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1.
Effect of Replacement of Wharton Acellular Jelly With FBS on the Expression of Megakaryocyte Linear Markers in Hematopoietic Stem Cells CD34+ 下载免费PDF全文
zahra Jalili Behnam Emamgolizadeh Hossein Abbaszadeh Shahla JaliliMehdi Derakhshani Mehdi YousefiMehdi TalebiKarim Shams Asenjan Ali Akabr Movassaghpour 《Asian Pacific journal of cancer prevention》2022,23(10):3281-3286
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
2.
Rupa Narayan MD Traci M. Blonquist MS Ashkan Emadi MD PhD Robert P. Hasserjian MD Meghan Burke BS Christopher Lescinskas BS Donna S. Neuberg ScD Andrew M. Brunner MD Gabriela Hobbs MD Hanno Hock MD PhD Steven L. McAfee MD Yi-Bin Chen MD Eyal Attar MD Timothy A. Graubert MD Christina Bertoli MSN Jenna A. Moran MSN Meghan K. Bergeron MSN Julia E. Foster MSN Aura Y. Ramos BSN Tina T. Som BSN Megan K. Vartanian BSN RN Jennifer L. Story LPN Kristin McGregor MS Molly Macrae BS Tanya Behnan BS Margaret C. Wey PhD Jessica Rae BSN Frederic I. Preffer PhD Patricia Lesho BA Vu H. Duong MD Mason L. Mann BA Karen K. Ballen MD Christine Connolly BS Philip C. Amrein MD Amir T. Fathi MD 《Cancer》2020,126(6):1264-1273
3.
Microglia, as the resident immune cells in the central nervous system, play important roles in regulating neuronal processes, such as neural excitability, synaptic activity, and apoptotic cell clearance. Growth factors can activate multiple signaling pathways in central nervous system microglia and can regulate their immune effects, but whether growth factors can affect the morphological characteristics and ultrastructure of microglia has not been reported. After microinjecting 300 nL of a growth factor cocktail, including 10 μg/mL epidermal growth factor, 10 μg/mL basic fibroblast growth factor, 10 μg/mL hepatocyte growth factor and 10 μg/mL insulin-like growth factor into adult rat cortex, we found that the number of IBA1-positive microglia around the injection area increased significantly, indicating local activation of microglia. All CD68-positive labeling co-localized with IBA1 in microglia. Cell bodies and protrusions of CD68-positive cells were strongly attached to or were engulfing neurons. Characteristic huge phagosomes were observed in activated phagocytes by electron microscopy. The phagosomes generally included non-degraded neuronal protrusions and mitochondria, yet they contained no myelin membrane or remnants, which might indicate selective phagocytosis by the phagocytes. The remnant myelin sheath after phagocytosis still had regenerative ability and formed "myelin-like" structures around phagocytes. These results show that microinjection of a growth factor cocktail into the cerebral cortex of rodents can locally activate microglia and induce selective phagocytosis of neural structures by phagocytes. The study was approved by the Institute of Laboratory Animal Science, Beijing Institute of Basic Medical Sciences(approval No. IACUC-AMMS-2014-501) on June 30, 2014. 相似文献
4.
Ahmed M. Abu El-Asrar Ajmal Ahmad Eef Allegaert Mohammad Mairaj Siddiquei Priscilla W. Gikandi Gert De Hertogh 《Ocular immunology and inflammation》2020,28(4):575-588
ABSTRACT
Purpose
To investigate the expression of IL-11 and its receptor IL-11Rα and to quantify density of CD163+ M2 macrophages in proliferative diabetic retinopathy (PDR). 相似文献5.
背景与目的:CD44分子是众多肿瘤细胞的标志分子,其表达水平与肿瘤细胞的恶性程度有关。该研究探讨CD44基因中的单核苷酸多态性(single nucleotide polymorphism,SNP)位点与云南汉族人群宫颈癌和非小细胞肺癌(nonsmall cell lung cancer,NSCLC)易感性的相关性。方法:选取了CD44基因中的两个SNP位点rs13347和rs8193,采用TagMan基因分型的方法,分析这两个多态性位点在497例宫颈癌患者和500例健康对照个体以及483例NSCLC患者和471例健康对照个体中的分布特征,并分析CD44基因中的多态性位点与云南汉族人群宫颈癌和NSCLC的相关性。结果:rs13347和rs8193位点等位基因和基因型在宫颈癌组和对照组中的分布频率的差异无统计学意义(P>0.05)。而在NSCLC组和对照组的比较中:rs13347和rs8193位点等位基因在NSCLC组和对照组中的分布频率的差异有统计学意义(P=0.020和P=0.004);这两个位点基因型在NSCLC组和对照组中分布频率的差异有统计学意义(P=0.027和P=0.020);其中rs13347位点等位基因C在NSCLC组中的分布频率显著高于对照组,可能是NSCLC发生的风险因素(OR=1.250,95% CI:1.035~1.509),rs8193位点等位基因C在对照组中的分布频率显著高于NSCLC组,可能是NSCLC发生的保护性因素(OR=0.768,95%CI:0.641~0.921)。单倍型分析结果显示,rs13347C-rs8193T和rs13347T-rs8193C在NSCLC组和对照组中的分布频率差异有统计学意义(P=0.003和0.022);该结果说明单倍型rs13347C-rs8193T可能是云南汉族人群NSCLC发生的风险性因素(OR=1.316,95%CI:1.096~1.579)。结论:CD44基因中的两个SNP位点rs13347和rs8193可能与云南汉族人群宫颈癌发病风险无关,而可能与云南汉族人群NSCLC具有相关性。 相似文献
6.
Cis-diamminedichloridoplatinum(II)(CDDP)-based combination chemotherapy is frequently used in gastrointestinal cancer. The synergistic mechanism of all-trans retinoic acid (ATRA), cisplatin (CDDP) and 5-fluorouracil (5-FU) in combination remains unclear. Despite their potent antitumor properties, resistance to CDDP and 5-FU develops frequently in tumors. To clarify this mechanism, we determined the sensitivity to each drug and their combination in two gastrointestinal cancer stem cells (CSCs) subpopulation.Here, we report the identification and separation of CD44+ cells from human gastric carcinoma (AGS) and human esophageal squamous cell carcinoma (KYSE-30) cancer cell lines by magnetic activated cell sorting (MACS). We allowed the CD44± cells to grow 6 days at a subtoxic concentration of ATRA and then treated with different concentration of CDDP and 5-FU for 24 h. The cytotoxicity was examined by cell proliferation MTT assay. Additionally, AO/EB staining was used for detection of apoptotic cells. In order to determine whether the growth inhibition was also associated with changes in cell cycle distribution, cell cycle analysis was performed using flow cytometry.Low concentration of ATRA (1 μM, 6days) followed by 5-FU and CDDP was found to be more effective than either drugs alone, thus resulting in synergistic cytotoxicity in Kyse-30 and AGSCD44± cells. Furthermore, there was an indication that the combination of ATRA with 5FU and CDDP caused an increase in cell cycle arrest in G2/M and G0/G1.We conclude that low concentration of ATRA enhances the cytotoxicity of CDDP and 5FU by facilitating apoptosis and cell cycle arrest in gastrointestinal CSCs and provide a rational basis for the design of novel, well-tolerated CDDP- and 5FU-based chemotherapy in human gastrointestinal carcinoma. 相似文献
7.
目的比较骨填充网袋椎体成形术(Vesselplasty)与经皮椎体后凸成形术(percutaneous kyphoplasty,PKP)治疗 Kümmell 病的临床疗效。方法2015 年 1 月—2018 年 12 月收治 63 例 Kümmell 病患者,其中 28 例采用 Vesselplasty 治疗(Vesselplasty 组),35 例采用 PKP 治疗(PKP 组)。两组患者性别、年龄、病程、骨密度 T 值、骨折节段及术前疼痛视觉模拟评分(VAS)、Oswestry 功能障碍指数(ODI)、伤椎前缘高度、后凸 Cobb 角等一般资料比较,差异均无统计学意义(P>0.05),具有可比性。记录两组手术时间、术中透视时间、骨水泥注射量、骨水泥渗漏率、骨水泥弥散面积率和随访期间并发症发生情况,以及术前、术后 1 d、末次随访时 VAS 评分、ODI、伤椎前缘高度、后凸 Cobb 角。 结果两组患者均获随访,随访时间 12~36 个月,平均 24.2 个月。Vesselplasty 组手术时间、术中透视时间、骨水泥注射量、骨水泥弥散面积率均明显小于 PKP 组(P<0.05)。Vesselplasty 组骨水泥渗漏率(7.14%)明显低于 PKP 组(34.29%)(χ2=5.153,P=0.023)。两组患者术后 1 d 及末次随访时 VAS 评分、ODI、伤椎前缘高度、后凸 Cobb 角均较术前显著改善(P<0.05),术后两组间比较差异均无统计学意义(P>0.05)。随访期间两组均未见术椎再塌陷,Vesselplasty 组邻椎骨折发生率(7.14%)与 PKP 组(14.29%)比较,差异无统计学意义(χ2=0.243,P=0.622)。 结论Vesselplasty 和 PKP 治疗 Kümmell 病疗效相似,均能有效缓解患者疼痛症状,改善生活质量,部分恢复伤椎高度,矫正椎体后凸。但前者具有手术时间短、术中透视时间少、骨水泥渗漏少等优势。 相似文献
8.
《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
9.
10.
目的探讨喉癌患者血小板表面血小板膜糖蛋白Ⅱb/Ⅲa纤维蛋白原受体(PAC-1)、血小板P-选择素(CD62P)阳性表达率以及与患者临床病理特征和复发的关系。方法选取2014年1月~2015年12月间在我院耳鼻喉科手术治疗的116例喉癌患者,随访≥2年,并选取同期在我院体检的健康人群60例为对照组,采用流式细胞仪检测法检测外周血PAC-1和CD62P阳性率,并分析与临床病理特征、复发的关系。结果喉癌患者PAC-1和CD62P阳性表达率分别为(17.82±1.76)%和(22.87±3.13)%,明显高于健康人群(P<0.05);而且在喉癌患者PAC-1表达和CD62P表达呈正相关性(r=0.238,P<0.05)。T3-T4分期或N2-N3分期患者PAC-1和CD62P阳性表达率高于T1-T2分期或N0-N1分期患者(P<0.05)。另外远处转移组PAC-1和CD62P阳性表达率高于未发生转移组(P<0.05);随访期间有24例患者复发,复发率为20.69%。复发喉癌患者PAC-1、CD62P阳性表达率分别为(17.02±0.85)%和(21.84±1.17)%,明显高于未复发的喉癌患者(P<0.05)。经Logistics回归分析,PAC-1和CD62P是喉癌患者复发的独立危险因素(P<0.05)。结论PAC-1和CD62P阳性表达率与喉癌患者T分期、淋巴结转移和远处转移密切相关,同时可作为喉癌局部复发、区域淋巴结转移、远处转移的预测指标。 相似文献