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Efeito do carvedilol na prevenção da cardiotoxicidade por antraciclinas: estudo randomizado, duplo-cego, placebo controlado (CECCY Trial) / Effect of carvedilol in the prevention of chemotheraphyinduced cardiotoxicity: results of a randomized, double blind, placebocontrolled trialGrinberg, Mônica Samuel Avila 23 November 2018 (has links)
Introdução: O tratamento quimioterápico com antraciclina está associado à cardiotoxicidade. Sua prevenção primária com o uso de beta-bloqueadores permanece controversa. O objetivo do presente estudo é avaliar o papel do carvedilol na prevenção da cardiotoxicidade relacionada ao tratamento com antraciclina. Métodos: estudo randomizado, duplo-cego, placebo controlado que incluiu 200 pacientes com câncer de mama, fração de ejeção ventricular esquerda (FEVE) preservada e uso de doxorrubicina (240 mg/m²) para receber carvedilol ou placebo até a conclusão da quimioterapia em proporção 1:1. O desfecho primário foi a redução > 10% da FEVE em seis meses. Os desfechos secundários foram o efeito do carvedilol nos marcadores de injúria miocárdica, troponina I (TnI) e peptídeo natriurético cerebral (BNP), e na disfunção diastólica. Resultados: O desfecho primário ocorreu em 14 (14,5%) pacientes do grupo carvedilol e em 13 (13,5%) do grupo placebo (p=1,0). Não houve diferença nos valores da FEVE durante o tratamento quimioterápico ou nos valores de BNP entre os grupos. Houve diferença significativa entre os grupos na distribuição dos níveis de TnI ao longo do tempo, com menor pico de TnI no grupo carvedilol (p=0,003). Além disso, houve menor incidência de disfunção diastólica no grupo carvedilol (p=0,039). Foi observada tendência para menor aumento do diâmetro diastólico do ventrículo esquerdo do início do tratamento até o final da quimioterapia no grupo carvedilol em relação ao placebo, respectivamente, 44,1+3,64 a 45,2+3,2 vs 44,9+3,6 a 46,4+4,0 mm (p=0,057). Conclusão: A incidência de cardiotoxicidade com o uso de doses contemporâneas de ANT foi menor do que relatado previamente com doses mais elevadas. Neste cenário, a administração de carvedilol resultou em redução significativa da injúria miocárdica avaliada pelos níveis de troponina I e pelo aparecimento da disfunção diastólica. No entanto, essa redução não teve impacto na disfunção sistólica relacionada à cardiotoxicidade (NCT01724450) / Background: Anthracycline (ANT) chemotherapy is associated with cardiotoxicity. Its prevention with beta-blockers remains controversial. The aim of this prospective, randomized, double-blind, placebo-controlled study was to evaluate the role of carvedilol in the prevention of early onset ANT cardiotoxicity. Methods: We randomized 200 patients with breast cancer and normal left ventricular ejection fraction (LVEF) referred for doxorubicin (240 mg/m²) to receive carvedilol or placebo until completion of chemotherapy. The primary end-point was a reduction > 10% in LVEF at six months. Secondary outcomes were the effects of carvedilol on troponin I (TnI), BNP and diastolic dysfunction. Results: Primary end-point occurred in 14 (14.5%) patients in the carvedilol and in 13 (13.5%) in the placebo (p=1.0). No difference in changes of LVEF or BNP was noted between groups. There was a significant difference between groups on the TnI levels over time, with lower TnI levels in carvedilol group (p=0.003). Additionally, a lower incidence of diastolic dysfunction was seen in carvedilol group (p=0.039). A trend towards less pronounced increase in LV end-diastolic diameter during follow up was noted in the carvedilol group, respectively 44.1+3.64 to 45.2+3.2 vs 44.9+3.6 to 46.4+4.0 mm (p=0.057). Conclusion: In this largest clinical trial of ?-blockers for prevention of early onset cardiotoxicity under contemporary doses of ANT, we noted a lower incidence of cardiotoxicity than higher doses. In this scenario, the use of carvedilol resulted in a significant reduction in troponin levels and diastolic dysfunction. However, this reduction had no impact on the incidence of cardiotoxicity-related myocardial systolic dysfunction (NCT01724450)
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Estudo do mecanismo de ação da bromocriptina e de antagonistas de prolactina no tratamento do Diabetes Mellitus tipo 2 e da obesidade. / The study of the mechanisms of action of bromocriptine and prolactin antagonists to treat Type 2 Diabetes Mellitus and Obesity.Furigo, Isadora Clivatti 21 October 2016 (has links)
Atualmente, é crescente o interesse em estudar o potencial do Sistema Nervoso Central (SNC) como alvo de medicamentos antidiabéticos, uma vez que ele possui receptores de insulina e desempenha papel crítico na regulação da homeostase glicêmica. Nesse sentido, o Cycloset® (mesilato de bromocriptina de liberação rápida), um medicamento de ação central aprovado nos Estados Unidos para o tratamento do DMT2, atende a essa tendência atual. Trabalhos prévios mostram efeitos benéficos da bromocriptina (Bromo) sobre a hiperglicemia e hiperlipidemia em modelos de animais obesos tratados com essa droga. Por ser um agonista dopaminérgico, um dos possíveis mecanismos de ação dessa droga pode ser bloqueando a liberação e produção de prolactina (Prl). Níveis elevados de prolactina na circulação sanguínea, observados tanto em indivíduos com prolactinomas como em pessoas tratadas com medicamentos que causam hiperprolactinemia, geram anormalidades no metabolismo de carboidratos e lipídeos, o que pode levar a um quadro de síndrome metabólica. Na presente tese, testamos a hipótese de que ao menos parte dos efeitos antidiabéticos da Bromo seja mediada pela inibição da secreção de prolactina. Avaliamos os efeitos do tratamento com Bromo em camundongos machos e fêmeas geneticamente obesos e resistentes à insulina (ob/ob), bem como testamos se os efeitos benéficos do medicamento seriam revertidos com a reposição de Prl. Machos tratados com Bromo apresentaram maior sensibilidade à insulina, enquanto que a reposição de Prl manteve os animais menos sensíveis, tais como os animais do grupo controle. As fêmeas tratadas com Bromo apresentaram tendência à melhora de sensibilidade à insulina, bem como foram mais tolerantes à glicose, sendo que a reposição de Prl em animais tratados com Bromo também reverteu o efeito benéfico do medicamento. Dessa forma, demonstramos que ao menos parte dos efeitos antidiabéticos da Bromo é mediada pela inibição da secreção basal de Prl. Em um segundo conjunto de experimentos, testamos se a administração de antagonistas de prolactina (G129R-hPrlR) em machos ob/ob, por vias centrais ou periféricas, produziria efeito antidiabético. Observamos que tanto o tratamento periférico como o central diminui a curva glicêmica dos animais em testes de tolerância à glicose e melhoram a sensibilidade à insulina, embora ainda não tenhamos obtido valores significativos devido a nossa amostragem. Por fim, investigamos se a ação da Prl sobre o metabolismo ocorre por meio da interação com o receptor de estrógeno alfa (ERα). Verificamos que receptores de prolactina e de ERα são expressos em áreas comuns no SNC e que variações nos níveis circulantes de estrógeno causam mudanças na sensibilidade à prolactina. Portanto, no presente trabalho, identificamos o possível mecanismo pelo qual a Bromocriptina promove melhorias no controle glicêmico e, de forma inédita, produzimos evidências que o uso de antagonistas de prolactina pode ter potencial no tratamento do DMT2. / Type 2 Diabetes mellitus (T2DM) is a syndrome characterized by dysfunctions in the metabolism of glucose, amino acids and free fat acids. Although most of the drugs currently used to treat T2DM targets peripheral organs, a growing interest in studying the Central Nervous System (CNS) as a potential target of antidiabetic drugs is appearing. The CNS possesses insulin receptors and plays a critical role in regulating glucose homeostasis. In this sense, Cycloset® (quick release bromocriptine mesylate) a drug that acts on CNS, was recently approved in United States to treat T2DM. Previous studies have shown beneficial effects of bromocriptine (Bromo) on hyperglycemia and hyperlipidemia in obese animal models. As a dopaminergic agonist, a possible mechanism of action of this drug could be caused by a decreased prolactin (Prl) production and release. High serum prolactin levels, as observed in patients bearing prolactinomas or individuals using drugs that induce hyperprolactinemia, generate abnormalities in carbohydrate and lipid metabolism, which can lead to metabolic syndrome. In the current thesis, we tested the hypothesis that part of bromocriptine antidiabetic effects is due to an inhibition of prolactin secretion. We evaluated Bromo effects in genetically obese and insulin resistant male and female mouse (ob/ob), as well as we tested whether replacing Prl could reverse the beneficial effects of Bromo. Males treated with Bromo showed lower insulin resistence, whereas Prl replacement decreased insulin sensitivity. Females treated with Bromo showed tendency towards an improvement in their insulin sensitivity and glucose tolerance. Prl replacement also reversed the beneficial effects of Bromo in this group. Thus, we demonstrated that at least part of the antidiabetic effects of Bromo is due to inhibition of Prl secretion. In another set of experiments, we tested whether central or peripheral treatment with prolactin antagonists (G129R-hPrlR) causes antidiabetic effects in ob/ob male mice. Both peripheral and central treatment decreased the glycemic curve during glucose and insulin tolerance tests, although we still did not obtain statistically significant values with our sample size. Lastly, we investigated whether metabolic Prl action occurs due to a putative interaction with estrogen receptor alpha (ERα). We found a wide co-expression between Prl receptor and ERα in the CNS. Additionally, changes in estrogen levels decrease prolactin sensitivity. Therefore, in the present study we identified the possible mechanism by which bromocriptine promotes improvements in glycemic control, and for the first time, we obtained evidence that the use of prolactin antagonists can have a potential effect in the treatment of T2DM.
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Efeito da terapia com Beta-bloqueadores em camundongos com deleção dos receptores alpha 2A/alpha 2C adrenérgicos / Effects of b- adrenergic antagonist therapy in mice lacking a 2A/a 2C adrenergic receptorsBartholomeu, Jan Barbosa 08 August 2006 (has links)
Recentemente foi descrito que a deleção dos receptores a2A e a2C adrenérgicos em camundongos, proporciona hiperatividade simpática com evidências de insuficiência cardíaca (IC) aos sete meses de idade. Com isso, esses animais representam um modelo experimental para o estudo de diferentes terapias da IC. Estudamos o efeito de antagonistas b-adrenérgicos (BB) de diferentes gerações em camundongos deleção para os receptores a2A e a2C adrenérgicos (KO) entre cinco a sete meses de idade que apresentam mortalidade de 50%. Foram utilizados camundongos controle (CO) (n = 22) e KO (n = 94) divididos randomicamente e tratados por dois meses com salina, propranolol (P), metoprolol (M) e carvedilol (C). Foi avaliada a pressão arterial, freqüência cardíaca (FC), além da tolerância ao esforço (TE) e fração de encurtamento (FS) do ventrículo esquerdo. A estrutura cardíaca foi avaliada pelo diâmetro dos cardiomiócitos (DC) e a fração de colágeno cardíaco (CC). Aos sete meses de idade os KO tratados com salina apresentaram intolerância ao esforço e redução de 30% na FS, e aumento do DC (13%) quando comparados com os CO. Todos os BB foram eficientes em reduzir a FC de repouso dos KO que tornaram-se semelhantes as dos CO. Nenhum BB restabeleceu a TE nos animais KO. P, M e C restauraram de forma similar a FS nos KO. Apesar de todos os BB reduzirem DC, apenas M restabeleceu as dimensões dos cardiomiócitos que passaram a ser semelhantes as dos CO. Em contrapartida, apenas M reduziu parcialmente o CC. M e C reduziram a mortalidade dos KO em 31 %, sendo que o tratamento com propranolol reduziu a mortalidade dos KO em apenas 24% e foi o BB menos tolerado. Os dados evidenciam o beneficio de M e C no tratamento da IC, e sugerem maior estudo das propriedades farmacodinâmicas de M sobre o remodelamento cardíaco. / We have recently reported that disruption for both a2A ?and a2C adrenergic receptor subtypes in mice (KO) leads to sympathetic hyperactivity with evidence of heart failure (HF) by the age of 7 months. These mice provide a model system for evaluating the efficiency among different ?- adrenergic antagonists (BB) for HF therapy. In the present study, we evaluate the effect of three different BB in a cohort of a wild type (n=22) control group (WT) and a cohort of congenic KO (n=94) from five to seven mo of age. Mice from both groups were randomly assigned to receive by gavage (seven days/wk) either saline (S), propranolol (P), metoprolol (M), or carvedilol (C). Exercise capacity was measured using a graded treadmill protocol. Blood pressure (BP) and heart rate (HR) were determined by tail cuff and LV function by echocardiography. The cardiomyocyte width (CW) and cardiac collagen content (CC) were evaluated by light microscopy. At seven mo of age, when cardiac dysfunction is severe, KO treated with S displayed exercise intolerance and 30% decrease in fractional shortening (FS) when compared with WT. In addition, CW (13%) was increased. All BB were efficient in reducing baseline HR of KO mice towards WT levels, however P was less tolerated. Again, all BB similarly restored FS, and reduced CW, but only M reduced CW towards WT levels. Only M significantly decreased CC. M and C decreased mortality rate of KO mice (31 %), while P did decrease it in only 24%. Collectively these data provide direct evidence for beneficial effect of M and C in restoring cardiac function. Further investigation is need to better understand the pharmacodynamics of M on cardiac remodeling
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Predictive biomarkers of the efficacy of epidermal growth factor receptor tyrosine kinase Inhibitors in treating advanced non-small cell lung cancer: a systematic review of randomized controlled trials = 表皮生长因子受体酪氨酸激酶抑制剂治疗晚期非小细胞肺癌的疗效预测生物标志物 : 随机对照试验的系统综述. / 表皮生长因子受体酪氨酸激酶抑制剂治疗晚期非小细胞肺癌的疗效预测生物标志物: 随机对照试验的系统综述 / Predictive biomarkers of the efficacy of epidermal growth factor receptor tyrosine kinase Inhibitors in treating advanced non-small cell lung cancer: a systematic review of randomized controlled trials = Biao pi sheng zhang yin zi shou ti luo an suan ji mei yi zhi ji zhi liao wan qi fei xiao xi bao fei ai de liao xiao yu ce sheng wu biao zhi wu : sui ji dui zhao shi yan de xi tong zong shu. / Biao pi sheng zhang yin zi shou ti luo an suan ji mei yi zhi ji zhi liao wan qi fei xiao xi bao fei ai de liao xiao yu ce sheng wu biao zhi wu: sui ji dui zhao shi yan de xi tong zong shuJanuary 2014 (has links)
目的: 尽管过去几十年癌症的化疗取得了很大进步,但晚期非小细胞肺癌的预后仍然较差。表皮生长因子受体酪氨酸激酶抑制剂(epidermal growth factor receptor tyrosine kinase inhibitors,EGFR TKIs)给晚期非小细胞肺癌的患者带来了新的希望。然而,EGFR TKIs的总体效果有限,且不良反应较多,价格也较昂贵。如果能找到EGFR TKIs的疗效预测因子,则该治疗就可以只给予那些最有可能从中获益的人,从而提高成本效果,并使治疗变得更加个体化。 / 已有单组研究在接受EGFR TKIs治疗的患者中对有或没有某个标志物的人的预后进行了比较,发现EGFR基因突变、EGFR基因拷贝数增加、EGFR蛋白表达和KRAS基因突变这4个生物标志物可能能够预测EGFR TKIs的疗效。然而,此类研究的方法学是有缺陷的。要确定以上生物标志物是否有预测作用,应该在评估EGFR TKIs疗效的随机对照试验中作亚组分析,对该治疗在有某个生物标志物及没有某个生物标志物的患者中的疗效进行比较,检测治疗与生物标记物的交互作用。 / 但是,现有的随机对照试验通常样本量较小,统计效能不足,难以从中得到确定的结论。因此,我们做了一个随机对照试验的系统综述,以总结现有的最佳证据,对EGFR TKIs与上述4个生物标志物的交互作用进行评估。 / 方法: 我们检索了PubMed,EMBASE,考科蓝图书馆,中国生物医学文献数据库(中文),万方数据库(中文),美国临床肿瘤学会和欧洲肿瘤学会的会议摘要,以及相关原始研究、系统综述与Meta分析、临床指南、共识及专家意见的参考文献。检索时间截至2012年6月。合格研究为非重复、提供了具体数据且符合下列所有条件的研究:1)研究对象:晚期非小细胞肺癌患者;2)干预措施:EGFR TKIs单药治疗或联合其他药物治疗;3)对照措施:安慰剂对照,空白对照或化疗,或者它们任一种加上干预组的基线治疗;4)结局指标:无进展生存期和/或总生存期;5)研究设计:随机对照试验;6)根据上述任一种或多种生物标志物的状态作了亚组分析。 / 两名研究者平行独立地从合格研究中提取了患者特征、治疗方案、结局、生物标志物分析和方法学质量等方面的资料。对每一个研究,我们都根据生物标志物阳性亚组的风险比(hazard ratio)和阴性亚组的风险比计算了一个风险比之比(ratio of hazard ratios)来测量该标志物对疗效的预测能力或者说治疗与该生物标志物的交互作用。然后,采用随机效应模型对来自不同研究的风险比之比进行Meta分析;采用Cochran Q检验和I²评估研究间的异质性;通过敏感性分析考察原始研究的方法学质量等因素对结果的影响;采用Begg漏斗图和Egger检验来检测发表偏倚存在的可能性。 / 结果: 共有18个合格研究入选。可用于各个生物标志物分析的患者数量从1763到3246不等。原始研究普遍对关于方法学质量的信息报告得不够充分;有的研究可能存在重要偏倚。与安慰剂相比,EGFR TKIs可以有效延长无进展生存期和总生存期,但对总生存期的效果相对较小。除了在EGFR基因突变的患者中EGFR TKIs延长无进展生存期的效果明显好于化疗外,其它情形下,不管是无进展生存期还是总生存期,EGFR TKIs与化疗的效果均相当。 / 以无进展生存期为结局的风险比之比,在EGFR基因突变状态不同的亚组间(野生型亚组为参照)为0.37(95% 置信区间[CI]:0.22-0.60,P < 0.0001),EGFR基因拷贝数状态不同的亚组间(未增加的亚组为参照)为0.72(95% CI:0.52-0.99,P = 0.04),EGFR蛋白表达状态不同的亚组间(无表达的亚组为参照)为0.99(95% CI:0.78-1.26,P = 0.93),KRAS基因突变状态不同的亚组间(野生型亚组为参照)为1.35(95% CI:1.02-1.80,P = 0.04)。这些结果提示EGFR TKIs治疗与EGFR基因突变,EGFR基因拷贝数及KRAS基因突变之间可能存在交互作用。以总生存期为结局的风险比之比,在EGFR基因突变、EGFR基因拷贝数、EGFR蛋白表达及KRAS基因突变状态不同的亚组间分别为0.84(95% CI:0.64-1.11,P = 0.22)、0.92(95% CI:0.69-1.23,P = 0.57)、0.86(95% CI:0.70-1.05,P = 0.14)和1.37(95% CI:0.89-2.10,P = 0.15)。 / 就统计学显著性、异质性和稳定性而言,关于其它3个生物标志物的结果不如EGFR基因突变的相关结果确定,关于总生存期的结果不如无进展生存期的相关结果确定。没有证据表明本研究中存在发表偏倚。 / 结论: EGFR基因突变可用于确定哪些患者更有可能从EGFR TKIs治疗中获益。EGFR基因拷贝数增加和KRAS基因突变可能也有类似用途,但它们与治疗的交互作用是独立存在的还是由于它们与EGFR基因突变的相关性而获得的,目前尚不清楚。在EGFR野生型的患者中,选择化疗似乎比EGFR TKIs更好,因为它的副作用相对较少,且更为便宜。 / 本研究的结果为当前的临床指南提供了全面的证据支持。其它3个标志物在EGFR野生型患者中的预测价值可能还值得进一步的探讨,但我们更建议未来的研究在探讨治疗与生物标志物的交互作用时进行多因素分析。 / Objective: Despite the many new progresses in chemotherapy, the prognosis of advanced non-small cell lung cancer (NSCLC) remains poor. The introduction of epidermal growth factor receptor tyrosine kinase inhibitors (EGFR TKIs) seems to offer new promises for advanced NSCLC patients. However, EGFR TKIs have a limited overall efficacy, clear adverse events and large costs. It has become particularly appealing to identify, through new biomarkers, patients who are more likely to benefit from the treatment so that the treatment can be more personalized and effective. / EGFR mutations, EGFR gene copy number gain, EGFR protein expression and KRAS mutations were indicated as potential predictive biomarkers for the efficacy of the treatment in single-arm studies that compared survival of treated patients with and without a biomarker. However, such comparisons are flawed and the appropriate study design to evaluate the value of a biomarker in predicting efficacy which is known as interaction in epidemiology is the randomized controlled trial with stratified analysis that compared the efficacy of EGFR TKIs between patients with and without the biomarker. / As trials in this field are usually small in sample size and insufficiently powered for drawing a robust conclusion, we conducted this systematic review to summarize the evidence from all relevant randomized controlled trials that have data for investigating the interaction between EGFR TKIs and the 4 biomarkers. / Methods: PubMed, EMBASE, the Cochrane Library, Chinese Biomedical Literature Database (in Chinese), Wanfang Data (in Chinese), the abstracts of conferences of the American Society of Clinical Oncology and European Society of Medical Oncology, the reference list of relevant original studies, systematic reviews and meta-analyses, guidelines, consensus, and expert opinions were searched up to June 2012. / Eligible studies had to be non-duplicate, extractable studies meeting all the following criteria: 1) Population: patients with advanced NSCLC; 2) Intervention: EGFR TKIs alone or EGFR TKIs plus other treatments; 3) Control: placebo, no treatment, or chemotherapy, with or without the baseline treatments in the intervention arm; 4) Outcome: progression-free survival and/or overall survival; 5) Study design: randomized controlled trial; 6) Subgroup analyses were conducted according to the status of one or more of the 4 biomarkers. / Data on patients’ characteristics, treatment protocols, outcomes, biomarker analysis and methodological quality were extracted by two researchers independently. Within a study, we defined the measure of the value of a biomarker in predicting efficacy or biomarker-treatment interaction as the hazard ratio in patients with the biomarker relative to that in those without the marker. The ratio of hazard ratios from relevant studies was then combined by using the random-effect model. / Heterogeneity among studies was assessed by the Cochran’ Q test and I². Sensitivity analyses were conducted to examine the impact of factors such as methodological quality on the results. Begg’s funnel plots and Egger’s tests were used to examine the possibility of publication bias. / Results: Eighteen studies were included. The number of patients available for analyses on different biomarkers varied from 1,763 to 3,246. Data on the methodological quality of included studies are generally under-reported. Some studies seemed to have important biases. EGFR TKIs are in general effective in increasing progression-free and overall survival as compared with placebo although the effect size is smaller for overall survival than for progression free survival. EGFR TKIs are comparable to chemotherapy in their effect in prolonging both progression-free and overall survival, except in EGFR mutation group in which EGFR TKIs seem much more effective than chemotherapy in prolonging progression-free survival. / Importantly, for progression-free survival, the summary ratio of hazard ratios was 0.37 (95% confidence interval [CI]: 0.22-0.60, P < 0.0001) for EGFR mutations (versus wild-type), 0.72 (95% CI: 0.52-0.99, P = 0.04) for EGFR gene copy number gain (versus no gain), 0.99 (95% CI: 0.78-1.26, P = 0.93) for EGFR protein expression (versus negative), and 1.35 (95% CI: 1.02-1.80, P = 0.04) for KRAS mutations (versus wild-type), indicating interaction may exist between EGFR TKIs and EGFR mutation, EGFR gene copy number and KRAS mutations. For overall survival, the summary ratio of hazard ratios for EGFR mutations, EGFR gene copy number gain, EGFR protein expression and KRAS mutations was 0.84 (95% CI: 0.64-1.11, P = 0.22), 0.92 (95% CI: 0.69-1.23, P = 0.57), 0.86 (95% CI: 0.70-1.05, P = 0.14) and 1.37 (95% CI: 0.89-2.10, P =0.15), respectively. / In general, the results on EGFR gene copy number gain, KRAS mutations and EGFR protein expression were less certain than those on EGFR mutations in terms of statistical significance, consistency and robustness, and the results on overall survival were less certain than those on progression-free survival. Publication bias did not seem present in the study. / Conclusions: EGFR mutations and possibly EGFR-GCN and KRAS mutations can help identify who are more likely to benefit from EGFR TKIs treatment. However, it is not clear whether the interaction with EGFR-GCN and KRAS mutations are independent or obtained through their relation with EGFR mutations. Furthermore, in EGFR wild-type patients, given that chemotherapy is cheaper and of fewer side effects, chemotherapy seems clearly a better choice than EGFR TKIs. / Our findings provided the most comprehensive evidence for the recommendations of current guidelines. Although the predictive value of the other 3 biomarkers in wild-type EGFR patients may be worth further investigation, we suggest that multivariate analyses are explored in future studies of biomarker-treatment interactions. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Yang, Zuyao. / Thesis (Ph.D.) Chinese University of Hong Kong, 2014. / Includes bibliographical references (leaves 88-104). / Abstracts also in Chinese. / Yang, Zuyao.
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Efeito do carvedilol na prevenção da cardiotoxicidade por antraciclinas: estudo randomizado, duplo-cego, placebo controlado (CECCY Trial) / Effect of carvedilol in the prevention of chemotheraphyinduced cardiotoxicity: results of a randomized, double blind, placebocontrolled trialMônica Samuel Avila Grinberg 23 November 2018 (has links)
Introdução: O tratamento quimioterápico com antraciclina está associado à cardiotoxicidade. Sua prevenção primária com o uso de beta-bloqueadores permanece controversa. O objetivo do presente estudo é avaliar o papel do carvedilol na prevenção da cardiotoxicidade relacionada ao tratamento com antraciclina. Métodos: estudo randomizado, duplo-cego, placebo controlado que incluiu 200 pacientes com câncer de mama, fração de ejeção ventricular esquerda (FEVE) preservada e uso de doxorrubicina (240 mg/m²) para receber carvedilol ou placebo até a conclusão da quimioterapia em proporção 1:1. O desfecho primário foi a redução > 10% da FEVE em seis meses. Os desfechos secundários foram o efeito do carvedilol nos marcadores de injúria miocárdica, troponina I (TnI) e peptídeo natriurético cerebral (BNP), e na disfunção diastólica. Resultados: O desfecho primário ocorreu em 14 (14,5%) pacientes do grupo carvedilol e em 13 (13,5%) do grupo placebo (p=1,0). Não houve diferença nos valores da FEVE durante o tratamento quimioterápico ou nos valores de BNP entre os grupos. Houve diferença significativa entre os grupos na distribuição dos níveis de TnI ao longo do tempo, com menor pico de TnI no grupo carvedilol (p=0,003). Além disso, houve menor incidência de disfunção diastólica no grupo carvedilol (p=0,039). Foi observada tendência para menor aumento do diâmetro diastólico do ventrículo esquerdo do início do tratamento até o final da quimioterapia no grupo carvedilol em relação ao placebo, respectivamente, 44,1+3,64 a 45,2+3,2 vs 44,9+3,6 a 46,4+4,0 mm (p=0,057). Conclusão: A incidência de cardiotoxicidade com o uso de doses contemporâneas de ANT foi menor do que relatado previamente com doses mais elevadas. Neste cenário, a administração de carvedilol resultou em redução significativa da injúria miocárdica avaliada pelos níveis de troponina I e pelo aparecimento da disfunção diastólica. No entanto, essa redução não teve impacto na disfunção sistólica relacionada à cardiotoxicidade (NCT01724450) / Background: Anthracycline (ANT) chemotherapy is associated with cardiotoxicity. Its prevention with beta-blockers remains controversial. The aim of this prospective, randomized, double-blind, placebo-controlled study was to evaluate the role of carvedilol in the prevention of early onset ANT cardiotoxicity. Methods: We randomized 200 patients with breast cancer and normal left ventricular ejection fraction (LVEF) referred for doxorubicin (240 mg/m²) to receive carvedilol or placebo until completion of chemotherapy. The primary end-point was a reduction > 10% in LVEF at six months. Secondary outcomes were the effects of carvedilol on troponin I (TnI), BNP and diastolic dysfunction. Results: Primary end-point occurred in 14 (14.5%) patients in the carvedilol and in 13 (13.5%) in the placebo (p=1.0). No difference in changes of LVEF or BNP was noted between groups. There was a significant difference between groups on the TnI levels over time, with lower TnI levels in carvedilol group (p=0.003). Additionally, a lower incidence of diastolic dysfunction was seen in carvedilol group (p=0.039). A trend towards less pronounced increase in LV end-diastolic diameter during follow up was noted in the carvedilol group, respectively 44.1+3.64 to 45.2+3.2 vs 44.9+3.6 to 46.4+4.0 mm (p=0.057). Conclusion: In this largest clinical trial of ?-blockers for prevention of early onset cardiotoxicity under contemporary doses of ANT, we noted a lower incidence of cardiotoxicity than higher doses. In this scenario, the use of carvedilol resulted in a significant reduction in troponin levels and diastolic dysfunction. However, this reduction had no impact on the incidence of cardiotoxicity-related myocardial systolic dysfunction (NCT01724450)
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JMJD3 acts as a tumor suppressor by disrupting cytoskeleton in pancreatic ductal adenocarcinoma cells. / CUHK electronic theses & dissertations collectionJanuary 2013 (has links)
Xiao, Zhangang. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2013. / Includes bibliographical references (leaves 118-131). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts also in Chinese.
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Functional characterization of molecular determinants (endothelial nitric oxide synthase/eNOS and nuclear receptor TLX) in castration- and antiandrogen-resistant growth of prostate cancer. / 內皮細胞型一氧化氮合成酶(eNOS)和核受體TLX在去勢難治性和抗雄激素耐受性前列腺癌中的功能研究 / CUHK electronic theses & dissertations collection / Nei pi xi bao xing yi yang hua dan he cheng mei (eNOS) he he shou ti TLX zai qu shi nan zhi xing he kang xiong ji su nai shou xing qian lie xian ai zhong de gong neng yan jiuJanuary 2013 (has links)
Jia, Lin. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2013. / Includes bibliographical references (leaves 124-146). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.
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Modulation of Dopaminergic System Ontogeny by Low-Level Lead Exposure: A Potential Underlying Mechanism for the Onset of Drug SensitizationSoares, Barbara Domingos January 2016 (has links)
Lead (Pb²⁺) is an environmental toxin that is known to cause lasting cognitive deficits following early life exposure. Previously, our laboratory demonstrated increased sensitivity to the psychostimulant effects of cocaine in animals with elevated blood Pb²⁺ levels (BLL). This effect was abolished following introduction of dopamine (DA) receptor antagonists, indicating that the dopaminergic (DAergic) system may be a target of Pb²⁺’s toxic effects. However, the biological mechanisms through which Pb²⁺ increased sensitization to cocaine’s psychostimulant effects have not been fully elucidated. There is some disagreement regarding the magnitude and direction of Pb²⁺’s effects on the DAergic system. Furthermore, many studies to date have measured the effects of Pb²⁺ in only one sex (usually male), one exposure, and one or two time-points, making it difficult to determine any potential sex-, age-, and exposure-dependent effects.
In the present study, we used a well-validated animal model and Pb²⁺ exposure paradigm that uses chronic dietary exposure to 180ppm and 1500ppm Pb²⁺ acetate (PbAC) in the diet. These levels of Pb²+ in the diet resulted in low and moderate levels of BLLs that on average approximated 4.5 and 22.0µg/dl in young adult rats. These levels of Pb²⁺ exposure are relevant to contemporary levels of BLL in intoxicated children in many cities in the United States and in many parts of the world where Pb²⁺ exposure continues to be a major public health concern. It should be noted that at the low level of Pb²⁺ exposure, the resulting BLL of 4.5µg/dl is just below the current CDC level of action.
Using this well-defined rat model of chronic Pb²⁺ exposure, in Aim 1, we measured DA concentration and turnover in the dorsal striatum (STR) of juvenile (PN14), adolescent (PN28), and young adult (PN50) male and female rats. Tyrosine hydroxylase (TH) protein, the rate-limiting step in the synthesis of DA, and phosphorylation of TH at serine 40 (pser40TH) were assessed as an indirect measure of TH activity. Thus, we measured the ratio of pser40TH to total TH protein. We also measured vesicular monoamine transporter-type 2 (VMAT2) levels in the STR, nucleus accumbens (NAC), and olfactory tubercle (OT) since this protein is critical for the sequestration of DA in presynaptic vesicles and has been used as a biomarker for DA terminal integrity. In Aim 2, we examine the effect of chronic Pb²⁺ exposure on D1 and D2 dopamine receptor (D1R and D2R) in the OT, NAC, and STR. Analysis of D1R and D2R is important since the downstream effects of DA are dependent on the DA receptor subtype it activates.
In Aim 1, we observed significant increases in DA and its metabolites homovanillic acid (HVA) and 3,4-Dihydroxyphenylacetic acid (DOPAC) in the STR of adolescent and young adult male rats with BLL as low as 4.5µg/dl in the absence of phosphorylation at the serine 40 residue of TH or altered VMAT2 levels. In Aim 2, a significant increase in D2R was detected in the juvenile male rat STR. We also observed increases in D1R expression in adolescent male rats in the NAC, OT, STR, and in the OT of adolescent female rats. Together, these results demonstrate that chronic Pb²⁺ exposure alters DA receptor levels in a manner characteristic of a hyperactive DAergic state. The observations presented in this work suggest that a hyperactive DAergic system underlies the heightened sensitization to cocaine we previously observed in Pb²⁺-exposed animals. This work builds upon the current understanding of how Pb²⁺ modulates the DAergic system and provides some elucidation of the mechanisms underlying increased drug sensitization our laboratory has previously observed in rats exposed to Pb²⁺.
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Efeito da tansulosina e do nifedipino na eliminação de fragmentos após litotripsia extracorpórea por ondas de choque em pacientes com cálculos renais: estudo prospectivo, duplo-cego e randomizado / Effect of tamsulosin and nifedipine on the clearance of fragments after extracorporeal shock waves lithotripsy in patients with kidney stones - a prospective, double-blind and randomized studyVicentini, Fabio Carvalho 18 March 2011 (has links)
Introdução: A litotripsia extracorpórea por ondas de choque (LEOC) é o tratamento mais utilizado para cálculos renais de até 20 mm. O uso adjuvante de algumas drogas pode aumentar as taxas de sucesso do procedimento e diminuir a sua morbidade. Objetivos: Avaliar os efeitos da tansulosina e do nifedipino nas taxas de sucesso, nos episódios de dor e na velocidade de eliminação dos fragmentos após o tratamento de cálculos renais de 5 a 20 mm com uma única sessão de LEOC. Casuística e Métodos: Foram estudados prospectivamente 136 indivíduos portadores de cálculos renais entre 5 e 20 mm, submetidos à LEOC entre 2006 e 2009. Os pacientes foram divididos aleatoriamente em 3 grupos para receber diariamente tansulosina 0,4 mg, nifedipino retard 20mg ou placebo por até 30 dias da realização de LEOC. A analgesia foi feita com celecoxibe 200 mg. Os pacientes foram avaliados semanalmente por meio de radiografia de abdome. Foi definido como sucesso do tratamento a ausência de fragmentos maiores que 4 mm ao final de 30 dias. Os parâmetros avaliados foram: taxa de sucesso do tratamento, ocorrência de rua de cálculos, necessidade de analgésicos, intensidade de dor após a LEOC, tempo de eliminação de fragmentos, efeitos adversos da medicação e visitas ao Pronto Socorro. Resultados: Cento e onze pacientes completaram o estudo. Não houve diferenças demográficas entre os pacientes e nem em relação ao tamanho dos cálculos entre os grupos. As taxas de sucesso foram de 60,5% (23 de 38) no Grupo Tansulosina, 48,6% (17 de 35) no Grupo Nifedipino e 36,8% (14 de 38) no Grupo Placebo. (p=0,118) Entre os pacientes com cálculos de 10 a 20 mm, a taxa de sucesso foi significativamente maior nos Grupos Tansulosina (61,9%) e Nifedipino (60,0%) do que no Grupo Placebo (26,1%) (p=0,024), porém não foi significativa entre os cálculos de 5 a 9 mm (p=0,128). O Número Necessário para Tratar (NNT) da Tansulosina foi de 2,9 e o do Nifedipino foi de 3, considerando-se o uso para cálculos de 10 a 20 mm. Os pacientes que usaram nifedipino tiveram mais efeitos adversos do que os do Grupo Placebo (28,5 % x 2,6% respectivamente, p = 0,009), porém sem levar à interrupção do uso da drogas. Não houve diferença significativa entre os grupos Tansulosina x Nifedipino e Tansulosina x Placebo em relação aos efeitos adversos (p= 0,15 e p = 0,054, respectivamente). Não houve diferença entre os grupos com relação à intensidade da dor observada após o tratamento (p=0,28), ao número de comprimidos de Celecoxibe (p=0,39), ao tempo de eliminação dos fragmentos (p=0,6), à ocorrência de rua de cálculos (p=0,482) e ao número de vistas ao Pronto Socorro (p=0,175). Conclusões: O uso adjuvante de tansulosina ou de nifedipino após LEOC aumenta a taxa de sucesso para cálculos renais entre 10 e 20 mm, porém sem diminuir a intensidade da dor ou a necessidade de analgésicos após o tratamento, nem o tempo de eliminação dos fragmentos / Purpose: We evaluated the effects of the adjuvant use of tamsulosin and nifedipine after extracorporeal shock wave lithotripsy (SWL) for 5-20 mm kidney stones. Materials and Methods: We conducted a randomized double-blind trial involving 136 patients with radiopaque kidney stones between 2006 and 2009. Patients were divided into three groups to receive daily treatments of 0.4 mg tamsulosin, 20 mg nifedipine retard or placebo for up to 30 days after one session of SWL. The parameters assessed were success rate, analgesic requirements, pain intensity, time to clearance, adverse effects and occurrence of Steinstrasse. Results: The success rate was 60.5% (23 of 38) in the Tamsulosin group, 48.6% (17 of 35) in the Nifedipine group and 36.8% (14 of 38) in the Placebo group (p=0.118). For stones ranging from 10 to 20 mm, the success rates were significantly higher in the Tamsulosin (61.9%) and Nifedipine groups (60.0%) when compared with the Placebo group (26.1%) (p=0.024), but not for the 5-9 mm stones (p=0.128). The Number Needed to Treat was 2.9 for tamsulosin and 3 for nifedipine. Adverse events were more frequent in the Nifedipine than the Placebo Group (28.5% vs. 2.6%, respectively, p=0.009). There was no difference among groups with regard to stone and demographic characteristics, pain intensity, time to clearance and Steinstrasse. Conclusions: Adjuvant use of tamsulosin or nifedipine after SWL significantly increased the success rates for 10 to 20 mm renal stones and could be recommended. Both drugs had similar beneficial effects and adverse events
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Role of 5-HT₃ and tachykinin NK₁ receptors in drug-induced emesis and associated behaviours in the ferret and suncus murinus.January 2003 (has links)
Lau Hoi Yan. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2003. / Includes bibliographical references (leaves 134-157). / Abstracts in English and Chinese. / PUBLICATIONS BASED ON WORK IN THIS THESIS --- p.I / ABSTRACT --- p.II / ACKNOWLEDGEMENTS --- p.VI / TABLE OF CONTENTS --- p.VIII / Chapter CHAPTER 1 --- INTRODUCTION --- p.1 / Chapter 1.1 --- General Introduction --- p.1 / Chapter 1.2 --- Emesis --- p.3 / Chapter 1.2.1 --- Introduction --- p.3 / Chapter 1.2.2 --- Retching & Vomiting --- p.3 / Chapter 1.2.3 --- Nausea --- p.4 / Chapter 1.2.4 --- Motor Components of Emetic Reflex --- p.5 / Chapter 1.2.4.1 --- Pre-ejection Phase --- p.5 / Chapter 1.2.4.2 --- Ejection Phase --- p.5 / Chapter 1.2.4.3 --- Post-ejection Phase --- p.6 / Chapter 1.2.5 --- Components of Emetic Reflex --- p.6 / Chapter 1.2.5.1 --- Area Postrema (AP) --- p.6 / Chapter 1.2.5.2 --- Nucleus Tractus Solitarius (NTS) --- p.7 / Chapter 1.2.5.3 --- Vomiting Centre --- p.8 / Chapter 1.2.5.4 --- Vestibular System --- p.10 / Chapter 1.2.5.5 --- Abdominal Visceral Afferents --- p.10 / Chapter 1.2.5.6 --- Forebrain --- p.11 / Chapter 1.2.6 --- Neurotransmitters & Receptors --- p.12 / Chapter 1.2.7 --- Anti-emetics --- p.13 / Chapter 1.3 --- Models of Nausea --- p.16 / Chapter 1.3.1 --- Introduction --- p.16 / Chapter 1.3.2 --- Conditioned Taste Aversion --- p.18 / Chapter 1.3.3 --- Pica Behaviour --- p.20 / Chapter 1.3.4 --- Studies of the Involvement of Vasopressin --- p.21 / Chapter 1.3.5 --- Tachygastria --- p.24 / Chapter 1.3.6 --- Locomotor Activity --- p.26 / Chapter 1.4 --- Markers of Neuronal Activity --- p.27 / Chapter 1.4.1 --- General Comments --- p.27 / Chapter 1.4.2 --- c-fos Expression as a Marker of Neuronal Activity --- p.28 / Chapter 1.4.2.1 --- What is c-fos? --- p.28 / Chapter 1.4.2.2 --- Regulation of c-fos Expression --- p.30 / Chapter 1.4.2.2.1 --- Calcium Response Element --- p.31 / Chapter 1.4.2.2.2 --- Serum Response Element --- p.32 / Chapter 1.4.2.3 --- Types of Receptors Involved in c-fos Expression --- p.32 / Chapter 1.4.2.4 --- Feasibility of Using c-fos Expression as Marker of Cellular Activity --- p.36 / Chapter 1.4.2.5 --- Identification of Emetic Pathway by c-fos Immunohistochemistry --- p.36 / Chapter 1.5 --- Aims & Objectives --- p.37 / Chapter CHAPTER 2 --- METHODS --- p.42 / Chapter 2.1 --- Animals --- p.42 / Chapter 2.1.1 --- Ferrets --- p.42 / Chapter 2.1.2 --- Suncus murinus --- p.42 / Chapter 2.2 --- Measurement of Animal Behaviour --- p.43 / Chapter 2.2.1 --- Experiment Design --- p.43 / Chapter 2.2.2 --- Recording of Animal Behaviour --- p.43 / Chapter 2.2.3 --- Calibration of Equipment Used to Record Spontaneous Locomotor Activity --- p.44 / Chapter 2.2.4 --- Behaviour Recorded by the Observer --- p.45 / Chapter 2.3 --- Administration of Drugs --- p.46 / Chapter 2.3.1 --- Ferrets --- p.46 / Chapter 2.3.1.1 --- General Comments --- p.46 / Chapter 2.3.1.2 --- Drug Antagonism Studies --- p.47 / Chapter 2.3.2 --- Suncus murinus --- p.47 / Chapter 2.3.2.1 --- General Comments --- p.47 / Chapter 2.3.2.2 --- Dose-Response Studies --- p.48 / Chapter 2.3.2.3 --- Drug Antagonism Studies --- p.48 / Chapter 2.4 --- c-fos Expression Studies in Ferret Brainstems --- p.50 / Chapter 2.4.1 --- Animals and Anaesthesia --- p.50 / Chapter 2.4.2 --- Perfusion and fixation --- p.50 / Chapter 2.4.3 --- Dehydration of brains --- p.51 / Chapter 2.4.4 --- Embedding of tissue --- p.52 / Chapter 2.4.5 --- Sectioning --- p.52 / Chapter 2.4.6 --- Staining --- p.52 / Chapter 2.4.7 --- Antibodies used --- p.55 / Chapter 2.4.8 --- Positive Control Slides --- p.55 / Chapter 2.5 --- Experimental Design and Statistics --- p.56 / Chapter 2.5.1 --- Randomization of Treatments --- p.56 / Chapter 2.5.2 --- Statistics --- p.57 / Chapter 2.5.2.1 --- Ferrets --- p.57 / Chapter 2.5.2.2 --- Suncus murinus --- p.59 / Chapter 2.6 --- Drugs and Chemicals Used --- p.60 / Chapter 2.6.1 --- Drugs Used --- p.60 / Chapter 2.6.2 --- Chemicals Used --- p.62 / Chapter CHAPTER 3 --- RESULTS --- p.63 / Chapter 3.1 --- Ferret --- p.63 / Chapter 3.1.1 --- "The Effect of Ondansetron and CP-99,994 on Emesis and Locomotor Activity Changes Induced by Cisplatin in the Ferret" --- p.63 / Chapter 3.1.2 --- The Effect of Domperidone on Emesis and Locomotor Activity Changes Induced by Apomorphine in the Ferret --- p.69 / Chapter 3.1.3 --- "The Effect of CP-99,994 on Emesis and Locomotor Activity Changes Induced by Apomorphine in the Ferret" --- p.74 / Chapter 3.1.4 --- c-fos Expression Studies in Ferret Brainstems --- p.79 / Chapter 3.1.4.1 --- Cisplatin-treated Ferrets --- p.79 / Chapter 3.1.4.2 --- Positive Control Slides --- p.84 / Chapter 3.2 --- Suncus murinus --- p.88 / Chapter 3.2.1 --- The Emetic Potential of Nicotine and its Effects on the Spontaneous Locomotor Activity of Suncus murinus --- p.88 / Chapter 3.2.2 --- "The Effect of CP-99,994 on Emesis and Locomotor Activity Changes Induced by Nicotine in Suncus murinus" --- p.92 / Chapter 3.2.3 --- The Emetic Potential of Copper Sulphate and its Effects on the Spontaneous Locomotor Activity of Suncus murinus --- p.95 / Chapter 3.2.4 --- "The Effect of CP-99,994 on Emesis and Locomotor Activity Changes Induced by Copper Sulphate in Suncus murinus" --- p.98 / Chapter 3.2.5 --- The Emetic Potential of Cisplatin and its Effects on the Spontaneous Locomotor Activity of Suncus murinus --- p.101 / Chapter 3.2.6 --- The Effect of Ondansetron on Emesis and Locomotor Activity Changes Induced by Cisplatin in Suncus murinus --- p.104 / Chapter 3.2.7 --- "The Effect of CP-99,994 on Emesis and Locomotor Activity Changes Induced by Cisplatin in Suncus murinus" --- p.107 / Chapter 3.2.8 --- "The Effects of Ondansetron and CP-99,994 on Locomotor Activity in Suncus murinus" --- p.110 / Chapter CHAPTER 4 --- DISCUSSION --- p.113 / Chapter CHAPTER 5 --- GENERAL SUMMARY --- p.130 / REFERENCES --- p.134
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