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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.
11

Investigation of the role of VML in the establishment of Drosophila embryonic dorsal-ventral polarity

Zhang, Yuan, M.A. in Cellular and Molecular Biology 05 November 2012 (has links)
Drosophila embryonic dorsal-ventral (D-V) polarity is defined by the expression of the gene pipe in the ventral cells of the follicular epithelium surrounding the developing oocyte. pipe encodes a sulfotransferase that transfers sulfate groups to several protein components of the vitelline membrane layer of the eggshell, including Vitelline Membrane-Like protein (VML). These sulfated proteins represent a ventral cue embedded in the eggshell, which, during embryogenesis, leads to the spatially-restricted activation of a serine protease cascade involving Gastrulation Defective (GD), Snake and Easter. Several important pieces of information missing from our understanding of Drosophila D-V patterning include the structures of the carbohydrates borne by the Pipe targets that represent the direct substrates for Pipe and how the Pipe-sulfated ventral cue triggers the spatially-regulated activation of the serine protease cascade. Two major goals of my studies on VML are to elucidate the structures of Pipe-sulfated carbohydrates associated with VML and to identify proteins that interact with VML in a Pipe-dependent manner. To achieve the first goal, I explored different purification systems to isolate VML and eventually found a way of partially purifying VML from Drosophila ovaries. Mass spectrometric analysis of the purified VML is underway to determine the carbohydrate structures on VML and the sites of Pipe-mediated sulfation. Future experiments will involve identification of putative enzymes responsible for the glycosylation of VML and examination of their requirements in D-V patterning. To identify interacting partners of VML, a strategy combining in vivo biotinylation of VML, reversible protein crosslinking and Streptavidin purification of crosslinked complexes will be used. In the second section of my studies, I have demonstrated that VML bearing a biotin acceptor peptide (BAP) tag can be efficiently biotinylated in vivo by co-expressing it with a biotin protein ligase BirA in the follicle cells. As an extension of the application of the approach, I also show that the Torso-like protein, which is localized to the poles of the vitelline membrane and whose polar localization is crucial for Drosophila terminal patterning, can also be biotinylated in vivo when the BAP-tagged protein is co-expressed with BirA in the follicle cells. / text
12

Ventral medullary organization for cardiorespiratory control

Jung, Ranu January 1991 (has links)
No description available.
13

Functional Neuroanatomic Analysis of the Response of the Nucleus Accumbens to Acute and Chronic Drugs of Abuse

Walsh, Ryan Robert January 2003 (has links)
No description available.
14

Structure and functions of the ventral tube of the clover springtail Sminthurus viridis (Collembola Sminthuridae)

Chen, C-G., Chen, T., Hua, B-Z., Wan, Tao Ruan 29 January 2019 (has links)
Yes / Springtails (Collembola) are unique in Hexapoda for bearing a ventral tube (collophore) on the first abdominal segment. Although numerous studies have been conducted on the functions of the ventral tube, its fine structure has not been thoroughly elucidated to date. In this paper, we observed the jumping behavior of the clover springtail Sminthurus viridis (Linnaeus, 1758) and dissected the ventral tube using light microscopy to elucidate the fine structure and the possible function of the ventral tube. The results show that a pair of eversible vesicles can be extended from the apical opening of the ventral tube. The eversible vesicles are furnished with numerous small papillae, and can be divided into a basal part and a distal part. The eversible vesicles have a central lumen connected to the tiny papillae and leading to the body cavity. The eversible vesicles can reach any part of the body, and may serve as following functions: (a) absorbing moisture; (b) uptaking water; (c) cleaning the body surface; and (d) fastening the body on a smooth surface.
15

Espondilectomia parcial ventral cervical com osteotomia piezoelétrica e convencional em coelhos (Oryctolagus cuniculus) / Cervical ventral partial spondilectomy with piezoeletric and conventional osteotomy in rabbits (Oryctolagus cuniculus)

Roscamp, Marcelo 09 October 2017 (has links)
Submitted by Marcelo Roscamp (marcelo@ortopediapet.com) on 2017-11-16T13:57:30Z No. of bitstreams: 1 Dissertação_Marcelo_Roscamp.pdf: 9443012 bytes, checksum: 69bacbdda807a3e9fee0f785465385c3 (MD5) / Submitted by Marcelo Roscamp (marcelo@ortopediapet.com) on 2017-11-22T14:06:58Z No. of bitstreams: 1 Dissertação_Marcelo_Roscamp.pdf: 9443012 bytes, checksum: 69bacbdda807a3e9fee0f785465385c3 (MD5) / Submitted by Marcelo Roscamp (marcelo@ortopediapet.com) on 2017-11-22T18:09:13Z No. of bitstreams: 1 Dissertação_Marcelo_Roscamp.pdf: 9443012 bytes, checksum: 69bacbdda807a3e9fee0f785465385c3 (MD5) / Submitted by Marcelo Roscamp (marcelo@ortopediapet.com) on 2017-11-22T18:12:23Z No. of bitstreams: 1 Dissertação_Marcelo_Roscamp.pdf: 9443012 bytes, checksum: 69bacbdda807a3e9fee0f785465385c3 (MD5) / Submitted by Marcelo Roscamp (marcelo@ortopediapet.com) on 2017-11-22T19:44:21Z No. of bitstreams: 1 Dissertação_Marcelo_Roscamp.pdf: 9443012 bytes, checksum: 69bacbdda807a3e9fee0f785465385c3 (MD5) / Submitted by Marcelo Roscamp (marcelo@ortopediapet.com) on 2017-11-23T11:57:14Z No. of bitstreams: 1 Dissertação_Marcelo_Roscamp.pdf: 9443012 bytes, checksum: 69bacbdda807a3e9fee0f785465385c3 (MD5) / Submitted by Marcelo Roscamp (marcelo@ortopediapet.com) on 2017-11-23T12:57:56Z No. of bitstreams: 1 Dissertação_Marcelo_Roscamp.pdf: 9443012 bytes, checksum: 69bacbdda807a3e9fee0f785465385c3 (MD5) / Submitted by Marcelo Roscamp (marcelo@ortopediapet.com) on 2017-11-23T13:16:32Z No. of bitstreams: 1 Dissertação_Marcelo_Roscamp.pdf: 9443012 bytes, checksum: 69bacbdda807a3e9fee0f785465385c3 (MD5) / Submitted by Marcelo Roscamp (marcelo@ortopediapet.com) on 2017-11-23T13:34:44Z No. of bitstreams: 1 Dissertação_Marcelo_Roscamp.pdf: 9443012 bytes, checksum: 69bacbdda807a3e9fee0f785465385c3 (MD5) / Submitted by Marcelo Roscamp (marcelo@ortopediapet.com) on 2017-11-23T17:24:55Z No. of bitstreams: 1 Dissertação_Marcelo_Roscamp.pdf: 9443012 bytes, checksum: 69bacbdda807a3e9fee0f785465385c3 (MD5) / Submitted by Marcelo Roscamp (marcelo@ortopediapet.com) on 2017-11-23T17:29:02Z No. of bitstreams: 1 Dissertação_Marcelo_Roscamp.pdf: 9443012 bytes, checksum: 69bacbdda807a3e9fee0f785465385c3 (MD5) / Submitted by Marcelo Roscamp (marcelo@ortopediapet.com) on 2017-11-24T12:05:24Z No. of bitstreams: 1 Dissertação_Marcelo_Roscamp.pdf: 9443012 bytes, checksum: 69bacbdda807a3e9fee0f785465385c3 (MD5) / Submitted by Marcelo Roscamp (marcelo@ortopediapet.com) on 2017-11-24T12:39:44Z No. of bitstreams: 1 Dissertação_Marcelo_Roscamp.pdf: 9443012 bytes, checksum: 69bacbdda807a3e9fee0f785465385c3 (MD5) / Submitted by Marcelo Roscamp (marcelo@ortopediapet.com) on 2017-11-24T16:47:38Z No. of bitstreams: 1 Dissertação_Marcelo_Roscamp.pdf: 9443012 bytes, checksum: 69bacbdda807a3e9fee0f785465385c3 (MD5) / Submitted by Marcelo Roscamp (marcelo@ortopediapet.com) on 2017-11-24T17:31:22Z No. of bitstreams: 1 Dissertação_Marcelo_Roscamp.pdf: 9443012 bytes, checksum: 69bacbdda807a3e9fee0f785465385c3 (MD5) / Submitted by Marcelo Roscamp (marcelo@ortopediapet.com) on 2017-11-27T11:40:50Z No. of bitstreams: 1 Dissertação_Marcelo_Roscamp.pdf: 9443012 bytes, checksum: 69bacbdda807a3e9fee0f785465385c3 (MD5) / Submitted by Marcelo Roscamp (marcelo@ortopediapet.com) on 2017-11-27T12:31:51Z No. of bitstreams: 1 Dissertação_Marcelo_Roscamp.pdf: 9443012 bytes, checksum: 69bacbdda807a3e9fee0f785465385c3 (MD5) / Submitted by Marcelo Roscamp (marcelo@ortopediapet.com) on 2017-11-27T13:03:15Z No. of bitstreams: 1 Dissertação_Marcelo_Roscamp.pdf: 9443012 bytes, checksum: 69bacbdda807a3e9fee0f785465385c3 (MD5) / Submitted by Marcelo Roscamp (marcelo@ortopediapet.com) on 2017-11-27T18:08:07Z No. of bitstreams: 1 Dissertação_Marcelo_Roscamp.pdf: 9443012 bytes, checksum: 69bacbdda807a3e9fee0f785465385c3 (MD5) / Submitted by Marcelo Roscamp (marcelo@ortopediapet.com) on 2017-11-28T12:13:08Z No. of bitstreams: 1 Dissertação_Marcelo_Roscamp.pdf: 9443012 bytes, checksum: 69bacbdda807a3e9fee0f785465385c3 (MD5) / Submitted by Marcelo Roscamp (marcelo@ortopediapet.com) on 2017-11-28T14:22:46Z No. of bitstreams: 1 Dissertação_Marcelo_Roscamp.pdf: 9443012 bytes, checksum: 69bacbdda807a3e9fee0f785465385c3 (MD5) / Submitted by Marcelo Roscamp (marcelo@ortopediapet.com) on 2017-11-28T14:31:56Z No. of bitstreams: 1 Dissertação_Marcelo_Roscamp.pdf: 9443012 bytes, checksum: 69bacbdda807a3e9fee0f785465385c3 (MD5) / Submitted by Marcelo Roscamp (marcelo@ortopediapet.com) on 2017-11-28T14:37:45Z No. of bitstreams: 1 Dissertação_Marcelo_Roscamp.pdf: 9443012 bytes, checksum: 69bacbdda807a3e9fee0f785465385c3 (MD5) / Submitted by Marcelo Roscamp (marcelo@ortopediapet.com) on 2017-11-28T19:04:28Z No. of bitstreams: 1 Dissertação_Marcelo_Roscamp.pdf: 9443012 bytes, checksum: 69bacbdda807a3e9fee0f785465385c3 (MD5) / Submitted by Marcelo Roscamp (marcelo@ortopediapet.com) on 2017-11-30T18:58:21Z No. of bitstreams: 1 Dissertação_Marcelo_Roscamp.pdf: 9443012 bytes, checksum: 69bacbdda807a3e9fee0f785465385c3 (MD5) / Submitted by Marcelo Roscamp (marcelo@ortopediapet.com) on 2017-12-04T14:43:23Z No. of bitstreams: 1 Dissertação_Marcelo_Roscamp.pdf: 9443012 bytes, checksum: 69bacbdda807a3e9fee0f785465385c3 (MD5) / Submitted by Marcelo Roscamp (marcelo@ortopediapet.com) on 2017-12-05T14:11:15Z No. of bitstreams: 1 Dissertação_Marcelo_Roscamp.pdf: 9443012 bytes, checksum: 69bacbdda807a3e9fee0f785465385c3 (MD5) / Submitted by Marcelo Roscamp (marcelo@ortopediapet.com) on 2017-12-11T18:47:11Z No. of bitstreams: 1 Dissertação_Marcelo_Roscamp.pdf: 9443012 bytes, checksum: 69bacbdda807a3e9fee0f785465385c3 (MD5) / Approved for entry into archive by Alexandra Maria Donadon Lusser Segali null (alexmar@fcav.unesp.br) on 2017-12-13T12:16:42Z (GMT) No. of bitstreams: 1 roscamp_m_me_jabo.pdf: 9443012 bytes, checksum: 69bacbdda807a3e9fee0f785465385c3 (MD5) / Made available in DSpace on 2017-12-13T12:16:42Z (GMT). No. of bitstreams: 1 roscamp_m_me_jabo.pdf: 9443012 bytes, checksum: 69bacbdda807a3e9fee0f785465385c3 (MD5) Previous issue date: 2017-10-09 / A cirurgia piezoelétrica ou piezocirurgia é utilizada há várias décadas, porém em medicina veterinária são escassos os artigos publicados utilizando esta modalidade em cirurgias descompressivas da coluna vertebral de cães e gatos. Assim, aventou-se com esse trabalho investigar a aplicabilidade da mesma na realização da espondilectomia parcial ventral cervical (EPVC), comparando-a com a técnica convencional que utiliza brocas esféricas de alta rotação para o desgaste ósseo, utilizando o coelho (Oryctolagus cuniculus) como modelo experimental de cães e gatos. Para tanto foi utilizado o aparelho médico Mastersonic®, que possui duas peças de mão, uma piezoelétrica com ponteira ultrassônica tipo cinzel delicado (T1) e na outra, motor de alta rotação com brocas esférica de 2 mm (técnica convencional) (T2). A EPVC foi realizada entre a terceira e quarta vértebras cervicais e cada técnica foi realizada em 15 animais, devidamente anestesiados, os quais foram avaliados quanto à duração de cada etapa da cirurgia, variações de temperatura durante a execução da EPVC, visibilidade do campo cirúrgico, complicações trans e pós-operatórias e monitoração anestésica. Aos 14, 28 e 56 dias de pós-operatório (PO), cinco animais de cada tratamento foram submetidos à eutanásia e realizado estudo histopatológico do local da cirurgia, avaliando à resposta inflamatória, à cicatrização óssea e as lesões medulares. Os resultados mostraram que T1 demandou mais tempo para a execução da curetagem e maior perda de temperatura no foco cirúrgico durante a cirurgia. O tempo de acesso cirúrgico reduziu progressivamente em torno de 50% até o oitavo procedimento de cada tratamento (T1 e T2), e após isso se manteve com a mesma duração nos dois tratamentos. O tempo de uso do aparelho foi mais homogêneo em T1 e diminuiu progressivamente em T2, mas ao avaliar o tempo total da técnica de EPVC, não houve diferença entre os tratamentos. O T1 proporcionou melhor visibilidade do campo cirúrgico, com apenas um caso de sangramento ósseo, contra seis casos em T2. Observaram-se quatro casos de hemorragia de seio venoso vertebral durante a curetagem no T1 e dois casos no T2. Também ocorreram três casos de déficits proprioceptivos transitórios, com duração de até 72 horas no T1. A temperatura corporal e a taxa de uso do isoflurano decaíram com o tempo nos dois tratamentos, assim como a frequência cardíaca em T1. No estudo histopatológico observou-se resposta inflamatória mais ativa em T1 aos 14 dias de PO, porém aos 28 e 56 dias de PO foi semelhante entre os tratamentos, assim como a cicatrização óssea. Ainda houve mais lesões medulares com a piezocirurgia (T1), principalmente aos 14 e 28 dias de PO, com presença de malácia, esferócitos e células “Gitter”. Enquanto que na técnica convencional (T2), notou-se discreta degeneração Walleriana, apenas aos 14 dias de PO. Conclui-se que a piezocirurgia é aplicável na realização da EPVC com excelente visibilidade do campo operatório, facilidade de manuseio e rápida curva de aprendizagem, no entanto, demandou maior tempo para execução da espondilectomia e provocou mais complicações cirúrgicas e de lesões medulares, quando comparada à técnica convencional. / Piezoelectric surgery or piezosurgery has been used for several decades, but in veterinary medicine, articles published using this modality in decompressive surgery of the spine of dogs and cats are scarce. The aim of this study was to investigate the applicability of this technique to the performance of cervical ventral partial spondylectomy (CVPS), comparing it with the conventional technique using high-rotation spherical drills for bone wear using rabbit (Oryctolagus cuniculus) as an experimental model of dogs and cats.. For this was used Mastersonic® medical device that has two hand pieces, one piezoelectric type with ultrasonic delicate chisel tip (T1) and the other, high speed engine with spherical drills 2 mm (conventional technique) (T2). The CVPS was held between the third and fourth cervical vertebrae and each technique was performed on 15 animals, under anesthesia, which were evaluated for the duration of each stage of surgery, temperature variations during the execution of CVPS, the surgical field visibility, trans and postoperative complications and anesthetic monitoring. At 14, 28 and 56 postoperative days (PO), five animals per treatment were euthanized, and histological studies were carried to the surgical site by assessing the inflammatory response, and bone healing spinal injuries. The results showed that T1 required more time for curettage execution and highest loss of temperature at the surgical focus during surgery. Surgical access time progressively reduced by 50% until the eighth procedure of each treatment (T1 and T2), and after that it remained the same duration in both treatments. The time of use of the device was more homogeneous in T1 and progressively decreased in T2, but when evaluating the total time of the CVPS technique, there was no difference between treatments. The T1 provided better visibility of the surgical field, with only one case of bone bleeding, against six cases in T2. Four cases of vertebral venous sinus hemorrhage were seen during curettage in T1 and two cases in T2. There were also three cases of transient proprioceptive deficits, lasting up to 72 hours in T1. Body temperature and the rate of use of isoflurane declined over time in both treatments, as did heart rate in T1. Histopathological study there was more active inflammatory response in T1 at 14 days postoperatively, but after 28 and 56 days postoperatively was similar among treatments, as well as to bone healing. There were still more spinal cord injuries with the piezosurgery (T1), especially at 14 and 28 days of PO, with presence of malacia, spherocytes and Gitter cells. While the conventional technique (T2), it was noted discrete Wallerian degeneration, only at 14 days postoperatively. It is concluded that the piezosurgery is applicable in the performance of the CVPS with excellent visibility of the operative field, ease of handling and rapid learning curve, however, demanded more time for the execution of the spondylectomy and caused more surgical complications and spinal cord injuries, when compared to the conventional technique.
16

Modelo experimental para o estudo do comportamento optico da parede abdominal e sua interação com um material protetico por biospeckle : trabalho experimental em ratos / Optical behavior of the abdominal wall and its interaction with a synthetic material in the surgery of the incisional hernias: experimental study in rats

Nieri, Tamara Maria 29 August 2005 (has links)
Orientador: Marco Antonio de Oliveira Peres / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciencias Medicas / Made available in DSpace on 2018-08-07T03:24:04Z (GMT). No. of bitstreams: 1 Nieri_TamaraMaria_D.pdf: 4800971 bytes, checksum: 479a127e9ad76c6ea9d61025a1714615 (MD5) Previous issue date: 2005 / Resumo: Hérnia incisional, afecção que incide em 2 a 15% das laparotomias, é uma complicação cirúrgica que continuará acompanhando, como vem fazendo até hoje, as cirurgias abdominais. A utilização mais freqüente de próteses tem alcançado resultados mais significativos na cura desta afecção. Diversos estudos vêm sendo realizados com diferentes métodos de avaliação da biocompatibilidade dos materiais protéticos. Modelos experimentais permitem estudos detalhados destas interações, no campo da anatomia, da fisiologia, da bioquímica, da microbiologia e da mecânica. O presente trabalho apresentou a criação de um modelo animal, que se mostrou viável, para o estudo da atividade tecidual da parede abdominal em sua interação com um material protético, utilizando um dos fenômenos ópticos da luz coerente (Laser), o biospeckle. Foram analisados 50 ratos Wistar machos, divididos em quatro grupos: Grupo 1 com 10 animais não submetidos à cirurgia; Grupo 2 com 10 animais submetidos a cirurgia sem a colocação de tela; Grupo 3 com 20 animais submetidos a cirurgia com colocação de tela de polipropileno pré-peritonial; Grupo 4 (Sham) com 10 animais. Nenhum animal apresentou complicações pós-operatórias, sendo levados, no 20º PO, ao ensaio óptico, que consistiu no posicionamento do animal anestesiado, em decúbito dorsal horizontal, sobre uma mesa óptica, tendo um feixe de Laser iluminando um ponto da linha média da parede abdominal. Um sistema de aquisição de imagens (LSI), composto por uma câmera (Charge Coupled Device - CCD), um processador digital de imagens e um microcomputador, captaram e processaram as imagens gerando um padrão STS (Space Time Speckle); este padrão, processado por um software, gerou uma Matriz de Ocorrências Modificada (MOM). O mesmo software calculou, a partir da MOM, o Módulo de Dispersão, um valor absoluto sem unidade, que foi o parâmetro de comparação dos espécimes, após tratamento estatístico. A análise dos dados obtidos permitiu concluir que o modelo animal criado é viável e que não houve diferença significativa, nos quatro grupos estudados, da atividade tecidual da parede abdominal de ratos, com e sem a implantação cirúrgica de prótese de polipropileno, quando utilizado o biospeckle / Abstract: Incisional hernia is an affection that occurs on 2% to 15% of laparotomy procedures, being also considered a surgical complication which has been following abdominal surgical procedures. Prosthesis applications have been conquered satisfactory results in heeling such affection. The literature discloses many research work reports on biocompatibility evaluation of prosthetic materials. Experimental models allow detailed studies of theses interactions under the anatomy point of view, as well as under the physiology, biochemistry, microbiology and mechanics. This research work reports the generation of an animal model useful in supporting the abdominal tissue activity considering its interaction with a prosthetic material, by means of technique based on the biospeckle phenomena. This way, 50 Wistar male rats were divided into four groups: Group 1, composed of ten animals not submitted to surgery; group 2, composed of ten animals submitted to surgery without polypropylene mesh; group 3, composed of 20 animals submitted to surgery followed by the mesh placement; group 4, sham with ten animals. None of the animals presented post surgical complications being submitted to the optical tests at the 20th postoperative day. The analysis from the biospeckle tests indicated that no significative difference was observed on the abdominal wall tissue activity in the four groups considered, with and without polypropylene mesh prosthesis implantation / Doutorado / Cirurgia / Doutor em Cirurgia
17

Mastócitos no lobo ventral da próstata, no epidídimo e no testículo de ratos UChB (consumidores voluntários de etanol a 10%) / Mast cells in the ventral prostate, epididymis and testis of UchB - ethanol preferring rats (10% v/v high ethanol voluntary intake)

Mendes, Leonardo de Oliveira, 1985- 16 August 2018 (has links)
Orientadores: Francisco Eduardo Martinez, Sônia Maria Oliani / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-16T00:16:01Z (GMT). No. of bitstreams: 1 Mendes_LeonardodeOliveira_M.pdf: 2247960 bytes, checksum: ded01bbf76485b4e300f7195c6927ee3 (MD5) Previous issue date: 2010 / Resumo: O alcoolismo tem atingido proporções alarmantes em todo o mundo, porém são escassas as investigações sobre o efeito inflamatório do etanol nos órgãos reprodutivos. O mastócito é uma das principais células envolvidas nos processos inflamatórios, com a presença de dois subtipos em roedores, de tecido conjuntivo (CTMC) e de mucosa (MMC). O objetivo desse trabalho é localizar e quantificar os mastócitos no lobo ventral da próstata, testículo e epidídimo de ratos UChB e avaliar o possível efeito do etanol sobre o número de mastócitos nos órgãos analisados. Os animais foram divididos em três grupos experimentais (n=10/grupo): UChB com administração de etanol a 10% (UChBet), UChB sem administração de etanol (UChBco) e Wistar (W). Amostras do lobo ventral da próstata, do epidídimo e do testículo direitos foram coletadas após 180 dias de experimentação e processadas para análise em microscopia de luz. O material foi corado com azul de toluidina para identificação dos mastócitos totais, além de imunohistoquímica para identificação dos CTMC. Os animais que receberam etanol apresentaram maior quantidade de mastócitos desgranulados na próstata. Não houve diferença estatística no número de mastócitos, intactos e desgranulados, no testículo. O epidídimo apresentou diferenças de acordo com o segmento analisado. Houve maior densidade de mastócitos intactos e desgranulados no UChBet que no UChBco no segmento inicial. O grupo W apresentou elevada densidade de mastócitos intactos na região da cabeça, não havendo diferença estatística quanto aos mastócitos desgranulados nesta região. A região do corpo do epidídimo não revelou diferenças entre os grupos para os mastócitos intactos, porém quanto aos mastócitos desgranulados houve aumento do número nos animais que receberam etanol. Não houve diferenças quanto ao número de mastócitos intactos na região da cauda do epidídimo, porém houve aumento de mastócitos desgranulados no UChBet. A próstata dos animais UChBet apresentou maior quantidade de CTMC, além de número maior de MMC. Houve maior quantidade de CTMC no testículo de ratos W e, proporcionalmente, maior quantidade de MMC nos grupos UChB. No epidídimo houve menor marcação para CTMC nos animais UChB, com aumento proporcional de MMC. Conclui-se que o etanol aumenta o número de mastócitos desgranulados e de MMC e, consequentemente, pode desencadear processos inflamatórios na próstata, epidídimo e testículo de ratos UChB. / Abstract: Alcoholism has reached alarming proportions throughout the world, but there is little research on the inflammatory effect of ethanol in the reproductive organs. The mast cell, which is one of the main cells involved in inflammatory processes, is known to have two subtypes in rodents, connective (CTMC) and mucosal (MMC) tissue. Hence, the aim of this work is to locate and quantify mast cells in the ventral lobe of the prostate, in the testis and epididymis of UChB rats and then assess if there is a relation between ethanol ingestion and the number of mast cells in these organs. The animals were divided into three experimental groups (n = 10/group): UChB rats that received 10% ethanol administration (UChBet); UChB rats without ethanol administration (UChBco); and Wistar rats (W). Samples of the ventral lobe of the prostate, right testis and right epididymis were collected after 180 days of experiments and processed for light microscopy analysis. The material was stained with toluidine blue for identification of total mast cells and immunohistochemistry was performed for CTMC identification. The animals who received ethanol exhibited high density of degranulated mast cells in the ventral prostate. There wasn't statistic difference in the number of mast cells, intact e degranulated, in the testis. The epididymis showed differences according to the analyzed segment. There was a higher density of intact and degranulated mast cells in UChBet when compared to UChBco in the initial segment. A high density of intact mast cells in the epididymal caput was observed in W, with no difference in the degranulated cells regarding this region. There was no difference between groups for intact mast cells in the region of the epididymal corpus, but the number of degranulated mast cells was higher in animals that received ethanol. There was no difference regarding the number of intact mast cells in the epididymal cauda, but the number of degranulated mast cells was higher in animals that received ethanol. There was a greater number of CTMC in the prostate of UChBet rats and a greater amount of MMC as well. There was higher amount of CTMC in the W rat testis and, proportionally, greater amount MMC in UChB groups. Staining for CTMC in epididymis of UChB animals was lower than W animals, which allows the establishment of a higher proportion of MMC in these animals. We concluded that ethanol increases the number of degranulated mast cells and MMC, and thus, it could be promoting inflammation in the prostate, epididymis and testis of UChB rats. / Mestrado / Histologia / Mestre em Biologia Celular e Estrutural
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Individual Differences in Neural Reward and Threat Processing: Identifying Pathways of Risk and Resilience for Psychopathology

Nikolova, Yuliya January 2014 (has links)
<p>The goal of this dissertation is two-fold: 1) to identify novel biological pathways implicating individual differences in reward and threat processing in the emergence of risk and resilience for psychopathology, 2) to identify novel genetic and epigenetic predictors of the inter-individual variability in these biological pathways. Four specific studies are reported wherein blood oxygen-level dependent functional magnetic resonance imaging (BOLD fMRI) was used to measure individual differences in threat-related amygdala reactivity and reward-related ventral striatum (VS) reactivity; self-report was used to measure of mood and psychopathology as well as the experience of stressful life events. In addition, DNA was derived from peripheral tissues to identify specific genetic and epigenetic markers.</p><p>Results from Study 1 demonstrate that individuals with relatively low reward-related VS reactivity show stress-related reductions in positive affect, while those with high VS reactivity remain resilient to these potentially depressogenic effects. Heightened VS reactivity was, however, associated with stress-related increases in problem drinking in Study 2. Importantly, this effect only occurred in individuals showing concomitantly reduced threat-related amygdala reactivity. Study 3 demonstrates that using a multilocus genetic profile capturing the cumulative impact of five functional polymorphic loci on dopamine signaling increases power to explain variability in reward-related VS reactivity relative to an approach considering each locus independently. Finally, Study 4 provides evidence that methylation in the proximal promoter of the serotonin transporter gene is negatively correlated with gene expression and positively correlated with threat-related amygdala reactivity above and beyond the effects of commonly studied functional DNA-sequence based variation in the same genomic vicinity.</p><p>The results from these studies implicate novel biological pathways, namely reward-related VS reactivity and threat-related amygdala reactivity, as predictors of relative risk or resilience for psychopathology particularly in response to stressful life events. Moreover, the results suggest that genetic and epigenetic markers may serve as easily accessible peripheral tissue proxies for these neural phenotypes and, ultimately, risk and resilience. Such markers may eventually be harnessed to identify vulnerable individuals and facilitate targeted early intervention or prevention efforts.</p> / Dissertation
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Dopamine responses in the ventral straitum contribute to ethanol preference and consumption and, mu opioid receptors do not mediate ethanol stimulated dopamine release

Ramachandra, Vorani Sashrika 27 October 2010 (has links)
The goal of this dissertation was two fold: 1) To relate dopamine responses in the ventral striatum to ethanol preference and consumption, and 2) to investigate the role of the mu opioid receptors in this ethanol induced dopamine release in the ventral striatum. First a two bottle choice experiment established that a substrain of C57BL/6 mice (C57BL/6NCrl) had significantly less preference for and consumption of ethanol than a second substrain of mouse based on the same background (C57BL6/J). The C57BL/6 strain has been extensively used in alcohol drinking studies and is well known for it’s propensity to consume alcohol over water. To determine if differences in ventral striatal dopamine response vii could contribute to this variability in drinking behavior, we characterized the dopamine response in both substrains of mice after intraperitoneal injections of 1.0, 2.0 or 3.0 g/kg ethanol or saline. We found that the acute intraperitoneal ethanol injections in naïve mice caused a significant elevation in dopamine in both substrains at all three doses with a significant difference between substrains at the two highest alcohol doses. Therefore, ethanol induced dopamine release in the ventral striatum may contribute to ethanol preference and consumption. Next, we investigated the effect of acute intraperitoneal ethanol injections on naïve mu opioid receptor knockout mice and in mice pretreated with a mu opioid receptor antagonist. The mice used were all established on the C57BL/6J background. We found that ventral striatal dopamine response was similar in these mice after 1.0, 2.0 and 3.0 g/kg intraperitoneal ethanol injections compared to appropriate controls. As both gene deletion and pharmacological blockade of the mu opioid receptor did not affect ethanol stimulated dopamine release, it points to the conclusion that this receptor may not play a significant role in ethanol induced ventral striatal dopamine release. / text
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Du stade juvénile au stade adulte : évolution des troubles de la transmission dopaminergique chez les rats ayant subi la lésion néonatale de l'hippocampe ventral et implications pour la physiopathologie de la schizophrénie

Bertrand, Jean-Baptiste 17 December 2007 (has links) (PDF)
Dans ce travail, nous avons développé le modèle de rat ayant subi une lésion néonatale de l'hippocampe ventral (rat LNHV), un outil reconnu pour l'étude de la schizophrénie. <br />Nous avons validé l'utilisation de l'imagerie anatomique (IRM) comme outil permettant une détection fiable et précoce (avant la puberté) de la taille et la cible des lésions, pour remplacer l'évaluation post mortem.<br />Au niveau comportemental, nous avons montré que le nombre des anomalies qui sont associées à des troubles de la transmission dopaminergique augmente du stade juvénile à l'âge adulte chez les animaux LNHV. <br />Au niveau neurochimique, nous avons montré que les animaux LNHV présentent des altérations des efflux de dopamine au niveau mésocorticolimbique (noyau accumbens et cortex préfrontal) qui n'apparaissent qu'après la puberté. <br />Nos résultats confirment l'implication majeure de la dopamine dans la physiopathologie de la schizophrénie et soulignent l'importance des facteurs qui pourraient précipiter l'émergence de la maladie au moment de l'adolescence.

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