Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1981. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING. / Bibliography: leaves 150-153. / by Martha Lane Gray. / M.S.

Resumo: Considerando a importância da eubiota intestinal na saúde dos animais, o papel da dieta em sua composição e metabolismo tem sido estudado. Neste aspecto os prebióticos têm merecido destaque, incluindo-se a parede celular de leveduras (PCL), uma fonte natural de mananoligossacarídeos. Para o estudo de seu potencial prebiótico para cães, foram empregadas quatro dietas isonutrientes com inclusão de 0% (T0), 0,15% (T15), 0,30% (T30) e 0,45% (T45) de PCL. Foram utilizados oito Beagles adultos, divididos em dois quadrados latinos 4 X 4. Em cada período uma fase de adaptação de 15 dias precedeu 5 dias de coleta total de fezes para o ensaio de digestibilidade e 1 dia de coleta de fezes frescas para enumeração bacteriana, mensuração de pH e determinação das concentrações de ácidos graxos de cadeia curta e aminas bioativas. No dia 21 de cada período, amostra de sangue foi colhida para quantificação imunofenotípica por citometria de fluxo das subpopulações linfocitárias CD5+CD4+, CD5+, CD5+CD8+, CD45+ e CD45+CD21+. Os dados foram avaliados pelo Proc GLM do SAS, sendo as médias comparadas pelo teste de Tukey e por contraste polinomial e ortogonal (p<0,1). Os coeficientes de digestibilidade dos nutrientes não variaram com a inclusão de PCL (p>0,1). A inclusão de PCL não resultou em diferenças quanto às contagens de anaeróbios totais, aeróbios totais, bifidobactéria, lactobacilos, clostridios nas fezes dos cães (p>0.1). Verificou-se aumento linear na concentração fecal de butirato (p=0,055), redução linear das concentrações fecais de tiramina (P=0,1) e histamina (P=0,07) e redução quadrática de feniletilamina e triptamina (P=0,07). Os cães apresentaram, também, aumento linear na concentração de linfócitos CD5+ (P=0,10) e maior número de linfócitos CD45+CD21+ (P=0,053) mediante ingestão de PCL. Concluiu-se que a PCL apresenta efeito prebiótico... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Considering the importance of the intestinal microbiota to the animal health, the role of diet upon microbiota composition and metabolism have been studied. Prebiotics have been emphasized on this regard, including the yeasts cell walls (YCW), a natural source of mannanoligosaccharides. To study the prebiotic potential of this compound for dogs, four isonutrient diets were used with inclusion of 0% (T0), 0,15% (T15), 0,30% (T30) and 0,45% (T45) of YCW. Eight Beagles adults were used, arranged in two 4 X 4 Latin squares. In each replicate an adaptation phase of 15 days preceded a 5 days of total feces collection for digestibility trial and 1 day collection of fresh fecal samples for bacterial enumeration, pH measurement and determination of short chain fatty-acids and bioactive amines concentration. On day 21, a blood samples were collected for immunophenotypic quantification of lymphocyte subsets CD5+CD4+, CD5+, CD5+CD8+, CD45+ e CD45+CD21+ through flow cytometry. The data were evaluated using Proc GLM of SAS, means were compared by Tukey test and polinomial and orthogonal contrasts (p <0,1). The inclusion of YCW did not change the coefficient of total tract apparent digestibility of nutrients (p>0.1) nor the fecal bacterial enumeration (total aerobes and anaerobes, Bifidobacterium, Lactobacillus, Clostridium and Escherichia coli) in dog's feces (p>0.1). Fecal butirate concentration increased linearly with YCW addition (p=0,055), fecal concentrations of tyramine (P=0,1) and histamine (P=0,07) decreased linearly, and phenylethylamine (P=0,07) and tryptamine (P=0,07) concentrations showed a quadratic reduction with YCW consumption. Dogs also presented a linear increase in lymphocytes CD5+ concentration (P=0,10) and a greater CD45+CD21+ lymphocytes number (P=0,053) with YCW addition. In conclusion YCW presents a prebiotic (changing bacterial end product formation) and immunostimulating effect for dogs. / Orientador: Aulus Cavalieri Carciofi / Coorientador: Ruben Pablo Schocken-Iturrino / Banca: Áureo Evangelista Santana / Banca: Maria Beatriz Abreu Glória / Mestre

Orientador: Aureo Evangelista Santana / Coorientador: Letícia Abrahão Anai / Banca: Andrigo Barboza De Nardi / Banca: Sabryna Gouveia Calazans / Banca: Thiago Demarchi Munhoz / Banca: Felipe Augusto Ruiz Sueiro / Resumo: O linfoma pode ser caracterizado pela proliferação clonal de linfócitos malignos nos órgãos linfóides, podendo, porém, atingir diversos tecidos entre os quais a pele, denominado linfoma cutâneo. No cão, o linfoma cutâneo pode apresentar-se clinicamente por lesões localizadas ou generalizadas, podendo evoluir para lesões em placas e nódulos, muitas vezes edemaciados, ulcerados e hemorrágicos. Segundo avaliação histopatológica, podem ser classificados em epiteliotrópico ou não epiteliotrópico, com linhagem imunofenotípica T ou B, sendo o T mais comum. Células T reguladoras são linfócitos com capacidade imunossupressora, com papel importante na manutenção de processos fisiológicos, impedindo respostas de autoimunidade. Além disto, estudos demonstraram a influência das mesmas na supressão de respostas anti-tumorais, permitindo o escape das células neoplásicas dos mecanismos de defesa. Desta forma, o presente estudo teve como objetivo avaliar a presença das células T reguladoras em 12 cães com linfoma cutâneo T e 12 animais saudáveis, no sangue periférico e pele, através das técnicas de citometria de fluxo, avaliando porcentagens de Tregs, células T CD4+ e CD8+, e imuno-histoquímica, com a expressão tecidual de Foxp3. Observou-se maior número de Tregs no sangue periférico de cães com linfoma cutâneo (10,84±1,18) em relação aos animais saudáveis (5,67±0,89), sem diferença quanto às porcentagens de células CD4+ (48,26±4,54; 51,01±4,92, respectivamente) e CD8+ (30,32±4,82; 31,78±5,65... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Lymphoma can be characterized by clonal proliferation of malignant lymphocytes in the lymphoid organs, but may reach several tissues including the skin, called cutaneous lymphoma. In dogs, the cutaneous lymphoma may present clinically as localized or generalized lesions, wich may progress to plaque and nodules, often swollen, ulcerated and bleeding. Histologically, they can be classified as epitheliotropic or non-epitheliotropic, with immunophenotypic line T or B. Regulatory T cells are lymphocytes with immunosuppressive capacity, with a significant role in the maintenance of physiological processes, preventing autoimmunity responses. Furthermore, studies have demonstrated their influence in the suppression of anti-tumor responses, allowing the escape of neoplastic cells from the defense mechanisms. Thus, the present study aimed to evaluate the presence of regulatory T cells in 12 dogs with cutaneous T cell lymphoma and 12 healthy animals in peripheral blood and skin, through flow cytometry techniques, assessing blood concentration of Tregs, CD4+ and CD8+, and immunohistochemical, through tissue expression of Foxp3. A higher number of Tregs in the peripheral blood of dogs with cutaneous lymphoma (10,84±1,18) was observed in relation to the healthy animals (5,67±0,89), with no difference in the percentages of CD4 + (48,26±4,54; 51,01±4,92, respectively) and CD8 + (30,32±4,82; 31,78±5,65, respectively) cells. There was no difference in cellular values between the animals with ... (Complete abstract click electronic access below) / Doutor

No description available.

Orientador: Valeria Valente / Banca: Ana Lucia Fachin Saltoratto / Banca: Cleverton Roberto de Andrade / Resumo: O câncer é um conjunto de alterações celulares que favorecem a proliferação descontrolada e a aquisição de propriedades metastáticas. A ativação de oncogenes e/ou a perda de genes supressores tumorais leva a desbalanços nos mecanismos de controle do ciclo celular e/ou na inativação das vias apoptóticas, contribuindo para a instabilidade genômica presente em todos os tipos tumorais. Relatos na literatura têm sugerido que o estresse replicativo oriundo desse aumento proliferativo exacerbado é um fator importante na formação e progressão de muitos tipos de câncer. Dentro dessa perspectiva, é plausível pensar que as células tumorais tenham desenvolvido certas competências que as permitam lidar com o estresse replicativo para continuar se propagando. Resultados prévios de nosso laboratório sugerem que a proteína centromérica HJURP (Holliday Junction Recognizing Protein) esteja envolvida nesse ganho de competência. Dessa forma, esse trabalho teve como objetivo a análise do papel dessa proteína frente ao estresse replicativo em linhagens de glioblastoma. Nossos resultados demonstraram que a superexpressão de HJURP confere um aumento na capacidade proliferativa celular da linhagem U87MG. Além disso, vimos que em baixas concentrações de camptotecina as células superexpressoras de HJURP possuíam um comportamento proliferativo muito semelhante à condição não tratada. Os ensaios de citotoxicidade revelaram uma maior capacidade de recuperação frente ao estresse replicativo exógeno nas sit... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Cancer is characterized by a subset of features that supports uncontrolled cell proliferation and acquisition of metastatic properties. Oncogene activation and/ or the deactivation of tumor suppressor genes lead to disbalances in cell cycle control progression and/or inactivation of apoptotic pathways, followed by genomic instability present in all types of tumors. According to the literature, replicative DNA stress arising from uncontrolled cell growth is the major driver in the development and progression of many cancers. In this perspective, it is believed that cancer cells have developed some skills in order to deal with high levels of endogenous replicative stress for their continued proliferation. Previous results from our group suggest that the centromeric protein HJURP (Holliday Junction Recognizing Protein) is involved in this mechanism. Thus, in this work, we aimed to analyze the role of this protein in the cellular response to the replicative stress in glioblastoma U87MG cell line. Our data showed that cells who levels of HJURP were high, had an increase in cell growth. Besides that, we also observed that at lower camptothecin concentrations the curve proliferation of overexpressed HJURP cells had a similar behavior as the control cells. The cytotoxicity results demonstrated that cells overexpressing HJURP had a better replicative induced stress when compared to the control cells. Together, this data suggests... (Complete abstract click electronic access below) / Mestre

Cave (Petrochelidon fulva) and cliff swallows (Petrochelidon pyrrhonota) were collected along the Rio Grande and evaluated as potential indicators of environmental contamination. The Rio Grande receives toxic substances from agricultural, industrial, municipal, and non-point sources; consequently, high levels of contaminants have been detected in birds, mammals, fishes and sediments. Swallows were obtained from 8 sites between Brownsville and El Paso, as well as from a reference site in Burleson County, 320 miles north of the nearest site of the Rio Grande. Blood samples were analyzed by flow cytometry, a technique that allows the detection of DNA damage in blood and other tissues. Plasma samples were analyzed for thyroid hormones using a radioimmunoassay technique. Organochlorines and trace metal analysis was limited to a few samples. DDE and PCB levels were below levels known to cause reduced hatching, embryo mortality, and deformities, Hg, Pb, and As were below detection, and Se, Ni and Cr concentrations were lower than levels known to cause harm in birds. Neither species showed sex-related differences in chromosome damage. Cave swallows from the Del Rio area had the highest levels of DNA variation, which may be indicative of DNA damage, possibly from PAHs exposure. Previous studies indicate that sediment samples from tributaries near Del Rio have high levels of chromium compared to other sites along the Rio Grande. A significant increase in DNA variation between sampling years was detected in cave swallows from Llano Grande Lake. Wildlife samples collected from Llano Grande Lake have recorded high levels of DDE and PCBs; in addition, this urban/agricultural contaminant sink appears to be affected by PAH exposure. T3 levels were below the detection limit of the radioimmunoassay. There were no gender related differences in T4 levels in cave swallows. Cave swallows sampled from Laredo had significantly higher T4 levels than those from birds at other sites during 1999. It was not possible to determine thyroid hormone disruption in plasma samples. Thyroid hormone and flow cytometry data were useful in establishing baseline data. Areas of concern based on genotoxic data include Llano Grande Lake, Del Rio, and El Paso.

Population dynamics of picophytoplanktons, including Prochlorococcus, Synechococcus, and picoeukaryotes, were investigated in the upstream Kuroshio. Data were collected during eight cruises between July 2007 and May 2009. Sampling stations were located along 21¢X55¡¦N and between 121¢X00¡¦E and 122¢X10¡¦E in the Kuroshio off the Southeast Taiwan. Monitoring experiments including light shadding experiment, nutrient enrichment, temperature control, and grazing experiments were conducted to better understand the mechanisms that affect the growths of the picophytoplanktons. The abundances of the picophytoplanktons were measured using a flow cytometry.Water column integrated (0~200 m) abundance of Prochlorococcus was higher (26.63 ¡Ó 3.87 ¡Ñ 1012 cells m-2) in spring than either summer (19.07 ¡Ó 4.08 ¡Ñ 1012 cells m-2), autumn (16.05 ¡Ó 2.80 ¡Ñ 1012 cells m-2), or winter (17.89 ¡Ó 5.41 ¡Ñ 1012 cells m-2). During winter, the abundance was significantly (p<0.05) higher at the offshore station (17.89 ¡Ó 5.41 ¡Ñ 1012 cells m-2) than the inshore station (3.19 ¡Ó 2.07 ¡Ñ 1012 cells m-2). The abundance of Prochlorococcus was positively related to water temperature, nitracline depth (Dni), and euphotic depth (Deu), and negatively to surface concentration of N+N or SRP. Prochlorococcus was abundant (>100 ¡Ñ 103 cells ml-1) in the upper 100-m water column. Its maximum (200~300 ¡Ñ 103 cells ml-1) often occurred at the depth shallower than 75 m. The cell density sustained at >25 ¡Ñ 103 cells ml-1 between 100~150 m and was almost nil at the depth deeper than 150 m. There was no significant seasonal differences for either the abundances of Synechococcus (0.32~1.07 ¡Ñ 1012 cells m-2) or picoeukaryotes (0.16~0.24 ¡Ñ 1012 cells m-2). During winter, the abundances of Synechococcus was significantly (p<0.05) higher in the offshore Kuroshio water (2.94 ¡Ó 0.32 ¡Ñ 1012 cells m-2) than that of the inshore Kuroshio water. Similar trend of offshore (0.52 ¡Ó 0.05 ¡Ñ 1012 cells m-2) higher than the inshore was observed for picoeukaryotes in winter. The dynamics of Synechococcus abundance was positively related to surface SRP concentration and negatively to Dni. The picoeukaryotes abundance was positively related to surface N+N concentration, and SRP and negatively to Temp, Dni, and Deu. Vertical distribution of Synechococcus showed that the maximum abundance often occurred above 75 m, but was almost nil below 100 m. By contrast, the maximum abundance for picoeukaryotes often occurred between 50~125 m. The abundance of Synechococcus was positively related to the abundance of picoeukaryotes. And their abundance were negatively related to that of Prochlorococcus. Many environmental factors fluctualed parallelly. Dynamics of surface Temp, Dni and Deu were positively correlated to each other and either of them was negatively correlated to the dynamics of surface concentration of N+N or SRP. Surface N+N was positively correlated with surface SRP. The result of light shadding experiment showed that Prochlorococcus and picoeukaryotes, compared to Synechococcus, were much sensitive to high intensity of light. This suggest that Synechococcus was more tolerant to high light intensity or required more light energy than Prochlorococcus or picoeukaryotes. The results of nutrient enrichment experiments showed that addition of EDTA significantly enhanced the growth of three groups of picophytoplanktons. However, there was no significant difference after addition of either nitrate, Fe, or Cu. Prochlorococcus grew better at 27 ¢XC than 30 ¢XC in the temperature experiment. But there was no difference in the growth rate between 27 ¢XC and 30 ¢XC for Synechococcus or picoeukaryotes The result of grazing experiment showed that there was no difference between the growth rate with and without grazers in the incubation for any of the three groups of picophytoplanktons.

Cave (Petrochelidon fulva) and cliff swallows (Petrochelidon pyrrhonota) were collected along the Rio Grande and evaluated as potential indicators of environmental contamination. The Rio Grande receives toxic substances from agricultural, industrial, municipal, and non-point sources; consequently, high levels of contaminants have been detected in birds, mammals, fishes and sediments. Swallows were obtained from 8 sites between Brownsville and El Paso, as well as from a reference site in Burleson County, 320 miles north of the nearest site of the Rio Grande. Blood samples were analyzed by flow cytometry, a technique that allows the detection of DNA damage in blood and other tissues. Plasma samples were analyzed for thyroid hormones using a radioimmunoassay technique. Organochlorines and trace metal analysis was limited to a few samples. DDE and PCB levels were below levels known to cause reduced hatching, embryo mortality, and deformities, Hg, Pb, and As were below detection, and Se, Ni and Cr concentrations were lower than levels known to cause harm in birds. Neither species showed sex-related differences in chromosome damage. Cave swallows from the Del Rio area had the highest levels of DNA variation, which may be indicative of DNA damage, possibly from PAHs exposure. Previous studies indicate that sediment samples from tributaries near Del Rio have high levels of chromium compared to other sites along the Rio Grande. A significant increase in DNA variation between sampling years was detected in cave swallows from Llano Grande Lake. Wildlife samples collected from Llano Grande Lake have recorded high levels of DDE and PCBs; in addition, this urban/agricultural contaminant sink appears to be affected by PAH exposure. T3 levels were below the detection limit of the radioimmunoassay. There were no gender related differences in T4 levels in cave swallows. Cave swallows sampled from Laredo had significantly higher T4 levels than those from birds at other sites during 1999. It was not possible to determine thyroid hormone disruption in plasma samples. Thyroid hormone and flow cytometry data were useful in establishing baseline data. Areas of concern based on genotoxic data include Llano Grande Lake, Del Rio, and El Paso.

Thesis (Ph. D.)--University of Washington, 2003. / Vita. Includes bibliographical references (leaves 179-191).

The antibody Fc region is critical for the therapeutic potency by virtue of its role in recruiting and activating the cytotoxic pathways of immune cells, complement activation and its role in antibody homeostasis (a process mediated by the pH dependent binding to the neonatal receptor FcRn). Bacterially produced antibodies lack of glycosylation at Asn297 and therefore do not bind to the surface Fc[gamma]Rs on effector innate immune cells, nor can they activate complement. This dissertation describes the engineering of aglycosylated bacterially expressed antibodies for binding to a specific Fc[gamma]R and therefore eliciting therapeutically relevant effector functions. Aglycosylated Fc mutants that bind to desired Fc binding ligands were isolated by a new E. coli homodimeric Fc display system coupled with high throughput flow cytometry. Two amino acids mutation in the CH3 domain (Fc5) conferred selectively high binding affinity of aglycosylated Fc domains to the Fc[gamma]RI receptor. Flow cytometry screening from a randomized Fc5 library resulted in the isolation of Fc mutants exhibiting higher affinity binding to Fc[gamma]RI receptor than the Fc5. Aglycosylated Fc[gamma]RI specific IgG containing the variable regions of the clinically important anti-Her2 antibody trastuzumab elicited dendritic cell-mediated ADCC in sharp contrast to the clinical grade trastuzumab (Herceptin) or the glycosylated coutreparts of the engineered antibodies, neither of which could potentiate target cell lysis with dendritic cells as effectors. In separate studies, a system was developed for the screening of periplasmically anchored E. coli libraries and the isolation of clones expressing antibodies that are specific to insoluble antigens or to cell surface markers. Following three rounds of flow cytometric screening, spheroplasts expressing specific scFvs were enriched 950-fold from a large excess (1,000x) of spheroplasts expressing nonspecific antibodies. / text