Dissertations / Theses on the topic '2-Cells stage'
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Pethe, Shirish. "Optimization Of The Two Stage Process For Cu(In,Ga)Se2 Solar Cells." Scholar Commons, 2004. https://scholarcommons.usf.edu/etd/1194.
Full textWang, Yejiao. "Fabrication of Cu2ZnSnSe4 Thin-film Solar Cells by a Two-stage Process." Scholar Commons, 2016. http://scholarcommons.usf.edu/etd/6154.
Full textGNOCCHI, ANDREA. "UNDERSTANDING THE IMPACT OF REPLICATION STRESS ON THE EXPRESSION OF EARLY GENES IN MOUSE EMBRYONIC STEM CELLS." Doctoral thesis, Università degli Studi di Milano, 2021. http://hdl.handle.net/2434/814703.
Full textRooj, Arun Kumar. "THE INFLUENCE OF PROBIOTIC LACTOBACILLI ON GLUCOSE UPTAKE BY CACO-2 CELLS." MSSTATE, 2007. http://sun.library.msstate.edu/ETD-db/theses/available/etd-07052007-141908/.
Full textStein, Merle [Verfasser], and Hans-Martin [Gutachter] Jäck. "A defined mitochondrial metabolic state in pre-B cells contributes to B cell homeostasis and is modulated by Swiprosin-2 / EFhd1 / Merle Stein ; Gutachter: Hans-Martin Jäck." Erlangen : Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 2016. http://d-nb.info/1114989932/34.
Full textStein, Merle Verfasser], and Hans-Martin [Gutachter] [Jäck. "A defined mitochondrial metabolic state in pre-B cells contributes to B cell homeostasis and is modulated by Swiprosin-2 / EFhd1 / Merle Stein ; Gutachter: Hans-Martin Jäck." Erlangen : Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 2016. http://d-nb.info/1114989932/34.
Full textPoirier, Luc. "The degradation of the stem-loop binding protein at the late 2-cell stage of mouse embryogenesis /." Thesis, McGill University, 2003. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=80351.
Full textLittle, Scott Alan. "Enhancement of Cu(In,Ga)Se2 Solar Cells and Materials via the Incorporation of Silver." University of Toledo / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1333734769.
Full textCarvalho, Cyntia Helena Pereira de. "Estudo in vitro dos efeitos da BMP-2 e do seu antagonista Noggin sobre a prolifera??o e migra??o celulares em carcinoma epiderm?ide de l?ngua." Universidade Federal do Rio Grande do Norte, 2014. http://repositorio.ufrn.br:8080/jspui/handle/123456789/17166.
Full textConselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico
Oral squamous cell carcinoma (OSCC) is the most prevalent malignancy in the oral cavity and reach a large number of individuals, has become an important public health problem. Studies have demonstrated changes in pathway components BMP in various types of cancers as prostate, colon, breast, gastric and OSCCs. Is the current knowledge that these proteins may exert pro-tumor effect in more advanced stages of neoplastic development coming to favor progression and invasion tumor. The inhibition of the signaling pathway BMP-2 through its antagonists, have shown positive results of antitumor activity and use of Noggin may be a novel therapeutic target for cancer. Given this evidence and the few studies with BMP-2, Noggin and OSCC, the objective of this research was to evaluate the effect of BMP-2 and its antagonist Noggin on proliferation and migration cell in line of cell cultures of human tongue squamous cell carcinoma (SCC25). The study was divided in three groups, a control group, where SCC25 cells suffered no treatment, a BMP-2 group, in which cells were treated with 100ng/ml of BMP-2 and a group of cells that were treated with 100ng/ml of Noggin. For the proliferation assay and cell cycle were established three time intervals (24, 48 and 72 hours). Proliferative activity was investigated by trypan blue and cell cycle analysis by staining with propidium iodide flow cytometry. The potential for migration / invasion of SCC25 cells was performing by a cell invasion assay using Matrigel in a 48-hour interval. The proliferation curve showed a higher proliferation in cells treated with BMP-2 in 72 hours (p < 0.05), and lower overgrowth and cell viability in Noggin group. Recombinant proteins favored a greater percentage of cells in cell cycle phase Go/G1 with a statistically significant difference in the interval of 24 hours (p < 0.05). BMP- 2 produced a greater invasion of cells studied as well as its antagonist Noggin inhibits invasion of cells (p < 0.05). Thus, these results indicate that BMP-2 promotes malignant phenotype, dues stimulates proliferation and invasion of SCC25 cells and, its antagonist Noggin may be an alternative treatment, due to inhibit the tumor progression
O carcinoma epiderm?ide oral (CEO) representa a neoplasia maligna mais prevalente na cavidade oral e por atingir um grande n?mero de indiv?duos, acaba se tornado um relevante problema de sa?de p?blica. Muitos estudos demonstram altera??es nos componentes da via BMP em v?rios tipos de tumores, como os de pr?stata, c?lon, mama, g?stricos e CEOs. ? do conhecimento atual que essas prote?nas podem exercer efeito pr?-tumoral em est?gios mais avan?ados do desenvolvimento neopl?sico vindo a favorecer a progress?o e invas?o tumoral. A inibi??o da via de sinaliza??o da BMP-2, atrav?s dos seus antagonistas, tem mostrado resultados positivos de a??o antitumoral e que assim, o uso do Noggin pode ser um novo alvo terap?utico contra o c?ncer. Diante destas evid?ncias e dos escassos trabalhos com BMP-2, Noggin e CEO, o objetivo desta pesquisa foi avaliar o efeito da BMP-2 e seu antagonista Noggin sobre a prolifera??o e migra??o celulares em culturas de c?lulas de carcinoma epiderm?ide de l?ngua humana (SCC25). Foi feita a divis?o em tr?s grupos de estudo, um grupo controle, onde as c?lulas SCC25 n?o sofriam tratamento com subst?ncia alguma, um grupo BMP-2, no qual as c?lulas eram tratadas com 100ng/ml de BMP-2 e um grupo de c?lulas que eram tratadas com 100ng/ml de Noggin. Para o ensaio de prolifera??o e ciclo celular foram estabelecidos tr?s intervalos de tempo (24, 48 e 72 horas). A atividade proliferativa foi investigada por azul de tripan e a an?lise do ciclo celular atrav?s da marca??o por iodeto de prop?dio em Citometria de fluxo. O potencial de migra??o/invas?o das c?lulas SCC25 foi avaliado atrav?s da realiza??o de um ensaio de invas?o celular utilizando o matrigel em um intervalo de 48 horas. A curva de prolifera??o revelou maior crescimento celular nas c?lulas tratadas com BMP-2 no intervalo de 72 horas (p<0.05) e menor crecimento e viabilidade celular no grupo Noggin. As prote?nas recombinantes favoreceram a maior porcentagem das c?lulas na fase do ciclo celular Go/G1 com diferen?a estatisticamente significativa no intervalo de 24 horas (p<0,05). A BMP-2 promoveu uma maior invas?o das c?lulas estudadas, assim como o seu antagonista Noggin inibiu a invas?o das c?lulas estudadas (p<0,05). Dessa forma, os resultados indicam que a BMP-2 favorece o fen?tipo maligno, pois estimula a prolifera??o e invas?o das c?lulas SCC25 e seu antagonista Noggin pode ser uma alternativa terap?utica pois inibiu essas caracter?sticas pr?-tumorais
Wallgren, Marcus. "Insight into the mitochondrial apoptotic pathway : The interplay of the pro-apoptotic Bax protein with oxidized phospholipids and its counterplayer, the pro-survival Bcl-2 protein." Doctoral thesis, Umeå universitet, Kemiska institutionen, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-61290.
Full textArcambal, Angélique. "Effet délétère de l’hyperglycémie sur la fonctionnalité des cellules endothéliales cérébrales et rôle protecteur de polyphénols antioxydants." Thesis, La Réunion, 2019. http://www.theses.fr/2019LARE0004.
Full textType 2 diabetes promotes vascular complications, leading to cerebrovascular disorders such as stroke. Indeed, hyperglycemia alters the blood-brain barrier integrity by deregulating the cerebral endothelial cell function. Oxidative stress and pro-inflammatory response may play a causal role. Thus, the biological effect of plant polyphenols known to exert antioxidant and anti-inflammatory capacities is of high interest. We evaluated the impact of hyperglycemia on the production of redox, inflammatory and vasoactive markers of cerebral endothelial cells, and the protective effect of polyphenols from the medicinal plant Antirhea borbonica from Reunion island. The murine bEnd.3 cerebral endothelial cells and an ischemia-reperfusion mouse model exposed to hyperglycemia were used. Our results demonstrated that hyperglycemia induced an oxidative stress and a pro-inflammatory state, leading to cerebral endothelial dysfunction through the activation of specific signaling molecules. Importantly, polyphenols extracted from Antirhea borbonica counteracted hyperglycemia deleterious effects and protected cerebral endothelial cells. Moreover, hyperglycemia exacerbated oxidative stress and pro-inflammatory state promoting cerebrovascular damages and loss of endothelial barrier integrity in ischemia-reperfusion mice model. Polyphenols exerted antioxidant and anti-inflammatory activities, attenuating cerebrovascular damages. These findings suggest that polyphenols extracted from Antirhea borbonica exerted protective effects on cerebral endothelial cells and an ischemia-reperfusion mouse model against deleterious effects of hyperglycemia
Soares, Andrea Ferreira. "Avalia??o da express?o da BMP -2/4 e BMPR-IA em carcinoma epiderm?ide oral metast?tico e n?o metast?tico." Universidade Federal do Rio Grande do Norte, 2007. http://repositorio.ufrn.br:8080/jspui/handle/123456789/17139.
Full textCoordena??o de Aperfei?oamento de Pessoal de N?vel Superior
The expression of bone morphogenetic proteins (BMPs) is altered in a variety of human canceres. The BMP-2/4 and BMPR-IA were recently shown to be overexpressed in high-risk premalignant and malignant lesions of oral epithelium. The present study analysed the expression of BMP-2/4 and BMPR-IA in Oral Squamous Cell Carcinoma (OSCC) such as their implications in disease prognostic using munohistochemistry. Ten cases of Oral Fibroepithelial Hiperplasia were selected as a control group. The experimental group included 16 cases of OSCC without metastases and 7 cases of OSCC metastatic. The presence or absence of nodal metastases was used as parameter to evaluated the disease prognostic. The results demonstrated weak immunoreactivity for BMP-2/4 and BMPR-IA in every case of the control group. In the cases of OSCC with metastases an overexpression of BMP-2/4 (71,4%) was observed while the BMPR-IA showed weak expression (85,7%). In the cases of OSCC without metastases BMP-2/4 (62,5%) and BMPR-IA showed strong immunostaining standing out an overexpression of the receptor in all the specimens. Observed statistical significance for correlation between the oral cancer prognostic and the staining intensity of the BMP-2/4 (p=0,002). There wasn t statistical significance for association between the staining intensity of the BMPR-IA and the disease prognostic (p<0,001). In conclusion, this findings suggest that the overexpression of BMP-2/4 associated with the loss of expression of the BMPR-IA in OSCC metastatic has prognostic relevance, as the loss of sensitivity to BMPs can be an indicative of metastases development in OSCC
A express?o das prote?nas morfogen?ticas ?sseas (BMPs) est? alterada em v?rios c?nceres humanos. A BMP-2/4 e o BMPR-IA foram recentemente encontrados superexpressos em les?es malignas e pr?-malignas de alto risco em epit?lio oral. Este estudo analisou a express?o da BMP-2/4 e seu receptor BMPR-IA em 23 esp?cimes de Carcinoma Epiderm?ide Oral (CEO), utilizando a imuno-histoqu?mica. O grupo controle constou de 10 casos de Hiperplasia Fibro-epitelial da mucosa oral. O grupo experimental foi constitu?do por 16 casos de CEO n?o metast?tico e 7 casos de CEO metast?tico. Utilizou-se o par?metro presen?a ou aus?ncia de met?stase nodal para avaliar o progn?stico da doen?a. Os resultados demonstraram imunorreatividade fraca para a BMP-2/4 e o BMPR-IA em todos os esp?cimes do grupo controle. No grupo experimental com met?stase, a BMP-2/4 exibiu forte expressividade (71,4%), enquanto que o BMPR-IA mostrou fraca express?o (85,7%). No grupo experimental sem met?stase, evidenciou-se forte express?o para a BMP-2/4 (62,5%) e para o BMPR-IA (100%). Encontrou-se signific?ncia estat?stica para a associa??o entre o progn?stico do CEO e a intensidade de marca??o da BMP-2/4 (p=0,002). Para o BMPR-IA n?o houve signific?ncia estat?stica ? sua associa??o com o progn?stico da doen?a (p<0,001), em fun??o do tamanho da amostra. Portanto, os resultados sugerem que a fraca expressividade do BMPR-IA associada ? forte express?o da BMP-2/4, no grupo experimental com met?stase, tem relev?ncia progn?stica, j? que a perda de sensibilidade ?s BMPs, atrav?s da perda de express?o de seus receptores pode ser indicativo de desenvolvimento de met?stase em CEO
Metri, Noura. "Elaboration de molécules pi-conjuguées à base de triphénylamine pour la réalisation de dispositifs photovoltaïques hybrides sensibilisés." Thesis, Cergy-Pontoise, 2011. http://www.theses.fr/2011CERG0521/document.
Full textSolid state dye-sensitized solar cells (ssDSSC) are considered as an emerging technology in order to replace conventional silicon solar cells or even those using liquid electrolyte. In order to improve the performance of ssDSSC devices, we were interested by the development of star-shaped molecules derived from thieno[3,2-b]thiophene unit and triphenylamine core.Two series of new substituted triphenylamine (TPA) derivatives with thiophene and thieno[3,2-b]thiophene units (with and without nonyl group C9H19) were synthesized in a combinatorial manner. These compounds were obtained by Stille or Suzuki coupling with a yield between 11% and 37% (from six to ten steps).In order to determine the properties of these compounds, thermal, optical and electrochemical characterizations were carried out. The measurements by thermogravimetric analysis (TGA) showed a high stability of the compounds above 340°C. Differential thermal analysis (DSC) was used to determine the glass transition temperature (Tg) where the highest reaching 57°C. The optical and electronic gaps were determined by UV-Visible absorption ( we found from 2.87 eV to 2.41 eV in film) or cyclic voltammetry (we found from 3.26 eV to 2.60 eV). The energy levels of HOMO and LUMO were also determined by cyclic voltammetry. They showed adequate levels especially for HOMO levels (ideally HOMO between the dye and that of the cathode) for a photovoltaic application. Finally, hole mobility have shown encouraging results and promising ranging from 10-3 cm2.V-1.s-1 and 1 cm2.V-1.s-1.The theoretical study of these molecules was also carried out using molecular modeling as B3LYP. The energy levels (HOMO and LUMO), the optical gaps, and the energy of internal reorganization (giving an idea of the theoretical charges mobility) have the seam trend overlap the experimental data.The photovoltaic performance of these compounds was performed. An efficiency of 0.5% (not optimized results) has been obtained for the best of them. This efficiency was sustainable after one year. The pore filling ratio of this compound in TiO2 reached from 62 to 83%.Keywords : Solid state dye-sensitized solar cells (ssDSSC), triphenylamine, thieno[3,2-b]thiophene, thiophene, molecular glasses, theoretical calculations, pore filling
Hamy, Anne-Sophie. "Identification of Factors Predicting Sensitivity or Resistance to Neoadjuvant Chemotherapy in Breast Cancer Neoadjuvant treatment : the future of patients with breast cancer Neoadjuvant treatment for intermediate/high-risk HER2-positive and triple-negative breast cancers: no longer an “option” but an ethical obligation Long-term outcome of the REMAGUS 02 trial, a multicenter randomised phase II trial in locally advanced breast cancer patients treated with neoadjuvant chemotherapy with or without celecoxib or trastuzumab according to HER2 status BIRC5 (survivin) : a pejorative prognostic marker in stage II/III breast cancer with no response to neoadjuvant chemotherapy Beyond Axillary Lymph Node Metastasis, BMI and Menopausal Status Are Prognostic Determinants for Triple-Negative Breast Cancer Treated by Neoadjuvant Chemotherapy Pathological complete response and prognosis after neoadjuvant chemotherapy for HER2-positive breast cancers before and after trastuzumab era: results from a real-life cohort The presence of an in situ component on pre-treatment biopsy is not associated with response to neoadjuvant chemotherapy for breast cancer Chemosensitivity, tumor infiltrating lymphocytes (TILs), and survival of postpartum PABC patients treated by neoadjuvant chemotherapy Lymphovascular invasion after neoadjuvant chemotherapy is strongly associated with poor prognosis in breast carcinoma New insight for pharmacogenomics studies from the transcriptional analysis of two large-scale cancer cell line panels Biological network-driven gene selection identifies a stromal immune module as a key determinant of triple-negative breast carcinoma prognosis A Stromal Immune Module Correlated with the Response to Neoadjuvant Chemotherapy, Prognosis and Lymphocyte Infiltration in HER2-Positive Breast Carcinoma Is Inversely Correlated with Hormonal Pathways Stromal lymphocyte infiltration after neoadjuvant chemotherapy is associated with aggressive residual disease and lower disease-free survival in HER2-positive breast cancer Interaction between molecular subtypes, stromal immune infiltration before and after treatment in breast cancer patients treated with neoadjuvant chemotherapy COX2/PTGS2 Expression Is Predictive of Response to Neoadjuvant Celecoxib in HER2-negative Breast Cancer Patients Celecoxib With Neoadjuvant Chemotherapy for Breast Cancer Might Worsen Outcomes Differentially by COX-2 Expression and ER Status: Exploratory Analysis of the REMAGUS02 Trial Comedications influence immune infiltration and pathological response to neoadjuvant chemotherapy in breast cancer." Thesis, Université Paris-Saclay (ComUE), 2019. http://www.theses.fr/2019SACLS129.
Full textNeoadjuvant chemotherapy (NAC i.e. chemotherapy before surgery) is increasingly being used for aggressive or locally advanced breast cancer (BCs). Beyond clinical benefits, it represents an opportunity to monitor in vivo sensitivity to treatment. Based on the analysis of datasets of BCs patients treated with NAC, we aimed at identifying mechanisms associated with resistance or sensitivity to treatment.In the first part, we evaluated biological, clinical, pathological and transcriptomic patterns. We demonstrated that unexplored pathological features such as post-NAC lymphovascular invasion may carried an important prognostic information.In a second part, we analyzed impact of imune infiltration in BC and we described extensively the changes of tumor infiltrating lymphocytes (TILs) between pre and post-NAC samples. We showed that the prognostic impact of TILs was different before and after NAC, and was opposite in TNBC and HER2-positive BCs. Finally, we investigated the impact of comedications use during NAC. We found both positive effects - while enhancing immune infiltration and response to treatment - and negative effects with deleterisous oncologic outcomes in specific patients subgroups. In conclusion, the neoadjuvant setting represents a platform to both generate and potentially validate research hypotheses aiming at increasing the efficacy of treatment. The public release of real-life datasets of BC patients treated with NAC would represent a major resource to accelerate BC research
Ou-Yang, Huan, and 歐陽桓. "Promoter assay of Granzyme g in mouse 2-cell stage embryonic development." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/56611441213248427098.
Full text國立臺灣大學
動物科學技術學研究所
102
Mouse Granzyme g (Gzmg) is an important protease and specificitly expressed at 2-cell stage of mouse embryo. Maternal zygotic transition (MZT) that control from maternal massage to synthesize zygotic gene products promote preimplantation embryo development in mouse 2-cell stage. It is demonstrated that zygotic RNA synthesize is blocked in Gzmg knock-down 2-cell embryo. These data indicated that Gzmg is a necessary protein in MZT. Thus, we want to know what mechanisms regulate Gzmg specific expression in mouse embryo 2-cell stage. We cloned full-length Gzmg promoter from mouse genomic DNA, FL-pGzmg (-1696 ~ +28nt), and generated four deletion constructs of Gzmg promoter, Δ1- (-1369 ~ +28nt), Δ2- (-939 ~ +28nt), Δ3- (-711 ~ +28nt) and Δ4-pGzmg (-417 ~ +28nt). We replaced CMV promoter of pEGFP-N1 with Gzmg promoter. Furthermore, we co-microinjected different types of Gzmg promoter constructs and pCMV-IRES2-mCherry vector into zygote pronuclear, 2-cell nuclear and also added an aphidicolin drug to arrest the embryo cell cycle in S phase. We predicted transcription factor binding sites in promoter sequence by JASPAR and expression atlas website. The immunofluorescence method can observe transcription factors location in mouse preimplantation embryo. We found the highest EGFP expression Δ4-pGzmg-EGFP, but lower expression level in FL and Δ1-pGzmg-EGFP in both zygote pronuclear and 2-cell nuclear injection. This result demonstrated that time-specific transcriptional factors up-regulated Gzmg transcription activity by binding cis-element in -417~+28nt of Gzmg promoter sequence. In addition, The JASER database and expression atlas website revealed that Gabpa and Stat3 were predicted that may up-regulate Gzmg in 2-cell stage. Futhermore, Gabpa and Stat3 located in zygote and 2-cell nuclear by immunofluorescence. These data supposed that Gabpa and Stat3 may had transcriptional activity of regulatory genes in zygote and 2-cell stage. Surprisingly, we observed that Gabpa and Stat3 co-localized with Δ4-pGzmg-EGFP. -939~+28nt of Gzmg promoter sequence had cis-element that controled Gzmg transcription activity, and Gabpa and Stat3 may up-regulate Gzmg in 2-cell stage. Thus, Gabpa and Stat3 are maternal proteins and may up-regulate Gzmg to promote MZT.
Lin, William, and 林殿威. "Analysis of mouse 2-cell stage zygote-specific granzyme G gene express profile." Thesis, 2001. http://ndltd.ncl.edu.tw/handle/13468024072576690646.
Full text國立中興大學
生物化學研究所
89
The purpose of this study was to identify genes expressed in the different developmental stage of mouse embryo after onset of their oestrus. Total RNA samples were extracted from ICR mouse fertilized eggs, which had been induced to super-ovulation by administration of gonadotrophins, at various time at 24, 48 and 72 post-hCG injection. Each RNA samples was subjected to analysis by method of differential display reverse transcription-polymerase chain reaction (DDRT-PCR) with a total of 40 primer sets comprised of anchor and arbitrary primers. One of these clones, expressed at 48h post-hCG injection, was possess a sequence 100% homology to that of gene coding for the serine protease, granzyme G. Granzymes family (granzyme A-H,K,M) are serine proteases present in secretory granules of cytolytic T lymphocyte lines. Granzyme D-G showed to be expressed in late gestation at mouse uterus. There is no report about granzyme G expressed so early, 2-cell stage, at mouse embryo. It is interesting that any gene expression in pre-implantation embryo may involve in the initiated of embryonic genomic DNA. Granzyme G could the one of whose “pull the trigger” to help mouse embryo development continually. We used the microinjection of morpholino antisense oligos into the two pro-nucleus(2PN) stage embryo to block the expressing of granzyme G, compared with culture medium injected, standard control oligo injected and in vitro culture without any treatment. This antisense oligo treatment will be disclose the granzyme G that involved in possibly functions of the early development of mouse embryos
Comfort, Kristen Krupa. "Intracellular signaling networks in the immune response: pathways activated by interleukin-2 and interleukin-4 receptors and their roles in T cell proliferation /." 2006. http://www.lib.ncsu.edu/theses/available/etd-06032006-202720/unrestricted/etd.pdf.
Full textIeronimo, Marco [Verfasser]. "Towards the activity of the antimicrobial peptide PGLa in cell membranes : solid state 19F-NMR studies of PGLa and magainin 2 / von Marco Ieronimo." 2008. http://d-nb.info/989376117/34.
Full textTeixeira, Ana Andreia Mendes. "Study of NAD metabolism in protein aggregation." Master's thesis, 2018. http://hdl.handle.net/10773/25054.
Full textNAD (Nicotinamida Adenina Dinucleótido) é uma piridina envolvida em vários processos biológicos, nomeadamente, catabolismo de nutrientes que sustentam a produção de energia na célula. Durante o envelhecimento, os níveis de NAD diminuem e uma desregulação global da proteostase é observada. Como muitas doenças ligadas ao envelhecimento são neurodegenerativas, onde ocorre acumulação de agregados de proteínas, colocamos a hipótese que o NAD poderá prevenir ou melhorar a agregação proteica. Para estudar o papel do metabolismo do NAD na proteostase, expusemos células SH-SY5Y a químicos que modelam os níveis de agregação proteica e de NAD. As células foram marcadas com o kit ProteoStat® para detetar os agregados proteicos e analisadas por citometria de fluxo e microscopia confocal. A viabilidade celular foi medida com iodeto de propídio por citometria de fluxo e o estado metabólico foi medido usando o ensaio colorimétrico da resazurina. Células SH-SY5Y apresentaram um aumento de agregados proteicos na presença do inibidor de proteossoma MG132 ao longo do tempo. MG132 induziu mais agregação do que o tratamento com um inibidor do metabolismo de NAD, no entanto a suplementação com NAD pareceu diminuir esses agregados. A microscopia confocal corroborou os resultados de citometria de fluxo. Em todas as condições testadas, a viabilidade celular não foi alterada, em contraste com o estado metabólico que foi alterado pelos tratamentos. Suplementação com NAD pareceu diminuir a agregação proteica e estudos futuros serão necessários para elucidar o papel na proteostase dos diferentes precursores de NAD e vias metabólicas associadas.
Mestrado em Biomedicina Molecular
Umerska, A., Krzysztof J. Paluch, M. J. Santos-Martinez, C. Medina, O. I. Corrigan, and L. Tajber. "Chondroitin-based nanoplexes as peptide delivery systems-Investigations into the self-assembly process, solid-state and extended release characteristics." Thesis, 2015. http://hdl.handle.net/10454/9416.
Full textA new type of self-assembled polyelectrolyte complex nanocarrier composed of chondroitin (CHON) and protamine (PROT) was designed and the ability of the carriers to bind salmon calcitonin (sCT) was examined. The response of sCT-loaded CHON/PROT NPs to a change in the properties of the liquid medium, e.g. its pH, composition or ionic strength was studied and in vitro peptide release was assessed. The biocompatibility of the NPs was evaluated in Caco-2 cells. CHON/PROT NPs were successfully obtained with properties that were dependent on the concentration of the polyelectrolytes and their mixing ratio. X-ray diffraction determined the amorphous nature of the negatively charged NPs, while those with the positive surface potential were semi-crystalline. sCT was efficiently associated with the nanocarriers (98-100%) and a notably high drug loading (13-38%) was achieved. The particles had negative zeta potential values and were homogenously dispersed with sizes between 60 and 250 nm. CHON/PROT NPs released less than 10% of the total loaded peptide in the first hour of the in vitro release studies. The enthalpy of the decomposition exotherm correlated with the amount of sCT remaining in NPs after the release experiments. The composition of medium and its ionic strength was found to have a considerable influence on the release of sCT from CHON/PROT NPs. Complexation to CHON markedly reduced the toxic effects exerted by PROT and the NPs were compatible and well tolerated by Caco-2 cells.