da determinação de viscosidade intrínseca em solução. Os resultados obtidos mostraram que é possível a produção de aço carbono recoberto com PET através da técnica de aspersão térmica, sendo que o grau de degradação, a morfologia e a distribuição granulométrica dos pós utilizados influenciaram significativamente as características e propriedades dos recobrimentos formados.The main purpose of this work was to study the production of a thermal spray coated poly(ethyleneterephthalate steel. Poly(ethylene terephthalate coatings were made of a thin grinding waste produced by a PET recycling company, and of a PET powder, which was obtained by grinding post-consumer beverage bottles. Some grinding conditions, using a ceramic ball mill, were studied. Scanning Electronic Microscopy (SEM and optical microscopy (OM were used in the study of powder and coating morphologies, and this analysis showed that PET coating presents bubbles due to polymer degradation. PET powder and coating characteristics were investigated using Differential Scanning Calorimetry (DSC and measurements of intrinsic viscosity. It was observed that

  13. Sensibilidade da rosa 'Osiana' ao etileno

    OpenAIRE

    Delaine Cristina Cordeiro; Fernando Luiz Finger; Joice Simone dos Santos; Juliane Karsten; José Geraldo Barbosa

    2011-01-01

    Os objetivos deste trabalho foram determinar a sensibilidade e as respostas da rosa cultivar Osiana (Rosa × hybrida) à presença de etileno ao longo da vida pós-colheita. Para determinar a sensibilidade da flor ao etileno, hastes foram cortadas e colocadas em câmaras herméticas e em seguida tratadas por 24 horas com diferentes concentrações de etileno variando de 0,0; 0,1; 1,0; 10; 100 e 1000 µL L-1do ar no interior da câmara. A rosa teve a vida pós-colheita reduzida pelo etileno, quando expos...

  14. Study of the radiosterilization dose effect on properties of poly(ethylene terephthalate) - PET recycled; Estudo do efeito da dose de radioesterilizacao sobre as propriedades do poli(tereftalato de etileno) - PET reciclado

    Energy Technology Data Exchange (ETDEWEB)

    Isoldi, Ana Beatriz Godoy; Silva, Leonardo Gondim de Andrade e [Instituto de Pesquisas Energeticas e Nucleares (IPEN), Sao Paulo, SP (Brazil); Rosario, Salmo Cordeiro do [Plasticos Muller S.A. Industria e Comercio, Sao Paulo, SP (Brazil)

    2002-07-01

    The packing are in constant development, in function, especially, the process of globalization. The opening of the brazilian market after currency stabilization, caused technological innovations, change of habits and costumes of the population and environmental matters. Year after year, because of cost reductions, it became more extreme the hard study of the polymeric materials and their copolymers, their possible blends and their recycling, always seeking a better wrapping of the products, especially when it concerns to the food, increasing its shelf life. The process of sterilization of foods and modification of polymers through radiation are targets of growing interest by of the current industries linked to the nutrition and packing sectors. The objective of this paper is to discuss the application of the radiation (electron beam) in the sterilization of packings of recycled poly(ethylene terephthalate) PET, evaluating the possible effects on their properties. (author)

  15. Toxicidad por óxido de etileno

    OpenAIRE

    Téllez M. Jairo A.

    1993-01-01

    El óxido de etileno, es un compuesto epóxido gaseoso, ampliamente utilizado en nuestro medio como agente esterilizante y de desinfección en instituciones hospitalarias. Los estudios realizados en varios países han demostrado efectos sobre la salud humana, caracterizados por  hipersensibilidad dérmica, irritación del tracto respiratorio, irritación ocular, excitación del S.N.C. y se asocia con presencia de abortos expontáneos, aberraciones cromosómicas e irritación crónica de laringe ...

  16. PET

    DEFF Research Database (Denmark)

    Mariager, Rasmus Mølgaard; Schmidt, Regin; Heiberg, Morten Rievers

    PET handler om den hemmelige tjenestes arbejde under den kolde krig 1945-1989. Her fortæller Regin Schmidt, Rasmus Mariager og Morten Heiberg om de mest dramatiske og interessante sager fra PET's arkiv. PET er på flere måder en udemokratisk institution, der er sat til at vogte over demokratiet....... Dens virksomhed er skjult for offentligheden, den overvåger borgernes aktiviteter, og den registrerer følsomme personoplysninger. Historien om PET rejser spørgsmålet om, hvad man skal gøre, når befolkningen i et demokrati er kritisk indstillet over for overvågningen af lovlige politiske aktiviteter......, mens myndighederne mener, at det er nødvendigt for at beskytte demokratiet. PET er på en gang en fortælling om konkrete aktioner og begivenheder i PET's arbejde og et stykke Danmarkshistorie. Det handler om overvågning, spioner, politisk ekstremisme og international terrorisme.  ...

  17. Toxicidad por óxido de etileno

    Directory of Open Access Journals (Sweden)

    Téllez M. Jairo A.

    1993-08-01

    Full Text Available

    El óxido de etileno, es un compuesto epóxido gaseoso, ampliamente utilizado en nuestro medio como agente esterilizante y de desinfección en instituciones hospitalarias. Los estudios realizados en varios países han demostrado efectos sobre la salud humana, caracterizados por  hipersensibilidad dérmica, irritación del tracto respiratorio, irritación ocular, excitación del S.N.C. y se asocia con presencia de abortos expontáneos, aberraciones cromosómicas e irritación crónica de laringe y tráquea en personal expuesto ocupacionalmente.

  18. Quantificação de antimônio em garrafas de politereftalato de etileno (PET) brasileiras por fluorescência de raios-X e avaliação quimiométrica para verificar a presença de pet reciclado através do teor de ferro

    National Research Council Canada - National Science Library

    Gustavo G. Shimamoto; Bianca Kazitoris; Luis F. R. de Lima; Nathassia D. de Abreu; Vitor T. Salvador; Maria Izabel M. S. Bueno; Eustáquio V. R. de Castro; Elói A. S. Filho; Wanderson Romão

    2011-01-01

    .... The literature reports mentions of toxicity associated to antimony. In this work, a green, fast and direct method to quantify antimony, sulfur, iron and copper, in PET bottles by X-ray fluorescence spectrometry is presented...

  19. Quantificação de antimônio em garrafas de politereftalato de etileno (PET brasileiras por fluorescência de raios-X e avaliação quimiométrica para verificar a presença de pet reciclado através do teor de ferro

    Directory of Open Access Journals (Sweden)

    Gustavo G. Shimamoto

    2011-01-01

    Full Text Available Antimony is a common catalyst in the synthesis of polyethylene terephthalate used for food-grade bottles manufacturing. However, antimony residues in final products are transferred to juices, soft drinks or water. The literature reports mentions of toxicity associated to antimony. In this work, a green, fast and direct method to quantify antimony, sulfur, iron and copper, in PET bottles by X-ray fluorescence spectrometry is presented. 2.4 to 11 mg Sb kg-1 were found in 20 samples analyzed. The coupling of the multielemental technique to chemometric treatment provided also the possibility to classify PET samples between bottle-grade PET/recycled PET blends by Fe content.

  20. Resistencia mecanica, tasa respiratoria y produccion de etileno de caqui 'Fuyu' durante el almacenamiento

    National Research Council Canada - National Science Library

    Dussan-Sarria, Saul; Honorio, Sylvio L; de L. Matias, Melissa

    2008-01-01

    .... En este trabajo fue evaluada la alteracion de la resistencia mecanica a la compresion del caqui 'Fuyu', el comportamiento respiratorio y la evolucion de la produccion de etileno durante el almacenamiento...

  1. Caracterização físico-química da superfície de filmes de poli(tereftalato de etileno

    Directory of Open Access Journals (Sweden)

    Pinto Georgia V. V. V.

    1999-01-01

    Full Text Available Dentre as diversas técnicas de caracterização superficial de filmes poliméricos, foram utilizadas nos filmes de PET do presente estudo a refratometria, rugosidade, análises de coeficiente de atrito e ângulo de contato. As amostras de filmes de PET analisadas têm 12mim de espessura e compreendem três tipos de estuturas superficiais: filme de homopolímero PET, filme PET com tratamento corona e filme de poli(tereftalato de etileno-co-ciclohexanodimetanol. O filme com tratamento corona apresentou o maior valor de tensão superficial em função da maior parcela dos grupos polares. Resultados de índice de refração indicam que a superfície do filme com copoliéster é menos cristalina que as superfícies dos demais filmes avaliados. A estruturas amorfa e elevado nível de tensão superficial de filmes tratados deverão favorecer a um aumento dos níveis de adesão a tintas e revestimentos.

  2. Mangas minimamente processadas amadurecidas naturalmente ou com etileno e armazenadas em diferentes embalagens Fresh cut mangos ripped naturaly or induced by ethylene and stored in different packges

    Directory of Open Access Journals (Sweden)

    Bianca Sarzi de Souza

    2006-08-01

    Full Text Available Avaliaram-se produtos minimamente processados de mangas 'Tommy Atkins' amadurecidas naturalmente ou com etileno. Os frutos amadurecidos com aplicação de etileno foram colhidos no estádio "meio-maturo" (de vez e tratados com etileno (1g.L-1 e mantidos em câmaras, por 12 horas, a 23-25ºC e 85-90% UR. Os frutos foram selecionados, lavados com detergente, sanitizados (200mg.L-1 de cloro e armazenados por 12 horas, a 10ºC. Após este período, foram processados sob condições assépticas, a 12ºC, acondicionados em embalagem PET ou bandeja de poliestireno expandido recoberta por filme de PVC e armazenados a 3ºC. Foram avaliados, a cada 3 dias, a resistência e a coloração da polpa, os teores de ácido ascórbico, sólidos solúveis (SS, acidez titulável (AT, carboidratos solúveis, redutores e amido, relação SS/AT, pH e atividade da peroxidase. Durante o período de armazenamento, os pedaços de manga tornaram-se mais firmes e mantiveram-se amarelos, porém mais escurecidos, o que foi indicado por redução na luminosidade. Os teores de ácido ascórbico nos pedaços das mangas amadurecidas com etileno apresentaram-se menores que os das amadurecidas naturalmente. A acidez apresentou tendência de redução durante o armazenamento, com as amadurecidas com etileno apresentando os maiores valores e os menores pH. Os produtos de mangas amadurecidas com etileno apresentaram os maiores valores de SS, mas menor relação SS/AT, indicando gosto mais azedo. Os teores de carboidratos solúveis e de amido não apresentaram variação com tendência definida, mas os de carboidratos redutores apresentaram tendência de acréscimo, e a atividade da peroxidase, de decréscimo durante o armazenamento. Os produtos de mangas amadurecidas naturalmente foram superiores aos amadurecidos com etileno, mantendo boa qualidade e aparência adequada para a comercialização até o 13º dia, enquanto os das amadurecidas com etileno, por 11 dias.Fresh cut 'Tommy

  3. Poli(Etileno Naftalato - PEN: uma revisão do seu histórico e as principais tendências de sua aplicação mundial Poly(ethylene naphtalate - PEN: historical review and main trends in world application

    Directory of Open Access Journals (Sweden)

    Edilene de Cássia D. Nunes

    1998-06-01

    Full Text Available Este artigo contém uma revisão sobre o Poli(etileno naftalato - PEN e também inclui vários aspectos relacionados com as blendas poliméricas Poli(etileno tereftalato - PET / Poli(etileno naftalato - PEN. O artigo é resultado de um desenvolvimento conjunto da Alcoa Alumínio S.A.- Divisão de Embalagens e do Departamento de Engenharia de Materiais - Universidade Federal de São Carlos (UFSCar, que tem como objetivo pesquisar o tema aqui abordado.This paper presents a review on poly(ethylene naphtalate - PEN including several features related to poly(ethylene terephtalate - PET / poly(ethylene naphtalate - PEN blends.The paper is a result of a conjoint development of Alcoa S.A. - Packaging Divisions and of the Department of Materials Engineering - Federal University of São Carlos (UFSCar, whose scope is to investigate the subject here approached.

  4. Efeito compatibilizante de copolímeros contendo segmentos líquido-cristalinos em misturas com poli(tereftalato de etileno) e um poliéster líquido-cristalino termotrópico (TLCP).

    OpenAIRE

    Kátia M. Novack; Stellet,Carla A.; Ailton S. Gomes

    1999-01-01

    Uma série de copolímeros com segmentos líquido-cristalinos foram sintetizados por policondensação em solução a alta temperatura e misturados com poli(tereftalato de etileno) (PET) e um poliéster líquido-cristalino termotrópico (TLCP), previamente sintetizado. Os copolímeros foram utilizados com sucesso como compatibilizantes nas misturas PET/TLCP. As técnicas de caloria diferencial de varredura, análises dinâmico-mecânicas, análises térmicas e microscopia eletrônica (SEM) foram utilizadas na ...

  5. Riscos na reutilização de produtos médicos esterilizados em óxido de etileno

    OpenAIRE

    Sundin, Mônica Saladini

    2014-01-01

    O presente estudo analisou 275 resultados de resíduos de óxido de etileno (OE) e subprodutos tais como etilenoglicol (ETG) e etilenocloridrina (ETCH), em produtos médicos esterilizados com óxido de etileno. A metodologia utilizada difere de outros estudos por não ser uma simulação, mas sim casos reais de produtos esterilizados nos quais se mediu a quantidade de resíduos. As quantidades de resíduos obtidas foram comparadas com os limites máximos estabelecidos por normas. Observou-se uma grande...

  6. Mercado para produtos reciclados à base de PET/HDPE/Ionômero

    Directory of Open Access Journals (Sweden)

    Pacheco Elen B.

    1999-01-01

    Full Text Available A expansão do mercado de poli(tereftalato de etileno (PET, considerada um fenômeno mundial, está acontecendo no Brasil. Hoje, o principal mercado para o PET é o de bebidas carbonatadas. O uso de PET em lugar do vidro vem trazendo inúmeras vantagens, incluindo menor peso, maior resistência ao impacto e menores custos de transporte. Foram estudados possíveis mercados para a mistura PET/HDPE, na proporção de 75/25, acrescida de uma pequena quantidade de compatibilizante. Os resultados do estudo indicam que possíveis mercados para o mistura poderá incluir o de embalagens para usos especiais e partes de automóvel.

  7. Modelamiento de un reactor de lecho fluidizado para la copolimerización de etileno - propileno

    OpenAIRE

    Cadavid Estrada, Juan Guillermo; Conde Cotes, Alfonso

    2010-01-01

    En este artículo se presenta el modelo matemático para un reactor de lecho fluidizadom, en el cual se desarrolla la copolimerización entre etileno y propileno utilizando catalizadores Ziegler - Natta. El modelo incluye el planteamiento de la cinética de la copolimerización, considerando la existencia de dos tipos de sitios activos: reacciones de transferencia espontánea de actividad y reacciones de desactivación. También se estudia y se simula el crecimiento de una partícula polimérica expues...

  8. Atmosfera modificada e controle de etileno para bananas 'Prata-Anã' cultivadas na Amazônia Setentrional Brasileira

    Directory of Open Access Journals (Sweden)

    Marcos André de Souza Prill

    2012-12-01

    Full Text Available O presente trabalho teve por objetivo avaliar o efeito da atmosfera modificada (AM pelo uso de embalagem plástica de polietileno de baixa densidade (PEBD, do vácuo e da adsorção de etileno, visando à manutenção da qualidade das bananas 'Prata-Anã' produzidas em Roraima. As análises foram realizadas em intervalos de 5 dias após a colheita, até 35 dias de armazenamento refrigerado (AR. Verificou-se que os frutos submetidos a embalagem de PEBD apresentaram as menores perdas de massa fresca quando comparados aos demais. Da mesma forma, os frutos embalados na presença do adsorvedor de etileno obtiveram a melhor manutenção na coloração da casca, atraso temporal, do pico climatérico, assim como o retardamento na degradação do amido, os menores incrementos de sólidos solúveis e acidez titulável, as menores concentrações de etileno nos interiores das embalagens e atraso temporal e a diminuição da atividade enzimática. Isso, possivelmente, proporcionou os maiores teores de pectina total e solúvel ao final do período experimental. A combinação do uso da embalagem de PEBD com o sachê de permanganato de potássio (KMnO4 resultou no retardamento do processo de maturação dos frutos de banana 'Prata-Anã', quando armazenada a 12 ºC. Pode-se atribuir esse efeito benéfico à presença do sachê na adsorção de etileno e, consequentemente, na ação do etileno no amadurecimento dos frutos, retardando a senescência das bananas 'Prata-Anã'.

  9. Sistema de gestión de seguridad industrial en una planta de etileno

    OpenAIRE

    Ozores Arriola, Juan

    2017-01-01

    La realización de este Trabajo de Fin de Grado tiene como objetivo la implantación de un Sistema de Gestión de la Seguridad para una planta química de producción de etileno. Para ello, el sistema debe cumplir con todo lo establecido en el estándar OHSAS 18001:2007. El estándar de OHSAS 18001:2007 es el documento de referencia en el que se detallan los requisitos que debe cumplir un sistema de gestión de seguridad y salud en el trabajo. El objetivo principal de este documento es que las org...

  10. Manejo do etileno em ameixas 'Laetitia' armazenadas sob atmosferas controlada e modificada ativa

    Directory of Open Access Journals (Sweden)

    Thais Roseli Corrêa

    2011-09-01

    Full Text Available O objetivo deste trabalho foi avaliar o efeito de condições de atmosfera controlada (AC e atmosfera modificada (AM ativa (filme PEBD de 40 µm, com duas perfurações de 1,0 mm de diâmetro, associadas ao manejo do etileno, sobre a manutenção da qualidade em ameixas 'Laetitia'. Os tratamentos avaliados consistiram no armazenamento refrigerado (60 dias a 0,5±0,1ºC em: atmosfera refrigerada (AR; 21,0 kPa O2 + <0,03 kPa CO2; AM; AM + baixo etileno (BE; AC; e AC + 1-MCP (1,0 µL L-1. As pressões parciais de O2 + CO2 (kPa foram de 1,0 + 1,0 e 2,5 + <0,1, em AC e AM, respectivamente. Os frutos armazenados em AC, independentemente do tratamento com 1-MCP, apresentaram retardo no amadurecimento, quando comparados aos frutos em AR. Contudo, os melhores resultados para a manutenção da textura da polpa e da acidez titulável foram obtidos em AC + 1-MCP. Os tratamentos não interferiram para a incidência de podridões, rachaduras e degenerescência da fruta. Frutos dos tratamentos AM + BE e AC + 1-MCP apresentaram menor escurecimento da polpa e maior aceitabilidade quanto à cor e ao sabor na análise sensorial em relação àqueles armazenados em AR.

  11. Pet Health

    Science.gov (United States)

    Pets can add fun, companionship and a feeling of safety to your life. Before getting a pet, think carefully about which animal is best for ... is each family member looking for in a pet? Who will take care of it? Does anyone ...

  12. Aspectos toxicológicos de la exposición al óxido de etileno

    OpenAIRE

    Prat Marín, Andrés; Sanz Gallén,Pedro

    1987-01-01

    En este trabajo se revisan los principales riesgos de la utilización del óxido de etileno como agente esterilizante del material médico-quirúrgico. Resaltando los efectos tóxicos, mutagénicos, teratogénicos y cancerígenos como los más importantes, enfatizando en la necesidad de adoptar medidas de prevención para controlar dichos riesgos.

  13. Senior Pets

    Science.gov (United States)

    ... of 7 human years for each year in dog years. Age is not a disease. Although senior pets may develop age-related problems, ... develop diseases such as heart, kidney and liver disease, cancer or ... of pets over 10 years of age. Dogs get cancer at roughly the same rate as ...

  14. Armazenamento refrigerado de limões 'Siciliano' tratados com etileno Cold storage of 'Siciliano' lemon treated with ethylene

    Directory of Open Access Journals (Sweden)

    Angelo Pedro Jacomino

    2003-04-01

    Full Text Available O objetivo deste experimento foi avaliar o efeito do tratamento com etileno na conservação refrigerada de limão 'Siciliano'. As frutas foram tratadas com 0; 3; 6 e 12 µL.L-1 de etileno durante 2; 4 ou 6 dias a 20oC. Após os tratamentos, os frutos foram armazenados a 10oC e 90% UR durante 35 dias, e avaliados após 21; 28 e 35 dias. O desverdecimento das frutas ocorreu mais rapidamente à medida que a concentração de etileno e o tempo dos tratamentos foram aumentados. Entretanto, tratamento por 6 dias na concentração de 12µL.L-1 causou podridão nas frutas após 35 dias de armazenamento refrigerado. Não houve efeitos dos tratamentos sobre o teor de sólidos solúveis totais, acidez total titulável, perda de matéria fresca e porcentagem de suco. O tratamento mais recomendado é a aplicação de 6µL.L-1 de etileno durante 4 dias.The objective of this experiment was to evaluate the effect of ethylene treatments upon cold storage of 'Siciliano' lemons. Fruit were treated with 0, 3, 6 or 12µL.L-1 of ethylene during 2,4 or 6 days at 20oC. After treatments, fruit were cold stored at 10oC and 90% RH during 35 days, and evaluated after 21, 28 and 35 days of storage. The degreening was more fasten so far as the ethylene concentration and duration of treatment were increased. However, treatment for 6 days and ethylene concentration of 12µL.L-1 caused decay in fruits after 35 days of cold storage. There was no effect of treatments in the soluble solids content, acidity total titratable, weight loss and juice percentage. Ethylene at 6µL.L-1 during 4 days is the recommendation to degreening of this cultivar.

  15. Citotoxicidade de tubos de PVC esterilizados em óxido de etileno após exposição à radiação gama

    National Research Council Canada - National Science Library

    Rafael Queiroz de Souza; Kazuko Uchikawa Graziano; Tamiko Ichikawa Ikeda; Cláudia Regina Gonçalves; Áurea Silveira Cruz

    2013-01-01

    Materiais esterilizados em raios gama, ao serem re-esterilizados em óxido de etileno (EO), formam substâncias tóxicas? Esta questão norteou o objetivo deste estudo, que foi investigar o potencial efeito...

  16. Diabetic Pets

    Science.gov (United States)

    ... health or management, contact your veterinarian. In addition, diabetic pets should be monitored for long-term complications such as cataracts, which commonly develop in diabetic dogs and cats. Other problems that can occur ...

  17. Giardia & Pets

    Science.gov (United States)

    ... and disinfect my home after my dog or cat is diagnosed with Giardia infection? Clean and disinfect potentially contaminated items (toys, water bowls and food bowls, pet bedding, floors, dog crates, linens, towels, ...

  18. Efeito compatibilizante de copolímeros contendo segmentos líquido-cristalinos em misturas com poli(tereftalato de etileno e um poliéster líquido-cristalino termotrópico (TLCP Compatibilizing effect of copolymers with liquid crystalline segments in blends of poly(ethylene terephthalate and a thermotropic liquid crystalline polyester (TLCP

    Directory of Open Access Journals (Sweden)

    Kátia M. Novack

    1999-12-01

    Full Text Available Uma série de copolímeros com segmentos líquido-cristalinos foram sintetizados por policondensação em solução a alta temperatura e misturados com poli(tereftalato de etileno (PET e um poliéster líquido-cristalino termotrópico (TLCP, previamente sintetizado. Os copolímeros foram utilizados com sucesso como compatibilizantes nas misturas PET/TLCP. As técnicas de caloria diferencial de varredura, análises dinâmico-mecânicas, análises térmicas e microscopia eletrônica (SEM foram utilizadas na caracterização dos polímeros. Foi verificada boa processabilidade e diminuição da velocidade de cristalização das misturas. As micrografias das superfícies fraturadas das amostras, obtidas das análises de SEM, mostraram melhor miscibilidade para as misturas com maior teor de copolímero.A serie of copolyesters with liquid crystalline segments were synthesized by high temperature solution polycondensation and mixed with poly(ethylene terephthalate (PET and a thermotropic liquid crystalline polyester (TLCP, previously synthesized. The copolyesters were successfully applied to compatibilize PET/TLCP blends. The techniques applied to characterize compatibilization were thermal analysis, differential scanning calorimetry, dynamic mechanical analysis and eletron microscopy (SEM. Good processing and depression of crystallization rate were obtained in blends. The SEM micrographs for fractured surface show better miscibility from PET/TLCP blends with higher content of copolymer.

  19. Resposta da maçã cv. Fuji ao etileno no armazenamento em atmosfera controlada Response of Fuji apples to ethylene in controlled atmosphere storage

    Directory of Open Access Journals (Sweden)

    Auri Brackmann

    2001-12-01

    Full Text Available Conduziu-se um experimento com o objetivo de avaliar o efeito das concentrações de etileno sobre a manutenção da qualidade e ocorrência de distúrbios fisiológicos na maçã cv. Fuji armazenada em atmosfera controlada (AC com 1kPa de O2 e 0,2kPa de CO2 na temperatura de 0,5ºC. O delineamento experimental foi o inteiramente casualizado com três repetições. Os tratamentos avaliados foram: 0,25; 20; e, 800m.L-1 de etileno. As avaliações foram realizadas após nove meses de armazenamento, no momento da abertura das câmaras e após sete dias de exposição a 25ºC. Somente os frutos mantidos em 800m.L-1 de etileno durante o período de conservação em AC foram influenciados pelo etileno, apresentando maior respiração e síntese de etileno, menor firmeza de polpa e cor de fundo da epiderme mais amarela do que aqueles armazenados com 0,25 ou 20m.L-1 de etileno na atmosfera da câmara. A maçã 'Fuji' apresentou baixa sensibilidade a altas concentrações de etileno durante o armazenamento em AC, não se justificando a sua absorção em câmaras comerciais.The experiment was carried out aiming to evaluate the effect of ethylene concentrations on the quality and occurrence of physiological disorders on Fuji apples stored in controlled atmosphere (CA with 1kPa O2 / 0,2kPa CO2 at 0.5ºC. The treatments applied were: 0.25; 20; and 800m.L-1 ethylene. The evaluations were accomplished after nine months of storage, at the opening of the chambers and after seven days in shelf life (25ºC. Only the fruits kept at 800m.L-1 ethylene during storage period were influenced by the ethylene, showing higher respiration and ethylene biosynthesis, lower firmness and more yellow background color of the peel than those stored with 0.25 or 20m.L-1. Fuji apples presented low sensibility to high ethylene concentrations during storage in AC, therefore absorption is not recomended in commercial storage rooms.

  20. Positron Emission Tomography (PET)

    Energy Technology Data Exchange (ETDEWEB)

    Welch, M.J.

    1990-01-01

    Positron emission tomography (PET) assesses biochemical processes in the living subject, producing images of function rather than form. Using PET, physicians are able to obtain not the anatomical information provided by other medical imaging techniques, but pictures of physiological activity. In metaphoric terms, traditional imaging methods supply a map of the body's roadways, its, anatomy; PET shows the traffic along those paths, its biochemistry. This document discusses the principles of PET, the radiopharmaceuticals in PET, PET research, clinical applications of PET, the cost of PET, training of individuals for PET, the role of the United States Department of Energy in PET, and the futures of PET. 22 figs.

  1. Etileno glicol na criopreservação de sêmen canino Ethylene glycol on canine semen cryopreservaton

    Directory of Open Access Journals (Sweden)

    Marcio Pereira Soares

    2002-08-01

    Full Text Available O objetivo deste trabalho foi avaliar a utilização do etileno glicol, adicionado ao meio Tris-gema, na criopreservação de sêmen canino, considerando os seus efeitos sobre a motilidade, o vigor e a morfologia espermática pré e pós-congelamento. Como doadores, utilizaram-se quatro cães da raça Pastor Alemão coletados por manipulação digital os quais no ejaculado apresentaram padrões mínimos de 90% de motilidade, cinco de vigor espermático (0 - 5 e no máximo 35% de defeitos morfológicos totais. As concentrações de etileno glicol testadas foram de 0, 25; 0,5 e 1,0M, sendo empregados como controle 0,8M de glicerol. Foram feitas cinco avaliações de motilidade e vigor, respectivamente, na obtenção da fração rica, depois da primeira diluição, ao atingir 4°C, após uma hora de estabilização a 4°C e no descongelamento. Avaliou-se a morfologia espermática em sêmen a fresco e após o descongelamento das amostras de cada tratamento. Não houve diferença na motilidade e na morfologia espermática dos grupos após o descongelamento. No vigor espermático pós- descongelamento, as concentrações de 0,25 e 0,5M de etileno glicol foram semelhantes entre si e com a concentração de 0,8M de glicerol (controle, mas diferiram da concentração de 1M, a qual apresentou vigor inferior ao controle. Conclui-se que, para a criopreservação de sêmen canino, o glicerol 0,8M pode ser substituído pelo etileno glicol nas concentrações de 0,25, 0,5 e 1,0M.The objective of the present work was to evaluate the efficiency of ethylene glycol on criopreservation of canine semen, considering its possible deleterious effects upon semen motility, vigor and morphology at the pre and post freezing stages, using a tris-egg yolk extender. Four adult german shepards were used as donors. Samples were obtained by digital manipulation, and only ejaculates presenting a minimum of 90% motility and 5 (0-5 vigor and no more than 35% of total morphological

  2. Pet Allergy

    Science.gov (United States)

    ... develop bacterial infections of the sinuses, such as sinusitis. Asthma People with asthma and pet allergy often have difficulty managing asthma symptoms. They may be at risk of asthma attacks that require immediate medical treatment or emergency care. Prevention If you don't ...

  3. Determinação da variação da viscosidade intrínseca do poli (tereftalato de etileno de embalagens Determination of intrinsic viscosity variation for polyethyelene terephthalate's bottles

    Directory of Open Access Journals (Sweden)

    Sandro D. Mancini

    2004-06-01

    Full Text Available O mercado de embalagens de poli(tereftalato de etileno -PET- para acondicionamento de refrigerantes, água mineral, sucos concentrados e óleos comestíveis apresenta polímeros de diferentes tipos, que foram desenvolvidos para personalizar o atendimento a clientes desejosos de propriedades melhores e mais específicas, principalmente em termos de massa molar. No caso do PET, assim como na indústria da reciclagem do polímero, o ensaio de viscosidade intrínseca é muito usado para determinar a massa molar. Este trabalho apresenta os resultados de viscosidade intrínseca de PET advindo de embalagens de várias marcas de refrigerantes, sucos e óleos de soja. Amostras de cada embalagem foram dissolvidas em solução de fenol-tetracloroetano (60:40 em peso e o fluxo das mesmas em um viscosímetro Cannon-Fenske a 30 °C para medir a viscosidade relativa, que foi convertido para viscosidade intrínseca. Os resultados mostraram uma variação no valor da propriedade conforme se variava o volume, tipo e a marca do produto envasado. Para as 21 amostras analisadas, os resultados variaram de 0,70 a 0,79 dL/g. Portanto, uma melhor seleção das embalagens pode ajudar os recicladores na obtenção de produtos melhores, com menor variação na massa molar. Os valores de densidade obtidos apresentaram uma pequena variação, que torna-se maior quando transformados em cristalinidade.The market of polyethylene terephthalate (PET bottles presents polymers of different types, which have been developed in order to provide the client with products with improved properties, mainly in respect of molar mass. In the case of PET, as well as in the recycling industry of this polymer, the test of intrinsic viscosity is widely used to determine molar mass. This study presents the results of intrinsic viscosity and density for PET bottles of soft-drinks, juices and soy-bean oils. Samples of each bottle were dissolved in 60-40 phenol-tetrachloroethane solution and flowed

  4. Etileno e peróxido de hidrogênio na formação de aerênquima em milho tolerante a alagamento intermitente

    Directory of Open Access Journals (Sweden)

    Marinês Ferreira Pires

    2015-09-01

    Full Text Available Resumo:O objetivo deste trabalho foi avaliar o papel do etileno e do peróxido de hidrogênio (H2O2 na formação do aerênquima em ciclos de seleção genética da cultivar de milho BRS 4154, sob alagamento. Plantas dos ciclos C1 e C18 foram submetidas a alagamento por 7 dias, com coleta das raízes aos 0 (controle, sem alagamento, 1 e 7 dias. Foram analisados: a expressão gênica das enzimas ACC sintase (ACS, ACC oxidase (ACO, dismutase do superóxido (SOD e peroxidase do ascorbato (APX; a produção de etileno e o conteúdo de H2O2; a atividade da enzima ACO; e a proporção de aerênquima no córtex. Não houve expressão de ACS e ACO. Houve variação na atividade de ACO e na produção de etileno. A expressão da SOD foi maior em plantas C1 e a da APX, em C18, com redução aos 7 dias. O conteúdo de H2O2 não diferiu entre os tratamentos. A proporção de aerênquima aumentou com o tempo, tendo sido maior em plantas C18 e relacionada à taxa de formação do aerênquima. O tempo de alagamento e o nível de tolerância do ciclo de seleção influenciam a produção do etileno. A expressão da APX indica maior produção de H2O2 no início do alagamento.

  5. Efeito da adição de PHB na cristalização a frio do PET Effect of PHB on cold crystallization of PET

    Directory of Open Access Journals (Sweden)

    Ana C. Brito

    2012-01-01

    Full Text Available O presente trabalho investigou o efeito da adição de baixas concentrações (0,5 e 1,0% de poli(3-hidroxibutirato (PHB na cristalização isotérmica a frio do poli(tereftalato de etileno (PET. As curvas de energia foram obtidas por calorimetria exploratória diferencial (DSC e a cinética de cristalização foi analisada pelo método de Avrami. Dois estágios de cristalização foram observados. Os resultados mostraram que o PHB promove alterações na taxa de cristalização do PET, como verificado por mudanças nos tempos para se atingir 1, 10, 30, 50 e 99% de cristalinidade relativa. As energias de ativação para o primeiro e segundo estágios da cristalização foram determinadas através das curvas de Arrhenius, sendo praticamente independentes da presença de PHB nas misturas PET/PHB. As temperaturas de fusão de equilíbrio foram determinadas de acordo com o procedimento de Hoffman e Weeks; as misturas PET/PHB apresentaram valores mais elevados deste parâmetro sugerindo que o PHB altera a estrutura cristalina do PET.The present work is concerned with the effect of low concentrations (0.5 e 1.0% of poly(3-hydroxybutirate (PHB on the isothermal cold crystallization of poly(ethylene terephthalate (PET. Energy curves were obtained by differential scanning calorimetry (DSC and the kinetics of the crystallization was analyzed using Avrami's method. Two crystallization stages were observed. Results showed that the presence of PHB affects the crystallization rate of PET, as verified by changes in the time needed to reach 1, 10, 30, 50 and 99% of crystallinity. Activation energies for the two crystallization stages were computed using Arrhenius plots; PET/PHB mixtures showed slightly smaller values. The equilibrium melting temperatures were estimated according to the procedure of Hoffman and Weeks; the higher values obtained for the PET/PHB mixtures suggest that PHB affects the crystalline structure of PET.

  6. Pet Problems at Home: Pet Problems in the Community.

    Science.gov (United States)

    Soltow, Willow

    1984-01-01

    Discusses problems of pets in the community, examining the community's role related to disruptive pets and pet overpopulation. Also discusses pet problems at home, offering advice on selecting a pet, meeting a pet's needs, and disciplining pets. Includes a list of books, films/filmstrips, teaching materials, and various instructional strategies.…

  7. Pet Bonding and Pet Bereavement among Adolescents.

    Science.gov (United States)

    Brown, Brenda H.; And Others

    1996-01-01

    Studied adolescent-pet bonding and bereavement following pet loss (n=55). Hypothesized that highly-bonded adolescents experience more intense grief when a pet dies than do those less bonded; degree of bonding is greater for girls than for boys; and intensity of bereavement is greater for girls than for boys. Results supported the hypotheses. (RB)

  8. Brain PET scan

    Science.gov (United States)

    ... have false results on a PET scan. Blood sugar or insulin levels may affect the test results in people with diabetes . PET scans may be done along with a CT scan. This combination scan is called a PET/CT. Alternative Names Brain positron emission tomography; PET scan - brain References Chernecky ...

  9. Aplicação de 1-metilciclopropeno associado ao etileno para minimizar seus efeitos na inibição do amadurecimento do mamão 'golden'

    Directory of Open Access Journals (Sweden)

    Marcos José Trevisan

    2013-06-01

    Full Text Available O objetivo deste trabalho foi estudar a fisiologia e a conservação pós-colheita de mamões 'Golden', submetidos à aplicação simultânea de 1-metilciclopropeno e etileno. Os frutos foram provenientes de cultivo comercial no Espírito Santo, no estádio de maturação 1. Os tratamentos foram compostos pelas seguintes combinações de 1-MCP (nL. L-1 + etileno (µL. L-1: 0+0; 100+0; 100+2,5; 100+5 e 100+10. Os tratamentos com 1-MCP e 1-MCP mais 2,5 µL. L-1 de etileno foram os que mais retardaram a perda da firmeza e a mudança da cor. Foi observada diferença na atividade respiratória entre o controle e os demais tratamentos. Inicialmente, a produção de etileno foi maior nos frutos do controle e menor naqueles com 1-MCP, a qual aumentou a partir do 10º dia. Não houve diferença no teor de sólidos solúveis entre os tratamentos. Quanto ao teor de ácido ascórbico, tratamentos com 1-MCP e 1-MCP mais 2,5 µL. L-1 de etileno apresentaram os teores mais elevados. Os tratamentos apresentaram notas de aparência acima de quatro ao final do armazenamento, ou seja, com boa aparência. Com estes resultados, é possível afirmar que existe potencial de uso do 1-MPC associado ao etileno, nos estádios iniciais de maturação do mamão 'Golden', para aumentar sua vida pós-colheita.

  10. Tejido óseo y apósito biológico esterilizados con gas óxido de etileno Tesis presentada en opción al grado científico Doctor en Ciencias Médicas

    OpenAIRE

    Jacas Torné, Manuel

    2014-01-01

    Introducción: En Cuba tradicionalmente se ha empleado las radiaciones Gamma para esterilizar el tejido óseo y la piel porcina. Con el propósito de buscar una alternativa a su empleo se estudió el gas óxido de etileno (OtE), nunca antes empleado en Cuba con esos fines. Objetivo general: Evaluar la efectividad del gas óxido de etileno como método esterilizante del tejido óseo esponjoso y la piel porcina. Metodología de la investigación: Se realizó un estudio experimental In Vitro d...

  11. Efeitos do processamento químico e da esterilização em Óxido de etileno em osso cortical e esponjoso de ratas: estudo com microscopia de luz e eletrônica de varredura

    OpenAIRE

    Castiglia, Marcello Teixeira; Silva, Juliano Voltarelli F. da; Thomazini,José Antonio; Volpon, José Batista

    2009-01-01

    OBJETIVO: Avaliar, sob o ponto de vista microscópico, modificações estruturais do osso esponjoso e cortical, após serem submetidos a processamento químico e esterilização em óxido de etileno. MÉTODOS: Amostras de osso esponjoso e cortical foram obtidas de fêmures de ratas albinas jovens (Wistar)e separadas em quatro grupos contendo osso cortical e esponjoso: I- Fragmentos secos em estufa; II- Fragmentos secos em estufa e esterilizados em óxido de etileno; III- Fragmentos processados quimicame...

  12. Viabilidade in vitro do espermatozóide canino congelado em diluidor tris-frutose-ácido cítrico com etileno glicol

    Directory of Open Access Journals (Sweden)

    Camila Infantosi Vannucchi

    1999-01-01

    Full Text Available A utilização de sêmen congelado tornou-se extremamente comum na prática da inseminação artificial em cães, estimulando a pesquisa de métodos de congelação e diluidores. Neste estudo foram avaliadas as propriedades criopreservativas do etileno glicol na concentração final de 5%, utilizado em 3 diferentes protocolos de congelação. No Método I, uma parte de sêmen foi adicionada a duas partes de tris-frutose-ácido cítrico, contendo 7,5% de etileno glicol e congelado sem prévia refrigeração. No Método II, uma parte de sêmen foi adicionada a duas partes de tris-frutose-ácido cítrico contendo 7,5% de etileno glicol e resfrigerado até 5ºC por 1 hora antes da congelação. No Método III, uma parte de sêmen foi adicionada a uma parte de tris-frutose-ácido cítrico sem etileno glicol e refrigerado até 5ºC por 1 hora, sendo em seguida adicionada uma parte de tris-frutose-ácido cítrico, previamente refrigerado até 5ºC, contendo 15% de etileno glicol, mantido a 5ºC por mais 1 hora e congelado. Para a congelação em cada método, o sêmen foi envasado em palhetas plásticas de 0,5 ml, colocadas em vapor de nitrogênio a 5 cm da coluna líquida por 20 minutos, mergulhadas no nitrogênio líquido e armazenadas. Todas as amostras foram descongeladas em banho-maria a 37ºC durante 30 segundos e imediatamente avaliadas. O Método III não apresentou decréscimo significante da motilidade retilínea progressiva após a descongelação e apresentou os melhores resultados para o vigor espermático, comparando-se aos demais métodos. Entretanto, os 3 métodos não apresentaram diferença significativa com relação aos defeitos espermáticos pós-descongelação. Os tipos de defeitos mais freqüentemente encontrados foram cabeça solta normal, cauda dobrada, fortemente dobrada e fortemente enrolada. Foi possível concluir que o tempo de equilíbrio maior no diluidor tris-frutose-ácido cítrico seguido pela diluição em etileno

  13. Análise termodinâmica do comportamento mecânico na região elástica de blendas de poli (tereftalato de etileno reciclado e poliolefinas recicladas Thermodynamic analysis of mechanical behaviour in the elastic region of blends of recycled poly (ethylene terephthalate and recycled polyolefins

    Directory of Open Access Journals (Sweden)

    José M. Marconcini

    2006-12-01

    Full Text Available Este trabalho descreve o estudo de blendas de poli(tereftalato de etileno reciclado e poliolefinas recicladas, com e sem adição de polipropileno funcionalizado com anidrido maleico e poli(etileno-co-octeno-1 utilizando ensaios mecânicos e microscopia eletrônica de varredura. Foi aplicado um formalismo termodinâmico com base na função trabalho de Helmholtz para o comportamento mecânico na região elástica, correlacionando-se com o armazenamento de energia elástica para os materiais estudados. Também foi analisada a dissipação de energia relativa ao fenômeno elasto-plástico na região de baixas deformações. Para as blendas estudadas, observou-se que o armazenamento de energia e o efeito do compatibilizante são muito mais acentuados na região rica em poliolefinas, corroborando com as imagens da morfologia observadas via microscopia eletrônica. A análise termodinâmica apresentada mostrou-se uma ferramenta útil e confiável e de baixo custo, para avaliar o efeito de compatibilização de sistemas poliméricos imiscíveis. No presente trabalho, particularmente para a avaliação do comportamento mecânico de misturas de materiais "commodities" reciclados.This work describes the study using mechanical tests with the blend of recycled poly(ethylene terephthalate (PET and recycled polyolefin with and without the addition of polypropylene grafted with maleic anhydride and poly(ethylene-co-octene-1. A thermodynamic approach based on the Helmholtz work function was applied in the analysis of mechanical tests, correlating the effects of energy storage and from the compatibilizer on the elastic region of the materials. For the system studied, the polyolefin-rich region shows higher storage of elastic energy corroborating the morphology images obtained from SEM analysis. The thermodynamic analysis seems a useful tool to evaluate the compatibilizer effect in polymeric immiscible blends. In this work, more specifically, this method was

  14. Disaster Preparedness for Your Pet

    Science.gov (United States)

    ... for pets Louisiana State University College of Veterinary Medicine: Manual for Animal Shelters during a Disaster Ready Wrigley Pet Stories After the Storm: Pets and Preparedness Pet Preparedness Features Media Sign up for Features ...

  15. Polineuropatia devida ao óxido de etileno registro de caso com estudo clínico, eletrofisiológico e histopatológico

    OpenAIRE

    Freitas,Marcos R. G. de; Nascimento, Osvaldo J.M.; Leila Chimelli

    1991-01-01

    Os autores referem-se a caso de um jovem que, trabalhando em fábrica de esterilização de artigos médicos e em contato diário com o óxido de etileno, desenvolveu leve polineuropatia sensitivo-motora. Os estudos eletrofisiológicos evidenciaram neuropatia por degeneração axonal. A biópsia do nervo sural mostrou discreta perda de fibras mielínicas e sinais de degeneração e regeneração axonal. Este é o primeiro caso desta afecção descrita em nosso meio.

  16. DESARROLLO DE UN PROGRAMA PARA ESTUDIAR EL COMPORTAMIENTO DE UNA COLUMNA DE FRACCIONAMIENTO ETANO/ETILENO DE UNA PLANTA DE OLEFINAS

    OpenAIRE

    González,Patricia; ALCIATURI, Carlos

    2012-01-01

    En este trabajo se presenta el desarrollo de programas para el estudio del comportamiento de una columna de fraccionamiento Etano/Etileno, perteneciente a una planta de Olefinas. Se utilizaron una red neuronal (RNA) del tipo multicapas con propagación hacia adelante y el algoritmo de mínimos cuadrados parciales (PLS) con este propósito. El entrenamiento de la red neuronal y la obtención del modelo PLS se realizaron con datos experimentales de la planta. Estos datos experimentales se dividiero...

  17. Compatibilidades e incompatibilidades entre radiação gama e óxido de etileno como métodos sucessivos de esterilização

    OpenAIRE

    Rafael Queiroz de Souza; Kazuko Uchikawa Graziano

    2010-01-01

    A dúvida sobre a questão da re-esterilização de artigos confeccionados com cloreto de polivinila (PVC), esterilizados em radiação gama (RG) e posteriormente em óxido de etileno (EO) persiste até os dias atuais. Por meio da revisão integrativa da literatura, este artigo analisou estudos que evidenciaram compatibilidades e incompatibilidades entre os processos de esterilização com RG e EO quando utilizados como métodos sucessivos de esterilização. Foram analisados 7 estudos. Constatou-se que há...

  18. Heart PET scan

    Science.gov (United States)

    ... nuclear medicine scan; Heart positron emission tomography; Myocardial PET scan ... A PET scan requires a small amount of radioactive material (tracer). This tracer is given through a vein (IV), ...

  19. Pets and Parasites

    Science.gov (United States)

    ... oral contact with your pet. Don’t share food or kiss your pet on the mouth. Pregnant women and people who have weakened immune systems should never clean out cat litter boxes or handle cat feces. They can ...

  20. Healthy Pets and People

    Science.gov (United States)

    ... Your Pet Healthy Whether you have a dog, cat, horse, parakeet, gerbil, or bearded dragon, providing regular, life-long veterinary care is important to having a healthy pet and a healthy family. Regular veterinary visits are essential to good pet health. Talk to your pet’s veterinarian about ...

  1. Citotoxicidade de tubos de PVC esterilizados em óxido de etileno após exposição à radiação gama Citotoxicidad de tubos de PVC esterilizados en óxido de etileno luego de exposición a la radiación gamma Cytotoxicity of PVC tubes sterilized in ethylene oxide after gamma radiation exposure

    National Research Council Canada - National Science Library

    Rafael Queiroz de Souza; Kazuko Uchikawa Graziano; Tamiko Ichikawa Ikeda; Cláudia Regina Gonçalves; Áurea Silveira Cruz

    2013-01-01

    Materiais esterilizados em raios gama, ao serem re-esterilizados em óxido de etileno (EO), formam substâncias tóxicas? Esta questão norteou o objetivo deste estudo, que foi investigar o potencial efeito...

  2. Estrutura da cadeia reversa: "caminhos" e "descaminhos" da embalagem PET Structure of the reverse chain: "ways" of PET packing

    Directory of Open Access Journals (Sweden)

    Sylmara Lopes Francelino Gonçalves-Dias

    2006-12-01

    Full Text Available O trabalho propõe-se a discutir as possibilidades, limites e desafios da reciclagem de PET - Politereftalato de Etileno. Como fundamentação teórico-conceitual, recorre à discussão sobre a natureza e o alcance da logística reversa, analisando as estratégias para estruturação da cadeia de reciclagem. A pesquisa é de caráter exploratório, com adoção de diferentes estratégias para a coleta de dados, envolvendo fontes secundárias produzidas por órgãos públicos, instituições especializadas e mídia, e ainda entrevistas semi-estruturadas com especialistas na área. Os resultados apontam que múltiplos atores estão envolvidos na estrutura da cadeia reversa do PET e que, apesar do avanço no volume de reciclagem, nenhum dos setores, seja público ou privado, consegue individualmente organizar-se para o alcance da efetividade operacional e ambiental desejável no cenário brasileiro. O alcance de bons resultados depende, sobretudo, do investimento nos dois extremos da cadeia reversa: na coleta seletiva e no mercado para o produto reciclado.The work discuss the possibilities, limits and challenges of the recycling of PET packing in the Brazilian case. The authors analyze the nature and the function of the reverse logistics and its strategies for articulation of the recycling chain. The research is based in the exploratory methodological approach, with adoption of different strategies for the collection of data, involving secondary sources produced by public institutions, specialized organizations and media, and still, interviews semi-structured with specialists in the area. The results point that the Brazilian public and private sectors doesn’t get to organize this activity in the desirable environmental scale. Good performances in the PET packing reverse chain depends on investing in the selective collection and in the market for the recycled products.

  3. O uso do pet em telhas translúcidas visando o conforto natural lumínico e térmico

    OpenAIRE

    CAVALCANTE, Christiane Rosa de Paiva

    2011-01-01

    O PET, tereftalato de etileno, é o material mais conhecido e apropriado na fabricação de várias embalagens de produtos alimentícios, entre as quais se destacam as garrafas de refrigerante. A correta gestão dos resíduos sólidos urbanos, com a transformação desses resíduos para o retorno ao uso, e a educação ambiental são tarefas essenciais para garantir o aproveitamento da totalidade da vida útil daquele material e evitar que seja ele o foco de contaminação ambiental. Do ponto d...

  4. Preservação da qualidade pós-colheita de kiwi 'bruno' pelo controle do etileno Postharvest quality preservation of 'bruno' kiwifruit by ethylene control

    Directory of Open Access Journals (Sweden)

    Marcelo José Vieira

    2010-06-01

    Full Text Available Objetivou-se determinar os efeitos do 1-MCP sobre a conservação pós-colheita de kiwi, cultivar Bruno, armazenado sob atmosfera do ar (AA e atmosfera controlada (AC. Os frutos foram colhidos em abril de 2003 e 2004. Três dias após a colheita, parte dos frutos foi tratada com 1,0 µL.L-1 de 1-MCP e armazenada sob atmosfera do ar (AA e AC com baixo etileno. O tratamento com 1-MCP retardou o aumento da taxa de produção de etileno e reduziu a respiração após remoção de câmara fria, resultando assim no retardo da perda de firmeza da polpa e na redução do desenvolvimento de pericarpo translúcido e senescente. O tratamento com 1-MCP não apresentou efeito significativo sobre os teores de sólidos solúveis. Frutos armazenados sob AA apresentaram alto metabolismo, resultando em baixo potencial de armazenamento, mesmo na presença do 1-MCP. Máxima conservação da qualidade pós-colheita de kiwi 'Bruno' foi observada em frutos tratados com 1-MCP e armazenados sob AC com baixo etileno.This research was carried out to study the effects of 1-MCP on postharvest quality preservation of kiwi 'Bruno' storage under controlled atmosphere and air. Fruits were harvested in April of 2003 and 2004. Three days after harvesting, part of the fruits was treated with 1.0 µL.L-1 of 1-MCP, while the other part remained untreated (control, and then both lots were stored under air (AA and CA with low ethylene. The treatment with 1-MCP delayed the increase in ethylene production rate and reduced respiration of the fruit after removal from cold storage. This was associated with a delay of loss in flesh firmness and a reduction of pericarp translucent and senescent. Treatment with 1-MCP showed no significant effect on SS content. Fruit stored under AA showed high metabolism, resulting in a low storage potential, evenwhentreated with 1-MCP. The greatest benefits on postharvest quality preservation of kiwifruit 'Bruno' was achieved in fruit treated with 1-MCP and

  5. Sensory analysis of pet foods.

    Science.gov (United States)

    Koppel, Kadri

    2014-08-01

    Pet food palatability depends first and foremost on the pet and is related to the pet food sensory properties such as aroma, texture and flavor. Sensory analysis of pet foods may be conducted by humans via descriptive or hedonic analysis, pets via acceptance or preference tests, and through a number of instrumental analysis methods. Sensory analysis of pet foods provides additional information on reasons behind palatable and unpalatable foods as pets lack linguistic capabilities. Furthermore, sensory analysis may be combined with other types of information such as personality and environment factors to increase understanding of acceptable pet foods. Most pet food flavor research is proprietary and, thus, there are a limited number of publications available. Funding opportunities for pet food studies would increase research and publications and this would help raise public awareness of pet food related issues. This mini-review addresses current pet food sensory analysis literature and discusses future challenges and possibilities. © 2014 Society of Chemical Industry.

  6. Laboratory and cyclotron requirements for PET research

    Energy Technology Data Exchange (ETDEWEB)

    Schlyer, D.J.

    1993-06-01

    This report describes four types of PET facilities: Clinical PET with no radionuclide production; clinical PET with a small accelerator; clinical PET with research support; and research PET facilities. General facility considerations are also discussed.

  7. Polineuropatia devida ao óxido de etileno registro de caso com estudo clínico, eletrofisiológico e histopatológico

    Directory of Open Access Journals (Sweden)

    Marcos R. G. de Freitas

    1991-12-01

    Full Text Available Os autores referem-se a caso de um jovem que, trabalhando em fábrica de esterilização de artigos médicos e em contato diário com o óxido de etileno, desenvolveu leve polineuropatia sensitivo-motora. Os estudos eletrofisiológicos evidenciaram neuropatia por degeneração axonal. A biópsia do nervo sural mostrou discreta perda de fibras mielínicas e sinais de degeneração e regeneração axonal. Este é o primeiro caso desta afecção descrita em nosso meio.

  8. Efeito compatibilizante de uma argila organofílica na blenda PLA/terpolímero (etileno/acrilato de metila/metacrilato de glicidila

    Directory of Open Access Journals (Sweden)

    Gustavo F. Brito

    2013-01-01

    Full Text Available Neste trabalho, nanocompósitos obtidos a partir de blendas entre o poli (ácido lático e o terpolímero (etileno/acrilato de metila/metacrilato de glicidila foram confeccionados. A argila organofílica comercial Cloisite 20A foi utilizada como nanocarga. Interações entre a argila e o terpolímero foram investigadas por reometria de torque. As estruturas dos nanocompósitos foram determinadas por difração de raios X, sendo obtidos nanocompósitos intercalados e microcompósitos. A atuação da argila como agente compatibilizante foi evidenciada por fotomicrografias obtidas por microscopia eletrônica de varredura. As propriedades mecânicas das blendas mostraram-se dependentes tanto da morfologia como do grau de dispersão da argila.

  9. Eletrodeposição de chumbo sobre Carbono Vítreo, em sistema Ácido, Alcalino e com a influência do Etileno Glicol

    OpenAIRE

    SILVA, Gilvaldo Gentíl da

    2008-01-01

    A eletrodeposição de chumbo, sobre carbono vítreo, em meios ácidos (HBF4) e alcalinos (KOH) e sobre a influência do etileno glicol, em concentração variada, foi estudada através de voltametria cíclica e cronoamperometria. Os resultados experimentais mostram claramente que a eletrodeposição de chumbo, sobre o carbono vítreo é um processo controlado por nucleação com um mecanismo de crescimento em três dimensões (3D) A voltametria cíclica permitiu uma avaliação das sobretensões e...

  10. Aspectos toxicológicos de la exposición al óxido de etileno Aspectos toxicológicos da exposição ao óxido de etileno Toxicological aspects of the exposure to ethylene oxide

    Directory of Open Access Journals (Sweden)

    Andrés Prat Marín

    1987-12-01

    Full Text Available En este trabajo se revisan los principales riesgos de la utilización del óxido de etileno como agente esterilizante del material médico-quirúrgico. Resaltando los efectos tóxicos, mutagénicos, teratogénicos y cancerígenos como los más importantes, enfatizando en la necesidad de adoptar medidas de prevención para controlar dichos riesgos.Neste trabalho são revisados os principais riscos de utilização do óxido de etileno como agente esterilizante do material médico-cirúrgico. Ressaltam-se efeitos tóxicos, mutagênicos, teratogênicos e cancerígenos como sendo os mais importantes, enfatizando a necessidade de adotar medidas de prevenção para controlar os referidos riscos.Some important aspects of the use of ethylene oxide as a sterilizing agent for medical instruments are reviewed in this paper. Toxic, mutagenic, teratogenic and carcinogenic effects are the main risks described and emphasis it given to preventive mesures.

  11. Integrated PET/MR.

    Science.gov (United States)

    Quick, Harald H

    2014-02-01

    Integrated whole-body PET/MR hybrid imaging combines excellent soft tissue contrast and various functional imaging parameters provided by MR with high sensitivity and quantification of radiotracer metabolism provided by positron emission tomography (PET). While clinical evaluation now is under way, integrated PET/MR demands for new technologies and innovative solutions, currently subject to interdisciplinary research. Attenuation correction of human soft tissues and of hardware components has to be MR-based to maintain quantification of PET imaging because computed tomography (CT) attenuation information is missing. This brings up the question of how to provide bone information with MR imaging. The limited field-of-view in MR imaging leads to truncations in body imaging and MR-based attenuation correction. Another research field is the implementation of motion correction technologies to correct for breathing and cardiac motion in view of the relatively long PET data acquisition times. Initial clinical applications of integrated PET/MR in oncology, neurology, pediatric oncology, and cardiovascular disease are highlighted. The hybrid imaging workflow here has to be tailored to the clinical indication to maximize diagnostic information while minimizing acquisition time. PET/MR introduces new artifacts that need special observation and innovative solutions for correction. Finally, the rising need for appropriate phantoms and standardization efforts in PET/MR hybrid imaging is discussed. Copyright © 2013 Wiley Periodicals, Inc.

  12. My Pet Rock

    Science.gov (United States)

    Lark, Adam; Kramp, Robyne; Nurnberger-Haag, Julie

    2008-01-01

    Many teachers and students have experienced the classic pet rock experiment in conjunction with a geology unit. A teacher has students bring in a "pet" rock found outside of school, and the students run geologic tests on the rock. The tests include determining relative hardness using Mohs scale, checking for magnetization, and assessing luster.…

  13. Effect of Ethylene Inhibitors on Quality Attributes of Apricot cv. Modesto and Patterson during Storage Efecto de los Inhibidores de Etileno sobre Atributos de Calidad de Damascos, Variedades Modesto y Patterson durante Almacenamiento

    Directory of Open Access Journals (Sweden)

    Héctor Valdés

    2009-06-01

    Full Text Available Apricot (Prunus armeniaca L. fruit are highly susceptible to flesh softening, loss of flavor and fruit decay, particularly during postharvest storage. Most of these quality changes observed during fruit ripening are under ethylene regulation. We performed a study with the objective of determining the effect of 1-methylcyclopropene (1-MCP and aminoethoxyvinylglycine (AVG applications on quality attributes of Modesto and Patterson apricot cultivars. 1-MCP was applied at a rate of 1000 and 10 000 nL L-1 of SmartFresh™, and AVG at a rate 100 and 1000 mg L-1 of Retain®. Quality evaluations were performed after 20 and 30 days of cold storage and after a shelf-life period of 3-4 days at 20 °C. In general, both ethylene inhibitors were effective in reducing the ethylene production rate, especially in Patterson. Fruit softening and color development showed ethylene-dependent behavior, with significant reductions for both varieties in fruit treated with 1-MCP and AVG. On the other hand, soluble solids concentration and titratable acidity showed an ethylene-independent pattern, i.e. they were not affected by ethylene inhibitors applications. Among volatile compounds identified, esters and aldehydes showed ethylene-dependent behavior in both varieties. On the other hand, alcohols and terpenes were not affected by ethylene inhibition, suggesting ethylene-independent behavior.El damasco (Prunus armeniaca L. es muy susceptible al ablandamiento de la pulpa, pérdida de sabor y pudriciones, especialmente durante postcosecha. Muchos de estos cambios que ocurren durante maduración son regulados por etileno. El objetivo del presente trabajo fue determinar el cambio de la calidad de damascos var. Modesto y Patterson tratados con 1-metilciclopropeno (1-MCP y aminoetoxivinilglicina (AVG. Las dosis utilizadas fueron de 1000 y 10 000 nL L-1 de 1-MCP (SmartFresh™, 100 y 1000 mg L-1 de AVG (Retain® 15% p/p y su respectivo testigo. Las evaluaciones se realizaron

  14. Healthy pets, healthy people.

    Science.gov (United States)

    Wong, S K; Feinstein, L H; Heidmann, P

    1999-08-01

    Zoonoses, diseases that can be transmitted from animals to humans, can pose serious health risks to immunocompromised people. Although pets can carry zoonoses, owning and caring for animals can benefit human health. Information exists about preventing transmission of zoonoses, but not all physicians and veterinarians provide adequate and accurate information to immunocompromised pet owners. This disease prevention/health promotion project provides physicians and veterinarians with information, created specifically to share with patients and clients, about the health risks and benefits of pet ownership. Further, "Healthy Pets, Healthy People" encourages communication between veterinarians, physicians, clients, and patients and can serve as a model program for a nation-wide effort to aid health professionals in making recommendations about pet ownership for immunocompromised people.

  15. Usage of Recycled Pet

    Directory of Open Access Journals (Sweden)

    A. Ebru Tayyar

    2010-01-01

    Full Text Available The increasing industrialization, urbanization and the technological development have caused to increase depletion of the natural resources and environmental pollution's problem. Especially, for the countries which have not enough space recycling of the waste eliminating waste on regular basis or decreasing the amount and volume of waste have provided the important advantages. There are lots of studies and projects to develop both protect resources and prevent environmental pollution. PET bottles are commonly used in beverage industry and can be reused after physical and chemical recycling processes. Usage areas of recycled PET have been developed rapidly. Although recycled PET is used in plastic industry, composite industry also provides usage alternatives of recycled PET. Textile is a suitable sector for recycling of some plastics made of polymers too. In this study, the recycling technologies and applications of waste PET bottles have been investigated and scientific works in this area have been summarized.

  16. Evaluation of PET Scanner Performance in PET/MR and PET/CT Systems: NEMA Tests.

    Science.gov (United States)

    Demir, Mustafa; Toklu, Türkay; Abuqbeitah, Mohammad; Çetin, Hüseyin; Sezgin, H Sezer; Yeyin, Nami; Sönmezoğlu, Kerim

    2018-02-01

    The aim of the present study was to compare the performance of positron emission tomography (PET) component of PET/computed tomography (CT) with new emerging PET/magnetic resonance (MR) of the same vendor. According to National Electrical Manufacturers Association NU2-07, five separate experimental tests were performed to evaluate the performance of PET scanner of General Electric GE company; SIGNATM model PET/MR and GE Discovery 710 model PET/CT. The main investigated aspects were spatial resolution, sensitivity, scatter fraction, count rate performance, image quality, count loss and random events correction accuracy. The findings of this study demonstrated superior sensitivity (~ 4 folds) of PET scanner in PET/MR compared to PET/CT system. Image quality test exhibited higher contrast in PET/MR (~ 9%) compared with PET/CT. The scatter fraction of PET/MR was 43.4% at noise equivalent count rate (NECR) peak of 218 kcps and the corresponding activity concentration was 17.7 kBq/cc. Whereas the scatter fraction of PET/CT was found as 39.2% at NECR peak of 72 kcps and activity concentration of 24.3 kBq/cc. The percentage error of the random event correction accuracy was 3.4% and 3.1% in PET/MR and PET/CT, respectively. It was concluded that PET/MR system is about 4 times more sensitive than PET/CT, and the contrast of hot lesions in PET/MR was ~ 9% higher than PET/CT. These outcomes also emphasize the possibility to achieve excellent clinical PET images with low administered dose and/or a short acquisition time in PET/MR.

  17. Integrated PET/MR

    National Research Council Canada - National Science Library

    Quick, Harald H

    2014-01-01

    Integrated whole‐body PET/MR hybrid imaging combines excellent soft tissue contrast and various functional imaging parameters provided by MR with high sensitivity and quantification of radiotracer metabolism provided...

  18. Combined PET/MRI

    DEFF Research Database (Denmark)

    Bailey, D. L.; Pichler, B. J.; Gückel, B.

    2015-01-01

    This paper summarises key themes and discussions from the 4th international workshop dedicated to the advancement of the technical, scientific and clinical applications of combined positron emission tomography (PET)/magnetic resonance imaging (MRI) systems that was held in Tübingen, Germany, from...... February 23 to 27, 2015. Specifically, we summarise the three days of invited presentations from active researchers in this and associated fields augmented by round table discussions and dialogue boards with specific topics. These include the use of PET/MRI in cardiovascular disease, paediatrics, oncology......, neurology and multi-parametric imaging, the latter of which was suggested as a key promoting factor for the wider adoption of integrated PET/MRI. Discussions throughout the workshop and a poll taken on the final day demonstrated that attendees felt more strongly that PET/MRI has further advanced in both...

  19. Pet Disaster Preparedness

    Science.gov (United States)

    ... a Volunteer Volunteer Opportunities Volunteer to Sound the Alarm Sign in to Volunteer Connection About Us Our ... may be more comfortable together, be prepared to house them separately. Include your pets in evacuation drills ...

  20. Pet Allergy Quiz

    Science.gov (United States)

    ... of U.S. households include a member of the dog or cat family. Yet, millions of people suffer from pet allergies. Take this quiz to test your knowledge about popular myths as well as coping strategies related to ...

  1. Cold Weather Pet Safety

    Science.gov (United States)

    ... AVMA Who We Are Governance AVMA Careers AVMF Student AVMA (SAVMA) Allied Organizations AVMA Store (Products) Policy ... Protect family: Odds are your pet will be spending more time inside during the winter, so it's ...

  2. Redução da velocidade de cristalização a frio do PET na presença de poliestireno The reduction of the cold crystallization rate of Pet in the presence of polystyrene

    Directory of Open Access Journals (Sweden)

    Renate M. R. Wellen

    2007-06-01

    Full Text Available A cristalização a frio do poli(tereftalato de etileno (PET e de suas blendas com poliestireno (PS foi estudada utilizando calorimetria exploratória diferencial (DSC, análise dinâmico-mecânica (DMA, microscopia eletrônica de varredura (MEV e propriedades mecânicas. As blendas PET/PS formam misturas bifásicas, como confirmado por MEV e por DMA, onde fases distintas e duas Tg s foram observadas. Por outro lado, a determinação da temperatura de fusão de equilíbrio (Tmº do PET por DSC indicou uma diminuição neste parâmetro com a presença do PS, sugerindo que uma solubilidade limitada do PS no PET deve ocorrer. A presença de um componente não cristalizável como o PS, parcialmente solúvel em uma fase cristalizável como PET, reduz a habilidade de cristalização. Isto foi observado nas análises de DSC através do deslocamento dos picos de cristalização a frio do PET para temperaturas maiores e por uma redução na velocidade de cristalização a frio. A abordagem de Avrami foi utilizada para os estudos cinéticos em condições isotérmicas, mostrando que o processo de cristalização ocorre em dois estágios e que a constante de cristalização K diminuiu significativamente com a presença de poliestireno. Nas blendas PET/PS a presença de apenas 1% de PS retardou significantemente a cristalização do PET, em magnitude semelhante ao que ocorreu quando concentrações mais elevadas de PS foram utilizadas. Este comportamento é de grande importância industrial já que em baixa concentração de PS as propriedades mecânicas do PET não são afetadas, como também mostrado neste estudo.The cold crystallization of PET and its blends with polystyrene (PS was investigated by differential scanning calorimetry (DSC, dynamic mechanical thermal analysis (DMA, scanning electron microscopy (SEM and mechanical properties. PET/PS blends form separate phases, as confirmed by SEM and DMA, showing distinct phases and two glass transition

  3. Combined PET/MRI

    DEFF Research Database (Denmark)

    Bailey, D L; Pichler, B J; Gückel, B

    2018-01-01

    The 6th annual meeting to address key issues in positron emission tomography (PET)/magnetic resonance imaging (MRI) was held again in Tübingen, Germany, from March 27 to 29, 2017. Over three days of invited plenary lectures, round table discussions and dialogue board deliberations, participants c...... of response to pharmacological interventions and therapies. As such, PET/MRI is a key to advancing medicine and patient care....

  4. PET and Recycling

    OpenAIRE

    Funda Sevencan; Songul A. Vaizoglu

    2007-01-01

    This review aims to clarify the need of decreasing the environmental effects caused by human and draw attention to the increasing environmental effects of plastics wastes. Plastics consist of organic molecules with high density molecules or polymers. Main resources of plastics are the residue of oil rafineries. Several advantages of plastics, have increased the usage continuously. Polyethylene Terephthalate (PET) is the most commonly used plastics. PET is used to protect food, drinking water,...

  5. Pets and Parasites.

    Science.gov (United States)

    Juckett, G

    1997-11-01

    Which parasites can be transmitted by household cats and dogs? Certainly a variety of potentially dangerous helminths and protozoa can be transmitted to humans from pets but, for the most part, very special conditions must be present before this occurs. Small children, pregnant women and immunocompromised persons are three groups at greater potential risk than the general population. Infants and toddlers may contract visceral or cutaneous larva migrans, tapeworm infections and, rarely, other helminths or protozoa. Pregnant women and their offspring are at special risk for toxoplasmosis. Immunocompromised persons (including those with acquired immunodeficiency syndrome) are susceptible to multiple infections but especially to cryptosporidiosis, an underdiagnosed zoonosis present in contaminated water supplies. Other zoonotic infections (Echinococcosis, Dirofilariasis) rarely appear in the general population but, when they do occur, pose very real diagnostic challenges. The risk of disease transmission from pets can be minimized by taking a few simple precautions such as avoiding fecal-oral contact, not emptying the cat's litterbox if pregnant, washing hands carefully after handling pets, worming pets regularly and supervising toddler-pet interactions. In most cases, the psychologic benefits of pet ownership appear to outweigh the reducible risks of disease transmission.

  6. Extensão de Cadeia em Poli(Naftalato de Etileno pelo Fosfito de Trifenila Chain Extention of Poly(ethylene naphthalate with Triphenylphosphite

    Directory of Open Access Journals (Sweden)

    Marcos L. Dias

    2001-09-01

    Full Text Available O processamento reativo de poli(naftalato de etileno (PEN na presença de fostito de trifenila (TPP em um misturador interno acoplado ao reômetro de torque foi investigado. O acompanhamento do torque e da temperatura durante o processamento revelou a ocorrência de reações de extensão de cadeia. A massa molecular do poliéster aumentou com o tempo de processamento, passando por um máximo, após o qual começa a decrescer como resultado de degradação molecular acelerada pela presença de subprodutos da extensão de cadeia. A intensidade das reações de extensão de cadeia aumenta com o aumento do teor de TPP, da temperatura e do cisalhamento. Tanto a extensão de cadeia quanto a degradação ocorrem mais lentamente para o PEN que para o poli(tereftalato de etileno. A presença de TPP no material provoca modificações na Tg, devido a um efeito de plastificação, e aumenta a velocidade de cristalização.The reactive processing of poly(ethylene naphthalate (PEN in presence of triphenylphosphite (TPP was investigated. An internal mixer coupled to a torque rheometer was used to monitor changes of molecular mass and temperature during processing. The torque curves revealed that chain extension reactions took place. During the processing, there is an increase in the molecular weight of the polyester, which reaches a maximum and then decreases due to molecular degradation, accelerated by the presence of chain extention by-products. The intensity of the chain extention reaction increases when TPP content, temperature and shear rate rise. Chain extension and degradation rate are slower in PEN than in poly(ethylene terephthalate. The presence of low molecular weight by-products of chain extension in PEN causes changes in the Tg, due to plasticization effects, and increase the crystallization rate.

  7. Study on radio sterilization effects on recycled poly(ethyleneterephthalate)'s PET properties; Estudo do efeito da dose de radioesterilizacao sobre as propriedades dopoli(tereftalato de etileno) - PET reciclado

    Energy Technology Data Exchange (ETDEWEB)

    Isoldi, Ana Beatriz Godoy

    2003-07-01

    The packing are in constant development, in function, especially, theprocess of globalization. The opening of the brazilian market after currencystabilization, caused technological innovations, change of habits andcostumes of the population and environmental matters. Year after year,because of cost reductions, it became more extreme the hard study of thepolymeric materials and their copolymers, their possible blends and theirrecycling, always seeking a better wrapping of the products, especially whenit concerns to the food, increasing its shelf life. The process ofsterilization of foods and modification of polymers through radiation aretargets of growing interest by of the current industries linked to thenutrition and packing sectors. The objective of this paper is to characterizefour different kinds of samples of recycled poly(ethylene terephthalate) andto discuss the application of the radiation (electron beam) in thesterilization of polymer, evaluating the possible effects on theirproperties. (author)

  8. PET/MRI: Where might it replace PET/CT?

    Science.gov (United States)

    Ehman, Eric C; Johnson, Geoffrey B; Villanueva-Meyer, Javier E; Cha, Soonmee; Leynes, Andrew Palmera; Larson, Peder Eric Zufall; Hope, Thomas A

    2017-11-01

    Simultaneous positron emission tomography and MRI (PET/MRI) is a technology that combines the anatomic and quantitative strengths of MR imaging with physiologic information obtained from PET. PET and computed tomography (PET/CT) performed in a single scanning session is an established technology already in widespread and accepted use worldwide. Given the higher cost and complexity of operating and interpreting the studies obtained on a PET/MRI system, there has been question as to which patients would benefit most from imaging with PET/MRI versus PET/CT. In this article, we compare PET/MRI with PET/CT, detail the applications for which PET/MRI has shown promise and discuss impediments to future adoption. It is our hope that future work will prove the benefit of PET/MRI to specific groups of patients, initially those in which PET/CT and MRI are already performed, leveraging simultaneity and allowing for greater degrees of multiparametric evaluation. 5 Technical Efficacy: Stage 5 J. Magn. Reson. Imaging 2017;46:1247-1262. © 2017 International Society for Magnetic Resonance in Medicine.

  9. Citotoxicidade de tubos de PVC esterilizados em óxido de etileno após exposição à radiação gama

    Directory of Open Access Journals (Sweden)

    Rafael Queiroz de Souza

    2013-04-01

    Full Text Available Materiais esterilizados em raios gama, ao serem re-esterilizados em óxido de etileno (EO, formam substâncias tóxicas? Esta questão norteou o objetivo deste estudo, que foi investigar o potencial efeito citotóxico do PVC esterilizado em radiação gama e re-esterilizado em EO pelo método da difusão em ágar em culturas celulares. Nove tubos de PVC foram submetidos à esterilização em radiação gama e re-esterilizados em EO. Os tubos foram divididos em um total de 81 unidades de análise, que foram testadas de forma a representar as superfícies internas, externas e massa de cada tubo. Concluiu-se que os materiais de PVC esterilizados em Radiação Gama e consecutivamente re-esterilizados em EO não são citotóxicos.

  10. Citotoxicidade de tubos de PVC esterilizados em óxido de etileno após exposição à radiação gama

    Directory of Open Access Journals (Sweden)

    Rafael Queiroz de Souza

    Full Text Available Materiais esterilizados em raios gama, ao serem re-esterilizados em óxido de etileno (EO, formam substâncias tóxicas? Esta questão norteou o objetivo deste estudo, que foi investigar o potencial efeito citotóxico do PVC esterilizado em radiação gama e re-esterilizado em EO pelo método da difusão em ágar em culturas celulares. Nove tubos de PVC foram submetidos à esterilização em radiação gama e re-esterilizados em EO. Os tubos foram divididos em um total de 81 unidades de análise, que foram testadas de forma a representar as superfícies internas, externas e massa de cada tubo. Concluiu-se que os materiais de PVC esterilizados em Radiação Gama e consecutivamente re-esterilizados em EO não são citotóxicos.

  11. Selecting Safe Pets (For Parents)

    Science.gov (United States)

    ... a dangerous situation. Before choosing any kind of animal for your family, learn as much as you can about your pet-to-be: Read pet guides explaining the various personalities, tendencies, and backgrounds of specific breeds in detail. ...

  12. Medical application of PET technology

    Energy Technology Data Exchange (ETDEWEB)

    Lim, Sang Moo; Choi, C. W.; An, S. H.; Woo, K. S.; Chung, W. S.; Yang, S. D.; Jun, G. S. and others

    1999-04-01

    We performed following studies using PET technology: 1. Clinical usefulness of [{sup 18}F]FDG whole body PET in malignant disease 2. Clinical usefulness of quantitative evaluation of F-18-FDG 3. Pilot study of C-11 methionine PET in brain tumor 4. PET study in patients with Parkinson's disease 5. A study on the clinical myocardial PET image. PET gives various metabolic information for the living human body, and is very important, new diagnostic modality. The PET study will give us the information of cancer patients such as early detection of cancer, staging, recurrence detection and characterization of cancer. The quantitative analysis using PET could be applied to evaluate the pathophysiology of various diseases and develop new drugs and develop new radiopharmaceuticals.

  13. PET/MR in oncology

    DEFF Research Database (Denmark)

    Balyasnikova, Svetlana; Löfgren, Johan; de Nijs, Robin

    2012-01-01

    After more than 20 years of research, a fully integrated PET/MR scanner was launched in 2010 enabling simultaneous acquisition of PET and MR imaging. Currently, no clinical indication for combined PET/MR has been established, however the expectations are high. In this paper we will discuss some...... of the challenges inherent in this new technology, but focus on potential applications for simultaneous PET/MR in the field of oncology. Methods and tracers for use with the PET technology will be familiar to most readers of this journal; thus this paper aims to provide a short and basic introduction to a number...... be applied together with PET increasing the amount of information about the tissues of interest. The potential clinical benefit of applying PET/MR in staging, radiotherapy planning and treatment evaluation in oncology, as well as the research perspectives for the use of PET/MR in the development of new...

  14. PET/MR in oncology

    DEFF Research Database (Denmark)

    Balyasnikova, Svetlana; Löfgren, Johan; de Nijs, Robin

    2012-01-01

    be applied together with PET increasing the amount of information about the tissues of interest. The potential clinical benefit of applying PET/MR in staging, radiotherapy planning and treatment evaluation in oncology, as well as the research perspectives for the use of PET/MR in the development of new......After more than 20 years of research, a fully integrated PET/MR scanner was launched in 2010 enabling simultaneous acquisition of PET and MR imaging. Currently, no clinical indication for combined PET/MR has been established, however the expectations are high. In this paper we will discuss some...... of the challenges inherent in this new technology, but focus on potential applications for simultaneous PET/MR in the field of oncology. Methods and tracers for use with the PET technology will be familiar to most readers of this journal; thus this paper aims to provide a short and basic introduction to a number...

  15. PET in neuro-oncology

    NARCIS (Netherlands)

    Roelcke, U; Leenders, K.L.

    This article reviews possible clinical applications of positron emission tomography (PET) in brain tumor patients. PET allows quantitative assessment of brain tumor pathophysiology and biochemistry. It therefore provides different information about tumors when compared to histological or

  16. PET imaging in multiple sclerosis

    NARCIS (Netherlands)

    Faria, Daniele de Paula; Copray, Sjef; Buchpiguel, Carlos; Dierckx, Rudi; de Vries, Erik

    Positron emission tomography (PET) is a non-invasive technique for quantitative imaging of biochemical and physiological processes in animals and humans. PET uses probes labeled with a radioactive isotope, called PET tracers, which can bind to or be converted by a specific biological target and thus

  17. Metabolic imaging using PET

    Energy Technology Data Exchange (ETDEWEB)

    Kudo, Takashi [University of Fukui, Biomedical Imaging Research Center, Eiheiji-cho, Fukui (Japan)

    2007-06-15

    There is growing evidence that myocardial metabolism plays a key role not only in ischaemic heart disease but also in a variety of diseases which involve myocardium globally, such as heart failure and diabetes mellitus. Understanding myocardial metabolism in such diseases helps to elucidate the pathophysiology and assists in making therapeutic decisions. As well as providing information on regional changes, PET can deliver quantitative information about both regional and global changes in metabolism. This capability of quantitative measurement is one of the major advantages of PET along with physiological positron tracers, especially relevant in evaluating diseases which involve the whole myocardium. This review discusses major PET tracers for metabolic imaging and their clinical applications and contributions to research regarding ischaemic heart disease and other diseases such as heart failure and diabetic heart disease. Future applications of positron metabolic tracers for the detection of vulnerable plaque are also highlighted briefly. (orig.)

  18. PET/MR in oncology

    DEFF Research Database (Denmark)

    Balyasnikova, Svetlana; Löfgren, Johan; de Nijs, Robin

    2012-01-01

    of the challenges inherent in this new technology, but focus on potential applications for simultaneous PET/MR in the field of oncology. Methods and tracers for use with the PET technology will be familiar to most readers of this journal; thus this paper aims to provide a short and basic introduction to a number...... be applied together with PET increasing the amount of information about the tissues of interest. The potential clinical benefit of applying PET/MR in staging, radiotherapy planning and treatment evaluation in oncology, as well as the research perspectives for the use of PET/MR in the development of new...

  19. Polyesteramides based on PET

    NARCIS (Netherlands)

    Bouma, K.

    1999-01-01

    Engineering plastics have good mechanical, thermal and electrical properties, and can be easily processed. Typical engineering plastics include polyamides (PA6,6, PA6, PA4,6) and polyesters (PBT, PET). Compared to polyesters of a similar structure, polyamides have a high glass transition (Tg) and

  20. PET's indsats under lup

    DEFF Research Database (Denmark)

    Hansen, Peer Henrik

    2006-01-01

    En undersøgelseskommission nedsat i 1999. Fem medlemmer skal undersøge PET's efterretningsvirksomhed i forhold til politiske partier, faglige konflikter og politisk ideologiske bevægelser i Danmark under den kolde krig. Kommissionens rapport forventes færdig næste år. Udgivelsesdato: 2. juli 2006...

  1. Birds Kept as Pets

    Science.gov (United States)

    ... Patients Infants and Young Children Publications & Materials Healthy Families and Flocks Pet Food Safety Trouble with Tiny Turtles Trouble with Tiny ... before purchase. Ask your veterinarian about the proper food, care, and enclosure or environment that is best for the bird you are ...

  2. PET and PET/CT in malignant melanoma; PET y PET/CT en melanoma maligno

    Energy Technology Data Exchange (ETDEWEB)

    Garcia O, J.R. [Nuclear Medicine and Molecular Imaging PET/CT, Centro Medico ABC, Mexico D.F. (Mexico)

    2007-07-01

    The advantages that it has the PET/CT are: 1. It diminishes mainly positive false lesions. It identifies physiologic accumulate places. 2. It diminishes in smaller grade false negative. Small injuries. Injuries with low grade concentration. Injure on intense activity areas. 3. Precise anatomical localization of accumulate places. 4. Reduction of the acquisition time. (Author)

  3. I Love Petting Zoos!

    Centers for Disease Control (CDC) Podcasts

    2010-03-23

    This Kidtastics podcast helps children learn about how to stay safe and healthy when visiting petting zoos and other animal exhibits.  Created: 3/23/2010 by Centers for Disease Control and Prevention (CDC).   Date Released: 3/23/2010.

  4. Reduced arbuscular mycorrhizal colonization in tomato ethylene mutants Reduzida formação de micorrízas arbusculares em tomateiros mutantes em etileno

    Directory of Open Access Journals (Sweden)

    Agustin Zsögön

    2008-01-01

    quais são super produtores e pouco sensíveis a etileno, respectivamente, tiveram a colonização intra-radicular por Glomus clarum inibida quando comparada com o controle Micro-Tom (MT. Não se observou alterações significativas na colonização fúngica nos mutantes afetando outras classes hormonais. Sob condição de baixo P, o nível de transcritos codificando uma quitinase básica de classe I (chi9 foi mais elevado em raízes micorrizadas dos mutantes epi e Nr, quando comparado com o controle MT. Em contraste, o nível de transcritos de uma b-1,3-glucanase ácida da classe III (TomPR-Q'a em raízes micorrizadas do mutante epi foi significativamente menor que em raízes micorrizadas de MT. A colonização de raízes no mutante epi foi acompanhada por várias alterações na morfologia fúngica, quando comparada com o controle MT. Os resultados sugerem que o etileno pode desempenhar um importante papel controlando o crescimento fúngico intra-radicular nas MAS.

  5. Talking with Children about Furry Classroom Pets.

    Science.gov (United States)

    Texas Child Care, 1994

    1994-01-01

    Notes that rodents and rabbits share many characteristics that make them suitable classroom pets and gives background information on rabbits, guinea pigs, hamsters, and gerbils. Offers advice on buying a classroom pet, the pet's home, feeding, helping the children handle the pet, and pet health and family planning. (TJQ)

  6. The pet connection: pets as a conduit for social capital?

    Science.gov (United States)

    Wood, Lisa; Giles-Corti, Billie; Bulsara, Max

    2005-09-01

    There is growing interest across a range of disciplines in the relationship between pets and health, with a range of therapeutic, physiological, psychological and psychosocial benefits now documented. While much of the literature has focused on the individual benefits of pet ownership, this study considered the potential health benefits that might accrue to the broader community, as encapsulated in the construct of social capital. A random survey of 339 adult residents from Perth, Western Australia were selected from three suburbs and interviewed by telephone. Pet ownership was found to be positively associated with some forms of social contact and interaction, and with perceptions of neighbourhood friendliness. After adjustment for demographic variables, pet owners scored higher on social capital and civic engagement scales. The results suggest that pet ownership provides potential opportunities for interactions between neighbours and that further research in this area is warranted. Social capital is another potential mechanism by which pets exert an influence on human health.

  7. Amadurecimento de manga 'Ubá' com etileno e carbureto de cálcio na pós-colheita Ripening of 'Ubá' mango using ethylene and calcium carbide

    Directory of Open Access Journals (Sweden)

    Danielle Fabíola Pereira da Silva

    2012-02-01

    Full Text Available Mangas 'Ubá' fisiologicamente maduras foram tratadas com etileno ou carbureto de cálcio (CaC2 visando à antecipação e à uniformização do amadurecimento. Frutos com massa média de 133,8±1,9g foram expostos às doses de 0, 20, 40, 80 e 160g de CaC2 m-3 de câmara ou 0, 50, 100, 200 e 400mL de etileno m-3 de câmara durante 24h, em câmaras a 18,1±0,7°C e 90±3% de UR. Após o tratamento, os frutos permaneceram sob as mesmas condições de temperatura e UR, e foram avaliados aos 0, 1, 3, 6, 9, 12 e 15 dias de armazenamento. O etileno e o CaC2 acentuaram a perda de massa das mangas. Nos frutos tratados com CaC2, o pico climatérico respiratório ocorreu aos 3, 6, 9, 9 e 12 dias de armazenamento para as doses 160, 80, 40, 20 e 0g/m³, respectivamente. Nos frutos tratados com etileno, este pico foi registrado aos 3, 3, 6, 6 e 12 dias de armazenamento para as doses 400, 200, 100, 50 e 0mL m-3, respectivamente. Todas as doses de CaC2 e de etileno aceleraram a perda de firmeza, o aumento do teor de sólidos solúveis e de carotenóides, a redução da acidez e a mudança de cor da casca e da polpa dos frutos. Por outro lado, esses produtos também acentuaram a perda de eletrólitos celulares e de ácido ascórbico. Nos frutos tratados com etileno, a queda da firmeza foi mais brusca em relação aos tratados com CaC2. No entanto, o extravasamento de solutos foi maior para frutos tratados com CaC2. O aumento no teor de sólidos solúveis foi proporcional ao aumento das doses de CaC2 e de etileno. Doses de 20g de CaC2 e 50mL de etileno por m³ de câmara foram suficientes para antecipar e uniformizar o amadurecimento de manga 'Ubá'.Physiologically mature 'Ubá' mangoes were treated with ethylene or calcium carbide (CaC2 aiming to accelerate and standardize fruit ripening. Fruits with mean weight of 133.8±1.9g were treated with concentrations of 0, 20, 40, 80 and 160g CaC2 chamber m-3 and 0, 50, 100, 200 and 400mL of ethylene/chamber m³, in

  8. Qualidade de kiwi armazenado em duas temperaturas sob atmosfera controlada e com eliminação de etileno Quality of kiwifruit stored under two temperatures and controlled atmosphere with ethylene absorption

    Directory of Open Access Journals (Sweden)

    Sérgio Miguel Mazaro

    2000-12-01

    Full Text Available Com objetivo de avaliar o efeito das temperaturas de armazenamento, concentrações de O2 e CO2 em câmaras de atmosfera controlada (AC e absorção e eliminação do etileno no armazenamento refrigerado (AR e em AC sobre as qualidades físico-químicas e organolépticas de kiwis, foi conduzido um experimento com as cultivares Bruno e Hayward. As temperaturas de armazenamento foram -0,5ºC e 0,5ºC e a umidade relativa do ar de 97%. As condições de AR avaliadas foram: sem absorção do etileno; com absorção do etileno através de filtros quí micos e eliminação de etileno através da ventilação da câmara. Em AC, os frutos foram armazenados em atmosfera contendo: 2kPa de O2 com 5 e 7kPa de CO2, com ou sem absorção do etileno através de filtros químicos. As avaliações foram realizadas após três meses de armazenamento para os frutos de ambas as cultivares conservadas em AR. Em AC, os frutos foram avaliados após três e oito meses de armazenamento para as cultivares Bruno e Hayward, respectivamente. Os resultados mostraram que o armazenamento a -0,5ºC propiciou, nas duas cultivares, melhor manutenção da firmeza de polpa e mais alta acidez titulável que o armazenamento a 0,5ºC, tanto na abertura das câmaras, como após cinco dias a 20ºC. Nas condições de atmosfera controlada com absorção do etileno, através de filtros químicos, os frutos apresentaram melhor qualidade durante o período de armazenamento, em comparação com os frutos sem absorção de etileno. Em AC, os frutos armazenados na condição de 2kPa de O2 com 7kPa de CO2 se mantiveram, de modo geral, com maior firmeza de polpa e acidez titulável do que aqueles armazenados em 2kPa de O2 com 5kPa de CO2. A ventilação da câmara no AR, para eliminação do etileno, não foi eficiente no controle da perda de qualidade dos frutos. A cv. Hayward apresentou maior potencial de armazenamento que a cv. Bruno.The experiment was carried out aiming to evaluate the

  9. THE PETS:Game Introduction of Pets in Two Languages

    Directory of Open Access Journals (Sweden)

    Wahyu Febriyanto

    2017-02-01

    Full Text Available Introducing environment is important for children. Included in this environment is the life of living beings such as humans, animals, and plants. The role of parents is needed in introducing the living creatures. One of the living creatures that endeared children are animals, especially the pets. Therefore made educational game The Pets. With the game "The Pets" is expected to help parents to teach the children in learning about pets based on place of living and food. In this paper describes how to design and create introducing pet game based on the type of food and its habitat in two different languages . "The Pets" has the Android platform with a minimum API Level 14 is created using the game engine Construct 2. Using two dimensional model and image with interesting coloring for children, and using the application CorelDraw X4. From results of the survey, "The Pets" can provide new knowledge and can assist children in learning about pets based on place of living and food. Children who previously could not mention animals vocabulary in English, after playing "The Pets" can name them into English.

  10. Breast PET/MR Imaging.

    Science.gov (United States)

    Melsaether, Amy; Moy, Linda

    2017-05-01

    Breast and whole-body PET/MR imaging is being used to detect local and metastatic disease and is being investigated for potential imaging biomarkers, which may eventually help personalize treatments and prognoses. This article provides an overview of breast and whole-body PET/MR exam techniques, summarizes PET and MR breast imaging for lesion detection, outlines investigations into multi-parametric breast PET/MR, looks at breast PET/MR in the setting of neo-adjuvant chemotherapy, and reviews the pros and cons of whole-body PET/MR in the setting of metastatic or suspected metastatic breast cancer. Copyright © 2016 Elsevier Inc. All rights reserved.

  11. Ingredients: where pet food starts.

    Science.gov (United States)

    Thompson, Angele

    2008-08-01

    Every clinician is asked "What should I feed my pet?" Understanding the ingredients in pet food is an important part of making the best recommendation. Pet food can be as simple as one ingredient or as complicated as containing more than 60 ingredients. Pet food and its ingredients are regulated by the Food and Drug Administration and state feed officials. Part of that regulation is the review and definition of ingredients. Existing ingredients change and new ingredients become available so the need for ingredient definitions grows. Ingredients for product formulations are chosen based on their nutrient content, digestibility, palatability, functionality, availability, and cost. As an example, a typical, nutritionally complete dry dog food with 42 ingredients is examined and the ingredients are discussed here. Safe, healthy pet food starts with safe ingredients sourced from well-monitored suppliers. The ultimate goal of both veterinarians and pet food manufacturers is the same--long healthy lives for dogs and cats.

  12. Inibição da ação do etileno e temperatura de armazenamento no padrão de amadurecimento de tomates Ethylene action inhibition and storage temperature on the tomatoes ripening patterns

    Directory of Open Access Journals (Sweden)

    Auri Brackmann

    2009-09-01

    Full Text Available O objetivo deste trabalho foi avaliar o efeito da inibição da ação do etileno sobre o amadurecimento e o desenvolvimento de dano causado pelo frio em tomates do tipo não longa vida da cultivar 'Monte Carlo'. O experimento foi conduzindo no delineamento inteiramente casualizado, em esquema fatorial (3x2, com quatro repetições. O Fator A foi composto por temperaturas de armazenamento (20°C, 10°C e 5°C, já o Fator B foi composto pela aplicação ou não de 1,0µL L-1 de 1-metilciclopropeno (1-MCP, um composto que bloqueia a ação do etileno. Depois de 14 dias de armazenamento, verificaram-se dois padrões distintos de amadurecimento dependentes da temperatura de armazenamento. A temperatura de 5°C levou ao desenvolvimento de dano pelo frio, o que resultou em elevada produção de etileno sem, contudo, levar a alterações significativas no amadurecimento dos frutos. Esses resultados indicam que sob essa temperatura os frutos perdem a sensibilidade ao etileno. No entanto, sob temperaturas acima do limite de dano, a aplicação de 1-MCP não apenas reduziu a síntese de etileno, mas também inibiu o amadurecimento, sendo a duração desse efeito maior a 10°C do que a 20°C. A qualidade de tomates não longa vida pode ser mantida por até 14 dias com o armazenamento a 10°C ou com a aplicação de 1-MCP a 20°C.This research aimed to evaluate the effect of inhibiting the ethylene action on the ripening and on the development of chilling injury in non-long life 'Monte Carlo' tomatoes. The experiment was a fatorial (3x2, with storage temperature (20°C, 10°C and 5°C and the treatment or not of 1.0µL L-1 of 1-methylcyclopropene (1-MCP, a compound that blocks the ethylene action. After 14 days of storage, two distinct patterns of ripening dependents on the storage temperature were observed. The storage under 5°C led the fruits to develop chilling injury (CI. Although CI-affected fruits showed higher ethylene production, they did not

  13. Integridade das membranas plasmática, nuclear e mitocondrial de espermatozóides ovinos criopreservados com etileno glicol Integrity of sperm plasm membrane, nucleus and mitochondria after freezing ram semen with ethylene glycol

    Directory of Open Access Journals (Sweden)

    Luciana Bignardi de Soares Brisola

    1999-09-01

    Full Text Available Este trabalho foi conduzido com o objetivo de avaliar o sêmen ovino criopreservado com etileno glicol em relação ao glicerol, quanto à motilidade progressiva e vigor e, especialmente, quanto à integridade das membranas plasmática, nuclear e mitocondrial. Foram utilizados ejaculados de sêmen provenientes de dois carneiros da raça Ile-de-France, com padrões mínimos de volume (0,5ml, turbilhonamento (2 de 0-5, motilidade progressiva (65%, vigor (3 de 0-5, aspecto (cremoso fino, 3x10(6 espermatozóides/mm3 e células normais (80%. Um total de 25 pools foi dividido em duas alíquotas, as quais foram, posteriormente, congeladas com etileno glicol a 0,5M ou glicerol a 0,72M em pellets. Os parâmetros utilizados, para avaliar o desempenho dos crioprotetores, foram a motilidade progressiva, vigor espermático e integridade do acrossomo e das membranas plasmáticas dos espermatozóides. A motilidade e vigor foram aferidos no sêmen fresco, resfriado, descongelado, mantido a 38°C por 5 horas de incubação (TTL- teste de termorresistência lento e à temperatura de 45°C por 30 minutos (TTR- teste de termorresistência rápido. Não houve diferença entre o etileno glicol e o glicerol para a avaliação da morfologia do acrossomo, motilidade progressiva e vigor. As células espermáticas criopreservadas com etileno glicol apresentaram maior integridade das membranas plasmática, nuclear e mitocondrial do espermatozóide. O etileno glicol é mais eficiente do que o glicerol para preservar a integridade das membranas espermáticas na congelação de sêmen ovino.The aim of the present experiment was to evaluate the effect of ethylene glycol, in relation to glycerol, as a cryoprotective agent for preserving ovine spermatic cells. The semen had to present a minimal quality to be used, regarding volume (0.5 ml, wave motion (score of 2, from 0 to 5, percentage of progressively motile spermatozoa (65%, rate of progressive motility (score of 3, from 0

  14. Armazenamento de pêssego 'Chimarrita' em atmosfera controlada e sob absorção de etileno Storage of 'Chimarrita' peach in controlled atmosphere and under ethylene absorption

    Directory of Open Access Journals (Sweden)

    Auri Brackmann

    2003-06-01

    Full Text Available Foram conduzidos dois experimentos com o objetivo de avaliar o efeito de duas formas de absorção de etileno e de condições de atmosfera controlada (AC sobre a qualidade do pêssego 'Chimarrita'. Os tratamentos do experimento 1 foram: testemunha com armazenamento refrigerado (AR; 1kPa de O2/3kPa de CO2; e 5kPa de O2/10kPa de CO2. No experimento 2, os mesmos tratamentos foram combinados com a absorção de etileno; absorção de etileno por filtro; e absorção de etileno por sache e sem absorção (testemunha. Tanto no experimento 1 como no experimento 2, os frutos foram armazenados na temperatura de -0,2ºC. As avaliações realizadas após 45 dias de armazenamento refrigerado + 2 dias em temperatura ambiente demonstraram que o uso de AC manteve os frutos com maior acidez titulável e reduziu a incidência de podridões e esporulação de fungos. Após os dois dias a 20ºC, os frutos armazenados em AC apresentaram-se mais firmes e com menor incidência de podridões e esporulação de patógenos. Os frutos mantidos na atmosfera de 5kPa de O2/10kPa de CO2 apresentaram maior incidência de lanosidade. No experimento 2, a absorção de etileno não foi eficiente na manutenção da qualidade do pêssego 'Chimarrita', mas após dois dias a 20ºC reduziu a incidência de podridões.Two experiments were carried out with the objective to evaluate the effects of two forms of ethylene absorption and controlled atmosphere (CA storage on the quality of 'Chimarrita' peaches. The treatments of the first experiment were: control (cold storage; 1kPa O2/3kPa CO2; e 5kPa O2/10kPa CO2. In the second experiment the same treatments were combined to ethylene absorption; either absorption using a filter or absorption using a sachet and no absorption at all. In both experiments, the fruits were stored at -0,2ºC for 45 days. At retrieval from storage, CA conditions maintained higher titratable acidity and reduced decay incidence and pathogen sporolution. After two

  15. Resina pet para recipientes

    OpenAIRE

    Montenegro, Ricardo Sá Peixoto; Monteiro Filha, Dulce Corrêa; Pan, Simon Shi Koo

    1996-01-01

    O mercado potencial de resina PET para recipientes é grande, com ampla expectativa de expansão. A nível mundial, esta ocorrendo um ciclo de expansão que deverá levar a uma sobrecapacidade, pressionando os preços para baixo. No Brasil, a escassez de resina PET tem retardado sua maior utilização em recipientes, notadamente de bebidas carbonatadas e em mercados em desenvolvimento, como o de óleo comestível e água mineral. Com a entrada em operação da fábrica da Nitrocarbono e da expansão da Rhod...

  16. PET studies in dementia

    Energy Technology Data Exchange (ETDEWEB)

    Herholz, K. [Neurologische Universitaetsklinik and Max-Planck-Inst. fuer neurologische Forschung, Koeln (Germany)

    2003-04-01

    Measurement of local cerebral glucose metabolism (lCMRGlc) by positron emission tomography (PET) and {sup 18}F-2-fluoro-2-deoxy-D-glucose (FDG) has become a standard technique during the past 20 years and is now available at many university hospitals in all highly developed countries. Many studies have documented a close relation between lCMRGlc and localized cognitive functions, such as language and visuoconstructive abilities. Alzheimer's disease (AD) is characterized by regional impairment of cerebral glucose metabolism in neocortical association areas (posterior cingulate, temporoparietal and frontal multimodal association cortex), whereas primary visual and sensorimotor cortex, basal ganglia, and cerebellum are relatively well preserved. In a multicenter study comprising 10 PET centers (Network for Efficiency and Standardization of Dementia Diagnosis, NEST-DD) that employed an automated voxel-based analysis of FDG PET images, the distinction between controls and AD patients was 93% sensitive and 93% specific, and even in very mild dementia (at Mini Mental Status Examination (MMSE) 24 or higher) sensitivity was still 84% at 93% specificity. Significantly abnormal metabolism in mild cognitive deficit (MCI) indicates a high risk to develop dementia within the next two years. Reduced neocortical glucose metabolism can probably be detected with FDG PET in AD on average one year before onset of subjective cognitive impairment. In addition to glucose metabolism, specific tracers for dopamine synthesis ({sup 18}F-F-DOPA) and for ({sup 11}C-MP4A) are of interest for differentiation among dementia subtypes. Cortical acetylcholine esterase activity (AChE) activity is significantly lower in patients with AD or with dementia with Lewy bodies (DLB) than in age-matched normal controls. In LBD there is also impairment of dopamine synthesis, similar to Parkinson disease. (author) 115 refs.

  17. Pet overpopulation: An economic analysis

    OpenAIRE

    Coate, Stephen; Knight, Brian

    2009-01-01

    This paper considers the problem of pet overpopulation. It develops a tractable dynamic model whose positive predictions square well with key features of the current U.S. market for pets. The model is used to understand, from a welfare economic perspective, the sense in which there is \\overpopulation" of pets and the underlying causes of the problem. The paper also employs the model to consider what policies might be implemented to deal with the problem. A calibrated example is developed to i...

  18. Client services for geriatric pets.

    Science.gov (United States)

    Hancock, G; Yates, J

    1989-01-01

    Some veterinarians have been reluctant to discuss the prospect of the death of a pet because of a sense of discomfort and a lack of understanding about how to respond to the client's grief reaction. It is essential to take the time for this important communication and help clients deal with fears about the process, any feelings of guilt and helplessness, and judgments about the medical aspects of a case. Clients must be encouraged to express grief over the loss of a pet, particularly a geriatric pet that has lived with them many years and to which they are deeply bonded. Veterinarians need to counsel clients about obtaining additional pets or another pet. The phrase "replacement pet" must be stricken from the veterinarian's vocabulary. One does not "replace" a deceased spouse, mother, father, or child. It is possible to have another child or find another spouse, but it is not possible to replace a person. Neither can a pet be "replaced," because each pet is a unique living being. It is disrespectful to the memory of deceased pets to belittle their uniqueness by suggesting that they can be replaced. Instead, the veterinarian has the capability and responsibility to help pet owners maintain fond and happy memories of an irreplacable pet, while finding room in their hearts for another new pet to create happiness for the future. Once the grief is resolved, clients will be thankful for having had the privilege of sharing their life with an animal and experiencing the joy of the bond between two unique individuals.

  19. PET and Recycling

    Directory of Open Access Journals (Sweden)

    Funda Sevencan

    2007-08-01

    Full Text Available This review aims to clarify the need of decreasing the environmental effects caused by human and draw attention to the increasing environmental effects of plastics wastes. Plastics consist of organic molecules with high density molecules or polymers. Main resources of plastics are the residue of oil rafineries. Several advantages of plastics, have increased the usage continuously. Polyethylene Terephthalate (PET is the most commonly used plastics. PET is used to protect food, drinking water, fruit juice, alcoholic beverage, and food packing films. By the increasing interest on the environmental effects of plastic wastes, concerns on the recyclable packing materials also grew up. Also the daily use of recyclable containers consisting PET have increased. There are five steps for recycling of plastics. These steps are; using large amounts of plastics, collecting them in a big center, classifying and sorting the plastics, reproducing the polymers and obtaining new products with melted plastics. Providing a healthy recycling of plastics, the consumers should have knowledge and responsibility. The consumer should know what he/she has to do before putting the plastics in the recycling containers. Recycling containers and bags should be placed near the sources of plastic wastes. Consequently, the plastic wastes and environmental problems they cause will be on the agenda in future. [TAF Prev Med Bull. 2007; 6(4: 307-312

  20. PET and Recycling

    Directory of Open Access Journals (Sweden)

    Funda Sevencan

    2007-08-01

    Full Text Available This review aims to clarify the need of decreasing the environmental effects caused by human and draw attention to the increasing environmental effects of plastics wastes. Plastics consist of organic molecules with high density molecules or polymers. Main resources of plastics are the residue of oil rafineries. Several advantages of plastics, have increased the usage continuously. Polyethylene Terephthalate (PET is the most commonly used plastics. PET is used to protect food, drinking water, fruit juice, alcoholic beverage, and food packing films. By the increasing interest on the environmental effects of plastic wastes, concerns on the recyclable packing materials also grew up. Also the daily use of recyclable containers consisting PET have increased. There are five steps for recycling of plastics. These steps are; using large amounts of plastics, collecting them in a big center, classifying and sorting the plastics, reproducing the polymers and obtaining new products with melted plastics. Providing a healthy recycling of plastics, the consumers should have knowledge and responsibility. The consumer should know what he/she has to do before putting the plastics in the recycling containers. Recycling containers and bags should be placed near the sources of plastic wastes. Consequently, the plastic wastes and environmental problems they cause will be on the agenda in future. [TAF Prev Med Bull 2007; 6(4.000: 307-312

  1. Respiratory gating in cardiac PET

    DEFF Research Database (Denmark)

    Lassen, Martin Lyngby; Rasmussen, Thomas; Christensen, Thomas E

    2017-01-01

    BACKGROUND: Respiratory motion due to breathing during cardiac positron emission tomography (PET) results in spatial blurring and erroneous tracer quantification. Respiratory gating might represent a solution by dividing the PET coincidence dataset into smaller respiratory phase subsets. The aim...... stress (82)RB-PET. Respiratory rates and depths were measured by a respiratory gating system in addition to registering actual respiratory rates. Patients undergoing adenosine stress showed a decrease in measured respiratory rate from initial to later scan phase measurements [12.4 (±5.7) vs 5.6 (±4.......7) min(-1), P PET...

  2. PET and PET/CT - clinical value in lung cancer; PET und PET/CT - Stellenwert beim Lungenkarzinom

    Energy Technology Data Exchange (ETDEWEB)

    Steinert, H.C. [Klinik und Poliklinik fuer Nukearmedizin, Dept. Medizinische Radiologie, Univ. Zuerich (Switzerland)

    2004-12-01

    Preoperative staging of lung cancer is essential for prognosis and management. The aim of this overview is to present the synergistic effects of FDG-PET and CT. For planning surgery and planning radiation treatment the precise definition of the tumor extend is essential. Integrated PET/CT scanning enables the exact localization of tumor infiltration into surrounding tissue and of small metastases. In this overview the applications of PET and PET/CT in non-small-cell lung cancer, small-cell lung cancer and malignant pleural mesothelioma are presented. (orig.)

  3. Cost-effectiveness of PET and PET/Computed Tomography

    DEFF Research Database (Denmark)

    Gerke, Oke; Hermansson, Ronnie; Hess, Søren

    2015-01-01

    measure by means of incremental cost-effectiveness ratios when considering the replacement of the standard regimen by a new diagnostic procedure. This article discusses economic assessments of PET and PET/computed tomography reported until mid-July 2014. Forty-seven studies on cancer and noncancer...

  4. Innovations in PET/CT

    DEFF Research Database (Denmark)

    Levin Klausen, T; Høgild Keller, S; Vinter Olesen, O

    2012-01-01

    There has been a longstanding interest in positron emission tomography (PET) in combination with computed tomography (CT). Mostly because of the lack of structural information in PET which makes it difficult to assess the precise location of tissue with metabolic uptake, whereas CT can provide im...

  5. Welfare assessment in pet rabbits

    NARCIS (Netherlands)

    Schepers, F.; Koene, P.; Beerda, B.

    2009-01-01

    One million pet rabbits are kept in The Netherlands, but there are no data available on their behaviour and welfare. This study seeks to assess the welfare of pet rabbits in Dutch households and is a first step in the development of a welfare assessment system. In an internet survey, housing

  6. Business Plan of Precious Pets

    OpenAIRE

    Gupta, Nitesh

    2009-01-01

    Precious Pets is a one stop shop for all the dog lovers and pet owners in India. It not only breeds and sells pedigree dogs in its facility but also provides all the related products and services under the same roof as well.

  7. Pet Ownership: A Research Note.

    Science.gov (United States)

    Lawton, M. Powell; And Others

    1984-01-01

    Data from a 1968 national sample of older people (N=3,996) indicated that pet ownership was more frequent in owner-occupied residences in smaller communities where other family, including children were present. No association was found between pet ownership and psychological well-being or health. (Author)

  8. Neurotransmission imaging by PET

    Energy Technology Data Exchange (ETDEWEB)

    Takano, Akihiro; Suhara, Tetsuya [National Inst. of Radiological Sciences, Chiba (Japan)

    2001-08-01

    PET studies on neurotransmission in psychological disorders to evaluate abnormal neurotransmission and therapeutic effects are thoroughly reviewed by type of major neurotransmitters. Studies on dopaminergic neurotransmission have focused on the function of dopamine D{sub 2} receptors, receptor subtypes, such as the D{sub 1} receptor, and ligands, such as transporters. PET studies of dopamine D{sub 2} receptor, which began in the early 1980s, have predominantly been performed in schizophrenia, and most have failed to detect any statistically significant differences between schizophrenia patients and controls. The studies in the early 1980s were performed by using [{sup 11}C]N-methyl-spiperone (NMSP) and [{sup 11}C]raclopride, ligands for striatal dopamine D{sub 2} receptors. [{sup 11}C]FLB457, which has much higher affinity for D{sub 2} receptors than raclopride, began to be used in the 1990s. Dopamine D{sub 2} occupancy after drug ingestion has also been investigated to clarify the mechanisms and effects of antipsychotic drugs, and there have also been studies on the effect of aging and personality traits on dopamine D{sub 2} receptor levels in healthy subjects. In studies on dopamine receptor subtypes other than D{sub 2}, dopamine D{sub 1} receptors have been studied in connection with assessments of cognitive functions. Most studies on dopamine transporters have been related to drug dependence. Serotonin 5-HT{sub 2A} receptors have been studied with [{sup 11}C]NMSP in schizophrenia patients, while studies of another serotonin receptor subtype, 5-HT{sub 1A} receptors, have been mainly conducted in patients with depression. [{sup 11}C]NMSP PET showed no difference between schizophrenia patients who had not undergone phamacotherapy and normal subjects. Because serotonin selective reuptake inhibitors (SSRIs) affect serotonin transporters, and abnormalities in serotonin transporters detected in mood disorders, PET ligands for serotonin transporters have increasingly

  9. [Behavior of pet animals].

    Science.gov (United States)

    Birmelin, I

    1990-06-01

    Severe mistakes in pet keeping are often the result of ignorance. Many animals suffer from the care of their owners. Industry provides food in the proper composition, but the importance of the cage's interior, its size and the number of animals of the same species kept in it is often neglected. The key to a better understanding of pets is the knowledge of the ecological environment of their species. Fish, amphibia and reptiles are capable of simple acts of learning, but their potential of adaptation to their environment is determined mainly genetically, which can be observed best during the phase of their youth. Most members of these animal groups are born with a perfect behaviour program. Thus aquaria and terraria should as far as possible correspond to the needs and requirements of the species in question to its ecological niche. An aquarium should be a model of the animals' biotope. The effect of the conditions under which a pet is kept on its wellbeing is discussed in detail for the budgerigar and the guinea pig. Experiments with budgerigars showing that too small cages and the missing company of animals of the same species lead to abnormal behaviour are described. Guinea pigs live in packs. The fact how important the group and its social organization is for the individual guinea pig is documented by experimentally verified data. Furthermore the effect of the guinea pig's ontogeny under experimental conditions on the structure of a pack is discussed. Already small changes in the size of the cage or in its interior encourage the guinea pig's exploration behaviour and its mobility.

  10. Simultaneous PET and MR imaging

    Energy Technology Data Exchange (ETDEWEB)

    Yiping Shao; Cherry, Simon R.; Meadors, Ken; Siegel, Stefan; Silverman, Robert W. [Crump Institute for Biological Imaging, Department of Molecular and Medical Pharmacology, 10833 Le Conte Avenue, UCLA School of Medicine, Los Angeles, CA 90095 (United States); Farahani, Keyvan [Department of Radiological Sciences, 10833 Le Conte Avenue, UCLA School of Medicine, Los Angeles, CA 90095 (United States); Marsden, Paul K. [Guy' s and St Thomas' Clinical PET Centre, Division of Radiological Sciences, UMDS, London (United Kingdom)

    1997-10-01

    We have developed a prototype PET detector which is compatible with a clinical MRI system to provide simultaneous PET and MR imaging. This single-slice PET system consists of 48 2x2x10mm{sup 3} LSO crystals in a 38 mm diameter ring configuration that can be placed inside the receiver coil of the MRI system, coupled to three multi-channel photomultipliers housed outside the main magnetic field via 4 m long and 2 mm diameter optical fibres. The PET system exhibits 2 mm spatial resolution, 41% energy resolution at 511 keV and 20 ns timing resolution. Simultaneous PET and MR phantom images were successfully acquired. (author)

  11. Supplements for exotic pets.

    Science.gov (United States)

    Mejia-Fava, Johanna; Colitz, Carmen M H

    2014-09-01

    The use of supplements has become commonplace in an effort to complement traditional therapy and as part of long-term preventive health plans. This article discusses historical and present uses of antioxidants, vitamins, and herbs. By complementing traditional medicine with holistic and alternative nutrition and supplements, the overall health and wellness of exotic pets can be enhanced and balanced. Further research is needed for understanding the strengths and uses of supplements in exotic species. Going back to the animals' origin and roots bring clinicians closer to nature and its healing powers. Copyright © 2014 Elsevier Inc. All rights reserved.

  12. Análisis microbiológico de plantas medicinales con óxido de etileno Microbiologic analysis of medicinal plants using ethylene oxide

    Directory of Open Access Journals (Sweden)

    Mausy Lorena Torres Rojas

    2007-08-01

    Full Text Available La utilización de plantas curativas constituye una de las terapias médicas más antiguas y extendidas que se remonta a los tiempos prehistóricos (Wust, 2003. Cada cultura ha desarrollado sus tradiciones de medicina popular, con remedios y ritos que utilizan plantas locales. La Organización Mundial de la Salud, mediante varios comunicados ha expresado su posición con respecto a la necesidad de revalorar la utilización de las plantas medicinales dentro del ámbito sanitario, teniendo en cuenta que el 80 % de la población mundial depende de estas en lo referente a la atención primaria de salud (Alonso, 1998. Frente a esta necesidad y a la preocupación que genera ofrecer productos de alta calidad, la investigación realizada permitió evaluar algunas de las materias primas, como: Boldo (Peumus boldus, Caléndula (Calendula officinalis, Sen (Casia angustifolia Vahl, Fucus (Fucus vesiculosas L y Spirulina (Spirulina maxima, que son importantes por la gran oferta que estas tienen en el mercado. El objetivo de este estudio fue evaluar la calidad microbiológica y establecer si el proceso de esterilización con óxido de etileno tenía un efecto eficaz sobre la materia prima, propuesta a evaluar. Se realizó el recuento de microorganismos mesófilos aerobios, hongos, levaduras y pruebas de ausencia/presencia para microorganismos patógenos como: Escherichia coli, Pseudomonas aeruginosa, Salmonella s.p, Clostridium perfringes y Staphylococcus aureus. Estas pruebas se realizaron con la utilización de medios de cultivo específicos: TSN, EMB, CETRIMIDE, XLD, B.P, OGY (hongos y levaduras y Plate Count (mesófilos aerobios. Los resultados obtenidos a partir de las muestras analizadas permitieron obtener datos significativos relacionados con la ausencia/presencia de microorganismos patógenos antes y después del proceso de esterilización, así como el recuento de mesófilos, hongos y levaduras. En las muestras analizadas antes de la esterilizaci

  13. Non FDG PET

    Energy Technology Data Exchange (ETDEWEB)

    Nanni, C., E-mail: cristina.nanni@aosp.bo.i [Nuclear Medicine Unit, Policlinico S.Orsola, University of Bologna, Bologna (Italy); Fantini, L.; Nicolini, S.; Fanti, S. [Nuclear Medicine Unit, Policlinico S.Orsola, University of Bologna, Bologna (Italy)

    2010-07-15

    2- [{sup 18}F]-fluoro-2-deoxy-D-glucose (FDG) is the radiopharmaceutical most frequently used for clinical positron emission tomography (PET). However, FDG cannot be used for many oncological, cardiological, or neurological conditions, either because the abnormal tissue does not concentrate it, or because the tissues under investigation demonstrate high physiological glucose uptake. Consequently, alternative PET tracers have been produced and introduced into clinical practice. The most important compounds in routine practice are {sup 11}C-choline and {sup 18}F-choline, mainly for the evaluation of prostate cancer; {sup 1}C-methionine for brain tumours; {sup 118}F-DOPA ({sup 18}F- deoxiphenilalanine) for neuroendocrine tumours and movement disorders; {sup 68}Ga-DOTANOC (tetraazacyclododecanetetraacetic acid-[1-Nal3]-octreotide) and other somatostatin analogues for neuroendocrine tumours; 11C-acetate for prostate cancer and hepatic masses and 18F-FLT (3'-deoxy-3'-fluorothymidine) for a number of malignant tumours. Another impetus for the development of new tracers is to enable the investigation of biological processes in tumours other than glucose metabolism. This is especially important in the field of response assessment, where there are new agents that are targeted more specifically at angiogenesis, hypoxia, apoptosis and other processes.

  14. FDG PET imaging dementia

    Energy Technology Data Exchange (ETDEWEB)

    Ahn, Byeong Cheol [Kyungpook National University Medical School and Kyungpook National University Hospital, Daegu (Korea, Republic of)

    2007-04-15

    Dementia is a major burden for many countries including South Korea, where life expectancy is continuously growing and the proportion of aged people is rapidly growing. Neurodegenerative disorders, such as, Alzheimer disease, dementia with Lewy bodies, frontotemporal dementia. Parkinson disease, progressive supranuclear palsy, corticobasal degeneration, Huntington disease, can cause dementia, and cerebrovascular disease also can cause dementia. Depression or hypothyroidism also can cause cognitive deficits, but they are reversible by management of underlying cause unlike the forementioned dementias. Therefore these are called pseudodementia. We are entering an era of dementia care that will be based upon the identification of potentially modifiable risk factors and early disease markers, and the application of new drugs postpone progression of dementias or target specific proteins that cause dementia. Efficient pharmacologic treatment of dementia needs not only to distinguish underlying causes of dementia but also to be installed as soon as possible. Therefore, differential diagnosis and early diagnosis of dementia are utmost importance. F-18 FDG PET is useful for clarifying dementing diseases and is also useful for early detection of the disease. Purpose of this article is to review the current value of FDG PET for dementing diseases including differential diagnosis of dementia and prediction of evolving dementia.

  15. Pet food recalls and pet food contaminants in small animals.

    Science.gov (United States)

    Bischoff, Karyn; Rumbeiha, Wilson K

    2012-03-01

    Most pet foods are safe, but incidents of chemical contamination occur and lead to illness and recalls. There were 11 major pet food recalls in the United States between 1996 and 2010 that were due to chemical contaminants or misformulations: 3 aflatoxin, 3 excess vitamin D3, 1 excess methionine, 3 inadequate thiamine, and 1 adulteration with melamine and related compounds and an additional 2 warnings concerning a Fanconilike renal syndrome in dogs after ingesting large amounts of chicken jerky treat products. This article describes clinical findings and treatment of animals exposed to the most common pet food contaminants.

  16. Compatibilidades e incompatibilidades entre radiação gama e óxido de etileno como métodos sucessivos de esterilização Compatibilidades e incompatibilidades entre rayos gama y óxido de etileno como métodos sucesivos de esterilización Compatibilities and incompatibilities between gamma rays and ethylene oxide as consecutive sterilization methods

    Directory of Open Access Journals (Sweden)

    Rafael Queiroz de Souza

    2010-12-01

    Full Text Available A dúvida sobre a questão da re-esterilização de artigos confeccionados com cloreto de polivinila (PVC, esterilizados em radiação gama (RG e posteriormente em óxido de etileno (EO persiste até os dias atuais. Por meio da revisão integrativa da literatura, este artigo analisou estudos que evidenciaram compatibilidades e incompatibilidades entre os processos de esterilização com RG e EO quando utilizados como métodos sucessivos de esterilização. Foram analisados 7 estudos. Constatou-se que há influência multifatorial na segurança do procedimento e que o método analítico da cromatografia empregado na maioria dos estudos produziu resultados controversos. Esse fato indica a necessidade da realização de novos estudos sobre o assunto, utilizando-se métodos analíticos mais sensíveis do que a cromatografia gasosa, como o teste de reatividade biológica em culturas celulares, que poderá dirimir em nosso meio a crônica dúvida da compatibilidade ou incompatibilidade de se esterilizar em EO materiais previamente gamairradiados.La duda sobre la cuestión de la reesterilización de artículos confeccionados con policloruro de vinilo (PVC esterilizados con Rayos Gamma (RG y posteriormente en óxido de etileno (EO persiste hasta la actualidad. A través de la revisión integradora de la literatura, este artículo analizó estudios que evidenciaron compatibilidades e incompatibilidades entre los procesos de esterilización con RG y EO, cuando se utilizan en forma sucesiva. Fueron analizados 7 estudios. Se constató que hay influencia multifactorial en la seguridad del procedimiento y que el método analítico de cromatografía empleado en la mayoría de los estudios generó resultados controversiales. Este hecho indica la necesidad de realizar nuevos estudios sobre el asunto, utilizando métodos analíticos más sensibles que la cromatografía gaseosa, tales como el test de reactividad biológica en cultivos celulares para dirimir en

  17. Older Latinos, pets, and health.

    Science.gov (United States)

    Johnson, Rebecca A; Meadows, Richard L

    2002-10-01

    The majority of thefindings regarding pet ownership, interaction, and the human-animal bond have involved only Caucasians or have included other ethnic group members only incidentally. The extent to which older adultsfrom other ethnic groups may benefitfrom pet ownership and interaction is unclear. If the benefits of human-animal interaction are to be used effectively in promoting health and preventing illness, it is necessary to identify the "boundaries" of effectiveness for this interaction across various populations. The present study is an initial effort at describing one ethnic minority group, Latino pet owners, the extent of their relationships with their pet, and the extent to which these relationships may be beneficial in facilitating health. Twenty-four Latinos over age 50 were studied and are described in terms of their demographic characteristics, relationships with their pets, health, and exercise practices. The findings suggest that the participants were very devoted to their pets, had been involved with pets since childhood, and viewed themselves as healthy.

  18. Understanding regulations affecting pet foods.

    Science.gov (United States)

    Dzanis, David A

    2008-08-01

    In the United States, pet foods are subject to regulation at both the federal and the state levels. The US Food and Drug Administration has jurisdiction over all animal feeds (including pet foods, treats, chews, supplements, and ingredients) in interstate commerce, which includes imported products. Many states adopt and enforce at least in part the Association of American Feed Control Officials Model Bill and Model Regulations for Pet Food and Specialty Pet Food. Thus, all pet foods in multi-state distribution are subject to a host of labeling requirements covering aspects such as product names, ingredient lists, nutrient content guarantees, and nutritional adequacy statements. Ingredients must be GRAS (generally recognized as safe) substances, approved food additives, or defined by Association of American Feed Control Officials for their intended use. Pet food labels may not bear claims that are false or misleading or that state or imply use for the treatment or prevention of disease. Pet foods that are found to be adulterated or misbranded may be subject to seizure or other enforcement actions.

  19. Pet ownership and physical health.

    Science.gov (United States)

    Matchock, Robert L

    2015-09-01

    Pet ownership and brief human-animal interactions can serve as a form of social support and convey a host of beneficial psychological and physiological health benefits. This article critically examines recent relevant literature on the pet-health connection. Cross-sectional studies indicate correlations between pet ownership and numerous aspects of positive health outcomes, including improvements on cardiovascular measures and decreases in loneliness. Quasi-experimental studies and better controlled experimental studies corroborate these associations and suggest that owning and/or interacting with a pet may be causally related to some positive health outcomes. The value of pet ownership and animal-assisted therapy (AAT), as a nonpharmacological treatment modality, augmentation to traditional treatment, and healthy preventive behavior (in the case of pet ownership), is starting to be realized. However, more investigations that employ randomized controlled trials with larger sample sizes and investigations that more closely examine the underlying mechanism of the pet-health effect, such as oxytocin, are needed.

  20. Efeito do CO2 e etileno no período de dormência de minitubérculos de batata cv. Macaca Effect of CO2 and ethylene on the dormancy period of potato cv. Macaca minitubers

    Directory of Open Access Journals (Sweden)

    Dilson Antônio Bisognin

    2007-06-01

    Full Text Available Avaliou-se o efeito do CO2 e etileno no período de dormência de minitubérculos de batata da cultivar Macaca produzidos em telado durante duas safras. Imediatamente após a colheita, os minitubérculos foram submetidos aos tratamentos de abafamento com etileno (1000 mL L-1 por 72 h; CO2 (20% por 72 h; carbureto de cálcio (200 g m-3 por 72 h; e 1-metilciclopropeno (1-MCP (1mL L-1 por 24 h (apenas na safrinha; e imersão em solução de ethephon (840 mg L-1 por 5 s. A testemunha não recebeu nenhum tratamento. O delineamento experimental foi um fatorial (safras x tratamentos no inteiramente casualizado, com quatro repetições de 15 minitubérculos. Em intervalos semanais foram avaliadas a respiração e a produção de etileno. A cada 15 dias avaliou-se o número de brotos e a percentagem de tubérculos brotados, calculando-se a área abaixo da curva de progressão. Os minitubérculos produzidos durante a safra, comparados com os da safrinha, apresentaram menor período de dormência e aumentaram a taxa respiratória durante o período de armazenamento, claramente relacionados com a brotação dos minitubérculos. O CO2 e etileno não promoveram o encurtamento, enquanto que o 1-MCP prolongou o período de dormência de minitubérculos de batata cv. Macaca.The effect of CO2 and ethylene treatments were evaluated on the dormancy period of 'Macaca' minitubers produced in greenhouse during two growing seasons. Minitubers were treated soon after harvesting. The treatments were suffocation with ethylene (1000 mL L-1 during 72 h; CO2 (20 % during 72 h; calcium carburet (200 g m-3 during 72 h; and 1-methylcyclopropene (1-MCP (1 mL L-1 during 24 h (only for second season; and immersion with 2-cloroetil fosfonic acid (840 mg L-1 during 5 s. Control minitubers did not receive any treatment. The experiment was a factorial (seasons x treatments in a randomized design, with four replications of 15 minitubers. Respiration and ethylene production were

  1. Estudio de propiedades térmicas y mecánicas en espumas de mezclas poliméricas entre copolímero de etileno-acetato de vinilo (EAV y caucho natural (CN

    Directory of Open Access Journals (Sweden)

    Daniel Alberto Morales Rivera

    2006-01-01

    Full Text Available Se estudiaron algunas propiedades de espumas poliméricas, preparadas con mezclas de copolímeros de etileno-acetato de vinilo (EAV y caucho natural (CN: comportamiento térmico, por análisis térmico diferencial (DSC, y análisis termogravimétrico (TGA, resistencia a la tracción, compresión set y contenido de gel. Se establecieron relaciones entre la composición de las mezclas y las propiedades medidas en función de la reticulación y el espumado, teniendo en cuenta estudios previos realizados en espumas poliolefínicas con densidades similares.

  2. Estudo de equilíbrio de fases para sistemas aquosos bifásicos compostos por poli (etileno glicol) 6000, sulfato de cobre ou sulfato de zinco e água, em função da temperatura

    OpenAIRE

    Carvalho, Marcelo Mendes de

    2007-01-01

    Neste trabalho foram determinados diagramas de equilíbrio para sistemas aquosos bifásicos compostos por poli (etileno glicol) (PEG) 6000 g.mol-1, sulfato de cobre ou sulfato de zinco e água, nas temperaturas de (5, 10, 35 e 45) ºC. Cada diagrama foi composto por cinco linhas de amarração. Na quantificação dos componentes das fases, os teores de sal e água foram obtidos, respectivamente, por medidas de absorção atômica e liofilização. O conteúdo de PEG foi calculado por diferença. Os efeitos d...

  3. Influência da estrutura de diferentes copolímeros de etileno e a-olefinas na funcionalização com anidrido maleico Influence of structure of ethylene a-olefins copolymers in functionalization with maleic anhydride

    Directory of Open Access Journals (Sweden)

    Carlota H. F. Maurano

    1998-01-01

    Full Text Available A funcionalização de copolímeros de etileno e a-olefinas com anidrido maleico (AM foi realizada em solução de xileno com peróxido de dibenzoíla (DBP como iniciador. Foi estudado o efeito das diferentes estruturas dos copolímeros, como número e comprimento de ramificação, na incorporação do AM. A funcionalização também foi realizada em estado fundido utilizando-se um misturador Rheomix 600 e uma extrusora Rheocord 9000 da Haake. A funcionalidade foi determinada por titulometria de neutralização e os produtos foram caracterizados por espectroscopia na região do infravermelho (FT-IR e por cromatografia de permeação em gel (GPC. A funcionalidade dos copolímeros de etileno com 1-hexeno aumentou com o aumento do teor de comonômero e dos copolímeros com 1-octeno e 1-deceno aumentou com o aumento do teor de a-olefina até um máximo, decrescendo e mantendo-se constante.Chemical modification of ethylene a-olefins copolymers with maleic anhydride was studied by radical reaction in solution, melt mixing and extrusion. The effect of copolymer structure, as the amount and length of the branches, was evaluated on the MA incorporation. The reactions were also achieved in Rheomix 600 (Haake mixer and Rheocord 9000 (Haake extruder. Functionalization was determinated by titration and modified ethylene a-olefins copolymers were characterized by Infrared Spectroscopy and Gel Permeation Chromatography. The maleic anhydride incorporation in the ethylene-hexene copolymers increases with the amount of a-olefin. Functionalization of ethylene-octene and ethylene-decene comonomers increases with increasing peroxide concentration until a maximum and then decreases up to a constant value.

  4. Emissão de etileno e de CO2 em mamão 'Sunrise Solo' e 'Golden' Emission of ethilene and CO2 in 'Sunrise Solo' and 'Golden' papaya

    Directory of Open Access Journals (Sweden)

    Marcos José de Oliveira Fonseca

    2006-08-01

    Full Text Available Frutos de mamoeiro 'Sunrise Solo' e 'Golden' foram armazenados a 10º C e a 25º C e monitorados diariamente quanto às emissões de CO2 e de C2H4, observando-se a evolução do índice de cor de casca. A não-alteração do índice de cor de casca, ao longo dos 20 dias de conservação a 10º C, refletiu a influência da refrigeração na retenção do metabolismo dos mamões. Houve dois incrementos da respiração e da emissão de etileno, no quarto dia e entre o oitavo e o nono dia, nos frutos armazenados a 25º C. A temperatura de 10º C deteve a respiração climatérica do mamão e a emissão de etileno, comprovando que o seu metabolismo se reduz, permitindo que os frutos apresentem aspecto imaturo após 20 dias de armazenamento.Papaya fruits of Sunrise Solo and Golden cultivars were stored at 10ºC and 25ºC. They were daily evaluated on C2H4 and CO2 production rates, by observing the peel color index increasing. The non increasing of the peel color index, during the 20 days of stored, was influenced by the appropriate refrigeration temperature whose inhibit papayas metabolism. It was noticed in the fourth and between the eighth and ninth day an increasing on respiration and ethylene rates, in the fruits stored at 25ºC. The refrigeration decreased the respiration rate and papayas ethylene production, showing a metabolism reduction allowing fruits to present unripe appearance, even after 20 days of storage.

  5. Salmonella: Dry Pet Foods and Pet Treats (FAQ)

    Science.gov (United States)

    ... will have a decreased appetite, fever and abdominal pain. However, not all pets carrying Salmonella will appear sick. Apparently well but infected animals can be carriers and may infect other animals ...

  6. PET/TAC in Oncology; PET/TAC en Oncologia

    Energy Technology Data Exchange (ETDEWEB)

    Jimenez V, A.M. [Especialista en Medicina Nuclear, Profa. Depto. Radiologia de la Facultad de Medicina, Universidad Complutense de Madrid, Madrid (Spain)

    2007-07-01

    From this presentation of PET-TAC in oncology the following advantages on the conventional PET are obtained: 1. More short study and stadium in one session. 2. It adds the information of both techniques. 3. Better localization of leisure: affected organ, stadium change (neck, mediastinum, abdomen). 4. Reduction of false positive (muscle, brown fat, atelectasis, pneumonias, intestine, urinary vials, etc.). 5. Reduction of negative false. 6. Reduction of not conclusive. 7. More understandable for other specialists. 8. Biopsies guide. 9. Planning radiotherapy.

  7. PET/MR sammenlignet med PET/CT: fordeler og ulemper

    OpenAIRE

    Haugsrud, Jane Marion; Mikalsen, Linn Bergh; Olsen, Celine Hestvik

    2014-01-01

    NORSK: Problemstilling: Hva er dokumentert av fordeler og ulemper ved PET/MR sammenlignet med PET/CT, og kan PET/MR benyttes ved kreftdiagnostikk av barn og unge? Hensikt: Er på sammenligne PET/MR med PET/CT, og om PET/MR kan brukes på barn ved kreftutredning. Metode: Kvalitativt litteraturstudie med analyse av artikler. Resultat: De tekniske utfordringene ved PET/MR er hovedsakelig attenuasjonskorreksjon og kompatibilitet mellom komponentene. En av hovedgrunnene til at PET/MR kan væ...

  8. Co-pyrolysis of waste propylene and gas oil from Campos Basin: a case study; Tecnologia de co-pirolise de polipropileno pos-consumo com gasoleo da Bacia de Campos: um estudo de caso

    Energy Technology Data Exchange (ETDEWEB)

    Assumpcao, Luiz Carlos F.N. de; Aguiar, Monica Regina M.P. de [Universidade do Estado do Rio de Janeiro (UERJ), RJ (Brazil); Carbonell, Montserrat Motas [PETROBRAS, Rio de Janeiro, RJ (Brazil)

    2008-07-01

    In this study the process of co-pyrolysis of plastic polypropylene residues with gas-oil was evaluated, varying the temperature and the amount of polypropylene. The co-pyrolysis is a promising route to minimize the environmental impact caused by the inadequate plastic disposal, preventing its accumulation and giving a better use of the not renewable raw material (oil). The polypropylene samples and gas-oil were submitted to the thermal co-pyrolysis in inert atmosphere, varying the temperature from 400 deg C to 500 deg C and the amount of PP from 0,1 to 1,0 g. The influence of gas-oil was evaluated carrying the co-pyrolysis in the absence of PP. The pyrolyzed liquids produced by this thermal treatment had been characterized by modified gaseous chromatography objectifying the evaluation of the diesel fractions generation. As a result, the increase of PP amount lead to a reduction in the income of the pyrolytic liquid and to increase of the amount of solid generated. The effect of the increase of temperature showed an inverse result. The addition of PP in the reactor showed little interference in diesel range of distillation in the co-pyrolysis. On the other hand, an increase in temperature favors the increase of products in this range of distillation. The results show that plastic residue co-pyrolysis is a potential method of chemical recycling. (author)

  9. Treatment of post-consumption oils from Paraiba state - Brazil - clays for application as bio fuel; Tratamento de oleos pos-consumo a partir de argilas da Paraiba para aplicacao como biocombustivel

    Energy Technology Data Exchange (ETDEWEB)

    Araujo, E.P.; Oliveira, S.V. de; Medeiros, K.M. de; Silva, D.F. da; Araujo, E.M.; Fook, M.V.L. [Universidade Federal de Campina Grande (DEMa/UFCG), PB (Brazil). Dept. de Engenharia de Materiais], e-mail: elainepatriciaaraujo@yahoo.com.br

    2008-07-01

    The utilization of fuels of agricultural origin in the cycle diesel engines is a good alternative to reduce dependence on importation petroleum, since these fuels are a renewable source of energy. The utilization of biodiesel as biofuel is a contribution to the environment, reducing the qualitative and quantitative form levels of environmental pollution. The recycling of post-consumption oil helps reduce the uncontrolled disposal and environmentally dangerous, than to obtain fuel with a cost / benefit and offering a competitive alternative commercial advantage. However, these oils should go through a process of decontamination and clearing up the stage of chemical conversion which is used clay to lighten the oil. This work had as its objective to make a literature revision evaluating the potential of the clearing clay modified in Paraiba, used in post-consumption oils for application as biofuel. (author)

  10. Measuring receptor occupancy with PET

    NARCIS (Netherlands)

    van Waarde, A

    2000-01-01

    Many physiological and biochemical measurements can be performed noninvasively in humans with modern imaging techniques like magnetic resonance imaging (MRI), positron emission tomography (PET) or single-photon emission computed tomography (SPECT). This review focuses on the monitoring of

  11. PET and PET/CT in tumour of undetermined origin; PET y PET/CT en tumor de origen indeterminado

    Energy Technology Data Exchange (ETDEWEB)

    Garcia O, J.R. [Nuclear Medicine and Molecular Imaging, PET/CT, Centro Medico ABC, Mexico D.F. (Mexico)

    2007-07-01

    In this presentation the following conclusions were obtained regarding the use of PET and PET/CT in patient with cancer of unknown primary: 1. Detection of the primary one in 1/3 at 1/2 of patient. 2. It detects metastases in other places in 50%. 3. It changes the initial therapy planned in 1/3 at 1/2 of patient. 4. Useful in initial phases of protocol study to limit the other procedures. After standard evaluation. Before advanced protocol. 5. PET/CT study increases the % of primary detection, although in a non significant way vs. PET. 6. They are required more studies to value their utility to a more objective manner. (Author)

  12. Should immunocompromised patients have pets?

    Science.gov (United States)

    Steele, Russell W

    2008-01-01

    To evaluate the risks and benefits of pet ownership by immunodeficient patients, focusing primarily on organisms that colonize animals and are transmitted to humans. Those diseases that are known to be progressive or more severe in patients with altered immune function are emphasized. A review of the medical and veterinary literature pertaining to zoonoses transmitted by domestic animals was completed. Information pertaining to issues involving immunosuppressed patients including AIDS was carefully evaluated and summarized for inclusion. There are significant clinical and psychosocial benefits to pet ownership. However, numerous diseases can be acquired from these animals which may be more severe in immunocompromised individuals. Simple guidelines for pet ownership by immunosuppressed patients can be implemented to reduce their risk of disease and allow them to safely interchange with their pets.

  13. Pets and the immunocompromised person

    Science.gov (United States)

    ... affect the cat's immune system. This puts your cat at risk of other infections that may be spread to humans. Feed your pet only commercially prepared food and treats. Animals can get sick from undercooked ...

  14. Should pet owners be regulated?

    Science.gov (United States)

    Mills, Georgina

    2013-12-21

    To own a television, you have to have a licence, and to drive a car, you have to pass a test. However, there are no such limitations on owning a pet. Should this be changed, and what can be done to encourage more responsible pet ownership? This topic was discussed at the BVA Congress at the London Vet Show on November 21. Georgina Mills reports.

  15. Do carotid MR surface coils affect PET quantification in PET/MR imaging?

    Energy Technology Data Exchange (ETDEWEB)

    Willemink, Martin J; Eldib, Mootaz [Translational and Molecular Imaging Institute, Icahn School of Medicine at Mount Sinai, New York, NY (United States); Leiner, Tim [Department of Radiology, University Medical Center Utrecht, Utrecht (Netherlands); Fayad, Zahi A; Mani, Venkatesh [Translational and Molecular Imaging Institute, Icahn School of Medicine at Mount Sinai, New York, NY (United States)

    2015-05-18

    To evaluate the effect of surface coils for carotid MR imaging on PET quantification in a clinical simultaneous whole-body PET/MR scanner. A cylindrical phantom was filled with a homogeneous 2L water-FDG mixture at a starting dose of 301.2MBq. Clinical PET/MR and PET/CT systems were used to acquire PET-data without a coil (reference standard) and with two carotid MRI coils (Siemens Special Purpose 8-Channel and Machnet 4-Channel Phased Array). PET-signal attenuation was evaluated with Osirix using 51 (PET/MR) and 37 (PET/CT) circular ROIs. Mean and maximum standardized uptake values (SUVs) were quantified for each ROI. Furthermore, SUVs of PET/MR and PET/CT were compared. For validation, a patient was scanned with an injected dose of 407.7MBq on both a PET/CT and a PET/MR system without a coil and with both coils. PET/MR underestimations were -2.2% (Siemens) and -7.8% (Machnet) for SUVmean, and -1.2% (Siemens) and -3.3% (Machnet) for SUVmax, respectively. For PET/CT, underestimations were -1.3% (Siemens) and -1.4% (Machnet) for SUVmean and -0.5% (both Siemens and Machnet) for SUVmax, respectively using no coil data as reference. Except for PET/CT SUVmax values all differences were significant. SUVs differed significantly between PET/MR and PET/CT with SUVmean values of 0.51-0.55 for PET/MR and 0.68-0.69 for PET/CT, respectively. The patient examination showed that median SUVmean values measured in the carotid arteries decreased from 0.97 without a coil to 0.96 (Siemens) and 0.88 (Machnet). Carotid surface coils do affect attenuation correction in both PET/MR and PET/CT imaging. Furthermore, SUVs differed significantly between PET/MR and PET/CT.

  16. Game Design to Introduce Pets

    Directory of Open Access Journals (Sweden)

    Wahyu Febriyanto

    2017-02-01

    Full Text Available Introduction of animals from an early age can make children to love animals, especially pets. Children are the easiest group to receive stimulation, such as for example the stimulation of introducing children to the pet. Various media are used by parents to introduce pet. For examplle, by the media of books, multimedia, etc. One of the interesting media to introduce pet is with game. Of these problems then need to know how to make concept and design game to introduced pets for children age 3-6 years. In this paper, author formulate how to make pet game design include game genre, user interface design, image model selection, game characters, and game engine. The expected design of this game can be formulation of learning through proper game as a learning tool children. Game design derived from this writing by using model 2-dimensional images are funny and interesting coloring. And combines several game genres into one, or use the mini games that children do not get bored quickly. Design of GUI (Graphical User Interface is made as simple as possible so that children easily understand in playing this game, but also must use an interesting image

  17. Nutritional sustainability of pet foods.

    Science.gov (United States)

    Swanson, Kelly S; Carter, Rebecca A; Yount, Tracy P; Aretz, Jan; Buff, Preston R

    2013-03-01

    Sustainable practices meet the needs of the present without compromising the ability of future generations to meet their needs. Applying these concepts to food and feed production, nutritional sustainability is the ability of a food system to provide sufficient energy and essential nutrients required to maintain good health in a population without compromising the ability of future generations to meet their nutritional needs. Ecological, social, and economic aspects must be balanced to support the sustainability of the overall food system. The nutritional sustainability of a food system can be influenced by several factors, including the ingredient selection, nutrient composition, digestibility, and consumption rates of a diet. Carbon and water footprints vary greatly among plant- and animal-based ingredients, production strategy, and geographical location. Because the pet food industry is based largely on by-products and is tightly interlinked with livestock production and the human food system, however, it is quite unique with regard to sustainability. Often based on consumer demand rather than nutritional requirements, many commercial pet foods are formulated to provide nutrients in excess of current minimum recommendations, use ingredients that compete directly with the human food system, or are overconsumed by pets, resulting in food wastage and obesity. Pet food professionals have the opportunity to address these challenges and influence the sustainability of pet ownership through product design, manufacturing processes, public education, and policy change. A coordinated effort across the industry that includes ingredient buyers, formulators, and nutritionists may result in a more sustainable pet food system.

  18. What do we measure in oncology PET?

    Energy Technology Data Exchange (ETDEWEB)

    Pak, Kyoung June; Kim, Seong Jang [Dept. of Nuclear Medicine and Biomedical Research Institute, Pusan National University Hospital, Busan (Korea, Republic of)

    2017-09-15

    Positron emission tomography (PET) has come to the practice of oncology. It is known that {sup 18}F-fluorodeoxyglucose (FDG) PET is more sensitive for the assessment of treatment response than conventional imaging. In addition, PET has an advantage in the use of quantitative analysis of the study. Nowadays, various PET parameters are adopted in clinical settings. In addition, a wide range of factors has been known to be associated with FDG uptake. Therefore, there has been a need for standardization and harmonization of protocols and PET parameters. We will introduce PET parameters and discuss major issues in this review.

  19. Parasites in pet reptiles

    Directory of Open Access Journals (Sweden)

    Mavri Urška

    2011-05-01

    Full Text Available Abstract Exotic reptiles originating from the wild can be carriers of many different pathogens and some of them can infect humans. Reptiles imported into Slovenia from 2000 to 2005, specimens of native species taken from the wild and captive bred species were investigated. A total of 949 reptiles (55 snakes, 331 lizards and 563 turtles, belonging to 68 different species, were examined for the presence of endoparasites and ectoparasites. Twelve different groups (Nematoda (5, Trematoda (1, Acanthocephala (1, Pentastomida (1 and Protozoa (4 of endoparasites were determined in 26 (47.3% of 55 examined snakes. In snakes two different species of ectoparasites were also found. Among the tested lizards eighteen different groups (Nematoda (8, Cestoda (1, Trematoda (1, Acanthocephala (1, Pentastomida (1 and Protozoa (6 of endoparasites in 252 (76.1% of 331 examined animals were found. One Trombiculid ectoparasite was determined. In 563 of examined turtles eight different groups (Nematoda (4, Cestoda (1, Trematoda (1 and Protozoa (2 of endoparasites were determined in 498 (88.5% animals. In examined turtles three different species of ectoparasites were seen. The established prevalence of various parasites in reptiles used as pet animals indicates the need for examination on specific pathogens prior to introduction to owners.

  20. Parasites in pet reptiles.

    Science.gov (United States)

    Rataj, Aleksandra Vergles; Lindtner-Knific, Renata; Vlahović, Ksenija; Mavri, Urška; Dovč, Alenka

    2011-05-30

    Exotic reptiles originating from the wild can be carriers of many different pathogens and some of them can infect humans. Reptiles imported into Slovenia from 2000 to 2005, specimens of native species taken from the wild and captive bred species were investigated. A total of 949 reptiles (55 snakes, 331 lizards and 563 turtles), belonging to 68 different species, were examined for the presence of endoparasites and ectoparasites. Twelve different groups (Nematoda (5), Trematoda (1), Acanthocephala (1), Pentastomida (1) and Protozoa (4)) of endoparasites were determined in 26 (47.3%) of 55 examined snakes. In snakes two different species of ectoparasites were also found. Among the tested lizards eighteen different groups (Nematoda (8), Cestoda (1), Trematoda (1), Acanthocephala (1), Pentastomida (1) and Protozoa (6)) of endoparasites in 252 (76.1%) of 331 examined animals were found. One Trombiculid ectoparasite was determined. In 563 of examined turtles eight different groups (Nematoda (4), Cestoda (1), Trematoda (1) and Protozoa (2)) of endoparasites were determined in 498 (88.5%) animals. In examined turtles three different species of ectoparasites were seen. The established prevalence of various parasites in reptiles used as pet animals indicates the need for examination on specific pathogens prior to introduction to owners.

  1. Detection of Cancer with PET and PET/CT in Asymptomatic Volunteers

    Energy Technology Data Exchange (ETDEWEB)

    Chung, Ji In; Choi, Joon Young; Lee, Kyung Han; Kim, Byung Tae; Choi, Yoon Ho [Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of); Cho, Han Byoul; Shim, Jae Yong [The Graduate School of Yonsei University, Seoul (Korea, Republic of)

    2009-12-15

    We retrospectively investigated the diagnostic performance of {sup 18}F-fluorodeoxyglucose positron emission tomography (PET) and PET/CT for cancer detection in asymptomatic health-check examinees. This study consisted of 5091 PET or PET/CT conducted as part of annual health examination at one hospital from March 1998 to February 2008. To find the incidence of cancers, medical records of the subjects were thoroughly reviewed for a follow-up period of one year. The patterns of formal readings of PET and PET/CT were analyzed to assess the sensitivity and specificity for cancer detection. The histopathology and stage of the cancers were evaluated in relation to the results of PET. Eighty-six cancers (1.7%) were diagnosed within one year after PET or PET/CT. When PET and PET/CT results were combined, the sensitivity was 48.8% and specificity was 81.1% for cancer detection. PET only had a sensitivity of 46.2% and a specificity of 81.4%, and PET/CT only had a sensitivity of 75.0% and a specificity of 78.5% respectively. There were no significant differences in cancer site, stage and histopathology between PET positive and PET negative cancers. In 19.3% of formal readings of PET and PET/CT, further evaluation to exclude malignancy or significant disease was recommended. Head and neck area and upper gastrointestinal tract were commonly recommended sites for further evaluation. PET and PET/CT showed moderate performance for detecting cancers in asymptomatic adults in this study. More experience and further investigation are needed to overcome limitations of PET and PET/CT for cancer screening.

  2. Quantitative PET imaging with the 3T MR-BrainPET

    Energy Technology Data Exchange (ETDEWEB)

    Weirich, C., E-mail: c.weirich@fz-juelich.de [Forschungszentrum Jülich, Institute of Neuroscience and Medicine – 4, Juelich (Germany); Scheins, J.; Lohmann, P.; Tellmann, L. [Forschungszentrum Jülich, Institute of Neuroscience and Medicine – 4, Juelich (Germany); Byars, L.; Michel, C. [Siemens Healthcare, Molecular Imaging, Knoxville, TN (United States); Rota Kops, E.; Brenner, D.; Herzog, H.; Shah, N.J. [Forschungszentrum Jülich, Institute of Neuroscience and Medicine – 4, Juelich (Germany)

    2013-02-21

    The new hybrid imaging technology of MR-PET allows for simultaneous acquisition of versatile MRI contrasts and the quantitative metabolic imaging with PET. In order to achieve the quantification of PET images with minimal residual error the application of several corrections is crucial. In this work we present our results on quantification with the 3T MR BrainPET scanner.

  3. Combined PET/MR imaging in neurology

    DEFF Research Database (Denmark)

    Andersen, Flemming Littrup; Ladefoged, Claes Nøhr; Beyer, Thomas

    2014-01-01

    ). RESULTS: PET activity values in patients following MR-AC (A) showed a substantial radial dependency when compared to PET/CT. In all patients cortical PET activity was lower than the activity in the central region of the brain (10-15%). When adding bone attenuation values to standard MR-AC (B and C......) the radial gradient of PET activity values was removed. Further evaluation of PET/MR activity following MR-AC (A) relative to MR-AC (C) using the full CT for attenuation correction showed an underestimation of 25% in the cortical regions and 5-10% in the central regions of the brain. Observations in patients...... were replicated by observations from the phantom study. CONCLUSION: Our phantom and patient data demonstrate a spatially varying bias of the PET activity in PET/MR images of the brain when bone tissue is not accounted for during attenuation correction. This has immediate implications for PET/MR imaging...

  4. Magnetic Resonance-based Motion Correction for Quantitative PET in Simultaneous PET-MR Imaging.

    Science.gov (United States)

    Rakvongthai, Yothin; El Fakhri, Georges

    2017-07-01

    Motion degrades image quality and quantitation of PET images, and is an obstacle to quantitative PET imaging. Simultaneous PET-MR offers a tool that can be used for correcting the motion in PET images by using anatomic information from MR imaging acquired concurrently. Motion correction can be performed by transforming a set of reconstructed PET images into the same frame or by incorporating the transformation into the system model and reconstructing the motion-corrected image. Several phantom and patient studies have validated that MR-based motion correction strategies have great promise for quantitative PET imaging in simultaneous PET-MR. Copyright © 2017 Elsevier Inc. All rights reserved.

  5. Efeitos do processamento químico e da esterilização em Óxido de etileno em osso cortical e esponjoso de ratas: estudo com microscopia de luz e eletrônica de varredura Effects of chemical processing and oxide ethylene sterilization on cortical and cancellous rat bone: a light and electron scanning microscopy study

    Directory of Open Access Journals (Sweden)

    Marcello Teixeira Castiglia

    2009-02-01

    Full Text Available OBJETIVO: Avaliar, sob o ponto de vista microscópico, modificações estruturais do osso esponjoso e cortical, após serem submetidos a processamento químico e esterilização em óxido de etileno. MÉTODOS: Amostras de osso esponjoso e cortical foram obtidas de fêmures de ratas albinas jovens (Wistare separadas em quatro grupos contendo osso cortical e esponjoso: I- Fragmentos secos em estufa; II- Fragmentos secos em estufa e esterilizados em óxido de etileno; III- Fragmentos processados quimicamente; IV- Fragmentos processados quimicamente e esterilizados em óxido de etileno. Metade desse material foi analisada em microscópio eletrônico de varredura e, a outra metade, em microscopia de luz convencional. RESULTADOS: Houve preservação da morfologia geral das amostras em todos os grupos. Nos grupos submetidos ao processamento químico houve melhor preservação do conteúdo celular, enquanto que naqueles submetido ao óxido de etileno houve amalgamação fibrilar. CONCLUSÃO: O tratamento com óxido de etileno causou amalgamação das fibrilas possivelmente em decorrência do efeito do calor e o tratamento químico contribuiu para melhor preservação da estrutura óssea.OBJECTIVE: To evaluate, under microscopic examination, the structural changes displayed by the trabecular and cortical bones after being processed chemically and sterilized by ethylene oxide. METHODS: Samples of cancellous and cortical bones obtained from young female albinus rats (Wistar were assigned to four groups according to the type of treatment: Group I-drying; Group II-drying and ethylene oxide sterilization; III-chemical treatment; IV-chemical treatment and ethylene oxide sterilization. Half of this material was analyzed under ordinary light microscope and the other half using scanning electron microscopy. RESULTS: In all the samples, regardless the group, there was good preservation of the general morphology. For samples submitted to the chemical processing

  6. Comparison of PET/CT with sequential PET/MRI using an MR-compatible mobile PET system.

    Science.gov (United States)

    Nakamoto, Ryusuke; Nakamoto, Yuji; Ishimori, Takayoshi; Fushimi, Yasutaka; Kido, Aki; Togashi, Kaori

    2017-11-02

    Objectives: The current study tested a newly developed flexible PET (positron emission tomography) scanner prototype. This flexible PET (fxPET) system involves dual arc-shaped detectors based on silicon photomultipliers, which are designed to fit existing magnetic resonance (MR) devices, allowing us to get fused PET and MR images by sequential PET scanning. This prospective study sought to evaluate image quality, lesion detection rate, and quantitative values of fxPET in comparison with conventional whole-body (WB) PET images, and to assess the accuracy of registration. Methods: Seventeen patients with suspected or known malignant tumors were analyzed. Approximately 1 h after intravenous injection of (18)F-fluorodeoxyglucose (FDG), WB PET/computed tomography (CT) scanning was performed, followed by fxPET and MR scanning. For reconstruction of fxPET images, MRI-based attenuation correction was applied. The quality of fxPET images was visually assessed, and the number of detected lesions was compared between the two imaging methods. The maximum standardized uptake values (SUVmax) and maximum average SUV within a 1 cm(3) spherical volume (SUVpeak) of lesions were also compared. In addition, the magnitude of misregistration between fxPET and MR images was evaluated. Results: The image quality of fxPET was acceptable for diagnosis of malignant tumors. There was no significant difference in detectability of malignant lesions between fxPET and WB PET (P > 0.05). However, the system did not exhibit superior performance compared with WB PET. There were strong positive correlations between the two imaging modalities in SUVmax (ρ = 0.88) and SUVpeak (ρ = 0.81). SUVmax and SUVpeak measured with fxPET were approximately 1.1-fold greater compared with WB PET measurements. The average misregistration between fxPET and MR images was 5.5 ± 3.4 mm. Conclusion: Our preliminary data indicate that running a fxPET scanner in the proximity of an existing MR system provided visually

  7. Validating PET segmentation of thoracic lesions-is 4D PET necessary?

    DEFF Research Database (Denmark)

    Nielsen, M. S.; Carl, J.

    2017-01-01

    Respiratory-induced motions are prone to degrade the positron emission tomography (PET) signal with the consequent loss of image information and unreliable segmentations. This phantom study aims to assess the discrepancies relative to stationary PET segmentations, of widely used semiautomatic PET...... segmented using three SUV threshold methods (Max40%, SUV40% and 2.5SUV) and a gradient based method (GradientSeg). Segmentations in static 3D-PET scans (PETsta) specified the reference conditions for the individual segmentation methods, target lesions and tracer concentrations. The motion included PET...... images followed a 4D-PET (PET4D) and a 3D-PET (PETmot) scan protocol. Moreover, motion-corrected PET images (PETdeb) were derived from the PETmot images. Segmentations in PET4D, PETmot and PETdeb were compared to the PETsta segmentations according to volume changes (Delta Vol) and an error estimate (low...

  8. Pet care during preadolescence: developmental considerations.

    Science.gov (United States)

    Davis, J H

    1987-01-01

    This exploratory study investigated pet care in relation to psychosocial development during preadolescence. A group of male and female preadolescents (n = 22) at appropriate grade level for age completed a dog care responsibility inventory. The results revealed that preadolescents in general do not routinely care for pets. Mothers appear to assume most pet care tasks.

  9. Pet therapy: dogs de-stress students.

    Science.gov (United States)

    Young, Judith S

    2012-01-01

    Research supports the efficacy of the human-animal bond and pet therapy in a variety of settings. At nursing students' request at one school, the author began offering pet therapy prior to examinations. Anecdotal evidence of a study with the author's Golden Retriever, Goldilocks, demonstrates that pet therapy can reduce test anxiety and improve nursing student performance.

  10. Saying Goodbye: Pet Loss and Its Implications

    Science.gov (United States)

    Duffey, Thelma

    2005-01-01

    Pets can be loyal, loving, and entertaining members of a family. Their deaths are generally experienced as painful losses by the people who love them, even though the grief experience is often culturally disenfranchised. In this manuscript, we discuss the role that pets can play in a person's life; the effects that pet loss can have on the people…

  11. Pets in the family: practical approaches.

    Science.gov (United States)

    Hodgson, Kate; Darling, Marcia

    2011-01-01

    Adapting family life cycle theory to include pets provides veterinarians with a framework for understanding and reinforcing the human-animal bond. The family genogram with pets is a practice tool that identifies all people and pets in the family, enhancing the practice of One Health at the community level.

  12. Pets or People: Another Research Note.

    Science.gov (United States)

    Goldmeier, John

    1986-01-01

    Compared four samples of elderly women: living alone, with other persons, and with and without a pet. Pets only made a difference for those living alone. At best, pets only attenuate the sense of loneliness. In intervention with the elderly, the provision of human supports should remain a priority. (Author/BL)

  13. THE CHARACTERISTICS OF EEC PET INSTRUMENTATION

    NARCIS (Netherlands)

    PAANS, AMJ

    1991-01-01

    As a result of a Guide-Questionnaire distributed among all European PET centers an inventory of the European PET instrumentation has become available in a data base. An overview and analysis of the European PET equipment, cyclotrons, scanners and software, together with some global information on

  14. 24 CFR 960.707 - Pet ownership.

    Science.gov (United States)

    2010-04-01

    ... 24 Housing and Urban Development 4 2010-04-01 2010-04-01 false Pet ownership. 960.707 Section 960... ADMISSION TO, AND OCCUPANCY OF, PUBLIC HOUSING Pet Ownership in Public Housing § 960.707 Pet ownership. (a) Ownership Conditions. A resident of a dwelling unit in public housing, as that term is used in § 960.703...

  15. PET/MRI. Challenges, solutions and perspectives

    Energy Technology Data Exchange (ETDEWEB)

    Herzog, Hans [Forschungszentrum Juelich (Germany). Inst. of Neuroscience and Medicine - 4

    2012-07-01

    Already from the start of PET/CT integrating positron emission tomography (PET) and computed tomography (CT) in one instrument, there have been considerations how to combine PET and magnetic resonance imaging (MRI) so that their complementary abilities can be utilized in a single investigation. Since classical PET electronics fail in an even weak magnetic field and PET signal processing might disturb high-frequency signals of MRI, it soon became clear that new solutions had to be found to avoid mutual interferences. During the last fifteen years a number of different approaches towards PET/MRI for small animal imaging have been developed by research groups which together with their specific features are summarized in this review. Recently, PET/MRI for human imaging became available as well - this time by industrial initiatives. First some prototypes of BrainPET/MRI were developed followed by commercial products for simultaneous and non-simultaneous whole-body PET/MRI. Although only PET/MRI integrated in one scanner offers the full diversity of complementary multiparametric imaging, there are also promising applications of non-simultaneous sequential PET/MRI. While describing the present instrumentation for human PET/MRI, this review discusses the challenges and promises related to this new imaging technology. (orig.)

  16. PET Metabolic Biomarkers for Cancer

    Directory of Open Access Journals (Sweden)

    Etienne Croteau

    2016-01-01

    Full Text Available The body's main fuel sources are fats, carbohydrates (glucose, proteins, and ketone bodies. It is well known that an important hallmark of cancer cells is the overconsumption of glucose. Positron emission tomography (PET imaging using the glucose analog 18 F-fluorodeoxyglucose ( 18 F-FDG has been a powerful cancer diagnostic tool for many decades. Apart from surgery, chemotherapy and radiotherapy represent the two main domains for cancer therapy, targeting tumor proliferation, cell division, and DNA replication–-all processes that require a large amount of energy. Currently, in vivo clinical imaging of metabolism is performed almost exclusively using PET radiotracers that assess oxygen consumption and mechanisms of energy substrate consumption. This paper reviews the utility of PET imaging biomarkers for the detection of cancer proliferation, vascularization, metabolism, treatment response, and follow-up after radiation therapy, chemotherapy, and chemotherapy-related side effects.

  17. PET and SPECT in neurology

    Energy Technology Data Exchange (ETDEWEB)

    Dierckx, Rudi A.J.O. [Groningen University Medical Center (Netherlands). Dept. of Nuclear Medicine and Molecular Imaging; Ghent Univ. (Belgium). Dept. of Radiology and Nuclear Medicine; Vries, Erik F.J. de; Waarde, Aren van [Groningen University Medical Center (Netherlands). Dept. of Nuclear Medicine and Molecular Imaging; Otte, Andreas (ed.) [Univ. of Applied Sciences Offenburg (Germany). Faculty of Electrical Engineering and Information Technology

    2014-07-01

    PET and SPECT in Neurology highlights the combined expertise of renowned authors whose dedication to the investigation of neurological disorders through nuclear medicine technology has achieved international recognition. Classical neurodegenerative disorders are discussed as well as cerebrovascular disorders, brain tumors, epilepsy, head trauma, coma, sleeping disorders, and inflammatory and infectious diseases of the CNS. The latest results in nuclear brain imaging are detailed. Most chapters are written jointly by a clinical neurologist and a nuclear medicine specialist to ensure a multidisciplinary approach. This state-of-the-art compendium will be valuable to anybody in the field of neuroscience, from the neurologist and the radiologist/nuclear medicine specialist to the interested general practitioner and geriatrician. It is the second volume of a trilogy on PET and SPECT imaging in the neurosciences, the other volumes covering PET and SPECT in psychiatry and in neurobiological systems.

  18. Competitive advantage of PET/MRI

    Energy Technology Data Exchange (ETDEWEB)

    Jadvar, Hossein, E-mail: jadvar@usc.edu; Colletti, Patrick M.

    2014-01-15

    Multimodality imaging has made great strides in the imaging evaluation of patients with a variety of diseases. Positron emission tomography/computed tomography (PET/CT) is now established as the imaging modality of choice in many clinical conditions, particularly in oncology. While the initial development of combined PET/magnetic resonance imaging (PET/MRI) was in the preclinical arena, hybrid PET/MR scanners are now available for clinical use. PET/MRI combines the unique features of MRI including excellent soft tissue contrast, diffusion-weighted imaging, dynamic contrast-enhanced imaging, fMRI and other specialized sequences as well as MR spectroscopy with the quantitative physiologic information that is provided by PET. Most evidence for the potential clinical utility of PET/MRI is based on studies performed with side-by-side comparison or software-fused MRI and PET images. Data on distinctive utility of hybrid PET/MRI are rapidly emerging. There are potential competitive advantages of PET/MRI over PET/CT. In general, PET/MRI may be preferred over PET/CT where the unique features of MRI provide more robust imaging evaluation in certain clinical settings. The exact role and potential utility of simultaneous data acquisition in specific research and clinical settings will need to be defined. It may be that simultaneous PET/MRI will be best suited for clinical situations that are disease-specific, organ-specific, related to diseases of the children or in those patients undergoing repeated imaging for whom cumulative radiation dose must be kept as low as reasonably achievable. PET/MRI also offers interesting opportunities for use of dual modality probes. Upon clear definition of clinical utility, other important and practical issues related to business operational model, clinical workflow and reimbursement will also be resolved.

  19. Competitive advantage of PET/MRI.

    Science.gov (United States)

    Jadvar, Hossein; Colletti, Patrick M

    2014-01-01

    Multimodality imaging has made great strides in the imaging evaluation of patients with a variety of diseases. Positron emission tomography/computed tomography (PET/CT) is now established as the imaging modality of choice in many clinical conditions, particularly in oncology. While the initial development of combined PET/magnetic resonance imaging (PET/MRI) was in the preclinical arena, hybrid PET/MR scanners are now available for clinical use. PET/MRI combines the unique features of MRI including excellent soft tissue contrast, diffusion-weighted imaging, dynamic contrast-enhanced imaging, fMRI and other specialized sequences as well as MR spectroscopy with the quantitative physiologic information that is provided by PET. Most evidence for the potential clinical utility of PET/MRI is based on studies performed with side-by-side comparison or software-fused MRI and PET images. Data on distinctive utility of hybrid PET/MRI are rapidly emerging. There are potential competitive advantages of PET/MRI over PET/CT. In general, PET/MRI may be preferred over PET/CT where the unique features of MRI provide more robust imaging evaluation in certain clinical settings. The exact role and potential utility of simultaneous data acquisition in specific research and clinical settings will need to be defined. It may be that simultaneous PET/MRI will be best suited for clinical situations that are disease-specific, organ-specific, related to diseases of the children or in those patients undergoing repeated imaging for whom cumulative radiation dose must be kept as low as reasonably achievable. PET/MRI also offers interesting opportunities for use of dual modality probes. Upon clear definition of clinical utility, other important and practical issues related to business operational model, clinical workflow and reimbursement will also be resolved. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  20. Respiração e produção de etanol e de etileno em mangas armazenadas sob diferentes concentrações de dióxido de carbono e oxigênio

    Directory of Open Access Journals (Sweden)

    BENDER RENAR JOÃO

    2000-01-01

    Full Text Available O objetivo deste trabalho foi avaliar a respiração e produção de etanol e etileno em mangas armazenadas sob reduzidas concentrações de oxigênio (O2 e elevadas concentrações de dióxido de carbono (CO2. Mangas pré-climatéricas das cultivares Kent e Tommy Atkins foram armazenadas, sob fluxo contínuo, por 14 ou 21 dias, a 12°C em três concentrações de O2: 3%, 5% ou 21% em mistura com concentrações de 5%, 15%, 25%, 35%, 45%, 50% ou 70% de CO2. O tratamento-testemunha constou de armazenagem em ar sob fluxo contínuo. Após o período em atmosfera controlada (AC, as mangas foram transferidas e mantidas por 5 dias em ar a 20°C. Mangas sob concentrações de 50% e 70% de CO2 produziram mais etanol que nas demais concentrações de CO2. A redução para 3% de O2 na atmosfera de armazenagem aparentemente não teve efeito adicional ao CO2 na produção de etanol. A atividade respiratória de mangas em AC com CO2 acima de 45% foi muito mais intensa do que a respiração sob as concentrações de CO2 mais baixas; a produção de etileno, no entanto, esteve suprimida, e, mesmo após a transferência para ar, não se recuperou, permanecendo inferior aos demais tratamentos. A queda na atividade respiratória das mangas armazenadas a 50% e 70% de CO2, quando foram transferidas para ar a 20°C indica que as elevadas concentrações de CO2 causaram dano irreparável aos tecidos.

  1. Kinetic modeling in PET imaging of hypoxia

    DEFF Research Database (Denmark)

    Joergensen, Jesper T; Hansen, Anders E; Kjaer, Andreas

    2014-01-01

    be used for non-invasive mapping of tissue oxygenation in vivo and several hypoxia specific PET tracers have been developed. Evaluation of PET data in the clinic is commonly based on visual assessment together with semiquantitative measurements e.g. standard uptake value (SUV). However, dynamic PET......Tumor hypoxia is associated with increased therapeutic resistance leading to poor treatment outcome. Therefore the ability to detect and quantify intratumoral oxygenation could play an important role in future individual personalized treatment strategies. Positron Emission Tomography (PET) can...... analysis for PET imaging of hypoxia....

  2. FDG-PET response-adapted therapy

    DEFF Research Database (Denmark)

    Hutchings, Martin

    2014-01-01

    Fluorodeoxyglucose (FDG) positron emission tomography (PET)/computed tomography (CT) is the most accurate tool for staging, treatment monitoring, and response evaluation in Hodgkin lymphoma (HL). Early determination of treatment sensitivity by FDG-PET is the best tool to guide individualized......, response-adapted treatment. Several ongoing or recently completed trials have investigated the use of FDG-PET/CT for early response-adapted HL therapy. The results are encouraging, but the data are immature, and PET response-adapted HL therapy is discouraged outside the setting of clinical trials. PET...

  3. Cardiac Applications of PET/MR Imaging.

    Science.gov (United States)

    Lau, Jeffrey M C; Laforest, Richard; Nensa, Felix; Zheng, Jie; Gropler, Robert J; Woodard, Pamela K

    2017-05-01

    Simultaneous acquisition PET/MR imaging combines the anatomic capabilities of cardiac MR imaging with quantitative capabilities of both PET and MR imaging. Cardiac PET/MR imaging has the potential not only to assess cardiac tumors but also to provide thorough assessment of myocardial ischemia, infarction, and function and specific characterization of cardiomyopathies, such as cardiac sarcoid. In this article, the authors start with a discussion of the technical challenges specific to cardiovascular PET/MR imaging followed by a discussion of the use of PET/MR imaging in various cardiovascular conditions. Copyright © 2016 Elsevier Inc. All rights reserved.

  4. PET/CT in the thorax: pitfalls.

    Science.gov (United States)

    Truong, Mylene T; Viswanathan, Chitra; Carter, Brett W; Mawlawi, Osama; Marom, Edith M

    2014-01-01

    PET/CT is widely used in the staging and assessment of therapeutic response in patients with malignancies. Accurate interpretation of PET/CT requires knowledge of the normal physiologic distribution of [18F]-fluoro-2-deoxy-d-glucose, artifacts due to the use of CT for attenuation correction of the PET scan and potential pitfalls due to malignancies that are PET negative and benign conditions that are PET positive. Awareness of these artifacts and potential pitfalls is important in preventing misinterpretation that can alter patient management. Copyright © 2014 Elsevier Inc. All rights reserved.

  5. Kinetic modeling in PET imaging of hypoxia

    DEFF Research Database (Denmark)

    Li, Fan; Jørgensen, Jesper Tranekjær; Hansen, Anders E

    2014-01-01

    Tumor hypoxia is associated with increased therapeutic resistance leading to poor treatment outcome. Therefore the ability to detect and quantify intratumoral oxygenation could play an important role in future individual personalized treatment strategies. Positron Emission Tomography (PET) can...... be used for non-invasive mapping of tissue oxygenation in vivo and several hypoxia specific PET tracers have been developed. Evaluation of PET data in the clinic is commonly based on visual assessment together with semiquantitative measurements e.g. standard uptake value (SUV). However, dynamic PET...... analysis for PET imaging of hypoxia....

  6. Development of PET/MRI with insertable PET for simultaneous PET and MR imaging of human brain

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Jin Ho; Choi, Yong, E-mail: ychoi.image@gmail.com; Jung, Jiwoong; Kim, Sangsu; Lim, Hyun Keong; Im, Ki Chun [Department of Electronic Engineering, Sogang University, 35 Baekbeom-ro, Mapo-gu, Seoul 121-742 (Korea, Republic of); Oh, Chang Hyun; Park, Hyun-wook [Department of Electrical Engineering, Korea Advanced Institute of Science and Technology, 291 Daehak-ro, Yuseong-gu, Daejeon 305-701 (Korea, Republic of); Kim, Kyung Min; Kim, Jong Guk [Korea Institute of Radiological and Medical Science, 75 Nowon-ro, Nowon-gu, Seoul 139-709 (Korea, Republic of)

    2015-05-15

    Purpose: The purpose of this study was to develop a dual-modality positron emission tomography (PET)/magnetic resonance imaging (MRI) with insertable PET for simultaneous PET and MR imaging of the human brain. Methods: The PET detector block was composed of a 4 × 4 matrix of detector modules, each consisting of a 4 × 4 array LYSO coupled to a 4 × 4 Geiger-mode avalanche photodiode (GAPD) array. The PET insert consisted of 18 detector blocks, circularly mounted on a custom-made plastic base to form a ring with an inner diameter of 390 mm and axial length of 60 mm. The PET gantry was shielded with gold-plated conductive fabric tapes with a thickness of 0.1 mm. The charge signals of PET detector transferred via 4 m long flat cables were fed into the position decoder circuit. The flat cables were shielded with a mesh-type aluminum sheet with a thickness of 0.24 mm. The position decoder circuit and field programmable gate array-embedded DAQ modules were enclosed in an aluminum box with a thickness of 10 mm and located at the rear of the MR bore inside the MRI room. A 3-T human MRI system with a Larmor frequency of 123.7 MHz and inner bore diameter of 60 cm was used as the PET/MRI hybrid system. A custom-made radio frequency (RF) coil with an inner diameter of 25 cm was fabricated. The PET was positioned between gradient and the RF coils. PET performance was measured outside and inside the MRI scanner using echo planar imaging, spin echo, turbo spin echo, and gradient echo sequences. MRI performance was also evaluated with and without the PET insert. The stability of the newly developed PET insert was evaluated and simultaneous PET and MR images of a brain phantom were acquired. Results: No significant degradation of the PET performance caused by MR was observed when the PET was operated using various MR imaging sequences. The signal-to-noise ratio of MR images was slightly degraded due to the PET insert installed inside the MR bore while the homogeneity was

  7. Understanding the context for pet cat and dog feeding and exercising behaviour among pet owners in Ireland: a qualitative study.

    Science.gov (United States)

    Downes, Martin J; Devitt, Catherine; Downes, Marie T; More, Simon J

    2017-01-01

    Pet cat and dog obesity contributes to increased risk of several diseases, including cancer and diabetes mellitus as well as a worsening of orthopaedic problems, and a reduction in survival rate. This study aims to develop a better understanding of cat and dog owners' self-reported beliefs and factors that influence owner behaviour around feeding and exercising their pet cat or dog, as there is a lack of in-depth understanding in this area. Seven focus group discussions, with 43 pet owners in total, were conducted. Pet owners often reported a perceived a low level of control over feeding; often undermined by other people feeding of their pet, their pets begging for food, and their pets attitude towards food. Treats were used in the absence of owner control over pet begging and emotional attachment, and to influence pet behaviour. The majority of participants had positive attitudes to pet exercise, which could be related to pet specific requirements, especially differences in cats and dogs. There were some negative experiences of stress associated with dog walking and fears over aggressive confrontations with other dogs. Feeding one's pet is influenced by beliefs about pet specific needs, pet food and pet health, pet owners' perceived control over feeding, and the implications for the pet owner. Pet exercise is influenced by beliefs about pet specific exercise needs, and the implications of exercising one's pet for the pet owner. Understanding owner behaviours on feeding and exercise allows for a more targeted approach to preventing and treating pet obesity.

  8. Effect of Attenuation Correction on Regional Quantification Between PET/MR and PET/CT

    DEFF Research Database (Denmark)

    Teuho, Jarmo; Johansson, Jarkko; Linden, Jani

    2016-01-01

    UNLABELLED: A spatial bias in brain PET/MR exists compared with PET/CT, because of MR-based attenuation correction. We performed an evaluation among 4 institutions, 3 PET/MR systems, and 4 PET/CT systems using an anthropomorphic brain phantom, hypothesizing that the spatial bias would be minimized...... with CT-based attenuation correction (CTAC). METHODS: The evaluation protocol was similar to the quantification of changes in neurologic PET studies. Regional analysis was conducted on 8 anatomic volumes of interest (VOIs) in gray matter on count-normalized, resolution-matched, coregistered data. On PET/MR...... systems, CTAC was applied as the reference method for attenuation correction. RESULTS: With CTAC, visual and quantitative differences between PET/MR and PET/CT systems were minimized. Intersystem variation between institutions was +3.42% to -3.29% in all VOIs for PET/CT and +2.15% to -4.50% in all VOIs...

  9. PET/MR Imaging in Gynecologic Oncology.

    Science.gov (United States)

    Ohliger, Michael A; Hope, Thomas A; Chapman, Jocelyn S; Chen, Lee-May; Behr, Spencer C; Poder, Liina

    2017-08-01

    MR imaging and PET using 2-Deoxy-2-[18F]fluoroglucose (FDG) are both useful in the evaluation of gynecologic malignancies. MR imaging is superior for local staging of disease whereas fludeoxyglucose FDG PET is superior for detecting distant metastases. Integrated PET/MR imaging scanners have great promise for gynecologic malignancies by combining the advantages of each modality into a single scan. This article reviews the technology behind PET/MR imaging acquisitions and technical challenges relevant to imaging the pelvis. A dedicated PET/MR imaging protocol; the roles of PET and MR imaging in cervical, endometrial, and ovarian cancers; and future directions for PET/MR imaging are discussed. Copyright © 2017 Elsevier Inc. All rights reserved.

  10. Citotoxicidade de tubos de PVC esterilizados em óxido de etileno após exposição à radiação gama Citotoxicidad de tubos de PVC esterilizados en óxido de etileno luego de exposición a la radiación gamma Cytotoxicity of PVC tubes sterilized in ethylene oxide after gamma radiation exposure

    Directory of Open Access Journals (Sweden)

    Rafael Queiroz de Souza

    2013-04-01

    Full Text Available Materiais esterilizados em raios gama, ao serem re-esterilizados em óxido de etileno (EO, formam substâncias tóxicas? Esta questão norteou o objetivo deste estudo, que foi investigar o potencial efeito citotóxico do PVC esterilizado em radiação gama e re-esterilizado em EO pelo método da difusão em ágar em culturas celulares. Nove tubos de PVC foram submetidos à esterilização em radiação gama e re-esterilizados em EO. Os tubos foram divididos em um total de 81 unidades de análise, que foram testadas de forma a representar as superfícies internas, externas e massa de cada tubo. Concluiu-se que os materiais de PVC esterilizados em Radiação Gama e consecutivamente re-esterilizados em EO não são citotóxicos.Los materiales esterilizados con rayos gama, al ser re-esterilizados en óxido de etileno (EO, ¿forman substancias tóxicas? Esta pregunta orientó el objetivo del presente estudio, que fue investigar el potencial efecto citotóxico del PVC esterilizado en radiación gamma y re-esterilizado en EO por el método de difusión en agar en cultivos celulares. Nueve tubos de PVC fueron sometidos a esterilización por radiación gamma y re-esterilizados en EO. Se les aplicaron en total 81 unidades de análisis, las cuales fueron testeadas de manera tal de representar las superficies internas, externas y la masa de cada tubo. Se concluyó en que los materiales de PVC esterilizados con Radiación Gamma y, posteriormente, con EO, no son citotóxicos.Do materials sterilized using gamma rays become toxic when re-sterilized in ethylene oxide? This question guided the objective of this study, which was to investigate the potential cytotoxic effect of PVC sterilized by gamma radiation and re-sterilized with EO by the agar diffusion method in cell cultures. Nine PVC tubes were subjected to gamma radiation sterilization and were re-sterilized in EO. The tubes were divided into a total of 81 units of analysis that were tested so as to

  11. PET and SPECT in psychiatry

    Energy Technology Data Exchange (ETDEWEB)

    Dierckx, Rudi A.J.O. [University Medical Center Groningen (Netherlands). Dept. of Nuclear Medicine and Molecular Imaging; Ghent Univ. (Belgium); Otte, Andreas [Univ. of Applied Sciences Offenburg (Germany). Faculty of Electrical Engineering and Information Technology; Vries, Erik F.J. de; Waarde, Aren van (eds.) [University Medical Center Groningen (Netherlands). Dept. of Nuclear Medicine and Molecular Imaging

    2014-09-01

    Covers classical psychiatric disorders as well as other subjects such as suicide, sleep, eating disorders, and autism. Emphasis on a multidisciplinary approach. Written by internationally acclaimed experts. PET and SPECT in Psychiatry showcases the combined expertise of renowned authors whose dedication to the investigation of psychiatric disease through nuclear medicine technology has achieved international recognition. The classical psychiatric disorders as well as other subjects - such as suicide, sleep, eating disorders, and autism - are discussed and the latest results in functional neuroimaging are detailed. Most chapters are written jointly by a clinical psychiatrist and a nuclear medicine expert to ensure a multidisciplinary approach. This state of the art compendium will be valuable to all who have an interest in the field of neuroscience, from the psychiatrist and the radiologist/nuclear medicine specialist to the interested general practitioner and cognitive psychologist. It is the first volume of a trilogy on PET and SPECT imaging in the neurosciences; other volumes will focus on PET and SPECT in neurology and PET and SPECT of neurobiological systems.

  12. Should Immunocompromised Patients Have Pets?

    OpenAIRE

    Steele, Russell W.

    2008-01-01

    Purpose: To evaluate the risks and benefits of pet ownership by immunodeficient patients, focusing primarily on organisms that colonize animals and are transmitted to humans. Those diseases that are known to be progressive or more severe in patients with altered immune function are emphasized.

  13. 10 "Poison Pills" for Pets

    Science.gov (United States)

    ... Naprosyn®) is an over-the-counter pain reliever. Dogs and cats are very sensitive to naproxen and even small amounts can cause stomach ulcers and kidney failure. Duloxetine – Duloxetine (Cymbalta®) is prescribed as an antidepressant and anti-anxiety agent. When ingested by pets it can cause ...

  14. Particle Accelerators for PET radionuclides

    DEFF Research Database (Denmark)

    Jensen, Mikael

    2012-01-01

    The requirements set for particle accelerators for production of radioactive isotopes for PET can easily be derived from first principles. The simple general need is for proton beams with energy in the region 10–20 MeV and current 20–100 microAmps. This is most reliably and cost-effectively achie......The requirements set for particle accelerators for production of radioactive isotopes for PET can easily be derived from first principles. The simple general need is for proton beams with energy in the region 10–20 MeV and current 20–100 microAmps. This is most reliably and cost...... different manufacturers will be discussed the light of what is actually needed for a given PET site operation. Alternatives to the conventional cyclotron have been proposed and tested but have at present very limited use. These alternatives will be discussed, as well as the future possibilities of supplying...... point of demand tracer production with very small cyclotrons of energy well below 10 MeV. The authors best advice at present for new PET sites is to negotiate for conventional cyclotron solutions from experienced manufacturers. It is the combined performance of cyclotron and target in terms of available...

  15. SPECT og PET i neurobiologien

    DEFF Research Database (Denmark)

    Paulson, O B; Lassen, N A

    1997-01-01

    PET (positron emission tomography) and SPECT (single photon emission computed tomography) are isotopic methods in which the distribution is registered of radiolabelled tracers given in such small amounts that they are without effect on the organism or the organism's disposal of them. Thus, a series...

  16. Brain fluorodeoxyglucose PET in adrenoleukodystrophy.

    Science.gov (United States)

    Salsano, Ettore; Marotta, Giorgio; Manfredi, Valentina; Giovagnoli, Anna Rita; Farina, Laura; Savoiardo, Mario; Pareyson, Davide; Benti, Riccardo; Uziel, Graziella

    2014-09-09

    To investigate the cerebral glucose metabolism in subjects with X-linked adrenoleukodystrophy (X-ALD) by using brain [(18)F]-fluorodeoxyglucose PET (FDG-PET). Cross-sectional study in which 12 adults with various forms of X-ALD underwent clinical evaluation and brain MRI, followed by brain FDG-PET, neuropsychological assessment, and personality and psychopathology evaluation using the Symptom Checkist-90-Revised (SCL-90-R) and the Millon Clinical Multiaxial Inventory-III (MCMI-III). When compared to healthy control subjects (n = 27) by using Statistical Parametric Mapping 8 software, the patients with X-ALD-with or without brain MRI changes-showed a pattern of increased glucose metabolism in frontal lobes and reduced glucose metabolism in cerebellum and temporal lobe areas. On single case analysis by Scenium software, we found a similar pattern, with significant (p < 0.02) correlation between the degree of hypermetabolism in the frontal lobes of each patient and the corresponding X-ALD clinical scores. With respect to personality, we found that patients with X-ALD usually present with an obsessive-compulsive personality disorder on the MCMI-III, with significant (p < 0.05) correlation between glucose uptake in ventral striatum and severity of score on the obsessive-compulsive subscale. We examined cerebral glucose metabolism using FDG-PET in a cohort of patients with X-ALD and provided definite evidence that in X-ALD the analysis of brain glucose metabolism reveals abnormalities independent from morphologic and signal changes detected by MRI and related to clinical severity. Brain FDG-PET may be a useful neuroimaging technique for the characterization of X-ALD and possibly other leukodystrophies. © 2014 American Academy of Neurology.

  17. Dose Optimization in TOF-PET/MR Compared to TOF-PET/CT

    OpenAIRE

    Queiroz, Marcelo A; Gaspar Delso; Scott Wollenweber; Timothy Deller; Konstantinos Zeimpekis; Martin Huellner; Felipe de Galiza Barbosa; Gustav von Schulthess; Patrick Veit-Haibach

    2015-01-01

    PURPOSE: To evaluate the possible activity reduction in FDG-imaging in a Time-of-Flight (TOF) PET/MR, based on cross-evaluation of patient-based NECR (noise equivalent count rate) measurements in PET/CT, cross referencing with phantom-based NECR curves as well as initial evaluation of TOF-PET/MR with reduced activity. MATERIALS AND METHODS: A total of 75 consecutive patients were evaluated in this study. PET/CT imaging was performed on a PET/CT (time-of-flight (TOF) Discovery D 690 PET/CT)...

  18. Armazenamento de maçã 'gala' em atmosfera controlada com remoção de etileno Storage of 'gala' apple in controlled atmosphere with removal of ethylene

    Directory of Open Access Journals (Sweden)

    Auri Brackmann

    2003-08-01

    Full Text Available O objetivo deste trabalho foi avaliar o efeito de diferentes níveis de etileno na câmara sobre a manutenção da qualidade da maçã cv. Gala, durante o armazenamento em AC. O delineamento experimental utilizado foi inteiramente casualizado com quatro repetições e a unidade experimental composta por 50 frutos. Os tratamentos utilizados foram: >10µl L-1 (sem absorção; The objective purpose of this work was to evaluate the effect of different ethylene levels on the quality of cv. Gala apples during CA storage. The experimental design was completely randomized with 4 replications of 50 fruits. The treatments were: >10µl L-1 (without absorption; < 0.4µl L-1 and < 0.04µl L-1. After 8 month storage, at the chambers opening and after 7 days shelf life at 20ºC fruits with ethylene absorption had higher firmness and titratable acidity and lower rot and senescent breakdown incidence. There was no statistic difference between treatments for TSS. After 7 days shelf life ground color was greener on the fruits stored with ethylene absorption. Mealy fruits incidence was lower with ethylene absorption, at the chambers opening.

  19. Qualidade pós-colheita de frutos de tomate cv. Andréa tratados com etileno Postharvest quality of tomato fruits cv. Andréa treated with ethylene

    Directory of Open Access Journals (Sweden)

    Caroline Andreuccetti

    2007-03-01

    Full Text Available O tomate é uma das principais hortaliças cultivadas no Brasil e tratamentos que propiciem o controle do amadurecimento são extremamente desejáveis. Avaliou-se a qualidade pós-colheita de tomates tipo italiano tratados com etileno. Tomates 'Andréa' foram colhidos em campos de produção comercial no estádio verde-maduro, selecionados para presença de danos externos e classificados quanto ao tamanho e cor e posteriormente foram tratados com 100 µL L-1 de etileno. Os ensaios foram planejados com delineamento inteiramente casualizado em esquema fatorial com quatro tratamentos e quinze repetições (n=10. Após a aplicação, os frutos foram divididos em dois lotes. Um lote permaneceu a 20º±1ºC e outro foi mantido a 12,5º±1ºC, ambos sob umidade relativa 90±5%. Tomates do tratamento controle foram mantidos nas mesmas condições de temperatura e umidade relativa. Os frutos foram avaliados após cada mudança de estádio de amadurecimento para as seguintes variáveis: coloração externa (L*a*b*, perda de massa, sólidos solúveis totais, acidez titulável e teor de ácido ascórbico. A aplicação de etileno não influenciou de maneira significativa as variáveis químicas e físicas estudadas. Frutos armazenados à temperatura de 20ºC demonstraram maior porcentagem de perda de massa ao longo do amadurecimento, com média de 2,60%. A relação brix/acidez apresentou pouca variação entre os tratamentos avaliados. Frutos do tratamento controle e mantidos à temperatura de 20ºC apresentaram mudança de coloração mais rápida no início dos experimentos, não sendo observada posteriormente diferença significativa no desenvolvimento da cor dos tratamentos avaliados. O tratamento com etileno não acelerou de forma significativa o amadurecimento de tomates 'Andréa' armazenado sob as duas temperaturas estudadas.Tomatoes are one of the most important vegetable crops grown in Brazil and treatments that facilitate ripening control are

  20. Esterilização por óxido de etileno: I. Influência do meio de esporulação na resistência dos esporos de Bacillus subtilis var. niger

    Directory of Open Access Journals (Sweden)

    Terezinha de Jesus A. Pinto

    1992-12-01

    Full Text Available Tendo por meta a padronização das variáveis influenciando a resistência de esporos empregados no controle do processo esterilizante por óxido de etileno, foram obtidos esporos de Bacillus subtilis var. niger, em meio sólido e líquido sintético de esporulação. Tais esporos, após padronização quantitativa dos 12 lotes obtidos, foram submetidos a exposições subletais como bioindicadores, tendo o papel como suporte. Construiu-se, então, a curva de letalidade característica de cada lote. A análise estatística empregada não evidenciou diferenças entre resistência dos 10 lotes obtidos em meio sólido e os 2 em meio líquido sintético, ressaltando-se a vantagem quanto ao rendimento que caracterizou a primeira metodologia.

  1. Esterilização por óxido de etileno: I. Influência do meio de esporulação na resistência dos esporos de Bacillus subtilis var. niger

    Directory of Open Access Journals (Sweden)

    Pinto Terezinha de Jesus A.

    1992-01-01

    Full Text Available Tendo por meta a padronização das variáveis influenciando a resistência de esporos empregados no controle do processo esterilizante por óxido de etileno, foram obtidos esporos de Bacillus subtilis var. niger, em meio sólido e líquido sintético de esporulação. Tais esporos, após padronização quantitativa dos 12 lotes obtidos, foram submetidos a exposições subletais como bioindicadores, tendo o papel como suporte. Construiu-se, então, a curva de letalidade característica de cada lote. A análise estatística empregada não evidenciou diferenças entre resistência dos 10 lotes obtidos em meio sólido e os 2 em meio líquido sintético, ressaltando-se a vantagem quanto ao rendimento que caracterizou a primeira metodologia.

  2. Influência de estabilizantes na degradação foto-oxidativa de filmes de compósitos de SWy-1/poli(óxido de etileno

    Directory of Open Access Journals (Sweden)

    Patrícia Coelho Lombardo

    2015-02-01

    Full Text Available Compósitos de poli(óxido de etileno (PEO com argila montmorilonita SWy-1 e estabilizantes (2-hidroxibenzofenona e tinuvin 770 foram preparados pelo método de intercalação em solução. Os filmes obtidos foram expostos a irradiação UV, e os produtos da fotodegradação foram monitorados por FTIR (Fourier Transform Infrared Spectroscopy, ou Espectroscopia no infravermelho por transformada de Fourier e SEC (Size Exclusion Chromatography, ou cromatografia de exclusão por tamanho. O PEO puro apresentou maior coeficiente de degradação, kd, comparado com as demais amostras. O sistema que apresentou o menor valor para o coeficiente de degradação (kd = 1,9×10–6 mol g–1 h-1 foi o compósito de PEO/5%SWy-1 com 0,25% de tinuvin 770. Nesse caso, a estabilização da matriz de PEO pode ser atribuída à argila juntamente com o tinuvin 770. A argila dispersa e absorve a irradiação UV, e o tinuvin age como estabilizante do tipo HALS (do inglês hindered amine light stabilizer, ou estabilizantes à luz tipo aminas impedidas.

  3. Pet Ownership by Elderly People: Two New Issues.

    Science.gov (United States)

    Smith, David W. E.; And Others

    1992-01-01

    Examined two issues of pet ownership in mail questionnaire and interview survey of 1,595 older adults over age 60, 377 of whom had a pet. Found evidence that pets were important determinant of housing choice. Many elderly pet owners had made no arrangements for pet if they predecease it or become unable to care for it. (Author/NB)

  4. Comparison of integrated whole-body PET/MR and PET/CT: Is PET/MR alternative to PET/CT in routine clinical oncology?

    Science.gov (United States)

    Ishii, Shirou; Shimao, Daisuke; Hara, Takamitsu; Miyajima, Masayuki; Kikuchi, Ken; Takawa, Masashi; Kumamoto, Kensuke; Ito, Hiroshi; Shishido, Fumio

    2016-04-01

    To compare the diagnostic accuracy of whole-body PET/CT and integrated PET/MR in relation to the total scan time durations. One hundred and twenty-three (123) patients (40 males and 83 females; mean age 59.6 years; range 20-83 years) with confirmed primary cancer and clinical suspicion of metastatic disease underwent whole-body 18F-FDG-PET/CT and 18F-FDG-PET/MR. Data acquisition was done after intravenous administration of 110-301 MBq radioactivity of 18F-FDG, and PET/MR data were acquired after the PET/CT data acquisition. The mean uptake times for PET/CT and PET/MR acquisition were 68.0 ± 8.0 and 98.0 ± 14 min, respectively. Total scan time was 20.0 and 25.0 min for whole-body PET/CT and PET/MR imaging. The reconstructed PET/CT and PET/MR data detected 333/355 (93.8 %) common lesions in 111/123 (90.2 %) patients. PET/CT and PET/MR alone detected 348/355 and 340/355 lesions, respectively. No significant (p = 0.08) difference was observed for the overall detection efficiency between the two techniques. On the other hand, a significant difference was observed between the two techniques for the detection of lung (p = 0.003) and cerebrospinal (p = 0.007) lesions. The 15 lesions identified by PET/CT only included 8 lung, 3 lymph nodes, 2 bone, and 1 each of peritoneal and adrenal gland lesions. On the other hand, 7 (6 brain metastatic lesions and 1 bone lesion) were identified by PET/MR only. Integrated PET/MR is a feasible whole-body imaging modality and may score better than PET/CT for the detection of brain metastases. To further prove diagnostic utility, this technique requires further clinical validation.

  5. Basic study of entire whole-body PET scanners based on the OpenPET geometry

    Energy Technology Data Exchange (ETDEWEB)

    Yoshida, Eiji, E-mail: rush@nirs.go.j [National Institute of Radiological Sciences, 4-9-1 Inage-ku, Chiba 263-8555 (Japan); Yamaya, Taiga; Nishikido, Fumihiko; Inadama, Naoko; Murayama, Hideo [National Institute of Radiological Sciences, 4-9-1 Inage-ku, Chiba 263-8555 (Japan)

    2010-09-21

    A conventional PET scanner has a 15-25 cm axial field-of-view (FOV) and images a whole body using about six bed positions. An OpenPET geometry can extend the axial FOV with a limited number of detectors. The entire whole-body PET scanner must be able to process a large amount of data effectively. In this work, we study feasibility of the fully 3D entire whole-body PET scanner using the GATE simulation. The OpenPET has 12 block detector rings with the ring diameter of 840 mm and each block detector ring consists of 48 depth-of-interaction (DOI) detectors. The OpenPET has the axial length of 895.95 mm with five parts of 58.95 mm open gaps. The OpenPET has higher single data loss than a conventional PET scanner at grouping circuits. NECR of the OpenPET decreases by single data loss. But single data loss is mitigated by separating the axially arranged detector into two parts. Also, multiple coincidences are found to be important for the entire whole-body PET scanner. The entire whole-body PET scanner with the OpenPET geometry promises to provide a large axial FOV with the open space and to have sufficient performance values. But single data loss at the grouping circuits and multiple coincidences are limited to the peak noise equivalent count rate (NECR) for the entire whole-body PET scanner.

  6. Childhood Attachment to Pets: Associations between Pet Attachment, Attitudes to Animals, Compassion, and Humane Behaviour

    Directory of Open Access Journals (Sweden)

    Roxanne D. Hawkins

    2017-05-01

    Full Text Available Attachment to pets has an important role in children’s social, emotional, and cognitive development, mental health, well-being, and quality of life. This study examined associations between childhood attachment to pets and caring and friendship behaviour, compassion, and attitudes towards animals. This study also examined socio-demographic differences, particularly pet ownership and pet type. A self-report survey of over one thousand 7 to 12 year-olds in Scotland, UK, revealed that the majority of children are strongly attached to their pets, but attachment scores differ depending on pet type and child gender. Analysis revealed that attachment to pets is facilitated by compassion and caring and pet-directed friendship behaviours and that attachment to pets significantly predicts positive attitudes towards animals. The findings have implications for the promotion of prosocial and humane behaviour. Encouraging children to participate in pet care behaviour may promote attachment between children and their pet, which in turn may have a range of positive outcomes for both children (such as reduced aggression, better well-being, and quality of life and pets (such as humane treatment. This study enhances our understanding of childhood pet attachment and has implications for humane education and promoting secure emotional attachments in childhood.

  7. PET/MRI and PET/CT in advanced gynaecological tumours: initial experience and comparison

    Energy Technology Data Exchange (ETDEWEB)

    Queiroz, Marcelo A.; Schulthess, Gustav von; Veit-Haibach, Patrick [University Hospital Zurich, Department Medical Radiology, Nuclear Medicine, Zurich (Switzerland); University Hospital Zurich, Department Medical Radiology, Diagnostic and Interventional Radiology, Zurich (Switzerland); University of Zurich, Zurich (Switzerland); Kubik-Huch, Rahel A.; Freiwald-Chilla, Bianka [Kantonsspital Baden AG, Department of Radiology, Baden (Switzerland); Hauser, Nik [Kantonsspital Baden AG, Department of Gynaecology, Baden (Switzerland); Froehlich, Johannes M. [Guerbet AG, Zurich (Switzerland)

    2015-08-15

    To compare the diagnostic accuracy of PET/MRI and PET/CT for staging and re-staging advanced gynaecological cancer patients as well as identify the potential benefits of each method in such a population. Twenty-six patients with suspicious or proven advanced gynaecological cancer (12 ovarian, seven cervical, one vulvar and four endometrial tumours, one uterine metastasis, and one primary peritoneal cancer) underwent whole-body imaging with a sequential trimodality PET/CT/MR system. Images were analysed regarding primary tumour detection and delineation, loco-regional lymph node staging, and abdominal/extra-abdominal distant metastasis detection (last only by PET/CT). Eighteen (69.2 %) patients underwent PET/MRI for primary staging and eight patients (30.8 %) for re-staging their gynaecological malignancies. For primary tumour delineation, PET/MRI accuracy was statistically superior to PET/CT (p < 0.001). Among the different types of cancer, PET/MRI presented better tumour delineation mainly for cervical (6/7) and endometrial (2/3) cancers. PET/MRI for local evaluation as well as PET/CT for extra-abdominal metastases had therapeutic consequences in three and one patients, respectively. PET/CT detected 12 extra-abdominal distant metastases in 26 patients. PET/MRI is superior to PET/CT for primary tumour delineation. No differences were found in detection of regional lymph node involvement and abdominal metastases detection. (orig.)

  8. Childhood Attachment to Pets: Associations between Pet Attachment, Attitudes to Animals, Compassion, and Humane Behaviour.

    Science.gov (United States)

    Hawkins, Roxanne D; Williams, Joanne M; Scottish Society For The Prevention Of Cruelty To Animals Scottish Spca

    2017-05-06

    Attachment to pets has an important role in children's social, emotional, and cognitive development, mental health, well-being, and quality of life. This study examined associations between childhood attachment to pets and caring and friendship behaviour, compassion, and attitudes towards animals. This study also examined socio-demographic differences, particularly pet ownership and pet type. A self-report survey of over one thousand 7 to 12 year-olds in Scotland, UK, revealed that the majority of children are strongly attached to their pets, but attachment scores differ depending on pet type and child gender. Analysis revealed that attachment to pets is facilitated by compassion and caring and pet-directed friendship behaviours and that attachment to pets significantly predicts positive attitudes towards animals. The findings have implications for the promotion of prosocial and humane behaviour. Encouraging children to participate in pet care behaviour may promote attachment between children and their pet, which in turn may have a range of positive outcomes for both children (such as reduced aggression, better well-being, and quality of life) and pets (such as humane treatment). This study enhances our understanding of childhood pet attachment and has implications for humane education and promoting secure emotional attachments in childhood.

  9. Role of Cardiac PET in Clinical Practice.

    Science.gov (United States)

    Salata, Brian M; Singh, Parmanand

    2017-11-09

    Early identification of atherosclerosis and at-risk lesions plays a critical role in reducing the burden of cardiovascular disease. While invasive coronary angiography serves as the gold standard for diagnosing coronary artery disease, non-invasive imaging techniques provide visualization of both anatomical and functional atherosclerotic processes prior to clinical presentation. The development of cardiac positron emission tomography (PET) has greatly enhanced our capability to diagnose and treat patients with early stages of atherosclerosis. Cardiac PET is a powerful, versatile non-invasive diagnostic tool with utility in the identification of high-risk plaques, myocardial perfusion defects, and viable myocardial tissue. Cardiac PET allows for comparisons of myocardial function both at time of rest and stress, providing accurate assessments of both myocardial perfusion and viability. Furthermore, novel PET techniques with unique radiotracers yield clinically relevant data on high-risk plaques in active progressive atherosclerosis. While PET exercise stress tests were previously difficult to perform given short radiotracer half-life, the development of the novel radiotracer Flurpiridaz F-18 provides a promising future for PET exercise stress imaging. In addition, hybrid imaging with computed tomography angiography (CTA) and cardiac magnetic resonance (CMR) provides integration of cardiac function and structure. In this review article, we discuss the principles of cardiac PET, the clinical applications of PET in diagnosing and prognosticating patients at risk for future cardiovascular events, compare PET with other non-invasive cardiac imaging modalities, and discuss future applications of PET in CVD evaluation and management.

  10. PET/MR: a paradigm shift

    Science.gov (United States)

    Fürst, Sebastian; Schwaiger, Markus

    2013-01-01

    Abstract More than a decade ago, multimodality imaging was introduced into clinical routine with the development of the positron emission tomography (PET)/computed tomography (CT) technique. Since then, PET/CT has been widely accepted in clinical imaging and has emerged as one of the main cancer imaging modalities. With the recent development of combined PET/magnetic resonance (MR) systems for clinical use, a promising new hybrid imaging modality is now becoming increasingly available. The combination of functional information delivered by PET with the morphologic and functional imaging of MR imaging (e.g., diffusion-weighted imaging, dynamic contrast-enhanced MR imaging and MR spectroscopy) offers exciting possibilities for clinical applications as well as basic research. However, the differences between CT and MR imaging are fundamental. This also leads to distinct differences between PET/CT and PET/MR not only regarding image interpretation but also concerning data acquisition, data processing and image reconstruction. This article provides an overview of the principal differences between PET/CT and PET/MR in terms of scanner design and technology, attenuation correction, speed, acquisition protocols, radiation exposure and safety aspects. PET/MR is expected to show advantages over PET/CT in clinical applications in which MR is known to be superior to CT due to its high intrinsic soft tissue contrast. However, as of now, only assumptions can be made about the future clinical role of PET/MR, as data about the performance of PET/MR in the clinical setting are still limited. The possible future clinical use of PET/MR in oncology, neurology and neurooncology, cardiology and imaging of inflammation is discussed. PMID:23446110

  11. PET Performance Evaluation of an MR-Compatible PET Insert

    Science.gov (United States)

    Wu, Yibao; Catana, Ciprian; Farrell, Richard; Dokhale, Purushottam A.; Shah, Kanai S.; Qi, Jinyi; Cherry, Simon R.

    2009-06-01

    A magnetic resonance (MR) compatible positron emission tomography (PET) insert has been developed in our laboratory for simultaneous small animal PET/MR imaging. This system is based on lutetium oxyorthosilicate (LSO) scintillator arrays with position-sensitive avalanche photodiode (PSAPD) photodetectors. The PET performance of this insert has been measured. The average reconstructed image spatial resolution was 1.51 mm. The sensitivity at the center of the field of view (CFOV) was 0.35%, which is comparable to the simulation predictions of 0.40%. The average photopeak energy resolution was 25%. The scatter fraction inside the MRI scanner with a line source was 12% (with a mouse-sized phantom and standard 35 mm Bruker 1 H RF coil), 7% (with RF coil only) and 5% (without phantom or RF coil) for an energy window of 350-650 keV. The front-end electronics had a dead time of 390 ns, and a trigger extension dead time of 7.32 mus that degraded counting rate performance for injected doses above 0.75 mCi (28 MBq). The peak noise-equivalent count rate (NECR) of 1.27 kcps was achieved at 290 muCi (10.7 MBq). The system showed good imaging performance inside a 7-T animal MRI system; however improvements in data acquisition electronics and reduction of the coincidence timing window are needed to realize improved NECR performance.

  12. Use of polyethylene bags and ethylene absorption on refrigerated transport of ‘Gala’ apple fruit/ Uso de filmes de polietileno e absorção de etileno para o transporte refrigerado de maçã ‘Gala’

    Directory of Open Access Journals (Sweden)

    Anderson Machado de Mello

    2006-06-01

    Full Text Available The objective of this experiment was to evaluate the gaseous composition and quality maintenance of ‘Gala’ apples, stored within polyethylene (PE bags of different thickness combined with ethylene absorption, during refrigerated transport. The treatments evaluated were combinations of two PE film thickness [high density polyethylene (HDPE of 7µm and low density polyethylene (LDPE of 20µm] with different number of ethylene absorbents (potassium permanganate per bag (0, 1 and 3. Each experimental unity contained 18kg of fruits previously stored at 0.5°C during 1 month. After this period fruits were wrapped with the films and packed in cadboard boxes, being submitted during 15 days at 4°C, simulating refrigerated transport plus 3 days of shelf-life at 20°C. Lower levels of O2 and ethylene and higher of CO2 were observed within LDPE bags of 20µm than in HDPE bags of 7µm. Moreover, the use of ethylene absorbents reduced the ethylene level within bags. However, due to the low storage time (15 days and fruit ripeness at the packaging, the reduction of ethylene levels did not show significant effect on fruit quality.Conduziu-se um experimento com o objetivo de avaliar o efeito do uso de filmes de polietileno (PE de diferentes espessuras e o uso de sachês absorvedores de etileno sobre a composição gasosa presente nas embalagens e sobre a qualidade da maçã ‘Gala’, durante o período de transporte sob refrigeração. Os tratamentos foram obtidos pela combinação de duas espessuras de filmes de polietileno [polietileno de alta densidade (PEAD de 7mm e polietileno de baixa densidade (PEBD de 20mm] e de diferentes quantidades de sachês absorvedores de etileno (permanganato de potássio por embalagem (0, 1 e 3 sachês. Cada unidade experimental constituiu-se de 18kg de frutos, que haviam sido previamente armazenados a 0,5°C por um mês. Após este período, os frutos foram embalados nos filmes, acondicionados em caixas de papelão e

  13. FDG PET and PET/CT: EANM procedure guidelines for tumour PET imaging: version 1.0

    DEFF Research Database (Denmark)

    Boellaard, Ronald; O'Doherty, Mike J; Weber, Wolfgang A

    2010-01-01

    The aim of this guideline is to provide a minimum standard for the acquisition and interpretation of PET and PET/CT scans with [18F]-fluorodeoxyglucose (FDG). This guideline will therefore address general information about[18F]-fluorodeoxyglucose (FDG) positron emission tomography......-computed tomography (PET/CT) and is provided to help the physician and physicist to assist to carrying out,interpret, and document quantitative FDG PET/CT examinations,but will concentrate on the optimisation of diagnostic quality and quantitative information....

  14. PET/MRI in cancer patients

    DEFF Research Database (Denmark)

    Kjær, Andreas; Loft, Annika; Law, Ian

    2013-01-01

    described include brain tumors, pediatric oncology as well as lung, abdominal and pelvic cancer. In general the cases show that PET/MRI performs well in all these types of cancer when compared to PET/CT. However, future large-scale clinical studies are needed to establish when to use PET/MRI. We envision...... that PET/MRI in oncology will prove to become a valuable addition to PET/CT in diagnosing, tailoring and monitoring cancer therapy in selected patient populations.......Combined PET/MRI systems are now commercially available and are expected to change the medical imaging field by providing combined anato-metabolic image information. We believe this will be of particular relevance in imaging of cancer patients. At the Department of Clinical Physiology, Nuclear...

  15. PET/MRI in cancer patients

    DEFF Research Database (Denmark)

    Kjær, Andreas; Loft, Annika; Law, Ian

    2013-01-01

    Combined PET/MRI systems are now commercially available and are expected to change the medical imaging field by providing combined anato-metabolic image information. We believe this will be of particular relevance in imaging of cancer patients. At the Department of Clinical Physiology, Nuclear...... described include brain tumors, pediatric oncology as well as lung, abdominal and pelvic cancer. In general the cases show that PET/MRI performs well in all these types of cancer when compared to PET/CT. However, future large-scale clinical studies are needed to establish when to use PET/MRI. We envision...... that PET/MRI in oncology will prove to become a valuable addition to PET/CT in diagnosing, tailoring and monitoring cancer therapy in selected patient populations....

  16. PET/MR Outperforms PET/CT in Suspected Occult Tumors.

    Science.gov (United States)

    Sekine, Tetsuro; Barbosa, Felipe de Galiza; Sah, Bert-Ram; Mader, Cäcilia E; Delso, Gaspar; Burger, Irene A; Stolzmann, Paul; Ter Voert, Edwin E; von Schulthess, Gustav K; Veit-Haibach, Patrick; Huellner, Martin W

    2017-02-01

    To compare the diagnostic accuracy of PET/MR and PET/CT in patients with suspected occult primary tumors. This prospective study was approved by the institutional review board. Sequential PET/CT-MR was performed in 43 patients (22 male subjects; median age, 58 years; range, 20-86 years) referred for suspected occult primary tumors. Patients were assessed with PET/CT and PET/MR for the presence of a primary tumor, lymph node metastases, and distant metastases. Wilcoxon signed-rank test was performed to compare the diagnostic accuracy of PET/CT and PET/MR. According to the standard of reference, a primary lesion was found in 14 patients. In 16 patients, the primary lesion remained occult. In the remaining 13 patients, lesions proved to be benign. PET/MR was superior to PET/CT for primary tumor detection (sensitivity/specificity, 0.85/0.97 vs 0.69/0.73; P = 0.020) and comparable to PET/CT for the detection of lymph node metastases (sensitivity/specificity, 0.93/1.00 vs 0.93/0.93; P = 0.157) and distant metastases (sensitivity/specificity, 1.00/0.97 vs 0.82/1.00; P = 0.564). PET/CT tended to misclassify physiologic FDG uptake as malignancy compared with PET/MR (8 patients vs 1 patient). PET/MR outperforms PET/CT in the workup of suspected occult malignancies. PET/MR may replace PET/CT to improve clinical workflow.

  17. PET/MR in the Assessment of Pediatric Histiocytoses: A Comparison to PET/CT.

    Science.gov (United States)

    Sher, Andrew C; Orth, Robert; McClain, Kenneth; Allen, Carl; Hayatghaibi, Shireen; Seghers, Victor

    2017-08-01

    The aim of this study was to analyze the feasibility and diagnostic performance of F-FDG PET/MR compared with F-FDG PET/CT in a cohort of pediatric histiocytosis patients with regard to image quality, lesion detection, and FDG quantification. Children with a diagnosis of Langerhans cell histiocytosis or Rosai-Dorfman disease were prospectively recruited. Seventeen PET/CT and PET/MR examinations were performed on 9 patients (mean age, 6.2 years) following a single-injection dual-imaging protocol. The indication was Langerhans cell histiocytosis in 10 examinations and Rosai-Dorfman disease in 7 examinations. The anonymized data were evaluated for image quality and lesion detection. SUV quantification of each lesion was compared between modalities. All PET/MR examinations had good or excellent image quality and were deemed clinically acceptable. There was substantial agreement of PET image quality among readers of PET/MR images. Per patient, PET/MR and PET/CT had complete concordance in identifying active disease. PET/MRI correctly classified 74 (96%) of 77 foci of disease identified on PET/CT. The per-lesion maximum SUVs were strongly correlated between modalities with a Spearman correlation coefficient of 0.73 (P PET/MR is clinically feasible in pediatric patients with a histiocytic disease. PET/MR demonstrates comparable image quality and lesion detection to PET/CT while maintaining strongly correlated quantitative performance. Given the significant radiation dose savings, PET/MR represents an appealing alternative to PET/CT in the care of children with histiocytic disorders.

  18. Pet Ownership and Evacuation Prior to Hurricane Irene

    Directory of Open Access Journals (Sweden)

    Nick Rohrbaugh

    2012-09-01

    Full Text Available Pet ownership has historically been one of the biggest risk factors for evacuation failure prior to natural disasters. The forced abandonment of pets during Hurricane Katrina in 2005 made national headlines and led to the passage of the Pet Evacuation and Transportation Standards Act (PETS, 2006 which mandated local authorities to plan for companion animal evacuation. Hurricane Irene hit the East Coast of the United States in 2011, providing an excellent opportunity to examine the impact of the PETS legislation on frequency and ease of evacuation among pet owners and non-pet owners. Ninety pet owners and 27 non-pet owners who lived in mandatory evacuation zones completed questionnaires assessing their experiences during the hurricane and symptoms of depression, PTSD, dissociative experiences, and acute stress. Pet ownership was not found to be a statistical risk factor for evacuation failure. However, many pet owners who failed to evacuate continue to cite pet related reasons.

  19. Pet Ownership and Evacuation Prior to Hurricane Irene.

    Science.gov (United States)

    Hunt, Melissa G; Bogue, Kelsey; Rohrbaugh, Nick

    2012-09-28

    Pet ownership has historically been one of the biggest risk factors for evacuation failure prior to natural disasters. The forced abandonment of pets during Hurricane Katrina in 2005 made national headlines and led to the passage of the Pet Evacuation and Transportation Standards Act (PETS, 2006) which mandated local authorities to plan for companion animal evacuation. Hurricane Irene hit the East Coast of the United States in 2011, providing an excellent opportunity to examine the impact of the PETS legislation on frequency and ease of evacuation among pet owners and non-pet owners. Ninety pet owners and 27 non-pet owners who lived in mandatory evacuation zones completed questionnaires assessing their experiences during the hurricane and symptoms of depression, PTSD, dissociative experiences, and acute stress. Pet ownership was not found to be a statistical risk factor for evacuation failure. However, many pet owners who failed to evacuate continue to cite pet related reasons.

  20. Know the Risks of Feeding Raw Food to Your Pets

    Science.gov (United States)

    ... one factor that should be considered when selecting diets for your pet.” June 30, 2014 back to top Related Consumer Updates Animal & Veterinary Avoid the Dangers of Raw Pet Food Tips for Safe Handling of Pet Food and ...

  1. Pet Store Loyalty in Malaysia

    OpenAIRE

    Leong, Yuen Yee

    2010-01-01

    Loyalty is open studied topic within the retailing and marketing discipline. A strong and profitable base of loyal customers is an asset to any organization, and is one of the epitomes of success for a company. The flourishing of large, specialty niche retailers like Starbucks, Victoria Secret and Barnes & Noble are stellar success stories that thrive on their troop of staunch followers. Pet retailing is a niche market which has its own interesting market characteristics. The emergence of ...

  2. Critical Care of Pet Birds.

    Science.gov (United States)

    Jenkins, Jeffrey Rowe

    2016-05-01

    Successful care of the critical pet bird patient is dependent on preparation and planning and begins with the veterinarian and hospital staff. An understanding of avian physiology and pathophysiology is key. Physical preparation of the hospital or clinic includes proper equipment and understanding of the procedures necessary to provide therapeutic and supportive care to the avian patient. An overview of patient intake and assessment, intensive care environment, and fluid therapy is included. Copyright © 2016 Elsevier Inc. All rights reserved.

  3. The AX-PET project Demonstration of a high resolution axial 3D PET

    CERN Document Server

    Bolle, E; Casella, C; Chesi, E; Clinthorne, N; Cochran, E; De Leo, R; Dissertori, G; Djambazov, G; Fanti, V; Honscheid, K; Huh, S; Johnson, I; Joram, C; Kagan, H; Lustermann, W; Meddi, F; Nappi, E; Nessi-Tedaldi, F; Oliver, J F; Pauss, P; Rafecas, M; Renker, D; Rudge, A; Schinzel, D; Schneider, T; Seguinot, J; Smith, S; Solevi, P; Stapnes, S; Weilhammer, P

    2010-01-01

    The AX-PET is a new geometrical concept for a high resolution 3D PET scanner, based on matrices of axially oriented LYSO crystals interleaved by stacks of WLS, both individually read out by G-APDs. A PET demonstrator, based on two detector modules used in coincidence, is currently under construction.

  4. Processing and characterization of extruded PET and its r-PET and ...

    Indian Academy of Sciences (India)

    of r-PET and r-PET+ MWCNT fillers was obtained by the precipitation method using TFA as a solvent and acetone as an antisolvent. The samples before spin coating were extruded and for comparison, a film of non-extruded PET was also prepared. Structural studies by Fourier transform infrared and X-ray diffraction show ...

  5. Evacuating People and Their Pets: Older Floridians' Need for and Proximity to Pet-Friendly Shelters.

    Science.gov (United States)

    Douglas, Rachel; Kocatepe, Ayberk; Barrett, Anne E; Ozguven, Eren Erman; Gumber, Clayton

    2017-10-04

    Pets influence evacuation decisions, but little is known about pet-friendly emergency shelters' availability or older adults' need for them. Our study addresses this issue, focusing on the most densely populated area of Florida (Miami-Dade)-the state with the oldest population and greatest hurricane susceptibility. We use Geographic Information Systems (GIS)-based methodology to identify the shortest paths to pet-friendly shelters, based on distance and congested and uncongested travel times-taking into account the older population's spatial distribution. Logistic regression models using the 2013 American Housing Survey's Disaster Planning Module examine anticipated shelter use as a function of pet ownership and requiring pet evacuation assistance. Thirty-four percent of older adults in the Miami-Dade area have pets-35% of whom report needing pet evacuation assistance. However, GIS accessibility measures show that travel time factors are likely to impede older adults' use of the area's few pet-friendly shelters. Logistic regression results reveal that pet owners are less likely to report anticipating shelter use; however, the opposite holds for pet owners reporting they would need help evacuating their pets-they anticipate using shelters. High pet shelter need coupled with low availability exacerbates older adults' heightened vulnerability during Florida's hurricane season.

  6. F-18-FLT PET for visualization of laryngeal cancer : Comparison with F-18-FDG PET

    NARCIS (Netherlands)

    Cobben, DCP; van der Laan, BFAM; Maas, B; Vaalburg, W; Suurmeijer, AJH; Hoekstra, HJ; Jager, PL; Elsinga, PH

    The feasibility of F-18-3'-fluoro-3'-deoxy-L-thymidine PET (FLT PET) for detecting laryngeal cancer was investigated and compared with F-18-FDG PET. Methods: Eleven patients diagnosed with or strongly suspected of having recurrent laryngeal cancer and 10 patients with histologically proven primary

  7. Processing and characterization of extruded PET and its r-PET and ...

    Indian Academy of Sciences (India)

    The objective of the present study was basic understanding of the formation of thin film morphology by spin coating using reorganized polyethylene terephthalate (r-PET) and multiwalled carbon nanotubes (MWCNTs) as fillers in PET. A study of the correlation between physical properties of the PET films and its surface ...

  8. Indução de calos e regeneração de embriões em anteras de Coffea arabica L. por nitrato de prata e etileno Callus induction and embryo regeneration in Coffea arabica L. anthers by silver nitrate and ethylene

    Directory of Open Access Journals (Sweden)

    Adelaide Siqueira Silva

    2011-12-01

    Full Text Available O melhoramento genético do cafeeiro por métodos convencionais é um processo demorado para aquisição de uma nova cultivar. Através da cultura de anteras podem-se obter linhagens homozigóticas rapidamente, oriundas de dihaplóides. O objetivo foi utilizar na cultura de anteras na cv. Catuaí Vermelho 99 de Coffea arabica L., nitrato de prata (AgNO3 e etileno para induzir a formação de calos e regenerar plântulas dihaplóides. As anteras foram inoculadas em meio MS acrescido de 2 mg L-1 de 2,4-D com e sem AgNO3 (5 mg L-1, juntamente com etileno por diferentes dias: (testemunha; 2; 4; 6, e 8. Ao final de 12 dias, estas foram transferidas para o meio de regeneração, acrescido de 0,108 mg L-1 de cinetina. Foi observada uma oxidação e intumescimento maior nos primeiros dias de inoculação em exposição ao etileno, e a cv. Catuaí Vermelho 99 respondeu a formação de calos e também a embriogênese direta na presença do etileno.The genetic breeding of coffee by conventional methods to obtain new cultivars is time-consuming. Anther culture can yield homozygous lines quickly from bi-haploids. This study used anther cultures of Coffea arabica L. cv. Catuaí Vermelho 99, and tested the effect of silver nitrate (AgNO3 and ethylene in callus-formation induction and bi-haploid seedling regeneration. The anthers were inoculated in MS to which 2 mg L-1 2,4-D had been added with AgNO3 (5 mg L-1 together with ethylene being introduced or not, for different periods (the control, 2, 4, 6, and 8 days. At the end of 12 days, the anthers were transferred to the regeneration medium, to which 0.108 mg L-1 kinetin had been added. Greater oxidation and intumescence were observed in the first days after exposure to ethylene; the cultivar Catuaí Vermelho 99 responded to callus formation and also direct embryogenesis in the presence of ethylene.

  9. Bacterial Zoonoses Transmitted by Household Pets

    DEFF Research Database (Denmark)

    Damborg, Peter Panduro; Broens, E.M.; Chomel, B.B.

    2016-01-01

    with urine), and campylobacteriosis and salmonellosis (faecal–oral ingestion). Antimicrobial resistance was also included due to the recent emergence of multidrug-resistant bacteria of zoonotic potential in dogs and cats. There is a general lack of data on pathogen prevalence in the relevant pet population...... to estimate the burden of human disease attributable to pets and to identify risk behaviours facilitating transmission, and (3) education of those in charge of pets, animal caretakers, veterinarians and human medical healthcare practitioners on the potential zoonotic risks associated with exposure to pets...

  10. PET-Computed Tomography in Veterinary Medicine.

    Science.gov (United States)

    Randall, Elissa K

    2016-05-01

    PET/CT is an advanced imaging modality that is becoming more commonly used in veterinary medicine. It is most commonly used to image patients with cancer, and the most frequently used radiopharmaceutical is F-18 FDG. F-18 FDG is a glucose analog that highlights areas of increased glucose metabolism on the PET images. CT images provide excellent anatomic depiction and aid in interpretation of the PET data. Many types of cancer are hypermetabolic on PET/CT scans, but normal structures and areas of inflammation are also hypermetabolic, so knowledge of normal imaging and cytologic or histopathologic evaluation of lesions is essential. Copyright © 2016 Elsevier Inc. All rights reserved.

  11. Pet food safety: the roles of government, manufacturers, and veterinarians.

    Science.gov (United States)

    Eirmann, Laura; Cowell, Christopher; Thompson, Larry

    2012-01-01

    Food safety is of concern for both human and companion animal health. Government agencies, pet food manufacturers, and veterinarians play crucial roles in ensuring the safety of pet food and safeguarding pets and their owners. Recent legislation will increase the governmental role in regulating pet food and will affect many manufacturers. Veterinarians continue to play a vital role by recognizing and reporting pet food safety issues and by educating clients on matters related to pet food safety.

  12. Musculoskeletal imaging using fluoride PET.

    Science.gov (United States)

    Fischer, Dorothee Rita

    2013-11-01

    The convenience of (18)F-fluoride imaging is undeniable both because of its favorable tracer and because of its technical characteristics, including high image quality and short examination times leading to increased patient comfort. Depending on the activity administered, the radiation dose to patients is about comparable to higher using (18)F-fluoride for bone imaging compared with conventional scintigraphy using 99mTc-methylene diphosphonate. In times of molybdenum shortage, (18)F-fluoride represents a good alternative to 99mTc-based bone tracers. Besides malignant skeletal disease(18)F-fluoride PET/CT has in the last decade been investigated in a variety of non-oncologic musculoskeletal disorders of all parts of the skeleton. Studies included imaging of the skull with a special focus on bisphosphonate-induced osteonecrosis of the jaw in patients treated with bisphosphonates due to benign or malignant bone changes. Further studies evaluated the appendicular skeleton with emphasis on postsurgical changes including patients after knee and hip surgery and patients having received bone grafts of their limbs. Also, therapeutic effect of (18)F-fluoride PET/CT on patients with unclear foot pain was investigated. Finally imaging of the axial skeleton was analyzed including patients with ankylosing spondylitis and with Paget disease as well as patients after spine surgery including assessment of cage incorporation after cervical and lumbar spine fusion surgery. Furthermore, children suspected of child abuse as well as young patients with back pain were investigated by either (18)F-fluoride PET or PET/CT. Regarding its favorable technical aspects as well as study results presented, it is imaginable that (18)F-fluoride PET/(CT) will be increasingly used for non-oncologic musculoskeletal imaging in the future either as an adjunct or alternative to so far established imaging modalities and seems to be promising regarding decision making in the therapeutic management of

  13. Colorectal cancer staging: comparison of whole-body PET/CT and PET/MR.

    Science.gov (United States)

    Catalano, Onofrio A; Coutinho, Artur M; Sahani, Dushyant V; Vangel, Mark G; Gee, Michael S; Hahn, Peter F; Witzel, Thomas; Soricelli, Andrea; Salvatore, Marco; Catana, Ciprian; Mahmood, Umar; Rosen, Bruce R; Gervais, Debra

    2017-04-01

    Correct staging is imperative for colorectal cancer (CRC) since it influences both prognosis and management. Several imaging methods are used for this purpose, with variable performance. Positron emission tomography-magnetic resonance (PET/MR) is an innovative imaging technique recently employed for clinical application. The present study was undertaken to compare the staging accuracy of whole-body positron emission tomography-computed tomography (PET/CT) with whole-body PET/MR in patients with both newly diagnosed and treated colorectal cancer. Twenty-six patients, who underwent same day whole-body (WB) PET/CT and WB-PET/MR, were evaluated. PET/CT and PET/MR studies were interpreted by consensus by a radiologist and a nuclear medicine physician. Correlations with prior imaging and follow-up studies were used as the reference standard. Correct staging was compared between methods using McNemar's Chi square test. The two methods were in agreement and correct for 18/26 (69%) patients, and in agreement and incorrect for one patient (3.8%). PET/MR and PET/CT stages for the remaining 7/26 patients (27%) were discordant, with PET/MR staging being correct in all seven cases. PET/MR significantly outperformed PET/CT overall for accurate staging (P = 0.02). PET/MR outperformed PET/CT in CRC staging. PET/MR might allow accurate local and distant staging of CRC patients during both at the time of diagnosis and during follow-up.

  14. A Clinical and Experimental Comparison of Time of Flight PET/MRI and PET/CT Systems

    OpenAIRE

    Oprea-Lager, Daniela E.; Yaqub, Maqsood; Pieters, Indra C; Reinhard, Rinze; van Moorselaar, Reindert J. A.; van den Eertwegh, Alfons J. M.; Hoekstra, Otto S; Lammertsma, Adriaan A; Boellaard, Ronald

    2015-01-01

    Purpose The purpose of the study was to compare image quality and quantitative accuracy of positron emission tomography/magnetic resonance imaging (PET/MRI) and PET/computed tomography (PET/CT) systems with time of flight PET gantries, using phantom and clinical studies. Procedures Identical phantom experiments were performed on both systems. Calibration, uniformity, and standardized uptake value (SUV) recovery were measured. A clinical PET/CT versus PET/MRI comparison was performed using [18...

  15. Pet allergy: how important for Turkey where there is a low pet ownership rate.

    Science.gov (United States)

    Mungan, Dilşad; Celik, Gülfem; Bavbek, Sevim; Misirligil, Zeynep

    2003-01-01

    Exposure and sensitization to allergens derived from cats/dogs have been shown to represent an important risk factor for allergic respiratory diseases. So far, there has not been any study exploring cat/dog sensitization and related factors in our geographic location. The aim of this study was to determine the sensitization to cats/dogs in a group of patients with rhinitis and/or asthma and to evaluate the relationship between current and childhood exposure and sensitivity to pets. Three hundred twelve consecutive subjects with asthma and/or rhinitis were included in the study and were asked to reply a questionnaire concerning past and current pet ownership and presence of pet-related respiratory symptoms. After performing skin-prick tests, subjects were allocated into three groups: group 1 (n = 103), subjects with nonatopic asthma; group 2 (n = 54), allergic rhinitis and/or asthma patients with pet allergy; group 3 (n = 155), allergic rhinitis and/or asthma patients without pet allergy. Pet hypersensitivity was detected in 54 of 209 atopic subjects (25.8%). There was no difference in the rates of past pet ownership among subjects with (29.6%) and without (23.8%) pet allergy. However, the ratio of current pet ownership was higher in atopic patients with pet allergy (16.6%) than in nonatopic subjects (2.9%; p = 0.02). The prevalence of sensitization to pets in current owners (42.8%) was higher than prevalence of sensitization in patients who never had a pet (22.6%; p = 0.002; odds ratio, 2.67) and who owned a pet at childhood (28.2%; p = 0.038; odds ratio, 1.9). Thirteen subjects (13/54; 24%) described respiratory symptoms when exposed to cats and/or dogs. Rate of past pet ownership was similar in symptomatic and asymptomatic subjects with pet allergy (30.7% versus 29.2%; p > 0.05). Rate of current per ownership was higher in symptomatic subjects than in asymptomatic subjects with pet sensitivity (38.4% versus 9.5%; p pet allergens have the potential to become an

  16. FDG PET and PET/CT: EANM procedure guidelines for tumour PET imaging: version 1.0

    NARCIS (Netherlands)

    Boellaard, R.; O'Doherty, M.J.; Weber, W.A.; Mottaghy, F.M.; Lonsdale, M.N.; Stroobants, S.G.; Oyen, W.J.G.; Kotzerke, J.; Hoekstra, O.S.; Pruim, J.; Marsden, P.K.; Tatsch, K.; Hoekstra, C.J.; Visser, E.P.; Arends, B.; Verzijlbergen, F.J.; Zijlstra, J.M.; Comans, E.F.I.; Lammertsma, A.A.; Paans, A.M.; Willemsen, A.T.; Beyer, T.; Bockisch, A.; Schaefer-Prokop, C.; Delbeke, D.; Baum, R.P.; Chiti, A.; Krause, B.J.

    2010-01-01

    The aim of this guideline is to provide a minimum standard for the acquisition and interpretation of PET and PET/CT scans with [18F]-fluorodeoxyglucose (FDG). This guideline will therefore address general information about [18F]-fluorodeoxyglucose (FDG) positron emission tomography-computed

  17. A proposal of an open PET geometry

    Energy Technology Data Exchange (ETDEWEB)

    Yamaya, Taiga [Molecular Imaging Center, National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage-ku, Chiba, 263-8555 (Japan); Inaniwa, Taku [Research Center for Charged Particle Therapy, National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage-ku, Chiba 263-8555 (Japan); Minohara, Shinichi [Research Center for Charged Particle Therapy, National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage-ku, Chiba 263-8555 (Japan); Yoshida, Eiji [Molecular Imaging Center, National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage-ku, Chiba, 263-8555 (Japan); Inadama, Naoko [Molecular Imaging Center, National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage-ku, Chiba, 263-8555 (Japan); Nishikido, Fumihiko [Molecular Imaging Center, National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage-ku, Chiba, 263-8555 (Japan); Shibuya, Kengo [Molecular Imaging Center, National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage-ku, Chiba, 263-8555 (Japan); Lam, Chih Fung [Molecular Imaging Center, National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage-ku, Chiba, 263-8555 (Japan); Murayama, Hideo [Molecular Imaging Center, National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage-ku, Chiba, 263-8555 (Japan)

    2008-02-07

    The long patient port of a PET scanner tends to put stress on patients, especially patients with claustrophobia. It also prevents doctors and technicians from taking care of patients during scanning. In this paper, we proposed an 'open PET' geometry, which consists of two axially separated detector rings. A long and continuous field-of-view (FOV) including a 360 deg. opened gap between two detector rings can be imaged enabling a fully 3D image reconstruction of all the possible lines-of-response. The open PET will become practical if iterative image reconstruction methods are applied even though image reconstruction of the open PET is analytically an incomplete problem. First we implemented a 'masked' 3D ordered subset expectation maximization (OS-EM) in which the system matrix was obtained from a long 'gapless' scanner by applying a mask to detectors corresponding to the open space. Next, in order to evaluate imaging performance of the proposed open PET geometry, we simulated a dual HR+ scanner (ring diameter of D = 827 mm, axial length of W = 154 mm x 2) separated by a variable gap. The gap W was the maximum limit to have axially continuous FOV of 3W though the maximum diameter of FOV at the central slice was limited to D/2. Artifacts, observed on both sides of the open space when the gap exceeded W, were effectively reduced by inserting detectors partially into unnecessary open spaces. We also tested the open PET geometry using experimental data obtained by the jPET-D4. The jPET-D4 is a prototype brain scanner, which has 5 rings of 24 detector blocks. We simulated the open jPET-D4 with a gap of 66 mm by eliminating 1 block-ring from experimental data. Although some artifacts were seen at both ends of the opened gap, very similar images were obtained with and without the gap. The proposed open PET geometry is expected to lead to realization of in-beam PET, which is a method for an in situ monitoring of charged particle therapy, by

  18. Resistencia mecánica, tasa respiratoria y producción de etileno de caqui 'Fuyu' durante el almacenamiento Mechanical resistance, respiratory rate and the ethylene production of persimmon fruit 'Fuyu' during storage

    Directory of Open Access Journals (Sweden)

    Saul Dussán-Sarria

    2008-10-01

    Full Text Available El caqui 'Fuyu' presenta escasa revisión de literatura en lo que respecta a propiedades mecánicas y comportamiento fisiológico. En este trabajo fue evaluada la alteración de la resistencia mecánica a la compresión del caqui 'Fuyu', el comportamiento respiratorio y la evolución de la producción de etileno durante el almacenamiento. Las frutas fueron cosechadas con dos índices de cosecha: Índice 1, frutas cosechadas 15 a 20 días antes de la madurez comercial y, Índice 2, frutas cosechadas con madurez comercial. Las frutas fueron seleccionadas, empacadas en empaque comercial (caja de cartón y almacenadas bajo dos condiciones de conservación: 1. Con refrigeración (0 ± 1 ºC y 65 ± 1% de HR; 2. Sin refrigeración (22 ± 3 ºC y 71 ± 6% de HR. El módulo de elasticidad del caqui disminuye durante el periodo postcosecha independiente de las condiciones de conservación. El módulo de elasticidad varió entre 3.695,3 y 968,2 kPa. El grado de madurez del caqui 'Fuyu' en el momento de la cosecha, influencia los valores del módulo de elasticidad durante el almacenamiento. El caqui 'Fuyu' presenta comportamiento respiratorio característico de fruto climatérico y el pico de evolución de etileno coincide con el pico climatérico.The Fuyu persimmon fruit presents little literature review of mechanical properties and physiological behavior. In this paper the alteration of mechanical resistance to compression of persimmon fruit 'Fuyu' the respiratory behavior and the evolution of ethylene production during storage were evaluated. The fruits were harvested with two harvest indexes: Index 1, fruits with 15 to 20 days before the commercial index, and Index 2, known as the commercial index. The fruits were selected, packed (commercial carton boxes and stored in two conservation conditions, with refrigeration (0 ± 1 ºC and 65 ± 1% RH and without refrigeration (22 ± 3 ºC and 71 ± 6% RH. The Young's modulus of persimmon fruit decreases

  19. ARMAZENAMENTO E MATURAÇÃO DE BANANAS DO CULTIVAR PRATA (Musa sp EM SACOS DE POLIETILENO CONTENDO ABSORVENTE DE ETILENO STORAGE AND MATURATION OF BANANA (Musa sp. “PRATA” CULTIVAR IN POLYETHYLENE BAGS CONTAINING ETHYLENE ABSORBENT

    Directory of Open Access Journals (Sweden)

    Lincoln F. Zica

    2007-09-01

    Full Text Available

    Este trabalho teve como objetivo estudar um meio adequado de conservação de banana “Prata” (Musa sp., para as condições de mercado interno, utilizando polietileno como modificador do meio envolvente e como embalagem permanente do produtor ao consumidor. Para isto, utilizaram-se os seguintes tratamentos: Testemunha, sem embalagem; Plástico perfurado; Plástico perfurado, contendo absorvente; Plástico sem perfuração; Plástico sem perfuração, contendo absorvente. As bananas tratadas, foram acondicionadas em câmara com temperatura constante de 22 ± 1°C e umidade relativa de 90 ± 3%. Uma vez por dia era feita a leitura da cor da casca e a ventilação de câmara. Com auxílio das análises estatísticas dos dados obtidos concluiu-se que: a. Uso de absorvente de etileno dentro da embalagem plástica, sem perfuração, atrasa o início do amadurecimento, mas não impede que os frutos se tornem imprestáveis para o consumo. b. A melhor embalagem encontrada para ser usada do produtor ao consumidor foi a de plástico perfurado sem absorvente de etileno, que dá um ganho de aproximadamente cinco dias de conservação à temperatura de 22° C.

    This experiment had as its objective the study of an adequate way to conserve the banana “Prata” (Musa sp. in order to meet conditions of the national market. Poliethylene packaging from the producer to the consumer. For this, the following treatments were used: no packaging, perforated plastic, imperforated plastic containing an absorvent, imperforated plastic, imperforated plastic containing an absorvent. The treated banana were stored in a container with a constant temperature of 22 ± 1°C and a relative humidity of 90 ± 3%. Once a day a reading was taken of the skin color and the room was ventilated. With the help of statistical analysis of the obtained

  20. Indeterminate findings on oncologic PET/CT: What difference dose PET/MRI make?

    Energy Technology Data Exchange (ETDEWEB)

    Fraum, Tyler J.; Fowler, Kathryn J.; McConathy, Jonathan; Dehdashti, Farokh [Mallinckrodt Institute of Radiology, Washington University School of Medicine, Saint Louis (United States)

    2016-12-15

    Positron emission tomography/computed tomography (PET/CT) with 2-deoxy-2-[{sup 18}F]fluoro-D-glucose (FDG) has become the standard of care for the initial staging and subsequent treatment response assessment of many different malignancies. Despite this success, PET/CT is often supplemented by MRI to improve assessment of local tumor invasion and to facilitate detection of lesions in organs with high background FDG uptake. Consequently, PET/MRI has the potential to expand the clinical value of PET examinations by increasing reader certainty and reducing the need for subsequent imaging. This study evaluates the ability of FDG-PET/MRI to clarify findings initially deemed indeterminate on clinical FDG-PET/CT studies. A total of 190 oncology patients underwent whole-body PET/CT, immediately followed by PET/MRI utilizing the same FDG administration. Each PET/CT was interpreted by our institution's nuclear medicine service as a standard-of-care clinical examination. Review of these PET/CT reports identified 31 patients (16 %) with indeterminate findings. Two readers evaluated all 31 PET/CT studies, followed by the corresponding PET/MRI studies. A consensus was reached for each case, and changes in interpretation directly resulting from PET/MRI review were recorded. Interpretations were then correlated with follow-up imaging, pathology results, and other diagnostic studies. In 18 of 31 cases with indeterminate findings on PET/CT, PET/MRI resulted in a more definitive interpretation by facilitating the differentiation of infection/inflammation from malignancy (15/18), the accurate localization of FDG-avid lesions (2/18), and the characterization of incidental non-FDG-avid solid organ lesions (1/18). Explanations for improved reader certainty with PET/MRI included the superior soft tissue contrast of MRI and the ability to assess cellular density with diffusion-weighted imaging. The majority (12/18) of such cases had an appropriate standard of reference; in all 12 cases

  1. Preparation and Characterization of Flame Retardant PET Fiber with Microencapsulated CMSs/PET

    Directory of Open Access Journals (Sweden)

    NIU Mei

    2016-06-01

    Full Text Available The core-shell carbon microspheres(CMSs/polyethylene terephthalate(PET capsule (PCMSs by in situ polymerization was selected as flame retardant. The flame-retardant PCMSs/PET functional fiber was prepared by melt spinning method. The structure and properties of PET fiber with different mass fractions of flame retardant were characterized by SEM, sound velocimeter, tensile tester and limit oxygen index apparatus. The results show that PCMSs has a good compatibility and dispersion within PET matrix, and the excellent moisture absorption and flame retardant properties of functional PET fiber with smooth surface is obtained when the mass fraction of PCMSs is 0.6%, but the mechanical property of PCMSs/PET fiber with 0.6% PCMSs is a little lower than the PCMSs/PET fiber with 0.2% PCMSs.

  2. [Pet ownership and health status of pets from immunocompromised children, with emphasis in zoonotic diseases].

    Science.gov (United States)

    Abarca V, Katia; López Del P, Javier; Peña D, Anamaría; López G, J Carlos

    2011-06-01

    To characterize pet ownership and pet health status in families of immunocompromised (IS) children, with emphasis in zoonotic diseases. Families of IS children from two hospitals in Santiago, Chile, were interviewed and their pets were evaluated by veterinary examination, coproparasitologic and skin dermatophytes test. In specific cases, other laboratory tests were performed in IS children or their relatives. 47 out of 70 contacted families had pets, 42 participated in the study. Several risk factors for IS children were observed, as having a turtle as a pet and to clean cat or turtle faeces. Lack of adequate veterinary control, immunizations and deparasitation of pets were observed. Some animals showed zoonotic diseases or agents, as Brucella canis, Cryptosporidium sp, Giardia intestinalis, Toxocara canis and scabies. 44% of dogs had ticks and 37% had fleas, both potential vectors of infections. Our results suggest that policies to provide safer pet contact in IS children are needed.

  3. Human health implications of Salmonella-contaminated natural pet treats and raw pet food.

    Science.gov (United States)

    Finley, Rita; Reid-Smith, Richard; Weese, J Scott

    2006-03-01

    Human salmonellosis occurs mainly as a result of handling or consuming contaminated food products, with a small percentage of cases being related to other, less well-defined exposures, such as contact with companion animals and natural pet treats. The increasing popularity of raw food diets for companion animals is another potential pet-associated source of Salmonella organisms; however, no confirmed cases of human salmonellosis have been associated with these diets. Pets that consume contaminated pet treats and raw food diets can be colonized with Salmonella organisms without exhibiting clinical signs, making them a possible hidden source of contamination in the household. Pet owners can reduce their risk of acquiring Salmonella organisms by not feeding natural pet treats and raw food diets to their pets, whereas individuals who investigate cases of salmonellosis or interpret surveillance data should be aware of these possible sources of Salmonella organisms.

  4. Proposal of a synthetic ethylene-vinyl acetate bench model for surgical foundations learning: suture training Modelo de bancada sintético de etileno vinil acetato para a aprendizagem das bases da cirurgia: treinamento de suturas

    Directory of Open Access Journals (Sweden)

    Érika Malheiros Bastos

    2011-04-01

    Full Text Available Due to ethical and legal aspects involved in the handling of cadavers and animals the synthetic simulators are an alternative for learning how to suture technique plus the practice of various procedures such as incision and surgical flap. In this context, this paper describes and propose the use of a synthetic model manufactured from plates of ethylene-vinyl acetate (EVA to teach primary surgical skills in medical students with no previous exposure to surgery. The model that provides the convenience of being easily reproducible, allowing the students in training can thus improve their skills before applying the technique in clinical practice.Devido aos aspectos éticos e legais envolvidos no manuseio de cadáveres e animais, os simuladores sintéticos surgem como alternativa para o ensino-aprendizagem de técnicas de sutura e simulação de procedimentos, como a confecção de incisões e retalhos cirúrgicos. Neste âmbito é proposto e descrito um modelo de bancada sintético confeccionado a partir de etileno vinil acetato (EVA para o ensino de habilidades cirúrgicas básicas, em estudantes de medicina sem exposição prévia a cirurgia. O modelo fornece a praticidade de ser reprodutível, barato e de fácil aquisição, possibilitando que o acadêmico em formação possa, portanto, aperfeiçoar suas habilidades antes de aplicar a técnica na prática clínica.

  5. Influência do tratamento químico da fibra de bananeira em compósitos de poli(etileno-co-acetato de vinila com e sem agente de expansão

    Directory of Open Access Journals (Sweden)

    Matheus V. G. Zimmermann

    2014-01-01

    Full Text Available Neste trabalho foi avaliada a influência do tratamento alcalino na fibra de bananeira (FB e seu uso como agente de reforço em compósitos expandidos de poli(etileno-co-acetato de vinila - EVA. O processo de mistura dos compósitos ocorreu em um misturador de rolos aberto e após conformados e expandidos em uma prensa aquecida com moldes de volumes variáveis. Os compósitos foram avaliados por suas propriedades mecânicas, térmicas e morfológicas. Os resultados indicam que o tratamento alcalino promove a extração de componentes menos estáveis na FB, tais como a lignina, hemicelulose, ceras e óleos de baixo peso molecular. O uso da FB nos compósitos proporciona um decréscimo das propriedades mecânicas de resistência à tração e rasgo em relação ao EVA puro devido a moderadas propriedades de interface polímero-fibra. Nos compósitos expandidos, as propriedades mecânicas decrescem com a diminuição da densidade em função da maior presença de espaços vazios no interior dos compósitos, porém as propriedades mecânicas específicas de resistência ao rasgo apresentaram melhores resultados com 10 pcr de FB em todos os moldes utilizados.

  6. Evaluation of attenuation correction in cardiac PET using PET/MR.

    Science.gov (United States)

    Lau, Jeffrey M C; Laforest, R; Sotoudeh, H; Nie, X; Sharma, S; McConathy, J; Novak, E; Priatna, A; Gropler, R J; Woodard, P K

    2017-06-01

    Simultaneous acquisition Positron emission tomography/magnetic resonance (PET/MR) is a new technology that has potential as a tool both in research and clinical diagnosis. However, cardiac PET acquisition has not yet been validated using MR imaging for attenuation correction (AC). The goal of this study is to evaluate the feasibility of PET imaging using a standard 2-point Dixon volume interpolated breathhold examination (VIBE) MR sequence for AC. Evaluation was performed in both phantom and patient data. A chest phantom containing heart, lungs, and a lesion insert was scanned by both PET/MR and PET/CT. In addition, 30 patients underwent whole-body 18F-fluorodeoxyglucose PET/CT followed by simultaneous cardiac PET/MR. Phantom study showed 3% reduction of activity values in the myocardium due to the non-inclusion of the phased array coil in the AC. In patient scans, average standardized uptake values (SUVs) obtained by PET/CT and PET/MR showed no significant difference (n = 30, 4.6 ± 3.5 vs 4.7 ± 2.8, P = 0.47). There was excellent per patient correlation between the values acquired by PET/CT and PET/MR (R 2 = 0.97). Myocardial SUVs PET imaging using MR for AC shows excellent correlation with myocardial SUVs obtained by standard PET/CT imaging. The 2-point Dixon VIBE MR technique can be used for AC in simultaneous PET/MR data acquisition.

  7. Simultaneous PET/MR imaging with a radio frequency-penetrable PET insert.

    Science.gov (United States)

    Grant, Alexander M; Lee, Brian J; Chang, Chen-Ming; Levin, Craig S

    2017-01-01

    A brain sized radio frequency (RF)-penetrable PET insert has been designed for simultaneous operation with MRI systems. This system takes advantage of electro-optical coupling and battery power to electrically float the PET insert relative to the MRI ground, permitting RF signals to be transmitted through small gaps between the modules that form the PET ring. This design facilitates the use of the built-in body coil for RF transmission and thus could be inserted into any existing MR site wishing to achieve simultaneous PET/MR imaging. The PET detectors employ nonmagnetic silicon photomultipliers in conjunction with a compressed sensing signal multiplexing scheme, and optical fibers to transmit analog PET detector signals out of the MRI room for decoding, processing, and image reconstruction. The PET insert was first constructed and tested in a laboratory benchtop setting, where tomographic images of a custom resolution phantom were successfully acquired. The PET insert was then placed within a 3T body MRI system, and tomographic resolution/contrast phantom images were acquired both with only the B0 field present, and under continuous pulsing from different MR imaging sequences. The resulting PET images have comparable contrast-to-noise ratios (CNR) under all MR pulsing conditions: The maximum percent CNR relative difference for each rod type among all four PET images acquired in the MRI system has a mean of 14.0 ± 7.7%. MR images were successfully acquired through the RF-penetrable PET shielding using only the built-in MR body coil, suggesting that simultaneous imaging is possible without significant mutual interference. These results show promise for this technology as an alternative to costly integrated PET/MR scanners; a PET insert that is compatible with any existing clinical MRI system could greatly increase the availability, accessibility, and dissemination of PET/MR. © 2016 American Association of Physicists in Medicine.

  8. Development of PET insert for simultaneous PET/MR imaging of human brain

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Jiwoong; Choi, Yong; Jung, Jin Ho; Kim, Sangsu; Im, Ki Chun; Lim, Hyun Keong [Molecular Imaging Research & Education (MiRe) Laboratory, Department of Electronic Engineering, Sogang University, Seoul (Korea, Republic of); Oh, Changheun; Park, HyunWook; Cho, Gyuseong [Departments of Electrical Engineering and Nuclear and Quantum Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon (Korea, Republic of)

    2014-07-29

    Recently, there has been great interest on the development of combined PET/MR, which is a useful tool for both functional and anatomic imaging. The purpose of this study was to develop a MR compatible PET insert for simultaneous PET and MR imaging of human brain and to evaluate the performance of the hybrid PET-MRI. The PET insert consisted of 18 detector blocks arranged in a ring of 390 mm diameter with 60 mm axial FOV. Each detector block was composed of 4 × 4 matrix of detector modules, each of which consisted of a 4 × 4 array LYSO coupled to a 4 × 4 GAPD array. The PET gantry was shielded with gold-plated conductive fabric tapes. The charge signals of PET detector transferred via 4 m long flat cables were fed into the position decoder circuits (PDCs) and then transferred to FPGA-embedded DAQ modules. The PDCs and DAQ modules were enclosed in an aluminum box and located at the rear of the MR bore inside MRI room. 3-T human MRIs of two different vendors were used to evaluate the MR compatibility of developed PET insert. No significant changes of the PET performance and the homogeneity of MR images caused by the non-compatibility of PET-MRI were observed with the 2 different MRIs. The signal intensities of MR images were slightly degraded (<3.6%) with the both MRI systems. The difference between independently and simultaneously acquired PET images of brain phantom was negligibly small (<4.3%). High quality simultaneous brain PET and MRI of 3 normal volunteers were successfully acquired. Experimental results indicate that the high performance compact and lightweight PET insert for hybrid PET/MRI, which could be utilized with the MRI from various manufactures, can be developed using GAPD arrays and charge signal transmission method proposed in this study.

  9. Clinical PET/MR Imaging in Oncology

    DEFF Research Database (Denmark)

    Kjær, Andreas; Torigian, Drew A.

    2016-01-01

    . The question, therefore, arises regarding what the future clinical applications of PET/MR imaging will be. In this article, the authors discuss ways in which PET/MR imaging may be used in future applications that justify the added cost, predominantly focusing on oncologic applications. The authors suggest...

  10. Towards enhanced PET quantification in clinical oncology

    DEFF Research Database (Denmark)

    Zaidi, Habib; Karakatsanis, Nicolas

    2018-01-01

    and software system specifications, tracer kinetics, motion, scan protocol design and limitations in current image-derived PET metrics. Given the relatively large number of PET metrics reported in the literature, the selection of the best metric for fulfilling a specific task in a particular application...

  11. Evaluating College Student Interest in Pet Therapy

    Science.gov (United States)

    Adamle, Kathleen N.; Riley, Tracy A.; Carlson, Tracey

    2009-01-01

    The first year of college can be extremely stressful, especially for students residing on campus. Objective: The authors obtained information from college freshmen about their relationships with pets and investigated interest in a pet therapy program as social support for transient stressful periods. Participants: As part of a university…

  12. Integrating Pet Therapy into Daily School Life

    Science.gov (United States)

    Brous, Miriam T.

    2010-01-01

    Stories abound in literature of the ways that people and their pets have fostered and created valuable relationships. More recently, research has shown a strong impact from the pet relationship in health-related settings. Positive changes have been seen in people developing resilience, self-reliance, and in making progress in treatment. Children…

  13. Other PET tracers for neuroendocrine tumors

    NARCIS (Netherlands)

    Koopmans, Klaas Pieter; Glaudemans, Andor W J M

    In this article the applicability of (124)I-MIBG and (11)C-5-HTP PET for the detection of abdominal gastro-enteropancreatic neuroendocrine tumors is discussed. (124)I-MIBG is a positron-emitting variant of (123)I-MIBG and therefore suited for PET imaging. Due to the better intrinsic characteristics

  14. PET-container collection systems in Europe

    NARCIS (Netherlands)

    Logtenberg, T.; Groot, J.L.B. de; Rink, T.

    1996-01-01

    This report presents the results of a TNO study of the present situation in Europe with regard to PET-bottle recycling. The overview concentrates on the main PET-bottles consuming countries in Europe i.e.: France, Italy, Spain and the UK. In addition the system in Belgium is presented. Applying a

  15. Developing simplified Regional Potential Evapotranspiration (PET ...

    African Journals Online (AJOL)

    Regional Potential Evapotranspiration (PET) estimation method was developed to estimate the potential evapotranspiration (reference evapotranspiration) over Abbay Basin as a function of basin maximum and minimum temperature, and modulated by site specific elevation data. The method is intended to estimate PET in ...

  16. Pet Ownership and Health Status during Bereavement.

    Science.gov (United States)

    Akiyama, Hiroko; And Others

    1987-01-01

    Investigated impact of pet ownership on the health status of recently widowed urban middle-class women. Findings suggest pet ownership may have a salutary effect on the adjustment of recently widowed women in terms of symptom experiences and proneness to utilization of medication. (Author/KS)

  17. Quantitative Techniques in PET-CT Imaging

    NARCIS (Netherlands)

    Basu, Sandip; Zaidi, Habib; Holm, Soren; Alavi, Abass

    The appearance of hybrid PET/CT scanners has made quantitative whole body scanning of radioactive tracers feasible. This paper deals with the novel concepts for assessing global organ function and disease activity based on combined functional (PET) and structural (CT or MR) imaging techniques, their

  18. PET/MRI – Technical Review

    Science.gov (United States)

    Muzic, Raymond F.; DiFilippo, Frank P.

    2015-01-01

    PET/MR is a hybrid imaging technology with the potential to combine the molecular and functional information of PET with the soft-tissue contrast of MR. Herein we review the technical features and challenges of putting these different technologies together. We emphasize the conceptual to make the material accessible to a wide audience. We begin by reviewing PET/CT, a more mature multi-modality imaging technology, to provide a basis for comparison to the history of PET/MR development. We discuss the motivation and challenges of PET/MR and different approaches that have been used to meet the challenges. We conclude with a speculation about the future of this exciting imaging method. PMID:25497909

  19. Obtaining a pet: realistic expectations.

    Science.gov (United States)

    Marder, Amy; Duxbury, Margaret M

    2008-09-01

    Millions of dog-human relationships fail each year-some from simple and preventable mismatches. False or unrealistic expectations of a dog's behavior are a common reason for failed human-animal bonds. Veterinarians can reduce the incidence of false expectations and thereby increase the likelihood of successful adoptions by offering preadoption counseling to help clients sort through the many factors involved in the process of successful pet selection, by preparing clients to take on the important tasks of puppy socialization and the management of the home learning environment, and by educating new owners about the needs and behavior of dogs.

  20. Exotic pet medicine I. Snakes.

    Science.gov (United States)

    Jacobson, E R

    1993-11-01

    Of the 6,000 extant species of reptiles, approximately 2500 are snakes. Several dozen species of snakes have become popular in the pet trade, and to meet the increased demand, more and more species are being bred in captivity. Along with this popularity comes the need for more sound veterinary expertise. Although much biomedical information on snakes exists in the literature and can be found in texts on reptile medicine, few reviews have tried to consolidate the literature on this subject. The purpose of this article is to bring together information on the most pertinent aspects of snake medicine and disease.

  1. Common Emergencies in Pet Birds.

    Science.gov (United States)

    Stout, Jane D

    2016-05-01

    Treating avian emergencies can be a challenging task. Pet birds often mask signs of illness until they are critically ill and require quick initiation of supportive care with minimal handling to stabilize them. This article introduces the clinician to common avian emergency presentations and details initial therapeutics and diagnostics that can be readily performed in the small-animal emergency room. Common disease presentations covered include respiratory and extrarespiratory causes of dyspnea, gastrointestinal signs, reproductive disease, neurologic disorders, trauma, and toxin exposure. The duration and severity of the avian patient's disease and the clinician's initiation of appropriate therapy often determines clinical outcome. Copyright © 2016 Elsevier Inc. All rights reserved.

  2. SPECT og PET i neurobiologien

    DEFF Research Database (Denmark)

    Paulson, O B; Lassen, N A

    1997-01-01

    PET (positron emission tomography) and SPECT (single photon emission computed tomography) are isotopic methods in which the distribution is registered of radiolabelled tracers given in such small amounts that they are without effect on the organism or the organism's disposal of them. Thus, a series...... of important biological processes in the intact organism can be studied. The methods have been used in many disciplines but in particular for neurobiological research on the brain--e.g., the brain's regional blood circulation and mapping of the brain's functional structure. The methods have also been used...

  3. Qualidade da maçã "Gala" armazenada em atmosfera controlada associada à absorção e ao controle da síntese e da ação do etileno Quality of 'Gala' apples stored in controlled atmosphere associated with ethylene absorption and control of its syntheses and action

    Directory of Open Access Journals (Sweden)

    Auri Brackmann

    2008-11-01

    Full Text Available Este trabalho teve por objetivo avaliar o efeito da inibição da biossíntese de etileno no período pré-colheita e o efeito da inibição da ação ou da absorção do etileno durante o armazenamento em atmosfera controlada (AC; 1,2kPa de O2 + 2,5kPa de CO2 a 0°C sobre a qualidade de maçãs cv. "Gala". Além disso, avaliou-se também o efeito combinado desses tratamentos. Os tratamentos avaliados foram: (1 armazenamento em AC (controle; (2 aplicação pré-colheita de AVG; (3 AVG + aplicação pós-colheita de 1-MCP; (4 aplicação de 1-MCP; (5 AVG + absorção do etileno durante todo o período de armazenamento; e (6 absorção de etileno. Após oito meses de armazenamento mais sete dias a 20°C, os frutos tratados com AVG apresentaram menor atividade da ACC oxidase. A combinação de AVG + 1-MCP ou AVG + absorção de etileno mantiveram menor produção de etileno até cinco dias de vida de prateleira a 20°C. Além disso, a firmeza da polpa dos frutos submetidos a esses tratamentos combinados manteve-se mais elevada. A cor de fundo da epiderme manteve-se mais verde nos frutos tratados com AVG, independente do tratamento em pós-colheita, demonstrando que a modificação da coloração da epiderme é mais afetada pelo etileno produzido ainda na pré-colheita. Portanto, conclui-se que a aplicação em pré-colheita de AVG associada com a absorção do etileno durante o armazenamento é mais eficiente no controle da maturação de maçãs "Gala", no entanto, a aplicação pré-colheita de AVG combinada com a aplicação pós-colheita de 1-MCP também é eficiente.This research aimed to evaluate the effect of inhibition the ethylene biosynthesis at the pre-harvest stage, the ethylene action and the absorption from the controlled atmosphere storage room on the quality of 'Gala' apples. The experimental design was entirely randomized, with four replicates and the experimental unit composed by 25 fruits. The treatments were: (1 CA storage only

  4. Híbridos de poli(oxido de etileno-b-amida-6 e ZrO2 sol-gel: preparação, caracterização e aplicação em processos de separação por membranas

    Directory of Open Access Journals (Sweden)

    Zoppi Rita A.

    2000-01-01

    Full Text Available Híbridos constituídos de poli(óxido de etileno-b-amida-6, PEBAX, e óxido de zircônio foram preparados a partir da hidrólise e condensação do tetraisopropóxido de zircônio em solução contendo o polímero orgânico dissolvido. Estes foram caracterizados por termogravimetria, calorimetria diferencial de varredura, espectroscopia na região do infravermelho e microscopia eletrônica. Os resultados obtidos mostraram que a incorporação da fase inorgânica parece promover a degradação do polímero orgânico. Membranas compostas constituídas de um suporte poroso de poli(fluoreto de vinilideno, PVDF, e uma camada filtrante de PEBAX/ZrO2 foram preparadas e caracterizadas por microscopia eletrônica. Foram realizados ensaios de permeação de água e de soluções aquosas contendo poli(etileno glicol de diferentes massas molares. Para determinar a rejeição de fosfato, foram realizados ensaios de permeação de uma solução aquosa de KH2PO4. Independente da composição da camada filtrante, foram obtidos valores de rejeição de fosfato da ordem de 80%.

  5. Preoperative staging of non-small cell lung cancer: prospective comparison of PET/MR and PET/CT.

    Science.gov (United States)

    Lee, Sang Min; Goo, Jin Mo; Park, Chang Min; Yoon, Soon Ho; Paeng, Jin Chul; Cheon, Gi Jeong; Kim, Young Tae; Park, Young Sik

    2016-11-01

    To prospectively compare the accuracies of PET/MR and PET/CT in the preoperative staging of non-small cell lung cancer (NSCLC). Institutional review board approval and patients' informed consents were obtained. 45 patients with proven or radiologically suspected lung cancer which appeared to be resectable on CT were enrolled. PET/MR was performed for the preoperative staging of NSCLC followed by PET/CT without contrast enhancement on the same day. Dedicated MR images including diffusion weighted images were obtained. Readers assessed PET/MR and PET/CT with contrast-enhanced CT. Accuracies of PET/MR and PET/CT for NSCLC staging were compared. Primary tumour stages (n = 40) were correctly diagnosed in 32 patients (80.0 %) on PET/MR and in 32 patients (80.0 %) on PET/CT (P = 1.0). Node stages (n = 42) were correctly determined in 24 patients (57.1 %) on PET/MR and in 22 patients (52.4 %) on PET/CT (P = 0.683). Metastatic lesions in the brain, bone, liver, and pleura were detected in 6 patients (13.3 %). PET/MR missed one patient with pleural metastasis while PET/CT missed one patient with solitary brain metastasis and two patients with pleural metastases (P = 0.480). This study demonstrated that PET/MR in combination with contrast-enhanced CT was comparable to PET/CT in the preoperative staging of NSCLC while reducing radiation exposure. • PET/MR can be comparable to PET/CT for preoperative NSCLC staging. • PET/MR and PET/CT show excellent correlation in measuring SUVmax of primary lesions. • Using PET/MR, estimated radiation dose can decrease by 31.1 % compared with PET/CT.

  6. Comportamento pós-colheita de caquis cv. Fuyu, através da atmosfera modificada passiva e da adsorção de etileno, armazenados sob refrigeração Postharvest behavior of persimmons cv. Fuyu through passive modified atmosphere and ethylene adsorption stored under refrigeration

    Directory of Open Access Journals (Sweden)

    Leandro Camargo Neves

    2006-12-01

    Full Text Available O trabalho foi realizado no Departamento de Ciência e Tecnologia Agroindustrial, da UFPel/Pelotas, com o objetivo de avaliar a utilização de embalagens de polietileno de baixa densidade (PEBD e do adsorvedor de etileno em caquis cv. Fuyu. Na safra de 2000-2001, os frutos foram armazenados a granel, em embalagens de PEBD de 0,022 mm contendo doze e 40 frutos e em embalagens de PEBD de 0,033 mm contendo doze frutos, sendo que apenas metade das embalagens possuía o sachê adsorvedor de etileno. De acordo com as variáveis analisadas (distúrbios fisiológicos, concentração/produção de CO2 e etileno, os frutos acondicionados nas embalagens de 0,022 mm contendo doze frutos, com e sem o adsorvedor, apresentavam-se em estádio menos avançado de amadurecimento e com qualidade superior aos demais tratamentos. Já na safra de 2001 - 2002, sob os mesmos parâmetros avaliados no ano anterior, foram testados o armazenamento a granel e o armazenamento em embalagens de PEBD de 0,022 mm, contendo doze, dezoito e 24 frutos, também com e sem a utilização de sachê adsorvedor de etileno. Após 90 dias de armazenamento refrigerado (AR, mais os cinco dias de simulação de comercialização, os frutos acondicionados nas embalagens de 0,022 mm, contendo doze e dezoito frutos, independentemente do sistema de adsorção de etileno, apresentaram os melhores resultados em todas as variáveis testadas.The experiments were carried out at the Science and Technology Agroindustry Department of UFPel/Pelotas, with the objective to improve the use of polyethylene packing of low density (PPLD and the adsorption of ethylene, in Fuyu persimmons. During the season of 00/01, the fruits were stored without packing, in 0,022 mm PPLD packing with capacity for 12 or 40 fruits and in 0,033 mm PPLD packing with capacity for 12 units. Except for the control treatment, all the other treatments were combined with (50% or without (50% ethylene absorption. According to the analyzed

  7. The spatial distribution of pet dogs and pet cats on the island of Ireland

    Science.gov (United States)

    2011-01-01

    Background There is considerable international research regarding the link between human demographics and pet ownership. In several international studies, pet ownership was associated with household demographics including: the presence of children in the household, urban/rural location, level of education and age/family structure. What is lacking across all these studies, however, is an understanding of how these pets are spatially distributed throughout the regions under study. This paper describes the spatial distribution of pet dog and pet cat owning households on the island of Ireland. Results In 2006, there were an estimated 640,620 pet dog owning households and 215,542 pet cat owning households in Ireland. These estimates are derived from logistic regression modelling, based on household composition to determine pet dog ownership and the type of house to determine pet cat ownership. Results are presented using chloropleth maps. There is a higher density of pet dog owning households in the east of Ireland and in the cities than the west of Ireland and rural areas. However, in urban districts there are a lower proportion of households owning pet dogs than in rural districts. There are more households with cats in the urban areas, but the proportion of households with cats is greater in rural areas. Conclusions The difference in spatial distribution of dog ownership is a reflection of a generally higher density of households in the east of Ireland and in major cities. The higher proportion of ownership in the west is understandable given the higher proportion of farmers and rural dwellings in this area. Spatial representation allows us to visualise the impact of human household distribution on the density of both pet dogs and pet cats on the island of Ireland. This information can be used when analysing risk of disease spread, for market research and for instigating veterinary care. PMID:21663606

  8. The spatial distribution of pet dogs and pet cats on the island of Ireland

    Directory of Open Access Journals (Sweden)

    More Simon J

    2011-06-01

    Full Text Available Abstract Background There is considerable international research regarding the link between human demographics and pet ownership. In several international studies, pet ownership was associated with household demographics including: the presence of children in the household, urban/rural location, level of education and age/family structure. What is lacking across all these studies, however, is an understanding of how these pets are spatially distributed throughout the regions under study. This paper describes the spatial distribution of pet dog and pet cat owning households on the island of Ireland. Results In 2006, there were an estimated 640,620 pet dog owning households and 215,542 pet cat owning households in Ireland. These estimates are derived from logistic regression modelling, based on household composition to determine pet dog ownership and the type of house to determine pet cat ownership. Results are presented using chloropleth maps. There is a higher density of pet dog owning households in the east of Ireland and in the cities than the west of Ireland and rural areas. However, in urban districts there are a lower proportion of households owning pet dogs than in rural districts. There are more households with cats in the urban areas, but the proportion of households with cats is greater in rural areas. Conclusions The difference in spatial distribution of dog ownership is a reflection of a generally higher density of households in the east of Ireland and in major cities. The higher proportion of ownership in the west is understandable given the higher proportion of farmers and rural dwellings in this area. Spatial representation allows us to visualise the impact of human household distribution on the density of both pet dogs and pet cats on the island of Ireland. This information can be used when analysing risk of disease spread, for market research and for instigating veterinary care.

  9. The spatial distribution of pet dogs and pet cats on the island of Ireland.

    Science.gov (United States)

    Downes, Martin J; Clegg, Tracy A; Collins, Daniel M; McGrath, Guy; More, Simon J

    2011-06-10

    There is considerable international research regarding the link between human demographics and pet ownership. In several international studies, pet ownership was associated with household demographics including: the presence of children in the household, urban/rural location, level of education and age/family structure. What is lacking across all these studies, however, is an understanding of how these pets are spatially distributed throughout the regions under study. This paper describes the spatial distribution of pet dog and pet cat owning households on the island of Ireland. In 2006, there were an estimated 640,620 pet dog owning households and 215,542 pet cat owning households in Ireland. These estimates are derived from logistic regression modelling, based on household composition to determine pet dog ownership and the type of house to determine pet cat ownership. Results are presented using chloropleth maps. There is a higher density of pet dog owning households in the east of Ireland and in the cities than the west of Ireland and rural areas. However, in urban districts there are a lower proportion of households owning pet dogs than in rural districts. There are more households with cats in the urban areas, but the proportion of households with cats is greater in rural areas. The difference in spatial distribution of dog ownership is a reflection of a generally higher density of households in the east of Ireland and in major cities. The higher proportion of ownership in the west is understandable given the higher proportion of farmers and rural dwellings in this area. Spatial representation allows us to visualise the impact of human household distribution on the density of both pet dogs and pet cats on the island of Ireland. This information can be used when analysing risk of disease spread, for market research and for instigating veterinary care.

  10. 24 CFR 5.318 - Discretionary pet rules.

    Science.gov (United States)

    2010-04-01

    ... Development GENERAL HUD PROGRAM REQUIREMENTS; WAIVERS Pet Ownership for the Elderly or Persons With Disabilities General Requirements § 5.318 Discretionary pet rules. Pet rules promulgated by project owners and... 24 Housing and Urban Development 1 2010-04-01 2010-04-01 false Discretionary pet rules. 5.318...

  11. Myths and misperceptions about ingredients used in commercial pet foods.

    Science.gov (United States)

    Laflamme, Dottie; Izquierdo, Oscar; Eirmann, Laura; Binder, Stephen

    2014-07-01

    Information and misinformation about pet nutrition and pet foods, including ingredients used in pet foods, is widely available through various sources. Often, this "information" raises questions or concerns among pet owners. Many pet owners will turn to their veterinarian for answers to these questions. One of the challenges that veterinarians have is keeping up with the volume of misinformation about pet foods and sorting out fact from fiction. The goal of this article is to provide facts regarding some common myths about ingredients used in commercial pet foods so as to better prepare veterinarians to address their client's questions. Copyright © 2014 Elsevier Inc. All rights reserved.

  12. Benefits and liabilities of pets for the homeless.

    Science.gov (United States)

    Kidd, A H; Kidd, R M

    1994-06-01

    Observations in the streets and parks of San Francisco East Bay cities and suburbs suggested that many of the homeless people own and maintain pet animals in spite of circumstances and environmental conditions. Accordingly, 105 homeless adult men and women, half of whom owned pets, were interviewed for this pilot study. Responses indicated that homeless pet-owners were extremely attached to their pets and had owned significantly more pets during childhood and adolescence than nonowners although there were no significant differences in attachment to pets between parents and nonparents or between married and single persons. Providing food and veterinary care for pets, however, was a very significant problem for the majority of the homeless pet-owners. It was clear that many homeless adults did have pets which were important for their mental and physical health and that pet care was associated with unique problems.

  13. Dose Optimization in TOF-PET/MR Compared to TOF-PET/CT.

    Science.gov (United States)

    Queiroz, Marcelo A; Delso, Gaspar; Wollenweber, Scott; Deller, Timothy; Zeimpekis, Konstantinos; Huellner, Martin; de Galiza Barbosa, Felipe; von Schulthess, Gustav; Veit-Haibach, Patrick

    2015-01-01

    To evaluate the possible activity reduction in FDG-imaging in a Time-of-Flight (TOF) PET/MR, based on cross-evaluation of patient-based NECR (noise equivalent count rate) measurements in PET/CT, cross referencing with phantom-based NECR curves as well as initial evaluation of TOF-PET/MR with reduced activity. A total of 75 consecutive patients were evaluated in this study. PET/CT imaging was performed on a PET/CT (time-of-flight (TOF) Discovery D 690 PET/CT). Initial PET/MR imaging was performed on a newly available simultaneous TOF-PET/MR (Signa PET/MR). An optimal NECR for diagnostic purposes was defined in clinical patients (NECRP) in PET/CT. Subsequent optimal activity concentration at the acquisition time ([A]0) and target NECR (NECRT) were obtained. These data were used to predict the theoretical FDG activity requirement of the new TOF-PET/MR system. Twenty-five initial patients were acquired with (retrospectively reconstructed) different imaging times equivalent for different activities on the simultaneous PET/MR for the evaluation of clinically realistic FDG-activities. The obtained values for NECRP, [A]0 and NECRT were 114.6 (± 14.2) kcps (Kilocounts per second), 4.0 (± 0.7) kBq/mL and 45 kcps, respectively. Evaluating the NECRT together with the phantom curve of the TOF-PET/MR device, the theoretical optimal activity concentration was found to be approximately 1.3 kBq/mL, which represents 35% of the activity concentration required by the TOF-PET/CT. Initial evaluation on patients in the simultaneous TOF-PET/MR shows clinically realistic activities of 1.8 kBq/mL, which represent 44% of the required activity. The new TOF-PET/MR device requires significantly less activity to generate PET-images with good-to-excellent image quality, due to improvements in detector geometry and detector technologies. The theoretically achievable dose reduction accounts for up to 65% but cannot be fully translated into clinical routine based on the coils within the FOV and MR

  14. Quantitative, Simultaneous PET/MRI for Intratumoral Imaging with an MRI-Compatible PET Scanner

    Science.gov (United States)

    Ng, Thomas S.C.; Bading, James R.; Park, Ryan; Sohi, Hargun; Procissi, Daniel; Colcher, David; Conti, Peter S.; Cherry, Simon R.; Raubitschek, Andrew A.; Jacobs, Russell E.

    2012-01-01

    Noninvasive methods are needed to explore the heterogeneous tumor microenvironment and its modulation by therapy. Hybrid PET/MRI systems are being developed for small-animal and clinical use. The advantage of these integrated systems depends on their ability to provide MR images that are spatially coincident with simultaneously acquired PET images, allowing combined functional MRI and PET studies of intratissue heterogeneity. Although much effort has been devoted to developing this new technology, the issue of quantitative and spatial fidelity of PET images from hybrid PET/MRI systems to the tissues imaged has received little attention. Here, we evaluated the ability of a first-generation, small-animal MRI-compatible PET scanner to accurately depict heterogeneous patterns of radiotracer uptake in tumors. Methods Quantitative imaging characteristics of the MRI-compatible PET (PET/MRI) scanner were evaluated with phantoms using calibration coefficients derived from a mouse-sized linearity phantom. PET performance was compared with a commercial small-animal PET system and autoradiography in tumor-bearing mice. Pixel and structure-based similarity metrics were used to evaluate image concordance among modalities. Feasibility of simultaneous PET/MRI functional imaging of tumors was explored by following 64Cu-labeled antibody uptake in relation to diffusion MRI using cooccurrence matrix analysis. Results The PET/MRI scanner showed stable and linear response. Activity concentration recovery values (measured and true activity concentration) calculated for 4-mm-diameter rods within linearity and uniform activity rod phantoms were near unity (0.97 ± 0.06 and 1.03 ± 0.03, respectively). Intratumoral uptake patterns for both 18F-FDG and a 64Cu-antibody acquired using the PET/MRI scanner and small-animal PET were highly correlated with autoradiography (r > 0.99) and with each other (r = 0.97 ± 0.01). On the basis of these data, we performed a preliminary study comparing

  15. Reproducibility of Quantitative Brain Imaging Using a PET-Only and a Combined PET/MR System

    DEFF Research Database (Denmark)

    Lassen, Martin L; Muzik, Otto; Beyer, Thomas

    2017-01-01

    observed for kinetic parameters derived from emission data obtained from PET/MR and PET-only imaging due to different standard AC methods employed. Therefore, a transfer of imaging protocols from PET-only to PET/MR systems is not straightforward without application of proper correction methods...

  16. Comparing life cycle energy and GHG emissions of bio-based PET, recycled PET, PLA and man-made cellulosics

    NARCIS (Netherlands)

    Shen, L.; Worrell, E.; Patel, M.K.

    2012-01-01

    The purpose of this paper is to review the environmental profiles of petrochemical PET, (partially) bio-based PET, recycled PET, and recycled (partially) bio-based PET, and compare them with other bio-based materials, namely PLA (polylactic acid, a bio-based polyester) and man-made cellulose

  17. Attenuation correction for small animal PET tomographs

    Energy Technology Data Exchange (ETDEWEB)

    Chow, Patrick L [David Geffen School of Medicine at UCLA, Crump Institute for Molecular Imaging, University of California, 700 Westwood Plaza, Los Angeles, CA 90095 (United States); Rannou, Fernando R [Departamento de Ingenieria Informatica, Universidad de Santiago de Chile (USACH), Av. Ecuador 3659, Santiago (Chile); Chatziioannou, Arion F [David Geffen School of Medicine at UCLA, Crump Institute for Molecular Imaging, University of California, 700 Westwood Plaza, Los Angeles, CA 90095 (United States)

    2005-04-21

    Attenuation correction is one of the important corrections required for quantitative positron emission tomography (PET). This work will compare the quantitative accuracy of attenuation correction using a simple global scale factor with traditional transmission-based methods acquired either with a small animal PET or a small animal x-ray computed tomography (CT) scanner. Two phantoms (one mouse-sized and one rat-sized) and two animal subjects (one mouse and one rat) were scanned in CTI Concorde Microsystem's microPET (registered) Focus{sup TM} for emission and transmission data and in ImTek's MicroCAT{sup TM} II for transmission data. PET emission image values were calibrated against a scintillation well counter. Results indicate that the scale factor method of attenuation correction places the average measured activity concentration about the expected value, without correcting for the cupping artefact from attenuation. Noise analysis in the phantom studies with the PET-based method shows that noise in the transmission data increases the noise in the corrected emission data. The CT-based method was accurate and delivered low-noise images suitable for both PET data correction and PET tracer localization.

  18. The impact of owner age on companionship with virtual pets

    OpenAIRE

    Lawson, Shaun W.; Chesney, Thomas

    2007-01-01

    This paper focuses on issues of interaction with a particular type of mobile information system – virtual pets. It examines the impact of owner age on companionship with virtual pets, and tests the hypothesis that younger virtual pet owners will experience closer companionship with their virtual pet than older owners. This is in response to the marketing stance adopted by virtual pet manufacturers who clearly target younger people as the main consumers of their products. The hypothesis was te...

  19. Pet Ownership and Evacuation Prior to Hurricane Irene

    OpenAIRE

    Hunt, Melissa G.; Bogue, Kelsey; Rohrbaugh, Nick

    2012-01-01

    Simple Summary Ninety pet owners and 27 non-pet owners who lived in mandatory evacuation zones during the 2011 Hurricane Irene were surveyed about whether or not they evacuated and about their experiences during the hurricane. Although pet-ownership was not statistically associated with evacuation failure, many pet owners who chose not to evacuate still claimed that they did not evacuate because of difficulties with evacuating their pet. These findings suggest that more work needs to be done ...

  20. Practical use and implementation of PET in children in a hospital PET centre

    Energy Technology Data Exchange (ETDEWEB)

    Borgwardt, Lise; Larsen, Helle Jung; Pedersen, Kate; Hoejgaard, Liselotte [Department of Clinical Physiology, Nuclear Medicine and PET, University Hospital of Copenhagen, Rigshospitalet, Blegdamsvej 9, 2100, Copenhagen (Denmark)

    2003-10-01

    Children are not just small adults - they differ in their psychology, normal physiology and pathophysiology, and various aspects should be considered when planning a positron emission tomography (PET) scan in a child. PET in children is a growing area, and this article describes the practical use and implementation of PET in children in a hospital PET centre. It is intended to be of use to nuclear medicine departments implementing or starting to implement PET scans in children. Topics covered are: dealing with children, dosimetry, organisation within the department and relations with other departments, preparation of the child (provision of information to the child and parents and the fasting procedure), the imaging procedure (resting, tracer injection, positioning, sedation and bladder emptying) and pitfalls in the interpretation of PET scans in children, including experiences with telemedicine. (orig.)

  1. Molecular Imaging in Breast Cancer: From Whole-Body PET/CT to Dedicated Breast PET

    Directory of Open Access Journals (Sweden)

    B. B. Koolen

    2012-01-01

    Full Text Available Positron emission tomography (PET, with or without integrated computed tomography (CT, using 18F-fluorodeoxyglucose (FDG is based on the principle of elevated glucose metabolism in malignant tumors, and its use in breast cancer patients is frequently being investigated. It has been shown useful for classification, staging, and response monitoring, both in primary and recurrent disease. However, because of the partial volume effect and limited resolution of most whole-body PET scanners, sensitivity for the visualization of small tumors is generally low. To improve the detection and quantification of primary breast tumors with FDG PET, several dedicated breast PET devices have been developed. In this nonsystematic review, we shortly summarize the value of whole-body PET/CT in breast cancer and provide an overview of currently available dedicated breast PETs.

  2. Evaluating pet foods: how confident are you when you recommend a commercial pet food?

    Science.gov (United States)

    Zicker, Steven C

    2008-08-01

    The safety, adequacy, and efficacy of pet foods are important considerations for veterinarians and consumers. Manufacturers of pet foods in the United States are required to comply with multiple regulations from a variety of governmental and state agencies to market foods in the public sector. However, consumers and veterinarians may not be aware of the multiple systems in place that help ensure the safety and adequacy of foods for their pets. Since the veterinarian occupies a key role to make recommendations to consumers regarding pet foods, it is the purpose of this article to review the processes of pet food manufacturing, as well as the processes that have been developed to help ensure safety and adequacy of pet foods in the United States.

  3. Practical use and implementation of PET in children in a hospital PET centre

    DEFF Research Database (Denmark)

    Borgwardt, Lise; Larsen, Helle Jung; Pedersen, Kate

    2003-01-01

    Children are not just small adults-they differ in their psychology, normal physiology and pathophysiology, and various aspects should be considered when planning a positron emission tomography (PET) scan in a child. PET in children is a growing area, and this article describes the practical use...... and implementation of PET in children in a hospital PET centre. It is intended to be of use to nuclear medicine departments implementing or starting to implement PET scans in children. Topics covered are: dealing with children, dosimetry, organisation within the department and relations with other departments......, preparation of the child (provision of information to the child and parents and the fasting procedure), the imaging procedure (resting, tracer injection, positioning, sedation and bladder emptying) and pitfalls in the interpretation of PET scans in children, including experiences with telemedicine....

  4. PET/CT with intravenous contrast can be used for PET attenuation correction in cancer patients

    DEFF Research Database (Denmark)

    Berthelsen, A K; Holm, S; Loft, A

    2005-01-01

    correction, but this may result in a bias in the attenuation factors. The clinical significance of this bias has not been established. Our aim was to perform a prospective clinical study where each patient had CT performed with and without IV contrast agent to establish whether PET/CT with IV contrast can...... be used for PET attenuation without reducing the clinical value of the PET scan. METHODS: A uniform phantom study was used to document that the PET acquisition itself is not significantly influenced by the presence of IV contrast medium. Then, 19 patients referred to PET/CT with IV contrast underwent CT...... comparison of standard uptake value (SUV) was performed, and SUVs in tumour, in non-tumour tissue and in the subclavian vein were calculated. Clinical evaluation of the number and location of lesions on all PET/CT scans was performed twice, blinded and in a different random order, by two independent nuclear...

  5. The heritage of radiotracers for PET

    Energy Technology Data Exchange (ETDEWEB)

    Fowler, J.S.; Wolf, A.P.

    1988-05-01

    The history of PET research clearly demonstrates that it is advances in chemistry coupled with a detailed examination of the biochemistry of new radiotracers which has allowed the PET method to be applied to new areas of biology and medicine. Radiotracers whose regional distribution reflects glucose metabolism, neutrotransmitter activity and enzyme activity have all required the development of rapid synthetic methods for the radiotracers themselves and the characterization of their biochemical behavior. This article traces some of the advances in the production of labeled precursors and in radiotracer synthesis and evaluation which have shaped the rapidly expanding application of PET to problems in the neurosciences, in cardiology and in oncology. 54 refs.

  6. Imaging neuronal pathways with 52Mn PET

    DEFF Research Database (Denmark)

    Napieczynska, Hanna; Severin, Gregory; Fonslet, Jesper

    2017-01-01

    tomography (PET) neuronal tract tracer. We used 52Mn for imaging dopaminergic pathways after a unilateral injection into the ventral tegmental area (VTA), as well as the striatonigral pathway after an injection into the dorsal striatum (STR) in rats. Furthermore, we tested potentially noxious effects...... of the radioactivity dose with a behavioral test and histological staining. 24 h after 52Mn administration, the neuronal tracts were clearly visible in PET images and statistical analysis confirmed the observed distribution of the tracer. We noticed a behavioral impairment in some animals treated with 170 kBq of 52Mn...... for PET imaging....

  7. The Heritage of Radiotracers for PET

    Science.gov (United States)

    Fowler, J. S.; Wolf, A. P.

    1988-05-01

    The history of PET research clearly demonstrates that it is advances in chemistry coupled with a detailed examination of the biochemistry of new radiotracers which has allowed the PET method to be applied to new areas of biology and medicine. Radiotracers whose regional distribution reflects glucose metabolism, neutrotransmitter activity and enzyme activity have all required the development of rapid synthetic methods for the radiotracers themselves and the characterization of their biochemical behavior. This article traces some of the advances in the production of labeled precursors and in radiotracer synthesis and evaluation which have shaped the rapidly expanding application of PET to problems in the neurosciences, in cardiology and in oncology.

  8. Quantitative carotid PET/MR imaging: clinical evaluation of MR-Attenuation correction versus CT-Attenuation correction in 18F-FDG PET/MR emission data and comparison to PET/CT

    OpenAIRE

    Bini, Jason; Robson, Philip M.; Calcagno, Claudia; Eldib, Mootaz; Fayad, Zahi A.

    2015-01-01

    Current PET/MR systems employ segmentation of MR images and subsequent assignment of empirical attenuation coefficients for quantitative PET reconstruction. In this study we examine the differences in the quantification of 18F-FDG uptake in the carotid arteries between PET/MR and PET/CT scanners. Five comparisons were performed to asses differences in PET quantification: i) PET/MR MR-based AC (MRAC) versus PET/MR CTAC, ii) PET/MR MRAC versus PET/CT, iii) PET/MR MRAC with carotid coil versus P...

  9. Fat-constrained 18F-FDG PET reconstruction in hybrid PET/MR imaging.

    Science.gov (United States)

    Prevrhal, Sven; Heinzer, Susanne; Wülker, Christian; Renisch, Steffen; Ratib, Osman; Börnert, Peter

    2014-10-01

    Fusion of information from PET and MR imaging can increase the diagnostic value of both modalities. This work sought to improve (18)F FDG PET image quality by using MR Dixon fat-constrained images to constrain PET image reconstruction to low-fat regions, with the working hypothesis that fatty tissue metabolism is low in glucose consumption. A novel constrained PET reconstruction algorithm was implemented via a modification of the system matrix in list-mode time-of-flight ordered-subsets expectation maximization reconstruction, similar to the way time-of-flight weighting is incorporated. To demonstrate its use in PET/MR imaging, we modeled a constraint based on fat/water-separating Dixon MR images that shift activity away from regions of fat tissue during PET image reconstruction. PET and MR imaging scans of a modified National Electrical Manufacturers Association/International Electrotechnical Commission body phantom simulating body fat/water composition and in vivo experiments on 2 oncology patients were performed on a commercial time-of-flight PET/MR imaging system. Fat-constrained PET reconstruction visibly and quantitatively increased resolution and contrast between high-uptake and fatty-tissue regions without significantly affecting the images in nonfat regions. The incorporation of MR tissue information, such as fat, in image reconstruction can improve the quality of PET images. The combination of a variety of potential other MR tissue characteristics with PET represents a further justification for merging MR data with PET data in hybrid systems. © 2014 by the Society of Nuclear Medicine and Molecular Imaging, Inc.

  10. Simultaneous trimodal PET-MR-EEG imaging: Do EEG caps generate artefacts in PET images?

    OpenAIRE

    Ravichandran Rajkumar; Elena Rota Kops; Jörg Mauler; Lutz Tellmann; Christoph Lerche; Hans Herzog; N Jon Shah; Irene Neuner

    2017-01-01

    Trimodal simultaneous acquisition of positron emission tomography (PET), magnetic resonance imaging (MRI), and electroencephalography (EEG) has become feasible due to the development of hybrid PET-MR scanners. To capture the temporal dynamics of neuronal activation on a millisecond-by-millisecond basis, an EEG system is appended to the quantitative high resolution PET-MR imaging modality already established in our institute. One of the major difficulties associated with the development of sim...

  11. Bacteriophages safely reduce Salmonella contamination in pet food and raw pet food ingredients

    OpenAIRE

    Soffer, Nitzan; Abuladze, Tamar; Woolston, Joelle; Li, Manrong; Hanna, Leigh Farris; Heyse, Serena; Charbonneau, Duane; Sulakvelidze, Alexander

    2016-01-01

    Contamination of pet food with Salmonella is a serious public health concern, and several disease outbreaks have recently occurred due to human exposure to Salmonella tainted pet food. The problem is especially challenging for raw pet foods (which include raw meats, seafood, fruits, and vegetables). These foods are becoming increasingly popular because of their nutritional qualities, but they are also more difficult to maintain Salmonella-free because they lack heat-treatment. Among various m...

  12. PET/CT and PET/MRI in head and neck malignancy.

    Science.gov (United States)

    Szyszko, T A; Cook, G J R

    2018-01-01

    Combined 2-[18F]-fluoro-2-deoxy-d-glucose (FDG) positron-emission tomography (PET)/computed tomography (CT) has an established role in the staging of difficult cases of head and neck (HN) squamous cell carcinoma (SCC), looking for an unknown primary, assessing response post-chemotherapy at 3-6 months, and differentiating relapse from treatment effects in patients suspected to have tumour recurrence. The PET NECK trial, comparing PET/CT surveillance versus neck dissection in advanced head and neck cancer showed survival was similar among patients who underwent PET/CT-guided surveillance and those who underwent planned neck dissection, but surveillance was more cost-effective. There is growing interest in the use of hypoxia PET tracers, especially in targeting radiotherapy, where the radiotherapy dose can be boosted in regions of hypoxia; the use of 68Ga peptide tracers in neuroendocrine malignancy and also in the growing field of combined PET/magnetic resonance imaging (MRI). PET/MRI has the advantage of increased anatomical detail and radiation dose reduction combined with the molecular and metabolic data from PET, although PET/CT has the advantage in better sensitivity for imaging lung metastases. Thus far, there is good agreement between PET/CT and PET/MRI with high correlation between semi-quantitative measurements in primary, nodal, osseous, and soft-tissue lesions imaging. PET/MRI may indeed provide greater accuracy than the currently available imaging procedures in the staging and later treatment response evaluation in HNSCC. Copyright © 2017. Published by Elsevier Ltd.

  13. The spatial distribution of pet dogs and pet cats on the island of Ireland

    OpenAIRE

    Downes, Martin J; Clegg, Tracy A; Collins, Daniel M; McGrath, Guy; More, Simon J

    2011-01-01

    Abstract Background There is considerable international research regarding the link between human demographics and pet ownership. In several international studies, pet ownership was associated with household demographics including: the presence of children in the household, urban/rural location, level of education and age/family structure. What is lacking across all these studies, however, is an understanding of how these pets are spatially distributed throughout the regions under study. This...

  14. Development of a PET Scanner for Simultaneously Imaging Small Animals with MRI and PET

    Directory of Open Access Journals (Sweden)

    Christopher J Thompson

    2014-08-01

    Full Text Available Recently, positron emission tomography (PET is playing an increasingly important role in the diagnosis and staging of cancer. Combined PET and X-ray computed tomography (PET-CT scanners are now the modality of choice in cancer treatment planning. More recently, the combination of PET and magnetic resonance imaging (MRI is being explored in many sites. Combining PET and MRI has presented many challenges since the photo-multiplier tubes (PMT in PET do not function in high magnetic fields, and conventional PET detectors distort MRI images. Solid state light sensors like avalanche photo-diodes (APDs and more recently silicon photo-multipliers (SiPMs are much less sensitive to magnetic fields thus easing the compatibility issues. This paper presents the results of a group of Canadian scientists who are developing a PET detector ring which fits inside a high field small animal MRI scanner with the goal of providing simultaneous PET and MRI images of small rodents used in pre-clinical medical research. We discuss the evolution of both the crystal blocks (which detect annihilation photons from positron decay and the SiPM array performance in the last four years which together combine to deliver significant system performance in terms of speed, energy and timing resolution.

  15. Dedicated brain PET system of PET/MR for brain research

    Energy Technology Data Exchange (ETDEWEB)

    Cheng, Li; Liu, Yaqiang; Ma, Tianyu; Wang, Shi; Wei, Qingyang; Xu, Tianpeng [Institute of Medical Physics, Department of Engineering Physics, Tsinghua University, Beijing (China)

    2015-05-18

    This work is to replace PET ring in human brain PET/MR system with a dedicated wearable PET insert, aimed at improving both patient feasibility and system performance for brain imaging. The designed PET/MR system includes two parts: the inside parts, including a radio frequency (RF) coil and PET ring, are mounted on patient’s head, and the outside part, a MR imager, is dependent of patient. The RF coil is the innermost layer, surrounded by an outer PET-ring layer. They are supported by a MRcompatible structure. And both RF coil and PET detectors are placed inside a standard clinical 3-T MR imager. From the design of the system we can infer that some advantages can be achieved. First, high sensitivity will be achieved with the same amount crystals as the PET ring is more close to region-of-interest area, at a reduced cost. Second, by using a 2-layer depth of interaction (DOI) detector, the parallax effect can be minimized. The resolution will benefit from short positron range caused by magnetic field and smaller ring diameter will also reduce the effect of non-collinearity. Thirdly, as the PET ring is mounted on head, impact of patient motion will be reduced.

  16. APD-based PET detector for simultaneous PET/MR imaging

    Energy Technology Data Exchange (ETDEWEB)

    Grazioso, Ronald [Siemens Molecular Imaging, Knoxville, TN (United States)]. E-mail: ron.grazioso@siemens.com; Zhang, Nan [Siemens Molecular Imaging, Knoxville, TN (United States); Corbeil, James [Siemens Molecular Imaging, Knoxville, TN (United States); Schmand, Matthias [Siemens Molecular Imaging, Knoxville, TN (United States); Ladebeck, Ralf [Siemens AG Medical Solutions MR, Erlangen (Germany); Vester, Markus [Siemens AG Medical Solutions MR, Erlangen (Germany); Schnur, Guenter [Siemens AG Medical Solutions MR, Erlangen (Germany); Renz, Wolfgang [Siemens AG Medical Solutions MR, Erlangen (Germany); Fischer, Hubertus [Siemens AG Medical Solutions MR, Erlangen (Germany)

    2006-12-20

    Two, APD-based, PET modules have been evaluated for use in combined PET/MR imaging. Each module consists of 4 independent, optically isolated detectors. Each detector consists of an 8x8 array of 2x2x20 mm LSO crystals read out by a 2x2 array of 5x5 mm Hamamatsu S8664-55 APDs. The average crystal energy resolution and time resolution (against a plastic scintillator on a PMT) of the detectors was 17% and 1.8 ns, respectively. The modules were positioned in the tunnel of a 1.5 T Siemens Symphony MR scanner. The presence of the PET modules decreased the MR signal-to-noise ratio by about 15% but no image interference was observed. The gradient and RF pulse sequences of the MR produced adverse effects on the PET event signals. These high-frequency pulses did not affect the true PET events but did increase the dead time of the PET system. Simultaneous, artifact-free, images were acquired with the PET and MR system using a small Derenzo phantom. These results show that APD-based PET detectors can be used for a high-resolution and cost-effective integrated PET/MR system.

  17. APD-based PET detector for simultaneous PET/MR imaging

    Science.gov (United States)

    Grazioso, Ronald; Zhang, Nan; Corbeil, James; Schmand, Matthias; Ladebeck, Ralf; Vester, Markus; Schnur, Günter; Renz, Wolfgang; Fischer, Hubertus

    2006-12-01

    Two, APD-based, PET modules have been evaluated for use in combined PET/MR imaging. Each module consists of 4 independent, optically isolated detectors. Each detector consists of an 8×8 array of 2×2×20 mm LSO crystals read out by a 2×2 array of 5×5 mm Hamamatsu S8664-55 APDs. The average crystal energy resolution and time resolution (against a plastic scintillator on a PMT) of the detectors was 17% and 1.8 ns, respectively. The modules were positioned in the tunnel of a 1.5 T Siemens Symphony MR scanner. The presence of the PET modules decreased the MR signal-to-noise ratio by about 15% but no image interference was observed. The gradient and RF pulse sequences of the MR produced adverse effects on the PET event signals. These high-frequency pulses did not affect the true PET events but did increase the dead time of the PET system. Simultaneous, artifact-free, images were acquired with the PET and MR system using a small Derenzo phantom. These results show that APD-based PET detectors can be used for a high-resolution and cost-effective integrated PET/MR system.

  18. Motion Correction of Whole-Body PET Data with a Joint PET-MRI Registration Functional

    OpenAIRE

    Fieseler, M. (Michael); Gigengack, F. (Fabian); Jiang, X.; Schäfers, K.P.

    2014-01-01

    Respiratory motion is known to degrade image quality in PET imaging. The necessary acquisition time of several minutes per bed position will inevitably lead to a blurring effect due to organ motion. A lot of research has been done with regards to motion correction of PET data. As full-body PET-MRI became available recently, the anatomical data provided by MRI is a promising source of motion information. Current PET-MRI-based motion correction approaches, however, do not take into account the ...

  19. Is non-attenuation-corrected PET inferior to body attenuation-corrected PET or PET/CT in lung cancer?

    Energy Technology Data Exchange (ETDEWEB)

    Maintas, Dimitris [CMN, Hopital Pneumocardiologique de Lyon, 69394 Lyon Cedex (France)]. E-mail: maintas@otenet.gr; Houzard, Claire [CMN, Hopital Pneumocardiologique de Lyon, 69394 Lyon Cedex (France); Ksyar, Rachid [CMN, Hopital Pneumocardiologique de Lyon, 69394 Lyon Cedex (France); Mognetti, Thomas [Anticancer Center Leon Berard, Nuclear Medicine Department, Lyon (France); Maintas, Catherine [Institute of Isotopic Studies, Distomou 5-7, Maroussi (Greece); Scheiber, Christian [CMN, Hopital Pneumocardiologique de Lyon, 69394 Lyon Cedex (France); Itti, Roland [CMN, Hopital Pneumocardiologique de Lyon, 69394 Lyon Cedex (France)

    2006-12-20

    It is considered that one of the great strengths of PET imaging is the ability to correct for body attenuation. This enables better lesion uptake quantification and quality of PET images. The aim of this work is to compare the sensitivity of non-attenuation-corrected (NAC) PET images, the gamma photons (GPAC) and CT attenuation-corrected (CTAC) images in detecting and staging of lung cancer. We have studied 66 patients undergoing PET/CT examinations for detecting and staging NSC lung cancer. The patients were injected with 18-FDG; 5 MBq/kg under fasting conditions and examination was started 60 min later. Transmission data were acquired by a spiral CT X-ray tube and by gamma photons emitting Cs-137l source and were used for the patient body attenuation correction without correction for respiratory motion. In 55 of 66 patients we performed both attenuation correction procedures and in 11 patients only CT attenuation correction. In seven patients with solitary nodules PET was negative and in 59 patients with lung cancer PET/CT was positive for pulmonary or other localization. In the group of 55 patients we found 165 areas of focal increased 18-FDG uptake in NAC, 165 in CTAC and 164 in GPAC PET images.In the patients with only CTAC we found 58 areas of increased 18-FDG uptake on NAC and 58 areas lesions on CTAC. In the patients with positive PET we found 223 areas of focal increased uptake in NAC and 223 areas in CTAC images. The sensitivity of NAC was equal to the sensitivity of CTAC and GPAC images. The visualization of peripheral lesions was better in NAC images and the lesions were better localized in attenuation-corrected images. In three lesions of the thorax the localization was better in GPAC and fused images than in CTAC images.

  20. Evaluation of the PET component of simultaneous [{sup 18}F]choline PET/MRI in prostate cancer: comparison with [{sup 18}F]choline PET/CT

    Energy Technology Data Exchange (ETDEWEB)

    Wetter, Axel; Lipponer, Christine; Nensa, Felix; Altenbernd, Jens-Christian; Schlosser, Thomas; Lauenstein, Thomas [University Hospital Essen, Department of diagnostic and interventional Radiology and Neuroradiology, Essen (Germany); Heusch, Philipp [University Dusseldorf, Medical Faculty, Department of diagnostic and interventional Radiology, Dusseldorf (Germany); Ruebben, Herbert [University Hospital Essen, Department of Urology and pediatric Urology, Essen (Germany); Bockisch, Andreas; Poeppel, Thorsten; Nagarajah, James [University Hospital Essen, Department of Nuclear Medicine, Essen (Germany)

    2014-01-15

    The aim of this study was to evaluate the positron emission tomography (PET) component of [{sup 18}F]choline PET/MRI and compare it with the PET component of [{sup 18}F]choline PET/CT in patients with histologically proven prostate cancer and suspected recurrent prostate cancer. Thirty-six patients were examined with simultaneous [{sup 18}F]choline PET/MRI following combined [{sup 18}F]choline PET/CT. Fifty-eight PET-positive lesions in PET/CT and PET/MRI were evaluated by measuring the maximum and mean standardized uptake values (SUV{sub max} and SUV{sub mean}) using volume of interest (VOI) analysis. A scoring system was applied to determine the quality of the PET images of both PET/CT and PET/MRI. Agreement between PET/CT and PET/MRI regarding SUV{sub max} and SUV{sub mean} was tested using Pearson's product-moment correlation and Bland-Altman analysis. All PET-positive lesions that were visible on PET/CT were also detectable on PET/MRI. The quality of the PET images was comparable in both groups. Median SUV{sub max} and SUV{sub mean} of all lesions were significantly lower in PET/MRI than in PET/CT (5.2 vs 6.1, p < 0.05 and 2.0 vs 2.6, p < 0.001, respectively). Pearson's product-moment correlation indicated highly significant correlations between SUV{sub max} of PET/CT and PET/MRI (R = 0.86, p < 0.001) as well as between SUV{sub mean} of PET/CT and PET/MRI (R = 0.81, p < 0.001). Bland-Altman analysis revealed lower and upper limits of agreement of -2.77 to 3.64 between SUV{sub max} of PET/CT vs PET/MRI and -1.12 to +2.23 between SUV{sub mean} of PET/CT vs PET/MRI. PET image quality of PET/MRI was comparable to that of PET/CT. A highly significant correlation between SUV{sub max} and SUV{sub mean} was found. Both SUV{sub max} and SUV{sub mean} were significantly lower in [{sup 18}F]choline PET/MRI than in [{sup 18}F]choline PET/CT. Differences of SUV{sub max} and SUV{sub mean} might be caused by different techniques of attenuation correction

  1. Molecular Imaging Challenges With PET

    CERN Document Server

    Lecoq, P

    2010-01-01

    The future trends in molecular imaging and associated challenges for in-vivo functional imaging are illustrated on the basis of a few examples, such as atherosclerosis vulnerable plaques imaging or stem cells tracking. A set of parameters are derived to define the specifications of a new generation of in-vivo imaging devices in terms of sensitivity, spatial resolution and signal-to-noise ratio. The limitations of strategies used in present PET scanners are discussed and new approaches are proposed taking advantage of recent progress on materials, photodetectors and readout electronics. A special focus is put on metamaterials, as a new approach to bring more functionality to detection devices. It is shown that the route is now open towards a fully digital detector head with very high photon counting capability over a large energy range, excellent timing precision and possibility of imaging the energy deposition process.

  2. Desvulcanização do resíduo de terpolímero de etileno-propileno-dieno (EPDM-r por micro-ondas Devulcanization of ethylene-propylene-diene polymer residues (EPDM-r by microwaves

    Directory of Open Access Journals (Sweden)

    Vinicius Pistor

    2010-09-01

    Full Text Available Elastômeros vulcanizados são materiais comumente empregados em diversas aplicações, como nas indústrias automotiva e calçadista. Neste trabalho, aparas do terpolímero de etileno-propileno-dieno (EPDM-r provenientes da indústria automotiva foram submetidas a micro-ondas durante diferentes tempos de exposição (2-5 min. Após a desvulcanização, as amostras foram caracterizadas por teor de gel, calorimetria exploratória diferencial (DSC e energias de ativação de degradação (Ea determinadas por análise termogravimétrica (TGA. O comportamento de degradação apresentou composição do EPDM-r condizente com a literatura. A análise de teor de gel demonstrou que o EPDM-r foi desvulcanizado quando exposto às micro-ondas por 5 minutos. As análises de DSC não indicaram modificações significativas nas amostras estudadas, e o estudo de Ea mostrou que os aditivos encontrados na composição do EPDM-r influenciam na eficiência do método de regeneração por micro-ondas.Vulcanized elastomers are materials commonly used in several applications, such as automotive and footwear industries. In this study, scraps of ethylene-propylene-diene terpolymer (EPDM-r from the automotive industry were exposed to microwaves during different periods (2-5 min. After devulcanization, the samples were characterized by gel content, differential scanning calorimetry (DSC and activation energy of degradation (Ea determined by thermogravimetric analysis (TGA. The degradation behavior of EPDM-r was consistent with the literature. The gel content analysis showed that the EPDM-r was devulcanized only at 5 minutes of exposure to the microwaves. DSC analysis demonstrated no significant changes in the samples, and the Ea results confirmed that the additives found in the composition of the EPDM-r affect the efficiency of the regeneration method.

  3. Don't Just Pet Your Chia.

    Science.gov (United States)

    Hershey, David R.

    1995-01-01

    Presents ways to use ChiaPets to link biology-related topics such as taxonomy, morphology, ethnobotany, economic botany, hydroponics, salinity, photomorphogenesis, and phototropism with food and fertilizer chemistry, mathematics, art, and history. (MKR)

  4. Therapy assessment in multiple myeloma with PET.

    Science.gov (United States)

    Nanni, Cristina; Zamagni, Elena

    2017-08-01

    Multiple myeloma is a plasma cell dyscrasia producing bone lytic lesions. In recent years, a wide spectrum of therapeutic approaches are available to treat the disease: an accurate therapy assessment has, therefore, become of utmost importance. In this field, imaging is becoming a cornerstone, especially in association with clinical parameters. Among imaging procedures, FDG PET/CT is recognized to provide reliable information, achieved in a very safe and fast procedure.  The literature has produced very concordant results from different groups assessing the value of FDG PET/CT as a prognostic factor in general and in therapy assessment, but some issues remain regarding a standardization of image interpretation especially in borderline cases. So far, no data regarding nor other imaging compounds and the use of hybrid tomographs PET/MR are available to define therapy assessment in PET.

  5. Autism spectrum disorder and pet therapy.

    Science.gov (United States)

    Siewertsen, Caitlin M; French, Emma D; Teramoto, Masaru

    2015-01-01

    Autism Spectrum Disorder (ASD) encompasses a wide range of social and mental afflictions that are difficult to treat. Due to a lack of established treatments for ASD, alternative therapies have been the primary form of intervention. One of these alternatives is pet therapy, a field that has experienced growing interest and has recently accumulated studies that investigate its efficacy. This article reviews and summarizes that effectiveness as well as the findings and limitations associated with pet therapy for ASD. The majority of research on ASD and pet therapy has examined children and has primarily used dogs and horses for therapy. Studies have shown positive effects for the therapy, including high satisfaction rates among the participants' families. Major limitations of studies in the current literature include the lack of control groups and small sample sizes. Future research should incorporate better study designs and large samples to validate pet therapy as an appropriate treatment for ASD.

  6. FDG PET/CT in cancer

    DEFF Research Database (Denmark)

    Petersen, Henrik; Holdgaard, Paw Christian; Madsen, Poul Henning

    2016-01-01

    use of PET/CT in the RSD with these recommendations. This article summarizes the results. METHODS: A Work Group appointed a professional Subgroup which made Clinician Groups conduct literature reviews on six selected cancers responsible for 5,768 (62.6 %) of 9,213 PET/CT scans in the RSD in 2012......-recommendable" indications, respectively. RESULTS: Of 11,729 citations, 1,729 were considered for review, and 204 were included. The evidence suggested usefulness of PET/CT in lung, lymphoma, melanoma, head and neck, and colorectal cancers, whereas evidence was sparse in gynaecological cancers. The agreement between actual...... use of PET/CT and literature-based recommendations was high in the first five mentioned cancers in that 96.2 % of scans were made for grade A or B indications versus only 22.2 % in gynaecological cancers. CONCLUSION: Evidence-based usefulness was reported in five of six selected cancers; evidence...

  7. Pathophysiology of movement disorders studied using PET

    NARCIS (Netherlands)

    Leenders, KL

    1997-01-01

    PET radiotracer methods can measure various biochemical features of brain tissue in the living human brain. Here, local brain energy consumption and striatal dopaminergic function will be discussed in the light of the . neurodegenerative processes underlying Parkinson's disease. Particularly,

  8. PET/MR Imaging in Vascular Disease

    DEFF Research Database (Denmark)

    Ripa, Rasmus Sejersten; Pedersen, Sune Folke; Kjær, Andreas

    2016-01-01

    For imaging of atherosclerotic disease, lumenography using computed tomography, ultrasonography, or invasive angiography is still the backbone of evaluation. However, these methods are less effective to predict the likelihood of future thromboembolic events caused by vulnerability of plaques. PET...

  9. Therapy assessment in multiple myeloma with PET

    Energy Technology Data Exchange (ETDEWEB)

    Nanni, Cristina [Medicina Nucleare Metropolitana di Bologna, Bologna (Italy); Zamagni, Elena [Bologna University School of Medicine, Seragnoli Institute of Hematology, Bologna (Italy)

    2017-08-15

    Multiple myeloma is a plasma cell dyscrasia producing bone lytic lesions. In recent years, a wide spectrum of therapeutic approaches are available to treat the disease: an accurate therapy assessment has, therefore, become of utmost importance. In this field, imaging is becoming a cornerstone, especially in association with clinical parameters. Among imaging procedures, FDG PET/CT is recognized to provide reliable information, achieved in a very safe and fast procedure. The literature has produced very concordant results from different groups assessing the value of FDG PET/CT as a prognostic factor in general and in therapy assessment, but some issues remain regarding a standardization of image interpretation especially in borderline cases. So far, no data regarding nor other imaging compounds and the use of hybrid tomographs PET/MR are available to define therapy assessment in PET. (orig.)

  10. Dynamic PET denoising with HYPR processing

    National Research Council Canada - National Science Library

    Christian, Bradley T; Vandehey, Nicholas T; Floberg, John M; Mistretta, Charles A

    2010-01-01

    HighlY constrained backPRojection (HYPR) is a promising image-processing strategy with widespread application in time-resolved MRI that is also well suited for PET applications requiring time series data...

  11. PET and PET/CT imaging for the earliest detection and treatment of colorectal carcinoma

    Directory of Open Access Journals (Sweden)

    Kevin Carter

    2005-10-01

    Full Text Available Approximately 150,000 new cases of colorectal cancer are diagnosed each year with the life time risk of developing colon caner in developed nations being 4.6% in men and 3.2% in women. Screening patients is essential early detection of colon carcinoma to aid in complete resection. Unfortunately current screening methods carry with them poor patient compliance. PET and PET/CT may be a significant part of this screening solution. The authors reviewed and analyzed the English language articles and case reports identified on Medline during the last 10 years. PET and PET/CT results for colorectal carcinoma were tabulated and presented for the fifth Scientific Meeting of the Brazilian Society of Nuclear Biosciences. Though most studies have been retrospective analysis in using PET for staging for other malignant processes the cases that have identified additional uptake in the colon are important. The accuracy when utilizing PET and PET/CT in this screening method has a sensitivity between 65 and 90% with a specificity of 84 to 90% and a positive predictive value 71 to 78%. Early stages of malignancies and pre-cancerous polyps avidly accumulates F-18 Deoxyflouro glucose allowing us to conclude that whole body PET and PET/CT is an essential component in the work up, staging or treatment monitoring in colon carcinoma. We have to continue to accumulate data for possible introduction for whole body PET and PET/CT scanning for colon carcinoma and precancerous polyps.Aproximadamente, 150 000 novos casos de câncer coloretal são diagnosticados, anualmente, em países em desenvolvimento. Destes, 4,6% em homens e 3,2% em mulheres. A triagem de pacientes é essencial na detecção precoce do carcinoma de colon para ajudar na completa ressecção. Infelizmente, os métodos de exame atualmente disponíveis contam com uma baixa adesão dos pacientes. Parte significativa da solução desse problema pode estar no uso de PET e PET/CT. Os autores revisaram e

  12. Dynamic neurotransmitter interactions measured with PET

    Energy Technology Data Exchange (ETDEWEB)

    Schiffer, W.K.; Dewey, S.L.

    2001-04-02

    Positron emission tomography (PET) has become a valuable interdisciplinary tool for understanding physiological, biochemical and pharmacological functions at a molecular level in living humans, whether in a healthy or diseased state. The utility of tracing chemical activity through the body transcends the fields of cardiology, oncology, neurology and psychiatry. In this, PET techniques span radiochemistry and radiopharmaceutical development to instrumentation, image analysis, anatomy and modeling. PET has made substantial contributions in each of these fields by providing a,venue for mapping dynamic functions of healthy and unhealthy human anatomy. As diverse as the disciplines it bridges, PET has provided insight into an equally significant variety of psychiatric disorders. Using the unique quantitative ability of PET, researchers are now better able to non-invasively characterize normally occurring neurotransmitter interactions in the brain. With the knowledge that these interactions provide the fundamental basis for brain response, many investigators have recently focused their efforts on an examination of the communication between these chemicals in both healthy volunteers and individuals suffering from diseases classically defined as neurotransmitter specific in nature. In addition, PET can measure the biochemical dynamics of acute and sustained drug abuse. Thus, PET studies of neurotransmitter interactions enable investigators to describe a multitude of specific functional interactions in the human brain. This information can then be applied to understanding side effects that occur in response to acute and chronic drug therapy, and to designing new drugs that target multiple systems as opposed to single receptor types. Knowledge derived from PET studies can be applied to drug discovery, research and development (for review, see (Fowler et al., 1999) and (Burns et al., 1999)). Here, we will cover the most substantial contributions of PET to understanding

  13. Sea otter health: Challenging a pet hypothesis

    Directory of Open Access Journals (Sweden)

    Kevin D. Lafferty

    2015-12-01

    Full Text Available A recent series of studies on tagged sea otters (Enhydra lutris nereis challenges the hypothesis that sea otters are sentinels of a dirty ocean, in particular, that pet cats are the main source of exposure to Toxoplasma gondii in central California. Counter to expectations, sea otters from unpopulated stretches of coastline are less healthy and more exposed to parasites than city-associated otters. Ironically, now it seems that spillover from wildlife, not pets, dominates spatial patterns of disease transmission.

  14. Radiopharmaceuticals in PET, Progress and Promise

    Science.gov (United States)

    Wolf, A. P.; Fowler, J. S.

    1988-11-01

    It is the intention of this presentation to focus on the current state of radiopharmaceuticals for PET and where this is leading us. PET radiopharmaceuticals can be broken down into perhaps seven categories at present with each being applicable to a different aspect of human biochemistry. These are: metabolic probes, neurochemical probes, enzyme probes, ion channel blockers, blood flow agents, ethical drugs and other positron emitters.

  15. PET tracer for imaging of neuroendocrine tumors

    DEFF Research Database (Denmark)

    2013-01-01

    There is provided a radiolabelled peptide-based compound for diagnostic imaging using positron emission tomography (PET). The compound may thus be used for diagnosis of malignant diseases. The compound is particularly useful for imaging of somatostatin overexpression in tumors, wherein the compound...... is capable of being imaged by PET when administered with a target dose in the range of 150-350 MBq, such as 150-250 MBq, preferable in the range of 191-210 MBq....

  16. Sterilization influence on PET track membrane properties

    OpenAIRE

    Filippova, Ekaterina Olegovna; Pichugin, Vladimir Fyodorovich; Gradoboev, Aleksandr Vasilyevich; Filippov, Andrey Vladimirovich

    2016-01-01

    Polyethylene terephthalate (PET) track membrane (TM) has a great opportunity to use as a bio implant in ophthalmology's surgery due to its physical and chemical properties and biological comparability. Sterilization of medical implants can change its properties and can influence on regeneration process and success of surgical treatment. We researched influence on the PET track membrane of two sterilization methods wide used in medicine. The first sterilization method was steam sterilization. ...

  17. Sea otter health: Challenging a pet hypothesis.

    Science.gov (United States)

    Lafferty, Kevin D

    2015-12-01

    A recent series of studies on tagged sea otters (Enhydra lutris nereis) challenges the hypothesis that sea otters are sentinels of a dirty ocean, in particular, that pet cats are the main source of exposure to Toxoplasma gondii in central California. Counter to expectations, sea otters from unpopulated stretches of coastline are less healthy and more exposed to parasites than city-associated otters. Ironically, now it seems that spillover from wildlife, not pets, dominates spatial patterns of disease transmission.

  18. Digital PET compliance to EARL accreditation specifications.

    Science.gov (United States)

    Koopman, Daniëlle; Groot Koerkamp, Maureen; Jager, Pieter L; Arkies, Hester; Knollema, Siert; Slump, Cornelis H; Sanches, Pedro G; van Dalen, Jorn A

    2017-12-01

    Our aim was to evaluate if a recently introduced TOF PET system with digital photon counting technology (Philips Healthcare), potentially providing an improved image quality over analogue systems, can fulfil EANM research Ltd (EARL) accreditation specifications for tumour imaging with FDG-PET/CT. We have performed a phantom study on a digital TOF PET system using a NEMA NU2-2001 image quality phantom with six fillable spheres. Phantom preparation and PET/CT acquisition were performed according to the European Association of Nuclear Medicine (EANM) guidelines. We made list-mode ordered-subsets expectation maximization (OSEM) TOF PET reconstructions, with default settings, three voxel sizes (4 × 4 × 4 mm(3), 2 × 2 × 2 mm(3) and 1 × 1 × 1 mm(3)) and with/without point spread function (PSF) modelling. On each PET dataset, mean and maximum activity concentration recovery coefficients (RCmean and RCmax) were calculated for all phantom spheres and compared to EARL accreditation specifications. The RCs of the 4 × 4 × 4 mm(3) voxel dataset without PSF modelling proved closest to EARL specifications. Next, we added a Gaussian post-smoothing filter with varying kernel widths of 1-7 mm. EARL specifications were fulfilled when using kernel widths of 2 to 4 mm. TOF PET using digital photon counting technology fulfils EARL accreditation specifications for FDG-PET/CT tumour imaging when using an OSEM reconstruction with 4 × 4 × 4 mm(3) voxels, no PSF modelling and including a Gaussian post-smoothing filter of 2 to 4 mm.

  19. Clinical evaluation of PET image quality as a function of acquisition time in a new TOF-PET/MR compared to TOF-PET/CT - initial results

    Energy Technology Data Exchange (ETDEWEB)

    Zeimpekis, Konstantinos; Huellner, Martin; De Galiza Barbosa, Felipe; Ter Voert, Edwin; Davison, Helen; Delso, Gaspar; Veit-Haibach, Patrick [Nuclear Medicine, University Hospital Zurich (Switzerland)

    2015-05-18

    The recently available integrated PET/MR imaging can offer significant additional advances in clinical imaging. The purpose of this study was to compare the PET performance between a PET/CT scanner and an integrated TOF-PET/MR scanner concerning image quality parameters and quantification in terms of SUV as a function of acquisition time (a surrogate of dose). Five brain and five whole body patients were included in the study. The PET/CT scan was used as a reference and the PET/MR acquisition time was consecutively adjusted, taking into account the decay between the scans in order to expose both systems to the same amount of emitted signal. The acquisition times were then retrospectively reduced to assess the performance of the PET/MRI for lower count rates. Image quality, image sharpness, artifacts and noise were evaluated. SUV measurements were taken in the liver and in white matter to compare quantification. Quantitative evaluation showed good correlation between PET/CT and PET/MR brain SUVs. Liver correlation was lower, with uptake underestimation in PET/MR, partially justified by bio-redistribution. The clinical evaluation showed that PET/MR offers higher image quality and sharpness with lower levels of noise and artefacts compared to PET/CT with reduced acquisition times for whole body scans, while for brain scans there is no significant difference. The PET-component of the TOF-PET/MR showed higher image quality compared to PET/CT as tested with reduced imaging times. However, these results account mainly for body imaging, while no significant difference were found in brain imaging. This overall higher image quality suggests that the acquisition time or injected activity can be reduced by at least 37% on the PET/MR scanner.

  20. Reproducibility of 18F-FDG PET uptake measurements in head and neck squamous cell carcinoma on both PET/CT and PET/MR

    Science.gov (United States)

    Fischer, B M; Aznar, M C; Hansen, A E; Vogelius, I R; Löfgren, J; Andersen, F L; Loft, A; Kjaer, A; Højgaard, L; Specht, L

    2015-01-01

    Objective: To investigate reproducibility of fluorine-18 fludeoxyglucose (18F-FDG) uptake on 18F-FDG positron emission tomography (PET)/CT and 18F-FDG PET/MR scans in patients with head and neck squamous cell carcinoma (HNSCC). Methods: 30 patients with HNSCC were included in this prospective study. The patients were scanned twice before radiotherapy treatment with both PET/CT and PET/MR. Patients were scanned on the same scanners, 3 days apart and according to the same protocol. Metabolic tumour activity was measured by the maximum and peak standardized uptake value (SUVmax and SUVpeak, respectively), and total lesion glycolysis from the metabolic tumour volume defined from ≥50% SUVmax. Bland–Altman analysis with limits of agreement, coefficient of variation (CV) from the two modalities were performed in order to test the reproducibility. Furthermore, CVs from SUVmax and SUVpeak were compared. The area under the curve from cumulative SUV–volume histograms were measured and tested for reproducibility of the distribution of 18F-FDG uptake. Results: 24 patients had two pre-treatment PET/CT scans and 21 patients had two pre-treatment PET/MR scans available for further analyses. Mean difference for SUVmax, peak and mean was approximately 4% for PET/CT and 3% for PET/MR, with 95% limits of agreement less than ±20%. CV was small (5–7%) for both modalities. There was no significant difference in CVs between PET/CT and PET/MR (p = 0.31). SUVmax was not more reproducible than SUVpeak (p = 0.09). Conclusion: 18F-FDG uptake in PET/CT and PET/MR is highly reproducible and we found no difference in reproducibility between PET/CT and PET/MR. Advances in knowledge: This is the first report to test reproducibility of PET/CT and PET/MR. PMID:25634069

  1. PeneloPET, a Monte Carlo PET simulation tool based on PENELOPE: features and validation

    Energy Technology Data Exchange (ETDEWEB)

    Espana, S; Herraiz, J L; Vicente, E; Udias, J M [Grupo de Fisica Nuclear, Departmento de Fisica Atomica, Molecular y Nuclear, Universidad Complutense de Madrid, Madrid (Spain); Vaquero, J J; Desco, M [Unidad de Medicina y CirugIa Experimental, Hospital General Universitario Gregorio Maranon, Madrid (Spain)], E-mail: jose@nuc2.fis.ucm.es

    2009-03-21

    Monte Carlo simulations play an important role in positron emission tomography (PET) imaging, as an essential tool for the research and development of new scanners and for advanced image reconstruction. PeneloPET, a PET-dedicated Monte Carlo tool, is presented and validated in this work. PeneloPET is based on PENELOPE, a Monte Carlo code for the simulation of the transport in matter of electrons, positrons and photons, with energies from a few hundred eV to 1 GeV. PENELOPE is robust, fast and very accurate, but it may be unfriendly to people not acquainted with the FORTRAN programming language. PeneloPET is an easy-to-use application which allows comprehensive simulations of PET systems within PENELOPE. Complex and realistic simulations can be set by modifying a few simple input text files. Different levels of output data are available for analysis, from sinogram and lines-of-response (LORs) histogramming to fully detailed list mode. These data can be further exploited with the preferred programming language, including ROOT. PeneloPET simulates PET systems based on crystal array blocks coupled to photodetectors and allows the user to define radioactive sources, detectors, shielding and other parts of the scanner. The acquisition chain is simulated in high level detail; for instance, the electronic processing can include pile-up rejection mechanisms and time stamping of events, if desired. This paper describes PeneloPET and shows the results of extensive validations and comparisons of simulations against real measurements from commercial acquisition systems. PeneloPET is being extensively employed to improve the image quality of commercial PET systems and for the development of new ones.

  2. Factors in children's attitudes toward pets.

    Science.gov (United States)

    Kidd, A H; Kidd, R M

    1990-06-01

    This study investigates parental attitudes, family size, and structure, and presence or absence of household pets as influences on children's attitudes toward pets. 700 parents completed a Melson Parent Questionnaire which assesses children's activities with, interest in, and responsibility for pets, and completed either the Wilson Attitude Inventory for Pet Owners or for Nonpet Owners. Results indicated: that children of strongly attached adults and in pet-owning homes scored higher on Activities and Interest than children of weakly attached adults and in nonpet-owning homes; that children of both sexes in one-parent homes scored higher on Responsibility than in two-parent homes; that boys scored higher on Interest, girls on Activities, and both sexes on Responsibility when mothers worked full time rather than part-time; that girls scored higher on Interest and, in pet-owning homes, on Responsibility than boys; that preschoolers scored lower on Activities and Interest than older children, and that grade schoolers scored higher on Responsibility than preschoolers or high schoolers.

  3. Can body volume be determined by PET?

    Energy Technology Data Exchange (ETDEWEB)

    Hentschel, Michael; Paul, Dominik; Mix, Michael; Moser, Ernst; Brink, Ingo [University Hospital Freiburg, Division of Nuclear Medicine, Section of Positron Emission Tomography, Freiburg (Germany); Korsten-Reck, Ulrike [University Hospital Freiburg, Division of Sports Medicine, Freiburg (Germany); Mueller, Frank [PET-Institute Rhein-Neckar, Ludwigshafen (Germany); Merk, Stefan [Kantonsspital Basel, Division of Nuclear Medicine, Basel (Switzerland)

    2005-04-01

    To avoid dependence on body weight, the standardised uptake value (SUV) in positron emission tomography (PET) can instead be normalised to the lean body mass (LBM), which can be determined from body volume and mass. This study was designed to answer the following questions: Firstly, can the total body volume in principle be determined using PET? Secondly, is the precision of this measurement comparable to that achieved using an established standard method. Ten patients were examined during oncological whole-body PET examinations. The whole-body volume of the patients was determined from the transmission scan in PET. Air displacement plethysmography with BOD POD was used for comparison as the standard method of volume determination. In all patients, the whole-body volumes could be determined using PET and the standard method. Bland and Altman [23] analysis for agreement between the volumes determined by the two methods (presentation of differences vs means) revealed a very small difference of -0.14 l. With a mean patient volume of 71.81{+-}15.93 l, the relative systematic error is only <0.1%. On this basis, equality of the volume values determined by the two methods can be assumed. PET can be used as a supplementary method for experimental determination of whole-body volume and total body fat in tumour patients. The fat content can be used to calculate the LBM and to determine body weight-independent SUVs (SUV{sub LBM}). (orig.)

  4. Nutritional Sustainability of Pet Foods12

    Science.gov (United States)

    Swanson, Kelly S.; Carter, Rebecca A.; Yount, Tracy P.; Aretz, Jan; Buff, Preston R.

    2013-01-01

    Sustainable practices meet the needs of the present without compromising the ability of future generations to meet their needs. Applying these concepts to food and feed production, nutritional sustainability is the ability of a food system to provide sufficient energy and essential nutrients required to maintain good health in a population without compromising the ability of future generations to meet their nutritional needs. Ecological, social, and economic aspects must be balanced to support the sustainability of the overall food system. The nutritional sustainability of a food system can be influenced by several factors, including the ingredient selection, nutrient composition, digestibility, and consumption rates of a diet. Carbon and water footprints vary greatly among plant- and animal-based ingredients, production strategy, and geographical location. Because the pet food industry is based largely on by-products and is tightly interlinked with livestock production and the human food system, however, it is quite unique with regard to sustainability. Often based on consumer demand rather than nutritional requirements, many commercial pet foods are formulated to provide nutrients in excess of current minimum recommendations, use ingredients that compete directly with the human food system, or are overconsumed by pets, resulting in food wastage and obesity. Pet food professionals have the opportunity to address these challenges and influence the sustainability of pet ownership through product design, manufacturing processes, public education, and policy change. A coordinated effort across the industry that includes ingredient buyers, formulators, and nutritionists may result in a more sustainable pet food system. PMID:23493530

  5. Effect of PET functionalization in composites of

    Directory of Open Access Journals (Sweden)

    Cristina Cazan

    2017-03-01

    Full Text Available The functionalization of polyethylene terephthalate (PET from tire rubber–PET–high density polyethylene (HDPE composites represents a key strategy for improving the composite properties. This is a practical and effective method to improve the interface between matrix (waste tire rubber and fillers (waste PET and HDPE. By PET functionalization, adherence and surface properties of composite materials can be controlled. PET functionalization was performed with polyethylene glycol (PEG 400, 1% and sodium dodecyl sulphate (SDS 1%. The characterization of the components and composite are discussed in terms of surface energy values (evaluated from water contact angle measurements and surface morphology by using scanning electron microscopy (SEM. The structural and conformational changes were investigated by Fourier Transform Infrared (FTIR Spectroscopy while the crystalline structure was studied by X-ray diffraction (XRD. The improved interfacial adhesion, thermal stability and mechanical properties (stress–strain, compression and impact resistance of the composites are correlated with the PET functionalization, with non-ionic (PEG and an anionic surfactant (SDS. The results proved that the interface properties are improved by functionalization of PET. The best mechanical properties were recorded at 30 min moulding. The samples with 45% PET–SDS showed the best combination of mechanical properties: tensile strength (1.56 N/mm2, impact strength (43.72 kJ/m2 and compression (158.78 N/mm2.

  6. Efeito da aplicação de etileno na qualidade pós-colheita de frutos de pimentão vermelhos e amarelos Effect of the application of ethylene on the postharvest quality of red and yellow bell peppers fruits

    Directory of Open Access Journals (Sweden)

    2007-12-01

    Full Text Available O extenso período para a maturação do pimentão faz com que a colheita antecipada seja alvo de interesse por parte dos produtores. Entretanto, para a comercialização é necessário que os frutos apresentem no mínimo 70% da sua coloração. Uma forma de promover o aparecimento da cor seria submeter os frutos à ação de etileno. Neste trabalho estudou-se a aplicação do gás etileno na pós-colheita de frutos de pimentão 'Rubia R' (frutos vermelhos e 'Prador R' (frutos amarelos, que foram coletados quando apresentavam 15% de sua superfície colorida. O gás (120 µL L-1 foi aplicado a cada 6 horas durante 88 horas, em câmara mantida a 22ºC e 80% de UR, onde os frutos estavam dispostos em prateleiras. O etileno acelerou o aparecimento da cor e promoveu aumento no teor de sólidos solúveis nos pimentões 'Rubia R'. Os valores de ácido ascórbico, acidez titulável e pH dos frutos não sofreram alterações com a aplicação do gás para ambas as cultivares.The long period for bell pepper fruit maturation makes early harvests object of interest for farmers. However, pepper fruits must have at least 70% of their coloration for commercialization. The exposure of fruits to ethylene gas can enhance uniform color. This work had the objective to study the ethylene action on postharvest behavior of bell peppers 'Prador R' (yellow fruits and 'Rubia R' (red fruits picked with 15% of their surface colored. The gas (120 µL L-1 was applied each six hours during 88 hours in a chamber maintained at 22ÚC and 80% RH on fruits kept in shelves. The ethylene accelerated the color development and increased the soluble solids content of bell peppers 'Rubia R'. The ascorbic acid, titratable acidity and pH of fruits were not affected due to gas application for both pepper varieties.

  7. Imaging with {sup 124}I in differentiated thyroid carcinoma: is PET/MRI superior to PET/CT?

    Energy Technology Data Exchange (ETDEWEB)

    Binse, I.; Poeppel, T.D.; Ruhlmann, M.; Gomez, B.; Bockisch, A.; Rosenbaum-Krumme, S.J. [University of Duisburg-Essen, Medical Faculty, Department of Nuclear Medicine, Essen (Germany); Umutlu, L. [University of Duisburg-Essen, Medical Faculty, Department of Radiology, Essen (Germany)

    2016-06-15

    The aim of this study was to compare integrated PET/CT and PET/MRI for their usefulness in detecting and categorizing cervical iodine-positive lesions in patients with differentiated thyroid cancer using {sup 124}I as tracer. The study group comprised 65 patients at high risk of iodine-positive metastasis who underwent PET/CT (low-dose CT scan, PET acquisition time 2 min; PET/CT{sub 2}) followed by PET/MRI of the neck 24 h after {sup 124}I administration. PET images from both modalities were analysed for the numbers of tracer-positive lesions. Two different acquisition times were used for the comparisons, one matching the PET/CT{sub 2} acquisition time (2 min, PET/MRI{sub 2}) and the other covering the whole MRI scan time (30 min, PET/MRI{sub 30}). Iodine-positive lesions were categorized as metastasis, thyroid remnant or inconclusive according to their location on the PET/CT images. Morphological information provided by MRI was considered for evaluation of lesions on PET/MRI and for volume information. PET/MRI{sub 2} detected significantly more iodine-positive metastases and thyroid remnants than PET/CT{sub 2} (72 vs. 60, p = 0.002, and 100 vs. 80, p = 0.001, respectively), but the numbers of patients with at least one tumour lesion identified were not significantly different (21/65 vs. 17/65 patients). PET/MRI{sub 30} tended to detect more PET-positive metastases than PET/MRI{sub 2} (88 vs. 72), but the difference was not significant (p = 0.07). Of 21 lesions classified as inconclusive on PET/CT, 5 were assigned to metastasis or thyroid remnant when evaluated by PET/MRI. Volume information was available in 34 % of iodine-positive metastases and 2 % of thyroid remnants on PET/MRI. PET/MRI of the neck was found to be superior to PET/CT in detecting iodine-positive lesions. This was attributed to the higher sensitivity of the PET component, Although helpful in some cases, we found no substantial advantage of PET/MRI over PET/CT in categorizing iodine

  8. Avaliação do uso de poli(tereftalato de etileno (PET como matriz de imobilização de cinzas de incineradores Assessment of the use of polyethylene terephthalate (PET as matrix for immobilization of incinerator ash

    Directory of Open Access Journals (Sweden)

    Flávia Gonçalves Pacheco

    2009-01-01

    Full Text Available Industrial hazardous wastes must receive appropriate treatment to ensure a safe disposal to humans and environment. One of the techniques adopted for this purpose is the stabilization/solidification in polymer matrices. This paper evaluated the use of recycled polyethylene terephthalate as an incorporation matrix of incinerator ash. The polymer and the ash were submitted to an extrusion process in different percentages. The final product was evaluated through thermal and leaching tests and the leachate extracts constituents were determinated by atomic absorption spectrophotometry. The results showed a reduction in the release of substances up to 99% by mass for the conditions used.

  9. Guidelines for 18F-FDG PET and PET-CT imaging in paediatric oncology

    DEFF Research Database (Denmark)

    Stauss, J.; Franzius, C.; Pfluger, T.

    2008-01-01

    tomography ((18)F-FDG PET) in paediatric oncology. The Oncology Committee of the European Association of Nuclear Medicine (EANM) has published excellent procedure guidelines on tumour imaging with (18)F-FDG PET (Bombardieri et al., Eur J Nucl Med Mol Imaging 30:BP115-24, 2003). These guidelines, published...

  10. Imaging corn plants with PhytoPET, a modular PET system for plant biology

    Energy Technology Data Exchange (ETDEWEB)

    Lee, S.; Kross, B.; McKisson, J.; McKisson, J. E.; Weisenberger, A. G.; Xi, W.; Zorn, C.; Bonito, G.; Howell, C. R.; Reid, C. D.; Crowell, A.; Cumberbatch, L. C.; Topp, C.; Smith, M. F.

    2013-11-01

    PhytoPET is a modular positron emission tomography (PET) system designed specifically for plant imaging. The PhytoPET design allows flexible arrangements of PET detectors based on individual standalone detector modules built from single Hamamatsu H8500 position sensitive photomultiplier tubes and pixelated LYSO arrays. We have used the PhytoPET system to perform preliminary corn plant imaging studies at the Duke University Biology Department Phytotron. Initial evaluation of the PhytoPET system to image the biodistribution of the positron emitting tracer {sup 11}C in corn plants is presented. {sup 11}CO{sub 2} is loaded into corn seedlings by a leaf-labeling cuvette and translocation of {sup 11}C-sugars is imaged by a flexible arrangement of PhytoPET modules on each side. The PhytoPET system successfully images {sup 11}C within corn plants and allows for the dynamic measurement of {sup 11}C-sugar translocation from the leaf to the roots.

  11. Development of Filtering Methods for PET Signals Contaminated by RF Pulses for Combined PET-MRI

    Science.gov (United States)

    Huh, Yoonsuk; Choi, Yong; Hong, Key Jo; Hu, Wei; Kang, Jihoon; Jung, Jin Ho; Song, Myung Sung; Park, Hyun-wook; Kim, Byung-Tae

    2013-10-01

    This paper presents the development of filtering methods for positron emission tomography (PET) signals contaminated by radio frequency (RF) pulses for combined PET and clinical 3-T magnetic resonance imaging (MRI). The filtering methods include software, hardware, and hybrid correction methods. In the software correction method, PET signals are assessed, and valid signals are identified based on the characteristics of a typical PET signal using Field-Programmable Gate Array (FPGA)-based programming. The hardware correction method makes use of differential-to-single-ended and low-pass filter circuits for PET analog signals. The hybrid correction method involves the sequential application of both the hardware and software methods. Both valid and contaminated PET signals are measured with an oscilloscope. An evaluation is then made of the performance (energy resolution, photopeak channel, total counts, and coincidence timing resolution) of the PET detector modules with and without various MR sequences (gradient echo, spin echo T1 sequence). For all correction methods, the energy resolution, photopeak position, and coincidence timing resolution with MR sequences are similar (noise signals and reduce count loss while preserving the valid analog signals of MR sequences, is reliable and useful for the development of simultaneous PET-MRI.

  12. Assess PET/MR in diagnosis of disease in comparison with PET/CT

    Energy Technology Data Exchange (ETDEWEB)

    Yan, Jianhua; Lim, Jason Chu-Chern; Loi, Hoi Yin; Totoman, John [A*STAR-NUS Clinical Imaging Research Centre (Singapore); Sinha, Arvind Kumar; Quek, Swee Titan [Department of Diagnostic Imaging, National University Hospital (Singapore); Townsend, David [A*STAR-NUS Clinical Imaging Research Centre (Singapore)

    2015-05-18

    The aim of this study is to assess the performance of 18F-FDG whole body PET/MRI in comparison with PET/CT based on SUV. Anatomical location of lesion with Dixon MRI and additional value of advanced MRI technology such as diffusion weighted MR imaging in diagnosis of malignant disease will also be investigated.

  13. PET motion correction in context of integrated PET/MR: Current techniques, limitations, and future projections.

    Science.gov (United States)

    Gillman, Ashley; Smith, Jye; Thomas, Paul; Rose, Stephen; Dowson, Nicholas

    2017-12-01

    Patient motion is an important consideration in modern PET image reconstruction. Advances in PET technology mean motion has an increasingly important influence on resulting image quality. Motion-induced artifacts can have adverse effects on clinical outcomes, including missed diagnoses and oversized radiotherapy treatment volumes. This review aims to summarize the wide variety of motion correction techniques available in PET and combined PET/CT and PET/MR, with a focus on the latter. A general framework for the motion correction of PET images is presented, consisting of acquisition, modeling, and correction stages. Methods for measuring, modeling, and correcting motion and associated artifacts, both in literature and commercially available, are presented, and their relative merits are contrasted. Identified limitations of current methods include modeling of aperiodic and/or unpredictable motion, attaining adequate temporal resolution for motion correction in dynamic kinetic modeling acquisitions, and maintaining availability of the MR in PET/MR scans for diagnostic acquisitions. Finally, avenues for future investigation are discussed, with a focus on improvements that could improve PET image quality, and that are practical in the clinical environment. © 2017 American Association of Physicists in Medicine.

  14. An update on the role of PET/CT and PET/MRI in ovarian cancer

    Energy Technology Data Exchange (ETDEWEB)

    Khiewvan, Benjapa [Hospital of the University of Pennsylvania, Department of Radiology, Philadelphia, PA (United States); Mahidol University, Division of Nuclear Medicine, Department of Radiology, Faculty of Medicine Siriraj Hospital, Bangkok (Thailand); Torigian, Drew A.; Emamzadehfard, Sahra; Paydary, Koosha; Salavati, Ali; Houshmand, Sina; Werner, Thomas J.; Alavi, Abass [Hospital of the University of Pennsylvania, Department of Radiology, Philadelphia, PA (United States)

    2017-06-15

    This review article summarizes the role of PET/CT and PET/MRI in ovarian cancer. With regard to the diagnosis of ovarian cancer, the presence of FDG uptake within the ovary of a postmenopausal woman raises the concern for ovarian cancer. Multiple studies show that FDG PET/CT can detect lymph node and distant metastasis in ovarian cancer with high accuracy and may, therefore, alter the management to obtain better clinical outcomes. Although PET/CT staging is superior for N and M staging of ovarian cancer, its role is limited for T staging. Additionally, FDG PET/CT is of great benefit in evaluating treatment response and has prognostic value in patients with ovarian cancer. FDG PET/CT also has value to detect recurrent disease, particularly in patients with elevated serum CA-125 levels and negative or inconclusive conventional imaging test results. PET/MRI may beneficial for tumor staging because MRI has higher soft tissue contrast and no ionizing radiation exposure compared to CT. Some non-FDG PET radiotracers such as {sup 18}F-fluorothymidine (FLT) or {sup 11}C-methionine (MET) have been studied in preclinical and clinical studies as well and may play a role in the evaluation of patients with ovarian cancer. (orig.)

  15. Indikationer for anvendelse af PET eller PET/CT hos patienter med brystkræft

    DEFF Research Database (Denmark)

    Bernsdorf, Mogens; Graff, Jesper

    2011-01-01

    PET and PET/CT, using 18F-fluoro-2-deoxy-D-glucose, are not suited for primary diagnostics of small tumours or lymph node metastases to the axilla. In return, the method has a high sensitivity and specificity regarding the detection of loco-regional recurrence and metastases to mediastinal lymph...

  16. Clinical Evaluation of PET Image Quality as a Function of Acquisition Time in a New TOF-PET/MRI Compared to TOF-PET/CT--Initial Results.

    Science.gov (United States)

    Zeimpekis, Konstantinos G; Barbosa, Felipe; Hüllner, Martin; ter Voert, Edwin; Davison, Helen; Veit-Haibach, Patrick; Delso, Gaspar

    2015-10-01

    The purpose of this study was to compare only the performance of the PET component between a TOF-PET/CT (henceforth noted as PET/CT) scanner and an integrated TOF-PET/MRI (henceforth noted as PET/MRI) scanner concerning image quality parameters and quantification in terms of standardized uptake value (SUV) as a function of acquisition time (a surrogate of dose). The CT and MR image quality were not assessed, and that is beyond the scope of this study. Five brain and five whole-body patients were included in the study. The PET/CT scan was used as a reference and the PET/MRI acquisition time was consecutively adjusted, taking into account the decay between the scans in order to expose both systems to the same amount of the emitted signal. The acquisition times were then retrospectively reduced to assess the performance of the PET/MRI for lower count rates. Image quality, image sharpness, artifacts, and noise were evaluated. SUV measurements were taken in the liver and in the white matter to compare quantification. Quantitative evaluation showed strong correlation between PET/CT and PET/MRI brain SUVs. Liver correlation was good, however, with lower uptake estimation in PET/MRI, partially justified by bio-redistribution. The clinical evaluation showed that PET/MRI offers higher image quality and sharpness with lower levels of noise and artifacts compared to PET/CT with reduced acquisition times for whole-body scans while for brain scans there is no significant difference. The TOF-PET/MRI showed higher image quality compared to TOF-PET/CT as tested with reduced imaging times. However, this result accounts mainly for body imaging, while no significant differences were found in brain imaging.

  17. Bacteriophages safely reduce Salmonella contamination in pet food and raw pet food ingredients

    Science.gov (United States)

    Soffer, Nitzan; Abuladze, Tamar; Woolston, Joelle; Li, Manrong; Hanna, Leigh Farris; Heyse, Serena; Charbonneau, Duane; Sulakvelidze, Alexander

    2016-01-01

    ABSTRACT Contamination of pet food with Salmonella is a serious public health concern, and several disease outbreaks have recently occurred due to human exposure to Salmonella tainted pet food. The problem is especially challenging for raw pet foods (which include raw meats, seafood, fruits, and vegetables). These foods are becoming increasingly popular because of their nutritional qualities, but they are also more difficult to maintain Salmonella-free because they lack heat-treatment. Among various methods examined to improve the safety of pet foods (including raw pet food), one intriguing approach is to use bacteriophages to specifically kill Salmonella serotypes. At least 2 phage preparations (SalmoFresh® and Salmonelex™) targeting Salmonella are already FDA cleared for commercial applications to improve the safety of human foods. However, similar preparations are not yet available for pet food applications. Here, we report the results of evaluating one such preparation (SalmoLyse®) in reducing Salmonella levels in various raw pet food ingredients (chicken, tuna, turkey, cantaloupe, and lettuce). Application of SalmoLyse® in low (ca. 2–4×106 PFU/g) and standard (ca. 9×106 PFU/g) concentrations significantly (P Salmonella contamination in all raw foods examined compared to control treatments. When SalmoLyse®-treated (ca. 2×107 PFU/g) dry pet food was fed to cats and dogs, it did not trigger any deleterious side effects in the pets. Our data suggest that the bacteriophage cocktail lytic for Salmonella can significantly and safely reduce Salmonella contamination in various raw pet food ingredients. PMID:27738557

  18. Bacteriophages safely reduce Salmonella contamination in pet food and raw pet food ingredients.

    Science.gov (United States)

    Soffer, Nitzan; Abuladze, Tamar; Woolston, Joelle; Li, Manrong; Hanna, Leigh Farris; Heyse, Serena; Charbonneau, Duane; Sulakvelidze, Alexander

    2016-01-01

    Contamination of pet food with Salmonella is a serious public health concern, and several disease outbreaks have recently occurred due to human exposure to Salmonella tainted pet food. The problem is especially challenging for raw pet foods (which include raw meats, seafood, fruits, and vegetables). These foods are becoming increasingly popular because of their nutritional qualities, but they are also more difficult to maintain Salmonella-free because they lack heat-treatment. Among various methods examined to improve the safety of pet foods (including raw pet food), one intriguing approach is to use bacteriophages to specifically kill Salmonella serotypes. At least 2 phage preparations (SalmoFresh® and Salmonelex™) targeting Salmonella are already FDA cleared for commercial applications to improve the safety of human foods. However, similar preparations are not yet available for pet food applications. Here, we report the results of evaluating one such preparation (SalmoLyse®) in reducing Salmonella levels in various raw pet food ingredients (chicken, tuna, turkey, cantaloupe, and lettuce). Application of SalmoLyse® in low (ca. 2-4×106 PFU/g) and standard (ca. 9×106 PFU/g) concentrations significantly (P contamination in all raw foods examined compared to control treatments. When SalmoLyse®-treated (ca. 2×107 PFU/g) dry pet food was fed to cats and dogs, it did not trigger any deleterious side effects in the pets. Our data suggest that the bacteriophage cocktail lytic for Salmonella can significantly and safely reduce Salmonella contamination in various raw pet food ingredients.

  19. PET/MR in children. Initial clinical experience in paediatric oncology using an integrated PET/MR scanner

    OpenAIRE

    Hirsch, Franz Wolfgang; Sattler, Bernhard; Sorge, Ina; Kurch, Lars; Viehweger, Adrian; Ritter, Lutz; WERNER, Peter; Jochimsen, Thies; Barthel, Henryk; Bierbach, Uta; Till, Holger; Sabri, Osama; Kluge, Regine

    2013-01-01

    Use of PET/MR in children has not previously been reported, to the best of our knowledge. Children with systemic malignancies may benefit from the reduced radiation exposure offered by PET/MR. We report our initial experience with PET/MR hybrid imaging and our current established sequence protocol after 21 PET/MR studies in 15 children with multifocal malignant diseases. The effective dose of a PET/MR scan was only about 20% that of the equivalent PET/CT examination. Simultaneous acquisition ...

  20. Controle da maturação e conservação da qualidade pós-colheita de caqui 'Fuyu' pelo manejo do etileno Postharvest control of ripening and quality maintenance of 'Fuyu' persimmon fruit by ethylene handling

    Directory of Open Access Journals (Sweden)

    Juliana Golin Krammes

    2005-12-01

    Full Text Available O presente estudo avaliou o impacto do tratamento 1-MCP sobre a conservação da qualidade de caqui 'Fuyu', e como a exposição pós-colheita ao etileno pode afetar a eficácia do 1-MCP. Os frutos foram colhidos em quatro diferentes estádios de maturação conforme indicado pelo índice de coloração da casca, após a maturação fisiológica. Frutos foram tratados com 0,1 e 1 µL ·L-1 de 1-MCP, um dia após a colheita, e mantidos a 23ºC por até 45 dias, em ar ambiente contendo baixa (d" 0,1 µL ·L-1 ou alta (3 ± 2 µL ·L-1 concentração de etileno. O tratamento com 1-MCP retardou o amolecimento da polpa, o desenvolvimento da coloração dos frutos e o aumento da produção de etileno, mas não alterou o teor de açúcares solúveis e a acidez titulável. A vida pós-colheita (período entre a colheita e o amolecimento da polpa dos frutos foi aumentada por até 20 dias em relação aos frutos não-tratados. Frutos colhidos em estádio avançado de maturação apresentaram menor vida pós-colheita, independentemente do tratamento 1-MCP. O benefício do tratamento 1-MCP foi maior para frutos colhidos precocemente e para frutos expostos a 3 µL ·L-1 de etileno.The present study determined the impact of 1-mcp treatment on the quality maintenance of 'Fuyu' persimmons, and how the postharvest exposure to ethylene could influence the 1-MCP effectiveness. The fruits were harvested at four different ripening stages according to skin color, after physiologic maturity. Fruits were treated with 0.1 and 1.0 µL ·L-1 of 1-MCP one day after harvest, and then held at 23ºC for up to 45 days in air with low (d" 0,1 µL ·L-1 or high (3 ± 2 µL ·L-1 ethylene . 1-MCP treatment delayed fruit softening and changes of skin color and the increase in the ethylene production, whereas it had no effect on soluble solids content and on titratable acidity. The postharvest life (period between harvest and pulp softening of fruits was increased for up to 20 days

  1. Avaliação da biocompatibilidade de implantes mamários de silicone esterilizados por calor seco e pelo óxido de etileno Biocompatibility assessment of silicone gel breast implants sterilized by dry-heat and by ethylene oxide

    Directory of Open Access Journals (Sweden)

    Janice Campos de Azevedo

    2006-06-01

    Full Text Available Os implantes mamários de silicone têm sido empregados, tanto nas cirurgias de aumento de mama, quanto na reconstrução do tecido mamário. A segurança biológica deste tipo de implante deve ser garantida, pois, em função da esterilização estes materiais, podem sofrer alterações oriundas dos processos esterilizantes por comprometimento da estrutura química dos polímeros. O objetivo deste trabalho consistiu na avaliação da biocompatibilidade de implantes mamários preenchidos com gel de silicone, de superfície lisa e texturizada submetidos à esterilização por calor seco e óxido de etileno. Empregou-se, para tanto, método in vitro, avaliando a citotoxicidade pelo método de captura do vermelho neutro, utilizando a linhagem celular NCTC clone 929. Os resultados obtidos demonstraram não haver comprometimento da biocompatibilidade dos biomateriais submetidos aos dois processos (calor seco e óxido de etileno, assim como comprovaram a eficácia de ambos na esterilização dos implantes.Silicone breast implants have been widely used for mammary augmentation and reconstruction surgery. Biological safety of these implants can be altered by sterilization methods. This study consisted of the biocompatibility assessment of smooth and textured silicone gel breast implants sterilized by dry-heat and ethylene oxide through cell viability, employing neutral red uptake method. The NCTC clone 929 cell were employed and the results showed no cytotoxicity of implants after both sterilization processes.

  2. Reproducibility of Quantitative Brain Imaging Using a PET-Only and a Combined PET/MR System.

    Science.gov (United States)

    Lassen, Martin L; Muzik, Otto; Beyer, Thomas; Hacker, Marcus; Ladefoged, Claes Nøhr; Cal-González, Jacobo; Wadsak, Wolfgang; Rausch, Ivo; Langer, Oliver; Bauer, Martin

    2017-01-01

    The purpose of this study was to test the feasibility of migrating a quantitative brain imaging protocol from a positron emission tomography (PET)-only system to an integrated PET/MR system. Potential differences in both absolute radiotracer concentration as well as in the derived kinetic parameters as a function of PET system choice have been investigated. Five healthy volunteers underwent dynamic (R)-[11C]verapamil imaging on the same day using a GE-Advance (PET-only) and a Siemens Biograph mMR system (PET/MR). PET-emission data were reconstructed using a transmission-based attenuation correction (AC) map (PET-only), whereas a standard MR-DIXON as well as a low-dose CT AC map was applied to PET/MR emission data. Kinetic modeling based on arterial blood sampling was performed using a 1-tissue-2-rate constant compartment model, yielding kinetic parameters (K1 and k2) and distribution volume (V T ). Differences for parametric values obtained in the PET-only and the PET/MR systems were analyzed using a 2-way Analysis of Variance (ANOVA). Comparison of DIXON-based AC (PET/MR) with emission data derived from the PET-only system revealed average inter-system differences of -33 ± 14% (p PET/MR resulted in slightly lower systematic differences of -16 ± 18% for K1 and -9 ± 10% for k2. The average differences in V T were -18 ± 10% (p PET/MR and PET-only imaging due to different standard AC methods employed. Therefore, a transfer of imaging protocols from PET-only to PET/MR systems is not straightforward without application of proper correction methods. Clinical Trial Registration: www.clinicaltrialsregister.eu, identifier 2013-001724-19.

  3. Reproducibility of Quantitative Brain Imaging Using a PET-Only and a Combined PET/MR System

    Science.gov (United States)

    Lassen, Martin L.; Muzik, Otto; Beyer, Thomas; Hacker, Marcus; Ladefoged, Claes Nøhr; Cal-González, Jacobo; Wadsak, Wolfgang; Rausch, Ivo; Langer, Oliver; Bauer, Martin

    2017-01-01

    The purpose of this study was to test the feasibility of migrating a quantitative brain imaging protocol from a positron emission tomography (PET)-only system to an integrated PET/MR system. Potential differences in both absolute radiotracer concentration as well as in the derived kinetic parameters as a function of PET system choice have been investigated. Five healthy volunteers underwent dynamic (R)-[11C]verapamil imaging on the same day using a GE-Advance (PET-only) and a Siemens Biograph mMR system (PET/MR). PET-emission data were reconstructed using a transmission-based attenuation correction (AC) map (PET-only), whereas a standard MR-DIXON as well as a low-dose CT AC map was applied to PET/MR emission data. Kinetic modeling based on arterial blood sampling was performed using a 1-tissue-2-rate constant compartment model, yielding kinetic parameters (K1 and k2) and distribution volume (VT). Differences for parametric values obtained in the PET-only and the PET/MR systems were analyzed using a 2-way Analysis of Variance (ANOVA). Comparison of DIXON-based AC (PET/MR) with emission data derived from the PET-only system revealed average inter-system differences of −33 ± 14% (p PET/MR resulted in slightly lower systematic differences of −16 ± 18% for K1 and −9 ± 10% for k2. The average differences in VT were −18 ± 10% (p PET/MR and PET-only imaging due to different standard AC methods employed. Therefore, a transfer of imaging protocols from PET-only to PET/MR systems is not straightforward without application of proper correction methods. Clinical Trial Registration: www.clinicaltrialsregister.eu, identifier 2013-001724-19 PMID:28769742

  4. PET application in psychiatry and psychopharmacology

    Energy Technology Data Exchange (ETDEWEB)

    Suhara, Tetsuya [National Inst. of Radiological Sciences, Chiba (Japan)

    1999-07-01

    In the last few decades diagnostic and research tools in the medical field have made great advances, yet psychiatry has lacked sufficiently sensitive tools to measure the aberration of brain functions. Recently however, the development of Positron emission tomography (PET) techniques has made it possible to measure changes in neurochemical components in mental disorders and the effect of psychoactive drugs in living human brain. Most of the advancement in the psychiatric field has came from the development psychoactive drugs. Brain research involving identification of neurotransmission is largely based on compounds developed in psychopharmacology. Some of these compounds have been radiolabelled and used as radioligands for quantitative examination of neuroreceptors and other aspects of neurotransmission. Using PET, radioligand binding can now be examined in the human brain in vivo. PET techniques also allow examination of an unlabelled drug by examination of its interaction with a radioligand. So one potential of PET in psychiatry is to investigate the mechanism of psychoactive drugs. Antidepressants modulate serotonin transmission by inhibiting serotonin reuptake from the synaptic cleft. High affinity [{sup 3}H]imipramine binding sites in mammalian brain have been labelled to investigate serotonin transporters in living human brain by PET. Cyanoimipramine which is described as a potent serotonin reuptake inhibitor, was labelled with {sup 11}C. In a PET experiment with 6 healthy human subjects, a high accumulation of [{sup 11}C]cyanoimipramine was found in the thalamus and striatum and lowest accumulation was observed in the cerebellum, a region relatively void of serotonin transporters. The thalamus to cerebellum ratio was about 2 at 90 min after the injection of the tracer. Recently, [{sup 11}C]McN5652-X has been introduced as a better tracer for serotonin transporter imaging. Employing [{sup 11}C]McN5652-X in a PET study of 7 healthy human subjects, a high

  5. Design Features and Mutual Compatibility Studies of the Time-of-Flight PET Capable GE SIGNA PET/MR System.

    Science.gov (United States)

    Levin, Craig S; Maramraju, Sri Harsha; Khalighi, Mohammad Mehdi; Deller, Timothy W; Delso, Gaspar; Jansen, Floris

    2016-08-01

    A recent entry into the rapidly evolving field of integrated PET/MR scanners is presented in this paper: a whole body hybrid PET/MR system (SIGNA PET/MR, GE Healthcare) capable of simultaneous acquisition of both time-of-flight (TOF) PET and high resolution MR data. The PET ring was integrated into an existing 3T MR system resulting in a (patient) bore opening of 60 cm diameter, with a 25 cm axial FOV. PET performance was evaluated both on the standalone PET ring and on the same detector integrated into the MR system, to assess the level of mutual interference between both subsystems. In both configurations we obtained detector performance data. PET detector performance was not significantly affected by integration into the MR system. The global energy resolution was within 2% (10.3% versus 10.5%), and the system coincidence time resolution showed a maximum change of < 3% (385 ps versus 394 ps) when measured outside MR and during simultaneous PET/MRI acquisitions, respectively. To evaluate PET image quality and resolution, the NEMA IQ phantom was acquired with MR idle and with MR active. Impact of PET on MR IQ was assessed by comparing SNR with PET acquisition on and off. B0 and B1 homogeneities were acquired before and after the integration of the PET ring inside the magnet. In vivo brain and whole body head-to-thighs data were acquired to demonstrate clinical image quality.

  6. A Clinical and Experimental Comparison of Time of Flight PET/MRI and PET/CT Systems.

    Science.gov (United States)

    Oprea-Lager, Daniela E; Yaqub, Maqsood; Pieters, Indra C; Reinhard, Rinze; van Moorselaar, Reindert J A; van den Eertwegh, Alfons J M; Hoekstra, Otto S; Lammertsma, Adriaan A; Boellaard, Ronald

    2015-10-01

    The purpose of the study was to compare image quality and quantitative accuracy of positron emission tomography/magnetic resonance imaging (PET/MRI) and PET/computed tomography (PET/CT) systems with time of flight PET gantries, using phantom and clinical studies. Identical phantom experiments were performed on both systems. Calibration, uniformity, and standardized uptake value (SUV) recovery were measured. A clinical PET/CT versus PET/MRI comparison was performed using [(18)F]fluoromethylcholine ([(18)F]FCH). Calibration accuracy and image uniformity were comparable between systems. SUV recovery met EANM/EARL requirements on both scanners. Thirty-four lesions with comparable PET image quality were identified. Lesional SUVmax differences of 4 ± 26% between PET/MRI and PET/CT data were observed (R (2) = 0.79, slope = 1.02). In healthy tissues, PET/MRI-derived SUVs were 16 ± 11% lower than on PET/CT (R (2) = 0.98, slope = 0.86). PET/MRI and PET/CT showed comparable performance with respect to calibration accuracy, image uniformity, and SUV recovery. [(18)F]FCH uptake values for both healthy tissues and lesions corresponded reasonably well between MR- and CT-based systems, but only in regions free of MR-based attenuation artifacts.

  7. Importance of PET/CT in lymphoma diagnostics; Stellenwert der PET/CT in der Lymphomdiagnostik

    Energy Technology Data Exchange (ETDEWEB)

    Afshar-Oromieh, A.; Kratochwil, C.; Haberkorn, U.; Giesel, F.L. [Universitaetsklinikum Heidelberg, Abteilung fuer Nuklearmedizin, Radiologische Klinik, Heidelberg (Germany)

    2012-04-15

    Staging or re-staging of lymphomas using conventional imaging modalities is based on morphological changes, usually on the diameter of lesions. However, vitality of tumors cannot be evaluated. In this context computed tomography (CT) has been used as a standard modality. Since the introduction of positron emission tomography (PET), evaluation of tumor vitality has become possible. Moreover PET/CT hybrid scanners were brought onto the market one decade ago. The fluorodeoxyglucose (FDG) PET/CT technique is now accepted as one of the most accurate modalities in the diagnosis of aggressive lymphomas due to a high FDG uptake (overall accuracy > 90%, sensitivity >90%). However, indolent lymphomas suffer from lower FDG uptake due to a moderate metabolic activity. After the introduction of PET/CT hybrid imaging the specificity of this diagnostic technique increased significantly compared to PET alone (from > 80% to > 90%). With the utilization of PET approximately 20% more lesions are detected when comparing to CT alone and in up to 15% of the patients this also results in a change of the therapeutic regime. As post-chemotherapy scar tissue usually persists for months, evaluation of vitality within residual bulks using FDG-PET can predict therapy response much earlier than CT, enabling therapy stratification. Other PET tracers apart from FDG have low impact in imaging of lymphomas and only the thymidine analogue fluorothymidine (FLT) is used in some cases for non-invasive measurement of proliferation. Despite the capability of FDG-PET/CT there is no evidence that the improvement in diagnostics is translated into a better patient outcome and therefore warrants the high costs. False positive findings in PET can result in unnecessary treatment escalation with subsequent higher therapy-associated toxicity and costs. Some pitfalls can be avoided by scheduling PET scans carefully. As treatment-induced inflammation early after therapy can be misinterpreted as vital tumor tissue

  8. Positron emission tomography (PET): evaluation of chronic periaortitis

    National Research Council Canada - National Science Library

    Salvarani, Carlo; Pipitone, Nicolò; Versari, Annibale; Vaglio, Augusto; Serafini, Desiderio; Bajocchi, Gianluigi; Salvo, Diana; Buzio, Carlo; Greco, Paolo; Boiardi, Luigi

    2005-01-01

    ...)F-fluorodeoxyglucose-positron emission tomography (FDG-PET). A consecutive case series consisting of 7 patients with CP seen over a 3-year period and a control group of 14 patients with malignancy were evaluated with FDG-PET...

  9. Injuries, envenomations and stings from exotic pets.

    Science.gov (United States)

    Warwick, Clifford; Steedman, Catrina

    2012-07-01

    A variety of exotic vertebrate and invertebrate species are kept as 'pets' including fishes, amphibians (for example, frogs and toads), reptiles (turtles, crocodiles, lizards and snakes), birds, mammals (for example, primates, civets, and lions), and invertebrates (for example spiders, scorpions, and centipedes), and ownership of some of these animals is rising. Data for 2009-2011 suggest that the number of homes with reptiles rose by approximately 12.5%. Recent surveys, including only some of these animals, indicated that they might be present in around 18.6% of homes (equal to approximately 42 million animals of which around 40 million are indoor or outdoor fish). Many exotic 'pets' are capable of causing injury or poisoning to their keepers and some contacts prove fatal. We examined NHS Health Episode Statistics for England using selected formal categories for hospital admissions and bed days for 2004-2010 using the following categories of injury, envenomation or sting; bitten or struck by crocodile or alligator; bitten or crushed by other reptiles: contact with venomous snakes and lizards; contact with scorpions. Between 2004 and 2010 these data conservatively show a total of 760 full consultation episodes, 709 admissions and 2,121 hospital bed days were associated with injuries probably from exotic pets. Injuries, envenomations and stings from exotic pets constitute a small but important component of emerging medical problems. Greater awareness of relevant injuries and medical sequelae from exotic pet keeping may help medics formulate their clinical assessment and advice to patients.

  10. Rol del PET/CT en epilepsia

    Directory of Open Access Journals (Sweden)

    Dr. Ladrón De Guevara David

    2013-11-01

    Full Text Available El PET (Positron Emission Tomography con F18-Fluorodeoxiglucosa (FDG es un examen ampliamente utilizado en el estudio de epilepsia refractaria, constituyendo en la actualidad un pilar fundamental en la evaluación quirúrgica. El PET proporciona una traducción funcional de la lesión morfológica y puede pesquisar otras áreas epileptógenas temporales y extratemporales no visibles con los métodos tradicionales. Su alta sensibilidad y positividad aún con Resonancia Magnética (RM negativa, hace posible optar a la resección quirúrgica en pacientes que de otra manera no podrían operarse, obteniendo sujetos libres de crisis en hasta el 80% de las epilepsias temporales. El PET es realizado eminentemente en fase interictal y posee una sensibilidad de 90% en focos temporales y 50 a 70% en focos extratemporales. El PET “ictal” y el uso de radiofármacos distintos del F18-FDG son alternativas válidas en ciertos casos de epilepsia, especialmente extratemporal. Es posible que el uso del PET en epilepsia siga aumentando debido a la cada vez mayor disponibilidad del método y su consiguiente menor costo.

  11. [Microbiological conservation medicine and exotic pets].

    Science.gov (United States)

    Hassl, Andreas

    2004-01-01

    The keeping and the breeding of exotic pets in privacy is a hobby with increasing popularity in industrialised countries. The growing demand for animals usually imported from the tropics, the growing demand for unprofessionally bred feeder organisms, and the increasing number of cases of faulty caring behaviour lead to the creation of new infectiological niches in the interface between exotic pet--nurse--feed--vivarium. These niches are filled preferably by ubiquitous, facultative pathogenic, stress- and age-deduced opportunists with a broad host spectrum. On the one hand these extraordinary germ faunas, relating to their compositions, may generate broad relevance in human medicine, lead to bizarre clinical pictures in specific cases, and may contribute to a reduction of the mean span of life of exotic pets kept in human care. On the other hand the quantitative composition of the fauna may also be a direct measure of the degree of stress the pets are suffering in captivity. Thus, a professional designation of the germ fauna of an exotic pet may contribute to an optimisation of the captivity conditions.

  12. Fully 3D GPU PET reconstruction

    Energy Technology Data Exchange (ETDEWEB)

    Herraiz, J.L., E-mail: joaquin@nuclear.fis.ucm.es [Grupo de Fisica Nuclear, Departmento Fisica Atomica, Molecular y Nuclear, Universidad Complutense de Madrid (Spain); Espana, S. [Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, MA (United States); Cal-Gonzalez, J. [Grupo de Fisica Nuclear, Departmento Fisica Atomica, Molecular y Nuclear, Universidad Complutense de Madrid (Spain); Vaquero, J.J. [Departmento de Bioingenieria e Ingenieria Espacial, Universidad Carlos III, Madrid (Spain); Desco, M. [Departmento de Bioingenieria e Ingenieria Espacial, Universidad Carlos III, Madrid (Spain); Unidad de Medicina y Cirugia Experimental, Hospital General Universitario Gregorio Maranon, Madrid (Spain); Udias, J.M. [Grupo de Fisica Nuclear, Departmento Fisica Atomica, Molecular y Nuclear, Universidad Complutense de Madrid (Spain)

    2011-08-21

    Fully 3D iterative tomographic image reconstruction is computationally very demanding. Graphics Processing Unit (GPU) has been proposed for many years as potential accelerators in complex scientific problems, but it has not been used until the recent advances in the programmability of GPUs that the best available reconstruction codes have started to be implemented to be run on GPUs. This work presents a GPU-based fully 3D PET iterative reconstruction software. This new code may reconstruct sinogram data from several commercially available PET scanners. The most important and time-consuming parts of the code, the forward and backward projection operations, are based on an accurate model of the scanner obtained with the Monte Carlo code PeneloPET and they have been massively parallelized on the GPU. For the PET scanners considered, the GPU-based code is more than 70 times faster than a similar code running on a single core of a fast CPU, obtaining in both cases the same images. The code has been designed to be easily adapted to reconstruct sinograms from any other PET scanner, including scanner prototypes.

  13. PET/MR: Yet another Tesla?

    Science.gov (United States)

    Schwaiger, Markus; Kunze, Karl; Rischpler, Christoph; Nekolla, Stephan G

    2017-06-01

    After the successful introduction of PET/CT as a multimodality imaging technique, PET/MR has subsequently emerged as an attractive instrumentation for applications in neurology, oncology, and cardiology. Simultaneous data acquisition combining structural, functional, and molecular imaging provides a unique platform to link various aspects of cardiac performance for the non-invasive characterization of cardiovascular disease phenotypes. Specifically, tissue characterization by MR techniques with and without contrast agents allows for functional parameters such as LGE, myocardial perfusion, and T1 maps as well as an estimate of extracellular volume. PET tracers excel by their high sensitivity and specificity, thus supplementing the functional tissue characterization by MRI. Although the clinical applications are yet to be validated , the first experience with PET/MR suggests future applications in the area of vascular imaging (unstable plaque) as well as in the characterization of inflammatory processes involving the heart. Ischemic heart disease can be comprehensively assessed by integrating regional function, perfusion, and viability. Future technical improvements leading to less costly PET/MR instrumentation are necessary to support routine clinical application of this promising technique in cardiology.

  14. FDG PET/CT in bone sarcoidosis.

    Science.gov (United States)

    Grozdic Milojevic, Isidora; Sobic-Saranovic, Dragana; Videnovic-Ivanov, Jelica; Saranovic, Djordjije; Odalovic, Strahinja; Artiko, Vera

    2016-03-29

    Bone sarcoidosis is rare manifestation of disease usually accompanied with pulmonary involvement. Until today, exact prevalence of bone sarcoidosis is not known, since reported prevalence varies widely depending on the studied population and the used diagnostic techniques. To determine the prevalence of bone involvement and distribution pattern in active chronic sarcoidosis by using FDG PET/CT. Between January 2010 and December 2011, 98 patients with chronic sarcoidosis and presence of prolonged symptoms or other findings suggestive of active disease were referred to FDG PET/CT examination. Active disease was found in 82 patients, and they all were screened for presence of bone sarcoidosis on FDG PET/CT. All patients also underwent MDCT and assessment of serum ACE level. Bone sarcoidosis was present in 18/82 patients with active sarcoidosis. FDG uptake in bones was focal in 8 (44.4%), diffuse in 6 (33.3%) and both diffuse and focal in 4 (22.2%) patients. CT indicated bone abnormalities only in 5% patients. Osseous involvement was present in: pelvis (61.1%), vertebrae (44.4%), ribs (27.8%) and bone marrow (16.7%). Some patients had two or more locations of disease. Follow-up FDG PET/CT showed normal findings in two patients, same localization of active disease in four patients and progression of disease in one. In patients with active chronic sarcoidosis 22% of patients had osseous abnormalities on FDG PET/CT that mostly were not detected on CT.

  15. EUV micropatterning for biocompatibility control of PET

    Science.gov (United States)

    Reisinger, B.; Fahrner, M.; Frischauf, I.; Yakunin, S.; Svorcik, V.; Fiedorowicz, H.; Bartnik, A.; Romanin, C.; Heitz, J.

    2010-08-01

    We have investigated the influence of oriented microstructures at modified polyethylene terephthalate (PET) on the adhesion and alignment of Chinese hamster ovary (CHO) cells. For surface modification, the PET foils were exposed to the radiation of a laser-plasma extreme ultraviolet (EUV) source based on a double-stream gas-puff target. The emission of the plasma was focused onto the samples by means of a gold-plated ellipsoidal collector. The spectrum of the focused radiation covered the wavelength range from 9 to 70 nm. The PET samples were irradiated with the EUV pulses at a repetition rate of 10 Hz in a high vacuum. For control experiments, PET samples were also irradiated in air with the light of a 193 nm ArF-excimer laser. Different kinds of surface microstructures were obtained depending on the EUV or laser fluence and pulse number, including oriented wall- and ripple-type structures with lateral structure periods of a few µm. The surface morphology of polymer samples after the irradiation was investigated using a scanning electron microscope (SEM). Changes in chemical surface structure of the irradiated samples were investigated using X-ray photoelectron spectroscopy (XPS). We demonstrated that the cells show good adhesion and align along oriented wall- and ripple-type microstructures on PET surfaces produced by the EUV irradiation.

  16. Positron Emission Tomography (PET) in Oncology

    Energy Technology Data Exchange (ETDEWEB)

    Gallamini, Andrea, E-mail: gallamini.a@ospedale.cuneo.it [Department of Research and Medical Innovation, Antoine Lacassagne Cancer Center, Nice University, Nice Cedex 2-06189 Nice (France); Zwarthoed, Colette [Department of Nuclear Medicine, Antoine Lacassagne Cancer Center, Nice University, Nice Cedex 2-06189 Nice (France); Borra, Anna [Hematology Department S. Croce Hospital, Via M. Coppino 26, Cuneo 12100 (Italy)

    2014-09-29

    Since its introduction in the early nineties as a promising functional imaging technique in the management of neoplastic disorders, FDG-PET, and subsequently FDG-PET/CT, has become a cornerstone in several oncologic procedures such as tumor staging and restaging, treatment efficacy assessment during or after treatment end and radiotherapy planning. Moreover, the continuous technological progress of image generation and the introduction of sophisticated software to use PET scan as a biomarker paved the way to calculate new prognostic markers such as the metabolic tumor volume (MTV) and the total amount of tumor glycolysis (TLG). FDG-PET/CT proved more sensitive than contrast-enhanced CT scan in staging of several type of lymphoma or in detecting widespread tumor dissemination in several solid cancers, such as breast, lung, colon, ovary and head and neck carcinoma. As a consequence the stage of patients was upgraded, with a change of treatment in 10%–15% of them. One of the most evident advantages of FDG-PET was its ability to detect, very early during treatment, significant changes in glucose metabolism or even complete shutoff of the neoplastic cell metabolism as a surrogate of tumor chemosensitivity assessment. This could enable clinicians to detect much earlier the effectiveness of a given antineoplastic treatment, as compared to the traditional radiological detection of tumor shrinkage, which usually takes time and occurs much later.

  17. Evaluation of various hepatic lesions with PET

    Energy Technology Data Exchange (ETDEWEB)

    Han, Chul Ju

    2000-12-01

    When a liver lesion is found in a PET image, differential diagnosis and analysis of the lesion is very important. We tried to analyze hepatic lesions found in PET. 53 patients with focal liver lesions (13 patients with HCC, 8 patients with cholangiocarcinoma (CC), 20 patients with liver metastasis, 5 patients with hemangioma, 7 patients with liver abscess, including 1 patient with liver candidiasis) were examined. Definitely high FDG uptake pattern were observed in 54% (7/13) of HCC, 100% (8/8) of CC, 95% (19/20) of metastatic liver cancer and 100% (7/7) of liver abscess. Therefore, PET was partially useful in the diagnosis of HCC, but it was very useful in the diagnosis of CC or liver metastasis or liver abscess. The contrast between lesions and surrounding liver background was very conspicuous in PET images of CC or liver metastasis or liver abscess, which suggests that PET might be used for the follow up and assessment of treatment response of these diseases.

  18. Clinical PET/MRI in neurooncology

    DEFF Research Database (Denmark)

    Marner, Lisbeth; Henriksen, Otto M; Lundemann, Michael

    2017-01-01

    PURPOSE: Magnetic resonance imaging (MRI) plays a key role in neurooncology, i.e., for diagnosis, treatment evaluation and detection of recurrence. However, standard MRI cannot always separate malignant tissue from other pathologies or treatment-induced changes. Advanced MRI techniques such as di......PURPOSE: Magnetic resonance imaging (MRI) plays a key role in neurooncology, i.e., for diagnosis, treatment evaluation and detection of recurrence. However, standard MRI cannot always separate malignant tissue from other pathologies or treatment-induced changes. Advanced MRI techniques...... number of sites. Several centers are now implementing hybrid PET/MRI systems allowing for multiparametric imaging, combining conventional MRI with advanced MRI and amino acid PET imaging. Neurooncology is an obvious focus area for PET/MR imaging. METHODS: Based on the literature and our experience from...... more than 300 PET/MRI examinations of brain tumors with (18)F-fluoro-ethyl-tyrosine, the clinical use of PET/MRI in adult and pediatric neurooncology is critically reviewed. RESULTS: Although the results are increasingly promising, the added value and range of indications for multiparametric imaging...

  19. 9 CFR 130.10 - User fees for pet birds.

    Science.gov (United States)

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false User fees for pet birds. 130.10... AGRICULTURE USER FEES USER FEES § 130.10 User fees for pet birds. (a) User fees for pet birds of U.S. origin returning to the United States, except pet birds of U.S. origin returning from Canada, are as follows...

  20. Pet therapy and increased socialization among elderly clients.

    Science.gov (United States)

    Combs, Allison

    2002-01-01

    Churchill et al.'s (1999) study supported the idea that pet therapy increased socialization and decreased agitation among persons with AD. This study could be used to support the group research utilization project on the use of pet therapy to increase socialization. Future research might concentrate on participants with varied ethnic backgrounds and varied clinical diagnoses. Some feasibility issues would be finding dogs or pets properly trained for therapy and finding nurses properly trained on the use of pet therapy.

  1. (18)F-Fluorodeoxyglucose PET/MR Imaging in Lymphoma.

    Science.gov (United States)

    Platzek, Ivan

    2016-10-01

    (18)F-Fluorodeoxyglucose (FDG) PET/MR imaging is feasible for initial staging and therapy response assessment in lymphoma. Although FDG PET/MR imaging is equivalent to FDG PET/CT for initial staging of lymphoma, not enough data are available with regard to other indications yet. Diffusion-weighted MR imaging is a promising addition to FDG PET/MR imaging, but has not been evaluated systematically. Copyright © 2016 Elsevier Inc. All rights reserved.

  2. Pet ownership and adolescent health: cross-sectional population study.

    Science.gov (United States)

    Mathers, Megan; Canterford, Louise; Olds, Tim; Waters, Elizabeth; Wake, Melissa

    2010-12-01

    To determine whether adolescent health and well-being are associated with having a pet in the household (any pet, or specifically dogs, cats or horses/ponies) or average daily time spent caring for/playing with pet(s). Design, setting and participants--Cross-sectional data from the third wave of the Health of Young Victorians Study (HOYVS), a school-based population study in Victoria, Australia. Predictors--Adolescent-reported pet ownership and average daily time spent caring for/playing with pet(s). Outcomes--Self-reported quality of life (KIDSCREEN); average 4-day daily physical activity level from a computerised diary; parent-proxy and self-reported physical and psychosocial health status (PedsQL); measured BMI status (not overweight, overweight, obese) and blood pressure. Statistical Analysis--Regression methods, adjusted for socio-demographic factors, and non-parametric methods. Household pet data were available for 928 adolescents (466 boys; mean age of 15.9 (SD 1.2) years). Most adolescents (88.7%) reported having a pet in their household. Of these, 75.1% reported no activity involving pets over the surveyed days. It appeared that neither owning a pet nor time spent caring for/playing with a pet was related, positively or negatively, to adolescent health or well-being. Despite high rates of pet ownership, adolescents had little interaction with pets. It appears that owning a pet and time spent caring for/playing with a pet was not clearly associated with adolescents' health or well-being. © 2010 The Authors. Journal of Paediatrics and Child Health © 2010 Paediatrics and Child Health Division (Royal Australasian College of Physicians).

  3. PET motion correction using PRESTO with ITK motion estimation

    Energy Technology Data Exchange (ETDEWEB)

    Botelho, Melissa [Institute of Biophysics and Biomedical Engineering, Science Faculty of University of Lisbon (Portugal); Caldeira, Liliana; Scheins, Juergen [Institute of Neuroscience and Medicine (INM-4), Forschungszentrum Jülich (Germany); Matela, Nuno [Institute of Biophysics and Biomedical Engineering, Science Faculty of University of Lisbon (Portugal); Kops, Elena Rota; Shah, N Jon [Institute of Neuroscience and Medicine (INM-4), Forschungszentrum Jülich (Germany)

    2014-07-29

    The Siemens BrainPET scanner is a hybrid MRI/PET system. PET images are prone to motion artefacts which degrade the image quality. Therefore, motion correction is essential. The library PRESTO converts motion-corrected LORs into highly accurate generic projection data [1], providing high-resolution PET images. ITK is an open-source software used for registering multidimensional data []. ITK provides motion estimation necessary to PRESTO.

  4. Combined PET-MRI of the abdomen; Kombinierte PET-MRT des Abdomens

    Energy Technology Data Exchange (ETDEWEB)

    Vag, Tibor; Eiber, M.; Schwaiger, M. [Technische Universitaet Muenchen, Klinik fuer Nuklearmedizin, Klinikum Rechts der Isar, Muenchen (Germany)

    2015-12-15

    The first fully integrated combined positron emission tomography-magnetic resonance imaging (PET-MRI) scanners have been clinically available since 2010. Large prospective studies regarding indications and diagnostic accuracy of this new modality are not yet available; however, preliminary studies have shown a higher diagnostic accuracy and confidence compared to PET-computed tomography (PET-CT) in regions where MRI is known to be superior to CT, such as the liver. The benefit of MRI in accurate lesion characterization and the additional value of diffusion-weighted imaging (DWI) as a complementary functional modality by means of the apparent diffusion coefficient (ADC) is apparent in entities with low tracer uptake (e. g. due to small size) and a decreased or absent accumulation pattern on PET. (orig.) [German] Seit 2010 sind die ersten voll integrierten Positronenemissionstomographie(PET)-MR-Scanner im klinischen Gebrauch. Obwohl es derzeit noch an empirischen Daten im Sinne groesserer und prospektiver Studien fehlt, implizieren erste Studien einen diagnostischen Mehrwert gegenueber der PET-CT in Regionen, in denen die MRT bekanntermassen der CT ueberlegen ist. Diese ist in der besseren morphologischen Charakterisierung begruendet, die insbesondere bei Laesionen mit geringer Tracerspeicherung (z. B. aufgrund der geringen Groesse) oder unbekanntem Speicherverhalten in der PET ausschlaggebend ist. Zudem steht der MRT eine komplementaere funktionelle Modalitaet in Form der Diffusionsbildgebung zur Verfuegung, die ueber die Berechnung des Apparent-diffusion-coefficient(ADC)-Werts eine weitere Einschaetzung des Gewebes geben kann. (orig.)

  5. Transmission of Bacterial Zoonotic Pathogens between Pets and Humans: The Role of Pet Food.

    Science.gov (United States)

    Lambertini, Elisabetta; Buchanan, Robert L; Narrod, Clare; Pradhan, Abani K

    2016-01-01

    Recent Salmonella outbreaks associated with dry pet food and treats raised the level of concern for these products as vehicle of pathogen exposure for both pets and their owners. The need to characterize the microbiological and risk profiles of this class of products is currently not supported by sufficient specific data. This systematic review summarizes existing data on the main variables needed to support an ingredients-to-consumer quantitative risk model to (1) describe the microbial ecology of bacterial pathogens in the dry pet food production chain, (2) estimate pet exposure to pathogens through dry food consumption, and (3) assess human exposure and illness incidence due to contact with pet food and pets in the household. Risk models populated with the data here summarized will provide a tool to quantitatively address the emerging public health concerns associated with pet food and the effectiveness of mitigation measures. Results of such models can provide a basis for improvements in production processes, risk communication to consumers, and regulatory action.

  6. Molecular cardiac PET besides FDG viability imaging; Molekulare Kardiale PET jenseits der FDG-Vitalitaetsdiagnostik

    Energy Technology Data Exchange (ETDEWEB)

    Lindner, O.; Burchert, W. [Universitaetsklinik der Ruhr-Univ. Bochum (Germany). Inst. fuer Radiologie, Nuklearmedizin und Molekulare Bildgebung, Herz- und Diabetszentrum NRW

    2009-06-15

    Molecular cardiac non F-18-FDG PET is currently based on perfusion imaging. It is of excellent diagnostic accuracy to detect coronary artery disease (CAD) and superior to perfusion SPECT. There is also evidence for its incremental prognostic value. The unique feature of PET to measure myocardial perfusion in absolute terms and in short time periods define its impact on cardiac imaging enabling both the evaluation of early changes in CAD and the accurate characterization of multivessel disease. Currently, all available PET perfusion tracers in Europe are cyclotron products. Rb-82, a generator product, is the most frequently employed perfusion tracer in the United States and cyclotron independent. This tracer has the potential to become an alternative in Europe soon. Nowadays, PET systems are manufactured as hybrid PET-CT scanners. In oncology, hybrid imaging revealed, that the combination of functional and morphological imaging is superior to the single components. In cardiology, the integration of perfusion PET imaging with CT calcium scoring and CT anatomy of the coronary arteries represents a similar constellation. Atherosclerotic plaque evaluation by combined PET-CT technique will be one of the most promising future applications with a potential immense impact on prophylaxis, diagnosis and therapy of CAD in the future. (orig.)

  7. Breast cancer detection using high-resolution breast PET compared to whole-body PET or PET/CT

    Energy Technology Data Exchange (ETDEWEB)

    Kalinyak, Judith E. [Naviscan Inc., San Diego, CA (United States); Berg, Wendie A. [University of Pittsburgh School of Medicine, Magee-Womens Hospital, Pittsburgh, PA (United States); Schilling, Kathy [Boca Raton Regional Hospital, Boca Raton, FL (United States); Madsen, Kathleen S. [Certus International, Inc., St. Louis, MO (United States); Narayanan, Deepa [Naviscan Inc., San Diego, CA (United States); National Cancer Institute, Bethesda, MD (United States); Tartar, Marie [Scripps Clinic, Scripps Green Hospital, La Jolla, CA (United States)

    2014-02-15

    To compare the performance characteristics of positron emission mammography (PEM) with those of whole-body PET (WBPET) and PET/CT in women with newly diagnosed breast cancer. A total of 178 women consented to PEM for presurgical planning in an IRB-approved protocol and also underwent either WBPET (n = 69) or PET/CT (n = 109) imaging, as per usual care at three centers. Tumor detection sensitivity, positive predictive values, and {sup 18}F-fluorodeoxyglucose (FDG) uptake were compared between the modalities. The effects of tumor size, type, and grade on detection were examined. The chi-squared or Fisher's exact tests were used to compare distributions between groups, and McNemar's test was used to compare distributions for paired data within subject groups, i.e. PEM versus WBPET or PEM versus PET/CT. The mean age of the women was 59 ± 12 years (median 60 years, range 26-89 years), with a mean invasive index tumor size of 1.6 ± 0.8 cm (median 1.5 cm, range 0.5-4.0 cm). PEM detected more index tumors (61/66, 92 %) than WBPET (37/66, 56 %; p < 0.001) or PET/CT (95/109, 87 % vs. 104/109, 95 % for PEM; p < 0.029). Sensitivity for the detection of additional ipsilateral malignancies was also greater with PEM (7/15, 47 %) than with WBPET (1/15, 6.7 %; p = 0.014) or PET/CT (3/23, 13 % vs. 13/23, 57 % for PEM; p = 0.003). Index tumor detection decreased with decreasing invasive tumor size for both WBPET (p = 0.002) and PET/CT (p < 0.001); PEM was not significantly affected (p = 0.20). FDG uptake, quantified in terms of maximum PEM uptake value, was lowest in ductal carcinoma in situ (median 1.5, range 0.7-3.0) and invasive lobular carcinoma (median 1.5, range 0.7-3.4), and highest in grade III invasive ductal carcinoma (median 3.1, range 1.4-12.9). PEM was more sensitive than either WBPET or PET/CT in showing index and additional ipsilateral breast tumors and remained highly sensitive for tumors smaller than 1 cm. (orig.)

  8. Impact of MR-safe headphones on PET attenuation in combined PET/MRI scans.

    Science.gov (United States)

    Büther, Florian; Vrachimis, Alexis; Becker, Anne; Stegger, Lars

    2016-12-01

    MR headphones are attenuation sources affecting PET quantification in hybrid PET/MRI. Despite potentially better patient communication, usage in PET/MRI scans is not approved by the vendor. This study aims to determine the impact of headphones on PET by means of phantom and patient scans. Additionally, the perceived benefit of using headphones was evaluated. A cylinder phantom was scanned without and with dedicated MR headphones in a PET/CT scanner. Headphone attenuation was additionally assessed in a clinical setup in 10 patients on a PET/MR scanner using F-18-fluoro-deoxy-glucose. The difference in tracer uptake with and without headset was determined for the various brain regions. Additionally, the patients were asked for differences in noise levels, patient comfort, communication quality, and preference. CT data revealed headphone attenuation values of 350-500 HU. Neglecting headphone attenuation leads to a decrease in PET values between the earcups of about 11 % when compared to the correctly reconstructed data. Regions further away from the headphones were less affected. Patient images demonstrated a decrease of 11 % on average in the cerebellum and temporal lobes, while other regions were less affected. No visual artefacts in the images were noticed. On average, no advantage in terms of noise and patient comfort and only slightly better quality of communication were imparted by the patients. Using headphones during PET/MR acquisition leads to a negative bias in brain uptake values without introducing obvious image artefacts. Since they lack benefits for the patients, they should be avoided if PET quantification of the brain is needed.

  9. F-18 fluorodeoxyglucose PET/CT and post hoc PET/MRI in a case of primary meningeal melanomatosis.

    Science.gov (United States)

    Lee, Hong Je; Ahn, Byeong-Cheol; Hwang, Seong Wook; Cho, Suk Kyong; Kim, Hae Won; Lee, Sang-Woo; Hwang, Jeong-Hyun; Lee, Jaetae

    2013-01-01

    Primary meningeal melanomatosis is a rare, aggressive variant of primary malignant melanoma of the central nervous system, which arises from melanocytes within the leptomeninges and carries a poor prognosis. We report a case of primary meningeal melanomatosis in a 17-year-old man, which was diagnosed with (18)F-fluorodeoxyglucose (F-18 FDG) PET/CT, and post hoc F-18 FDG PET/MRI fusion images. Whole-body F-18 FDG PET/CT was helpful in ruling out the extracranial origin of melanoma lesions, and in assessing the therapeutic response. Post hoc PET/MRI fusion images facilitated the correlation between PET and MRI images and demonstrated the hypermetabolic lesions more accurately than the unenhanced PET/CT images. Whole body F-18 FDG PET/CT and post hoc PET/MRI images might help clinicians determine the best therapeutic strategy for patients with primary meningeal melanomatosis.

  10. Pet Care Teaching Unit: 1st-3rd Grades.

    Science.gov (United States)

    Peninsula Humane Society, San Mateo, CA.

    Activities in this unit are designed to familiarize primary grade students with the responsibilities involved in pet ownership. Teaching plans are provided for a total of 12 lessons involving social studies, language arts, math, and health sciences. Activities adaptable for readers and non-readers focus on pet overpopulation, care of pets when…

  11. 50 CFR 36.36 - Sled dogs and household pets.

    Science.gov (United States)

    2010-10-01

    ... 50 Wildlife and Fisheries 6 2010-10-01 2010-10-01 false Sled dogs and household pets. 36.36... Sled dogs and household pets. The general trespass provisions of 50 CFR 26.21 shall not apply to household pets and sled, work, or pack dogs under the direct control of their owners or handlers, but such...

  12. Profound Encounters: Classroom Animals--More Than Responsible Pet Care.

    Science.gov (United States)

    Naherniak, Craig

    1995-01-01

    Discusses the benefits of a classroom pet. Presents guidelines to determine whether a classroom pet is really needed and some suggestions for improving existing conditions for animals you may already have. Includes chart for choosing the right pet, which compares the life span, size, diet, and pros and cons for guinea pigs, hamsters, rabbits,…

  13. 50 CFR 14.17 - Personally owned pet birds.

    Science.gov (United States)

    2010-10-01

    ... 50 Wildlife and Fisheries 1 2010-10-01 2010-10-01 false Personally owned pet birds. 14.17 Section 14.17 Wildlife and Fisheries UNITED STATES FISH AND WILDLIFE SERVICE, DEPARTMENT OF THE INTERIOR... Ports § 14.17 Personally owned pet birds. Any person may import a personally owned pet bird at any port...

  14. Effects of regularisation priors on dynamic PET Data

    Energy Technology Data Exchange (ETDEWEB)

    Caldeira, Liliana; Scheins, Juergen; Silva, Nuno da; Gaens, Michaela; Shah, N Jon [Institute of Neuroscience and Medicine-4, Forschungszentrum Juelich (Germany)

    2014-07-29

    Dynamic PET provides temporal information about tracer uptake. However, each PET frame has usually low statistics, resulting in noisy images. The goal is to study effects of prior regularisation on dynamic PET data. Quantification and noise in image-domain and time-domain as well as impact on parametric images is assessed.

  15. Social capital and pet ownership - A tale of four cities.

    Science.gov (United States)

    Wood, Lisa; Martin, Karen; Christian, Hayley; Houghton, Steve; Kawachi, Ichiro; Vallesi, Shannen; McCune, Sandra

    2017-12-01

    Pet ownership is significantly associated with higher levels of social capital.•Social capital was associated with pet ownership in the U.S. and Australia.•Results are not confined to dog owners nor dog walkers.•Pets are an under-recognized conduit for building social capital.

  16. The Psychological Effect of Pet-Ownership on Reading Achievement.

    Science.gov (United States)

    Hamtil, Rosemary

    A study examined the possible influence that pets may have on children's reading achievement. Subjects, 61 students from three third-grade classes in an urban school, completed a questionnaire about pet ownership. Responses were compiled and score values established to recognize the length of time the child had owned the pet and how much…

  17. PET/MRI for Oncologic Brain Imaging

    DEFF Research Database (Denmark)

    Rausch, Ivo; Rischka, Lucas; Ladefoged, Claes N

    2017-01-01

    by Siemens Healthcare). As a reference, AC maps were derived from patient-specific CT images (CTref). PET data were reconstructed using standard settings after AC with all 4 AC methods. We report changes in diagnosis for all brain tumor patients and the following relative differences values (RDs...... of the whole brain and 10 anatomic regions segmented on MR images.Results:For brain tumor imaging (A and B), the standard PET-based diagnosis was not affected by any of the 3 MR-AC methods. For A, the average RDs of SUVmeanwere -10%, -4%, and -3% and of the VOIs 1%, 2%, and 7% for DIXON, UTE, and BD......, respectively.Conclusion:The diagnostic reading of PET/MR patients with brain tumors did not change with the chosen AC method. Quantitative accuracy of SUVs was clinically acceptable for UTE- and BD-AC for group A, whereas for group B BD was in accordance with CTref. Nevertheless, for the quantification...

  18. Immuno-PET for Clinical Theranostic Approaches

    Directory of Open Access Journals (Sweden)

    Clément Bailly

    2016-12-01

    Full Text Available Recent advances in molecular characterization of tumors have allowed identification of new molecular targets on tumor cells or biomarkers. In medical practice, the identification of these biomarkers slowly but surely becomes a prerequisite before any treatment decision, leading to the concept of personalized medicine. Immuno-positron emission tomography (PET fits perfectly with this approach. Indeed, monoclonal antibodies (mAbs labelled with radionuclides represent promising probes for theranostic approaches, offering a non-invasive solution to assess in vivo target expression and distribution. Immuno-PET can potentially provide useful information for patient risk stratification, diagnosis, selection of targeted therapies, evaluation of response to therapy, prediction of adverse effects or for titrating doses for radioimmunotherapy. This paper reviews some aspects and recent developments in labelling methods, biological targets, and clinical data of some novel PET radiopharmaceuticals.

  19. Immuno-PET for Clinical Theranostic Approaches.

    Science.gov (United States)

    Bailly, Clément; Cléry, Pierre-François; Faivre-Chauvet, Alain; Bourgeois, Mickael; Guérard, François; Haddad, Ferid; Barbet, Jacques; Chérel, Michel; Kraeber-Bodéré, Françoise; Carlier, Thomas; Bodet-Milin, Caroline

    2016-12-28

    Recent advances in molecular characterization of tumors have allowed identification of new molecular targets on tumor cells or biomarkers. In medical practice, the identification of these biomarkers slowly but surely becomes a prerequisite before any treatment decision, leading to the concept of personalized medicine. Immuno-positron emission tomography (PET) fits perfectly with this approach. Indeed, monoclonal antibodies (mAbs) labelled with radionuclides represent promising probes for theranostic approaches, offering a non-invasive solution to assess in vivo target expression and distribution. Immuno-PET can potentially provide useful information for patient risk stratification, diagnosis, selection of targeted therapies, evaluation of response to therapy, prediction of adverse effects or for titrating doses for radioimmunotherapy. This paper reviews some aspects and recent developments in labelling methods, biological targets, and clinical data of some novel PET radiopharmaceuticals.

  20. Psychiatric investigation of 18 bereaved pet owners.

    Science.gov (United States)

    Kimura, Yuya; Kawabata, Hidenobu; Maezawa, Masaji

    2011-08-01

    This survey explores the grief associated with the loss of a pet, and was carried out using a self-administered questionnaire. The questionnaires were handed out to 50 bereaved pet owners attending a public animal cremation service, and we received 18 responses. Participants responded within 0 to 44 (median 4) days of the death of their pet. Although most mental health problems immediately following mourning are presumed to be normal grief reactions, on the basis of several psychiatric scales, 8 of the 16 valid responses indicated depression and/or neurosis. Statistical analyses showed that the following factors were significantly associated with grief reactions: age of owner, other stressful life events, family size, age of deceased animal, rearing place, and preliminary veterinary consultation.

  1. Cardiac sympathetic neuronal imaging using PET

    Energy Technology Data Exchange (ETDEWEB)

    Lautamaeki, Riikka; Tipre, Dnyanesh [Johns Hopkins University, Division of Nuclear Medicine, Russell H. Morgan Department of Radiology and Radiological Science, Baltimore, MD (United States); Bengel, Frank M. [Johns Hopkins University, Division of Nuclear Medicine, Russell H. Morgan Department of Radiology and Radiological Science, Baltimore, MD (United States); Cardiovascular Nuclear Medicine, Baltimore, MD (United States)

    2007-06-15

    Balance of the autonomic nervous system is essential for adequate cardiac performance, and alterations seem to play a key role in the development and progression of various cardiac diseases. PET imaging of the cardiac autonomic nervous system has advanced extensively in recent years, and multiple pre- and postsynaptic tracers have been introduced. The high spatial and temporal resolution of PET enables noninvasive quantification of neurophysiologic processes at the tissue level. Ligands for catecholamine receptors, along with radiolabeled catecholamines and catecholamine analogs, have been applied to determine involvement of sympathetic dysinnervation at different stages of heart diseases such as ischemia, heart failure, and arrhythmia. This review summarizes the recent findings in neurocardiological PET imaging. Experimental studies with several radioligands and clinical findings in cardiac dysautonomias are discussed. (orig.)

  2. Wildlife, Exotic Pets, and Emerging Zoonoses1

    Science.gov (United States)

    Belotto, Albino; Meslin, François-Xavier

    2007-01-01

    Most emerging infectious diseases are zoonotic; wildlife constitutes a large and often unknown reservoir. Wildlife can also be a source for reemergence of previously controlled zoonoses. Although the discovery of such zoonoses is often related to better diagnostic tools, the leading causes of their emergence are human behavior and modifications to natural habitats (expansion of human populations and their encroachment on wildlife habitat), changes in agricultural practices, and globalization of trade. However, other factors include wildlife trade and translocation, live animal and bushmeat markets, consumption of exotic foods, development of ecotourism, access to petting zoos, and ownership of exotic pets. To reduce risk for emerging zoonoses, the public should be educated about the risks associated with wildlife, bushmeat, and exotic pet trades; and proper surveillance systems should be implemented. PMID:17370509

  3. A comparison of 18F-FDG PET/MR with PET/CT in pulmonary tuberculosis.

    Science.gov (United States)

    Thomas, Benjamin A; Molton, James S; Leek, Francesca; Pang, Yan; Totman, John J; Paton, Nicholas I; Townsend, David W

    2017-11-01

    PET/computed tomography (CT) has been shown to detect lesions in patients with pulmonary tuberculosis (PTB) and may be useful for assessing PTB disease in clinical research studies. However, radiation dose is of concern for clinical research in individuals with an underlying curable disease. This study aimed to determine whether PET/MR is equivalent to PET/CT in PTB. Ten patients with microbiologically confirmed PTB were recruited. Patients received 129.0±4.1 MBq of fluorine-18-fluorodeoxyglucose. Five of the 10 patients underwent a PET/MR scan, followed by PET/CT. The remaining five were first imaged on the PET/CT, followed by the PET/MRI. PET acquisition began at 66.7±14.4 min (mean±SD) after injection when performing PET/MR first (PET/CT: 117.2±5.6 min) and 92.4±7.6 min when patients were imaged on PET/MR second (PET/CT: 61.1±3.9 min). PET data were reconstructed iteratively with Ordinary-Poisson Ordered-Subset Expectation-Maximization and reconstruction parameters were matched across the two scanners. A visual lesion detection task and a standardized uptake value (SUV) analysis were carried out. The CT Hounsfield unit values of PTB lesions were also compared with MR-based attenuation correction mu-map tissue classes. A total of 108 PTB lesions were detected on PET/MR and 112 on PET/CT. SUV analysis was carried out on 50 of these lesions that were observed with both modalities. Mean standardized uptake value (SUVmean) and maximum standardized uptake value (SUVmax) were significantly lower on PET/MR (SUVmean: 2.6±1.4; SUVmax: 4.3±2.5) than PET/CT (SUVmean: 3.5±1.5; SUVmax: 5.3±2.4). PET/MR visual performance was shown to be comparable to PET/CT in terms of the number of PTB lesions detected. SUVs were significantly lower on PET/MR. Dixon-based attenuation correction underestimates the linear attenuation coefficient of PTB lesions, resulting in lower SUVs compared with PET/CT. However, the use of PET/MR to measure the response of lung lesions

  4. SU-E-I-84: A Novel Approach for the Attenuation Correction of PET Data in PET/MR Systems.

    Science.gov (United States)

    Chang, T; Clark, J; Mawlawi, O

    2012-06-01

    To evaluate the use of non-attenuated PET images (PET-NAC) as a means for the attenuation correction (AC) of PET images in PET/MR systems. A 3 step iterative segmentation process is proposed. The first step is used to segment the body contour from the NAC PET images using an active contour algorithm (Kass et al., Int J Comput Vision, 321-331 (1988)). The second step was to segment the lung region from the resultant image using an optimal thresholding approach (Xu et al., IEEE T Nucl Sci, 43, 331-336 (1996)). The purpose of the third step was to delineate parts of the heart and liver from the lung contour using a region growing approach since these parts were unavoidably included in the lung contour of the second step. Finally the attenuation coefficients of the bed were included based on CT images to eliminate the impact of the couch on the accuracy of AC. The final attenuation map was then used to AC the raw PET data and Result in a final PET image (PET-IAC). To assess the proposed segmentation approach, a phantom and six patients were scanned on a GE Discovery-RX PET/CT scanner. PET-IAC was then generated from PET- NAC using the proposed approach and compared to those of CT-AC PET (PET-CTAC). Visual inspection and SUV measurements between PET-IAC and the PET-CTAC for phantom and patient studies were performed to assess the accuracy of image quantification. Visual inspection showed a small difference between the PET-IAC and PET-CTAC. PET-IAC tumor SUVs were on average equal to 103±9% compared to the SUVs from the PET-CTAC in the phantom study, and 110±7% in the patient studies. Preliminary results suggest that PET-NAC for the AC of PET images is feasible in the clinic. Such an approach can potentially be an alternative method of MR-based AC in PET/MR imaging. © 2012 American Association of Physicists in Medicine.

  5. Comparison of PET/MRI With PET/CT in the Evaluation of Disease Status in Lymphoma.

    Science.gov (United States)

    Afaq, Asim; Fraioli, Francesco; Sidhu, Harbir; Wan, Simon; Punwani, Shonit; Chen, Shih-Hsin; Akin, Oguz; Linch, David; Ardeshna, Kirit; Lambert, Jonathan; Miles, Kenneth; Groves, Ashley; Kayani, Irfan

    2017-01-01

    The primary aim was to compare the diagnostic performance of PET/MRI (performed with basic anatomical MRI sequences) in detecting sites of disease in adult patients with lymphoma compared with the current standard of care, PET/CT. Secondary aims were to assess the additional value of diffusion-weighted imaging to PET/MRI in disease detection and to evaluate the relationship between the standardized uptake value on PET/MR and the apparent diffusion coefficient on diffusion-weighted imaging. Sixty-eight studies in 66 consecutive patients with histologically proven Hodgkin or non-Hodgkin lymphoma were prospectively evaluated. Each patient had whole body PET/CT, followed by whole body PET/MR. Two experienced readers independently evaluated the PET/MRI studies, and two other experienced readers independently evaluated PET/CT. Site of lymphoma involvement and SUVmax at all nodal sites more avid than background liver were recorded. Readers provided stage (in baseline cases) and disease status (remission vs active disease). The apparent diffusion coefficient mean value corresponding to the most avid PET site of disease was recorded. Ninety-five nodal and 8 extranodal sites were identified on both PET/CT and PET/MRI. In addition, 3 nodal and 1 extranodal sites were identified on PET/MRI. For positive lesion detection, reader agreement in PET/MR was perfect between the 2 readers and almost perfect between PET/CT and PET/MR (k > 0.978). Intermodality agreement between PET/CT and PET/MRI was also near perfect to perfect for staging/disease status k = (0.979-1.000). SUVmax from PET/CT and PET/MRI correlated significantly (Spearman rho correlation coefficient, 0.842; P PET/MRI is a reliable alternative to PET/CT in the evaluation of patients with lymphoma. Diffusion-weighted imaging did not alter diagnostic accuracy. With comparable accuracy in detection of disease sites and added benefit of radiation dose reduction, PET/MRI has a potential to become part of routine lymphoma

  6. Hybrid FDG-PET/MR compared to FDG-PET/CT in adult lymphoma patients.

    Science.gov (United States)

    Atkinson, Wendy; Catana, Ciprian; Abramson, Jeremy S; Arabasz, Grae; McDermott, Shanaugh; Catalano, Onofrio; Muse, Victorine; Blake, Michael A; Barnes, Jeffrey; Shelly, Martin; Hochberg, Ephraim; Rosen, Bruce R; Guimaraes, Alexander R

    2016-07-01

    The goal of this study is to evaluate the diagnostic performance of simultaneous FDG-PET/MR including diffusion compared to FDG-PET/CT in patients with lymphoma. Eighteen patients with a confirmed diagnosis of non-Hodgkin's (NHL) or Hodgkin's lymphoma (HL) underwent an IRB-approved, single-injection/dual-imaging protocol consisting of a clinical FDG-PET/CT and subsequent FDG-PET/MR scan. PET images from both modalities were reconstructed iteratively. Attenuation correction was performed using low-dose CT data for PET/CT and Dixon-MR sequences for PET/MR. Diffusion-weighted imaging was performed. SUVmax was measured and compared between modalities and the apparent diffusion coefficient (ADC) using ROI analysis by an experienced radiologist using OsiriX. Strength of correlation between variables was measured using the Pearson correlation coefficient (r p). Of the 18 patients included in this study, 5 had HL and 13 had NHL. The median age was 51 ± 14.8 years. Sixty-five FDG-avid lesions were identified. All FDG-avid lesions were visible with comparable contrast, and therefore initial and follow-up staging was identical between both examinations. SUVmax from FDG-PET/MR [(mean ± sem) (21.3 ± 2.07)] vs. FDG-PET/CT (mean 23.2 ± 2.8) demonstrated a strongly positive correlation [r s = 0.95 (0.94, 0.99); p PET/MR [r = 0.17(-0.07, 0.66); p = 0.09]. FDG-PET/MR offers an equivalent whole-body staging examination as compared with PET/CT with an improved radiation safety profile in lymphoma patients. Correlation of ADC to SUVmax was weak, understating their lack of equivalence, but not undermining their potential synergy and differing importance.

  7. SPECT and PET imaging in epilepsia; SPECT und PET in der Diagnostik von Epilepsien

    Energy Technology Data Exchange (ETDEWEB)

    Landvogt, C. [Mainz Univ. (Germany). Klinik und Poliklinik fuer Nuklearmedizin

    2007-09-15

    In preoperative localisation of epileptogenic foci, nuclear medicine diagnostics plays a crucial role. FDG-PET is used as first line diagnostics. In case of inconsistent MRI, EEG and FDG-PET findings, {sup 11}C-Flumazenil-PET or ictal and interictal perfusion-SPECT should be performed. Other than FDG, Flumazenil can help to identify the extend of the region, which should be resected. To enhance sensitivity and specificity, further data analysis using voxelbased statistical analyses or SISCOM (substraction ictal SPECT coregistered MRI) should be performed.

  8. Limitations of FDG-PET and FDG-PET with computed tomography for detecting synchronous cancer in pharyngeal cancer.

    Science.gov (United States)

    Suzuki, Hidenori; Hasegawa, Yasuhisa; Terada, Akihiro; Ogawa, Tetsuya; Hyodo, Ikuo; Suzuki, Masahiro; Nakashima, Tsutomu; Tamaki, Tsuneo; Nishio, Masami

    2008-11-01

    To analyze the ability of fluorine-18 fluorodeoxyglucose positron emission tomography (FDG-PET) and the fusion of FDG-PET with computed tomography (FDG-PET/CT) to detect synchronous upper gastrointestinal tract (UGI) cancer in newly diagnosed pharyngeal squamous cell carcinoma (SCC). Synchronous UGI cancer is a significant problem in treating pharyngeal SCC, particularly for Japanese populations reported to be at high risk. Good results have been reported from the use of FDG-PET and FDG-PET/CT in staging head and neck SCC (HNSCC). An additional advantage is that both techniques are expected to prove useful in detecting synchronous cancer. Retrospective analysis of medical records. Aichi Cancer Center, Nagoya, Japan. Forty-three Japanese patients with pharyngeal SCC were assessed for the ability of FDG-PET and FDG-PET/CT to detect synchronous UGI cancer via a comparison with UGI Lugol chromoendoscopy. The patients had undergone 17 FDG-PET and 26 FDG-PET/CT scans before treatment. Sensitivity of FDG-PET and FDG-PET/CT to detect synchronous UGI cancer. Pathologically, 6 patients with esophageal SCC (14%) and 4 with stomach adenocarcinoma (9%) were diagnosed on the basis of suspect lesions detected by UGI Lugol chromoendoscopy. One patient was found to have stage T2 esophageal cancer by FDG-PET/CT, but no patients had UGI cancer. The sensitivity of detecting T1 UGI cancer by FDG-PET and FDG-PET/CT was 0%. The choice of diagnostic technique must be based on the site and histologic characteristics of the synchronous tumor. Although FDG-PET and FDG-PET/CT are still the preferred techniques for staging HNSCC, neither replaces Lugol chromoendoscopy for detecting synchronous UGI cancer in high-risk populations.

  9. Preoperative staging of non-small cell lung cancer: prospective comparison of PET/MR and PET/CT

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Sang Min [Seoul National University College of Medicine, Department of Radiology, Seoul (Korea, Republic of); Seoul National University Medical Research Center, Institute of Radiation Medicine, Seoul (Korea, Republic of); University of Ulsan College of Medicine, Department of Radiology and Research Institute of Radiology, Seoul (Korea, Republic of); Goo, Jin Mo; Park, Chang Min [Seoul National University College of Medicine, Department of Radiology, Seoul (Korea, Republic of); Seoul National University Medical Research Center, Institute of Radiation Medicine, Seoul (Korea, Republic of); Seoul National University College of Medicine, Cancer Research Institute, Seoul (Korea, Republic of); Yoon, Soon Ho [Seoul National University College of Medicine, Department of Radiology, Seoul (Korea, Republic of); Seoul National University Medical Research Center, Institute of Radiation Medicine, Seoul (Korea, Republic of); Paeng, Jin Chul; Cheon, Gi Jeong [Seoul National University College of Medicine, Department of Nuclear Medicine, Seoul (Korea, Republic of); Kim, Young Tae [Seoul National University College of Medicine, Cancer Research Institute, Seoul (Korea, Republic of); Seoul National University College of Medicine, Department of Thoracic and Cardiovascular Surgery, Seoul (Korea, Republic of); Park, Young Sik [Seoul National University Hospital, Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Seoul (Korea, Republic of); Seoul National University College of Medicine, Department of Internal Medicine, Seoul (Korea, Republic of)

    2016-11-15

    To prospectively compare the accuracies of PET/MR and PET/CT in the preoperative staging of non-small cell lung cancer (NSCLC). Institutional review board approval and patients' informed consents were obtained. 45 patients with proven or radiologically suspected lung cancer which appeared to be resectable on CT were enrolled. PET/MR was performed for the preoperative staging of NSCLC followed by PET/CT without contrast enhancement on the same day. Dedicated MR images including diffusion weighted images were obtained. Readers assessed PET/MR and PET/CT with contrast-enhanced CT. Accuracies of PET/MR and PET/CT for NSCLC staging were compared. Primary tumour stages (n = 40) were correctly diagnosed in 32 patients (80.0 %) on PET/MR and in 32 patients (80.0 %) on PET/CT (P = 1.0). Node stages (n = 42) were correctly determined in 24 patients (57.1 %) on PET/MR and in 22 patients (52.4 %) on PET/CT (P = 0.683). Metastatic lesions in the brain, bone, liver, and pleura were detected in 6 patients (13.3 %). PET/MR missed one patient with pleural metastasis while PET/CT missed one patient with solitary brain metastasis and two patients with pleural metastases (P = 0.480). This study demonstrated that PET/MR in combination with contrast-enhanced CT was comparable to PET/CT in the preoperative staging of NSCLC while reducing radiation exposure. (orig.)

  10. Caracterização de resíduos de copolímeros de etileno-acetato de vinila - EVA Characterization of ethylene-vinyl acetate copolymer (EVA residues

    Directory of Open Access Journals (Sweden)

    Ademir J. Zattera

    2005-03-01

    Full Text Available O poli[(etileno-co-(acetato de vinila] (EVA possui grande aplicação na indústria calçadista, sendo utilizado na confecção de placas expandidas para posterior corte de palmilhas e entressolas. Estudos realizados na região sul do Brasil mostraram que os resíduos gerados pela indústria calçadista foram superiores a 200 toneladas/mês em 2001, sendo o maior volume oriundo de recortes de placas expandidas. Por isso, o objetivo deste trabalho foi o de caracterizar resíduos de EVA de chapas expandidas, visando à reciclagem mecânica desse material. Análises em MEV demonstraram que o resíduo de EVA apresenta uma morfologia microcelular que é destruída após o processo de moagem. O resíduo de EVA moído apresenta duas fases, uma reticulada (matriz e uma não-reticulada (dispersa. O resíduo de EVA apresentou teor de gel de aproximadamente 75% em massa, cerca de 20% em massa de acetato de vinila (VAc, fora processado a partir de EVA com aproximadamente 28% de VAc e possui teor de carga inorgânica de 20% em massa, segundo análises em TGA. O EVA resíduo apresentou maiores valores de módulo elástico e de dureza, e menores valores de elongação na ruptura e de resistência ao impacto Izod. O custo energético da moagem do resíduo de EVA foi calculado como sendo inferior a 5% do valor do EVA virgem.Poly[(ethylene-co-(vinyl acetate] (EVA has large application in the shoes industries, especially as expanded sheets, in order to produce insoles and innersoles. Studies carried out in the south region of Brazil in 2001 have demonstrated that the residues generated by shoes industries were higher than 200 ton/month, the major part of which is composed by EVA expanded sheets. With this in mind, the objective of this work was to characterize the residues of expanded EVA and also to analyze the milling cost in order to make the recycling possible. The EVA residues presented originally a microcellular structure, which was destroyed after milling

  11. PET imaging in patients with Modic changes

    Energy Technology Data Exchange (ETDEWEB)

    Albert, H.B.; Manniche, C. [Univ. of Southern Denmark, Funen (Denmark). Back Research Centre; Petersen, H.; Hoeilund-Carlsen, P.F. [Odense University Hospital, Univ. of Southern Denmark (Denmark). Dept. of Nuclear Medicine

    2009-07-01

    The aim of this study was via PET imaging to reveal if any highly metabolic processes were occurring in Modic changes type 1 and/or in the adjacent discs. Modic changes (MC) are signal changes in the vertebral endplate and body visualised by magnetic resonance imaging (MRI). MC are strongly associated with low back pain (LBP). MC type 1 appear to be inflammation on MRI, and histological and biochemical findings make it highly likely that an inflammation is present. Though MC is painful no known treatment is available, and it is unknown which entities affect the progress or regress of MC. The changes observed on MRI are slow and take months to develop, but faster changes in the metabolism might provide a platform for monitoring patients. Patients from The Back Centre Funen, with low back pain in the area of L1 to S1, MC type 1 in L1 to L5, and a previous herniated lumbar disc. All patients had a PET scan using FDG ({sup 18}F-fluorodeoxyglucose) as tracer. Included in the study were 11 patients, 4 women and 7 men, mean age 48.1 year (range 20-65). All MC were situated in the vertebrae both above and below the previously herniated disc/discs. Ten patients had MC at 1 level, and 1 had MC at 2 levels. The affected levels were 1 at L2/L3, 6 at L4 /L5, and 5 at L5/S1. All had a previous disc herniation and MC larger than 4 mm in diameter. Technically satisfactory PET scans were obtained. However, PET imaging showed no increases in metabolism in any vertebra or disc of any patient. Modic type 1 changes do not reveal themselves by showing increased metabolism with ordinary FDG PET imaging. PET tracers illuminating inflammation are being developed and hopefully may become more successful. (orig.)

  12. PET and SPECT imaging in veterinary medicine.

    Science.gov (United States)

    LeBlanc, Amy K; Peremans, Kathelijne

    2014-01-01

    Veterinarians have gained increasing access to positron emission tomography (PET and PET/CT) imaging facilities, allowing them to use this powerful molecular imaging technique for clinical and research applications. SPECT is currently being used more in Europe than in the United States and has been shown to be useful in veterinary oncology and in the evaluation of orthopedic diseases. SPECT brain perfusion and receptor imaging is used to investigate behavioral disorders in animals that have interesting similarities to human psychiatric disorders. This article provides an overview of the potential applications of PET and SPECT. The use of commercially available and investigational PET radiopharmaceuticals in the management of veterinary disease has been discussed. To date, most of the work in this field has utilized the commercially available PET tracer, (18)F-fluorodeoxyglucose for oncologic imaging. Normal biodistribution studies in several companion animal species (cats, dogs, and birds) have been published to assist in lesion detection and interpretation for veterinary radiologists and clinicians. Studies evaluating other (18)F-labeled tracers for research applications are underway at several institutions and companion animal models of human diseases are being increasingly recognized for their value in biomarker and therapy development. Although PET and SPECT technologies are in their infancy for clinical veterinary medicine, increasing access to and interest in these applications and other molecular imaging techniques has led to a greater knowledge and collective body of expertise for veterinarians worldwide. Initiation and fostering of physician-veterinarian collaborations are key components to the forward movement of this field. Copyright © 2014 Elsevier Inc. All rights reserved.

  13. PRODUCTION CONSIDERATIONS FOR THE CLASSICAL PET NUCLIDES.

    Energy Technology Data Exchange (ETDEWEB)

    FINN,R.; SCHLYER,D.

    2001-06-25

    Nuclear Medicine is the specialty of medical imaging, which utilizes a variety of radionuclides incorporated into specific compounds for diagnostic imaging and therapeutic applications. During recent years, research efforts associated with this discipline have concentrated on the decay characteristics of particular radionuclides and the design of unique radiolabeled tracers necessary to achieve time-dependent molecular images. The specialty is expanding with specific Positron emission tomography (PET) and SPECT radiopharmaceuticals allowing for an extension from functional process imaging in tissue to pathologic processes and nuclide directed treatments. PET is an example of a technique that has been shown to yield the physiologic information necessary for clinical oncology diagnoses based upon altered tissue metabolism. Most PET drugs are currently produced using a cyclotron at locations that are in close proximity to the hospital or academic center at which the radiopharmaceutical will be administered. In November 1997, a law was enacted called the Food and Drug Administration Modernization Act of 1997 which directed the Food and Drug Administration (FDA) to establish appropriate procedures for the approval of PET drugs in accordance with section 505 of the Federal Food, Drug, and Cosmetic Act and to establish current good manufacturing practice requirements for such drugs. At this time the FDA is considering adopting special approval procedures and cGMP requirements for PET drugs. The evolution of PET radiopharmaceuticals has introduced a new class of ''drugs'' requiring production facilities and product formulations that must be closely aligned with the scheduled clinical utilization. The production of the radionuclide in the appropriate synthetic form is but one critical component in the manufacture of the finished radiopharmaceutical.

  14. The effect of patient positioning aids on PET quantification in PET/MR imaging

    Energy Technology Data Exchange (ETDEWEB)

    Mantlik, Frederic; Hofmann, Matthias [University of Tuebingen, Laboratory for Preclinical Imaging and Imaging Technology of the Werner Siemens-Foundation, Department of Radiology, Tuebingen (Germany); Max Planck Institute for Biological Cybernetics, Tuebingen (Germany); Werner, Matthias K.; Sauter, Alexander [University Hospital, Department of Diagnostic and Interventional Radiology, Tuebingen (Germany); Kupferschlaeger, Juergen [University Hospital, Department of Nuclear Medicine, Tuebingen (Germany); Schoelkopf, Bernhard [Max Planck Institute for Biological Cybernetics, Tuebingen (Germany); Pichler, Bernd J. [University of Tuebingen, Laboratory for Preclinical Imaging and Imaging Technology of the Werner Siemens-Foundation, Department of Radiology, Tuebingen (Germany); Beyer, Thomas [University Hospital, Imaging Science Institute, Tuebingen (Germany)

    2011-05-15

    Clinical PET/MR requires the use of patient positioning aids to immobilize and support patients for the duration of the combined examination. Ancillary immobilization devices contribute to overall attenuation of the PET signal, but are not detected with conventional MR sequences and, hence, are ignored in standard MR-based attenuation correction (MR-AC). We report on the quantitative effect of not accounting for the attenuation of patient positioning aids in combined PET/MR imaging. We used phantom and patient data acquired with positioning aids on a PET/CT scanner (Biograph 16, HI-REZ) to mimic PET/MR imaging conditions. Reference CT-based attenuation maps were generated from measured (original) CT transmission images (origCT-AC). We also created MR-like attenuation maps by following the same conversion procedure of the attenuation values except for the prior delineation and subtraction of the positioning aids from the CT images (modCT-AC). First, a uniform {sup 68}Ge cylinder was positioned centrally in the PET/CT scanner and fixed with a vacuum mattress (10 cm thick) and, in a repeat examination, with MR positioning foam pads. Second, 16 patient datasets were selected for subsequent processing. All patients were regionally immobilized with positioning aids: a vacuum mattress for head/neck imaging (nine patients) and a foam mattress for imaging of the lower extremities (seven patients). PET images were reconstructed following CT-based attenuation and scatter correction using the original and modified (MR-like) CT images: PET{sub origCT-AC} and PET{sub modCT-AC}, respectively. PET images following origCT-AC and modCT-AC were compared visually and in terms of mean differences of voxels with a standardized uptake value of at least 1.0. In addition, we report maximum activity concentration in lesions for selected patients. In the phantom study employing the vacuum mattress the average voxel activity in PET{sub modCT-AC} was underestimated by 6.4% compared to PET

  15. The effect of patient positioning aids on PET quantification in PET/MR imaging.

    Science.gov (United States)

    Mantlik, Frederic; Hofmann, Matthias; Werner, Matthias K; Sauter, Alexander; Kupferschläger, Jürgen; Schölkopf, Bernhard; Pichler, Bernd J; Beyer, Thomas

    2011-05-01

    Clinical PET/MR requires the use of patient positioning aids to immobilize and support patients for the duration of the combined examination. Ancillary immobilization devices contribute to overall attenuation of the PET signal, but are not detected with conventional MR sequences and, hence, are ignored in standard MR-based attenuation correction (MR-AC). We report on the quantitative effect of not accounting for the attenuation of patient positioning aids in combined PET/MR imaging. We used phantom and patient data acquired with positioning aids on a PET/CT scanner (Biograph 16, HI-REZ) to mimic PET/MR imaging conditions. Reference CT-based attenuation maps were generated from measured (original) CT transmission images (origCT-AC). We also created MR-like attenuation maps by following the same conversion procedure of the attenuation values except for the prior delineation and subtraction of the positioning aids from the CT images (modCT-AC). First, a uniform (68)Ge cylinder was positioned centrally in the PET/CT scanner and fixed with a vacuum mattress (10 cm thick) and, in a repeat examination, with MR positioning foam pads. Second, 16 patient datasets were selected for subsequent processing. All patients were regionally immobilized with positioning aids: a vacuum mattress for head/neck imaging (nine patients) and a foam mattress for imaging of the lower extremities (seven patients). PET images were reconstructed following CT-based attenuation and scatter correction using the original and modified (MR-like) CT images: PET(origCT-AC) and PET(modCT-AC), respectively. PET images following origCT-AC and modCT-AC were compared visually and in terms of mean differences of voxels with a standardized uptake value of at least 1.0. In addition, we report maximum activity concentration in lesions for selected patients. In the phantom study employing the vacuum mattress the average voxel activity in PET(modCT-AC) was underestimated by 6.4% compared to PET(origCT-AC), with 3

  16. FDG PET/CT in cancer

    DEFF Research Database (Denmark)

    Petersen, Henrik; Holdgaard, Paw Christian; Madsen, Poul Henning

    2016-01-01

    -recommendable" indications, respectively. RESULTS: Of 11,729 citations, 1,729 were considered for review, and 204 were included. The evidence suggested usefulness of PET/CT in lung, lymphoma, melanoma, head and neck, and colorectal cancers, whereas evidence was sparse in gynaecological cancers. The agreement between actual...... use of PET/CT and literature-based recommendations was high in the first five mentioned cancers in that 96.2 % of scans were made for grade A or B indications versus only 22.2 % in gynaecological cancers. CONCLUSION: Evidence-based usefulness was reported in five of six selected cancers; evidence...

  17. The Role of 18F-FDG PET/CT and PET/MRI in Pancreatic Ductal Adenocarcinoma.

    Science.gov (United States)

    Yeh, Randy; Dercle, Laurent; Garg, Ishan; Wang, Zhen Jane; Hough, David M; Goenka, Ajit H

    2017-11-16

    Pancreatic ductal adenocarcinoma (PDAC) remains a difficult disease to treat and continues to portend a poor prognosis, as most patients are unresectable at diagnosis. 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET) combined with CT (PET/CT) has been a cornerstone in oncological imaging of different cancers; however, the role of PET/CT in PDAC is continually evolving and currently not well established. Studies have shown the potential of PET/CT in guiding the management of patients with PDAC, with possible added benefit over anatomic imaging with CT or MRI in certain scenarios. PET/CT may be useful in diagnosis, initial staging, treatment response assessment, differentiation of recurrent tumor from post-treatment fibrosis, and radiotherapy planning. Additionally, PET/CT may be a cost-effective modality due to upstaging of patients originally deemed as surgical candidates. Recently, the advent of simultaneous PET/MRI represents an exciting advancement in hybrid functional imaging with potential applications in the imaging of PDAC. The advantages of PET/MRI include simultaneous acquisition to improve registration of fusion images, lower radiation dose, superior soft tissue contrast, and availability of multiparametric imaging. Studies are underway to evaluate the utility of PET/MRI in PDAC, including in initial staging and treatment response assessment and to determine the subgroup of patients that will benefit from PET/MRI. Further studies are warranted in both PET/CR and PET/MRI to better understand the role of these modalities in PDAC.

  18. Similarities between obesity in pets and children: the addiction model.

    Science.gov (United States)

    Pretlow, Robert A; Corbee, Ronald J

    2016-09-01

    Obesity in pets is a frustrating, major health problem. Obesity in human children is similar. Prevailing theories accounting for the rising obesity rates - for example, poor nutrition and sedentary activity - are being challenged. Obesity interventions in both pets and children have produced modest short-term but poor long-term results. New strategies are needed. A novel theory posits that obesity in pets and children is due to 'treats' and excessive meal amounts given by the 'pet-parent' and child-parent to obtain affection from the pet/child, which enables 'eating addiction' in the pet/child and results in parental 'co-dependence'. Pet-parents and child-parents may even become hostage to the treats/food to avoid the ire of the pet/child. Eating addiction in the pet/child also may be brought about by emotional factors such as stress, independent of parental co-dependence. An applicable treatment for child obesity has been trialled using classic addiction withdrawal/abstinence techniques, as well as behavioural addiction methods, with significant results. Both the child and the parent progress through withdrawal from specific 'problem foods', next from snacking (non-specific foods) and finally from excessive portions at meals (gradual reductions). This approach should adapt well for pets and pet-parents. Pet obesity is more 'pure' than child obesity, in that contributing factors and treatment points are essentially under the control of the pet-parent. Pet obesity might thus serve as an ideal test bed for the treatment and prevention of child obesity, with focus primarily on parental behaviours. Sharing information between the fields of pet and child obesity would be mutually beneficial.

  19. PET/MRI and PET/CT in follow-up of head and neck cancer patients

    Energy Technology Data Exchange (ETDEWEB)

    Queiroz, Marcelo A. [University Hospital Zurich, Department of Medical Radiology, Nuclear Medicine, Zurich (Switzerland); University Hospital Zurich, Department of Nuclear Medicine, Zurich (Switzerland); Huellner, Martin [University Hospital Zurich, Department of Medical Radiology, Nuclear Medicine, Zurich (Switzerland); University Hospital Zurich, Department of Medical Radiology, Neuroradiology, Zurich (Switzerland); Kuhn, Felix; Veit-Haibach, Patrick [University Hospital Zurich, Department of Medical Radiology, Nuclear Medicine, Zurich (Switzerland); University Hospital Zurich, Department of Medical Radiology, Diagnostic and Interventional Radiology, Zurich (Switzerland); Huber, Gerhardt; Meerwein, Christian [University Hospital Zurich, Department of Otorhinolaryngology, Zurich (Switzerland); Kollias, Spyros [University Hospital Zurich, Department of Medical Radiology, Neuroradiology, Zurich (Switzerland); Schulthess, Gustav von [University Hospital Zurich, Department of Medical Radiology, Nuclear Medicine, Zurich (Switzerland)

    2014-06-15

    Positron emission tomography (PET)/MRI combines the functional ability of PET and the high soft tissue contrast of MRI. The aim of this study was to assess contrast-enhanced (ce)PET/MRI compared to cePET/CT in patients with suspected recurrence of head and neck cancer (HNC). Eighty-seven patients underwent sequential cePET/CT and cePET/MRI using a trimodality PET/CT-MRI set-up. Diagnostic accuracy for the detection of recurrent HNC was evaluated using cePET/CT and cePET/MRI. Furthermore, image quality, presence of unclear {sup 18}F-fluorodeoxy-D-glucose (FDG) findings of uncertain significance and the diagnostic advantages of use of gadolinium contrast enhancement were analysed. cePET/MRI showed no statistically significant difference in diagnostic accuracy compared to cePET/CT (91.5 vs 90.6 %). Artefacts' grade was similar in both methods, but their location was different. cePET/CT artefacts were primarily located in the suprahyoid area, while on cePET/MRI, artefacts were more equally distributed among the supra and infrahyoid neck regions. cePET/MRI and cePET/CT showed 34 unclear FDG findings; of those 11 could be solved by cePET/MRI and 5 by cePET/CT. The use of gadolinium in PET/MRI did not yield higher diagnostic accuracy, but helped to better define tumour margins in 6.9 % of patients. Our data suggest that cePET/MRI may be superior compared to cePET/CT to specify unclear FDG uptake related to possible tumour recurrence in follow-up of patients after HNC. It seems to be the modality of choice for the evaluation of the oropharynx and the oral cavity because of a higher incidence of artefacts in cePET/CT in this area mainly due to dental implants. However, overall there is no statistically significant difference. (orig.)

  20. Oral cancer diagnosed using PET/CT: A case report

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Young Hee; Yang, Byoung Eun; Cho, Young Min [Hallym Univ. College of Medicine, Anyang (Korea, Republic of); Kim, Seong Gon [Sam Anyang General Hospital, Anyang (Korea, Republic of)

    2006-06-15

    PET/CT is a new imaging technology that combines high-quality Position Emission Tomography (PET) and Computed Tomography (CT). This imaging provides simultaneous anatomical and metabolic information. Therefore PET/CT is useful diagnostic modality for early detection og malignant tumor, accurate at aging, decision on therapeutic plan, monitoring response to therapy and rapid detection of recurrence. We report oral and maxillofacial cancers diagnosed by using PET/CT and the usefulness of PET/CT in the evaluation of postoperative recurrence.

  1. Potential benefits of pet ownership in health promotion.

    Science.gov (United States)

    Jennings, L B

    1997-12-01

    Pet ownership provides an opportunity to improve health. A pet may become a stimulus for exercise, reduce anxiety, and provide an external focus of attention. Pets are also a source of physical contact and comfort and may decrease loneliness and depression while promoting an interesting lifestyle. The benefits of pet ownership are consistent with the health promotion and disease prevention goals outlined in Healthy People 2000. These goals include (a) increasing physical activity and fitness and (b) improving mental health and preventing mental disorders. Assessment of pet ownership and discussion of potential health benefits facilitates a holistic understanding of our patients and ourselves.

  2. [¹⁸F]-fluorodeoxyglucose PET imaging of atherosclerosis

    DEFF Research Database (Denmark)

    Blomberg, Björn Alexander; Høilund-Carlsen, Poul Flemming

    2015-01-01

    [(18)F]-fluorodeoxyglucose PET ((18)FDG PET) imaging has emerged as a promising tool for assessment of atherosclerosis. By targeting atherosclerotic plaque glycolysis, a marker for plaque inflammation and hypoxia, (18)FDG PET can assess plaque vulnerability and potentially predict risk...... of atherosclerosis-related disease, such as stroke and myocardial infarction. With excellent reproducibility, (18)FDG PET can be a surrogate end point in clinical drug trials, improving trial efficiency. This article summarizes key findings in the literature, discusses limitations of (18)FDG PET imaging...

  3. Validating PET segmentation of thoracic lesions-is 4D PET necessary?

    DEFF Research Database (Denmark)

    Nielsen, M. S.; Carl, J.

    2017-01-01

    segmented using three SUV threshold methods (Max40%, SUV40% and 2.5SUV) and a gradient based method (GradientSeg). Segmentations in static 3D-PET scans (PETsta) specified the reference conditions for the individual segmentation methods, target lesions and tracer concentrations. The motion included PET......Uptake(error)) for the lesion part covering the low tracer concentration. In PET4D images, all segmentation methods provided lowUptakeerror estimates equivalent to PETsta segmentations and, except for the Max40% segmentations, a slight volume expansion. In the PET(mo)t images, the GradientSeg method results in an average 0.......43 increased volume and an overestimation of 0.33 for the lowUptakeerror. The most accurate segmentations in PETmot, relative to PETsta, were accomplished by the 2.5SUV and SUV40% methods. In the PETdeb images, the GradientSeg method solitary provided segmentations equivalent to segmentation in PETsta images...

  4. PET and paediatrics; La tomographie par emission de positons (ou PET scan) en pediatrie

    Energy Technology Data Exchange (ETDEWEB)

    Boddaert, N. [Necker Enfants Malades, AP-HP, Serv Radiol Pediat, Paris (France); Ribeiro, M.J. [CEA, DSV, I2BM, Serv Hosp Frederic Joliot, F-91406 Orsay (France)

    2008-07-01

    Positon emission tomography (PET scan) is a functional imagery technique.As in scintigraphy, a radioactive tracer is administrated to the patient and its distribution into the organism is detected by a tomograph or a PET scanner. The nuclear medicine techniques which use radioactive tracers allow to obtain an imagery of the regional metabolism of glucose, blood flow or of different neurotransmitters. The PET-TDM (tomodensitometry) is an hybrid imagery system which associates a PET to a multi-bars scanner (4 to 64 bars). The use of hybrid imagery systems allows an anatomic register of the metabolic anomalies or others, as well as the adjustment of the attenuation of the emitted particles. (O.M.)

  5. The Maillard reaction and pet food processing: effects on nutritive value and pet health

    National Research Council Canada - National Science Library

    Rooijen, van, C; Bosch, G; Poel, van der, A.F.B; Wierenga, P.A; Alexander, L; Heniks, W.H

    2013-01-01

    The Maillard reaction, which can occur during heat processing of pet foods or ingredients, is known to reduce the bioavailability of essential amino acids such as lysine due to the formation of early...

  6. Development of a full-ring ;add-on PET; prototype: A head coil with DOI-PET detectors for integrated PET/MRI

    Science.gov (United States)

    Nishikido, F.; Fujiwara, M.; Tashima, H.; Akram, M. S. H.; Suga, M.; Obata, T.; Yamaya, T.

    2017-08-01

    We developed a full-ring ;add-on PET; prototype which is brain-dedicated and consists of a RF-head coil with four-layer depth-of-interaction (DOI) PET detectors for integrated PET/MRI in order to evaluate performance of our previously proposed add-on PET system and to investigate the mutual influences between the individual PET and MRI modalities when they are integrated in simultaneous measurements. In this add-on PET prototype, the DOI detectors are mounted on the head coil and close to the patient head. As a result, higher sensitivity and higher spatial resolution can be achieved for the integrated PET/MRI, compared with conventional whole body PET/MRI systems. In addition, implementation cost can be reduced, tuning of the RF-coil can be optimized and PET and MRI images can be obtained simultaneously in exactly the same positions. Specifically, the full-ring prototype consists of eight DOI-PET detectors and a birdcage type head coil of a 3T MRI. The radius of the PET ring is 123.9 mm. The distance from the center to the RF-coil elements is 130.5 mm. The scintillator blocks consist of lutetium-yttrium oxyorthosilicate scintillators arranged in 19×6×4 layers with reflectors inserted between them. The size of each crystal element is 2.0 mm×2.0 mm ×5.0 mm. We evaluated performance of the full-ring prototype in simultaneous measurements of the integrated PET/MRI. We obtained spatial resolutions of 2.3 mm at the center of the field-of-view (FOV) and lower than 3.5 mm in the whole FOV. The energy resolution of 19.4% was obtained for 511 keV gamma-rays. In addition, we observed no degradation of PET performance caused by the MRI measurement. The signal-to-noise ratio (SNR) of the MRI image was 209.4 in simultaneous measurements with the PET. The maximum ΔB0 and maximum difference of the secondary magnetic field due to the eddy current effect were smaller than 0.8 ppm and ±5.0 μT, respectively. We concluded that sufficient spatial resolution and detector

  7. Feasibility of simultaneous PET/MR of the carotid artery: first clinical experience and comparison to PET/CT

    Science.gov (United States)

    Ripa, Rasmus S; Knudsen, Andreas; Hag, Anne Mette F; Lebech, Anne-Mette; Loft, Annika; Keller, Sune H; Hansen, Adam E; von Benzon, Eric; Højgaard, Liselotte; Kjær, Andreas

    2013-01-01

    The study aimed at comparing PET/MR to PET/CT for imaging the carotid arteries in patients with known increased risk of atherosclerosis. Six HIV-positive men underwent sequential PET/MR and PET/CT of the carotid arteries after injection of 400 MBq of 18F-FDG. PET/MR was performed a median of 131 min after injection. Subsequently,PET/CT was performed. Regions of interest (ROI) were drawn slice by slice to include the carotid arteries and standardized uptake values (SUV) were calculated from both datasets independently. Quantitative comparison of 18F-FDG uptake revealed a high congruence between PET data acquired using the PET/MR system compared to the PET/CT system. The mean difference for SUVmean was -0.18 (p PET/MR system. The 95% limits of agreement were -0.55 to 0.20 for SUVmean and -0.93 to 0.65 for SUVmax. The image quality of the PET/MR allowed for delineation of the carotid vessel wall. The correlations between 18F-FDG uptake from ROI including both vessel wall and vessel lumen to ROI including only the wall were strong (r = 0.98 for SUVmean and r = 1.00 for SUVmax) indicating that the luminal 18F-FDG content had minimal influence on the values. The study shows for the first time that simultaneous PET/MR of the carotid arteries is feasible in patients with increased risk of atherosclerosis. Quantification of 18F-FDG uptake correlated well between PET/MR and PET/CT despite difference in method of PET attenuation correction, reconstruction algorithm, and detector technology. PMID:23900769

  8. Supplemental transmission method for improved PET attenuation correction on an integrated MR/PET

    Energy Technology Data Exchange (ETDEWEB)

    Watson, Charles C., E-mail: charles.c.watson@siemens.com

    2014-01-11

    Although MR image segmentation, combined with information from the PET emission data, has achieved a clinically usable PET attenuation correction (AC) on whole-body MR/PET systems, more accurate PET AC remains one of the main instrumental challenges for quantitative imaging. Incorporating a full conventional PET transmission system in these machines would be difficult, but even a small amount of transmission data might usefully complement the MR-based estimate of the PET attenuation image. In this paper we explore one possible configuration for such a system that uses a small number of fixed line sources placed around the periphery of the patient tunnel. These line sources are implemented using targeted positron beams. The sparse transmission (sTX) data are collected simultaneously with the emission (EM) acquisition. These data, plus a blank scan, are combined with a partially known attenuation image estimate in a modified version of the maximum likelihood for attenuation and activity (MLAA) algorithm, to estimate values of the linear attenuation coefficients (LAC) in unknown regions of the image. This algorithm was tested in two simple phantom experiments. We find that the use of supplemental transmission data can significantly improve the accuracy of the estimated LAC in a truncated region, as well as the estimate of the emitter concentration within the phantom. In the experiments, the bias in the EM+sTX estimate of emitter concentrations was 3–5%, compared to 15–20% with the use of EM-only data. Highlights: • MR-based PET attenuation correction (AC) on MR/PET scanners remains problematic. • We propose a supplemental sparse transmission (sTX) system to improve MR-AC. • The sTX sources were implemented very practically using targeted positron beams. • A novel MLAA-like algorithm was developed to reconstruct these data. • We show that sTX leads to more accurate emission images in two phantom studies.

  9. Assessment of attenuation correction for myocardial PET imaging using combined PET/MRI.

    Science.gov (United States)

    Lassen, Martin Lyngby; Rasul, Sazan; Beitzke, Dietrich; Stelzmüller, Marie-Elisabeth; Cal-Gonzalez, Jacobo; Hacker, Marcus; Beyer, Thomas

    2017-11-22

    To evaluate the frequency of artifacts in MR-based attenuation correction (AC) maps and their impact on the quantitative accuracy of PET-based flow and metabolism measurements in a cohort of consecutive heart failure patients undergoing combined PET/MR imaging. Myocardial viability studies were performed in 20 patients following a dual-tracer protocol involving the assessment of myocardial perfusion (13N-NH3: 813 ± 86 MBq) and metabolism (18F-FDG: 335 ± 38 MBq). All acquisitions were performed using a fully-integrated PET/MR system, with standard DIXON-attenuation correction (DIXON-AC) mapping for each PET scan. All AC maps were examined for spatial misalignment with the emission data, total lung volume, susceptibility artifacts, and tissue inversion (TI). Misalignment and susceptibility artifacts were corrected using rigid co-registration and retrospective filling of the susceptibility-induced gaps, respectively. The effects of the AC artifacts were evaluated by relative difference measures and perceived changes in clinical interpretations. Average respiratory misalignment of (7 ± 4) mm of the PET-emission data and the AC maps was observed in 18 (90%) patients. Substantial changes in the lung volumes of the AC maps were observed in the test-retest analysis (ratio: 1.0 ± 0.2, range: 0.8-1.4). Susceptibility artifacts were observed in 10 (50%) patients, while six (30%) patients had TI artifacts. Average differences of 14 ± 10% were observed for PET images reconstructed with the artifactual AC maps. The combined artifact effects caused false-positive findings in three (15%) patients. Standard DIXON-AC maps must be examined carefully for artifacts and misalignment effects prior to AC correction of cardiac PET/MRI studies in order to avoid misinterpretation of biased perfusion and metabolism readings from the PET data.

  10. Pet ownership and risk factors for cardiovascular disease: another look.

    Science.gov (United States)

    Parslow, Ruth A; Jorm, Anthony F

    2003-11-03

    To test the claim that pet ownership reduces cardiovascular risk. Community survey. 2528 adults aged 40-44 years and 2551 aged 60-64 years who lived in the Australian Capital Territory and Queanbeyan, New South Wales, and were drawn randomly from the Australian electoral roll in 2000 and 2001. Sociodemographic measures, including pet ownership, and measures of physical health (including body mass index [BMI], alcohol and cigarette consumption, and levels of physical activity). Two readings of diastolic and systolic blood pressure were also taken. While pet owners and non-pet owners had similar levels of systolic blood pressure, those with pets had significantly higher diastolic blood pressure. Pet owners also had higher BMI and were more likely to smoke. While those with pets undertook more mild physical activity, they continued to have significantly higher diastolic blood pressure after controlling for hypertensive risk factors. In this study, we found no evidence that pet ownership per se is associated with cardiovascular health benefits. Rather, pet owners had higher diastolic blood pressure than those without pets. It is likely that this increased health risk is linked to other hypertensive risk factors that are only indirectly associated with pet ownership.

  11. Factors associated with furry pet ownership among patients with asthma.

    Science.gov (United States)

    Downes, Martin J; Roy, Angkana; McGinn, Thomas G; Wisnivesky, Juan P

    2010-09-01

    Exposure to indoor allergens is an established risk factor for poor asthma control. Current guidelines recommend removing pets from the home of patients with asthma. This cross-sectional study was conducted to determine the prevalence of furry pet ownership in asthmatics compared to non-asthmatics and to identify factors associated with furry pet ownership among those with asthma. Secondary analysis assessed characteristics among asthmatics that might be associated with allowing a furry pet into the bedroom. Using data from The National Asthma Survey collected from 2003 to 2004, we carried out univariate and multiple regression analyses, in 2009, to identify independent predictors of furry pet ownership in asthma sufferers after controlling for potential confounders. Overall, asthmatics were more likely to own a furry pet than nonasthmatic individuals in the general population (49.9% versus 44.8%, p pet ownership among asthmatics. Additionally, 68.7% of patients with asthma who own a furry pet allowed them into their bedroom. Higher income and carrying out pet into the bedroom. Furry pet ownership is equally or more common among asthmatics compared to those without asthma. The majority of asthmatics with furry pets allow them into the bedroom. Recognizing and addressing these problems may help decrease asthma morbidity.

  12. FDG-PET/CT in oncology. German guideline

    Energy Technology Data Exchange (ETDEWEB)

    Krause, B.J. [Nuklearmedizinische Klinik und Poliklinik, Technische Univ. Muenchen (Germany); Beyer, T.; Bockisch, A. [Klinik fuer Nuklearmedizin, Universitaetsklinikum Essen (Germany); Delbeke, D. [Vanderbilt Univ. Medical Center, Nashville, TN (United States); Kotzerke, J. [Klinik und Poliklinik fuer Nuklearmedizin, Universitaetsklinikum Dresden (Germany); Minkov, V. [Bundesamt fuer Strahlenschutz, Salzgitter (Germany); Reiser, M. [Inst. fuer Klinische Radiologie, Ludwig-Maximillians-Univ. Muenchen (Germany); Willich, N. [Klinik und Poliklinik fuer Strahlentherapie - Radioonkologie, Universitaetsklinikum Muenster (Germany)

    2007-07-01

    FDG-PET/CT examinations combine metabolic and morphologic imaging within an integrated procedure. Over the past decade PET/CT imaging has gained wide clinical acceptance in the field of oncology. This FDG-PET/CT guideline focuses on indications, data acquisition and processing as well as documentation of FDG-PET/CT examinations in oncologic patients within a clinical and social context specific to Germany. Background information and definitions are followed by examples of clinical and research applications of FDG-PET/CT. Furthermore, protocols for CT scanning (low dose and contrast-enhanced CT) and PET emission imaging are discussed. Documentation and reporting of examinations are specified. Image interpretation criteria and sources of errors are discussed. Quality control for FDG and PET/CT-systems, qualification requirements of personnel as well as legal aspects are presented. (orig.)

  13. Optimization of yttrium-90 PET for simultaneous PET/MR imaging: A phantom study.

    Science.gov (United States)

    Eldib, Mootaz; Oesingmann, Niels; Faul, David D; Kostakoglu, Lale; Knešaurek, Karin; Fayad, Zahi A

    2016-08-01

    Positron emission tomography (PET) imaging of yttrium-90 in the liver post radioembolization has been shown useful for personalized dosimetry calculations and evaluation of extrahepatic deposition. The purpose of this study was to quantify the benefits of several MR-based data correction approaches offered by using a combined PET/MR system to improve Y-90 PET imaging. In particular, the feasibility of motion and partial volume corrections were investigated in a controlled phantom study. The ACR phantom was filled with an initial concentration of 8 GBq of Y-90 solution resulting in a contrast of 10:1 between the hot cylinders and the background. Y-90 PET motion correction through motion estimates from MR navigators was evaluated by using a custom-built motion stage that simulated realistic amplitudes of respiration-induced liver motion. Finally, the feasibility of an MR-based partial volume correction method was evaluated using a wavelet decomposition approach. Motion resulted in a large (∼40%) loss of contrast recovery for the 8 mm cylinder in the phantom, but was corrected for after MR-based motion correction was applied. Partial volume correction improved contrast recovery by 13% for the 8 mm cylinder. MR-based data correction improves Y-90 PET imaging on simultaneous PET/MR systems. Assessment of these methods must be studied further in the clinical setting.

  14. Cardiovascular hybrid imaging using PET/MRI; Kardiovaskulaere Hybridbildgebung mit PET/MRT

    Energy Technology Data Exchange (ETDEWEB)

    Nensa, Felix; Schlosser, Thomas [Universitaetsklinikum Essen (Germany). Inst. fuer Diagnostische und Interventionelle Radiologie und Neuroradiologie

    2014-12-15

    The following overview provides a summary of the state of the art and research as well as potential clinical applications of cardiovascular PET/MR imaging. PET/MRI systems have been clinically available for a few years, and their use in cardiac imaging has been successfully demonstrated. At this period in time, some of the technical difficulties that arose at the beginning have been solved; in particular with respect to MRI-based attenuation correction, caution should be exercised with PET quantification. In addition, many promising technical options are still in the developmental stage, such as MRI-based motion correction of PET data resulting from simultaneous MR acquisition, and are not yet available for cardiovascular imaging. On the other hand, PET/MRI has been used to demonstrate significant pathologies such as acute and chronic myocardial infarction, myocarditis or cardiac sarcoidosis; future applications in clinical routine or within studies appear to be possible. In coming years additional studies will have to be performed to prove diagnostic gain at a reasonable cost-benefit ratio before valid conclusions are possible regarding the clinical utility and future of cardiovascular PET/MR imaging.

  15. Anthropogenic and Naturally Produced Brominated Phenols in Pet Blood and Pet Food in Japan.

    Science.gov (United States)

    Mizukawa, Hazuki; Nomiyama, Kei; Nakatsu, Susumu; Yamamoto, Miyuki; Ishizuka, Mayumi; Ikenaka, Yoshinori; Nakayama, Shouta M M; Tanabe, Shinsuke

    2017-10-03

    Present study determined concentrations and residue patterns of bromophenols (BPhs) in whole blood samples of pet cats and pet dogs collected from veterinary hospitals in Japan. BPhs concentrations were higher in cat blood than in dog blood, with statistically insignificant differences (p = 0.07). Among the congeners, 2,4,6-tribromophenol (TBPh) constituted the majority of BPhs (>90%) detected in both species. Analysis of commercial pet food to estimate exposure routes showed that the most abundant congener in all pet food samples was 2,4,6-TBPh, accounting for >99% of total BPhs. This profile is quite similar to the blood samples of the pets, suggesting that diet might be an important exposure route for BPhs in pets. After incubation in polybrominated diphenyl ether (PBDE) mixtures (BDE-47, BDE-99 and BDE-209), 2,4,5-TBPh was found in dog liver microsomes but not in cat liver microsomes, implying species-specific metabolic capacities for PBDEs. Formation of 2,4,5-TBPh occurred by hydroxylation at the 1' carbon atom of the ether bond of BDE-99 is similar to human study reported previously. Hydroxylated PBDEs were not detected in cats or dogs; therefore, diphenyl ether bond cleavage of PBDEs can also be an important metabolic pathway for BPhs formation in cats and dogs.

  16. Importance of PET/CT for imaging of colorectal cancer; Stellenwert der PET/CT zur Bildgebung des kolorektalen Karzinoms

    Energy Technology Data Exchange (ETDEWEB)

    Meinel, F.G.; Schramm, N.; Graser, A.; Reiser, M.F.; Rist, C. [Klinikum der Ludwig-Maximilians-Universitaet Muenchen, Campus Grosshadern, Institut fuer Klinische Radiologie, Muenchen (Germany); Haug, A.R. [Klinikum der Ludwig-Maximilians-Universitaet Muenchen, Campus Grosshadern, Klinik und Poliklinik fuer Nuklearmedizin, Muenchen (Germany)

    2012-06-15

    Fluorodeoxyglucose-positron emission tomography/computed tomography (FDG-PET/CT) has emerged as a very useful imaging modality in the management of colorectal carcinoma. Data from the literature regarding the role of PET/CT in the initial diagnosis, staging, radiotherapy planning, response monitoring and surveillance of colorectal carcinoma is presented. Future directions and economic aspects are discussed. Computed tomography (CT), magnetic resonance imaging (MRI) and FDG-PET for colorectal cancer and endorectal ultrasound for rectal cancer. Combined FDG-PET/CT. While other imaging modalities allow superior visualization of the extent and invasion depth of the primary tumor, PET/CT is most sensitive for the detection of distant metastases of colorectal cancer. We recommend a targeted use of PET/CT in cases of unclear M staging, prior to metastasectomy and in suspected cases of residual or recurrent colorectal carcinoma with equivocal conventional imaging. The role of PET/CT in radiotherapy planning and response monitoring needs to be determined. Currently there is no evidence to support the routine use of PET/CT for colorectal screening, staging or surveillance. To optimally exploit the synergy between morphologic and functional information, FDG-PET should generally be performed as an integrated FDG-PET/CT with a contrast-enhanced CT component in colorectal carcinoma. (orig.) [German] Die Fluordesoxyglukose-Positronenemissionstomographie/Computertomographie (FDG-PET/CT) hat in den letzten Jahren zunehmende Bedeutung zur Bildgebung des kolorektalen Karzinoms erlangt. In diesem Beitrag stellen wir den Stand der Literatur zur Rolle der PET/CT bei Screening, Staging, Bestrahlungsplanung, Beurteilung eines Therapieansprechens und Nachsorge des kolorektalen Karzinoms dar. Zudem wird auf gesundheitsoekonomische Aspekte und zukuenftige Entwicklungen eingegangen. CT, MRT, FDG-PET, beim Rektumkarzinom zusaetzlich endorektaler Ultraschall. Kombinierte FDG-PET/CT. Waehrend

  17. PET/MR Imaging in Musculoskeletal Disorders

    DEFF Research Database (Denmark)

    Andersen, Kim Francis; Jensen, Karl Erik; Loft, Annika

    2016-01-01

    , treatment planning and monitoring, and follow-up of patients with musculoskeletal malignancies, and may also prove helpful in assessment of musculoskeletal infectious and inflammatory disorders. The application of more sophisticated MR imaging sequences and PET radiotracers other than FDG in the diagnostic...... workup and follow-up of patients with musculoskeletal disorders should be explored....

  18. SPECT and PET in Eating Disorders

    NARCIS (Netherlands)

    van Waarde, Aren; Audenaert, Kurt; Busatto, Geraldo F.; Buchpiguel, Carlos; Dierckx, Rudi; Dierckx, Rudi AJO; Otte, Andreas; de Vries, Erik FJ; van Waarde, Aren; den Boer, Johan A

    2014-01-01

    Medical imaging techniques like PET and SPECT have been applied for investigation of brain function in anorexia and bulimia nervosa. Regional abnormalities have been detected in cerebral blood flow, glucose metabolism, the availability of several neurotransmitter receptors (serotonin 1A and 2A,

  19. Status of CIEMAT work on PETS

    Science.gov (United States)

    Toral, F.; Abramian, P.; Aragón, F.; Calero, J.; Carrillo, D.; Gutiérrez, J. L.; Lara, A.; Rodríguez, E.; Sánchez, L.; Doebert, S.; Mathot, S.; Riddone, G.; Samoshkin, A.; Syratchev, I.

    2011-11-01

    The goal of the present CLIC Test Facility (CTF3) is to demonstrate the technical feasibility of the CLIC scheme, where the RF power extracted from the drive beam is used to accelerate the main beam. Several prototypes of the RF power extractor so-called PETS (Power Extraction and Transfer Structure) have been developed at CIEMAT for this facility. The first device was embedded in a steel vacuum tank and installed at the Test Beam Line (TBL), whose aim is to prove the beam stability during deceleration and power extraction. Presently, CERN and CIEMAT share the responsibility to build eight additional PETS for TBL. Finally, in the framework of EuCARD (European Coordination for Accelerator Research and Development) collaboration, a new PETS configuration is presently under engineering design at CIEMAT. It is based on a compact concept developed at CERN. This device will be installed in the Test Module at CTF3, in a similar configuration to that of the final two-beam scheme acceleration of CLIC. This paper describes the PETS prototype fabrication techniques used at CIEMAT, with particular attention to the production of the long copper rods which induce the RF generation and the welding and assembly procedures. The characterization of the devices with low RF power and the first tests with beam are also described.

  20. Pet Responsibility: Citizenship Lessons for Elementary Students.

    Science.gov (United States)

    Fitzgerald, Thomas A.

    This unit is designed around a four-week plan integrated into third- and fourth-grade science, social studies, language arts, reading, and art. The unit takes students through specific strategies of creating awareness about issues and to help them become more responsible about pet care, personally and in the community. Each week has a theme,…

  1. Status of CIEMAT work on PETS

    Energy Technology Data Exchange (ETDEWEB)

    Toral, F., E-mail: fernando.toral@ciemat.es [Centro de Investigaciones Energeticas, Medioambientales y Tecnologicas (CIEMAT), Avda. Complutense 22, 28040 Madrid (Spain); Abramian, P.; Aragon, F.; Calero, J.; Carrillo, D.; Gutierrez, J.L.; Lara, A.; Rodriguez, E.; Sanchez, L. [Centro de Investigaciones Energeticas, Medioambientales y Tecnologicas (CIEMAT), Avda. Complutense 22, 28040 Madrid (Spain); Doebert, S.; Mathot, S.; Riddone, G.; Samoshkin, A.; Syratchev, I. [European Organization for Nuclear Research (CERN), CH-1211, Geneva 23 (Switzerland)

    2011-11-21

    The goal of the present CLIC Test Facility (CTF3) is to demonstrate the technical feasibility of the CLIC scheme, where the RF power extracted from the drive beam is used to accelerate the main beam. Several prototypes of the RF power extractor so-called PETS (Power Extraction and Transfer Structure) have been developed at CIEMAT for this facility. The first device was embedded in a steel vacuum tank and installed at the Test Beam Line (TBL), whose aim is to prove the beam stability during deceleration and power extraction. Presently, CERN and CIEMAT share the responsibility to build eight additional PETS for TBL. Finally, in the framework of EuCARD (European Coordination for Accelerator Research and Development) collaboration, a new PETS configuration is presently under engineering design at CIEMAT. It is based on a compact concept developed at CERN. This device will be installed in the Test Module at CTF3, in a similar configuration to that of the final two-beam scheme acceleration of CLIC. This paper describes the PETS prototype fabrication techniques used at CIEMAT, with particular attention to the production of the long copper rods which induce the RF generation and the welding and assembly procedures. The characterization of the devices with low RF power and the first tests with beam are also described.

  2. The Value of Pets in Children's Lives

    Science.gov (United States)

    Blue, Gladys F.

    1986-01-01

    Reviews literature focusing on six aspects of pet-person relationships that are most relevant to the growing child. Areas include love, attachment, and comfort; sensorimotor and nonverbal learning; responsibility, nurturance, and competence; learning about the life cycle; therapeutic benefits; and nurturing humaness, ecological awareness, and…

  3. Thin Time-Of-Flight PET project

    CERN Multimedia

    The pre-R&D aims at designing and producing a compact and thin Time-Of-Flight PET detector device with depth of interaction measurement capability, which employs layered silicon sensors as active material, with a readout consisting of a new generation of very-low noise and very fast electronics based on SiGe Heterojunction Bipolar Transistors (HBT) components.

  4. PET/CT in Radiation Therapy Planning

    DEFF Research Database (Denmark)

    Specht, Lena; Berthelsen, Anne Kiil

    2018-01-01

    Radiation therapy (RT) is an important component of the management of lymphoma patients. Most lymphomas are metabolically active and accumulate 18F-fluorodeoxyglucose (FDG). Positron emission tomography with computer tomography (PET/CT) imaging using FDG is used routinely in staging and treatment...

  5. OCCURENCE OF MERCURY IN PET FOOD

    Directory of Open Access Journals (Sweden)

    M.C. Abete

    2013-02-01

    Full Text Available Mercury levels in 61 complete pet feed containing fish were evaluated. In five samples a mercury content exceeding the maximum residues level (0.4 mg/kg was detected. The statistical evaluation didn’t show a significant correlation between the percentage of fish in feedingstuffs and the contamination level.

  6. Drug development, radiolabelled drugs and PET

    NARCIS (Netherlands)

    Vaalburg, W; Hendrikse, NH; de Vries, EFJ

    1999-01-01

    Positron emission tomography (PET) provides noninvasive in vivo quantitative pharmacokinetic and pharmacodynamic information on novel and established drugs. Because only very low amounts of the (potential) drug have to be administered, far below toxicity levels, human studies can be carried out even

  7. Positron emission tomography (PET) in endocrine tumours ...

    African Journals Online (AJOL)

    endocrine pancreatic tumours is probably limited to those that are less well differentiated and metabolically active. However, a future role for PET imaging in the detection of endocrine tumours, using more specific substrates, appears very promising. Journal of Endocrinology, Metabolism and Diabetes of South Africa Vol.

  8. PET and SPECT of neurobiological systems

    Energy Technology Data Exchange (ETDEWEB)

    Dierckx, Rudi A.J.O. [Groningen Univ. (Netherlands). Dept. of Nuclear Medicine and Molecular Imaging; Gent Univ. (Belgium). Dept. of Nuclear Medicine; Otte, Andreas [Univ. of Applied Sciences, Offenburg (Germany). Faculty of Electrical Engineering and Information Technology; Vries, Erik F.J. de; Waarde, Aren van (eds.) [Groningen Univ. (Netherlands). Dept. of Nuclear Medicine and Molecular Imaging

    2014-04-01

    Addresses a variety of aspects of neurotransmission in the brain. Details the latest results in probe development. Emphasis on a multidisciplinary approach. Written by internationally acclaimed experts. PET and SPECT of Neurobiological Systems combines the expertise of renowned authors whose dedication to the development of novel probes and techniques for the investigation of neurobiological systems has achieved international recognition. Various aspects of neurotransmission in the brain are discussed, such as visualization and quantification of (more than 20 different) neuroreceptors, neuroinflammatory markers, transporters, and enzymes as well as neurotransmitter synthesis, ?-amyloid deposition, cerebral blood flow, and the metabolic rate of glucose. The latest results in probe development are also detailed. Most chapters are written jointly by radiochemists and nuclear medicine specialists to ensure a multidisciplinary approach. This state of the art compendium will be valuable to anyone in the field of clinical or preclinical neuroscience, from the radiochemist and radiologist/nuclear medicine specialist to the interested neurobiologist and general practitioner. It is the second volume of a trilogy on PET and SPECT imaging in the neurosciences. Other volumes focus on PET and SPECT in psychiatry and PET and SPECT in neurology''.

  9. Maillard reaction products in pet foods

    NARCIS (Netherlands)

    Rooijen, van C.

    2015-01-01

    Pet dogs and cats around the world are commonly fed processed commercial foods throughout their lives. Often heat treatments are used during the processing of these foods to improve nutrient digestibility, shelf life, and food safety. Processing is known to induce the Maillard reaction, in which a

  10. Uterine disorders in 50 pet rabbits.

    Science.gov (United States)

    Künzel, Frank; Grinninger, Petra; Shibly, Sarina; Hassan, Jasmin; Tichy, Alexander; Berghold, Petra; Fuchs-Baumgartinger, Andrea

    2015-01-01

    Although the incidence of uterine disorders in pet rabbits is high there are only a few retrospective studies and case reports on genital tract disease in female rabbits. Uterine disorders were assessed in 50 pet rabbits. In 31 pet rabbits with suspected clinical uterine disease, medical records were further reviewed regarding clinical signs, diagnostic workup, treatment as well as the outcome itself. Uterine adenocarcinoma (54%) was most frequently diagnosed, followed by endometrial hyperplasia (26%). Serosanguineous vaginal discharge was the predominant clinical sign observed by the rabbit owners. In approximately 50% of the rabbits with suspected uterine disorders, abdominal palpation revealed enlarged and/or irregular masses in the caudoventral abdomen indicating uterine lesions. Out of 23 rabbits undergoing ovariohysterectomy, four were either euthanized or died shortly after surgery because they were clinically unstable. Overall, 80% of the ovariohysterectomized animals were still alive 6 mo after surgery. In female pet rabbits that are not breeding, either ovariohysterectomy should be performed at an early age or routine checks including ultrasonography of the abdomen are recommended on a regular basis.

  11. PET imaging in patients with Modic changes

    DEFF Research Database (Denmark)

    Albert, Hanne; Pedersen, Henrik; Manniche, Claus

    2009-01-01

    The aim of this study was via PET imaging to reveal if any highly metabolic processes were occurring in Modic changes type 1 and/or in the adjacent discs. Modic changes (MC) are signal changes in the vertebral endplate and body visualised by magnetic resonance imaging (MRI). MC are strongly...... disc. All patients had a PET scan using FDG (18F-fluorodeoxyglucose) as tracer. RESULTS: Included in the study were 11 patients, 4 women and 7 men, mean age 48.1 year (range 20-65). All MC were situated in the vertebrae both above and below the previously herniated disc/discs. Ten patients had MC at 1...... level, and 1 had MC at 2 levels. The affected levels were 1 at L2/L3, 6 at L4 /L5, and 5 at L5/S1. All had a previous disc herniation and MC larger than 4 mm in diameter. Technically satisfactory PET scans were obtained. However, PET imaging showed no increases in metabolism in any vertebra or disc...

  12. A PET scanner developed by CERN

    CERN Multimedia

    Laurent Guiraud

    1998-01-01

    This image shows a Position Emission Tomography (PET) scanner at the Hopital Cantonal Universitaire de Genève. Development of the multiwire proportional chamber at CERN in the mid-1970s was soon seen as a potential device for medical imaging. It is much more sensitive than previous devices and greatly reduced the dose of radiation received by the patient.

  13. 36 CFR 1002.15 - Pets.

    Science.gov (United States)

    2010-07-01

    ... possession of pets by the Board. This paragraph shall not apply to guide dogs accompanying visually impaired persons or hearing ear dogs accompanying hearing-impaired persons. (2) Failing to crate, cage, restrain on... section does not apply to dogs used by authorized Federal, State and local law enforcement officers in the...

  14. Eye Removal Surgeries in Exotic Pets.

    Science.gov (United States)

    Diehl, Kathryn A; McKinnon, Jo-Ann

    2016-01-01

    This article covers considerations and techniques of eye removal surgeries in exotic pets. After issues including surgical indications, anesthesia, patient preparation, and instrumentation are explored, surgical techniques are described. Enucleation/exenteration and modified evisceration are discussed, with species-specific nuances of small mammals, birds, reptiles, snakes, amphibians, and fish highlighted. Copyright © 2016 Elsevier Inc. All rights reserved.

  15. Fundamentals of quantitative PET data analysis

    NARCIS (Netherlands)

    Willemsen, ATM; van den Hoff, J

    2002-01-01

    Drug analysis and development with PET should fully exhaust the ability of this tomographic technique to quantify regional tracer concentrations in vivo. Data evaluation based on visual inspection or assessment of regional image contrast is not sufficient for this purpose since much of the

  16. Captive Conditions of Pet Lemurs in Madagascar.

    Science.gov (United States)

    Reuter, Kim E; Schaefer, Melissa S

    2016-01-01

    Live extraction of wildlife is a threat to biodiversity and can compromise animal welfare standards. Studies of the captive environments and welfare of pet primates are known, but none has focused on Madagascar. We aimed to expand knowledge about the captive conditions of pet lemurs in Madagascar. We hypothesized that captive lemurs would often be kept in restrictive settings, including small cages, would be fed foods inconsistent with their natural diets and, as a result, would be in bad physical or psychological health. Data were collected via a web-based survey (n = 253 reports) and from the websites and social media pages of 25 hotels. Most lemurs seen by respondents were either kept on a rope/leash/chain or in a cage (67%), though some lemurs were habituated and were not restrained (28%). Most of the time (72%) cages were considered small, and lemurs were rarely kept in captivity together with other lemurs (81% of lemurs were caged alone). Pet lemurs were often fed foods inconsistent with their natural diets, and most (53%) were described as being in bad health. These findings point to a need to undertake outreach to pet lemur owners in Madagascar about the captivity requirements of primates. © 2016 S. Karger AG, Basel.

  17. People Can Catch Diseases from Their Pets

    Centers for Disease Control (CDC) Podcasts

    2013-01-23

    Dr. Carol Rubin, Associate Director for Zoonoses and One Health at CDC, discusses zoonotic diseases in pets.  Created: 1/23/2013 by National Center for Emerging and Zoonotic Infectious Diseases (NCEZID).   Date Released: 1/28/2013.

  18. Dynamic comparison of PET imaging performance between state-of-the-art ToF-PET/CT and ToF-PET/MR scanners

    Energy Technology Data Exchange (ETDEWEB)

    Delso, Gaspar; Deller, Tim; Khalighi, Mehdi [GE Healthcare (Switzerland); Veit-Haibach, Patrick; Schulthess, Gustav von [University Hospital of Zurich (Switzerland)

    2014-07-29

    The goal of the present work was to determine the potential for dose reduction in a new clinical ToF-PET/MR scanner. This was achieved by means of long dynamic phantom acquisitions designed to provide a fair comparison of image quality and lesion detectability, as a function of activity, between the new PET/MR system and a state-of-the art PET/CT.

  19. Evaluation of Dixon Sequence on Hybrid PET/MR Compared with Contrast-Enhanced PET/CT for PET-Positive Lesions

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Ju Hye; Cho, Ihn Ho; Kong, Eun Jung; Chun, Kyung Ah [Yeungnam Univ. Hospital, Daegu (Korea, Republic of)

    2014-03-15

    Hybrid positron emission tomography and magnetic resonance (PET/MR) imaging performs a two-point Dixon MR sequence for attenuation correction. However, MR data in hybrid PET/MR should provide anatomic and morphologic information as well as an attenuation map. We evaluated the Dixon sequence of hybrid PET/MR for anatomic correlation of PET-positive lesions compared with contrast-enhanced PET/computed tomography (CT) in patients with oncologic diseases. Twelve patients underwent a single injection, dual imaging protocol. PET/CT was performed with an intravenous contrast agent (85±13 min after {sup 18}F-FDG injection of 403± 45 MBq) and then (125±19 min after injection) PET/MR was performed. Attenuation correction and anatomic allocation of PET were performed using contrast-enhanced CT for PET/CT and Dixon MR sequence for hybrid PET/MR. The Dixon MR sequence and contrast-enhanced CT were compared for anatomic correlation of PET-positive lesions (scoring scale ranging from 0 to 3 for visual ratings). Additionally, standardized uptake values (SUVs) for the detected lesions were assessed for quantitative comparison. Both hybrid PET/MR and contrast-enhanced PET/CT identified 55 lesions with increased FDG uptake in ten patients. In total, 28 lymph nodes, 11 bone lesions, 3 dermal nodules, 3 pleural thickening lesions, 2 thyroid nodules, 1 pancreas, 1 liver, 1 ovary, 1 uterus, 1 breast, 1 soft tissue and 2 lung lesions were present. The best performance was observed for anatomic correlation of PET findings by the contrast-enhanced CT scans (contrast-enhanced CT, 2.64± 0.70; in-phase, 1.29±1.01; opposed-phase, 1.29±1.15; water-weighted, 1.71±1.07; fat weighted, 0.56±1.03). A significant difference was observed between the scores obtained from the contrast-enhanced CT and all four coregistered Dixon MR images. Quantitative evaluation revealed a high correlation between the SUVs measured with hybrid PET/MR (SUVmean, 2.63±1.62; SUVmax, 4.30±2.88) and contrast

  20. Preliminary experience of coincidence PET in oncology

    Energy Technology Data Exchange (ETDEWEB)

    Park, C. H.; Yoon, S. N.; Joh, C. W.; Hwang, K. H.; Kim, Su Zy; Lim, S. M.; Yang, S. D. [Korea Cancer Ceter, Seoul (Korea, Republic of)

    1998-07-01

    Recently more medical centers in the western world are interested in the coincidence (CoDe) PET using a dual head gamma camera since its cost is about one tenth of the conventional PET, low cost to maintain and operate, and able to perform other routine planar and SPECT imaging studies. Elscint's Varicam is able to perform planar, SPECT, 511keV SPECT and CoDe PET. One such system with 5/8' crystals was installed at Ajou University Hospital early this year. Forty one patients with various cancers underwent F-18-FDG CoDe PET of the various anatomic sites. The patients were injected with 3-10mCi of F-18-FDG, supplied by the Korea Cancer Center Hospital, following more than 4 hr fasting. After 45-60 mimutes uptake period, raw data were acquired for 30 minutes by 10 clockwise continuous revolutions using a slip ring type gantry. Data acquisition was 3-D using only a filter / horizontal septae combination system in order to eliminate scatter and residual activity from the brain bladder. The data processed similar to SPECT in short axis, sagittal and coronal slices as well as reporjection profile. Coincidence subset expectation minimization (COSEM) iterative reconstruction algorithm was not available for the studies. Images were interpreted subjectively for unavailability of quantitative method of the system. Results of the study is tabulized and representive interesting cases will be shown. In conclusion, F-18-FDG CoDe PET was useful in diagnosis, staging and detection of recurrence of residual cancers. Draw backs of our study include, lack of specificities, inability to obtain WB and inability to quantitative F-18-FDG uptake. We believe these limitations will be resolved gradually in the future.

  1. Pet ownership and older women: the relationships among loneliness, pet attachment support, human social support, and depressed mood.

    Science.gov (United States)

    Krause-Parello, Cheryl A

    2012-01-01

    Pets can play a positive role in the both the physical and psychological health of older adults. This cross sectional study investigated the relationships among loneliness, pet attachment support, human social support, and depressed mood in a convenience sample of 159 pet-owning older women residing in the community. Participants completed loneliness, pet attachment support, human social support, and depressed mood scales. The results supported significant relationships between loneliness, pet attachment support, human social support, and depressed mood. No relationship was found between human social support and depressed mood. Pet attachment support, but not human social support, influenced the relationship between loneliness and depressed mood indicating the importance of pet attachment as a greater form of support in this sample. Clinical and social implications for nurses working with the geriatric population were identified and discussed. Copyright © 2012 Mosby, Inc. All rights reserved.

  2. Semiquantitative Assessment of (18)F-FDG Uptake in the Normal Skeleton: Comparison Between PET/CT and Time-of-Flight Simultaneous PET/MRI.

    Science.gov (United States)

    Minamimoto, Ryogo; Xu, Guofan; Jamali, Mehran; Holley, Dawn; Barkhodari, Amir; Zaharchuk, Greg; Iagaru, Andrei

    2017-11-01

    Differences in the attenuation correction methods used in PET/CT scanners versus the newly introduced whole-body simultaneous PET/MRI reportedly result in differences in standardized uptake values (SUVs) in the normal skeleton. The aim of the study was to compare the semiquantitative FDG uptake in the normal skeleton using time-of-flight (TOF) PET/MRI versus PET/CT with and without TOF. Participants received a single FDG injection and underwent non-TOF and TOF PET/CT (n = 23) or non-TOF PET/CT and TOF PET/MRI (n = 50). Mean SUV (SUVmean) and maximum SUV (SUVmax) were measured from all PET scans for nine normal regions of the skeleton. Pearson correlation coefficients (r) were used to evaluate the SUVmax and SUVmean of normal skeleton between non-TOF and TOF PET/CT, as well as between non-TOF PET/CT and TOF PET/MRI. In addition, percentage differences in SUVmax and SUVmean of the normal skeleton between non-TOF and TOF PET/CT and between non-TOF PET/CT and TOF PET/MRI were evaluated. The SUVmax and SUVmean in the normal skeleton significantly increased between non-TOF and TOF PET/CT, but they significantly decreased between non-TOF PET/CT and TOF PET/MRI. The SUVmax and SUVmean in normal skeleton showed good correlation between non-TOF PET/CT and TOF PET/MRI (SUVmax, r = 0.88; SUVmean, r = 0.91) and showed a similar trend between non-TOF and TOF PET/CT (SUVmax, r = 0.88; SUVmean, r = 0.94). In the normal skeleton, SUVmax and SUVmean showed high correlations between PET/MRI and PET/CT. The MRI attenuation correction used in TOF PET/MRI provides reliable semiquantitative measurements in the normal skeleton.

  3. Pet ownership among homeless youth: associations with mental health, service utilization and housing status.

    Science.gov (United States)

    Rhoades, Harmony; Winetrobe, Hailey; Rice, Eric

    2015-04-01

    As many as 25 % of homeless persons have pets. To our knowledge, pet ownership has not been studied quantitatively with homeless youth. This study examined pet ownership among 398 homeless youth utilizing two Los Angeles drop-in centers. Twenty-three percent of homeless youth had a pet. The majority of pet owners reported that their pets kept them company and made them feel loved; nearly half reported that their pets made it more difficult to stay in a shelter. Pet owners reported fewer symptoms of depression and loneliness than their non-pet owning peers. Pet ownership was associated with decreased utilization of housing and job-finding services, and decreased likelihood of currently staying in a shelter. These findings elucidate many of the positive benefits of pet ownership for homeless youth, but importantly highlight that pet ownership may negatively impact housing options. Housing and other services must be sensitive to the needs of homeless youth with pets.

  4. Reproducibility and repeatability of same-day two sequential FDG PET/MR and PET/CT.

    Science.gov (United States)

    Groshar, David; Bernstine, Hanna; Goldberg, Natalia; Nidam, Meital; Stein, Dan; Abadi-Korek, Ifat; Domachevsky, Liran

    2017-04-05

    To determine PET/CT and PET/MR reproducibility and PET/MR repeatability of fluorine 18 fluorodeoxyglucose (FDG) uptake measurements in tumors in cancer patients. This IRB approved prospective study was performed between October 2015 and February 2016 in consecutive patients who performed same day PET/CT and two sequential PET/MR. Thirty three patients with visible tumors (N = 63) were included. SUV for body weight (SUV) and lean body mass (SUL) were obtained. Volume of interest (VOI) with a threshold of 40% was used and SUV/L's, metabolic tumor volume (MTV) and tumor to liver ratio (T/L) were calculated. Measurements were plotted in a scattered diagram to visually identify correlation, a regression line was drawn and the equation of the line was calculated. Bland-Altman plots expressed as percentages were constructed to assess the agreement between measurements. The maximal clinically acceptable limits range was defined as ±30%. Lesional SUV's, SUL's and MTV corrected to body weight (BW) and lean body mass (LBM) demonstrated strong positive linear correlation between PET/CT and PET/MR and between two sequential PET/MR. The 95% limits of agreement ranged from -27.7 to 17.5 with a mean of -5.1 and -27.6 to 17.9 with a mean of -4.9 for SUVpeak and SULpeak, respectively for sequential PET/MR. Other PET metrics demonstrated limits range that is above ±30% between PET/CT and PET/MR and between two sequential PET/MR. PET/MR SUV/L peak has a clinically acceptable repeatability performance and can be used to evaluate the response to treatment.

  5. Impact of Ge-68/Ga-68-based versus CT-based attenuation correction on PET.

    NARCIS (Netherlands)

    Dalen, J.A. van; Visser, E.P.; Vogel, W.V.; Corstens, F.H.M.; Oyen, W.J.G.

    2007-01-01

    Transmission (Tx) scans are used in PET for attenuation correction (AC). For standalone PET this is typically done using Ge-68/Ga-68 sources, for PET-CT using CT. Therefore, standalone PET suffers from emission contamination during Tx scans, PET-CT does not. Here, we studied the effects of AC across

  6. A survey of attitudes toward responsible pet ownership.

    Science.gov (United States)

    Selby, L A; Rhoades, J D; Hewett, J E; Irvin, J A

    1979-01-01

    The concerns of medical and community officials about responsible pet ownership have increased. Before a practical solution can be found for irresponsible ownership and community health problems associated with pet populations, the public's attitudes on issues related to responsible pet ownership must be determined. Such issues include attitudes on dog and cat overpopulation, potential public health problems associated with pet populations, and methods of controlling pet populations and stray animals. Responses to a questionnaire were used to evaluate the attitudes of 910 pet owners and nonowners toward factors comprising responsible pet ownership. The median age of the respondents was 33 years; 414 (45 percent) were men, and 496 (55 percent) were women. At the time of the study, 18 percent owned a cat and a dog, 35 percent owned only a dog, 11 percent showed only a cat, and 36 percent were nonowners. Not only the sex of the respondent but also the category of pet ownership affected opinions on overpopulation of dogs and cats, nuisance and pollution problems associated with these animals, and methods of controlling pet populations in the community. For example, owners agreed strongly on family planning for pets, but a majority of male owners stated that they would not have their dogs neutered.

  7. Feasibility of simultaneous PET/MR of the carotid artery

    DEFF Research Database (Denmark)

    Ripa, Rasmus S; Knudsen, Andreas; Hag, Anne Mette F

    2013-01-01

    The study aimed at comparing PET/MR to PET/CT for imaging the carotid arteries in patients with known increased risk of atherosclerosis. Six HIV-positive men underwent sequential PET/MR and PET/CT of the carotid arteries after injection of 400 MBq of (18)F-FDG. PET/MR was performed a median of 131...... between PET data acquired using the PET/MR system compared to the PET/CT system. The mean difference for SUVmean was -0.18 (p PET/MR system. The 95% limits of agreement were -0.55 to 0.......20 for SUVmean and -0.93 to 0.65 for SUVmax. The image quality of the PET/MR allowed for delineation of the carotid vessel wall. The correlations between (18)F-FDG uptake from ROI including both vessel wall and vessel lumen to ROI including only the wall were strong (r = 0.98 for SUVmean and r = 1.00 for SUVmax...

  8. Pet ownership increases human risk of encountering ticks.

    Science.gov (United States)

    Jones, E H; Hinckley, A F; Hook, S A; Meek, J I; Backenson, B; Kugeler, K J; Feldman, K A

    2018-02-01

    We examined whether pet ownership increased the risk for tick encounters and tickborne disease among residents of three Lyme disease-endemic states as a nested cohort within a randomized controlled trial. Information about pet ownership, use of tick control for pets, property characteristics, tick encounters and human tickborne disease were captured through surveys, and associations were assessed using univariate and multivariable analyses. Pet-owning households had 1.83 times the risk (95% CI = 1.53, 2.20) of finding ticks crawling on and 1.49 times the risk (95% CI = 1.20, 1.84) of finding ticks attached to household members compared to households without pets. This large evaluation of pet ownership, human tick encounters and tickborne diseases shows that pet owners, whether of cats or dogs, are at increased risk of encountering ticks and suggests that pet owners are at an increased risk of developing tickborne disease. Pet owners should be made aware of this risk and be reminded to conduct daily tick checks of all household members, including the pets, and to consult their veterinarian regarding effective tick control products. © 2017 Blackwell Verlag GmbH.

  9. PKU-PET-II: A novel SiPM-based PET imaging system for small animals

    Science.gov (United States)

    Xie, Zhaoheng; Li, Suying; Zhou, Kun; Vuletic, Ivan; Meng, Xiangxi; Zhu, Sihao; Xu, Huan; Yang, Kun; Xu, Baixuan; Zhang, Jinming; Ren, Qiushi

    2018-01-01

    The objective of this study was to introduce, describe, and validate the performance of a novel preclinical silicon photomultiplier (SiPM)-based PET system (PKU-PET-II). Briefly, the detector assembly consisted of cerium-doped lutetium-yttrium oxyorthosilicate (LYSO) crystals, with dimensions of 2 ×2 ×15 mm3, that offered a 60 mm transaxial field of view (FOV) and 32 mm axial FOV, respectively. The compact front-end electronics readout and digital controller implemented architecture in the FPGA were noteworthy improvements in PKU-PET-II over its predecessor (PKU-PET-I). Based on the National Electrical Manufacturers Association (NEMA) NU 04-2008 standards, the design of the PKU-PET-II system was validated by a phantom experiment. The results presented spatial resolution (evaluated as full width at half maximum) with a system range from 1.68 ±0.07 to 2.31 ±0.03 mm at the FOV center and from 1.43 ±0.02 to 2.10 ±0.10 mm at the 1/4th axial FOV, respectively. The system's absolute sensitivity at the center position was 1.35% with the coincidence window of 6 ns and energy window of 300-700 keV. In addition, the NEMA image quality phantom and an animal study results validated the system imaging performance in preclinical imaging application. In conclusion, this SiPM-based, small-animal PET system (PKU-PET-II) provided higher-resolution, adequate sensitivity, and excellent image quality and has potential as a useful tool for real-time imaging of disease progression and development in vivo.

  10. Development of compact DOI-measurable PET detectors for simultaneous PET/MR Imaging

    Energy Technology Data Exchange (ETDEWEB)

    Shao, Yiping; Sun, Xishan [University of Texas MD Anderson Cancer Center (United States); Lou, Kai [Rice University (United States)

    2015-05-18

    It is critically needed yet challenging to develop compact PET detectors with high sensitivity and uniform, high imaging resolution for improving the performance of simultaneous PET/MR imaging, particularly for an integrated/inserted small-bore system. Using the latest “edge-less” SiPM arrays for DOI measurement using the design of dual-ended-scintillator readout, we developed several compact PET detectors suited for PET/MR imaging. Each detector consists of one LYSO array with each end coupled to a SiPM array. Multiple detectors can be seamlessly tiled together along all sides to form a large detector panel. Detectors with 1.5x1.5 and 2.0x2.0 mm crystals at 20 or 30 mm lengths were studied. Readout of individual SiPM or capacitor-based signal multiplexing was used to transfer 3D interaction position-coded analog signals through flexible-print-circuit cables to dedicated ASIC frontend electronics to output digital timing pulses that encode interaction information. These digital pulses can be transferred to, through standard LVDS cables, and decoded by a FPGA-based data acquisition positioned outside the MRI scanner for coincidence event selection. Initial detector performance measurement shows excellent crystal identification even with 30 mm long crystals, ~18% and 2.8 ns energy and timing resolutions, and around 2-3 mm DOI resolution. A large size detector panel can be scaled up with these modular detectors and different PET systems can be flexibly configured with the scalable readout electronics and data acquisition, providing an important design advantage for different system and application requirements. It is expected that standard shielding of detectors, electronics and signal transfer lines can be applied for simultaneous PET/MR imaging applications, with desired DOI measurement capability to enhance the PET performance and image quality.

  11. Validation of a simultaneous PET/MR system model for PET simulation using GATE

    Energy Technology Data Exchange (ETDEWEB)

    Monnier, Florian; Fayad, Hadi; Bert, Julien [LaTIM UMR 1101, Brest (France); Schmidt, Holger [University Hospital of Tübingen, Tübingen (Germany); Visvikis, Dimitris [LaTIM UMR 1101, Brest (France)

    2015-05-18

    Simultaneous PET/MR acquisition shows promise in a range of applications. Simulation using GATE is an essential tool that allows obtaining the ground truth for such acquisitions and therefore helping in the development and the validation of innovative processing methods such as PET image reconstruction, attenuation correction and motion correction. The purpose of this work is to validate the GATE simulation of the Siemens Biograph mMR PET/MR system. A model of the Siemens Biograph mMR was developed. This model includes the geometry and spatial positioning of the crystals inside the scanner and the characteristics of the detection process. The accuracy of the model was tested by comparing, on a real physical phantom study, GATE simulated results to reconstructed PET images using measured results obtained from a Siemens Biograph mMR system. The same parameters such as the acquisition time and phantom position inside the scanner were fixed for our simulations. List-mode outputs were recovered in both cases and reconstructed using the OPL-EM algorithm. Several parameters were used to compare the two reconstructed images such as profile comparison, signal-to-noise ratio and activity contrast analysis. Finally patient acquired MR images were segmented and used for the simulation of corresponding PET images. The simulated and acquired sets of reconstructed phantom images showed close emission values in regions of interest with relative differences lower than 5%. The scatter fraction was within a <3% agreement. Close matching of profiles and contrast indices were obtained between simulated and corresponding acquired PET images. Our results indicate that the GATE developed Biograph mMR model is accurate in comparison to the real scanner performance and can be used for evaluating innovative processing methods for applications in clinical PET/MR protocols.

  12. Simultaneous PET/MRI with (13)C magnetic resonance spectroscopic imaging (hyperPET): phantom-based evaluation of PET quantification.

    Science.gov (United States)

    Hansen, Adam E; Andersen, Flemming L; Henriksen, Sarah T; Vignaud, Alexandre; Ardenkjaer-Larsen, Jan H; Højgaard, Liselotte; Kjaer, Andreas; Klausen, Thomas L

    2016-12-01

    Integrated PET/MRI with hyperpolarized (13)C magnetic resonance spectroscopic imaging ((13)C-MRSI) offers simultaneous, dual-modality metabolic imaging. A prerequisite for the use of simultaneous imaging is the absence of interference between the two modalities. This has been documented for a clinical whole-body system using simultaneous (1)H-MRI and PET but never for (13)C-MRSI and PET. Here, the feasibility of simultaneous PET and (13)C-MRSI as well as hyperpolarized (13)C-MRSI in an integrated whole-body PET/MRI hybrid scanner is evaluated using phantom experiments. Combined PET and (13)C-MRSI phantoms including a NEMA [(18)F]-FDG phantom, (13)C-acetate and (13)C-urea sources, and hyperpolarized (13)C-pyruvate were imaged repeatedly with PET and/or (13)C-MRSI. Measurements evaluated for interference effects included PET activity values in the largest sphere and a background region; total number of PET trues; and (13)C-MRSI signal-to-noise ratio (SNR) for urea and acetate phantoms. Differences between measurement conditions were evaluated using t tests. PET and (13)C-MRSI data acquisition could be performed simultaneously without any discernible artifacts. The average difference in PET activity between acquisitions with and without simultaneous (13)C-MRSI was 0.83 (largest sphere) and -0.76 % (background). The average difference in net trues was -0.01 %. The average difference in (13)C-MRSI SNR between acquisitions with and without simultaneous PET ranged from -2.28 to 1.21 % for all phantoms and measurement conditions. No differences were significant. The system was capable of (13)C-MRSI of hyperpolarized (13)C-pyruvate. Simultaneous PET and (13)C-MRSI in an integrated whole-body PET/MRI hybrid scanner is feasible. Phantom experiments showed that possible interference effects introduced by acquiring data from the two modalities simultaneously are small and non-significant. Further experiments can now investigate the benefits of simultaneous PET and

  13. Does pet arrival trigger prosocial behaviors in individuals with autism?

    Directory of Open Access Journals (Sweden)

    Marine Grandgeorge

    Full Text Available Alteration of social interactions especially prosocial behaviors--an important aspect of development--is one of the characteristics of autistic disorders. Numerous strategies or therapies are used to improve communication skills or at least to reduce social impairments. Animal-assisted therapies are used widely but their relevant benefits have never been scientifically evaluated. In the present study, we evaluated the association between the presence or the arrival of pets in families with an individual with autism and the changes in his or her prosocial behaviors. Of 260 individuals with autism--on the basis of presence or absence of pets--two groups of 12 individuals and two groups of 8 individuals were assigned to: study 1 (pet arrival after age of 5 versus no pet and study 2 (pet versus no pet, respectively. Evaluation of social impairment was assessed at two time periods using the 36-items ADI-R algorithm and a parental questionnaire about their child-pet relationships. The results showed that 2 of the 36 items changed positively between the age of 4 to 5 (t(0 and time of assessment (t(1 in the pet arrival group (study 1: "offering to share" and "offering comfort". Interestingly, these two items reflect prosocial behaviors. There seemed to be no significant changes in any item for the three other groups. The interactions between individuals with autism and their pets were more--qualitatively and quantitatively--reported in the situation of pet arrival than pet presence since birth. These findings open further lines of research on the impact of pet's presence or arrival in families with an individual with autism. Given the potential ability of individuals with autism to develop prosocial behaviors, related studies are needed to better understand the mechanisms involved in the development of such child-pet relationship.

  14. Adhesion of Pet/psma Interfaces Reinforced with Plasma Treatment

    Science.gov (United States)

    Dai, Chi-An; Tsui, Tai-An; Cheng, Yao-Yi

    The interface between biaxially oriented poly (ethylene terephthalate) (PET) films and poly (styrene-co-maleic anhydride) (PSMA) was reinforced by nitrogen plasma treatment of PET film and subsequent annealing treatment of the PET/PSMA bi-material. The fracture toughness, Gc, of the interface was quantitatively measured using an asymmetric double cantilever beam test (ADCB). X-ray photoelectron spectrometry (XPS) was used to measure the change in the surface composition of PET films upon plasma treatment and correlate the fracture toughness of the interface. The fracture energy of PET/PSMA interface is significantly enhanced by annealing the plasma treated PET with PSMA at a temperature greater than the glass transition temperature of PSMA (~ 120°C). At an annealing temperature of 150°C, Gc increases with increasing plasma treatment time and reaches a plateau value of ~ 100-120 J/m2, a two order of magnitude increase in Gc compared with that of samples annealed at 130°C. The enhancement of the adhesion is resulted from the in-situ formation of copolymers due to reaction between amine functional groups from the plasma treatment and anhydride groups from PSMA. For plasma treatment time < 10 s, scanning electron microscope (SEM) measurement show that the fracture surface is relatively smooth indicating an interfacial failure between PET/PSMA. With increasing plasma treatment time and therefore increasing the amount of nitrogen functional groups on PET surface, large plastic deformation takes place at the PET/PSMA interface. For treatment time ≥ 100-150 s, the PET/PSMA interface becomes stronger than PET bulk material and consequently crack deviates from the interface and the failure occurs within the PET film. The interlayer fracture energy of a biaxially oriented PET film can thus be quantitatively measured with a Gc value of roughly 120 J/m2.

  15. Desenvolvimento de modelo conceitual de telha ecológica a partir de resíduos de PET e gesso da construção

    Directory of Open Access Journals (Sweden)

    S. Teske

    2015-06-01

    Full Text Available Este trabalho apresenta o gesso na construção civil, suas aplicações, características e o desperdício associado. É exposta a legislação brasileira pertinente ao gerenciamento dos resíduos sólidos na construção, e mais especificamente as resoluções CONAMA 307/02 e 431/11, em que o resíduo de gesso passou a ter uma reclassificação quanto a sua destinação. Assim, esse passou a ser considerado um material passível de reutilização e reciclagem. Dessa forma, o objetivo do trabalho foi investigar a viabilidade técnica de aproveitamento de resíduos de gesso como matéria-prima para materiais de construção, no caso, pela incorporação deste em telhas. Assim, é feita uma descrição dos tipos de telhas, suas características e métodos de fabricação, como também a exposição de dois tipos de telhas recicladas. É descrito também o albedo, associado com o benefício de telhados brancos na redução da temperatura dentro das edificações nos dias de maior calor. Foi feita uma lista com as formas e cobrimentos possíveis para a adaptação do gesso na telha, e a partir de características favoráveis às telhas foi escolhido o modelo a ser detalhado, a partir de uma matriz avaliativa. O modelo escolhido foi o Colonial Gigante, com capa polimérica feita de resíduo de PET (politereftaleno de etileno envolvendo o resíduo de gesso. Um modelo 3D foi desenvolvido, e a telha foi nomeada de Telha GePET. Foram definidas em laboratório a umidade e a massa específica aparente e unitária do resíduo de gesso. Diversas características da telha foram descritas, como suas dimensões, massa, fonte de matéria-prima, produção, instalação no telhado, manutenção e durabilidade, o descarte após sua vida útil, o albedo, o isolamento térmico e o valor da telha. Concluiu-se que é possível a fabricação de uma telha com resíduos de gesso, juntamente com o resíduo de PET, tornando-a um produto mais sustentável e 100% reciclável.

  16. Ethylene evolution and endo-beta-mannanase activity during lettuce seed germination at high temperature Evolução de etileno e atividade da enzima endo-beta-mananase durante a germinação de sementes de alface sob altas temperaturas

    Directory of Open Access Journals (Sweden)

    Warley Marcos Nascimento

    2004-04-01

    Full Text Available High temperatures during lettuce seed imbibition can delay or completely inhibit germination and the endosperm layer appears to restrict the radicle protrusion. The role of endo-beta-mannanase during lettuce seed germination at 35°C and the influence of ethylene in endo-beta-mannanase regulation were investigated. Seeds of 'Dark Green Boston' (DGB and 'Everglades' (EVE were germinated in water, or 10 mmol L-1 of 1-aminocyclopropane-1-carboxylic acid (ACC, or 10 mmol L-1 of aminoethoxyvinylglycine (AVG, or 20 mmol L-1 of silver thiosulphate (STS. Seeds were also primed in polyethylene glycol (PEG, or PEG + ACC, PEG + AVG, or PEG + STS. Untreated seeds germinated 100% at 20°C. At 35°C, EVE seeds germinated 100%, whereas DGB seeds germinated only 33%. Seed priming or adding ACC during incubation increased germination at 35°C. Higher ethylene evolution was detected in EVE than in DGB during germination at 35°C. AVG did not inhibit seed germination of DGB at 35°C, but STS did. Higher endo-beta-mannanase activity was observed in EVE compared with DGB seeds. Providing ACC either during priming or during germination increased endo-beta-mannanase activity, whereas AVG and STS led to decreased or no activity. Ethylene may overcome the inhibitory effect of high temperature in thermosensitive lettuce seeds due to increased endo-beta-mannanase, possibly leading to weakening of the endosperm.Altas temperaturas durante a embebição das sementes de alface podem atrasar ou inibir a germinação e o endosperma parece ser o responsável na restrição da protrusão da radícula. O envolvimento da enzima endo-beta-mananase durante a germinação de sementes de alface a 35°C e a influência do etileno na regulagem desta enzima foram estudados. Sementes das cultivares Dark Green Boston (DGB e Everglades (EVE foram germinadas em água ou em soluções de 10 mmol L-1 de 1-aminociclopropano-1-ácido carboxilico (ACC, 10 mmol L-1 de amino-etoxi-vinil-glicina (AVG

  17. Atividade respiratória e produção de etileno em laranja ‘Pêra’ submetida a níveis de processamento mínimo e temperaturas de armazenamento Respiratory activity and ethylene production in ‘Pera’ orange submitted to different levels of processing and storage temperature

    Directory of Open Access Journals (Sweden)

    Maria Cecília de Arruda

    2008-12-01

    Full Text Available O objetivo deste trabalho foi avaliar o efeito de diferentes níveis de processamento e temperaturas de armazenamento na atividade respiratória e na produção de etileno de laranja 'Pêra' minimamente processada. O experimento foi realizado em duas etapas. Na primeira, as laranjas lavadas, sanificadas e resfriadas foram submetidas aos processamentos: a segmentos; b inteiras sem albedo; c inteiras com albedo; d intactas (controle. As laranjas minimamente processadas foram armazenadas a 6ºC. Na segunda etapa, as laranjas sem albedo foram armazenadas a 1; 11; 21 e 31ºC. A atividade respiratória e a produção de etileno eram determinadas imediatamente após o processamento; a cada hora, durante 10 horas, e a cada 24 horas, durante sete dias. O delineamento utilizado foi o inteiramente casualizado, com seis repetições por tratamento. O processamento interferiu na atividade respiratória, que foi maior imediatamente após o descascamento e a separação dos segmentos. O processamento das laranjas na forma inteira, com ou sem albedo, afetou a atividade respiratória das mesmas somente nas primeiras horas após o processamento. Durante todo período de armazenamento, a atividade respiratória das laranjas a 1º e 11ºC não diferiu entre si, sendo inferior à das laranjas a 21º e 31ºC. O etileno foi detectado apenas nos frutos mantidos a 21º e 31ºC. Os quocientes de temperatura, após a estabilização, eram 1,73 para 1-11ºC, 2,11 para 11-21ºC, e 1,54 para 21-31ºC. A atividade respiratória das laranjas foi influenciada pelos níveis de processamento e pela temperatura de armazenamento.The present work was aimed at evaluating the effect of different processing levels and storage temperatures on the respiratory activity and the ethylene production of minimally processed 'Pera' orange. The study was carried out in two stages. The first consisted of submitting the oranges previously washed, sanitized and chilled to the following processing

  18. Feasibility of simultaneous PET/MR of the carotid artery: first clinical experience and comparison to PET/CT

    DEFF Research Database (Denmark)

    Ripa, Rasmus Sejersten; Knudsen, Andreas; Hag, Anne Mette Fisker

    2013-01-01

    The study aimed at comparing PET/MR to PET/CT for imaging the carotid arteries in patients with known increased risk of atherosclerosis. Six HIV-positive men underwent sequential PET/MR and PET/CT of the carotid arteries after injection of 400 MBq of 18F-FDG. PET/MR was performed a median of 131...... between PET data acquired using the PET/MR system compared to the PET/CT system. The mean difference for SUVmean was -0.18 (p PET/MR system. The 95% limits of agreement were -0.55 to 0.......20 for SUVmean and -0.93 to 0.65 for SUVmax. The image quality of the PET/MR allowed for delineation of the carotid vessel wall. The correlations between 18F-FDG uptake from ROI including both vessel wall and vessel lumen to ROI including only the wall were strong (r = 0.98 for SUVmean and r = 1.00 for SUVmax...

  19. PET-based geometrical calibration of a pinhole SPECT add-on for an animal PET scanner.

    Science.gov (United States)

    Deng, Xiao; Beaudoin, Jean-François; Cadorette, Jules; Naaman, Charles; Lecomte, Roger; Yao, Rutao

    2013-04-07

    We developed SPECT imaging capability on an animal PET scanner to provide a cost effective option for animal SPECT imaging. The SPECT add-on sub-system was enabled by mechanically integrating a multiple-pinhole collimator in the PET detector ring. This study introduces a method to calibrate the geometrical parameters of the SPECT add-on using the PET imaging capability of the scanner. The proposed PET imaging-based calibration method consists of two steps: (1) paint the pinhole apertures of the collimator with a positron emitting radioactive solution; and (2) image the collimator inside the scanner in PET mode. The geometrical parameters of the multi-pinhole SPECT add-on can then be derived directly from a set of PET images by simple linear calculation and used in defining the SPECT system. The method was compared to our implementation of a SPECT calibration approach with model-based fitting of SPECT projection data. The procedure for carrying out the PET imaging-based calibration method is simpler and faster than that of our implementation of the SPECT model-based calibration method. Since it does not require model fitting, the uniqueness of the calibration result is warranted. Better quality SPECT images were reconstructed using the PET-derived calibration parameters rather than our implementation of the SPECT model-based calibration parameters. We conclude that the proposed PET imaging-based calibration method provides a highly effective means for enabling SPECT imaging on a PET scanner.

  20. PET in diagnosing exocrine pancreatic cancer; PET bei Tumoren des exokrinen Pankreas

    Energy Technology Data Exchange (ETDEWEB)

    Bares, R.; Besenfelder, H.; Dohmen, B.M. [Abt. Nuklearmedizin, Radiologische Klinik des Universitaetsklinikums Tuebingen (Germany)

    2003-06-01

    Despite dramatic improvements in diagnostic imaging (ultrasonography, in particular endoscopic ultrasound, CT, MRI) treatment results of pancreatic cancer are still poor. Due to the lack of early symptoms, most tumors are diagnosed at an advanced stage of disease which excludes curative surgical treatment. FDG-PET has been shown to be effective in detecting pancreatic cancer as well as differentiating benign from malignant pancreatic tumors. Results might be further improved by applying quantitative analyses, in particular kinetic modelling of FDG metabolism. Nevertheless false negative as well as false positive findings may occur. Small lesions (lymphnode or liver metastases < 1 cm) might be missed, furthermore hyperglycemia often present in patients with pancreatic disease might reduce tumor uptake and subsequently tumor detectability by PET. False positive findings were reported in active pancreatitis and some benign tumors. Although PET proved to be superior to CT or ERCP in detecting cancer, clinical relevance of PET is limited due to the absence of therapeutic consequences to be derived from PET. As a consequence PET should only be used in patients with equivocal findings of morphological imaging (CT, ERCP) who are potential candidates for surgical treatment. (orig.) [German] Trotz verbesserter diagnostischer Moeglichkeiten (endoskopischer Ultraschall, Spiral-CT, MRT) sind die Behandlungsergebnisse bei Tumoren des exokrinen Pankreas nach wie vor unbefriedigend. Aufgrund der spaet einsetzenden klinischen Symptomatik wird die Diagnose meist erst bei lokaler Inoperabilitaet gestellt. Die FDG-PET has sich sowohl im Nachweis von Pankreaskarzinomen als auch bei der Differenzialdiagnose pankreatischer Raumforderungen bewaehrt und den etablierten bildgebenden Verfahren (Ultraschall, CT) als ueberlegen erwiesen. Weitere Verbesserungen erscheinen durch absolute Quantifizierung der FDG-Kinetik moeglich. Dennoch koennen falsch negative wie auch falsch positive Ergebnisse

  1. Foreign body reaction associated with PET and PET/chitosan electrospun nanofibrous abdominal meshes.

    Directory of Open Access Journals (Sweden)

    Beatriz Veleirinho

    Full Text Available Electrospun materials have been widely explored for biomedical applications because of their advantageous characteristics, i.e., tridimensional nanofibrous structure with high surface-to-volume ratio, high porosity, and pore interconnectivity. Furthermore, considering the similarities between the nanofiber networks and the extracellular matrix (ECM, as well as the accepted role of changes in ECM for hernia repair, electrospun polymer fiber assemblies have emerged as potential materials for incisional hernia repair. In this work, we describe the application of electrospun non-absorbable mats based on poly(ethylene terephthalate (PET in the repair of abdominal defects, comparing the performance of these meshes with that of a commercial polypropylene mesh and a multifilament PET mesh. PET and PET/chitosan electrospun meshes revealed good performance during incisional hernia surgery, post-operative period, and no evidence of intestinal adhesion was found. The electrospun meshes were flexible with high suture retention, showing tensile strengths of 3 MPa and breaking strains of 8-33%. Nevertheless, a significant foreign body reaction (FBR was observed in animals treated with the nanofibrous materials. Animals implanted with PET and PET/chitosan electrospun meshes (fiber diameter of 0.71 ± 0.28 µm and 3.01 ± 0.72 µm, respectively showed, respectively, foreign body granuloma formation, averaging 4.2-fold and 7.4-fold greater than the control commercial mesh group (Marlex. Many foreign body giant cells (FBGC involving nanofiber pieces were also found in the PET and PET/chitosan groups (11.9 and 19.3 times more FBGC than control, respectively. In contrast, no important FBR was observed for PET microfibers (fiber diameter = 18.9 ± 0.21 µm. Therefore, we suggest that the reduced dimension and the high surface-to-volume ratio of the electrospun fibers caused the FBR reaction, pointing out the need for further studies to elucidate the mechanisms

  2. Quantitative assessment of human and pet exposure to Salmonella associated with dry pet foods.

    Science.gov (United States)

    Lambertini, Elisabetta; Buchanan, Robert L; Narrod, Clare; Ford, Randall M; Baker, Robert C; Pradhan, Abani K

    2016-01-04

    Recent Salmonella outbreaks associated with dry pet foods and treats highlight the importance of these foods as previously overlooked exposure vehicles for both pets and humans. In the last decade efforts have been made to raise the safety of this class of products, for instance by upgrading production equipment, cleaning protocols, and finished product testing. However, no comprehensive or quantitative risk profile is available for pet foods, thus limiting the ability to establish safety standards and assess the effectiveness of current and proposed Salmonella control measures. This study sought to develop an ingredients-to-consumer quantitative microbial exposure assessment model to: 1) estimate pet and human exposure to Salmonella via dry pet food, and 2) assess the impact of industry and household-level mitigation strategies on exposure. Data on prevalence and concentration of Salmonella in pet food ingredients, production process parameters, bacterial ecology, and contact transfer in the household were obtained through literature review, industry data, and targeted research. A probabilistic Monte Carlo modeling framework was developed to simulate the production process and basic household exposure routes. Under the range of assumptions adopted in this model, human exposure due to handling pet food is null to minimal if contamination occurs exclusively before extrusion. Exposure increases considerably if recontamination occurs post-extrusion during coating with fat, although mean ingested doses remain modest even at high fat contamination levels, due to the low percent of fat in the finished product. Exposure is highly variable, with the distribution of doses ingested by adult pet owners spanning 3Log CFU per exposure event. Child exposure due to ingestion of 1g of pet food leads to significantly higher doses than adult doses associated with handling the food. Recontamination after extrusion and coating, e.g., via dust or equipment surfaces, may also lead to

  3. Does PET reconstruction method affect Deauville scoring in lymphoma patients?

    Science.gov (United States)

    Enilorac, Blandine; Lasnon, Charline; Nganoa, Cathy; Fruchart, Christophe; Gac, Anne Claire; Damaj, Gandhi; Aide, Nicolas

    2017-12-14

    Background: When scoring 18F-Fluorodeoxyglucose (FDG) positron emission tomography (PET) with the Deauville scale (DS), the quantification of tumor and reference organs limits the problem of optical misinterpretation. Compared to conventional reconstruction algorithms, point spread function (PSF) modeling significantly increases standardized uptake values (SUVs) in tumors but only moderately in the liver, which could affect the DS. We investigated whether the choice of the reconstruction algorithm affects the DS and whether discordances affect the capability of FDG PET to stratify lymphoma patients. Materials and Methods: Overall, 126 diffuse large B-cell Lymphoma (DLBCL) patients were included (56 females, 70 males, median (range) age: 65 (20-88) years). PET data were reconstructed with unfiltered PSF reconstruction. Additionally, a 6-mm filter was applied to PSF images to meet the European Association of Nuclear Medicine (EANM)/European Association Research Ltd (EARL) requirements (PSFEARL). One hundred interim PET (i-PET) and 95 end-of-treatment PET (EoT-PET) studies were analyzed. SUVmax in the liver and aorta were determined using automatic volumes of interest (VOIs) and compared to SUVmax of the residual mass with the highest FDG uptake. Results: For i-PET, using PSF and PSFEARL, patients were classified as responders and non-responders in 60 and 40 cases versus 63 and 37 cases, respectively. Five (5.0%) major discordances (i.e., changes from responder to non-responder) occurred. For Eot-PET, patients were classified using PSF and PSFEARL as responders and non-responders in 69 and 26 cases versus 72 and 23 cases, respectively. Three (3.2%) major discordances occurred. Concordance (Cohen's unweighted Kappa) between PSF and the PSFEARL Deauville scoring was 0.82 (95%CI: 0.73-0.91) for i-PET and 0.89 (95%CI: 0.81-0.96) for EoT-PET. The median follow-up periods were 28.4 and 27.4 months for i-PET and EoT-PET, respectively. Kaplan-Meier analysis showed

  4. 18F-FDG-PET/CT in the Staging and Management of Melanoma: A Prospective Multicenter Ontario PET Registry Study.

    Science.gov (United States)

    Singnurkar, Amit; Wang, Jonathan; Joshua, Anthony M; Langer, Deanna L; Metser, Ur

    2016-03-01

    The Ontario PET Registry was established to provide evidence on the clinical impact of 18-FDG-PET/CT (PET) imaging to inform Ontario Health Insurance Plan funding decisions. The melanoma registry assessed the use of melanoma staging by PET in advanced or high-risk melanoma as a useful adjunct to clinical and standard radiologic investigation. Between January 2011 and July 2013, approximately 319 consecutive patients with potentially resectable localized high-risk melanoma or recurrent disease under consideration for metastasectomy underwent PET imaging for staging across 9 institutions in Ontario. Pre-PET stage information was provided by the referring clinician and compared with post-PET stage. The ability of PET to reclassify disease from M0 to M1 status was assessed. The registry data were then linked to provincial administrative databases using deidentified health insurance numbers to determine PET stage-based rates of systemic therapy, radiotherapy, and surgery. There was a significant increase in stage to M1 status after PET in 56 of 319 patients (17.6%) (P < 0.0001). There was no significant relationship between upstaging with PET and the proportion of patients receiving radiation therapy (P = 0.066) or systemic therapy (P = 0.072). There was a significant relationship between upstaging with PET and the proportion of patients undergoing surgical resection of metastases distant to the primary melanoma site (P = 0.034). This prospective, multicenter registry of high-risk or advanced melanoma found that PET significantly upstages patients and impacts surgical management.

  5. The Maillard reaction and pet food processing: effects on nutritive value and pet health.

    Science.gov (United States)

    van Rooijen, Charlotte; Bosch, Guido; van der Poel, Antonius F B; Wierenga, Peter A; Alexander, Lucille; Hendriks, Wouter H

    2013-12-01

    The Maillard reaction, which can occur during heat processing of pet foods or ingredients, is known to reduce the bioavailability of essential amino acids such as lysine due to the formation of early and advanced Maillard reaction products (MRP) that are unavailable for utilisation by the body. Determination of the difference between total and reactive lysine by chemical methods provides an indication of the amount of early MRP present in foods, feeds and ingredients. Previous research reported that the difference between total and reactive lysine in pet foods can be up to 61.8%, and foods for growing dogs may be at risk of supplying less lysine than the animal may require. The endogenous analogues of advanced MRP, advanced glycation endproducts, have been associated with age-related diseases in humans, such as diabetes and impaired renal function. It is unknown to what extent advanced MRP are present in pet foods, and if dietary MRP can be associated with the development of diseases such as diabetes and impaired renal function in pet animals. Avoidance of ingredients with high levels of MRP and processing conditions known to favour the Maillard reaction may be useful strategies to prevent the formation of MRP in manufactured pet food. Future work should further focus on understanding the effects of ingredient choice and processing conditions on the formation of early and advanced MRP, and possible effects on animal health.

  6. SmartPET: Applying HPGe and pulse shape analysis to small-animal PET

    Energy Technology Data Exchange (ETDEWEB)

    Cooper, R.J. [Department of Physics, University of Liverpool (United Kingdom)], E-mail: rjc@ns.ph.liv.ac.uk; Boston, A.J.; Boston, H.C.; Cresswell, J.R.; Grint, A.N.; Mather, A.R.; Nolan, P.J.; Scraggs, D.P.; Turk, G. [Department of Physics, University of Liverpool (United Kingdom); Hall, C.J.; Lazarus, I. [CCLRC Daresbury Laboratory, Warrington, Cheshire (United Kingdom); Berry, A.; Beveridge, T.; Gillam, J.; Lewis, R.A. [School of Physics and Materials Engineering, Monash University, Melbourne (Australia)

    2007-08-21

    The SmartPET project is the development of a prototype small-animal imaging system based on the use of Hyperpure Germanium (HPGe) detectors. The use of digital electronics and application of Pulse Shape Analysis (PSA) techniques provide fine spatial resolution, while the excellent intrinsic energy resolution of HPGe detectors makes the system ideal for multi-nuclide imaging. As a result, the SmartPET system has the potential to function as a dual modality imager, operating as a dual-head Positron Emission Tomography (PET) camera or in a Compton Camera configuration for Single Photon Emission Computed Tomography (SPECT) imaging. In this paper, we discuss how the use of simple PSA techniques greatly improves the position sensitivity of the detector yielding improved spatial resolution in reconstructed images. The PSA methods presented have been validated by comparison to data from high-precision scanning of the detectors. Results from this analysis are presented along with initial images from the SmartPET system, which demonstrates the impact of these techniques on PET images.

  7. Reproducibility of (18)F-FDG PET uptake measurements in head and neck squamous cell carcinoma on both PET/CT and PET/MR

    DEFF Research Database (Denmark)

    Rasmussen, J H; Fischer, B M; Aznar, M C

    2015-01-01

    OBJECTIVE: To investigate reproducibility of fluorine-18 fludeoxyglucose ((18)F-FDG) uptake on (18)F-FDG positron emission tomography (PET)/CT and (18)F-FDG PET/MR scans in patients with head and neck squamous cell carcinoma (HNSCC). METHODS: 30 patients with HNSCC were included in this prospective...

  8. Practical Considerations for Clinical PET/MR Imaging.

    Science.gov (United States)

    Galgano, Samuel; Viets, Zachary; Fowler, Kathryn; Gore, Lael; Thomas, John V; McNamara, Michelle; McConathy, Jonathan

    2018-01-01

    Clinical PET/MR imaging is currently performed at a number of centers around the world as part of routine standard of care. This article focuses on issues and considerations for a clinical PET/MR imaging program, focusing on routine standard-of-care studies. Although local factors influence how clinical PET/MR imaging is implemented, the approaches and considerations described here intend to apply to most clinical programs. PET/MR imaging provides many more options than PET/computed tomography with diagnostic advantages for certain clinical applications but with added complexity. A recurring theme is matching the PET/MR imaging protocol to the clinical application to balance diagnostic accuracy with efficiency. Copyright © 2017 Elsevier Inc. All rights reserved.

  9. PET-CT og kolorektal cancer - retrospektivt studie

    DEFF Research Database (Denmark)

    Larsen, Anders Christian; Julie, Pedersen; Prakash, Vineet

    fusioneret Positron Emissions Tomografi (PET) og Computer : Den nye kombination af fusioneret Positron Emissions Tomografi (PET) og Computer Tomografi scanning (CT) har vist sig effektiv i udredningen af recidiv ved en lang række kræftformer inklusiv gastrointestinal cancer. Den anvendes desuden i...... udredningen af primært metastaserende cancer. Patienterne henvises til PET-CT, når der klinisk rejses mistanke om recidiv i form af symptomer eller biokemiske markørstigninger. Alternativt, hvis CT- og MRscanning ikke kan afklare problemstillingen. På nuværende tidspunkt er der ingen klare retningslinjer for...... modalitet som PET-CT i udredningsfasen, er det vigtig at evaluere brugen af denne. Vi har med dette materiale vist, at PET-CT kan have en plads i udredning af recidiv ved kolorectal cancer. Mistanke fra andre scanninger og CEA stigning bør få klinikeren til at henvise patienten til PET-CT, idet hovedparten...

  10. Effect of petting a dog on immune system function.

    Science.gov (United States)

    Charnetski, Carl J; Riggers, Sandra; Brennan, Francis X

    2004-12-01

    The present study assessed the effect of petting a dog on secretory immunoglobulin A (IgA) levels. 55 college students were randomly assigned to either an experimental group or one of two control groups. Group 1 (n= 19) petted a live dog; Group 2 (n = 17) petted a stuffed dog, while Group 3 (n = 19) simply sat comfortably on a couch. Each participant was exposed to one of the three conditions for 18 min. Pre- and posttreatment saliva samples yielded a significant increase in IgA for Group 1 only. Participants were also asked to complete the Pet Attitude Scale of Templer, Salter, Dickey, Baldwin and Veleber. Scores on this scale correlated with IgA increases only for participants in Group 2 (petting a stuffed animal). Results are discussed in terms of the beneficial effects of pets on health in general, and immunity in particular.

  11. Microfluidics for Synthesis of Peptide-Based PET Tracers

    Directory of Open Access Journals (Sweden)

    Yang Liu

    2013-01-01

    Full Text Available Positron emission tomography (PET is a powerful noninvasive tool for acquisition of the physiological parameters in human and animals with the help of PET tracers. Among all the PET tracers, radiolabeled peptides have been widely explored for cancer-related receptor imaging due to their high affinity and specificity to receptors. But radiochemistry procedures for production of peptide-based PET tracers are usually complex, which makes large-scale clinical studies relatively challenging. New radiolabeling technologies which could simplify synthesis and purification procedures, are extremely needed. Over the last decade, microfluidics and lab-on-a-chip (LOC technology have boomed as powerful tools in the field of organic chemistry, which potentially provide significant help to the PET chemistry. In this minireview, microfluidic radiolabeling technology is described and its application for synthesis of peptide-based PET tracers is summarized and discussed.

  12. Facile method to prepare a transparent superhydrophobic PET film

    Science.gov (United States)

    Wang, Jian; Chen, Hong; Wang, Xian; Yuan, Zhiqing

    2016-11-01

    A simple method to fabricate a transparent superhydrophobic coating was developed by spraying PDMS/SiO2 nanoparticles suspension on a hydrophilic PET film. This PDMS/SiO2 nanoparticles suspension was prepared by fully diluting and properly stirring. When this suspension was sprayed on the surface of PET film at a distance of about 30 cm for 2 s, a porous micro-nano-binary structure was formed, which endowed the hydrophilic PET film superhydrophobicity, while the PET film maintained transparent after spraying with a SiO2 nanoparticle layer. The as-prepared superhydrophobic PET film exhibited a high water contact angle of about 155° ± 1.9° and a low water sliding angle of about 7°. The formation mechanism of this transparent superhydrophobic coating on PET film was also discussed in detail in this paper.

  13. SU-F-I-57: Evaluate and Optimize PET Acquisition Overlap in 18F-FDG Oncology Wholebody PET/CT: Can We Scan PET Faster?

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, J; Natwa, M; Hall, NC; Knopp, MV [The Ohio State University, Columbus, OH (United States); Knopp, MU [Pepperdine University, Malibu, CA (United States); Zhang, B; Tung, C [Philips Healthcare, Highland Heights, OH (United States)

    2016-06-15

    Purpose: The longer patient has to remain on the table during PET imaging, the higher the likelihood of motion artifacts due to patient discomfort. This study was to investigate and optimize PET acquisition overlap in 18F-FDG oncology wholebody PET/CT to speed up PET acquisition and improve patient comfort. Methods: Wholebody 18F-FDG PET/CT of phantoms, 8 pre-clinical patients (beagles) and 5 clinical oncology patients were performed in 90s/bed on a time-of-flight Gemini TF 64 system. Imaging of phantoms and beagles was acquired with reduced PET overlaps (40%, 33%, 27%, 20%, 13% and no overlap) in addition to the system default (53%). In human studies, 1 or 2 reduced overlaps from the listed options were used to acquire PET/CT sweeps right after the default standard of care imaging. Image quality was blindly reviewed using visual scoring criteria and quantitative SUV assessment. NEMA PET sensitivity was performed under different overlaps. Results: All PET exams demonstrated no significant impact on the visual grades for overlaps >20%. Blinded reviews assigned the best visual scores to PET using overlaps 53%–27%. Reducing overlap to 27% for oncology patients (12-bed) saved an average of ∼40% acquisition time (11min) compared to using the default overlap (18min). No significant SUV variances were found when reducing overlap to half of default for cerebellum, lung, heart, aorta, liver, fat, muscle, bone marrow, thighs and target lesions (p>0.05), except expected variability in urinary system. Conclusion: This study demonstrated by combined phantom, pre-clinical and clinical PET/CT scans that PET acquisition overlap in axial of today’s systems can be reduced and optimized. It showed that a reduction of PET acquisition overlap to 27% (half of system default) can be implemented to reduce table time by ∼40% to improve patient comfort and minimize potential motion artifacts, without prominently degrading image quality or compromising PET quantification.

  14. Caraterização composicional do AES - um copolímero de enxertia de poli(estireno-co-acrilonitrila em poli(etileno-co-propileno-co-dieno Compositional characterization of AES a graft copolymer based on poly(styrene-co-acrylonitrile and poly(etyhlene-co-propylene-co-diene

    Directory of Open Access Journals (Sweden)

    Renato Turchet

    2006-06-01

    Full Text Available O objetivo deste trabalho é a caracterização do AES, um copolímero de enxertia de poli(estireno-co-acrilonitrila, SAN, em poli(etileno-co-propileno-co-dieno, EPDM. Para tanto, o AES foi submetido à extração seletiva de seus componentes: o SAN livre, o EDPM livre, e o copolímero de enxertia EPDM-g-SAN. O AES e suas frações foram caracterizados por espectroscopia de infravermelho, análise elementar, calorimetria diferencial de varredura e ressonância magnética nuclear, RMN¹H e RMN13C. O AES analisado apresenta a seguinte composição em massa: 65% de EPDM-g-SAN, 13% de EPDM livre e 22% de SAN livre. O EPDM apresenta 69,8% em massa de etileno, 26,5% em massa de propileno e 4,6% em massa do dieno, 2-etilideno-5-norboneno, ENB. O SAN apresenta razão em massa acrilonitrila/estireno de 28/72 e distribuição randômica de comonômeros de estireno e acrilonitrila. Estes resultados são concordantes com a composição do AES fornecida pelo fabricante, indicando que a metodologia proposta é adequada.This work aims the characterization of AES, a graft copolymer based on poly(styrene-co-acrylonitrile, SAN, and poly(etyhlene-co-propylene-co-diene, EPDM. AES was submitted to selective extraction of its components: free SAN, EPDM chains and the graft copolymer EPDM-g-SAN. AES and its fractions were characterized by infrared spectroscopy, elemental analysis, differential scanning calorimetry, 13C and ¹H nuclear magnetic resonance. The AES has 65 wt % of EPDM-g-SAN, 13 wt % of free EPDM and 22 wt % of free SAN. EPDM has 69.8 wt % of ethylene, 26.5 wt % of propylene and 4.6 wt % of diene, 2-ethylidene-5-norbonene ENB. SAN presents acrylonitrile/styrene mass ratio of 28/72 and a random distribution of acrylonitrile and styrene comonomers. These results are in agreement with the composition reported by the AES supplier, indicating that the proposed methodology is adequate.

  15. Avaliação do desempenho de catalisadores híbridos Ziegler-Natta/metaloceno na homo- e copolimerização de etileno The performance evaluation of hybrid Ziegler-Natta/metallocene catalysts in homo- and copolymerization of ethylene

    Directory of Open Access Journals (Sweden)

    Fernanda O. V. Cunha

    2000-09-01

    Full Text Available Foram preparados catalisadores híbridos a partir de um catalisador do tipo Ziegler-Natta heterogêneo (MgCl2.TiCl4 e de um metalocênico (CpTiCl3, afim de se obter catalisadores com diferentes tipos de centros ativos. Foi proposta a formação de um novo centro ativo (CpTi(iBuCl2 na face 100 do suporte de MgCl2. Estes catalisadores foram avaliados na síntese de polietileno de alta densidade (PEAD e de polietileno linear de baixa densidade (PELBD, utilizando-se somente trietilalumínio (TEA como cocatalisador. Foi verificada a influência da razão molar Al/Ti, temperatura e tempo de polimerização na produtividade dos catalisadores e nas propriedades dos polímeros obtidos. Os catalisadores mistos apresentaram atividade catalítica da ordem de 5,0 kgPol/g cat.h na polimerização de etileno e da ordem de 7,0 kgPol/g cat.h na copolimerização etileno-1-buteno.Hybrid catalysts formed by a heterogeneous Ziegler-Natta catalyst (MgCl2.TiCl4 and a metallocene (CpTiCl3 were prepared in this work. The formation of a new catalytic species CpTi(iBuCl2 on the (100 MgCl2 face has been proposed. These catalyst systems were applied to synthesize high density polyethylene (HDPE and linear low density polyethylene (LLDPE, using only triethyl aluminium (TEA as a cocatalyst. The influence of Al/Ti molar ratio, temperature and time of polymerization on the catalyst activity and on the polymer properties were evaluated. The catalyst activities were about 5.0 kgPol/g cat.h for ethylene polymerization and 7.0 kgPol/g cat.h for ethylene-1-butene coplymerization.

  16. Respiração, produção de etileno e qualidade de maçãs "Gala" em função do dano mecânico por impacto e da aplicação de 1-metilciclopropeno Respiration, ethylene production and quality of 'Gala' apples in function to impact injury and treatment with 1-methylcyclopropene

    Directory of Open Access Journals (Sweden)

    Cristiano André Steffens

    2008-10-01

    Full Text Available O objetivo deste trabalho foi avaliar o efeito do dano mecânico por impacto e da aplicação de 1-metilciclopropeno sobre a atividade respiratória e a taxa de produção de etileno e a qualidade físico-química de maçãs "Gala", após o armazenamento em atmosfera controlada. Os tratamentos avaliados foram T1: controle; T2: dano mecânico; T3: 1-metilciclopropeno; T4: dano mecânico + 1-metilciclopropeno; e T5: 1-metilciclopropeno + dano mecânico. Após a aplicação dos tratamentos, os frutos foram armazenados sob condição ambiente (20±2°C/65±5% UR. Os frutos submetidos ao dano mecânico e não tratados com 1-metilciclopropeno apresentaram um maior incremento na produção de etileno. O tratamento dano mecânico não aumentou a atividade respiratória e pouco influenciou o amadurecimento dos frutos, comparado ao controle, porém, aumentou a ocorrência de podridões. O 1-metilciclopropeno reduziu o metabolismo e a perda de qualidade dos frutos. Nos frutos submetidos ao dano mecânico, a aplicação de 1-metilciclopropeno reduziu a incidência de podridões.The objective of this research was to evaluate the effect of the impact injury and treatment with 1-methylcyclopropene on respiration and ethylene production rates and on quality of 'Gala' apples after the storage in controlled atmosphere. The treatments evaluated were: T1: control, T2: mechanical injury; T3: 1-methylcyclopropene; T4: mechanical injury + 1-methylcyclopropene; and T5: 1-methylcyclopropene + mechanical injury. Fruits were then left at ambient conditions (20±2°C/65±5% RH. Fruits submitted to mechanical injury, without the treatment with 1-methylcyclopropene, showed the highest increment of ethylene production. The mechanical injury did not increase the respiratory rate and had small effect on fruit ripening, compared to the control treatment, but increased rot incidence. The 1-methylcyclopropene reduced the metabolism and the loss of fruit quality. In fruits

  17. Cherenkov TOF PET with silicon photomultipliers

    Energy Technology Data Exchange (ETDEWEB)

    Dolenec, R., E-mail: rok.dolenec@ijs.si [Faculty of Chemistry and Chemical Engineering, University of Maribor, Maribor (Slovenia); Jožef Stefan Institute, Jamova cesta 39, SI-1000 Ljubljana (Slovenia); Faculty of Mathematics and Physics, University of Ljubljana, Ljubljana (Slovenia); Korpar, S. [Faculty of Chemistry and Chemical Engineering, University of Maribor, Maribor (Slovenia); Jožef Stefan Institute, Jamova cesta 39, SI-1000 Ljubljana (Slovenia); Križan, P. [Faculty of Mathematics and Physics, University of Ljubljana, Ljubljana (Slovenia); Jožef Stefan Institute, Jamova cesta 39, SI-1000 Ljubljana (Slovenia); Pestotnik, R. [Jožef Stefan Institute, Jamova cesta 39, SI-1000 Ljubljana (Slovenia)

    2015-12-21

    As previously demonstrated, an excellent timing resolution below 100 ps FWHM is possible in time-of-flight positron emission tomography (TOF PET) if the detection method is based on the principle of detecting photons of Cherenkov light, produced in a suitable material and detected by microchannel plate photomultipliers (MCP PMTs). In this work, the silicon photomultipliers (SiPMs) were tested for the first time as the photodetectors in Cherenkov TOF PET. The high photon detection efficiency (PDE) of SiPMs led to a large improvement in detection efficiency. On the other hand, the time response of currently available SiPMs is not as good as that of MCP PMTs. The SiPM dark counts introduce a new source of random coincidences in Cherenkov method, which would be overwhelming with present SiPM technology at room temperature. When the apparatus was cooled, its performance significantly improved.

  18. Simplification of Methods for PET Radiopharmaceutical Syntheses

    Energy Technology Data Exchange (ETDEWEB)

    Kilbourn, Michael, R.

    2011-12-27

    In an attempt to develop simplified methods for radiochemical synthesis of radiopharmaceuticals useful in Positron Emission Tomography (PET), current commercially available automated synthesis apparati were evaluated for use with solid phase synthesis, thin-film techniques, microwave-accelerated chemistry, and click chemistry approaches. Using combinations of these techniques, it was shown that these automated synthesis systems can be simply and effectively used to support the synthesis of a wide variety of carbon-11 and fluorine-18 labeled compounds, representing all of the major types of compounds synthesized and using all of the common radiochemical precursors available. These techniques are available for use to deliver clinically useful amounts of PET radiopharmaceuticals with chemical and radiochemical purities and high specific activities, suitable for human administration.

  19. Quantitative carotid PET/MR imaging: clinical evaluation of MR-Attenuation correction versus CT-Attenuation correction in (18)F-FDG PET/MR emission data and comparison to PET/CT.

    Science.gov (United States)

    Bini, Jason; Robson, Philip M; Calcagno, Claudia; Eldib, Mootaz; Fayad, Zahi A

    2015-01-01

    Current PET/MR systems employ segmentation of MR images and subsequent assignment of empirical attenuation coefficients for quantitative PET reconstruction. In this study we examine the differences in the quantification of (18)F-FDG uptake in the carotid arteries between PET/MR and PET/CT scanners. Five comparisons were performed to asses differences in PET quantification: i) PET/MR MR-based AC (MRAC) versus PET/MR CTAC, ii) PET/MR MRAC versus PET/CT, iii) PET/MR MRAC with carotid coil versus PET/MR MRAC without coil, iv) PET/MR MRAC scan 2 versus PET/MR MRAC scan 1, and v) PET/MR CTAC versus PET/CT. Standardized uptakes values (SUV) mean and SUV maximum were calculated for six regions-of-interests: left and right carotid arteries, left and right lungs, spine and muscle. Pearson's Correlation and Bland-Altman plots were used to compare SUV mean and maximum within each ROI of each patient. PET/MR emission data reconstructed with MRAC versus PET/MR emission data reconstructed with CTAC had percent differences of SUV mean ranging from -2.0% (Absolute Difference, -0.02) to 7.4% (absolute difference, 0.06). Percent differences within the carotid arteries proved to correlate well with differences of SUV mean of 5.4% (Absolute Difference, 0.07) in the left carotid and 2.7% (Absolute Difference, 0.03) in the right carotid. Pearson's correlation and Bland-Altman of PET/MR with MRAC versus PET/MR with CTAC showed high correlation between SUV mean (R(2)=0.80, mean difference 0.03 ± 0.18 SUV, p=0.3382), demonstrating excellent correlation within ROIs analyzed. The results of this study support the use of (18)F-FDG PET/MR for quantitative measure of inflammation in the carotid arteries.

  20. Quantitative carotid PET/MR imaging: clinical evaluation of MR-Attenuation correction versus CT-Attenuation correction in 18F-FDG PET/MR emission data and comparison to PET/CT

    Science.gov (United States)

    Bini, Jason; Robson, Philip M; Calcagno, Claudia; Eldib, Mootaz; Fayad, Zahi A

    2015-01-01

    Current PET/MR systems employ segmentation of MR images and subsequent assignment of empirical attenuation coefficients for quantitative PET reconstruction. In this study we examine the differences in the quantification of 18F-FDG uptake in the carotid arteries between PET/MR and PET/CT scanners. Five comparisons were performed to asses differences in PET quantification: i) PET/MR MR-based AC (MRAC) versus PET/MR CTAC, ii) PET/MR MRAC versus PET/CT, iii) PET/MR MRAC with carotid coil versus PET/MR MRAC without coil, iv) PET/MR MRAC scan 2 versus PET/MR MRAC scan 1, and v) PET/MR CTAC versus PET/CT. Standardized uptakes values (SUV) mean and SUV maximum were calculated for six regions-of-interests: left and right carotid arteries, left and right lungs, spine and muscle. Pearson’s Correlation and Bland-Altman plots were used to compare SUV mean and maximum within each ROI of each patient. PET/MR emission data reconstructed with MRAC versus PET/MR emission data reconstructed with CTAC had percent differences of SUV mean ranging from -2.0% (Absolute Difference, -0.02) to 7.4% (absolute difference, 0.06). Percent differences within the carotid arteries proved to correlate well with differences of SUV mean of 5.4% (Absolute Difference, 0.07) in the left carotid and 2.7% (Absolute Difference, 0.03) in the right carotid. Pearson’s correlation and Bland-Altman of PET/MR with MRAC versus PET/MR with CTAC showed high correlation between SUV mean (R2=0.80, mean difference 0.03 ± 0.18 SUV, p=0.3382), demonstrating excellent correlation within ROIs analyzed. The results of this study support the use of 18F-FDG PET/MR for quantitative measure of inflammation in the carotid arteries. PMID:26069863

  1. Associations of Pet Ownership with Older Adults Eating Patterns and Health

    National Research Council Canada - National Science Library

    Roschelle Heuberger

    2017-01-01

      Pet ownership has been shown to improve quality of life for older adults. The objective of this cross-sectional study was to compare older pet owners and older non-pet owners and assess differences between groups...

  2. 24 CFR 5.363 - Housing programs: Protection of the pet.

    Science.gov (United States)

    2010-04-01

    ... and Urban Development GENERAL HUD PROGRAM REQUIREMENTS; WAIVERS Pet Ownership for the Elderly or Persons With Disabilities Pet Ownership Requirements for Housing Programs § 5.363 Housing programs... rules. Pet Ownership Requirements for Public Housing Programs ...

  3. VII. Boettstein Colloquium: PET-Radiopharmaceuticals at PSI: achievement and future prospects

    Energy Technology Data Exchange (ETDEWEB)

    Schubiger, P.A.; Beer, H.F.; Blaeuenstein, P.; Leenders, K.E.

    1993-12-31

    The three sessions of the 1993 Boettstein colloquium dealt with the following topics: - PET-radiopharmaceuticals, - PET-scanning: significance of tracer uptake, - clinical options using PET. 22 papers were presented. figs., refs.

  4. Amyloid PET in pseudotumoral multiple sclerosis.

    Science.gov (United States)

    Matías-Guiu, Jordi A; Cabrera-Martín, María Nieves; Cortés-Martínez, Ana; Pytel, Vanesa; Moreno-Ramos, Teresa; Oreja-Guevara, Celia; Carreras, José Luis; Matías-Guiu, Jorge

    2017-07-01

    Pseudotumoral multiple sclerosis is a rare form of demyelinating disease of the central nervous system. Positron emission tomography (PET) using amyloid-tracers has also been suggested as a marker of damage in white matter lesions in multiple sclerosis due to the nonspecific uptake of these tracers in white matter. We present the case of a 59 year-old woman with a pathological-confirmed pseudotumoral multiple sclerosis, who was studied with the amyloid tracer (18)F-florbetaben. The patient had developed word-finding difficulties and right hemianopia twelve years ago. In that time, MRI showed a lesion on the left hemisphere with an infiltrating aspect in frontotemporal lobes. Brain biopsy showed demyelinating areas and inflammation. During the following years, two new clinical relapses occurred. (18)F-florbetaben PET showed lower uptake in the white matter lesion visualized in the CT and MRI images. Decreased tracer uptake was also observed in a larger area of the left hemisphere beyond the lesions observed on MRI or CT. White matter lesion volume on FLAIR was 44.2mL, and tracer uptake change between damaged white matter and normal appearing white matter was - 40.5%. Standardized uptake value was inferior in the pseudotumoral lesion than in the other white matter lesions. We report the findings of amyloid PET in a patient with pseudotumoral multiple sclerosis. This case provides further evidence on the role of amyloid PET in the assessment of white matter and demyelinating diseases. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. Immuno-PET for Clinical Theranostic Approaches

    OpenAIRE

    Clément Bailly; Pierre-François Cléry; Alain Faivre-Chauvet; Mickael Bourgeois; François Guérard; Ferid Haddad; Jacques Barbet; Michel Chérel; Françoise Kraeber-Bodéré; Thomas Carlier; Caroline Bodet-Milin

    2016-01-01

    International audience; Recent advances in molecular characterization of tumors have allowed identification of new molecular targets on tumor cells or biomarkers. In medical practice, the identification of these biomarkers slowly but surely becomes a prerequisite before any treatment decision, leading to the concept of personalized medicine. Immuno-positron emission tomography (PET) fits perfectly with this approach. Indeed, monoclonal antibodies (mAbs) labelled with radionuclides represent p...

  6. Bacterial and parasitic diseases of pet fish.

    Science.gov (United States)

    Roberts, Helen E; Palmeiro, Brian; Weber, E Scott

    2009-09-01

    Bacterial and parasitic diseases are very common problems in pet fish. Diagnostic testing for bacterial and parasitic diseases is simple to do; many tests can be done on ambulatory visits. When logical treatment strategies are initiated and supported by diagnostic testing, a successful outcome is possible. Identification of the correct pathogens also allows an educational opportunity for discussions on prevention and biosecurity practices with clients and although fish are poikilothermic, there are some bacterial and parasitic pathogens that are zoonotic.

  7. The application of PET imaging in psychoneuroimmunology research.

    Science.gov (United States)

    Hannestad, Jonas

    2012-01-01

    Positron emission tomography (PET) imaging is a research tool that allows in vivo measurements of brain metabolism and specific target molecules. PET imaging can be used to measure these brain variables in a variety of species, including human and non-human primates, and rodents. PET imaging can therefore be combined with various experimental and clinical model systems that are commonly used in psychoneuroimmunology research.

  8. Structural insight into catalytic mechanism of PET hydrolase

    OpenAIRE

    Han, Xu; Liu, Weidong; Huang, Jian-Wen; Ma, Jiantao; Zheng, Yingying; Ko, Tzu-Ping; Xu, Limin; Cheng, Ya-Shan; Chen, Chun-Chi; Guo, Rey-Ting

    2017-01-01

    PET hydrolase (PETase), which hydrolyzes polyethylene terephthalate (PET) into soluble building blocks, provides an attractive avenue for the bioconversion of plastics. Here we present the structures of a novel PETase from the PET-consuming microbe Ideonella sakaiensis in complex with substrate and product analogs. Through structural analyses, mutagenesis, and activity measurements, a substrate-binding mode is proposed, and several features critical for catalysis are elucidated.

  9. Structural insight into catalytic mechanism of PET hydrolase.

    Science.gov (United States)

    Han, Xu; Liu, Weidong; Huang, Jian-Wen; Ma, Jiantao; Zheng, Yingying; Ko, Tzu-Ping; Xu, Limin; Cheng, Ya-Shan; Chen, Chun-Chi; Guo, Rey-Ting

    2017-12-13

    PET hydrolase (PETase), which hydrolyzes polyethylene terephthalate (PET) into soluble building blocks, provides an attractive avenue for the bioconversion of plastics. Here we present the structures of a novel PETase from the PET-consuming microbe Ideonella sakaiensis in complex with substrate and product analogs. Through structural analyses, mutagenesis, and activity measurements, a substrate-binding mode is proposed, and several features critical for catalysis are elucidated.

  10. Reproducibility of Quantitative Brain Imaging Using a PET-Only and a Combined PET/MR System

    Directory of Open Access Journals (Sweden)

    Martin L. Lassen

    2017-07-01

    Full Text Available The purpose of this study was to test the feasibility of migrating a quantitative brain imaging protocol from a positron emission tomography (PET-only system to an integrated PET/MR system. Potential differences in both absolute radiotracer concentration as well as in the derived kinetic parameters as a function of PET system choice have been investigated. Five healthy volunteers underwent dynamic (R-[11C]verapamil imaging on the same day using a GE-Advance (PET-only and a Siemens Biograph mMR system (PET/MR. PET-emission data were reconstructed using a transmission-based attenuation correction (AC map (PET-only, whereas a standard MR-DIXON as well as a low-dose CT AC map was applied to PET/MR emission data. Kinetic modeling based on arterial blood sampling was performed using a 1-tissue-2-rate constant compartment model, yielding kinetic parameters (K1 and k2 and distribution volume (VT. Differences for parametric values obtained in the PET-only and the PET/MR systems were analyzed using a 2-way Analysis of Variance (ANOVA. Comparison of DIXON-based AC (PET/MR with emission data derived from the PET-only system revealed average inter-system differences of −33 ± 14% (p < 0.05 for the K1 parameter and −19 ± 9% (p < 0.05 for k2. Using a CT-based AC for PET/MR resulted in slightly lower systematic differences of −16 ± 18% for K1 and −9 ± 10% for k2. The average differences in VT were −18 ± 10% (p < 0.05 for DIXON- and −8 ± 13% for CT-based AC. Significant systematic differences were observed for kinetic parameters derived from emission data obtained from PET/MR and PET-only imaging due to different standard AC methods employed. Therefore, a transfer of imaging protocols from PET-only to PET/MR systems is not straightforward without application of proper correction methods.Clinical Trial Registration:www.clinicaltrialsregister.eu, identifier 2013-001724-19

  11. Reliability of semiquantitative {sup 18}F-FDG PET parameters derived from simultaneous brain PET/MRI: A feasibility study

    Energy Technology Data Exchange (ETDEWEB)

    Jena, Amarnath, E-mail: drjena2002@yahoo.com [Department of Molecular Imaging and Nuclear Medicine, Indraprastha Apollo Hospitals, Sarita Vihar, Mathura Road, New Delhi 110076, Delhi (India); Taneja, Sangeeta, E-mail: s_taneja1974@yahoo.com [Department of Molecular Imaging and Nuclear Medicine, Indraprastha Apollo Hospitals, Sarita Vihar, Mathura Road, New Delhi 110076, Delhi (India); Goel, Reema, E-mail: reemagoell@gmail.com [Department of Molecular Imaging and Nuclear Medicine, Indraprastha Apollo Hospitals, Sarita Vihar, Mathura Road, New Delhi 110076, Delhi (India); Renjen, Pushpendranath, E-mail: pnrenjen@hotmail.com [Department of Neurology, Indraprastha Apollo Hospitals, Sarita Vihar, Mathura Road, New Delhi 110076, Delhi (India); Negi, Pradeep, E-mail: pradeepmri@rediffmail.com [Department of Molecular Imaging and Nuclear Medicine, Indraprastha Apollo Hospitals, Sarita Vihar, Mathura Road, New Delhi 110076, Delhi (India)

    2014-07-15

    Purpose: Simultaneous brain PET/MRI faces an important issue of validation of accurate MRI based attenuation correction (AC) method for precise quantitation of brain PET data unlike in PET/CT systems where the use of standard, validated CT based AC is routinely available. The aim of this study was to investigate the feasibility of evaluation of semiquantitative {sup 18}F-FDG PET parameters derived from simultaneous brain PET/MRI using ultrashort echo time (UTE) sequences for AC and to assess their agreement with those obtained from PET/CT examination. Methods: Sixteen patients (age range 18–73 years; mean age 49.43 (19.3) years; 13 men 3 women) underwent simultaneous brain PET/MRI followed immediately by PET/CT. Quantitative analysis of brain PET images obtained from both studies was undertaken using Scenium v.1 brain analysis software package. Twenty ROIs for various brain regions were system generated and 6 semiquantitative parameters including maximum standardized uptake value (SUV max), SUV mean, minimum SUV (SUV min), minimum standard deviation (SD min), maximum SD (SD max) and SD from mean were calculated for both sets of PET data for each patient. Intra-class correlation coefficients (ICCs) were determined to assess agreement between the various semiquantitative parameters for the two PET data sets. Results: Intra-class co-relation between the two PET data sets for SUV max, SUV mean and SD max was highly significant (p < 0.00) for all the 20 predefined brain regions with ICC > 0.9. SD from mean was also found to be statistically significant for all the predefined brain regions with ICC > 0.8. However, SUV max and SUV mean values obtained from PET/MRI were significantly lower compared to those of PET/CT for all the predefined brain regions. Conclusion: PET quantitation accuracy using the MRI based UTE sequences for AC in simultaneous brain PET/MRI is reliable in a clinical setting, being similar to that obtained using PET/CT.

  12. Gamma-camera 18F-FDG PET in diagnosis and staging of patients presenting with suspected lung cancer and comparison with dedicated PET

    DEFF Research Database (Denmark)

    Oturai, Peter S; Mortensen, Jann; Enevoldsen, Henriette

    2004-01-01

    It is not clear whether high-quality coincidence gamma-PET (gPET) cameras can provide clinical data comparable with data obtained with dedicated PET (dPET) cameras in the primary diagnostic work-up of patients with suspected lung cancer. This study focuses on 2 main issues: direct comparison betw...

  13. Dual tracer functional imaging of gastroenteropancreatic neuroendocrine tumors using 68Ga-DOTA-NOC PET-CT and 18F-FDG PET-CT: competitive or complimentary?

    Science.gov (United States)

    Naswa, Niraj; Sharma, Punit; Gupta, Santosh Kumar; Karunanithi, Sellam; Reddy, Rama Mohan; Patnecha, Manish; Lata, Sneh; Kumar, Rakesh; Malhotra, Arun; Bal, Chandrasekhar

    2014-01-01

    This study aimed to compare the diagnostic performance of Ga-DOTANOC PET/CT with F-FDG PET/CT in the patients with gastroenteropancreatic neuroendocrine tumors (GEP-NETs). Data of 51 patients with definite histological diagnosis of GEP-NET who underwent both Ga-DOTA-NOC PET-CT and F-FDG PET-CT within a span of 15 days were selected for this retrospective analysis. Sensitivity, specificity, and predictive values were calculated for Ga-DOTA-NOC PET-CT and F-FDG PET-CT, and results were compared both on patientwise and regionwise analysis. Ga-DOTA-NOC PET-CT is superior to F-FDG PET-CT on patientwise analysis (P NOC PET-CT is superior to F-FDG PET-CT only for lymph node metastases (P NOC PET-CT detected more liver and skeletal lesions compared with F-FDG PET-CT, the difference was not statistically significant. In addition, the results of combined imaging helped in selecting candidates who would undergo the appropriate mode of treatment, whether octreotide therapy or conventional chemotherapy Ga-DOTA-NOC PET-CT seems to be superior to F-FDG PET-CT for imaging GEP-NETs. However, their role seems to be complementary because combination of Ga-DOTA-NOC PET-CT and F-FDG PET-CT in such patients helps demonstrate the total disease burden and segregate them to proper therapeutic groups.

  14. PET imaging of the autonomic nervous system.

    Science.gov (United States)

    Thackeray, James T; Bengel, Frank M

    2016-12-01

    The autonomic nervous system is the primary extrinsic control of heart rate and contractility, and is subject to adaptive and maladaptive changes in cardiovascular disease. Consequently, noninvasive assessment of neuronal activity and function is an attractive target for molecular imaging. A myriad of targeted radiotracers have been developed over the last 25 years for imaging various components of the sympathetic and parasympathetic signal cascades. While routine clinical use remains somewhat limited, a number of larger scale studies in recent years have supplied momentum to molecular imaging of autonomic signaling. Specifically, the findings of the ADMIRE HF trial directly led to United States Food and Drug Administration approval of 123I-metaiodobenzylguanidine (MIBG) for Single Photon Emission Computed Tomography (SPECT) assessment of sympathetic neuronal innervation, and comparable results have been reported using the analogous PET agent 11C-meta-hydroxyephedrine (HED). Due to the inherent capacity for dynamic quantification and higher spatial resolution, regional analysis may be better served by PET. In addition, preliminary clinical and extensive preclinical experience has provided a broad foundation of cardiovascular applications for PET imaging of the autonomic nervous system. Recent years have witnessed the growth of novel quantification techniques, expansion of multiple tracer studies, and improved understanding of the uptake of different radiotracers, such that the transitional biology of dysfunctional subcellular catecholamine handling can be distinguished from complete denervation. As a result, sympathetic neuronal molecular imaging is poised to play a role in individualized patient care, by stratifying cardiovascular risk, visualizing underlying biology, and guiding and monitoring therapy.

  15. Surface structure of oriented PET films

    CERN Document Server

    Kirov, K

    2001-01-01

    crystallinity and the level of molecular orientation of the polymer are highest at the film surface and gradually decrease away from it. The same trend for an increase in structural order nearer the film surface was observed in a series of PET films drawn uniaxially in laboratory conditions. The observed strong dependence of stratification in the oriented films on drawing ratio, lead to the conclusion, that the structural gradients arise as a result of viscous flow. The molecular mechanism of stratification is discussed and leads to the idea of enhanced chain mobility at the PET film surface. The idea is in line with recent studies showing a depression of the glass transition temperature of free polymer surfaces. In addition, the results on structure formation in PET films during drawing, give support to the existing view that polymer crystallisation is assisted by a spinodal-decomposition nucleation process. Polymer films are widely used as substrates in nano-composite materials and therefore have to possess...

  16. Bereavement following death of a pet.

    Science.gov (United States)

    Archer, J; Winchester, G

    1994-05-01

    A 40-item questionnaire based on reactions following human bereavement was used to investigate the occurrence of grief following death of a pet in a sample of 88 people. Items indicating initial numbness or disbelief, preoccupation with the loss, a loss of part of themselves and being drawn towards reminders were endorsed by half to four-fifths of the sample. About a quarter reported the urge to search, avoidance or mitigation strategies, anger, anxiety and depression. The questionnaire showed high internal reliability, and total scores were significantly positively correlated with the degree of affective attachment to the pet, the suddenness of the death and whether the respondent lived alone; but not with the type of pet, the time since it had died, and how long the owner had been with it. Factor analysis of the questionnaire revealed one main factor accounting for about a third of the variance, described as emotional distress associated with the loss; two lesser factors involved items representing personal importance of the loss and a feeling of continued attachment. Overall these findings indicate a parallel reaction to that following a human bereavement, but with a lower frequency of affective distress. Moderator variables were also comparable with those known to be important for grief following a human loss.

  17. Compton scatter tomography in TOF-PET

    Science.gov (United States)

    Hemmati, Hamidreza; Kamali-Asl, Alireza; Ay, Mohammadreza; Ghafarian, Pardis

    2017-10-01

    Scatter coincidences contain hidden information about the activity distribution on the positron emission tomography (PET) imaging system. However, in conventional reconstruction, the scattered data cause the blurring of images and thus are estimated and subtracted from detected coincidences. List mode format provides a new aspect to use time of flight (TOF) and energy information of each coincidence in the reconstruction process. In this study, a novel approach is proposed to reconstruct activity distribution using the scattered data in the PET system. For each single scattering coincidence, a scattering angle can be determined by the recorded energy of the detected photons, and then possible locations of scattering can be calculated based on the scattering angle. Geometry equations show that these sites lie on two arcs in 2D mode or the surface of a prolate spheroid in 3D mode, passing through the pair of detector elements. The proposed method uses a novel and flexible technique to estimate source origin locations from the possible scattering locations, using the TOF information. Evaluations were based on a Monte-Carlo simulation of uniform and non-uniform phantoms at different resolutions of time and detector energy. The results show that although the energy uncertainties deteriorate the image spatial resolution in the proposed method, the time resolution has more impact on image quality than the energy resolution. With progress of the TOF system, the reconstruction using the scattered data can be used in a complementary manner, or to improve image quality in the next generation of PET systems.

  18. SPECT and PET Imaging of Meningiomas

    Directory of Open Access Journals (Sweden)

    Varvara Valotassiou

    2012-01-01

    Full Text Available Meningiomas arise from the meningothelial cells of the arachnoid membranes. They are the most common primary intracranial neoplasms and represent about 20% of all intracranial tumors. They are usually diagnosed after the third decade of life and they are more frequent in women than in men. According to the World Health Organization (WHO criteria, meningiomas can be classified into grade I meningiomas, which are benign, grade II (atypical and grade III (anaplastic meningiomas, which have a much more aggressive clinical behaviour. Computed Tomography (CT and Magnetic Resonance Imaging (MRI are routinely used in the diagnostic workup of patients with meningiomas. Molecular Nuclear Medicine Imaging with Single Photon Emission Computed Tomography (SPECT and Positron Emission Tomography (PET could provide complementary information to CT and MRI. Various SPECT and PET tracers may provide information about cellular processes and biological characteristics of meningiomas. Therefore, SPECT and PET imaging could be used for the preoperative noninvasive diagnosis and differential diagnosis of meningiomas, prediction of tumor grade and tumor recurrence, response to treatment, target volume delineation for radiation therapy planning, and distinction between residual or recurrent tumour from scar tissue.

  19. Pet (dog and cat) overpopulation in the United States.

    Science.gov (United States)

    Olson, P N; Moulton, C

    1993-01-01

    Over half of all United States (US) households own a dog or cat. The veterinary profession can now provide health care for dogs and cats of affluent or devoted owners that rivals the health care offered many human patients. Unfortunately, as many pets receive medical and surgical care that becomes increasingly sophisticated, other pets in the US receive no veterinary care at all. Additionally, millions of pets are humanely killed in US animal shelters because owners are not committed to the continual responsibilities of pet care. Although the total dog and cat population is unknown in the US, as is the total number of pets killed, estimates suggest that between one-tenth and one-quarter of the entire US pet population is destroyed annually because of a surplus dog and cat problem. Pet overpopulation is attributable to relinquishment and abandonment, as well as to birth rates; thus, veterinarians must strive to reduce pet overpopulation by not only curbing reproduction, but also by decreasing the major cause of pet death in the US (i.e. humane killing). Thus, the veterinary profession must take a prominent role in the campaign to prevent the deaths of healthy animals for whom homes cannot be found, just as it has done to prevent the deaths of sick animals that do have homes.

  20. PET protection optimization for streaming scalable videos with multiple transmissions.

    Science.gov (United States)

    Xiong, Ruiqin; Taubman, David S; Sivaraman, Vijay

    2013-11-01

    This paper investigates priority encoding transmission (PET) protection for streaming scalably compressed video streams over erasure channels, for the scenarios where a small number of retransmissions are allowed. In principle, the optimal protection depends not only on the importance of each stream element, but also on the expected channel behavior. By formulating a collection of hypotheses concerning its own behavior in future transmissions, limited-retransmission PET (LR-PET) effectively constructs channel codes spanning multiple transmission slots and thus offers better protection efficiency than the original PET. As the number of transmission opportunities increases, the optimization for LR-PET becomes very challenging because the number of hypothetical retransmission paths increases exponentially. As a key contribution, this paper develops a method to derive the effective recovery-probability versus redundancy-rate characteristic for the LR-PET procedure with any number of transmission opportunities. This significantly accelerates the protection assignment procedure in the original LR-PET with only two transmissions, and also makes a quick and optimal protection assignment feasible for scenarios where more transmissions are possible. This paper also gives a concrete proof to the redundancy embedding property of the channel codes formed by LR-PET, which allows for a decoupled optimization for sequentially dependent source elements with convex utility-length characteristic. This essentially justifies the source-independent construction of the protection convex hull for LR-PET.