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子宫外环境下新生儿发育的对比增强脑超声灌注指标 (EXTEND): 与血流动力学参数的相关性。
OBJECTIVES:Contrast-enhanced ultrasound (CEUS) can provide quantitative perfusion metrics and may be useful to detect cerebral pathology in neonates and premature infants, particularly in extrauterine environments. The effect of hemodynamics on cerebral perfusion metrics is unknown, which limits the clinical application of this technology. We aimed to determine associations between systemic hemodynamics and concurrently measured brain perfusion parameters in an animal model of extrauterine support. METHODS:Nine fetal lambs were transferred to an extrauterine support device. Lumason® ultrasound contrast (0.1-0.3 ml) was administered via the umbilical vein and 90-second cine clips were obtained. Time-intensity-curves (TICs) were generated and time-dependent and area-under-curve (AUC) parameters were derived. Associations between brain perfusion metrics and hemodynamics including heart rate (HR) and mean arterial pressure (MAP) were evaluated by multilevel linear mixed-effects models. RESULTS:Eighty-six ultrasound examinations were performed and 72 examinations were quantifiable. Time-dependent measurements were independent of all hemodynamic parameters (all p ≥.05). Oxygen delivery and mean blood flow were correlated with AUC measurements (all p ≤.01). Physiologic HR and MAP were not correlated with any measurements (all p ≥.05). CONCLUSION:Detected aberrations in time-dependent CEUS measurements are not correlated with hemodynamic parameters and are thought to reflect the changes in cerebral blood flow, thus providing a promising tool for evaluation of brain perfusion. CEUS brain perfusion parameters are not correlated with physiologic HR and MAP, but AUC-dependent measurements are correlated with oxygen delivery and blood flow, suggesting that CEUS offers additional value over standard monitoring. Overall, these findings enhance the applicability of this technology.
目的: 超声造影 (CEUS) 可以提供定量灌注指标,并可能有助于检测新生儿和早产儿的脑部病理,特别是在宫外环境中。血流动力学对脑灌注指标的影响尚不清楚,限制了该技术的临床应用。我们的目的是在宫外支持动物模型中确定全身血流动力学和同时测量的脑灌注参数之间的关联。 方法: 将9只胎儿羔羊转移至宫外支持装置。Lumason®经由脐静脉施用超声造影剂 (0.1-0.3 ml),并获得90秒电影剪辑。生成时间-强度-曲线 (tic) 并导出时间依赖性和曲线下面积 (AUC) 参数。通过多水平线性混合效应模型评估脑灌注指标与包括心率 (HR) 和平均动脉压 (MAP) 在内的血流动力学之间的关联。 结果: 共行超声检查86例,可量化检查72例。时间依赖性测量独立于所有血流动力学参数 (均p ≥.05)。氧输送和平均血流量与AUC测量值相关 (所有p ≤.01)。生理HR和MAP与任何测量值均不相关 (均p ≥.05)。 结论: 时间依赖性CEUS测量中检测到的像差与血流动力学参数不相关,被认为反映了脑血流的变化,从而为评价脑灌注提供了一个有前途的工具。CEUS脑灌注参数与生理HR和MAP不相关,但AUC依赖性测量与氧递送和血流量相关,表明CEUS提供了超过标准监测的附加值。总体而言,这些发现增强了该技术的适用性。
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METHODS::The ATP binding-cassette superfamily corresponds the mostly transmembrane transporters family found in humans. These proteins actively transport endogenous and exogenous substrates through biological membranes in body tissues, so they have an important role in the regulation of many physiological functions necessary for human homeostasis, as well as in response regulation to several pharmacological substrates. The development of multidrug resistance has become one of the main troubles in conventional chemotherapy in different illnesses including cancer, being the increased efflux of antineoplastic drugs the main reason for this multidrug resistance, with a key role of the ABC superfamily. Likely, the interindividual variability in the pharmacological response among patients is well known, and may be due to intrinsically factors of the disease, genetic and environmental ones. Thus, the understanding of this variability, especially the genetic variability associated with the efficacy and toxicity of drugs, can provide a safer and more effective pharmacological treatment, so ABC genes are considered as important regulators due to their relationship with the reduction in pharmacological response. In this review, updated information about transporters belonging to this superfamily was collected, the possible role of these transporters in cancer, the role of genetic variability in their genes, as well as some therapeutic tools that have been tried to raise against main transporters associated with chemoresistance in cancer.
METHODS:BACKGROUND:Cholinergic neurotransmission regulates neuroinflammation in Parkinson disease (PD). RESEARCH DESIGN AND METHODS:The authors conducted a delayed-start study of donepezil for cognitive decline in non-demented PD patients. The study consisted of a 96-week randomized placebo-controlled double-blind phase 1, followed by a 24-week donepezil extension phase 2. The primary outcome measure was a change in the Mini-Mental State Examination (MMSE) at week 120. RESULTS:A total of 98 patients were randomly allocated to the early-start (donepezil-to-donepezil) and delayed-start (placebo-to-donepezil) groups. Mean (SD) of the baseline MMSE was 27.6 (2.0) and 28.0 (2.1), respectively. MMSE change at week 120 was better in the early-start group than in the delayed-start group, but the difference was not significant. The MMSE declined in apolipoprotein ε4 carriers, but not in non-carriers, and the factor interaction (intervention × ε4 genotype) was highly significant (P < 0.001). Analyzed with the interaction, the difference was significant (group difference 1.95 [0.33 to 3.57], P = 0.018). The MMSE decline slope in phase 1 was significantly better in the early-start group than in the delayed-start group (P = 0.048). CONCLUSIONS:Cognitive function deteriorated in ε4 carriers, but not in non-carriers, and early-start donepezil may postpone cognitive decline in the former.
METHODS::Since the discovery of dental pulp stem cells, a lot of teams have expressed an interest in dental pulp regeneration. Many approaches, experimental models and biological explorations have been developed, each including the use of stem cells and scaffolds with the final goal being clinical application in humans. In this review, the authors' objective was to compare the experimental models and strategies used for the development of biomaterials for tissue engineering of dental pulp with stem cells. Electronic queries were conducted on PubMed using the following terms: pulp regeneration, scaffold, stem cells, tissue engineering and biomaterial. The extracted data included the following information: the strategy envisaged, the type of stem cells, the experimental models, the exploration or analysis methods, the cytotoxicity or viability or proliferation cellular tests, the tests of scaffold antibacterial properties and take into account the vascularization of the regenerated dental pulp. From the 71 selected articles, 59% focused on the "cell-transplantation" strategy, 82% used in vitro experimentation, 58% in vivo animal models and only one described an in vivo in situ human clinical study. 87% used dental pulp stem cells. A majority of the studies reported histology (75%) and immunohistochemistry explorations (66%). 73% mentioned the use of cytotoxicity, proliferation or viability tests. 48% took vascularization into account but only 6% studied the antibacterial properties of the scaffolds. This article gives an overview of the methods used to regenerate dental pulp from stem cells and should help researchers create the best development strategies for research in this field.
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