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21.
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   
22.
Context Withania somnifera (L.) Dunal is traditionally used for treating various ailments, but lacks scientific evaluation.

Objective This study evaluates Withania somnifera (WS) for its effect on platelet activity and inflammatory enzymes.

Materials and methods Aqueous and ethanolic (1:1) leaf extracts were subjected to in vitro indirect haemolytic activity using Naja naja venom, human platelet aggregation was quantified for lipid peroxidation using arachidonic acid (AA) as agonist and 5-lipoxygenase (5-LOX) levels were determined using standard spectrometric assays. Further, molecular docking was performed by the ligand fit method using molegro software package (Molegro ApS, Aarhus, Denmark).

Results The study found that aqueous and ethanol extracts have very negligible effect (15%) with an IC50 value of 13.8?mg/mL on PLA2 from Naja naja venom. Further, extracts of WS also had very little effect (18%) with an IC50 value of 16.6?mg/mL on malondialdehyde (MDA) formation. However, a 65% inhibition of 5-LOX with an IC50 value of 0.92?mg/mL was observed in 1:1 ethanol extracts. The same was evident from SAR model with the active ingredient withaferin A binding predominantly on Phe 77, Tyr 98, Arg 99, Asp 164, Leu 168, Ser 382, Arg 395, Tyr 396 and Tyr 614 with an atomic contact energy value of??128.96 compared to standard phenidone (?103.61). Thus, the current study validates the application of WS for inflammatory diseases.

Conclusion This study reveals the inhibitory potential of W. somnifera on inflammatory enzymes and platelet aggregation. Thus, WS can serve as a newer, safer and affordable medicine for inflammatory diseases.  相似文献   
23.
 Û   ¬  ࿞ ¿   ¬ í  &#x; ྽   &#x;         &#x; 《中国肺癌杂志》2021,24(3):161
背景与目的以免疫检查点抑制剂(immune checkpoint inhibitors, ICIs)为代表的免疫治疗越来越广泛地应用于肺癌治疗。然而,对于程序性死亡受体配体1(programmed cell death-ligand 1, PD-L1)高表达,即肿瘤比例评分(tumor proportion score, TPS)≥50%的晚期非小细胞肺癌(non-small cell lung cancer, NSCLC)患者,采用单纯免疫治疗还是免疫联合化疗在临床上仍存争议。本研究旨在评估PD-L1高表达的晚期NSCLC患者接受单纯免疫治疗与免疫联合化疗的疗效。方法本研究回顾性分析了49例PD-L1高表达晚期NSCLC患者的临床资料。PD-L1表达采用22C3抗体行免疫组化染色,按TPS判读PD-L1表达水平。比较不同临床特征分组患者的客观缓解率(objective response rate,ORR)和无进展生存时间(progression free survival, PFS)。结果免疫单药与免疫联合化疗组的ORR分别为47.1%(8/17)和43.8%(14/32),差异无统计学意义(P=0.825)。免疫单药与免疫联合化疗组的中位PFS分别为8.0个月和6.8个月,差异无统计学意义(P=0.502)。并对本组PD-L1高表达患者免疫治疗的预测因素进行了分析,结果显示,一线免疫治疗ORR(12/19, 63.2%)显著优于二线及以上免疫治疗(10/30, 33.3%),差异有统计学意义(P=0.041),二者间PFS无差异。年龄、性别、吸烟史、功能状态评分(performance status, PS)、病理类型、肿瘤大小、肿瘤淋巴结转移(tumor node metastasis, TNM)分期与ORR和PFS不相关。结论PD-L1高表达的晚期NSCLC患者接受免疫单药和免疫联合化疗的疗效相近。PD-L1高表达患者一线免疫治疗的ORR更佳。对此类人群的最佳治疗方案有待于前瞻性临床研究进一步探索。  相似文献   
24.
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   
25.
Epidermolysis bullosa simplex (EBS) is a skin fragility disorder resulting from mutations of structural proteins in the epidermis. We provide a brief report of long‐term survival and reproduction in a mother with EBS due to keratin 5 (KRT5) c.1429G > A (p.E477K) mutation, which causes a particularly severe form of the disease.  相似文献   
26.
目的探究N6-甲基腺嘌呤(m6A)去甲基化酶ALKBH5与弱精症的相关性。方法收集精液标本30份,包括弱精症患者与健康者精液标本各15份,密度梯度离心纯化精子,使用液相色谱与质谱联用(LC-MS/MS)检测精子RNA的m6A水平,使用实时荧光定量PCR法检测ALKBH5相对表达水平。结果弱精症患者m6A水平明显高于健康者,ALKBH5相对表达水平低于健康者,差异均有统计学意义(P<0.05)。精子活动度参数相关性分析结果显示,ALKBH5相对表达水平与前向运动精子数和非前向运动精子数呈正相关(r=0.512、0.377,P<0.05),与不动精子数呈负相关(r=-0.497,P<0.05);m6A与前向运动精子数和非前向运动精子数呈负相关(r=-0.442、-0.425,P<0.05),与不动精子数呈正相关(r=0.528,P<0.05)。结论在弱精症患者中,m6A及其去甲基化酶ALKBH5与精子活动度具有相关性。  相似文献   
27.
目的探讨对先天性耳甲腔型小耳畸形患者行全扩张法全耳再造术后,利用残耳皮瓣改善再造耳颅耳沟的效果。方法回顾分析 2012 年 1 月—2017 年 1 月收治的 150 例先天性耳甲腔型小耳畸形患者。其中男 92 例,女 58 例;年龄 6.5~35.0 岁,平均 11.1 岁。采用一期扩张器埋置、二期全扩张法全耳再造术后发现上部颅耳沟浅显;于 6~12 个月后行三期再造耳修整。将残耳垂通过“Z”字改型转移以再造耳垂。在残耳上部作蒂在轮屏切迹的残耳上部皮瓣,弧形切开松解并加深上部颅耳沟,将上部残耳皮瓣向颅耳沟创面旋转推进缝合以覆盖创面;将带皮下组织蒂的残耳软骨组织瓣插入支架底部形成的腔隙内,并缝合固定,以增加支架的高度;耳甲腔区其余残耳皮瓣用以覆盖耳甲腔创面。结果术后拆线时 1 例患儿皮瓣远端出现直径约 0.5 cm 的表皮水疱,经换药 2 周后愈合;其余患者皮瓣成活良好。患者均获随访,随访时间 6~12 个月,平均 9.6 个月。再造耳上部颅耳沟均明显加深,再造耳支架高度不同程度增加,双耳对称性佳,耳甲腔无明显挛缩变小,再造耳外观满意。再造耳上部表面毛发明显减少,耳周发际线上移。结论采用耳甲腔型小耳畸形的残耳皮瓣及残耳软骨瓣转移,不仅可加深颅耳沟,而且可增加上部支架的高度,术后颅耳沟变形较轻,再造耳与正常耳廓的对称性更佳。  相似文献   
28.
The objectives of this study were to evaluate survival in 141 patients with stage II–IV oral squamous cell carcinoma (OSCC) treated with preoperative intra-arterial chemotherapy with docetaxel, cisplatin, and peplomycin combined with intravenous chemotherapy using 5-fluorouracil (IADCPIVF) via the superficial temporal artery, and to clarify the prognostic factors. The study population included 59 patients with stage II OSCC, 34 with stage III, and 48 with stage IV. After IADCPIVF, 139 patients underwent surgery; minimally invasive surgeries (MIS) including excisional biopsy were performed on 96 patients with a remarkably good response to IADCPIVF. The primary tumour response rate was 99.3% (complete response rate 56.7%, good partial response rate 17.0%, fair partial response rate 25.5%). Additionally, there were no serious adverse events associated with IADCPIVF. The 5-year overall survival rate was 74.6% (stage II 83.6%, stage III 72.7%, stage IV 64.8%). In the multivariate analysis of survival, T classification and clinical tumour response were significant prognostic factors. Eight (8.3%) of the patients who received MIS had primary recurrence and six were salvaged. In conclusion, IADCPIVF is safe and efficacious for treating OSCC, and MIS could reduce the extent of primary tumour resection in the case of a remarkably good response.  相似文献   
29.
《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   
30.
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   
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