Orientador: Wilma De Gravas Kempinas / Banca: Raquel Fantin Domeniconi / Banca: Estela Saao Cerri / Resumo: Interferons (IFNs) são pequenas proteínas conhecidas por suas atividades antiproliferativa e imunorregulatória e por seu envolvimento crucial na ação antiviral celular. Os IFNs do tipo I incluem os IFN-α, β e ω e são utilizados terapeuticamente no tratamento de diversos tipos de cânceres e hepatites B e C. Sabe-se que dentre os efeitos adversos causados pelo IFN-α estão as disfunções endócrinas. Pouco se sabe sobre os efeitos dos IFNs na reprodução. Assim, o presente estudo objetivou investigar, em ratos adultos, os efeitos da exposição subcrônica a diferentes doses de IFN-α sobre parâmetros reprodutivos masculinos. No experimento 1, ratos Wistar adultos (90 dias/350-470g) foram distribuídos em três grupos experimentais (n=10), sendo um controle, cujos animais receberam o veículo, e dois tratados, subcutaneamente, com as doses de 5x104 unidades/Kg e 10x104 unidades/Kg, diluídas em salina. Após 30 dias de tratamento os animais foram pesados e eutanasiados para coleta dos órgãos do sistema genital. Testículo e epidídimo direitos, próstata ventral e glândula seminal (sem a glândula coaguladora) de cada animal foram retirados e pesados. Testículos e epidídimos direitos foram utilizados para determinação do número de células germinativas e os epidídimos esquerdos para a coleta de espermatozoides para avaliação da motilidade e morfologia espermática e para serem usados nas inseminações artificiais intrauterinas. Os níveis séricos de testosterona também foram mensurados. No experimento 2, outro lote de animais, seguindo o mesmo design experimental, foi utilizado para a coleta dos testículos e epidídimos esquerdos para avaliações histopatológica e morfométrica. Os pesos corpóreos e dos órgãos reprodutores foram semelhantes entre os grupos, bem como a produção espermática diária, tempo de trânsito espermático através do epidídimo, motilidade e morfologia ... / Abstract: Interferons (IFNs) are small proteins known their antiproliferative and immunoregulatory activities and their crucial involvement in the cellular antiviral. Type I IFNs include the IFN-α, β e ω and are used therapeutically in the treatment of several kinds of cancers and hepatitis B and C. Endocrine dysfunction is among the adverse side effects of IFN-α. Little is know about the effects of IFNs on reproduction. Therefore, the present study aimed to investigated, in adult rats, the effects of subchronic exposure to different doses of IFN-α on male reproductive parameters. In the experiment 1, adult male Wistar rats (90 days/350-470g) were distributed in three experimental groups (n=10), one control, which received the vehicle, and two treated, subcutaneously, with 5x104 units/Kg e 10x104 units/Kg of IFN-α, diluted in saline. After 30 days of treatment the animals were weighed and euthanized for collection of reproductive organs. Right testis and epididymis, ventral prostate and seminal gland (without coagulating gland) of each animal were removed and weighed. Right testis and epididymis were used for the determination of sperm number and left epididymis for collection of sperm to evaluate of sperm motility and morphology and for intrauterine artificial insemination. The serum testosterone levels were also measured. In the experiment 2, another lot of animals, following the same experimental design, were used for collection of left testis and epididymis for to histopathological and morphometric evaluation. The body and reproductive organ weights were unchanged, as well as the daily sperm production, sperm transit time through the epididymis, sperm motility and morphology and fertility potential of animals. The histopathological and morphometric evaluation did not reveal injuries related to treatment. Thus, our results show that subchronic exposure to IFN-α did not interfere with levels of serum testosterone ... / Mestre

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Gastric cancer is the second leading cause of cancer death worldwide and in China. The mechanism of gastric carcinogenesis is not fully understood. Epigenetic studies indicated that inactivation of tumor suppressor genes by DNA hypermethylation plays a crucial role in the progression of gastric cancer. Epigenetic inactivation of secreted frizzled-related protein (SFRP 1) by methylation plays a pivotal role on the development of various cancers. However, the role of SFRP family genes in gastric cancer remains largely unknown. We aimed to characterize the epigenetic abnormalities and discover novel biomarkers for early detection of gastric cancer. We investigated the epigenetic alterations in gastric adenocarcinoma by microarray based analysis and gene promoter hypermethylation. Based of the microarray data, we determined the functional significance and frequency of SFRP family genes hypermethylation in human gastric cancer. We screened the mRNA expression and methylation status of the SFRP family members in human gastric cancer cell lines and primary gastric cancer samples. Demethylation study of SFRP family genes were done by treating gastric cancer cell lines with 5'Aza. The biological effects of SFRP were analyzed by flow cytometry, cell viability assay and tumor growth in nude mice. SFRP1, 2, 4 and 5 were undetectable in 100% (7/7), 100% (7/7), 42.8% (3/7) and 85.7% (6/7) of gastric cancer cell lines, respectively. However, only SFRP2 showed significant down-regulation in gastric cancer compared with adjacent non-cancer samples (P<0.01). Treatment with demethylation agent, 5'-Aza, restored the expression of SFRP2 in all 7 cancer cell lines. Promoter hypermethylation of SFRP2 was detected in 73.3% of primary gastric cancer samples and 20% of adjacent non-cancer tissue (P<0.01). Bisulfite sequencing confirmed the density of promoter methylation in cell line, primary gastric cancer tissue and their adjacent non-cancer tissue. Transfection of SFRP2 induced cell apoptosis, inhibited proliferation in vitro and suppressed tumor growth in vivo. Furthermore, SFRP2 methylation was detected in 37.5% of samples showing intestinal metaplasia. Methylated SFRP2 was also detected in 66.7% of serum samples from cancer patients but not in normal controls. Epigenetic inactivation of SFRP2, but not SFRP1, SFRP4 and SFRP5 is a common and early event of carcinogenesis. Hence, detection of SFRP2 methylation in serum may have diagnostic value in gastric cancer patients. / by Cheng, Yuen Yee. / Adviser: FKL Chan. / Source: Dissertation Abstracts International, Volume: 69-02, Section: B, page: 0803. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2007. / Includes bibliographical references (leaves 165-179). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese. / School code: 1307.

Aim. In this study, we attempted to identify HCC-specific serum glycoproteins by using glycoproteomic technologies. We targeted at finding glycoforms with aberrant alpha-2,6-sialylation and alpha-1,6-fucosylation in sera of HCC patients. These glycoforms may have potentials to be used as tumor marker(s) in the diagnosis of HCC. / Among the validated differential glycoproteins, Hp was the only glycoprotein, glycoforms of which were found to be significantly up-regulated in the HCC group when examining both the sialylated glycoprotein profiles and the fucosylated glycoprotein profiles. This glycoprotein was selected for further investigation. In the independent validation group, increased serum levels of Hp (total), alpha-2,6 sialylated Hp and alpha-1,6 fucosylated Hp was observed in the HCC patients. A unique pattern of Hp glycoforms comprising both hypersialylated fucosylated and hyposialytated fucosylated species was found in the HCC patients. Serum concentrations of these glycoforms were significantly higher in the HCC patients with advanced tumor, suggesting their tumor-specific nature. Besides, we have performed quantitative profiling of N-glycans of serum Hp in the HCC patients, CLD patients and normal subjects, and have attempted to identify HCC-associated N-glycans for HCC diagnosis. Combined used of serum alpha-fetoprotein, serum Hp and its N-glycans, we could achieve 84% sensitivity at 100% and 93% specificities when distinguishing the HCC patients from the CLD patients and from the normal subjects, respectively. / Background. Hepatocellular carcinoma (HCC) often arises in patients with coexisting chronic liver disease (CLD). Since alpha-fetoprotein, a conventional biomarker, may also be raised in patients with uncomplicated CLD, the use of alpha-fetoprotein in early detection of HCC is limited. Identification of additional biomarkers may improve early detection. Previous studies have shown that levels of alpha-2,6-sialyltransferase and alpha-1,6-fucosyltransferase change in liver cancer, leading to aberrant glycosylations on some serum proteins. / Conclusion. By undertaking glycoproteomic approach, we have identified a panel of potential biomarkers for diagnosis of HCC. These biomarkers were useful for classifying among normal healthy subjects, CLD patients, patients with early HCC and patients with advanced HCC. Some of them were validated with the independent cases. Finally, we have identified a unique pattern of Hp glycoforms comprising both hypersialylated fucosylated and hyposialylated fucosylated species in the HCC patients. Serum Hp and its N-glycans have been shown to have potential values for aiding the diagnosis of HCC. / Methodology. There are four parts in this study. The first part is "method development". A method for obtaining quantitative profiles of serum glycoproteins with alpha-2,6-sialylation or alpha-1,6-fucosylation was developed by combined use of lectin affinity chromatography, two-dimensional polyacrylamide gel electrophoresis and enzyme-linked lectin assay. The second part is "biomarker discovery". The quantitative profiles of the serum glycoproteins from 20 HCC patients and 10 CLD patients (control) were compared by bioinformatic approaches to identify potential biomarkers for diagnosis of HCC. The protein identities of the potential targets were obtained by using MALDI-TOF/TOF mass spectrometry. The third part is "validation". An independent set of serum samples from 40 HCC patients, 30 CLD patients and 20 normal subjects was used to evaluate the diagnostic values of the potential biomarkers. The last part of this study was aimed to identify HCC-associated N-glycans on one of potential biomarkers found, and examine their values in diagnosis of HCC. / Result. When analyzing alpha-2,6-sialylated glycoproteins, 53 glycoprotein spots were significantly different between the HCC and CLD groups, of which 44 spots belonged to 13 glycoproteins. Bioinformatic analyses revealed that these differential sialoglycoprotein profiles contained valuable information for differentiating the HCC patients from CLD patients, and classifying between early HCC and advanced HCC patients. When analyzing alpha-1,6-fucosylated proteins, 11 glycoprotein spots were significant different between the two study groups, of which 8 spots belonged to 1 glycoprotein. Majority of the protein identities were successfully obtained by MALDI-TOF/TOF mass spectrometry. Among the differential glycoproteins, we have identified a subgroup with a unique pattern of glycosylation. These glycoproteins were characterized by the presence of hypersialylated and fucosylated glycoforms. The differential patterns and the diagnostic values of some of these serum glycoproteins were confirmed in the independent validation group by measuring their serum levels with immunoassays. The results of the logistic regression analyses suggest that complement factor B and haptoglobin (Hp) can be used in combination with alpha-fetoprotein to improve the diagnosis of HCC. / Ang, Ling. / Adviser: Tereng Chuen Wai Poon. / Source: Dissertation Abstracts International, Volume: 69-02, Section: B, page: 0947. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2007. / Includes bibliographical references (leaves 215-238). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese. / School code: 1307.

Made available in DSpace on 2014-10-09T12:55:25Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:06:02Z (GMT). No. of bitstreams: 0 / Dissertação (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP

Made available in DSpace on 2014-10-09T12:55:25Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:06:02Z (GMT). No. of bitstreams: 0 / Neste trabalho é descrito um método prático e eficiente para dissociar, em subunidades &alpha; e &beta;, quantidades pequenas (da ordem de microgramas) dos hormônios foliculotrofina (hFSH), luteotrofina (hLH) e tireotrofina (hTSH) humana, nativos e recombinantes. A dissociação destes hormônios foi conseguida incubando-os, durante 16 horas, a 37ºC, com diferentes concentrações de ácido acético: 3M, 5M e 0,4M respectivamente para o hFSH, hLH e hTSH. Nestas condições, uma eficiência de dissociação acima de 98% foi obtida. Esta eficiência foi calculada com base nas determinações de massa dos heterodímeros e das subunidades, realizadas por MALDI-TOF-MS. Uma separação rápida e quantitativa das subunidades, com rendimentos da ordem de 80-90%, foi conseguida por cromatografia líquida de alta eficiência em fase reversa (RP-HPLC) em uma coluna C4. As subunidades foram caracterizadas quanto à pureza, hidrofobicidade, massa molecular e distribuição de carga por HPLC de exclusão molecular e fase reversa, SDS-PAGE e focalização isoelétrica. Quando analisadas quanto à hidrofobicidade, as subunidades mostraram-se aproximadamente iguais, enquanto as subunidades &beta; dos três heterodímeros apresentaram a seguinte escala de hidrofobicidade: &beta;-hFSH < &beta;-hTSH < &beta;-hLH. Com relação à massa molecular relativa (Mr), as subunidades &alpha; e &beta; do hFSH apresentaram as maiores Mr enquanto as subunidades do hLH as menores. A distribuição dos isômeros de carga das subunidades dos três hormônios ocorreu em uma região ácida, para o hFSH, em uma região básica, para o hLH e em uma região intermediária, para o hTSH. As subunidades &alpha; dos três hormônios, quando analisadas via SDS-PAGE, apresentaram praticamente a mesma mobilidade eletroforética, enquanto as subunidades &beta; apresentaram diferentes taxas de migração (mR), sendo mR &beta;-hFSH < mR &beta;-hTSH < mR &beta;-hLH. Diferenças relativas à massa molecular, hidrofobicidade, migração eletroforética e distribuição de carga foram encontradas entre as preparações recombinantes e hipofisárias dos três hormônios. O método descrito é suave, prático e flexível e pode ser adaptado à dissociação de outras glicoproteínas heterodiméricas recombinantes ou nativas. Permite não só estudos e caracterização direta de cada subunidade, como também detectar a presença de subunidades livres em preparações farmacêuticas, que são contaminantes indesejáveis, sendo, portanto, uma ferramenta extremamente útil para o controle de qualidade de produtos farmacêuticos. / Dissertação (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP

Colonic epithelial glycoproteins were histochemically studied in rats during the induction of colorectal cancer with 1,2,-dimethylhydrazine-diHCl (DMH). 310 male Wistar rats were separated into 3 groups: 10 control rats were sacrificed without treatment, 150 rats were given weekly subcutaneous injections of the carcinogen and 150 rats were given sham Injections on the same schedule. Groups of rats (10 control and 10 treated) were sacrificed at various time intervals in an effort to obtain a large number of pre-neoplastic rat colons to be used to determine whether histochemical changes could be detected prior to morphologic change. Three histochemically distinct regions in the Wistar rat distal colon have been described using recently developed techniques. Two major histochemical changes have been shown to occur prior to malignancy. Change 'A' represented a decrease or loss of sulphate from the glycoproteins; this was the earliest and predominant change and has been shown to occur prior to any identifiable morphologic change. Change 'B' represented a decrease or loss of sulphate occurring in the same cells as a decrease or loss of side chain 0-acetylation of sialic acid residues; this change occured later and to a lesser extent than change 'A'. The data suggests that histochemical change may be a premalignant marker, however, further investigations are necessary to firmly establish this conclusion. / Medicine, Faculty of / Pathology and Laboratory Medicine, Department of / Graduate