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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

Critical Roles of microRNA-141-3p and CHD8 in Hypoxia/Reoxygenation-Induced Cardiomyocyte Apoptosis

Yao, Bifeng, Wan, Xiaoya, Zheng, Xinbin, Zhong, Ting, Hu, Jia, Zhou, Yu, Qin, Anna, Ma, Yeshuo, Yin, Deling 21 February 2020 (has links)
Background: Cardiovascular diseases are currently the leading cause of death in humans. The high mortality of cardiac diseases is associated with myocardial ischemia and reperfusion (I/R). Recent studies have reported that microRNAs (miRNAs) play important roles in cell apoptosis. However, it is not known yet whether miR-141-3p contributes to the regulation of cardiomyocyte apoptosis. It has been well established that in vitro hypoxia/reoxygenation (H/R) model can follow in vivo myocardial I/R injury. This study aimed to investigate the effects of miR-141-3p and CHD8 on cardiomyocyte apoptosis following H/R. Results: We found that H/R remarkably reduces the expression of miR-141-3p but enhances CHD8 expression both in mRNA and protein in H9c2 cardiomyocytes. We also found either overexpression of miR-141-3p by transfection of miR-141-3p mimics or inhibition of CHD8 by transfection of small interfering RNA (siRNA) significantly decrease cardiomyocyte apoptosis induced by H/R. Moreover, miR-141-3p interacts with CHD8. Furthermore, miR-141-3p and CHD8 reduce the expression of p21. Conclusion: MiR-141-3p and CHD8 play critical roles in cardiomyocyte apoptosis induced by H/R. These studies suggest that miR-141-3p and CHD8 mediated cardiomyocyte apoptosis may offer a novel therapeutic strategy against myocardial I/R injury-induced cardiovascular diseases.
12

Avaliação da expressão dos microRNAs-184, -190a-5p e -493-3p e sua correlação com o controle das crises epilépticas em pacientes operados por Epilepsia do Lobo Temporal Mesial / Evaluation of the microRNAs 184, -190a-5p and -493-3p expression and its correlation with epileptic crises control in Mesial Temporal Lobe Epilepsy operated patients

Silvestre, Renata Nacasaki 23 May 2016 (has links)
Introdução: A epilepsia pode ser considerada uma desordem neurológica causada pela anormalidade da transmissão de impulsos nervosos, devido ao aumento da excitação nervosa e/ou diminuição da sua inibição. Dentre as síndromes epilépticas, destaca-se a Epilepsia do Lobo Temporal Mesial (ELTM) devido a sua alta prevalência e refratariedade ao tratamento medicamentoso. Com intuito de implementar novas possibilidades de tratamento torna-se necessário uma maior compreensão das bases moleculares da ELTM. Dentro desta perspectiva, destacam-se os microRNAs, que possuem papel regulatório nas células, inclusive as do Sistema Nervoso Central. Com base em dados da literatura e num experimento de microarray, realizado no laboratório de Biologia Molecular do Departamento de Cirurgia e Anatomia da Faculdade de Medicina de Ribeirão Preto, foram escolhidos 3 dos 10 microRNAs, cujos alvos preditos estão relacionados à epileptogênese e que se apresentam diferencialmente expressos em hipocampos de pacientes com ELTM. Objetivos: avaliar a expressão diferencial de três microRNAs de interesse em hipocampos de pacientes operados por ELTM refratária ao tratamento clínico a fim de correlacionar os resultados em relação aos controles das crises epilépticas após a cirurgia. Metodologia: Foram utilizadas 15 amostras de hipocampo de pacientes com ELTM classificados como Engel I (boa evolução - nenhuma ou poucas crises convulsivas após lobectomia temporal parcial) e 15 amostras de hipocampos de pacientes classificados como Engel III/IV (má evolução - sem melhora evidente após tratamento cirúrgico). Como controles, foram utilizadas 10 amostras de hipocampo de pacientes sem doenças neurológicas, obtidas de necropsias do Serviço de Patologia do Hospital das Clínicas de Ribeirão Preto (HCFMRP). Por meio de técnica de PCR quantitativo em tempo real (RT-qPCR) foram realizadas as avaliações das expressões diferenciais dos seguintes microRNAs: miR-184, miR-190a-5p e miR-493-3p. Resultados: Em relação aos controles, o miR-184 e o miR190a-5p apresentaram-se, respectivamente, com redução significativa (p = 0,001) e com tendência a baixa expressão (p = 0,24) nos hipocampos de pacientes com ELTM. No que se refere ao controle das crises, o miR-184 apresentou-se significativamente mais expresso nos hipocampos de pacientes com pior evolução (Engel III/IV vs Engel I, p = 0,003). A expressão do miR-493-3p não se correlacionou com o controle de crises com significância estatística. Conclusão: Dentro os microRNAs avaliados, a expressão do miR-184, que possui importante papel na regulação de componentes celulares relacionados a apoptose e morte celular, correlacionou-se inversamente com o controle das crises após cirurgia (mais expresso em pacientes com má evolução) tornando-se potencial biomarcador e com valor preditivo / Introduction: Epilepsy is a neurological disorder caused by nerve impulse transmission abnormalities, by increasing nerve excitation and/or decreasing nerve inhibition. Among the epileptic syndromes, one of the most important ones is Mesial Temporal Lobe Epilepsy (MTLE) due to its high prevalence and resistance to drug treatment. A greater understanding of the epilepsy molecular basis is necessary aiming to implement new treatments possibilities. Within this field of study, it is possible to highlight the microRNA molecules, which have a regulatory role in cell regulation including in the Central Nervous System (CNS). Based on literature data and in an microarray experiment, performed in the Anatomy and Surgery Departament Molecular Biology laboratory of the Ribeirao Preto Medical School, we have chosen three out of ten microRNAs, with predicted targets related to epileptogenesis and that presented themselves differencially expressed in patients hippocampus with MTLE. Objective: To evaluate three microRNAs of interest which were differentially expressed in the hippocampus of MTLE drug-resistant operated patients in order to correlate the results with the clinical evolution based on the seizures control after surgery. Methodology: Fifteen hippocampus samples from patients with MTLE classified as Engel I (good evolution - without seizures or few seizures after surgical resection) and 15 samples from patients classified as Engel III/IV (bad evolution - no evident improvement after surgery) were used in this study. In the control group, we used ten samples of hippocampus fragments from patients without neurological diseases, that were obtained from the Ribeirao Preto Clinical Hospital Pathology and Legal Medicine Service. The differential expression validation from microRNAs-184, -190a-5p and -493-3p were performed by quantitative real time PCR (RT-qPCR) technique. Results: Regarding the controls, miR-184 and miR- 190a-5p showed, respectively, a significant expression reduction (p=0,001) and a decreased expression tendency (p=0,24) in MTLE patients. If we consider seizure control, miR-184 presented itself significantly upregulated in bad evolution hippocampus patients (Engel III/IV vs Engel I, p=0,003). miR-493-3p did not show expression differences with statistical significance. Conclusions: After evaluating the expression of these microRNAs, it was possible to conclude that microRNA-184, which regulates cellular death and apoptosis related components, was the best molecule that could differentiate the patients regarding seizure control after surgery, and that fact makes this microRNA a potential biomarker with predictive value
13

Avaliação da expressão dos microRNAs-184, -190a-5p e -493-3p e sua correlação com o controle das crises epilépticas em pacientes operados por Epilepsia do Lobo Temporal Mesial / Evaluation of the microRNAs 184, -190a-5p and -493-3p expression and its correlation with epileptic crises control in Mesial Temporal Lobe Epilepsy operated patients

Renata Nacasaki Silvestre 23 May 2016 (has links)
Introdução: A epilepsia pode ser considerada uma desordem neurológica causada pela anormalidade da transmissão de impulsos nervosos, devido ao aumento da excitação nervosa e/ou diminuição da sua inibição. Dentre as síndromes epilépticas, destaca-se a Epilepsia do Lobo Temporal Mesial (ELTM) devido a sua alta prevalência e refratariedade ao tratamento medicamentoso. Com intuito de implementar novas possibilidades de tratamento torna-se necessário uma maior compreensão das bases moleculares da ELTM. Dentro desta perspectiva, destacam-se os microRNAs, que possuem papel regulatório nas células, inclusive as do Sistema Nervoso Central. Com base em dados da literatura e num experimento de microarray, realizado no laboratório de Biologia Molecular do Departamento de Cirurgia e Anatomia da Faculdade de Medicina de Ribeirão Preto, foram escolhidos 3 dos 10 microRNAs, cujos alvos preditos estão relacionados à epileptogênese e que se apresentam diferencialmente expressos em hipocampos de pacientes com ELTM. Objetivos: avaliar a expressão diferencial de três microRNAs de interesse em hipocampos de pacientes operados por ELTM refratária ao tratamento clínico a fim de correlacionar os resultados em relação aos controles das crises epilépticas após a cirurgia. Metodologia: Foram utilizadas 15 amostras de hipocampo de pacientes com ELTM classificados como Engel I (boa evolução - nenhuma ou poucas crises convulsivas após lobectomia temporal parcial) e 15 amostras de hipocampos de pacientes classificados como Engel III/IV (má evolução - sem melhora evidente após tratamento cirúrgico). Como controles, foram utilizadas 10 amostras de hipocampo de pacientes sem doenças neurológicas, obtidas de necropsias do Serviço de Patologia do Hospital das Clínicas de Ribeirão Preto (HCFMRP). Por meio de técnica de PCR quantitativo em tempo real (RT-qPCR) foram realizadas as avaliações das expressões diferenciais dos seguintes microRNAs: miR-184, miR-190a-5p e miR-493-3p. Resultados: Em relação aos controles, o miR-184 e o miR190a-5p apresentaram-se, respectivamente, com redução significativa (p = 0,001) e com tendência a baixa expressão (p = 0,24) nos hipocampos de pacientes com ELTM. No que se refere ao controle das crises, o miR-184 apresentou-se significativamente mais expresso nos hipocampos de pacientes com pior evolução (Engel III/IV vs Engel I, p = 0,003). A expressão do miR-493-3p não se correlacionou com o controle de crises com significância estatística. Conclusão: Dentro os microRNAs avaliados, a expressão do miR-184, que possui importante papel na regulação de componentes celulares relacionados a apoptose e morte celular, correlacionou-se inversamente com o controle das crises após cirurgia (mais expresso em pacientes com má evolução) tornando-se potencial biomarcador e com valor preditivo / Introduction: Epilepsy is a neurological disorder caused by nerve impulse transmission abnormalities, by increasing nerve excitation and/or decreasing nerve inhibition. Among the epileptic syndromes, one of the most important ones is Mesial Temporal Lobe Epilepsy (MTLE) due to its high prevalence and resistance to drug treatment. A greater understanding of the epilepsy molecular basis is necessary aiming to implement new treatments possibilities. Within this field of study, it is possible to highlight the microRNA molecules, which have a regulatory role in cell regulation including in the Central Nervous System (CNS). Based on literature data and in an microarray experiment, performed in the Anatomy and Surgery Departament Molecular Biology laboratory of the Ribeirao Preto Medical School, we have chosen three out of ten microRNAs, with predicted targets related to epileptogenesis and that presented themselves differencially expressed in patients hippocampus with MTLE. Objective: To evaluate three microRNAs of interest which were differentially expressed in the hippocampus of MTLE drug-resistant operated patients in order to correlate the results with the clinical evolution based on the seizures control after surgery. Methodology: Fifteen hippocampus samples from patients with MTLE classified as Engel I (good evolution - without seizures or few seizures after surgical resection) and 15 samples from patients classified as Engel III/IV (bad evolution - no evident improvement after surgery) were used in this study. In the control group, we used ten samples of hippocampus fragments from patients without neurological diseases, that were obtained from the Ribeirao Preto Clinical Hospital Pathology and Legal Medicine Service. The differential expression validation from microRNAs-184, -190a-5p and -493-3p were performed by quantitative real time PCR (RT-qPCR) technique. Results: Regarding the controls, miR-184 and miR- 190a-5p showed, respectively, a significant expression reduction (p=0,001) and a decreased expression tendency (p=0,24) in MTLE patients. If we consider seizure control, miR-184 presented itself significantly upregulated in bad evolution hippocampus patients (Engel III/IV vs Engel I, p=0,003). miR-493-3p did not show expression differences with statistical significance. Conclusions: After evaluating the expression of these microRNAs, it was possible to conclude that microRNA-184, which regulates cellular death and apoptosis related components, was the best molecule that could differentiate the patients regarding seizure control after surgery, and that fact makes this microRNA a potential biomarker with predictive value
14

An Investigation of Formation and Operation Mechanisms on R&D Alliances ¡V A Case Study of Steel Industry

Chan, Chen-Feng 21 August 2008 (has links)
The R&D alliance becomes a popular way to develop products by cooperating with external organizations in the face of severe global competition. The enterprises can improve core competence and reduce environmental uncertainty through R&D alliances. However, the success rate of alliance is not high. Consequently, how to organize and operate R&D alliances effectively and successfully is the key competence of enterprise to win in the future. In order to increase the success rate of R&D alliance, the purpose of this study is to create a conceptual and integrated model for developing the successful mechanisms of formation and operation on R&D alliances. VPDCA (Vision-Plan-Do-Check-Action) cycle was developed as a conceptual framework through literature survey and case study for investigating the successful mechanisms of formation and operation on R&D alliances, which is to be regarded as a ¡¥learning by doing¡¦ process. First of all, vision leading is the first step to assure alliance to be succeeded. SSO (Search-Select-Organize) was developed as a successful process model for organizing R&D alliances. R&D alliance operation was regarded as a teamwork operation in this study. Only has the good effective team operation, can achieve expected vision. LICTEL (Leadership-Integration-Communication-Trust-Execution-Learning) was considered as the key aspects to run alliances successfully. The key success factors of each aspect are as follows: Leadership: vision, inspiration vitality, integrity and delegation Integration: open, linkage, collaboration, leverage outside resources, synergy Communication: dialogue, open mind, passion, patience and positive thinking Trust: co-value, cooperation, communication, consensus and commitment Execution: discipline, push and pull Learning: connect, interaction and share The achievements of operation and management on R&D alliance should be evaluated finally. 3P (Pleasure-Performance-Profit) was considered as key measures to evaluate the outcomes of R&D alliance implementation. Furthermore, effectiveness, efficiency and competence build-up are regarded as key measures to evaluate implementation performance of R&D alliance.
15

Methodology for capturing environmental, social and economic implications of industrial symbiosis in heavy industrial areas

Kurup, Biji R. January 2007 (has links)
Industrial operations have been attributed to causing social and environmental problems such as: acid rain; greenhouse gas emissions, air, water and soil pollution; plus health problems to neighbourhood communities. With the 3P (people, planet, profit) approach for sustainability as the background, there have been movements to establish the concept of eco-industrial development in existing or new industrial areas from the planning stage onwards. Industrial ecology (IE) is the operation of an industrial ecosystem which is based on the principles of operation of a natural ecosystem. Industrial symbiosis (IS), one of the principal applications of IE, is defined as inter-firm collaboration, where a network of industries collaborates in exchange of products, by-products, information, resources and wastes to reduce their collective environmental footprint to achieve mutual benefits. / Industrial symbiosis is a collaborative process of industries geographically located in an industrial park, which facilitates and enables an exchange of products, by-products and wastes to reduce the collective adverse impacts of the emission during the operation of these industries. However, IS faces a number of barriers. Importantly, it has been identified that there is a critical impediment to implementing future IS practices in the area. This is because of the number of barriers such as technical, regulatory, commercial as well as informational. In addition, there is an absence of a proven and well established evaluation methodology to identify the benefits of such practice. The true implications of IS might therefore remain underestimated, thereby failing to convince industry, government and the community to realize the opportunities IS can bring in attaining goals of sustainability in their operations. / The aim of this PhD research was to develop and trial a method for capturing the life cycle environmental, social and economic implications of industrial symbiosis in heavy industrial areas. This research was based on multi-disciplinary approach of examining environmental, social and financial aspects to develop an integrated method. In the Kwinana industrial Area (KIA), the primary research area in Western Australia, the opportunities were significant for such industrial symbiosis to happen because of the co-location of diverse industries. The research hypothesis that informs this thesis is that the assessment of implications of present IS might bring further opportunities for enhancing symbiosis between industries. Though the primary emphasis of the research was in the Kwinana Industrial Area, this approach could be applied to other heavy industrial areas. This site could be significant both nationally and internationally in providing a platform for business responses to regional sustainable development challenges, by documenting best practice and improving approaches for implementing industrial symbiosis. / This research addressed the objectives by using the developed Six Capitals Model (SCM) for identifying environmental, social and economic benefits. The values under these dimensions were analysed with regard to natural, ecosystem, human, social, financial and manufactured capitals for a project of wastewater reclamation for industrial use. Under the environmental dimension, the model revealed that resource conservation and resource security were achieved as a result of the operation of this project. These results are in line with the argument that industrial symbiosis secures and conserves resources due to the possibility of reclaiming the resources that were once discarded. Water contamination has been reduced as a result of the operation of this project. This indicator shows that there is an improvement in maintaining the ecosystem capital. / In terms of human capital, sharing information between industries and opportunities of sharing infrastructure and technology has been improved. Regarding community capital, sharing of information between industries and communities, has increased as a result of this project. Collaboration of government bodies, level of understanding about IS projects due to increasing communication between various stakeholders, and increase of employment opportunities are notable, as value has been generated for community capital since the project started. In terms of financial capital of the project, the majority of the participants did not gain any financial savings in terms of direct costs but rather accrued short term costs. This was due to the infrastructure cost involved as part of installation of pipes and pumps. It was also due to the high cost of the reclaimed water than the scheme water. In addition, the analysis showed that most of the participants of the project did not gain any savings in the indirect costs such as hidden and legal costs, such as permit costs, compliance costs, future fines and penalties. However, as part of manufactured capital, there were savings due to improved business opportunities as well as infrastructure, for business and community collectively. / The results of this thesis show that broader benefits of symbiosis can be achieved, not only from operation of the project, but also from the influence of processes of symbiosis. Among them are connection, communication and collaboration between the project partners. There has been a substantial increase in the networking of industries and formation of multi groups for addressing various issues faced by industry and community in the Kwinana. There has also been a further increase in the transparency of information dissemination and communication through industries council’s website. In addition, there has been an improvement in the rate of participation of community members and groups in the Communities and Industries Forum (CIF) which resulted in the formation of further stakeholder groups by industries council as a platform for addressing the issues of industries and communities. / IS practices strengthen the EIP concept and increase the chances of sustainable industrial development regionally due to collaboration of community of businesses and local and regional community. IS also increases the reputation and license to operate in the community. There are many advantages for using the Model developed in the thesis to assess the benefits of IS. First, the values of ecosystem values maintained are able to be accounted for in addition to natural capital values. The Six Capital Model can also account human capital values in addition to community capital. The Model also accounted the manufactured capital in addition to financial capital and it gives an opportunity to identify the value generated towards community and companies. / Finally, the Model enables a calculation of the internal costs and external costs and benefits so that industries are able to understand the real cost of the projects. One of the main advantages of this method is that with, right indicators, the intangible values of the IS process can also be assessed and reported.
16

SERUM MICRORNA 362-3P AS A POTENTIAL BIOMARKER TO PREDICT THE EXTENT OF DRUG-INDUCED QT INTERVAL LENGTHENING AMONG HEART FAILURE PATIENTS

Rakan JAMAL Alanazi (6922283) 14 December 2020 (has links)
Background: The sensitivity to drug-induced QT prolongation is highly variable in heart failure (HF) patients. QT interval prolongation can lead to a life-threatening ventricular arrhythmia known as torsade de Pointes (TdP), which can result in sudden cardiac death. Although QT prolongation is a surrogate marker for sudden cardiac death, the extent of drug-induced QT prolongation, and thus TdP, is largely unpredictable. Therefore, developing a biomarker to predict patients’ sensitivity to drug-induced QTc prolongation could have a profound clinical impact. MicroRNA (miR) are recognized as important regulators of cardiovascular function as they shape the transcriptome by targeting mRNAs for repression of translation. Our multidisciplinary research group has demonstrated that miR-362-3p regulates a potassium channel (i.e., hERG) that is the most widely implicated in drug-induced QTc prolongation. The primary objects of this analysis focus on characterizing serum miR-362-3p expression in the circulation as a potential biomarker to predict subject’s susceptibility to ibutilide exposure induced QT-interval prolongation.<div><br></div><div>Methods: The dataset utilized to develop the PK-PD models were collected from a previous clinical study carried out by Tisdale et al. (Tisdale,et al. 2020).A total of 22 adult subjects who met the inclusion and exclusion criteria were enrolled and divided into three groups: a group of patients with heart failure with preserved ejection fraction (HFpEF, n=10), a group of patients with heart failure with reduced ejection fraction (HFrEF, n=2), and ten healthy subjects in the control group who were matched to subjects in the HFpEF group for age and sex. Following a baseline day of triplicate 12-lead ECGs, all subjects received ibutilide 0.003mg/kg intravenously infused over 10 minutes. Serial collection of blood samples to determine serum Ibutilide concentrations (HPLC/MS), serum miR-362-3 expression (qPCR), with triplicate ECG readings were obtained pre-and-post ibutilide administration. To describe ibutilide serum concentration exposure and the9relationship with Fridericia-corrected QT (QTF) intervals, a non-linear mixed effect modeling approach was used along with clinical and demographic data, and serum miR-362-3p expression was evaluated as potential covariates on the PK/PD model.<div><br></div><div>Results: A three-compartment model best described the time course of ibutilide concentrations profile with a proportional residual error. The individual ibutilide concentrations time profile was then used in an indirect response model where ibutilide concentrations are indirectly driving the QT interval prolongation through inhibition of the output (Kout) parameters linked to an indirect response model with zero‐order input parameter best described the ibutilide concentrations QT interval lengthening relationship. The Individual PK/PD parameters using the base model for the Imax and IC50 were 11.4% (9.9%RES) and 0.36(8.4% RES)ng/mL, respectively. Following stepwise forwarding inclusion steps, the final covariate analyses identified circulating miR-362-3p expression associated with a history of myocardial infarction covariate influencing both the Imax and IC50( p<0.05). <div><br></div><div>Conclusions: An indirect response model has been developed to describe the effects of ibutilide concentrations on QT-intervals. Although the semi-mechanistic model could not be developed; serummiR-362-3p expression was identified as a significant predictor for ibutilide-induced QT-interval prolongation. Moreover, the upregulation of serum miR-362-3p expression enhanced IC50 seen after ibutilide administration. The potential use of miR-362-3p as a biomarker warrants further investigation to identify patients at the greatest risk of TdP </div></div></div>
17

Modelado de la cardiotoxicidad inducida por antraciclinas en hiPSC-CM de pacientes oncológicos pediátricos y estudio del papel cardioprotector del miR-4732-3p

Reinal Ferré, Ignacio 03 May 2023 (has links)
[ES] Las antraciclinas son fármacos antineoplásicos ampliamente utilizados en el trata-miento de varios tipos de cáncer, incluyendo tanto tumores sólidos como hematoló-gicos. A pesar de su eficacia, su uso se ve limitado por su efecto cardiotóxico. El aumento de los supervivientes de cáncer, especialmente pediátrico, ha provocado que cada vez haya más personas con cardiotoxicidad inducida por antraciclinas. Por este motivo, es necesaria la búsqueda de nuevos modelos de enfermedad relevan-tes para comprender la fisiopatología del daño cardíaco inducido por antraciclinas, así como el desarrollo de nuevas terapias cardioprotectoras que permitan el uso de las antraciclinas evitando su efecto cardiotóxico. En este trabajo se ha estudiado, por una parte, la susceptibilidad al daño por do-xorrubicina (una de las principales antraciclinas empleadas en clínica) de cardiomio-citos obtenidos a partir de células madre pluripotentes inducidas derivadas de pa-cientes pediátricos oncológicos que experimentaron cardiotoxicidad causada por an-traciclinas. Los cardiomiocitos de los pacientes fueron tratados con doxorrubicina y se evaluaron diferentes parámetros, incluyendo la viabilidad, apoptosis, estrés oxida-tivo, daño genómico, daño mitocondrial, desorganización sarcomérica, etc. compa-rándolos con cardiomiocitos control. Nuestros resultados mostraron que estos car-diomiocitos recapitulan la susceptibilidad a la doxorrubicina observada en los pacien-tes, constituyendo un buen modelo de enfermedad para estudiar los mecanismos de cardiotoxicidad de la doxorrubicina o el cribado de fármacos. Por otra parte, se ha evaluado el papel cardioprotector de un miARN, el miR-4732-3p, frente al daño inducido por antraciclinas. Este miARN está desregulado en pa-cientes con cáncer de mama que sufrieron cardiotoxicidad inducida por antraciclinas. Para comprobar su efecto cardioprotector, este miARN fue sobreexpresado en célu-las cardíacas de rata, las cuales fueron tratadas con doxorrubicina, observándose que incrementaba la supervivencia de las células y reducía el estrés oxidativo. Tam-bién se estudió la cardioprotección in vivo en un modelo de cardiotoxicidad inducida por doxorrubicina en rata, observando que mejora la función cardíaca, reduce la fi-brosis intersticial y el estrés oxidativo. Además, se hizo un estudio de los posibles genes diana de este miARN. En su conjunto, nuestros resultados muestran que el miR-4732-3p tiene un efecto cardioprotector frente al daño por doxorrubicina, y po-dría ser una herramienta terapéutica para el tratamiento del daño cardíaco causado por las antraciclinas. / [CAT] Les antraciclines són fàrmacs antineoplàstics àmpliament utilitzats en el tractament de diversos tipus de càncer, incloent tant tumors sòlids com hematològics. Tot i la seva eficàcia, el seu ús es veu limitat pel seu efecte cardiotòxic. L'augment dels su-pervivents de càncer, especialment pediàtric, ha provocat que cada cop hi hagi més persones amb cardiotoxicitat induïda per antraciclines. Per aquest motiu, cal cercar nous models de malaltia rellevants per comprendre la fisiopatologia del dany cardíac induït per antraciclines, així com el desenvolupament de noves teràpies cardiopro-tectores que permetin l'ús de les antraciclines evitant-ne l'efecte cardiotòxic. En aquest treball s'ha estudiat, d'una banda, la susceptibilitat al dany per doxorrubi-cina (una de les principals antraciclines emprades en clínica) de cardiomiòcits obtin-guts a partir de cèl¿lules mare pluripotents induïdes derivades de pacients pediàtrics oncològics que van experimentar cardiotoxicitat causada per antraciclines. Els cardi-omiòcits dels pacients van ser tractats amb doxorrubicina i es van avaluar diferents paràmetres, incloent-hi la viabilitat, apoptosi, estrès oxidatiu, dany genòmic, dany mitocondrial, desorganització sarcomèrica, etc. comparant-los amb cardiomiòcits control. Els nostres resultats van mostrar que aquests cardiomiòcits recapitulen la susceptibilitat a la doxorrubicina observada en els pacients, constituint un bon model de malaltia per estudiar els mecanismes de cardiotoxicitat de la doxorrubicina o el cribratge de fàrmacs. D'altra banda, s'ha avaluat el paper cardioprotector d'un miARN, el miR-4732-3p, davant del dany induït per antraciclines. Aquest miARN està desregulat en pacients amb càncer de mama que van patir cardiotoxicitat induïda per antraciclines. Per comprovar el seu efecte cardioprotector, aquest miARN va ser sobreexpressat en cèl·lules cardíaques de rata, les quals van ser tractades amb doxorrubicina, obser-vant-se que incrementava la supervivència de les cèl·lules i reduïa l'estrès oxidatiu. També es va estudiar la cardioprotecció in vivo en un model de cardiotoxicitat induï-da per doxorrubicina en rata, observant que millora la funció cardíaca, redueix la fi-brosi intersticial i l'estrès oxidatiu. A més, es va fer un estudi dels possibles gens di-ana d'aquest miARN. En conjunt, els nostres resultats mostren que el miR-4732-3p té un efecte cardioprotector davant el dany per doxorrubicina, i podria ser una eina terapèutica per al tractament del dany cardíac causat per les antraciclines. / [EN] Anthracyclines are drugs widely used in the treatment of several types of cancer, including both solid tumors and hematologic malignancies. Despite its proven effica-cy, its use is hampered by its cardiotoxic effect. The increase in cancer survivors, especially pediatric, has led to more and more people with anthracycline-induced cardiotoxicity. Therefore, it is necessary to search for new relevant disease models to better understand the physiopathology of cardiac damage-induced by anthracy-clines, as well as the development of new cardioprotective therapies that allow the clinic use of anthracyclines avoiding their cardiotoxic effect. In this work we have studied, on the one hand, the susceptibility against doxorubicin damage (major anthracycline used in clinic) of cardiomyocytes obtained from in-duced pluripotent stem cells derived from oncology pediatric patients that underwent cardiotoxicity-induced by anthracyclines. Cardiomyocytes from these patients were treated with doxorubicin, and we evaluated several parameters, including cell viabil-ity, apoptosis, oxidative stress, genomic damage, mitochondrial damage, sarcomere disorganization, etc. comparing the results with control cardiomyocytes. Our results showed that these cardiomyocytes recapitulate the susceptibility against doxorubicin observed in the patients, making them a good disease model to study cardiotoxicity mechanisms of doxorubicin or drug screening. On the other hand, we evaluated the cardioprotective role of one miRNA, miR-4732-3p, against doxorubicin-induced damage. This miRNA is dysregulated in breast can-cer patients that suffered cardiotoxicity-induced by anthracyclines. To test its cardio-protective effect, this miRNA was overexpressed in rat cardiac cells that were treated with doxorubicin, showing an increment of cell survival and a reduction of oxidative stress levels. We also studied in vivo cardioprotection in a doxorubicin-induced cardi-otoxicity model in rat, showing an improvement in cardiac function, reduced intersti-tial fibrosis and reduced oxidative stress levels. Moreover, we studied possible target genes of this miARN. Overall, our results showed that miR-4732-3p has a cardiopro-tective role against doxorrubicin-induced damage and could be used as a therapeutic tool for treatment of cardiac damage caused by anthracycline. / Reinal Ferré, I. (2023). Modelado de la cardiotoxicidad inducida por antraciclinas en hiPSC-CM de pacientes oncológicos pediátricos y estudio del papel cardioprotector del miR-4732-3p [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/193075
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Development of a student-centred evaluation framework for environmental vocational education and training courses : development and validation of a student-centred evaluation framework for environmental vocational education and training courses derived from Biggs' 3P Model and Kirkpatrick's Four Levels Evaluation Model

Draper, Fiona Jane January 2012 (has links)
Individuals and organisations need to do much more if sustainable development is to be achieved. Appropriate environmental vocational education and training (EVET) is essential for current decision makers. Crucial decisions need to be made before the present generation of school and college students achieve significant positions of authority. An increasing range of EVET courses and course providers are available within the UK. However, availability is not synonymous with suitability for either the attendee and/or his/her (future) employer. Previous research indicates that, as a component of lifelong learning, EVET courses should and the methods used to evaluate them should be student-centred. This thesis describes the development and validation of a new studentcentred evaluation framework. Preliminary literature reviews identified six fundamental issues which needed to be addressed. Existing academically productive evaluation models were examined and critically appraised in the context of these problems. The output from this process was used to develop a bespoke research methodology. Empirical research on four commercial EVET programmes revealed distinct personal, teaching and work-based presage factors which influenced course attendance, individual learning and subsequent organisational learning. Modified versions of Biggs¿ 3P model and Kirkpatrick¿s Four level Evaluation Model were shown to provide an effective student-centred evaluation framework for EVET courses. Additional critical elements pertaining course utility and the student¿s long(er) term ii retention of knowledge/skill were derived from previous research by Alliger et al (1997). Work-based presage factors and the student¿s return on expectation were added as a direct consequence of this research. The resultant new framework, the Presage-Product Evaluation Framework, was positively received during an independent validation. This confirmed inter alia that the framework should also be capable of adaption for use with other VET courses. Recommendations for additional research focus on the need to demonstrate this through further empirical studies.
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Placental vascular smooth muscle cell differentiation in pregnancies complicated by obesity and gestational diabetes

Whittle, Saxon January 2016 (has links)
The increasing demand on healthcare from pregnancies complicated by gestational diabetes (GDM) and obesity is caused in large part by fetal macrosomia (FM). Alterations to the vasculature of the placenta leading to changes to nutrient flux may be more frequent when GDM and obesity occur concomitantly. However, the impact of obesity as an independent comorbidity is poorly understood. The current study sought to characterise structural and functional changes in placenta from pregnancies complicated by GDM and/or obesity and examine the involvement of miRs in this phenomenon, as the phenotype of vascular smooth muscle (VSM) has been documented to be influenced by microRNA (miR) expression. Patients were stratified according to the presence or absence of GDM and/or obesity, which resulted in four groups. Morphometric analysis of CD31 immuno-stained placentas showed that pregnancies complicated by GDM or obesity both had a higher mean sum ratio of the area of the lumen compared to the endothelium. No relationship was found with FM. The ratio increased with maternal body mass index (BMI) in all pregnancies. Immunohistochemistry with a panel of VSM markers suggested an altered phenotype of VSM in pregnancies complicated by GDM and/or obesity. RT-QPCR and immunoblotting showed a higher expression of smooth muscle myosin (SM-MHC), h-caldesmon (HC) and alpha smooth muscle actin (ASMA) in pregnancies complicated by obesity, consistent with a greater contractile capacity. This was most marked when obesity occurred without GDM.Studies were conducted on two miRs, miR-145, which is associated with VSM in many vascular tissues, and the snoRNA-derived species miR-664a-3p, which microarray studies had shown to be higher in placentas from pregnancies complicated by GDM. Dicer and dyskerin, components of the snoRNA-derived miR biogenesis pathway, were increased and reduced respectively in GDM placenta. However, studies in cultured placental villous explants suggested that neither miR species was regulated by glucose, insulin or IGF-I. Placental mesenchymal cells are the developmental precursors of VSM. In primary culture, these cells expressed both miRs. To determine the function of miR-664a-3p, a nucleofection protocol was developed in a fetal mesenchymal cell line, WI38, and applied to first-trimester placental mesenchymal cells. Preliminary proteomic analysis after nucleofection-mediated knockdown of miR-664a-3p suggested a series of novel candidate target proteins for this uncharacterised miR species. Blood vessel structure and VSM phenotype are both altered in pregnancies complicated by GDM and/or obesity. The significance of apparently higher level of contractile proteins with wider vessel lumens in obesity requires further investigation. Translational regulation by miRs including miR-145 and miR-664a-3p is implicated in these alterations. In future, targeted therapies that alter miR levels in the placenta may be useful in control of fetal overgrowth such as FM.
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Development of a Student-Centred Evaluation Framework for Environmental Vocational Education and Training Courses. Development and validation of a Student-Centred Evaluation Framework for Environmental Vocational Education and Training Courses derived from Biggs' 3P Model and Kirkpatrick's Four Levels Evaluation Model.

Draper, Fiona J. January 2012 (has links)
Individuals and organisations need to do much more if sustainable development is to be achieved. Appropriate environmental vocational education and training (EVET) is essential for current decision makers. Crucial decisions need to be made before the present generation of school and college students achieve significant positions of authority. An increasing range of EVET courses and course providers are available within the UK. However, availability is not synonymous with suitability for either the attendee and/or his/her (future) employer. Previous research indicates that, as a component of lifelong learning, EVET courses should and the methods used to evaluate them should be student-centred. This thesis describes the development and validation of a new studentcentred evaluation framework. Preliminary literature reviews identified six fundamental issues which needed to be addressed. Existing academically productive evaluation models were examined and critically appraised in the context of these problems. The output from this process was used to develop a bespoke research methodology. Empirical research on four commercial EVET programmes revealed distinct personal, teaching and work-based presage factors which influenced course attendance, individual learning and subsequent organisational learning. Modified versions of Biggs' 3P model and Kirkpatrick's Four level Evaluation Model were shown to provide an effective student-centred evaluation framework for EVET courses. Additional critical elements pertaining course utility and the student's long(er) term ii retention of knowledge/skill were derived from previous research by Alliger et al (1997). Work-based presage factors and the student¿s return on expectation were added as a direct consequence of this research. The resultant new framework, the Presage-Product Evaluation Framework, was positively received during an independent validation. This confirmed inter alia that the framework should also be capable of adaption for use with other VET courses. Recommendations for additional research focus on the need to demonstrate this through further empirical studies.

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