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Objective: Animal environments for the growth of stem cells cause the transmission of some diseases and immune problems for the recipient. Accordingly, replacing these environments with healthy environments, at least with human resources, is essential.  One of the media that can be used as an alternative to animal serums is Wharton acellular jelly (AWJ).  Therefore, in this study, we intend to replace FBS with Wharton jelly and investigate its effect on the expression of megakaryocyte-related genes and markers in stem cells. Materials and Methods: In this study, cord blood-derived CD34 positive HSCs were cultured and expanded in the presence of cytokines including SCF, TPO, and FLT3-L. Then, the culture of expanded CD34 positive HSCs was performed in two groups: 1) IMDM culture medium containing 10% FBS and 100 ng / ml thrombopoietin cytokine 2) IMDM culture medium containing 10% AWJ, 100 ng / ml thrombopoietin cytokine.  Finally, CD41 expressing cells were analyzed with the flow cytometry method. The genes related to megakaryocyte lineage including FLI1 and GATA2 were also evaluated using the RT-PCR technique.  Results: The expression of CD41, a specific marker of megakaryocyte lineage in culture medium containing Wharton acellular jelly was increased compared to the FBS group. Additionally, the expression of GATA2 and FLI1 genes was significantly increased related to the control group. Conclusion: This study provided evidence of differentiation of CD34 positive hematopoietic stem cells from umbilical cord blood to megakaryocytes in a culture medium containing AWJ.  相似文献   
3.
AimsThis review aims to provide an update of available methods for imaging calcification activity and potential therapeutic options.Data SynthesisAortic valve calcification represents the most common heart valve condition requiring treatment among adults in Western societies. No medical therapies are proven to be effective in treating symptoms or reducing disease progression. Therefore, surgical or transcatheter aortic valve replacement remains the only available treatment option. Elevated circulating concentrations of lipoprotein(a) is strongly associated with degenerative aortic stenosis. This relationship was first observed in prospective observational studies, and the causal relationship was confirmed in genetic studies.ConclusionsNew therapeutic targets have been identified and new imaging techniques could be used to test the effectiveness of new agents and further clarify the pathophysiology of AVS. No therapy that specifically lowers Lp (a) levels has been approved for clinical use.  相似文献   
4.
目的 探究MicroRNA-4516(miR-4516)、MicroRNA-198(miR-198)在视网膜母细胞瘤(RB)Y79细胞中的表达及其临床意义。方法 收集2018年3月至2021年3月行眼球摘除术治疗的35例RB患儿的肿瘤组织及30例正常视网膜组织标本,比较肿瘤组织、正常视网膜组织和Y79细胞中miR-4516、miR-198的表达水平。脂质体转染法建立miR-4516、miR-198过表达组(miR-4516-mimics组、miR-198-mimics组)、抑制组(miR-4516-inhibitor组、miR-198-inhibitor组)和对照组(miR-4516-NC组、miR-198-NC组)。CCK-8法检测转染24 h、48 h和72 h后各组细胞的增殖活性;实时荧光定量PCR(qRT-PCR)法检测转染48 h后各组细胞miR-4516、miR-198表达水平;流式细胞术检测各组细胞凋亡率;Western blot法检测各组细胞P53、Bcl-2蛋白表达。结果 肿瘤组织及Y79细胞中miR-4516的表达水平均高于正常视网膜组织,miR-198则相反,差异均有统计学意义(均为P<0.05)。细胞转染48 h后,miR-4516、miR-198分别在各自的inhibitor组、NC组和mimics组细胞内相对表达量逐渐升高(均为P<0.05)。转染后24 h、48 h、72 h,各组细胞增殖活性均逐渐升高,差异均有统计学意义(均为P<0.05),且同一时间点各组的细胞增殖活性比较,miR-4516-mimics组>miR-4516-NC组>miR-4516-inhibitor组,miR-198-inhibitor组>miR-198-NC组>miR-198-mimics组,差异均有统计学意义(均为P<0.05)。转染后48 h,各组细胞凋亡率比较,miR-4516-inhibitor组>miR-4516-NC组>miR-4516-mimics组,miR-198-mimics组>miR-198-NC组>miR-198-inhibitor组,差异均有统计学意义(均为P<0.05)。P53蛋白在miR-4516-mimics组、miR-4516-NC组和miR-4516-inhibitor组中表达逐渐升高,Bcl-2蛋白表达逐渐降低,差异均有统计学意义(均为P<0.05);P53蛋白在miR-198-mimics组、miR-198-NC组、miR-198-inhibitor组中表达逐渐降低,Bcl-2蛋白表达逐渐升高,差异均有统计学意义(均为P<0.05)。结论 miR-4516在RB肿瘤组织及Y79细胞中呈高表达状态,miR-198呈低表达状态;miR-4516可促进Y79细胞增殖,抑制其凋亡,miR-198可抑制Y79细胞增殖,二者有望成为RB的新的肿瘤标志物。  相似文献   
5.
Introduction and objectivesThe index of microcirculatory resistance (IMR) measured after primary percutaneous coronary intervention (PCI) for ST-segment elevation myocardial infarction (STEMI) is associated with microvascular obstruction (MVO) and adverse clinical events. To evaluate MVO after successful primary PCI for STEMI without pressure wires or hyperemic agents, we investigated the feasibility and usefulness of functional angiography-derived IMR (angio-IMR).MethodsThe current study included a total of 285 STEMI patients who underwent primary PCI and cardiac magnetic resonance (CMR). Angio-IMR of the culprit vessel after successful primary PCI was calculated using commercial software. MVO, infarct size, and myocardial salvage index were assessed using CMR, which was obtained a median of 3.0 days [interquartile range, 3.0-5.0] after primary PCI.ResultsAmong the total population, 154 patients (54.0%) showed elevated angio-IMR (> 40 U) in the culprit vessel. MVO was significantly more prevalent in patients with angio-IMR > 40 U than in those with angio-IMR ≤ 40 U (88.3% vs 32.1%, P < .001). Infarct size, extent of MVO, and area at risk were significantly larger in patients with angio-IMR > 40 U than in those with angio-IMR ≤ 40 U (P < .001 for all). Angio-IMR showed a significantly higher discriminatory ability for the presence of MVO than thrombolysis in myocardial infarction flow grade or myocardial blush grade (area under the curve: 0.821, 0.504, and 0.496, respectively, P < .001).ConclusionsAngio-IMR was significantly associated with CMR-derived infarct size, extent of MVO, and area at risk. An elevated angio-IMR (> 40 U) after primary PCI for STEMI was highly predictive of the presence of MVO in CMR.This trial was registered at ClnicalTrialsgov (Identifier: NCT04828681).  相似文献   
6.
In this fifth phase of development, the contents of the Spanish Asthma Management Guidelines (GEMA), which include versions 5.0 and 5.1, have undergone a thorough review. The aim here is to set the main changes in context. These could be summarized as follows: DIAGNOSIS: new FENO cut-off and severity classification based on treatment needed to maintain control; INTERMITTENT ASTHMA: a more restrictive concept and treatment extended to include a glucocorticoid/adrenergic combination as needed; MILD ASTHMA: glucocorticoid/adrenergic therapy as needed as an alternative in case of low therapeutic adherence to conventional fixed-dose steroids; SEVERE ASTHMA: readjustment of phenotypes, incorporation of triple therapy in a single inhaler, and criteria for selection of a biologic in severe uncontrolled asthma; OTHERS: specific scoring in childhood asthma, incorporation of certain organizational aspects (care circuits, asthma units, telemedicine), new sections on COVID-19 and nasal polyposis.  相似文献   
7.
目的分析血清微小核糖核酸(miR)-133a在脓毒症并发急性呼吸窘迫综合征(acute respiratory distress syndrome, ARDS)患者中的表达及与预后的关系。 方法选取2019年6月至2021年5月我院收治的65例脓毒症患者,根据是否并发ARDS,分为并发ARDS 35例和无ARDS 30例。随访28 d,统计脓毒症并发ARDS者预后,检测患者入住ICU第1天、第2天、第3天血清miR-133a水平,比较存活者和死亡者临床特征,采用Logistic回归分析判定影响脓毒症并发ARDS预后的因素,采用受试者工作曲线(ROC)分析血清miR-133a水平预测脓毒症并发ARDS者预后的价值。 结果并发ARDS入住ICU第1天、第2天、第3天血清miR-133a水平均高于无ARDS者(P<0.05);随访28 d,脓毒症并发ARDS者病死率为40.00%;死亡者入住ICU第1天、第2天、第3天血清miR-133a水平均高于存活者(P<0.05);死亡者序贯器官衰竭(SOFA)评分、血管外肺水指数、第1天血清miR-133a水平与存活者比较,差异均有统计学意义(P<0.05);Logistic多因素回归分析显示SOFA评分、第1天血清miR-133a水平均是影响脓毒症并发ARDS者死亡的危险因素(P<0.05);ROC分析显示,第1天血清miR-133a水平预测脓毒症并发ARDS者死亡的最佳截断点为1.47,灵敏度为85.71%,特异度为90.48%,AUC为0.857。 结论脓毒症并发ARDS者血清miR-133a水平升高,血清miR-133a水平是影响脓毒症并发ARDS者死亡的危险因素,监测血清miR-133a水平变化,作为预测患者预后的指标。  相似文献   
8.
Cadmium is a toxic metal that can damage the brain and other organs. This study aimed to explore the protective effects of Potentilla anserine L. polysaccharide (PAP) against CdCl2-induced neurotoxicity in N2a and SH-SY5Y cells and in the cerebral cortex of BALB/c mice. In addition, we aimed to identify the potential mechanisms underlying these protective effects. Relative to CdCl2 treatment alone, pretreatment with PAP prevented the reduction in cell viability evoked by CdCl2, decreased rates of apoptosis, promoted calcium homeostasis, decreased ROS accumulation, increased mitochondrial membrane potential, inhibited cytochrome C and AIF release, and prevented the cleavage of caspase-3 and PARP. In addition, PAP significantly decreased the CdCl2-induced phosphorylation of CaMKII, Akt, and mTOR. In conclusion, PAP represents a potential therapeutic agent for the treatment of Cd-induced neurotoxicity, functioning in part via attenuating the activation of the mitochondrial apoptosis pathway and the Ca2+-CaMKII-dependent Akt/mTOR pathway.  相似文献   
9.
《Drug discovery today》2022,27(4):1108-1114
This project demonstrates the use of the IEEE 2791–2020 Standard (BioCompute Objects [BCO]) to enable the complete and concise communication of results from next generation sequencing (NGS) analysis. One arm of a clinical trial was replicated using synthetically generated data made to resemble real biological data and then two independent analyses were performed. The first simulated a pharmaceutical regulatory submission to the US Food and Drug Administration (FDA) including analysis of results and a BCO. The second simulated an FDA review that included an independent analysis of the submitted data. Of the 118 simulated patient samples generated, 117 (99.15%) were in agreement in the two analyses. This process exemplifies how a template BCO (tBCO), including a verification kit, facilitates transparency and reproducibility, thereby reinforcing confidence in the regulatory submission process.  相似文献   
10.
《Drug discovery today》2022,27(6):1733-1742
Compounds that exhibit assay interference or undesirable mechanisms of bioactivity are routinely encountered in assays at various stages of drug discovery. We observed that assays for the investigation of thiol-reactive and redox-active compounds have not been collected in a comprehensive review. Here, we review these assays and subject them to experimental optimization to improve their reliability. We demonstrate the usefulness of our assay cascade by assaying a library of bioactive compounds, chemical probes, and a set of approved drugs. These high-throughput assays should complement the array of wet-lab and in silico assays during the initial stages of hit discovery campaigns to pursue only hit compounds with tractable mechanisms of action.  相似文献   
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