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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.
341

Distribuição do IGF-I e do seu receptor na cartilagem do processo condilar da mandíbula e na sincondrose basiesfenoidal de ratos wistar subnutridos. / Distribution of IGF-I and its receptor in the cartilage of the mandibular condyle process and basiesphenoidal synchondrosis of the undernourished wistar rats.

Oliveira, Bruna Cecilia Caixeta de 22 November 2013 (has links)
A cartilagem do processo condilar (PC) e a sincondrose basiesfenoidal (SB) participam do processo de crescimento e desenvolvimento craniofacial que são determinados pelo aporte protéico, pela ação hormonal e por fatores de crescimento, sendo o IGF-I o principal deles. Objetivou-se correlacionar as alterações morfológicas no PC e na SB provenientes da subnutrição protéica. Os grupos experimentais foram formados por animais heterogêneos (n=5) com 60 dias de vida, de acordo com o teor de caseína contida nas rações, protéica (20%) ou hipoprotéica (5%), formando, respectivamente, os grupos nutrido (N) e subnutrido (S). Na microscopia de luz foi observado que a subnutrição não alterou as espessuras das camadas do PC e da SB, enquanto que através da imunohistoquímica o número de IGF-I e IGF-IR diminuiu em ambos os tecidos (N&ne;S; p<0,05). No PC, o colágeno do tipo I passou a ser do tipo II no grupo S, enquanto que na SB, o do tipo II foi destacado em ambos os grupos. A matriz extracelular do PC apresentou-se densa e com coloração homogênea nos nutridos, contrastando com o aspecto difuso dos subnutridos. Na SB, tanto no grupo N quanto no S, a MEC manteve-se com aspecto uniforme na distribuição e na homogeneidade da coloração. / The cartilage of the condylar process (CP) and the basiesfenoidal synchondrosis (BS) participate in the process of craniofacial growth and development that are determined by the protein content, the hormonal and growth factors, being the IGF-I main one. This study aimed to correlate the morphological changes in PC and SB from protein malnutrition. The experimental groups were formed by heterogeneous animals (n = 5) at 60 days of life, according to the casein contained in the feed, proteic (20%) or hypoproteic (5%), constituting respectively the nourished (N) and undernourished (U) groups. Under light microscopy it was observed that undernourished did not change the thickness of the layers of CP and BS by immunohistochemical while the number of IGFI and IGF-IR decreased in both tissues (N&ne;S; p<0,05). On the PC, the type I collagen became type II at the U group, while in the SB the type II was noted in both groups. The extracellular matrix (ECM) of the PC presented dense and homogenous coloration in the nourished, contrasting with the diffuse aspect of the undernourished. In SB, both in the N group as U, the ECM remained uniform in appearance and the distribution and uniformity of staining.
342

Studies of localization and expression of angiopoietin in the testis.

January 2001 (has links)
Wong Chun Yan. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2001. / Includes bibliographical references (leaves 149-160). / Abstracts in English and Chinese. / Abstract --- p.i / 摘要 --- p.iii / Abbreviations --- p.v / Acknowledgement --- p.x / Chapter Chapter 1 --- Introduction / Chapter 1.1 --- General review of angiogenesis --- p.1 / Chapter 1.1.1 --- Angiogenesis in development and growth --- p.1 / Chapter 1.1.2 --- The process of angiogenesis --- p.2 / Chapter 1.1.3 --- Types of factors controlling angiogenesis --- p.3 / Chapter 1.2 --- Roles of VEGF and its receptors in the regulation of angiogenesis --- p.6 / Chapter 1.2.1 --- VEGF --- p.6 / Chapter 1.2.2 --- VEGF receptors --- p.8 / Chapter 1.2.3 --- Regulation of VEGF expression by hypoxia and nitric oxide… --- p.10 / Chapter 1.2.4 --- Signal transduction mechanisms of VEGFR-1 and VEGFR-2 --- p.12 / Chapter 1.2.5 --- Anti-apoptotic effect ofVEGF on endothelial cells as a result of signal transduction of VEGFR-2 --- p.14 / Chapter 1.3 --- Angiopoietins --- p.15 / Chapter 1.3.1 --- Angiopoietin 1 (Ang-1) --- p.16 / Chapter 1.3.2 --- Angiopoietin 2 (Ang-2) --- p.19 / Chapter 1.3.3 --- Angiopoietins 3 and 4 (Ang-3 and Ang-4) --- p.24 / Chapter 1.4 --- "Interaction among VEGF, angiopoietin and Tie in the maintenance of vasculature" --- p.25 / Chapter 1.5 --- Tyrosine kinase with immunoglobulin and EGF factor homology domains - Tie 1 and Tie 2 --- p.28 / Chapter 1.6 --- Angiopoietin expression in female reproductive tissues (ovary) --- p.33 / Chapter 1.7 --- Testicular angiogenesis --- p.37 / Chapter 1.8 --- Aims of the present study --- p.38 / Chapter Chapter 2 --- Materials and methods / Chapter 2.1 --- Preparation of primary cells from rat testes --- p.40 / Chapter 2.1.1 --- Sertoli cell preparation --- p.40 / Chapter 2.1.2 --- Germ cell preparation --- p.41 / Chapter 2.1.3 --- Interstitial cell and Leydig cell preparation --- p.43 / Chapter 2.2 --- Cell cultures --- p.45 / Chapter 2.2.1 --- Reagents and cell lines --- p.45 / Chapter 2.2.2 --- Cell lines of mouse TM3 Leydig cells and TM4 Sertoli cells --- p.45 / Chapter 2.2.3 --- Mouse MLTC-1 Leydig tumour cells --- p.46 / Chapter 2.2.4 --- Rat R2C Leydig tumour cells --- p.46 / Chapter 2.2.5 --- Rat LC540 Leydig tumour cells --- p.47 / Chapter 2.2.6 --- "Rat C6 glioma cells.............," --- p.47 / Chapter 2.3 --- "Analyses of Angiopoietin 1, Angiopoietin 2, Angiopoietin3, Tie 1 receptor, and Tie 2 receptor mRNA in testicular cell lines and testicular tissues" --- p.48 / Chapter 2.3.1 --- Extraction of total RNA from testicular cell lines and testicular tissues --- p.48 / Chapter 2.3.2 --- Quantitation of total RNA --- p.50 / Chapter 2.3.3 --- First strand cDNA synthesis by reverse transcription (RT) --- p.51 / Chapter 2.3.4 --- Normalization of the amounts of cDNA usedin polymerase chain reaction (PCR) --- p.52 / Chapter 2.3.5 --- Polymerase chain reaction (PCR) --- p.53 / Chapter 2.3.6 --- Purification of PCR products --- p.65 / Chapter 2.3.7 --- Confirmation of PCR product authenticity by automated DNA sequencing --- p.66 / Chapter 2.4 --- Western blot analysis --- p.68 / Chapter 2.4.1 --- Preparation of cell lysates from primary testicular cells and testicular cell lines --- p.68 / Chapter 2.4.2 --- Preparation of mouse testicular tissue and adult rat testicular tissue lysates --- p.68 / Chapter 2.4.3 --- Determination of protein concentration --- p.69 / Chapter 2.4.4 --- Reagents for Western blot analysis --- p.70 / Chapter 2.4.5 --- Preparation of protein samples and markers for Western blot analysis --- p.71 / Chapter 2.4.6 --- Sodium dodecyl-sulphate polyacrylamide gel electrophoresis (SDS-PAGE) --- p.72 / Chapter 2.4.7 --- Transfer of proteins to membrane --- p.74 / Chapter 2.4.8 --- Blocking of the membrane --- p.74 / Chapter 2.4.9 --- Immunoblotting --- p.75 / Chapter 2.5 --- "Immunohistochemical staining for Ang-1, Ang-2,Ang-3, Tie 1 and Tie 2 in rat testes" --- p.78 / Chapter Chapter 3 --- Results / Chapter 3.1 --- Expression of Ang-1 and Ang-1 alternatively spliced transcripts in the testis and other testicular cell types --- p.81 / Chapter 3.1.1 --- Detection of Ang-1 expression in the testis and and testicular cell types by nested PCR --- p.81 / Chapter 3.1.2 --- Detection of Ang-1 expression in testicular cell lines by nested PCR --- p.82 / Chapter 3.1.3 --- Sequence analysis of Ang-1 transcript amplified from adult rat testis --- p.84 / Chapter 3.1.4 --- Detection of alternatively spliced species of Ang-1 mRNA in the testis and other testicular cell lines --- p.87 / Chapter 3.2 --- Expression of Ang-2 and Ang-2 isoforms in the testis and various testicular cell types --- p.94 / Chapter 3.2.1 --- Detection of Ang-2 expression in the testis and testicular cell types by nested PCR --- p.94 / Chapter 3.2.2 --- Detection of Ang-2 expression in testicular cell lines by nested PCR --- p.96 / Chapter 3.2.3 --- Sequence analysis of Ang-2 transcript amplified from adult rat testis --- p.98 / Chapter 3.2.4 --- Detection of the expression of Ang-2 isoforms in adult rat testis --- p.99 / Chapter 3.3 --- Expression of Ang-3 in the testis and testicular cell types --- p.103 / Chapter 3.3.1 --- Detection of Ang-3 expression in the testis and primary testicular cells by RT-PCR --- p.103 / Chapter 3.3.2 --- Detection of Ang-3 expression in testicular cell lines by RT-PCR --- p.105 / Chapter 3.3.3 --- Sequence analysis of Ang-3 transcripts amplified from TM4 mouse Sertoli cells and adult rat testis --- p.105 / Chapter 3.4 --- Expression of Tie 1 and Tie 2 in the testis and testicular blood vessel --- p.110 / Chapter 3.4.1 --- Detection of Tie 1 and Tie 2 expression in the testis and rat testicular blood vessel by RT-PCR --- p.110 / Chapter 3.4.2 --- Sequence analysis of Tie 1 transcripts amplified from adult rat testis and rat testicular blood vessel --- p.113 / Chapter 3.4.3 --- Sequence analysis of Tie 2 transcript amplified from rat testicular blood vessel --- p.113 / Chapter 3.5 --- "Western blot analysis of Ang-1 and Ang-2 expression in testicular tissues, primary testicular cells and cell lines" --- p.116 / Chapter 3.6 --- "Localization of Ang-1,Ang-2, Ang-4, Tie 1 and Tie2 proteins in adult rat testis by immunohistochemistry" --- p.122 / Chapter 3.7 --- "Comparison of angiopoietin expression patterns in testis using RT-PCR, Western immunoblotting and immunohistochemistry" --- p.128 / Chapter 3.8 --- Comparison of Tie 1 and Tie 2 expression patterns in testis using RT-PCR and immunohistochemistry --- p.128 / Chapter Chapter 4 --- Discussion / Chapter 4.1 --- "Expression of Ang-1 mRNA and protein in adult rat testis, mouse testis, rat testicular blood vessel, primary testicular cells and testicular cell lines" --- p.131 / Chapter 4.2 --- "Expression of Ang-2 mRNA and protein in adult rat testis, mouse testis, rat testicular blood vessel, primary testicular cells and testicular cell lines" --- p.136 / Chapter 4.3 --- "Expression of Ang-3 mRNA and protein in adult rat testis, mouse testis, rat testicular blood vessel, primary testicular cells and testicular cell lines" --- p.141 / Chapter 4.4 --- Expression of Tie 1 and Tie 2 mRNAs and proteinsin adult rat testis and rat testicular blood vessel --- p.143 / Chapter 4.5 --- Conclusion --- p.145 / Chapter 4.6 --- Future work --- p.146 / Chapter Chapter 5 --- References --- p.149
343

Attempts to clone the Limulus ependymin gene, and the effects of a human ependymin peptide on human SHSY neuroblastoma cells

Arca, Turkan 04 May 2005 (has links)
ABSTRACT This thesis was divided into two parts. The purpose of part I was to clone and sequence the full-length ependymin gene from the invertebrate Limulus polyphemus, or portions of the gene, and to use RT-PCR to determine whether expression of this gene increases during leg regeneration. PCR was chosen as the method for obtaining the gene due to the success our lab had previously characterizing several ependymin genes using this approach. Three sets of primers were designed based on the conserved domains between teleost fish and three invertebrate ependymin sequences. “Sea primers" were designed based on the nucleotide sequence of the sea cucumber H. glaberrima for each conserved domain, and these primers produced all four of the expected size amplicons with Limulus DNA, but surprisingly only one such band with the sea cucumber Sclerodactyla briareus. The consensus primers (con-primers) were designed based on the most conserved nucleotide among all known ependymin species at each particular position in the conserved domains. Primers designated“5-11 primers" were designed based on the absolutely conserved domains among the three known invertebrate ependymins. Neither con-primers nor 5-11 primers produced any bands of the expected size; this was true for both species of DNA. One very strong band was produced using“5-11" primer pair 6/10 with both species. One of the bands from this reaction from Limulus was cloned and sequenced, and showed a very strong homology (88% over 292 bp) with mouse FGF-14, a neurotrophic factor involved in mouse neurogenesis. The expression of this gene during leg regeneration will be tested in future experiments. Limulus GAPDH was also cloned and sequenced, and a genomic intron was identified for the first time in this study. This Limulus housekeeping gene will be used in future studies for gene expression comparisons. The purpose of part two of this thesis was to study the up-regulation of growth-related genes induced by treatment of a human neuroblastoma SH-SY5Y cell line with a human ependymin peptide mimetic (hEPN-1), in an attempt to help provide a basis for using human EPN mimetics as therapeutics in stroke and neurodegenerative diseases. The sequence of this mimetic is derived from an area of human MERP-1 analogous to goldfish mimetic CMX-8933. The human mimetic was previously found to up-regulate growth related genes L-19, EF-2 and ATP Synthase in the mouse neuroblastoma cell line Nb2a (Saif, 2004). The expression levels of genes encoding ribosomal proteins and ribosomal RNA were studied using RT-PCR as hallmarks of proliferating cells. hEPN-1 was found to increase the expression of the nuclear-encoded ribosomal proteins S-19 and S-12, an average of 2.76 fold and 1.74 fold, with statistically significant p-values of 0.031 and 0.015 (<0.05), respectively. The expression levels of nuclear-encoded 5.8S ribosomal RNA (p = 0.018) and the mitochondrial-encoded 16S RNA (p = 0.046) were found to be increased an average of 14.04 fold and 3.91 fold, respectively. Thus, human ependymin mimetic hEPN-1 appears to stimulate growth-related genes, a property which can be useful to regenerate neuronal tissue after injury.
344

Fungos nematófagos em diferentes solos e caracterização filosófica de Arthrobotrys oligospora /

Cardoso, Eliane Ribeiro. January 2007 (has links)
Orientador: Ely Nahas / Banca: João Lúcio de Azevedo / Banca: Drauzio Eduardo Naretto Rangel / Banca: jaime Mais dos Santos / Banca: Rita de Cássia panizzi / Resumo: O uso de agentes biológicos para controle de nematóides é considerado uma das várias medidas a serem empregadas em um manejo integrado de pragas, sendo uma preocupação de caráter mundial. Contudo, foram estudados os fatores determinantes da freqüência de fungos totais e nematófagos, da atividade enzimática e da distribuição de nematóides de solos não rizosféricos e rizosféricos sob alface (Lactuca sativa L.); banana (Musa cavendishii L.); grama batatais (Paspalum notatum) e Impatiens (Impatiens valleriana). A atividade predadora dos fungos nematófagos foi avaliada contra o nematóide Panagrellus redivivus. O número de fungos totais variou de 6,9 x 105 a 31,2 x 105 UFC g-1 solo seco no solo não-rizosférico e de 6,9 x 105 a 25,6 x 105 UFC g-1 solo seco no solo rizosférico. As contagens dos fungos nematófagos corresponderam a 23-41 % e 23-34 % dos fungos totais encontrados no solo rizosférico e não-rizosférico, respectivamente. Enquanto as contagens dos fungos totais do solo rizosférico se distribuíram na seguinte seqüência: alface > banana > grama-batatais > Impatiens, os nematófagos diminuíram na seguinte ordem: alface > Impatiens > banana > grama-batatais. A matéria orgânica e a umidade do solo influenciaram a distribuição tanto dos fungos totais como dos nematófagos do solo não-rizosférico. A distribuição dos nematóides nas amostras de solo e raiz foram Rotylenchulus sp., Helicotylenchus sp. e Tylenchus sp. para alface, Meloidogyne sp., Helicotylenchus sp., Pratylenchus sp. e Rotylenchulus sp. para banana, Meloidogyne sp., Helicotylenchus sp., Pratylenchus sp. e Rotylenchulus sp. para grama-batatais, Meloidogyne sp., Helicotylenchus sp., Pratylenchus sp., Rotylenchulus sp. e Tylenchus sp. para Impatiens. Em termos gerais, as atividades da desidrogenases, amilases, celulases e endoglucanases distribuíram-se no solo não-rizosférico de acordo ...(Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Biological control of nematodes is considered one of the many practices that can be used in integrated pest management. We investigated the factors affecting the frequency of the total and the nematophagous fungi, soil enzymatic activity as well as the distribution of the nematodes in rhizospheric and bulk soil of lettuce (Lactuca sativa L.); Impatiens (Impatiens valleriana); banana (Musa cavendishii L.) and Bahiagrass (Paspalum otatum). The effect of the nematophagous fungi were evaluated against the nematode Panagrellus redivivus. The total fungal number ranged from 6,9 x 105 to 31,2 x 105 UFC g-1 dry soil in the bulk soil and from 6,9 x 105 to 25,6 x 105 UFC g-1 dry soil in the rhizosphere. Nematofagous fungi counts were to 23-41 % and 23-34 % of the total fungi found in the rhizosphere and bulk soil, respectively. While the total fungi counts of the rizosphere were distributed in the following sequence: lettuce > banana > Bahiagrass > Impatiens, the nematophagous fungi decreased in the following order: lettuce> Impatiens >banana > Bahiagrass. Moisture and organic matter contents of the bulk soil influenced the distribution of the total and nematophagous fungi of the soil. The following phytonematodes found in the samples of soil and roots were Rotylenchulus sp., Helicotylenchus sp. and Tylenchus sp (lettuce), Meloidogyne sp., Helicotylenchus sp., Pratylenchus sp. and Rotylenchulus sp (banana), Meloidogyne sp., Helicotylenchus sp., Pratylenchus sp. and Rotylenchulus sp. (Bahiagrass), Meloidogyne sp., Helicotylenchus sp., Pratylenchus sp., Rotylenchulus sp. and Tylenchus sp. (Impatiens). In general, the activities of the enzymes desidrogenase, amylase, celulase and endoglucanase followed the distribution of the frequency of the soil total and nematophagous fungi ...(Complete abstract, click electronic access below) / Doutor
345

Mutant p53 cooperates with the SWI/SNF chromatin remodeling complex to mediate VEGFR2 expression in breast cancer cells

Pfister, Neil Thomas January 2015 (has links)
Mutant p53 impacts the expression of numerous genes at the level of transcription to mediate oncogenesis. To investigate how mutant p53 impacts transcription, we studied how mutant p53 regulates vascular endothelial growth factor receptor 2 (VEGFR2), one of its strongest target genes that we identified through global gene expression profiling in mutant p53 expressing MDA 468 breast cancer cells. VEGFR2, the primary functional VEGF receptor and clinical target of bevacizumab, mediates endothelial cell neovascularization by promoting increased cellular proliferation, migration, and pro-survival signaling. In breast tumors, VEGFR2 is often aberrantly expressed on the breast tumor epithelia,which correlates with worse overall survival. We identify VEGFR2 as a mutant p53 transcriptional target in multiple breast cancer cell lines. Mutant p53 mediated upregulation of VEGFR2 mediates mutant 53 gain of function including increased cellular growth and migration. In humans, breast tumors with TP53 hotspot mutants have elevated VEGFR2 levels compared to tumors with loss of function mutations. The same class of tumors has significantly upregulated HIF1A and VEGFA compared to TP53 wild type tumors, indicating that mutant p53 containing breast tumors express a neoangiogenic gene signature that may intensify VEGFR2 autocrine signaling. A clinical trial suggests that TP53 mutated breast tumors may specifically respond to anti VEGF therapy, while TP53 wild type tumors may not respond. We suggest that mutant p53 containing breast tumors may be distinctively vulnerable to anti VEGF ntherapies. We investigated how mutant p53 impacts transcription of VEGFR2 using multiple techniques including scanning ChIP, micrococcal nuclease PCR, and in vivo DNase I footprinting by ligation mediated PCR. Mutant p53 was found to bind near the VEGFR2 transcriptional start site, causing the promoter to adopt a transcriptionally active conformation. Using SILAC mass spectrometry, we identified subunits of the SWI/SNF chromatin remodeling complex as mutant p53 interactors. Importantly, re ChIP and immunodepletion ChIP demonstrate that mutant p53 and SWI/SNF co-occupy the VEGFR2 promoter. Depletion of multiple SWI/SNF subunits reduced VEGFR2 RNA expression, and SWI/SNF is required for maximal mutant p53 promoter occupancy. Using RNA sequencing, we report that approximately half of all mutant p53 gene alteration impacts transcription of VEGFR2 as well as myriad other target genes by promoter remodeling through interaction with the SWI/SNF chromatin remodeling complex. Therefore, not only might mutant p53 expressing tumors be uniquely susceptible to anti VEGF therapies, but restoration of SWI/SNF tumor suppressor function by targeting mutant p53 may have therapeutic potential. Mutant p53 interaction with the SWI/SNF complex may explain how mutant p53 modulates the expression of such a diverse set of genes.
346

Expressão do mRNA do VEGF, FIt-1 e KDR no placentoma, região interplacentomal e corpo lúteo em diferentes fases gestacionais em bovinos clonados e não clonados / Expression of mRNA of the VEGF, Flt-1 and KDR in placentome, interplacentomal areas and gestational corpus luteum in different phases of pregnancy in cloned and non-cloned bovines

Garbelotti, Fernando 31 May 2006 (has links)
O VEGF é um fator mitogênico específico de células endoteliais que promove diferenciação celular materno-fetal placentária quando ligado a seus receptores (Flt-1 e KDR). Sua expressão é controlada por mecanismos autócrinos e parácrinos e está associada ao desenvolvimento da placenta. A placenta bovina foi utilizada como modelo de estudo por apresentar a facilidade de se avaliar os componentes do sistema VEGF em diferentes fases gestacionais. Como objetivo este estudo buscou analisar o fator de crescimento vascular endotelial (VEGF) e seus receptores através da técnica de PCR em tempo real no início, meio e fim de gestação. Para tanto, amostras de placentomas, região interplacentomal e corpo lúteo foram coletadas em diferentes fases gestacionais. Foram utilizados placentomas de animais clonados obtidos apenas aos 270 dias de gestação e estas amostras foram comparadas aos animais não clonados na mesma fase. A expressão do VEGF no placentoma apresentou um decréscimo (p &lt; 0.05) no final da gestação (270 dias) em relação à expressão do VEGF aos 90 dias. A expressão do Flt-1 e do KDR na região interplacentomal foi semelhante desde os 45 até 90 dias de gestação e apresentou um aumento significativo (p &lt; 0.05) aos 150 dias. No corpo lúteo gestacional, a expressão do VEGF aos 210 dias foi maior (p &le; 0.05) em relação a 90 e 150 dias; observou-se também baixa expressão do KDR aos 90 dias de gestação (p &lt; 0.05) em relação aos 210 dias. Pode-se concluir que a regulação da expressão do VEGF variou em relação aos seus receptores nos três tecidos avaliados. Placentomas de bovinos clonados não apresentaram diferenças significativas em relação à expressão do sistema VEGF se comparados aos placentomas de animais não clonados sugerindo ser esta expressão equivalente em placentas de animais clonados que vieram a termo. / The VEGF is a specific endothelial mitogenic factor that promotes feto-maternal cell differentiation in placenta through binding to its receptors (Flt-1 and KDR). Their expression is controlled by autocrine and paracrine mechanisms that are associated to placenta development. The bovine placenta was used in this study as a model due to easiness of evaluation of VEGF system components in different phases of pregnancy. The objective of this study was to analyze the vascular endothelial growth factor (VEGF) and its receptors expression using the real time PCR technique in the beginning, half and end of pregnancy. Furthermore, placentome samples, interplacentomal areas and corpus luteum were collected in different gestational phases for comparative studies. Placentome of cloned animals were analyzed at 270 days of pregnancy and compared to non-cloned animals in the same phase. The expression of VEGF in the placentome presented a decrease of expression (p &lt; 0.05) in the end of the gestation (270 days) in relation to 90 days. The expression of Flt-1 and of KDR in interplacentomal area was similar from 45 to 90 days of pregnancy with a significant increase (p &lt;0.05) observed at 150 days. In the gestational corpus luteum, the expression of VEGF at 210 days was higher (p &le; 0.05) in comparison to 90 and 150 days. In the same tissue KDR expression at 90 days was lower (p &lt; 0.05) in relation to 210 days. In conclusion the regulation VEGF varied in relation to its receptors expression in all three studied tissues. Cloned placentomes showed no significant differences in VEGF system expression compared to the placentome of non-cloned animals, suggesting there is an equivalent expression in placentas from cloned animals that came to term.
347

Imunolocalização do VEGF, bFGF e seus receptores na placenta bovina e influência destes fatores sobre a produção de progesterona pelas células placentárias em cultura / Immunolocalization of VEGF, bFGF and their receptors in the bovine placenta and influence of these growth factors on progesterone production from placental cells in culture

Campos, Danila Barreiro 06 July 2005 (has links)
O estabelecimento e perfeito funcionamento da placenta são fatores dependentes da intensa vascularização ocorrida no órgão. Os processos de vasculogênese e angiogênese placentária são modulados por diversos fatores, incluindo o VEGF (fator de crescimento vascular endotelial) e bFGF (fator de crescimento fibroblástico básico). Apesar da importância do VEGF e bFGF durante a vascularização estar estabelecida, vários estudos indicam a participação desses fatores de crescimento como moduladores locais em outras funções fisiológicas, como por exemplo o controle da produção hormonal em tecidos esteroidogênicos. Animais clonados podem apresentar alterações na expressão de determinados genes durante seu desenvolvimento, o que pode alterar a função placentária. Os objetivos deste estudo são determinar a localização tecidual do VEGF, bFGF e seus receptores na placenta bovina e avaliar a influência destes fatores de crescimento sobre a produção de progesterona placentária em bovinos não clonados e clonados. Placentomas de 90, 150 e 210 dias de gestação foram obtidos em abatedouro e placentônios de gestações aos 270 dias provenientes de bovinos clonados e não clonados foram coletados após cesarianas. As amostras foram fixadas em formol tamponado 4%, desidratadas e incluídas em parafina. Cortes foram submetidos a imuno-histoquímica para posterior localização das proteínas do VEGF, bFGF e seus receptores. Sob condições assépticas, as células foram mecanicamente dispersas e cultivadas em placas de 96 cavidades. Os fatores foram adicionados em concentrações de 10 e 50 &#951;g/ml de bFGF e VEGF, respectivamente. Amostras de meio de cultura e as células dos grupos controle, bFGF, VEGF e VEGF mais bFGF foram coletadas 24, 48 e 96 horas após a adição dos fatores. A progesterona foi dosada por radioimunoensaio e o conteúdo protéico pelo método de Lowry. Os dados foram analisados utilizando-se o programa estatístico SAS (Statistical Analysis System), as diferenças estatísticas encontradas foram comparadas pelo teste de variação múltipla de Duncan. O VEGF, bFGF e seus receptores foram localizados em células do epitélio e estroma maternos e fetais e células endoteliais vasculares em bovinos não clonados e clonados. As células placentárias apresentaram diferentes capacidades de síntese de progesterona ao longo da gestação. Aos 90 e 210 dias de gestação o VEGF estimulou a produção de progesterona, enquanto aos 270 dias de gestação o fator inibiu a produção deste hormônio. O bFGF estimulou a produção de progesterona pelas células placentárias aos 90 dias de gestação. A adição dos dois fatores de crescimento conjuntamente determinou um estímulo na produção de progesterona aos 210 dias de gestação. A produção de progesterona pelas células de bovinos clonados foi semelhante àquela observada em células de bovinos não clonados na mesma idade gestacional e os fatores de crescimento não influenciaram essa produção. Conclui-se que o VEGF e bFGF, atuando localmente no tecido placentário, funcionam como moduladores do processo de esteroidogênese, influenciando de maneira tempo-dependente a produção de progesterona deste órgão. / Placental establishment and function are dependent on intense vascularization. Placental vasculogenesis and angiogenesis are modulated by several factors, including VEGF (vascular endothelial growth factor) and bFGF (basic fibroblast growth factor). Although the role of VEGF and bFGF during vascularization is already well established, some studies have indicated the participation of these growth factors as local modulators in other physiological functions, such as control of hormonal production in steroidogenic tissues. Cloned animals may exhibit alterations in gene expression during development modifying placental function. The aims of this study are to determine the tissue localization of VEGF, bFGF and their receptors in the bovine placenta and to evaluate the influence of bFGF and VEGF on placental progesterone production in non-cloned and cloned bovines. Placentomes from days 90, 150 and 210 of pregnancy were obtained at local slaughterhouse and placentomes from cloned and non-cloned gestations at 270 days were obtained after cesarean sections. Samples were fixed in 4% buffered formol solution, dehydrated and included in paraffin. Sections were subimitted to immunohistochemistry for subsequent localization of VEGF, bFGF and their receptors proteins. Under aseptic conditions, cells were mechanically dispersed and then cultivated in a 96-well plate. Growth factors were added at concentrations of 10 and 50 &#951;g/ml for bFGF and VEGF, respectively. Samples of culture medium and cells from control, bFGF, VEGF and bFGF plus VEGF groups were collected 24, 48 and 96 hours after growth factor addition. Progesterone concentrations were assessed by radioimmunoassay and protein content was measured by Lowry?s method. Data were analyzed by SAS (Statistical Analysis System) program, significant differences were compared by Duncan?s range multiple test. VEGF, bFGF and their receptors were localized in maternal and fetal epithelial and stromal cells and vascular endothelial cells during pregnancy in non-cloned animals and in cloned bovine placenta at 270 days of pregnancy. Bovine placental cells were able to produce different amounts of progesterone during pregnancy. Growth factors were able to influence progesterone production in placental cells only after 24 hours in culture. At 90 and 210 days of pregnancy VEGF stimulated progesterone production, while at 270 days of pregnancy the growth factor inhibited production of this hormone. bFGF stimulated progesterone production in placental cells from 90 days of pregnancy. Both growth factors together determined an increase in progesterone production in placental cells from 210 days of pregnancy. Progesterone production in placental cells from cloned cattle is similar when compared with non-cloned placental cells at the same gestational age and growth factors did not influence progesterone production in these cells. VEGF and bFGF, acting locally in the placental tissue, are modulators of the steroidogenic process, influencing in a time-dependent manner the progesterone production in this organ.
348

The trophic properties of glial cells under glucose deficiency.

January 2005 (has links)
Lai, Ching Janice. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2005. / Includes bibliographical references (leaves 148-168). / Abstracts in English and Chinese. / Abstract --- p.i / Abstract in Chinese --- p.iii / Acknowledgements --- p.v / Table of Content --- p.vi / List of Tables --- p.x / List of Figures --- p.xi / Abbreviations --- p.xii / Chapter Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- General Introduction --- p.1 / Chapter 1.2 --- Nervous System and the Blood-Brain-Barrier --- p.3 / Chapter 1.3 --- Glial cells --- p.3 / Chapter 1.4 --- Studying Astrocyte Responses As a New Direction in Neuroscience --- p.4 / Chapter 1.5 --- The Roles of Astrocyte in the CNS --- p.5 / Chapter 1.5.1 --- Energy-Dependent Communication Between Neurons and Astrocytes --- p.7 / Chapter 1.5.2 --- Strategies for Metabolic Exchange Between Astrocytes and Neurons --- p.8 / Chapter 1.5.2.1 --- Provision of Energy Metabolites to Neurons by Astrocytes --- p.9 / Chapter 1.5.2.2 --- Glucose Transporters in the CNS --- p.10 / Chapter 1.5.2.3 --- The Lactate Shuttle Hypothesis --- p.12 / Chapter 1.5.2.4 --- The Regulation of Glucose Uptake at the Blood-Brain-Barrier (BBB) by the Activity of Neurons --- p.14 / Chapter 1.5.3 --- Alternation of Energy Metabolism in Neuropathy --- p.15 / Chapter 1.5.3.1 --- Ketone Body Shuttle Hypothesis --- p.15 / Chapter 1.5.3.2 --- The Utilization of Free Fatty Acids by the Brain --- p.17 / Chapter 1.5.4 --- The Provision of Neurotrophic Factors to Neurons by Astrocytes --- p.17 / Chapter 1.5.4.1 --- Neurotrophins --- p.18 / Chapter 1.5.4.1.1 --- Relationship Between Neurotrophins and Glucose --- p.20 / Chapter 1.5.4.2 --- S100B --- p.21 / Chapter 1.5.5 --- Astrocytic Cholesterol in Astrocytes as a Neurotrophic Factor --- p.22 / Chapter 1.6 --- Neuroprotective Effect of Glucose vi - --- p.23 / Chapter 1.7 --- Diseases Associated with Decreased Glucose Transport at the BBB --- p.24 / Chapter 1.7.1 --- Glucose Transporter Type 1 Deficiency Syndrome (GlutlDS) --- p.24 / Chapter 1.7.2 --- Hypoglycemia with Insulin Therapy for Diabetes Patients --- p.24 / Chapter 1.8 --- Aims and Hypothesis of Study --- p.26 / Chapter Chapter 2. --- 2 Materials and Methods --- p.27 / Chapter 2.1 --- Materials --- p.27 / Chapter 2.1.1 --- Cell Culture --- p.27 / Chapter 2.1.1.1 --- Cells --- p.27 / Chapter 2.1.1.1.1 --- C6 cells --- p.27 / Chapter 2.1.1.1.2 --- Primary Astrocytes --- p.27 / Chapter 2.1.1.2 --- Cell Culture Reagent --- p.27 / Chapter 2.1.2 --- Study of Growth Properties --- p.31 / Chapter 2.1.2.1 --- Equipment for Growth Curve Construction --- p.31 / Chapter 2.1.2.2 --- Reagents for Flow Cytometry --- p.32 / Chapter 2.1.2.3 --- Reagents for 3H-thymidine Incorporation Assay --- p.32 / Chapter 2.1.3 --- Study of Neurotrophic Properties --- p.33 / Chapter 2.1.3.1 --- Determination of Neurotrophic Factor Productions --- p.33 / Chapter 2.1.3.1.1 --- Reagents and Buffers for Northern Blot Analysis --- p.33 / Chapter 2.1.3.2 --- Reagents and Buffers for Western Blot Analysis --- p.43 / Chapter 2.1.3.2.1 --- Protein Assay --- p.43 / Chapter 2.1.3.2.2 --- Reagents for SDS Polyacrylamide Electrophoresis of Proteins --- p.44 / Chapter 2.1.3.2.3 --- Reagents for the Transfer of Protein to Membrane and Signal Detection --- p.47 / Chapter 2.1.4 --- Study of Lipid in Glial cells --- p.50 / Chapter 2.1.4.1 --- Determination of Genes Expression in Lipid Metabolism --- p.50 / Chapter 2.1.4.2 --- Reagents for Determination of Cholesterol and Fatty Acid Levels by Gas Chromatography --- p.50 / Chapter 2.2 --- Methods --- p.54 / Chapter 2.2.1 --- Cell culture --- p.54 / Chapter 2.2.1.1 --- Maintenance of C6 cells --- p.54 / Chapter 2.2.1.2 --- Primary Culture of Rat Astrocytes --- p.54 / Chapter 2.2.2 --- Study of Growth Properties of Glial Cells vii - --- p.56 / Chapter 2.2.2.1 --- Construction of cell growth curve --- p.56 / Chapter 2.2.2.2 --- Flow Cytometric Analysis of Cell Cycle Profile --- p.56 / Chapter 2.2.2.3 --- Measurement of DNA Synthesis --- p.57 / Chapter 2.2.3 --- Study of Neurotrophic Properties --- p.58 / Chapter 2.2.3.1 --- Determination of Neurotrophic Facotor Production --- p.58 / Chapter 2.2.3.1.1 --- Northern Blot Analysis --- p.58 / Chapter 2.2.3.1.2 --- Western Blot Analysis --- p.67 / Chapter 2.2.3.2 --- Determination of Gene Expression in Lipid Metabolism --- p.72 / Chapter 2.2.3.2.1 --- Northern Blot Analysis --- p.72 / Chapter 2.2.3.2.2 --- RT-PCR --- p.72 / Chapter 2.2.3.3 --- Study of Lipid Profiles in Glial Cells --- p.73 / Chapter 2.2.3.3.1 --- Sample preparation --- p.73 / Chapter 2.2.3.3.2 --- Total Cholesterol Determination --- p.73 / Chapter 2.2.3.3.3 --- Total Fatty Acid Determination --- p.75 / Chapter 2.2.3.3.4 --- Quantification of Proteins --- p.76 / Chapter 2.2.4 --- Statistical Analysis --- p.77 / Chapter Chapter 3 --- Results --- p.78 / Chapter 3.1 --- The effects of glucose deficiency on cell proliferation --- p.78 / Chapter 3.1.1 --- Direct Cell Count Assay --- p.78 / Chapter 3.1.2 --- Flow Cytometry Assay --- p.83 / Chapter 3.1.3 --- 3H-Thymidine Uptake Assay --- p.85 / Chapter 3.2 --- The Effects of Glucose Deficiency on Neurotrophic Properties of Glial Cells --- p.87 / Chapter 3.2.1 --- The Effects of Glucose Deficiency on mRNA and Protein Expressions of Neurotrophins --- p.88 / Chapter 3.2.1.1 --- Northern Blot Assays --- p.88 / Chapter 3.2.1.2 --- Western Blot Assays --- p.93 / Chapter 3.2.2 --- The Effects of Glucose Deficiency on Lipid Homeostasis --- p.96 / Chapter 3.2.2.1 --- Northern Blot Assays --- p.96 / Chapter 3.2.2.2 --- Gas Chromatography Assays --- p.101 / Chapter 3.2.2.2.1 --- Cholesterol Analyses --- p.102 / Chapter 3.2.2.2.2 --- Fatty Acid Analyses --- p.105 / Chapter Chapter 4 --- Discussion --- p.115 / Chapter 4.1 --- The in vitro Model of Hypoglycorrhachia --- p.115 / Chapter 4.2 --- Decreased Glucose Level Triggers Changes of Gial Cells Proliferation --- p.117 / Chapter 4.3 --- Expression of Neurotrophic Factor under Glucose Deficiency viii - --- p.120 / Chapter 4.3.1 --- Alteration of the Expression of Neurotrophins --- p.120 / Chapter 4.3.1.1 --- NGF --- p.122 / Chapter 4.3.1.2 --- BDNF --- p.123 / Chapter 4.3.1.3 --- NT-3 --- p.126 / Chapter 4.3.1.4 --- NT-4/5 --- p.128 / Chapter 4.3.2 --- Alteration of the mRNA Expression of Calcium Binding ProteinS100B --- p.128 / Chapter 4.4 --- Alteration of Lipid Metabolism in Decreased Glucose Supply --- p.130 / Chapter 4.4.1 --- Up-regulation of ApoE mRNA Expression in Glucose Deficiency --- p.133 / Chapter 4.4.2 --- Cholesterol Homeostasis in Glial Cells --- p.133 / Chapter 4.4.3 --- Fatty Acids Homeostasis in Glial Cells --- p.135 / Chapter 4.4.4 --- Decreased Ketone Bodies synthesis in Glucose Deficiency --- p.143 / Chapter 4.5 --- Limitations of the Current Study --- p.144 / Chapter 4.6 --- Future Directions --- p.145 / Chapter Chapter 5 --- Conclusion --- p.147 / References --- p.148 / Appendix --- p.169
349

The role of TGF-β/Smad signaling in diabetic nephropathy. / 生長轉化因子TGF-β/Smad信號通路在糖尿病腎病中的作用 / Role of TGF-beta/Smad signaling in diabetic nephropathy / CUHK electronic theses & dissertations collection / Sheng zhang zhuan hua yin zi TGF-β/Smad xin hao tong lu zai tang niao bing shen bing zhong de zuo yong

January 2012 (has links)
研究介紹:炎症與纖維化是糖尿病腎病(DN)的主要特徵。研究發現生長轉化因子TGF-β/Smad信號在糖尿病所致炎症與纖維化中均起重要作用。我們認為TGF-β/Smad信號通路失調是導致糖尿病腎損傷的主要機制,恢復信號通路或有治療價值。為此我們通過以下研究證實:(1)研究Smad7基因在DN中的作用,及評估Smad7基因治療效果;(2)研究miR-29在DN中的作用,及評估miR-29基因治療效果;(3)研究C反應蛋白(CRP)在DN中的作用及機制。 / 研究方法:(1)利用Smad7基因敲除(KO)小鼠建立糖尿病小鼠,並研究Smad7基因在DN的作用,並在链脲佐菌素(STZ)誘導的糖尿病大鼠上利用微泡導入Smad7基因治療觀察其療效;(2)在10週齡db/db小鼠上利用微泡導入可誘導的miR-29b基因,觀察miR-29b在糖尿病腎病中的作用,並用miR-29敲除或高表達細胞株研究其機制;(3)利用CRP轉基因小鼠誘導糖尿病,觀察CRP在DN中的作用,及以高糖和/或CRP刺激腎小管細胞研究CRP的致病機制。 / 研究結果:我們發現(1)糖尿病Smad7 KO小鼠出現更嚴重的腎損傷,包括蛋白尿增加,腎臟炎症及纖維化加重。進一步研究發現Smad7下調所致TGF-β/Smad和NF-kB信號過度活化是導致腎臟炎症及纖維化加重的重要原因。運用基因治療恢復糖尿病大鼠的Smad7水平,發現能夠減輕蛋白尿增加,及抑制TGF-β/Smad引起的纖維化和NF-kB所致炎症反應;(2)我們發現miR-29b在20週齡db/db小鼠比10週齡的顯著降低,並伴隨有蛋白尿加重,腎臟纖維化和炎症反應增加,及TGF-β/Smad,NF-kB,T-bet信號上調,而miR-29b基因治療能減輕蛋白尿,及減輕腎臟纖維化和炎症反應增加,及TGF-β/Smad,NF-kB,T-bet信號上調。體外實驗證實AGEs刺激miR-29敲除細胞株增加纖維化,伴隨有TGF-β/Smad3及炎症因子上調,而刺激高表達細胞株能抑制纖維化,及TGF-β/Smad和炎症因子下調;(3)糖尿病CRP轉基因小鼠出現更嚴重的腎損傷,出現蛋白尿和腎損傷分子-1上升、巨噬細胞和T細胞侵潤、炎症和纖維化增加,並伴有CRP受體(CD32a)上調、TGF-β/Smads及NFκB/p65信號過度活化。體外實驗進一步證實CRP通過其受體CD32a/CD64增加炎症和纖維化。另外證實CRP與高糖有協同作用。 / 結論:TGF-β/Smad信號通路是糖尿病腎病的重要致病機制。糖尿病腎病導致Smad7、miR-29b下調,運用基因治療恢復其表達能減輕糖尿病腎損傷。 / Diabetic nephropathy (DN) is characterized by renal fibrosis and inflammation. Increasing evidence shows that TGF-β/Smad signaling plays a critical role in DN. This thesis tested a hypothesis that TGF-β/Smad signaling may play a central role in diabetic kidney injury and targeting this pathway may represent a novel therapy for DN. The hypothesis was tested in a type-1 model of diabetes induced in Smad7 knockout (KO) or CRP transgene, and the therapeutic potential for DN was examined by overexpressing renal Smad7 or miR-29b in both type-1 or type-2 models of diabetes. / As described in Chapter Three, the protective role and therapeutic potential of Smad7 in diabetic kidney disease was investigated in streptozotocin-induced diabetic model in Smad7 KO mice and in diabetic rats given Smad7 gene transfer using an ultrasound-microbubble-mediated technique. Results showed that Smad7 KO mice developed more severe diabetic kidney injury than wild type (WT) mice as evidenced by a signicant increase in microalbuminuria, renal brosis, and renal inammation, which was mediated by enhanced activation of both TGF-β/Smads and NF-κB signaling pathways. To develop a therapeutic potential for diabetic kidney disease, Smad7 gene was transferred into the kidney, which results in high levels renal Smad7, thereby blocking microalbuminuria, TGF-β/Smad3-mediated renal brosis and NF-κB/p65-driven renal inammation in diabetic rats. / To test a novel hypothesis that TGF-β/Smad3-mediated DN via the Smad3-dependent miR-29, in Chapter Four, the role and mechanisms of miR-29b in DN were examined in vitro in a stable mesangial cell line with overexpression or knockdown of miR-29b and the therapeutic effect of miR-29b on DN was developed by delivering a Dox-inducible miR-29b into 10-week db/db mice. Results showed that addition of AGEs induced a loss of miR-29b with increased fibrosis and inflammation in mesangial cells, which was further enhanced with miR-29b knockdown, but inhibited by overexpressing miR-29b. In db/db mice, reduction of renal miR-29b over the 20 week time was associated with a marked increase in microabluminuria, renal fibrosis and inflammation. Restoring miR-29b resulted in inhibition of kidney injuries by blocking TGF-β/Smad3-mediated renal fibrosis, NF-kB/p65-driven renal inflammation, and importantly, the Th1-dependent immune response, revealing a critical role and therapeutic potential for miR-29b in the pathogenesis of DN. / Finally, diabetic kidney injury was also assessed in under high inflammation conditions in CRP transgenic (Tg) mice. As shown in Chapter Five, CRP Tg mice developed more severe diabetic kidney injury than WT mice, as evidenced by a significant increase in microalbuminuria and kidney injury molecule-1, macrophages and T cells, and upregulation of pro-inflammatory cytokines and extracellular matrix. CRP-mediated DN was associated with upregulation of CRP receptor, CD32a, and over-activation of the TGF-β/Smads and NFκB/p65 signaling pathways. These findings were further confirmed in vitro under high levels of CRP. In addition, CRP was induced by high glucose, which synergistically promoted high glucose-mediated renal inflammation and fibrosis, suggesting a positive feedback-loop between CRP and high glucose under diabetic conditions. / In conclusion, TGF-β/Smads play critical roles in the pathogenesis of DN. Loss of renal Smad7 and miR-29b may be a key mechanism of DN. Thus, over-expression of Smad7 or miR-29b may represent novel therapeutic strategies for diabetic kidney complications. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Chen, Haiyong. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2012. / Includes bibliographical references (leaves 202-236). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese. / ABSTRACT --- p.ii / DECLARATION --- p.vi / ACKNOWLEDGEMENT --- p.vii / PUBLICATIONS --- p.ix / PRESENTATIONS/AWARDS --- p.xi / TABLE OF CONTENTS --- p.xii / LIST OF ABBREVIATIONS --- p.xxii / LIST OF FIGURES/TABLES --- p.xxiv / Chapter CHAPTER ONE --- INTRODUCTION --- p.1 / Chapter 1.1 --- TGF-β superfamily --- p.2 / Chapter 1.2 --- TGF-β/Smad signaling pathway --- p.3 / Chapter 1.2.1 --- TGF-β --- p.3 / Chapter 1.2.1.1 --- TGF-β structure --- p.3 / Chapter 1.2.1.2 --- Activation of latent TGF-β --- p.4 / Chapter 1.2.1.3 --- Latent TGF-β receptors --- p.6 / Chapter 1.2.2 --- TGF-β signaling pathway --- p.7 / Chapter 1.2.2.1 --- Receptors --- p.7 / Chapter 1.2.2.2 --- Smads --- p.10 / Chapter 1.2.2.3 --- Smad-dependent TGF-β signaling pathways --- p.13 / Chapter 1.2.2.4 --- Smad-independent TGF-β signaling pathways --- p.14 / Chapter 1.3 --- Diabetes nephropathy --- p.15 / Chapter 1.3.1 --- Diabetes Mellitus --- p.15 / Chapter 1.3.2 --- Type 1 and type 2 diabetes --- p.16 / Chapter 1.3.3 --- Diabetic complications --- p.16 / Chapter 1.3.4 --- Cellular and molecular mechanisms in diabetic complications --- p.17 / Chapter 1.3.4.1 --- Increased polyol pathway flux --- p.17 / Chapter 1.3.4.2 --- Increased advanced glycation end-products (AGEs) formation --- p.18 / Chapter 1.3.4.3 --- Activation of protein kinase C (PKC) isoforms --- p.20 / Chapter 1.3.4.4 --- Increased hexosamine pathway flux --- p.22 / Chapter 1.3.4.5 --- Increased Reactive Oxygen Species --- p.23 / Chapter 1.3.5 --- Diabetic kidney injuries --- p.24 / Chapter 1.3.5.1 --- Exacerbation of renal structure and function --- p.24 / Chapter 1.3.5.2 --- Fibrosis in diabetic nephropathy --- p.25 / Chapter 1.3.5.3 --- Inflammation in diabetic nephropathy --- p.26 / Chapter 1.4 --- Role of TGF-β/Smad signaling pathway in diabetic nephropathy --- p.28 / Chapter 1.4.1 --- Smad-depedent signaling in diabetic nephropathy --- p.28 / Chapter 1.4.2 --- Cross talk between Smads and other signaling pathways in diabetic nephropathy --- p.30 / Chapter 1.4.3 --- TGF-β/Smads and MicroRNA regulation in diabetic nephropathy --- p.32 / Chapter CHAPTER TWO --- MATERIALS AND METHODS --- p.35 / Chapter 2.1 --- Materials --- p.36 / Chapter 2.1.1 --- Regents and equipment --- p.36 / Chapter 2.1.1.1 --- Reagents and equipment for cell culture --- p.36 / Chapter 2.1.1.2 --- Reagents and equipment for real-time RT-PCR --- p.37 / Chapter 2.1.1.3 --- Reagents and equipment for western blotting --- p.38 / Chapter 2.1.1.4 --- Reagents and equipment for immunohistochemistry --- p.39 / Chapter 2.1.1.5 --- Reagents and equipment for in situ hybridization --- p.40 / Chapter 2.1.1.6 --- Reagents and equipment for plasmid purification --- p.40 / Chapter 2.1.1.7 --- Reagents and equipment for genotyping --- p.41 / Chapter 2.1.1.8 --- Other reagents --- p.41 / Chapter 2.1.2 --- Buffers --- p.42 / Chapter 2.1.2.1 --- Western blotting buffer --- p.42 / Chapter 2.1.2.2 --- Immunohistochemistry buffer --- p.45 / Chapter 2.1.2.3 --- ELISA buffers --- p.47 / Chapter 2.1.2.4 --- In Situ hybridization buffer --- p.48 / Chapter 2.2.2 --- Antibodies --- p.49 / Chapter 2.2.3 --- Primer sequences --- p.49 / Chapter 2.2 --- Methods --- p.56 / Chapter 2.2.1 --- Animal model --- p.56 / Chapter 2.2.1.1 --- Animals --- p.56 / Chapter 2.2.1.2 --- Diabetic animal models --- p.57 / Chapter 2.2.2 --- Sample Collection --- p.59 / Chapter 2.2.2.1 --- Urine collection --- p.59 / Chapter 2.2.2.2 --- Plasma collection --- p.59 / Chapter 2.2.2.3 --- Tissue collection --- p.60 / Chapter 2.2.2.4 --- Paraffin embedding --- p.60 / Chapter 2.2.3 --- Ultrasound-microbubble-mediated gene transfer system --- p.61 / Chapter 2.2.3.1 --- Smad7 gene therapy --- p.61 / Chapter 2.2.3.2 --- miR-29 gene therapy --- p.62 / Chapter 2.2.4 --- Microalbumin and renal function --- p.63 / Chapter 2.2.4.1 --- Microalbuminuria --- p.63 / Chapter 2.2.4.2 --- Creatinine measurement --- p.63 / Chapter 2.2.5 --- Enzyme-Linked Immunosorbent Assay (ELISA) --- p.64 / Chapter 2.2.6 --- Histology and immunohistochemistry --- p.64 / Chapter 2.2.6.1 --- Tissue process --- p.64 / Chapter 2.2.6.2 --- Periodic Acid-Schiff Staining (PAS) --- p.64 / Chapter 2.2.6.3. --- Immunohistochemistry (IHC) --- p.65 / Chapter 2.2.6.4 --- In Situ hybridization --- p.66 / Chapter 2.2.6.5 --- Quantitation of histology and IHC --- p.67 / Chapter 2.2.7 --- Cell culture --- p.67 / Chapter 2.2.8 --- Real-time polymerase chain reaction (PCR) --- p.69 / Chapter 2.2.9 --- Western Blotting --- p.70 / Chapter 2.3 --- Statistical analysis --- p.71 / Chapter CHAPTER THREE --- THE PROTECTIVE ROLE OF SMAD7 IN DIABETIC NEPHROPATHY --- p.72 / Chapter 3.1 --- Introduction --- p.73 / Chapter 3.2 --- Materials and methods --- p.74 / Chapter 3.2.1 --- Animal models --- p.74 / Chapter 3.2.2 --- Ultrasound-mediated gene transfer of inducible Smad7 gene-bearing microbubbles into the kidney --- p.74 / Chapter 3.2.3 --- Real-time PCR --- p.75 / Chapter 3.2.4 --- Western blotting --- p.75 / Chapter 3.2.5 --- Microalbuminuria and urinary creatinine analysis --- p.76 / Chapter 3.2.6 --- Histology and immunohistochemistry --- p.76 / Chapter 3.2.7 --- Statistical analysis --- p.77 / Chapter 3.3 --- Results --- p.77 / Chapter 3.3.1 --- Genotyping for Smad7 KO and WT mice --- p.77 / Chapter 3.3.2 --- Disruption of Smad7 enhances diabetic kidney injury --- p.78 / Chapter 3.3.3 --- Disruption of Smad7 enhanced fibrosis in diabetic kidney --- p.80 / Chapter 3.3.3.1 --- Collagen I is enhanced in diabetic Smad7 KO mice --- p.81 / Chapter 3.3.3.2 --- Collagen IV is enhanced in diabetic Smad7 KO mice --- p.82 / Chapter 3.3.3.3 --- Fibronectin is enhanced in diabetic Smad7 KO mice --- p.84 / Chapter 3.3.4 --- Disruption of Smad7 exacerbates inflammation in diabetic kidney --- p.85 / Chapter 3.3.4.1 --- Disruption of Smad7 increases IL-1β in diabetic kidney --- p.85 / Chapter 3.3.4.2 --- Disruption of Smad7 increases TNF-α in diabetic kidney --- p.86 / Chapter 3.3.4.3 --- Disruption of Smad7 Increases MCP-1 in diabetic kidney --- p.87 / Chapter 3.3.4.4 --- Disruption of Smad7 increases ICAM-1 in diabetic kidney --- p.88 / Chapter 3.3.4.5 --- Disruption of Smad7 increases macrophage infiltration in diabetic kidney --- p.90 / Chapter 3.3.5 --- Enhanced activation of TGF-β/Smad3 and NF-κB Signaling is a central mechanism by which disruption of Smad7 promotes diabetic renal fibrosis and inflammation --- p.91 / Chapter 3.3.5.1 --- Smad7 decreases in diabetic kidney --- p.91 / Chapter 3.3.5.2 --- Enhanced activation of TGF-β/Smad3 signaling pathway contributes to fibrosis in diabetic kidney --- p.92 / Chapter 3.3.5.3 --- Enhanced activation of NF-κB/p65 signaling pathway contributes to inflammation in diabetic kidney --- p.93 / Chapter 3.3.6 --- Smad7 transfection rate by gene therapy in diabetic rats --- p.94 / Chapter 3.3.7 --- Restoring Smad7 attenuates kidney injury in diabetic rats --- p.96 / Chapter 3.3.8 --- Restoring Smad7 attenuates renal fibrosis in diabetic rats --- p.98 / Chapter 3.3.8.1 --- Restoring Smad7 attenuates collagen I in diabetic kidney --- p.98 / Chapter 3.3.8.2 --- Restoring Smad7 attenuates collagen IV in diabetic kidney --- p.100 / Chapter 3.3.8.3 --- Restoring Smad7 attenuates collagen III in diabetic kidney --- p.101 / Chapter 3.3.9 --- Restoring Smad7 attenuates renal inflammation in diabetic rats --- p.104 / Chapter 3.3.9.1 --- Restoring Smad7 attenuates IL-1b in diabetic kidney --- p.104 / Chapter 3.3.9.2 --- Restoring Smad7 attenuates TNF-α in diabetic kidney --- p.106 / Chapter 3.3.9.3 --- Restoring Smad7 Attenuates MCP-1 in diabetic kidney --- p.107 / Chapter 3.3.9.4 --- Restoring Smad7 attenuates ICAM-1 in diabetic kidney --- p.109 / Chapter 3.3.9.5 --- Restoring Smad7 attenuates macrophage infiltration in diabetic kidney --- p.111 / Chapter 3.3.10 --- Blockade of activation of TGF-β/Smad3 and NF-κB signaling is a key mechanism by which overexpression of smad7 inhibits diabetic renal injury --- p.113 / Chapter 3.3.10.1 --- Restoring Smad7 inhibits activation of TGF-β/Smad3 signaling --- p.113 / Chapter 3.3.10.2 --- Restoring Smad7 inhibits activation of NF-κB signaling --- p.115 / Chapter 3.3 --- Discussion --- p.117 / Chapter CHAPTER FOUR --- THE PROTECTIVE ROLE OF MICRORNA-29B IN DIABETIC NEPHROPATHY --- p.121 / Chapter 4.1 --- Introduction --- p.122 / Chapter 4.2 --- Materials and methods --- p.123 / Chapter 4.2.1 --- Animal model --- p.123 / Chapter 4.2.2 --- Ultrasound-microbubble-mediated-miR-29 gene transfer --- p.124 / Chapter 4.2.3 --- Real-time polymerase chain reaction (PCR) --- p.124 / Chapter 4.2.4 --- Western Blotting --- p.125 / Chapter 4.2.5 --- Albumin excretion measurement --- p.126 / Chapter 4.2.6 --- ELISA --- p.126 / Chapter 4.2.7 --- Histology and immunohistochemistry --- p.126 / Chapter 4.2.8 --- In Situ hybridization --- p.127 / Chapter 4.2.9 --- Cell culture --- p.128 / Chapter 4.2.10 --- Statistical analysis --- p.129 / Chapter 4.3 --- Results --- p.129 / Chapter 4.3.1 --- Over-expression of miR-29b attenuates, but knockdown of miR-29b enhances fibrosis in vitro --- p.129 / Chapter 4.3.1.1 --- Over-expression of miR-29b attenuates fibrosis --- p.129 / Chapter 4.3.1.2 --- Knockdown of miR-29b enhances fibrosis --- p.132 / Chapter 4.3.2 --- Restoring miR-29b attenuates kidney injury in db/db mice --- p.134 / Chapter 4.3.3 --- Restoring miR-29b attenuates renal fibrosis in db/db mice --- p.139 / Chapter 4.3.3.1 --- Restoring miR-29b attenuates collagen IV in db/db mice --- p.139 / Chapter 4.3.3.2 --- Restoring miR-29b attenuates collagen I in db/db mice --- p.141 / Chapter 4.3.3.3 --- Restoring miR-29b attenuates fibronectin in db/db mice --- p.144 / Chapter 4.3.4 --- Restoring miR-29b inhibits renal fibrosis via TGF-β/Smad3 dependent pathway --- p.146 / Chapter 4.3.5 --- Restoring miR-29b inhibits th1 immune response in diabetic kidney --- p.148 / Chapter 4.3.6 --- Restoring miR-29b inhibits inflammation in diabetic kidney --- p.151 / Chapter 4.4 --- Discussion --- p.154 / Chapter 4.5 --- Conclusion --- p.161 / Chapter CHAPTER FIVE --- THE PATHOGENIC ROLE OF C-REACTIVE PROTEIN IN DIABETIC NEPHROPATHY --- p.162 / Chapter 5.1 --- Introduction --- p.163 / Chapter 5.2 --- Materials and methods --- p.164 / Chapter 5.2.1 --- Mouse model of STZ induced diabetes --- p.164 / Chapter 5.2.2 --- Measurement of blood glucose, urinary albumin excretion, and creatinine clearance --- p.165 / Chapter 5.2.3 --- Histology and immunohistochemistry --- p.165 / Chapter 5.2.4 --- Cell culture --- p.166 / Chapter 5.2.5 --- Real-time PCR --- p.166 / Chapter 5.2.6 --- Western blotting --- p.167 / Chapter 5.2.7 --- Statistical analyses --- p.168 / Chapter 5.3 --- Results --- p.168 / Chapter 5.3.1 --- Diabetic renal injury is exacerbated in CRP Tg mice --- p.168 / Chapter 5.3.2 --- Renal inflammation is exacerbated in diabetic CRP Tg mice --- p.172 / Chapter 5.3.2.1 --- F4/80+ macrophage infiltration is enhanced in diabetic CRP Tg mice --- p.172 / Chapter 5.3.2.2 --- CD3+ T cell infiltration is enhanced in diabetic CRP Tg mice --- p.173 / Chapter 5.3.2.3 --- TNF-α expression is enhanced in diabetic CRP Tg mice --- p.173 / Chapter 5.3.2.4 --- IL-1β expression is enhanced in diabetic CRP Tg mice --- p.174 / Chapter 5.3.3 --- Renal fibrosis is enhanced in diabetic CRP Tg mice --- p.175 / Chapter 5.3.3.1 --- Collagen I is enhanced in Diabetic CRP Tg mice --- p.175 / Chapter 5.3.3.2 --- Collagen IV is enhanced in diabetic CRP Tg mice --- p.176 / Chapter 5.3.4 --- Enhanced CRP signaling and activation of NF-κB and TGF-β/Smad3 signaling are key mechanism by which CRP promotes diabetic renal injury --- p.177 / Chapter 5.3.4.1 --- Enhanced CRP signaling via upregulation of CD32a expression --- p.177 / Chapter 5.3.4.2 --- enhanced activation of NF-κB signaling is key mechanism by which CRP promotes renal inflammation --- p.179 / Chapter 5.3.4.3 --- Enhanced activation of TGF-β/Smad3 signaling is key mechanism by which CRP promotes renal inflammation --- p.181 / Chapter 5.4 --- Discussion --- p.194 / Chapter 5.5 --- Conclusion --- p.197 / Chapter CHAPTER SIX --- SUMMARY AND CONCLUSION --- p.198 / REFERENCES --- p.202
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Hepatoma-derived growth factor regulation of the growth, the radiosensitivity and the chemosensitivity of human cancer cells. / 肝癌衍生生長因子(HDGF)對人類癌細胞的生長, 輻射敏感性及藥物敏感性之影響 / CUHK electronic theses & dissertations collection / Gan ai yan sheng sheng zhang yin zi (HDGF) dui ren lei ai xi bao de sheng zhang, fu she min gan xing ji yao wu min gan xing zhi ying xiang

January 2008 (has links)
Hepatoma-derived growth factor (HDGF) is commonly over-expressed in human cancer cells. It was able to stimulate cell growth. The expression level of HDGF was reported to correlate with poor prognosis of cancer therapy. It was found that HDGF is over-expressed in the fractionated gamma radiation conditioned HepG2 cells, which have higher growth rate, lower radiosensitivity and higher drug sensitivity. The aim of the present study was to investigate the role of HDGF in mediating these changes in human cancer cells and the underlying mechanisms. The results indicate that transfection of HDGF cDNA carrying vector stimulated the growth of cancer cells while knock-down of HDGF by transfection of HDGF antisense oligos not only suppressed the growth but also triggered apoptosis in human cancer cells. It suggests that HDGF stimulates cancer cell growth and acts as a survival factor for human cancer cells. Mechanistic study showed that knock-down of HDGF may trigger apoptosis through the regulation of the apoptotic pathways. The apoptosis induced by HDGF knock-down was mediated by the BAD regulated intrinsic apoptotic pathway and the Fas regulated extrinsic apoptotic pathway. The HDGF knock-down induced apoptosis was also mediated by the changes in the activity of the cell survival pathways, including the Ras/Raf/MEK/ERK, PI3K/Akt, NFkappaB and Jak/STAT pathways. In addition to the growth promoting function, HDGF was found to regulate the radiosensitivity and chemosensitivity of cancer cells. Overexpression of HDGF reduced the radiosensitivity and the level of apoptosis induced by gamma radiation. On the contrast, overexpression of HDGF increased the chemosensitivity and the level of apoptosis induced by anti-cancer drugs, including Taxol, doxorubicin (Dox) and tamoxifen. The results indicated that HDGF may stimulate the growth, reduce the radiation sensitivity and increase the drug sensitivity of cancer cells. HDGF may also be responsible for the changes in cancer cell properties after fractionated gamma radiation treatment. The present findings suggest that HDGF may be a potential target for cancer therapy. / Tsang, Tsun Yee. / Adviser: Tim Tak Kwok. / Source: Dissertation Abstracts International, Volume: 70-06, Section: B, page: 3497. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2008. / Includes bibliographical references. / 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. / Abstracts in English and Chinese. / School code: 1307.

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