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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

An investigation into the biology of seminoma

Eastwood, Deborah Jane January 1999 (has links)
No description available.
12

Downregulation of miRNA expression in malignant germ cell tumours : mechanism and functional significance

Ferraresso, Marta January 2019 (has links)
Germ cell tumours (GCTs) are clinically and pathologically heterogeneous neoplasms that arise at gonadal (testicular/ovarian) and extra-gonadal sites. The chemotherapy burden for patients with malignant germ cell tumours (mGCTs) that require treatment results in substantial longterm side-effects, and, furthermore, poor-risk patients have < 50% survival. Consequently, identifying common molecular changes and novel therapeutic targets in mGCTs is of major clinical importance. MicroRNAs are short, non-protein coding RNAs that regulate gene expression. We previously showed that miR-99a-5p/-100-5p and miR-125b-5p are among the most frequently underexpressed microRNAs in mGCTs, regardless of anatomical site, histological type or patient age. The present study investigates the upstream causes and downstream consequences of such under-expression. The mature form of miR-125b-5p is the product of two genomic loci, which form a cluster with either miR-99a-5p (on chromosome 21q) or miR-100-5p (on chromosome 11q). MiR-99a-5p/- 100-5p share identical 'seed' regions (at nucleotide positions 2-7), which determine their mRNA targets. Cross-reactivity experiment revealed that both miR-99a-5p and miR-100-5p probes were highly cross-reactive to each other's target (from 91% to 95%), indicating functional overlap. Linear regression analysis of qRT-PCR data reveals a strong positive correlation between miR-99a-5p/-100-5p and miR-125b-5p levels (R2 =0.989) in mGCTs, strongly suggesting co-regulation. Primary microRNA transcripts (pri-miR-99a/-100 and pri-miR-125b), and other genes that colocalise to these miRNA clusters (e.g. BLID on chromosome 11), were quantified by RT-qPCR in four representative cell lines - TCam2, 1411H, 2102Ep, and GCT44 - which were derived from a range of common histological types of mGCTs. A significant down-regulation (p < 0.0001) of all primary transcripts was observed, suggesting transcriptional repression of the entire cluster regions. Treatment of the cell lines with 5'-azacytidine resulted in significant upregulation of all three miRNAs (p < 0.002), as well as BLID (p < 0.02). The methylation status of potential CpG islands at the region of interest on chromosome 11 and chromosome 21 was therefore investigated by Pyrosequencing. Significant hyper methylation was found in 2102Ep, 1411H and GCT44 cell lines, suggesting that the miR-99a-5p/-100-5p and miR-125b-5p clusters are likely transcriptionally silenced by DNA methylation. To assess the functional relevance of these microRNAs in GCT progression, co-transfection of microRNA mimics (8.3 nM miR-99a-5p/-100-5p + 8.3 nM miR-125b-5p) was performed. A significant decrease in cell growth was seen in 1411H (p < 0.01) and TCam2 (p < 0.03) cells. To identify the mimics' downstream mRNA targets, HumanHT-12 v4 Expression Bead Chip (Illumina) mRNA arrays were used and data analysed using Sylamer. This analysis showed that mimic-treated cells were enriched in downregulated genes involved in pro-proliferative mechanisms. Among those, further functional characterisation focussed in particular on TRIM71, FGFR3, E2F7 and LIN28A. Moreover, restoring miR-99a-5p/-100-5p and miR-125b-5p in TCam2 cells also resulted in G0-G1 accumulation, consistent with a cell cycle effect. These data support a functionally important role for miR99a-5p/-100-5p and miR-125b-5p in GCT progression. They also raise the possibility of a therapeutic replenishment approach for treating these, and potentially other, tumours.
13

Tumores testiculares germinativos não-seminomas imunoexpressão protéica de EGFR, Her2 E c-Kit /

Quevedo, Francisco Carlos January 2017 (has links)
Orientador: Maria Aparecida Custodio Domingues / Resumo: As neoplasias testiculares constituem aproximadamente 1% dos cânceres masculinos. Dentre eles, os tumores que têm origem nas células germinativas (TTCG) são os mais frequentes. Por sua natureza, esses tumores têm padrão morfológico variado, sendo distribuídos em dois subgrupos: os seminomas e os não-seminomas. Esses últimos, por sua vez, são classificados em carcinomas embrionários, tumores do seio endodérmico, coriocarcinomas, teratomas e tumores mistos de células germinativas. Há consenso na literatura de que a invasão vascular verificada histologicamente no tumor primário é o melhor indicador preditivo de progressão da doença e recidiva. Estudos recentes demonstram o papel dos fatores de crescimento e seus receptores para avaliação prognóstica dos TTCG, no que o uso da imuno-histoquímica é fundamental. O presente estudo procurou avaliar pela técnica imuno-histoquímica à ocorrência da expressão do receptor do fator de crescimento epidérmico (EGFR), do Her2 e do c-Kit em uma série de TTCG não-seminomas primários de testículo. Além disso, explorou a possível relação entre a expressão desses marcadores com a evolução dos pacientes após terapêutica convencional. A série foi constituída de amostras parafinadas existentes no Laboratório de Anatomia Patológica e Citologia do Hospital Amaral Carvalho de Jaú, totalizando 103 pacientes que receberam o diagnóstico de tumor testicular de células germinativas não-seminomas (TTCGNS) no período 1996-2010. Dentre os 103 casos, predominaram... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Testicular neoplasms constitute approximately 1% of male cancers. Among these, germ cell tumors (TGCT) are the most prevalent. These tumors show varied morphological patterns and are distributed into two subgroups: seminomas and non-seminomas. The latter, in turn, are classified as embryonal carcinomas, endodermal sinus tumors, choriocarcinomas, teratomas and mixed germ cell tumors. The consensus in the literature is that histological verification of vascular invasion (VI) in the primary tumor is the best predictor of disease progression and recurrence. However, recent studies have highlighted the role of growth factors and their receptors for prognostic evaluation of TGCT, in which the use of immunohistochemistry is fundamental. This study sought to evaluate the occurrence of epidermal growth factor receptor (EGFR), Her2 and c-Kit in a series of primary non-seminoma TGCTs. In addition, possible relationships between the expression of these markers and patient evolution following conventional therapy was investigated. The series consisted of paraffin-embedded samples from the Laboratory of Anatomical Pathology and Cytology of Amaral Carvalho Hospital in Jaú, SP, Brazil, of 103 patients diagnosed with testicular non-seminoma germ cell tumor (NSGCT) over a 15-year period (1996-2010). Among the 103 cases, testicular NSGCT predominated (57.3%), and among these, staining for EGFR and c-Kit predominated. EGFR was expressed when the choriocarcinoma component was predominant, and c-K... (Complete abstract click electronic access below) / Doutor
14

Tumores testiculares germinativos não-seminomas: imunoexpressão protéica de EGFR, Her2 E c-Kit / Non seminomatous testicular germ cell tumors: EGFR, Her2 and c-Kit imunoexpression

Quevedo, Francisco Carlos [UNESP] 25 August 2017 (has links)
Submitted by FRANCISCO CARLOS QUEVEDO null (fcqjau@gmail.com) on 2017-09-15T16:19:40Z No. of bitstreams: 1 _TTCG FINAL 260715 FCQ [2].pdf: 2024513 bytes, checksum: 9e2b5af27bf3e7a02eb1625af9c3c0fc (MD5) / Approved for entry into archive by Luiz Galeffi (luizgaleffi@gmail.com) on 2017-09-15T16:27:51Z (GMT) No. of bitstreams: 1 quevedo_fc_dr_bot.pdf: 2024513 bytes, checksum: 9e2b5af27bf3e7a02eb1625af9c3c0fc (MD5) / Made available in DSpace on 2017-09-15T16:27:51Z (GMT). No. of bitstreams: 1 quevedo_fc_dr_bot.pdf: 2024513 bytes, checksum: 9e2b5af27bf3e7a02eb1625af9c3c0fc (MD5) Previous issue date: 2017-08-25 / As neoplasias testiculares constituem aproximadamente 1% dos cânceres masculinos. Dentre eles, os tumores que têm origem nas células germinativas (TTCG) são os mais frequentes. Por sua natureza, esses tumores têm padrão morfológico variado, sendo distribuídos em dois subgrupos: os seminomas e os não-seminomas. Esses últimos, por sua vez, são classificados em carcinomas embrionários, tumores do seio endodérmico, coriocarcinomas, teratomas e tumores mistos de células germinativas. Há consenso na literatura de que a invasão vascular verificada histologicamente no tumor primário é o melhor indicador preditivo de progressão da doença e recidiva. Estudos recentes demonstram o papel dos fatores de crescimento e seus receptores para avaliação prognóstica dos TTCG, no que o uso da imuno-histoquímica é fundamental. O presente estudo procurou avaliar pela técnica imuno-histoquímica à ocorrência da expressão do receptor do fator de crescimento epidérmico (EGFR), do Her2 e do c-Kit em uma série de TTCG não-seminomas primários de testículo. Além disso, explorou a possível relação entre a expressão desses marcadores com a evolução dos pacientes após terapêutica convencional. A série foi constituída de amostras parafinadas existentes no Laboratório de Anatomia Patológica e Citologia do Hospital Amaral Carvalho de Jaú, totalizando 103 pacientes que receberam o diagnóstico de tumor testicular de células germinativas não-seminomas (TTCGNS) no período 1996-2010. Dentre os 103 casos, predominaram os TTCGMNS (57,3%). Nestes, observou-se o predomínio de marcação para EGFR e c-Kit. O EGFR foi expresso quando o componente coriocarcinoma era predominante e o c-Kit no componente epitelial do teratoma. A hipótese do estudo, que os casos positivos para os marcadores analisados estariam correlacionados com sobrevida menor, não foi confirmada pela analise estatística de Kaplan-Meier; seria necessário um maior número de casos para se chegar a uma conclusão quanto à sobrevida. Superexpressão, amplificação gênica e mutações ativadoras são frequentes em tumores testiculares germinativos; deste modo, o uso da técnica de Hibridização Fluorescente in situ (FISH) foi utilizada para avaliação dos eventos gênicos relativos a imunoexpressão proteica, observada pelos resultados encontrados no estudo imuno-histoquímico. Somente um caso, classificado como TTCGM, apresentava amplificação para gene EGFR. Este caso apresentou bom prognóstico. Considerou-se que, a ausência de amplificação observada na maioria dos casos, deve-se a qualidade inadequada do material parafinado e estocado. Conclui-se que, na série estudada, os TTCGNS expressam os marcadores EGFR, Her2 e c-Kit, a depender do subtipo histológico; entretanto, estas proteínas não tiveram impacto prognostico. A amplificação gênica para o EGFR pode ocorrer de forma isolada, porem devido a condições técnicas restritivas, não foi possível observa-la nos demais casos positivos para EGFR pela técnica de imuno-histoquímico. / Testicular neoplasms constitute approximately 1% of male cancers. Among these, germ cell tumors (TGCT) are the most prevalent. These tumors show varied morphological patterns and are distributed into two subgroups: seminomas and non-seminomas. The latter, in turn, are classified as embryonal carcinomas, endodermal sinus tumors, choriocarcinomas, teratomas and mixed germ cell tumors. The consensus in the literature is that histological verification of vascular invasion (VI) in the primary tumor is the best predictor of disease progression and recurrence. However, recent studies have highlighted the role of growth factors and their receptors for prognostic evaluation of TGCT, in which the use of immunohistochemistry is fundamental. This study sought to evaluate the occurrence of epidermal growth factor receptor (EGFR), Her2 and c-Kit in a series of primary non-seminoma TGCTs. In addition, possible relationships between the expression of these markers and patient evolution following conventional therapy was investigated. The series consisted of paraffin-embedded samples from the Laboratory of Anatomical Pathology and Cytology of Amaral Carvalho Hospital in Jaú, SP, Brazil, of 103 patients diagnosed with testicular non-seminoma germ cell tumor (NSGCT) over a 15-year period (1996-2010). Among the 103 cases, testicular NSGCT predominated (57.3%), and among these, staining for EGFR and c-Kit predominated. EGFR was expressed when the choriocarcinoma component was predominant, and c-Kit when the epithelial component of the teratoma was predominant. The initial hypothesis that positive cases for any marker would be correlated to lower survival was not confirmed by Kaplan-Meier survival probability studies. A larger number of cases is required to reach any conclusions concerning survival. Gene overexpression and amplification and activating mutations are common in testicular germinal tumors, thus fluorescent in situ hybridization (FISH) was used to validate the genic events results obtained in the immunohistochemical study. Only one case, classified as mixed TGCT, showed EGFR gene amplification, and this case presented good prognosis. The lack of amplification observed in most cases was due to the inadequate quality of the stored, paraffinembedded materials. In conclusion, in the series studied, testicular NSGCT expressed EGFR, Her2 and c-Kit markers depending on the histological subtype; however, these proteins had no prognostic impact. Gene amplification for EGFR may occur in isolation, but due to the limited technical conditions, it was not observed in the other cases positive for EGFR using immunohistochemistry.
15

Development and use of an in vitro technique to investigate the effect of pharmaceutical agents on female germ cell development

Stefansdottir, Agnes January 2015 (has links)
With meiosis spanning from embryonic development to the end of reproductive life in females, scientists have faced considerable limitations in studying female meiosis and the effects of toxicants on the developing oocyte. Over the last half century, various culture methods have been developed with the aim of studying the mechanisms of early ovary development, as well as for use in reproductive toxicology. However, very few of the established embryonic ovary culture systems have been used to investigate potential reproductive toxicants on the embryonic ovary, in particular when compared with the vast number of in vitro reproductive toxicity studies on the post-natal ovary. Here, a novel test compound, a topoisomerase II inhibitor: AstraZeneca Test Compound (AZTC), was used to investigate the efficacy and validity of ovarian culture methods when compared with in vivo reprotoxicity studies. AZTC was selected due to preliminary in vivo studies demonstrating its detrimental effects on spermatogenesis in male rats. AZTC targets bacterial type II topoisomerases that might have mammalian homologues involved in meiosis. Topoisomerase-II α was expressed within the female germ cells pre-natally, but became localised to the granulosa and stroma cells post-natally. This occurred both in vivo and in vitro. Ovaries from female rats exposed pre-natally to AZTC in vivo were analysed histologically and a significant increase in the number of primordial follicles was observed within the ovaries, as well as an increase in the number of unhealthy follicles. A novel mouse embryonic ovary culture system was developed by adapting, improving and bridging existing available culture techniques. The culture system supported growth of pre-meiotic mouse germ cells through prophase I of meiosis, the formation of primordial follicles and initiation of follicle growth. Cultured ovaries contained follicles at stages in comparable ratios to those in vivo and appeared morphologically normal and healthy. The culture also supported meiotic progression of oocytes to the pachytene stage, albeit with a slight delay. AZTC was used to validate the novel embryonic ovary culture by comparing the results with those from the in vivo study, where AZTC exposure had also occurred during embryonic development. Similar results were consistently observed between the in vivo and in vitro studies. In vitro effects of AZTC on the post-natal mouse ovary were also investigated, where neonatal mouse ovaries cultured with AZTC had fewer primordial follicles and more unhealthy follicles than did control ovaries. AZTC therefore demonstrated different effects when exposure occurred pre-natally vs. post-natally. The embryonic ovary culture was then used to examine the effects of another topoisomerase II inhibitor, etoposide, on the pre-natal ovary. Etoposide is a chemotherapy agent and has previously been prescribed to pregnant women. A significant reduction in the size of the follicle pool was observed in exposed cultured embryonic ovaries, where primordial and transitional follicles were targeted. Overall, establishment of post-natal culture systems have become a useful addition to in vivo reproductive toxicology studies. The embryonic ovary culture system developed here could become a valuable and powerful tool to screen potential reproductive toxicants, as well as to study the dynamics and regulation of early ovary development.
16

Germ Cell Tumor and Takotsubo Cardiomyopathy: A Treatment Dilemma

Hannan, Abdul, Khalid, Muhammad Faisal, Yasmeen, Samia 01 July 2018 (has links)
Germ cell tumors (GCT) are uncommon malignancies in adult males and comprise less than 1% of male cancers. Due to highly curative nature and productive life years gained after treatment; reduction of chemotherapy related toxicities becomes vital. Cisplatin is the backbone of GCT chemotherapy, & is related to myocardial injury, thromboembolism & vasculitis. Though it should not be replaced with Carboplatin, however in certain circumstances, its use maybe unsafe; especially in cases when patient have prior myocardial infarction. We report a case of Takotsubo cardiomyopathy (TCM)secondary to GCT diagnosis in a young male. This patient presented withsymptoms of myocardial infarction however, coronary angiography was normal and a diagnosis of TCM was made. Though, it is rare but a unique challenge, as whether Cisplatin use would be safe in this particular scenario? On one hand patient had stress related myocardial injurywhile he was also at risk of further Cisplatin induced complications.There are no clear cut guidelines, so after informed consent his treatment regimen was modified to EC (Etoposide/Carboplatin) instead of EP (Etoposide/Cisplatin). Patient has completed 4.6 years of follow-up without any evidence of relapse. We suggest informed decisions and to weigh the pros and cons of using an inferior regimen, in order to achieve same long term prognosis while preventing any acute complications,in younger patients with curable cancers.
17

DMRT1-mediated reprogramming drives development of cancer resembling human germ cell tumors with features of totipotency / DMRT1を介した生体内での細胞初期化は全能性の特徴を持つヒト胚細胞腫瘍に類似したがんを形成する

Taguchi, Jumpei 24 January 2022 (has links)
京都大学 / 新制・課程博士 / 博士(医科学) / 甲第23611号 / 医科博第134号 / 新制||医科||9(附属図書館) / 京都大学大学院医学研究科医科学専攻 / (主査)教授 遊佐 宏介, 教授 小川 誠司, 教授 山中 伸弥 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM
18

The Germ Cell Fate of Cynomolgus Monkeys is Specified in the Nascent Amnion / カニクイザル生殖細胞は初期羊膜で形成される

Sasaki, Kotaro 23 May 2017 (has links)
京都大学 / 0048 / 新制・論文博士 / 博士(医学) / 乙第13112号 / 論医博第2130号 / 新制||医||1022(附属図書館) / (主査)教授 浅野 雅秀, 教授 瀬原 淳子, 教授 近藤 玄 / 学位規則第4条第2項該当 / Doctor of Medical Science / Kyoto University / DFAM
19

Paternal smoking as a cause for transgenerational damage in the offspring

Anderson, Diana, Schmid, Thomas E., Baumgartner, Adolf January 2015 (has links)
No / In 2013, the World Health Organization referred to tobacco smoking as an epidemic and a great threat to human health. Despite the obvious exposures from first- and secondhand smoking contributing to illnesses, an increased cancer risk, and death, there is a hidden risk to the next generation(s) from transgenerational mutations. In human populations, paternal preconceptional germ cell damage leading to genomic instability in offspring has always been difficult to evaluate as preconceptional and gestational exposures usually cannot be analyzed independently. Clear indications have been found that the effect of pre- and periconceptional paternal smoking may have been transmitted to the offspring via the spermatozoal genome and epigenome. Hence, cigarette smoke has to be considered a human germ cell mutagen due to its potential of inducing transgenerational DNA alterations in the unexposed F1 offspring of smoking-exposed fathers. For cohort studies, the practice of almost exclusively employing mother–childbirth pairs for the evaluation of lifestyle factors, such as smoking, while excluding the fathers’ contribution has to be reconsidered. Evidence now strongly points to the necessity of including the fathers in order not to miss paternal transgenerational damage in the offspring. This applies for genetic, epigenetic, and other transmissible effects.
20

The Role of Cell Death in Germ Cell Migration

RUNYAN, CHRISTOPHER MICHAEL 22 August 2008 (has links)
No description available.

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