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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
161

Processos patológicos em linfonodos na espécie canina: revisão de literatura / Pathologic processes in canine lymph nodes: literature review

Baldani, Laerte Aleixo 07 March 2006 (has links)
Os linfonodos podem ser compreendidos como estruturas integrantes de dois sistemas orgânicos, o circulatório e o imunológico, apresentando estrutura mutável decorrente do tipo, da intensidade e do tempo da estimulação antigênica. As doenças nodais são complexas devido ao grande número de agentes que atingem os linfonodos via linfa e por causa da complexidade inerente do sistema imunológico e suas doenças próprias. A linfadenopatia é um achado clínico muito comum em cães, e o seu significado não deve ser desprezado. Inúmeros processos patológicos são observados no linfonodo canino, particularmente as hiperplasias reacionais benignas, linfadenites e os linfomas, e a sua total compreenção requer o conhecimento de histofisiologia, noções de imunologia, e biologia molecular. O conhecimento dos métodos diagnósticos disponíveis tem fundamental importância para o manejo do paciente, permitindo um tratamento acurado e eficiente / The lymph nodes may be known as integrants of two organic systems, circulatory and immunological, demonstrating mutable structure depending on the type, intensity, and time of antigenic stimulation. Nodal diseases are complex, because of the large number of diseases reaching nodes via lymph and because of the inherent complexity of the immune system and its own diseases. Lymphadenopathy is a common clinical finding, Many pathological processes has been found in canine lymph nodes, primarily benign reative hiperplasia, lymphadenitis and lymphomas, and your complete comprehension requires knowledge in histophysiology, immunology notions, and molecular biology. An understanding of the available diagnostic methods has fundamental importance for patient management, allowing an accurate and efficient treatment
162

Vascularização arterial da região do nó sinoatrial em corações humanos normais / Arterial vascularization of the sinoatrial node area in normal human hearts

Vidotti, Ana Paula 19 December 2006 (has links)
O nó sinoatrial (NSA) é responsável pela geração dos impulsos nervosos determinantes da contração cardíaca, sendo seu suprimento sangüíneo feito pela artéria do nó sinoatrial - ANSA. Neste trabalho, objetivou-se estudar a vascularização arterial da região do NSA, em corações humanos normais, por meio de técnicas macroscópicas, procurando enfocar a terminação da ANSA, sua origem e trajeto, atentando para a presença ou não da chamada "rede arterial perisinusal". Vinte e cinco (25) corações, de indivíduos adultos, de ambos os sexos, sem doenças cardíacas, obtidos no "Serviço de Verificação de Óbitos da Capital (SVOC) da Universidade de São Paulo", tiveram os óstios coronários canulados para injeção de resina vinílica corada. As peças foram fixadas em solução aquosa de formol 10% (48 horas), seguindo-se a dissecação da circulação atrial. As metades direita e esquerda dos átrios apresentaram número equivalente de artérias (62 e 63, respectivamente), o que não ocorreu para as metades anterior e posterior (77 e 48, respectivamente). A ANSA originou-se da artéria coronária direita, em 15 casos (60%): em onze (11) da artéria atrial direita anterior medial (AADAM), dois (2) da direita intermédia (AADAI) e dois (2) da direita lateral (AADAL). Em oito casos (32%), originava-se da artéria coronária esquerda: três (3) da artéria atrial esquerda posterior lateral (AASPL), dois (2) da esquerda anterior intermédia (AASAI) e três (3) da anterior medial (AASAM). Em 8% dos casos (2) a distribuição era peculiar - em um AASAM e artéria atrial esquerda anterior lateral (AASAL) estavam em continuidade, até alcançarem e penetrarem a região do nó, e, no segundo caso, a AASAM unia-se com a artéria atrial direita posterior lateral (AADPL), com trajeto em forma "U", circundando a base da veia cava superior. Em oito corações, identificou-se intensa ramificação na região perinodal, indicativo da ocorrência da "rede arterial perisinusal". A diversidade do trajeto da ANSA ora observada e a indicada pela literatura reitera a necessidade de maiores estudos sobre este trajeto, de modo a contribuir para a higidez do NSA nas cirurgias envolvendo manipulação atrial. / The sinoatrial node (NSA) is responsible for the production of the nervous impulses, which determine the cardiac contraction and its blood supply is provided by the sinoatrial node artery - ANSA. In this research we aimed to study the arterial vascularization of the NSA area in normal human hearts, with macroscopic techniques intending to identify the origin of the sinoatrial node artery, its termination, attempting to the presence or not of the so called "arterial perisinusal network". Twenty five (25) hearts, without diseases, obtained from the "Serviço de Verificação de Óbitos da Capital (SVOC) da Universidade de São Paulo" were canulated by the coronary ostium following injected with colored resin. They were fixed in 10% watery formaldehyde solution (48 hours) an afterwards the atrial circulation was dissected. The left and right atrial halves demonstrating equivalence of arteries (62 and 63 respectively), which was not observed in the anterior and posterior halves of the heart (77 and 48 arteries respectively). The ANSA was originated from de right coronary artery in fifteen cases (60%): eleven by the right anterior medial atrial artery (AADAM), two by the right anterior intermedial atrial artery (AADAI) and two by the right anterior lateral atrial artery (AADAL). In eight cases (32%) was originated from the left coronary artery: three by the left posterior lateral atrial artery (AASPL), two by the left anterior intermedial atrial artery (AASAI) and three by left anterior medial atrial artery (AASAM). In 8% of the cases, the vascular distribution was peculiar - in one of them, the AASAM and left anterior lateral atrial artery (AASAL) were in continuous, reaching and penetrating the node area. In the second case, the AASAM artery joined to the right posterior lateral atrial artery (AADPL) forming a continuous "U" shape surrounding the base of the VCS. In eight hearts, the arterial distribution showed intense ramification in the perinodal area, which could indicate the occurrence of the "perisinusal arterial network". The diversity of the ANSA´s traject, indicated by the literature, shows the necessarily others studies about it to contribute to the integrity of the NSA in surgical procedures that involves the atrial walls.
163

Assembly and maintenance of the node of Ranvier

Brivio, Veronica January 2015 (has links)
Myelination of axons in the central and peripheral nervous system (CNS and PNS) is required for saltatory propagation of nerve impulses. Myelinated axons are organized in functionally distinct membrane domains and the correct formation and maintenance of these domains is fundamental for the correct propagation of the electrical impulse; however, the underlying mechanisms by which these domains are specified are just starting to be unravelled. The paranodal junctions (PNJs) have been shown to contribute to node formation in the CNS and to domain maintenance both in the CNS and PNS. In this thesis I have studied the function of the linkage of the PNJs to the axonal cytoskeleton in regulating these processes by using a combination of knock out and transgenic rescue strategies. Further, I have initiated studies on the live imaging of node assembly. I have shown that the link between the PNJ and the axonal cytoskeleton is required for both the correct timing of oligodendrocyte process migration and for clustering nodal proteins at heminodes, before nodes of Ranvier are formed. Failure to correctly regulate these events during development results in shorter internodes in adults. Further, I have shown the importance of the axonal paranodal cytoskeleton in the maintenance of the node of Ranvier, both in CNS and PNS. In the absence of a link between the PNJ and the axonal cytoskeleton, paranodes disassemble, which causes disruption of both nodal and juxtaparanodal domains. Electron microscopy shows that, despite paranodal disruption, transverse bands are preserved when the anchorage of the PNJ to the axonal cytoskeleton is removed. Surprisingly, the preservation of these structures is associated with the amelioration of the neurological defects seen in mice lacking PNJs. In order to study nodal assembly, I have initiated studies on the transport of the nodal proteins Neurofascin186 and β1Nav tagged with fluorescent tags in transgenic mice, in order to analyse axonal transport during development. I have exploited the triangularis muscle explant preparation and have analysed transport of nodal proteins in young and adult mice. I have shown that transport speeds decrease with age and that the two proteins are transported at different speeds in young animals, but these differences do not persist in adults. This suggests that during myelination these proteins are transported in different vesicles and that this may change during development.
164

Injeção intraoperatória de dextran-500-99m tecnécio para identificação do linfonodo sentinela em câncer de mama

Delazeri, Gerson Jacob January 2010 (has links)
Objetivos: Avaliar a eficácia da injeção intraoperatória para identificação do linfonodo sentinela (LS) em câncer de mama com o uso do Dextran 500-99m-Tecnécio (Tc) e azul patente. Analisar se as doses do radiofármaco, o IMC (índice de massa corporal) e o volume da mama influenciam no tempo para migração ao LS. Metodologia: Estudo prospectivo, realizado entre abril de 2008 e junho de 2009, que incluiu 74 biópsias de LS em pacientes com câncer de mama em estádios T1N0 e T2N0. Injetou-se, após indução anestésica, de 0,5 a 1,5 mCi de Dextran 500-99m-Tc filtrado 0,22 μm na região subareolar num volume de 5 ml e 2 ml de azul patente. Resultados: Identificou-se o LS em 100% dos casos. Um LS (1,35%) estava marcado apenas com o azul patente. A taxa de identificação com o “probe” foi de 98% (73/74 casos). A dose média de radiofármaco aplicada foi 0,97 mCi + 0,22. O tempo médio para marcação do LS foi de 10,7 minutos (+ 5,7min). Identificamos em média 1,66 LS com o radioisótopo. A dose aplicada não apresentou relação com o tempo para captação (p=0,73). Quanto maior o volume da mama e IMC, maior o tempo para captação na região axilar (Pearson Correlation r=0,393 p<0,01; r=0,469 p<0,01 - respectivamente). Conclusão: A injeção intraoperatória do radiofármaco é eficaz para identificação do LS em câncer de mama. O tempo para marcação do LS é maior em pacientes com IMC elevado e mamas volumosas. Doses maiores de radiofármaco não diminuem o tempo de migração. / Objectives: To determine the identification of sentinel lymph node (SLN) in breast cancer after intraoperative injection of Dextran 500‐99mTechnetium (Tc) and blue dye. To analyze if the doses of the radioisotope, body mass index (BMI) and breast volume influence the migration time of the SLN. Methodology: Prospective study between april 2008 and june 2009, which included 74 biopsies of SLN in patients with breast cancer in stages T1N0 and T2N0. Intraoperative injection after induction of general anesthesia, 0.5 to 1.5 mCi of dextran 500‐99m‐Tc filtered 0.22 μm in the subareolar region in a volume of 5 ml and 2 ml of blue dye. Results: We identified the SLN in 100% of cases. In one case (1.35%) the SLN was marked only with the blue dye. The SLN identification rate with the probe was 98% (73/74 cases). The mean dose of radioisotope injected was 0.97 + 0.22 mCi. The average time to mark the SLN was 10.7 minutes (+ 5.7 min). We identified an average 1.66 SLN with the radioisotope. The dose had no effect on the time to capture (p = 0.73). The larger breast volume and BMI, the greater the capture time in the axillary region (Pearson Correlation r=0.393 p <0.01, r=0.469 p <0.01 - respectively). Conclusion: Intraoperative injection of the radioisotope is effective for the identification the SLN in breast cancer. Time to mark the SLN is higher in patients with high BMI and large breasts. Higher doses of radioisotope do not decrease the migration time.
165

Análise de arritmias cardíacas no pós operatório tardio de conexão anômala total de veias pulmonares

Tukamoto, Danielle Lilia Dantas 12 June 2015 (has links)
Submitted by Natalia Vieira (natalia.vieira@famerp.br) on 2016-05-20T17:54:02Z No. of bitstreams: 1 danielleliliadantastukamoto_dissert.pdf: 6750015 bytes, checksum: a409b5df80783b77a0948c423b3fbcb5 (MD5) / Made available in DSpace on 2016-05-20T17:54:02Z (GMT). No. of bitstreams: 1 danielleliliadantastukamoto_dissert.pdf: 6750015 bytes, checksum: a409b5df80783b77a0948c423b3fbcb5 (MD5) Previous issue date: 2015-06-12 / Introduction: The frequency of events of total anomalous pulmonary venous connection (TAPVC) varies in the different series from 5.9 to 7.1 / 100 000 live births, representing 1 to 5% of cases of congenital heart disease. Since the current care has developed; the need to approach possible late complications, such as arrhythmias, is important. Objective: To evaluate the distribution of arrhythmias and possible related variables in patients in the late postoperative TAPVC. Method: Medical record review and clinical and noninvasive arrhythmia evaluation were used for data analysis of 20 patients who underwent isolated TAPVC. Statistical analysis for the detection of related variables. Results: Clinical and echocardiographic evaluations showed no significant changes. Of the 20 patients, 13 (65%) showed some abnormalities for age according to the 12-led EGC. By Holter, six patients (30%) presented atrial and / or ventricular ectopy with higher frequency than mild. Junctional rhythm and 2: 1 atrioventricular occurred in one patient (5%). Analyzing the criteria for sinus node dysfunction, bradycardia was observed by Holter in 30% of the patients. There were no pauses longer than two seconds. By Ergometric test, 82% of children had chronotropic deficit. Follow-up more than 60 months and abnormal ECG were related to the presence of arrhythmias. Conclusion: The long term follow-up of patients undergoing anomalous pulmonary venous connection showed that regardless of the good clinical and echocardiographic results, the possibility of occurrence of atrial and / or ventricular arrhythmias highlight attention to the need for maintenance of regular clinical evaluations. / Introdução: A frequência de ocorrência da conexão anômala total de veias pulmonares (CATVP) varia nas diversas séries entre 5,9 a 7,1/100 mil nascidos vivos, representando 1 a 5 % dos casos de cardiopatia congênita. A evolução nos cuidados atuais leva à necessidade de abordagem de eventuais complicações tardias, como as arritmias. Objetivo: Avaliar a distribuição das arritmias e possíveis variáveis relacionadas em pacientes em pós operatório tardio de CATVP. Método: Análise dos dados de 20 pacientes operados de CATVP isolada, com revisão de prontuário e avaliação clínica e não invasiva de arritmias. Estudo estatístico para detecção de variáveis relacionadas. Resultados: As avaliações clínica e ecocardiográfica não evidenciaram alterações significativas. O eletrocardiograma (ECG) de 12 derivações apresentou anormalidades para a idade em 13 dos 20 pacientes estudados (65%). Ao Holter, 6 pacientes (30%) apresentaram ectopias atriais e/ou ventriculares de frequência maior que discreta. Ritmo juncional e bloqueio atrioventricular 2:1 aconteceram em um paciente (5%). Analisando-se os critérios para disfunção do nó sinusal, observou-se bradicardia ao holter em 30% dos pacientes. Não houve pausas maiores que 2 segundos. Ao teste ergométrico, 82% das crianças apresentaram déficit cronotrópico. Seguimento maior que 60 meses e ECG anormal relacionaram-se à presença de arritmias. Conclusão: O seguimento em longo prazo de pacientes operados de conexão anômala total de veias pulmonares mostrou que independentemente dos bons resultados clínicos e ecocardiográficos, existe a possibilidade de ocorrência de arritmias atriais e/ou ventriculares, chamando a atenção para a necessidade de manutenção de avaliações clinicas regulares.
166

IdentificaÃÃo de linfonodos sentinela da mama com azul de metileno em modelo canino / Identification of sentinel lymph nodes in breast methylene blue in a canine model

Ranieri dos Santos Rolim 17 December 2010 (has links)
CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / Objetivos. Desenvolver um modelo experimental para identificaÃÃo de linfonodo sentinela (LS) da mama da cadela com uso de corante azul de metileno e comparÃ-lo com o azul patente, controlados por tecnÃcio. MÃtodos. O trabalho foi realizado em 23 cadelas, tendo-se observado a marcaÃÃo dos LS do primeiro par superior de mamas ao se injetarem 0,2 ml de TecnÃcio 99m ligado ao fitato (Tc 99m) e 0,5 ml de azul patente Guerbet V 2,5 % nos espaÃos subpapilares das mamas direitas e 0,2 ml de Tc-99m e 0,5 ml do azul de metileno 1 % nos mesmos espaÃos das mamas esquerdas. Resultados. Na mama direita, as tÃcnicas de biopsia de LS quando utilizados o Tc-99m e azul patente foram concordantes. Dos 23 LS estudados, somente um nÃo corou nem foi captante. O azul patente foi eficaz em 100 % quando comparado com os dois mÃtodos associados. Na mama esquerda, dos 23 LS estudados, somente dois nÃo coraram e um nÃo foi captante, sendo esta diferenÃa estatisticamente nÃo significante. A tÃcnica de biopsia do LS utilizando-se o azul de metileno apresentou-se com eficÃcia de 91,3 % quando utilizado isoladamente e de 100 % quando associado ao Tc-99m. ConclusÃo. O uso do azul de metileno associado ao radiofÃrmaco pode ser considerado como tÃcnica potencial na pesquisa transoperatÃria do LS das mamas, sendo uma opÃÃo menos onerosa e com menores efeitos alergÃnicos do que o azul patente / Objetivos. Desenvolver um modelo experimental para identificaÃÃo de linfonodo sentinela (LS) da mama da cadela com uso de corante azul de metileno e comparÃ-lo com o azul patente, controlados por tecnÃcio. MÃtodos. O trabalho foi realizado em 23 cadelas, tendo-se observado a marcaÃÃo dos LS do primeiro par superior de mamas ao se injetarem 0,2 ml de TecnÃcio 99m ligado ao fitato (Tc 99m) e 0,5 ml de azul patente Guerbet V 2,5 % nos espaÃos subpapilares das mamas direitas e 0,2 ml de Tc-99m e 0,5 ml do azul de metileno 1 % nos mesmos espaÃos das mamas esquerdas. Resultados. Na mama direita, as tÃcnicas de biopsia de LS quando utilizados o Tc-99m e azul patente foram concordantes. Dos 23 LS estudados, somente um nÃo corou nem foi captante. O azul patente foi eficaz em 100 % quando comparado com os dois mÃtodos associados. Na mama esquerda, dos 23 LS estudados, somente dois nÃo coraram e um nÃo foi captante, sendo esta diferenÃa estatisticamente nÃo significante. A tÃcnica de biopsia do LS utilizando-se o azul de metileno apresentou-se com eficÃcia de 91,3 % quando utilizado isoladamente e de 100 % quando associado ao Tc-99m. ConclusÃo. O uso do azul de metileno associado ao radiofÃrmaco pode ser considerado como tÃcnica potencial na pesquisa transoperatÃria do LS das mamas, sendo uma opÃÃo menos onerosa e com menores efeitos alergÃnicos do que o azul patente / Objectives. To develop an experimental model for identification of sentinel lymph node (SLN) of breast bitch with the use of methylene blue and compares it with the patent blue, both associated with technetium. Methods. 23 dogs, there was the marking of the SLN of the first upper pair of breasts to inject 0.2 ml of Tc-99m phytate bound to (99m) and 0.5 ml of patent blue Guerbet V 2,5 % in subpapilar spaces right breast and 0.2 ml of 99mTc and 0.5 ml of 1% methylene blue in the same spaces left breast. Results. In the right breast biopsy techniques using 99mTc SLN and blue dye are in agreement. Of the 23 SLN studied, only one was not flushed nor uptake. The patent blue was effective in 100% when compared with the two methods together. The left breast of 23 SLN studied, only two non-stained and one was not uptake, this difference was not statistically significant. The SLN biopsy technique using methylene blue appeared with a 91.3% effectiveness when used alone and 100% when associated with 99mTc. Conclusion: The use of methylene blue associated with the radiotracer technique can be considered as potential research intraoperative SLN of breast, suggesting a less costly and less allergenic effects that blue patent. / Objectives. To develop an experimental model for identification of sentinel lymph node (SLN) of breast bitch with the use of methylene blue and compares it with the patent blue, both associated with technetium. Methods. 23 dogs, there was the marking of the SLN of the first upper pair of breasts to inject 0.2 ml of Tc-99m phytate bound to (99m) and 0.5 ml of patent blue Guerbet V 2,5 % in subpapilar spaces right breast and 0.2 ml of 99mTc and 0.5 ml of 1% methylene blue in the same spaces left breast. Results. In the right breast biopsy techniques using 99mTc SLN and blue dye are in agreement. Of the 23 SLN studied, only one was not flushed nor uptake. The patent blue was effective in 100% when compared with the two methods together. The left breast of 23 SLN studied, only two non-stained and one was not uptake, this difference was not statistically significant. The SLN biopsy technique using methylene blue appeared with a 91.3% effectiveness when used alone and 100% when associated with 99mTc. Conclusion: The use of methylene blue associated with the radiotracer technique can be considered as potential research intraoperative SLN of breast, suggesting a less costly and less allergenic effects that blue patent.
167

Processos patológicos em linfonodos na espécie canina: revisão de literatura / Pathologic processes in canine lymph nodes: literature review

Laerte Aleixo Baldani 07 March 2006 (has links)
Os linfonodos podem ser compreendidos como estruturas integrantes de dois sistemas orgânicos, o circulatório e o imunológico, apresentando estrutura mutável decorrente do tipo, da intensidade e do tempo da estimulação antigênica. As doenças nodais são complexas devido ao grande número de agentes que atingem os linfonodos via linfa e por causa da complexidade inerente do sistema imunológico e suas doenças próprias. A linfadenopatia é um achado clínico muito comum em cães, e o seu significado não deve ser desprezado. Inúmeros processos patológicos são observados no linfonodo canino, particularmente as hiperplasias reacionais benignas, linfadenites e os linfomas, e a sua total compreenção requer o conhecimento de histofisiologia, noções de imunologia, e biologia molecular. O conhecimento dos métodos diagnósticos disponíveis tem fundamental importância para o manejo do paciente, permitindo um tratamento acurado e eficiente / The lymph nodes may be known as integrants of two organic systems, circulatory and immunological, demonstrating mutable structure depending on the type, intensity, and time of antigenic stimulation. Nodal diseases are complex, because of the large number of diseases reaching nodes via lymph and because of the inherent complexity of the immune system and its own diseases. Lymphadenopathy is a common clinical finding, Many pathological processes has been found in canine lymph nodes, primarily benign reative hiperplasia, lymphadenitis and lymphomas, and your complete comprehension requires knowledge in histophysiology, immunology notions, and molecular biology. An understanding of the available diagnostic methods has fundamental importance for patient management, allowing an accurate and efficient treatment
168

Avaliação citológica e histopatológica de linfonodos regionais em cães portadores de mastocitomas de graus 1, 2 ou 3 e sua importância na determinação da sobrevida / Cytological and histopathological evaluation of regional lymph nodes in dogs with grade 1, 2 or 3 mast cell tumors and their importance in determining survival.

Juliana Vieira Cirillo 13 March 2015 (has links)
Mastocitomas são neoplasias muito prevalentes em cães, e podem ser classificados em graus 1, 2 ou 3 de acordo com características morfológicas. O objetivo deste projeto foi investigar a presença de metástases de mastocitomas caninos de graus 1, 2 ou 3 em linfonodos regionais, procurando correlaciona-las ao intervalo livre de doença e à sobrevida dos animais. Para isto, avaliamos os parâmetros clínicos dos animais e das neoplasias em 57 cães portadores de mastocitoma cutâneo, registrando-se a porcentagem dos casos que apresentaram metástases, o grau histológico da neoplasia e a sobrevida dos animais. Realizou-se análise citológica dos linfonodos regionais previamente ao procedimento cirúrgico e posteriormente estes linfonodos foram excisados junto com a neoplasia primária, independentemente do resultado da citologia. Os tumores foram graduados por histopatologia e submetidos à análise imunoistoquímica com c-kit e Ki-67. Os linfonodos foram avaliados por histopatologia, por análise histoquímica e por imunoistoquímica com c-kit. Foi realizada comparação entre o diagnóstico citológico e histopatológico dos linfonodos quanto à presença de metástases e entre fatores prognósticos associados à neoplasia e a presença de metástase em linfonodo. A citologia demonstrou ser um bom exame na detecção de metástase em linfonodo de cães portadores de mastocitoma cutâneo, e foram observadas células metastáticas em 36 casos (36/46). Na análise histológica dos linfonodos, observamos um maior índice de metástase nos animais diagnosticados com mastocitomas de grau 3, segundo a graduação de Patnaik, e com mastocitomas de alto grau, segundo a graduação de Kiupel. No entanto, não encontramos uma associação significativa entre a presença de metástase em linfonodo e o grau histológico da neoplasia. O grau histológico associou-se à sobrevida independentemente da presença de metástase em linfonodo. Não houve associação entre o padrão de expressão da proteína KIT na neoplasia com a presença de metástase em linfonodo, nem a sobrevida. A utilização da imunoistoquímica em linfonodos metastáticos com c-kit foi um método eficaz, com predomínio do mesmo padrão de marcação da proteína KIT na neoplasia primária e no linfonodo. A expressão de Ki-67 na neoplasia correlacionou-se à presença de metástase em linfonodo e à uma menor sobrevida e intervalo livre de doença nos animais que apresentavam mastocitomas com índice de Ki-67 acima de 23. Na análise da sobrevida, não observamos diferença na sobrevida, nem no intervalo livre de doença, comparando-se os animais que apresentavam metástase em linfonodo e aqueles que não apresentavam, entretanto o índice de óbito e de progressão da doença neste estudo foram baixos. O intervalo livre de doença e sobrevida média não foram alcançados ao final do estudo. Os resultados sugerem que a presença de metástase em linfonodo não deve ser considerada como um fator prognóstico independente em cães diagnosticados com mastocitoma cutâneo, uma vez que outros fatores prognósticos, bem como a utilização de tratamentos adjuvantes, podem interferir de forma significativa na evolução destes pacientes. / Mast cell tumors are very prevalent in dogs, and can be classified in grades 1, 2 or 3 according to morphological characteristics.The aim of this study was to investigate the presence of metastases in regional lymph nodes of grade 1, 2 or 3 canine mast cell tumors, and correlate its presence to the disease-free interval and survival of the animals. For this, we evaluated the clinical parameters of animals and tumors in 57 dogs with cutaneous mast cell tumor, registering the percentage of cases with metastasis, histological grade of the tumor and survival of the animals. Cytological analysis of regional lymph nodes were performed prior to surgery and then these lymph nodes were excised along with the primary tumor, regardless of the result of cytology. The tumors were graded by histopathology and submitted to immunohistochemical analysis with c-kit and Ki-67. The lymph nodes were evaluated by histopathology, histochemistry and immunohistochemistry with c-kit. We compared the cytological and histopathological diagnosis of lymph nodes for the presence of metastases and compared prognostic factors associated with the primary tumor and the presence of metastasis in lymph node. Cytology proved to be a good method in detecting lymph node metastasis in dogs with cutaneous mast cell tumors and metastatic cells were observed in 36 cases (36/46). In the histological analysis of the lymph nodes, we observed a higher rate of metastasis in animals diagnosed with grade 3 mast cell tumors, according to the Patnaik grading system, and with high-grade mast cell tumors, according to the Kiupel grading system. However, we have not found a significant association between the presence of metastasis in lymph nodes and the histological grade of the tumors. Histological grade associated with survival independent of the presence of lymph node metastasis. In addition, there was no association between the pattern of KIT protein expression in the primary tumor and lymph node metastasies or survival. The use of immunohistochemistry in metastatic lymph nodes with c-kit is an effective method, with prevalence of the same KIT pattern in primary tumor and lymph node. The expression of Ki-67 in the primary tumor correlated with lymph node metastasis, survival and disease-free-time, and it was observed in animals in which mast cell tumors had a Ki-67 index higher than 23. In survival analysis, we observed no difference in survival or in disease-free interval, comparing the animals with lymph node metastasis and those who did not had, though the death rate and disease progression in this study were low. The disease-free interval and median survival were not reached at the end of the study. The results suggest that the presence of lymph node metastasis should not be considered as an independent prognostic factor in dogs diagnosed with cutaneous mast cell tumors, since other prognostic factors, as well as the establishment of adjuvant treatment, can interfere significantly with the progression of these patients.
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Blood Plasma-Based Glycan Nodes as Lung Cancer Markers and the Problem of Biospecimen Integrity in a Multi-Site Clinical Study

January 2019 (has links)
abstract: Cancer is a major public health challenge and the second leading cause of death in the United States. Large amount of effort has been made to achieve sensitive and specific detection of cancer, and to predict the course of cancer. Glycans are promising avenues toward the diagnosis and prognosis of cancer, because aberrant glycosylation is a prevalent hallmark of diverse types of cancer. A bottom-up “glycan node analysis” approach was employed as a useful tool, which captures most essential glycan features from blood plasma or serum (P/S) specimens and quantifies them as single analytical signals, to a lung cancer set from the Women Epidemiology Lung Cancer (WELCA) study. In addition, developments were performed to simplify a relatively cumbersome step involved in sample preparation of glycan node analysis. Furthermore, as a biomarker discovery research, one crucial concern of the glycan node analysis is to ensure that the specimen integrity has not been compromised for the employed P/S samples. A simple P/S integrity quality assurance assay was applied to the same sample set from WELCA study, which also afford the opportunity to evaluate the effects of different collection sites on sample integrity in a multisite clinical trial. Here, 208 samples from lung cancer patients and 207 age-matched controls enrolled in the WELCA study were analyzed by glycan node analysis. Glycan features, quantified as single analytical signals, including 2-linked mannose, α2‐6 sialylation, β1‐4 branching, β1‐6 branching, 4-linked GlcNAc, and outer-arm fucosylation, exhibited abilities to distinguish lung cancer cases from controls and predict survival in patients. To circumvent the laborious preparation steps for permethylation of glycan node analysis, a spin column-free (SCF) glycan permethylation procedure was developed, applicable to both intact glycan analysis or glycan node analysis, with improved or comparable permethylation efficiency relative to some widely-used spin column-based procedures. Biospecimen integrity of the same set of plasma samples from WELCA study was evaluated by a simple intact protein assay (ΔS-Cysteinylated-Albumin), which quantifies cumulative exposure of P/S to thawed conditions (-30 °C). Notable differences were observed between different groups of samples with various initial handling/storage conditions, as well as among the different collection sites. / Dissertation/Thesis / Doctoral Dissertation Biochemistry 2019
170

Scalable Energy-efficient Location-Aided Routing (SELAR) Protocol for Wireless Sensor Networks

Lukachan, George 01 November 2005 (has links)
Large-scale wireless sensor networks consist of thousands of tiny and low cost nodes with very limited energy, computing power and communication capabilities. They have a myriad of possible applications. They can be used in hazardous and hostile environments to sense for deadly gases and high temperatures, in personal area networks to monitor vital signs, in military and civilian environments for intrusion detection and tracking, emergency operations, etc. In large scale wireless sensor networks the protocols need to be scalable and energy-efficient. Further, new strategies are needed to address the well-known energy depletion problem that nodes close to the sink node face. In this thesis the Scalable Energy-efficient Location-Aided Routing (SELAR) protocol for wireless sensor networks is proposed to solve the above mentioned problems. In SELAR, nodes use location and energy information of the neighboring nodes to perform the routing function. Further, the sink node is moved during the network operation to increase the network lifetime. By means of simulations, the SELAR protocol is evaluated and compared with two very well-known protocols - LEACH (Low-Energy Adaptive-Clustering Hierarchy) and MTE (Minimum Transmission Energy). The results indicate that in realistic senarios,SELAR delivers up to 12 times more and up to 1.4 times more data packets to the base station than LEACH and MTE respectively. It was also seen from the results that for realistic scenarios, SELAR with moving base station has up to 5 times and up to 27 times more lifetime duration compared to MTE and LEACH respectively.

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