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21.
《Biomaterials》2015
Malignant glioma is the most common intracranial tumor with a dismal prognosis. The radiosensitizing effect of silver nanoparticles (AgNPs) on glioma both in vitro and in vivo had been demonstrated in the previous studies of our group. However, the underlying mechanism is still unclear. Consistent with previous studies, a size and dose dependent antitumor effect and significant radiosensitivity enhancing effect of AgNPs were observed in our experiment system. We also found that cell protective autophagy could be induced by AgNPs and/or radiation, which was verified by the use of 3-MA. The mechanism through which had autophagy and the enhancement of radiosensitivity taken place was further investigated with inhibitors of ERK and JNK pathways. We demonstrated that ERK and JNK played pivotal roles in the radiosensitivity enhancement. Inhibiting ERK and JNK with U0126 and SP600125 respectively, we found that the autophagy level of the cells treated with AgNPs and radiation were attenuated. Moreover, SP600125 down-regulated the apoptosis rate of the co-treated cells significantly. Taken together, the present study would have important impact on biomedical applications of AgNPs and clinical treatment for glioma. 相似文献
22.
Yeon Seok Lee June Hyunkyung Lee Jae Eun Choi Joo Young Kim Tae Young Han 《Pediatric dermatology》2021,38(1):290-291
Erythema induratum of Bazin (EIB) is a form of tuberculid resulting from hypersensitivity to tuberculosis antigen. EIB occurs most commonly in middle‐aged women and is not typically seen in children. Here, we present a rare case of EIB, presenting as a chronic nodular panniculitis, in a 10‐year‐old Korean boy. 相似文献
23.
《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
24.
Anastasiia Panfilova Sarah E. Shelton Cristina Caresio Ruud J.G. van Sloun Filippo Molinari Hessel Wijkstra Paul A. Dayton Massimo Mischi 《Ultrasound in medicine & biology》2019,45(2):539-548
Dynamic contrast-enhanced ultrasound (DCE-US) has been proposed as a powerful tool for cancer diagnosis by estimation of perfusion and dispersion parameters reflecting angiogenic vascular changes. This work was aimed at identifying which vascular features are reflected by the estimated perfusion and dispersion parameters through comparison with acoustic angiography (AA). AA is a high-resolution technique that allows quantification of vascular morphology. Three-dimensional AA and 2-D DCE-US bolus acquisitions were used to monitor the growth of fibrosarcoma tumors in nine rats. AA-derived vascular properties were analyzed along with DCE-US perfusion and dispersion to investigate the differences between tumor and control and their evolution in time. AA-derived microvascular density and DCE-US perfusion exhibited good agreement, confirmed by their spatial distributions. No vascular feature was correlated with dispersion. Yet, dispersion provided better cancer classification than perfusion. We therefore hypothesize that dispersion characterizes vessels that are smaller than those visible with AA. 相似文献
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26.
[摘要] 目的 评估直接抗病毒药物(direct antivirus agent, DAA)治疗肝移植术后HCV感染复发的有效性和安全性。方法?回顾性分析首都医科大学附属北京佑安医院2011年2月—2018年12月收治的14例肝移植术后HCV感染复发患者的DAA治疗临床数据,比较患者基线与治疗结束后肝肾功能、血常规、凝血功能、病毒学水平以及无创纤维化评分天冬氨酸转氨酶血小板比率指数(aspartate aminotransferase-platelet ratio index, APRI)的差异。利用电子病历系统和电话随访收集患者治疗期间不良反应发生情况。结果?所有患者均在治疗结束时达到病毒学清除,12周、24周持续病毒学应答率均为100%,DAA治疗后随访17~44个月,期间均未见病毒学复发。与基线水平相比,治疗终点时ALT、AST、TBIL、γ-谷氨酰转移酶以及无创纤维化评分APRI显著下降,WBC、HGB、PLT、CRE、肾小球滤过率和血糖等指标均未见显著变化。DAA治疗期间共3例患者发生不良反应,均为轻度,可自然缓解。结论?肝移植术后HCV感染复发的DAA治疗是安全有效的。 相似文献
27.
28.
《Journal of Medical Imaging and Radiation Sciences》2015,46(4):442-449
The purpose of this literature review is to investigate clinical treatment methods of total body irradiation within the context of a clinical department adopting a paediatric cohort with no existing technique. An extensive review of the literature was conducted using PubMed, Science Direct, Google Scholar, and Clinicians Knowledge Network. Articles were limited to nonhelical tomotherapy, nonparticle therapies, and those using hyperfractionated regimes. Total marrow irradiation was excluded because of national treatment and trial limitations. Of the numerous patient positioning methods present within the literature, the most comfortable and reproducible positioning methods for total body irradiation include both supine and the supine and/or prone combination. These positions increased stability and patient comfort during treatment, while also facilitating computed tomography data acquisition at the simulation stage. Ideally, dose calculations should be performed using a three-dimensional treatment planning system and quality assurance procedures that include in vivo dosimetry measurements. The available literature also suggests inhomogeneity correction factors and intensity modulation are superior to conventional open field techniques and should be implemented within developing protocols. Dynamic machine dose modulation is suggested to reduce department impact, removing the need for tissue compensators and accessory shielding devices, while providing significant improvements to treatment time and dose accuracy. Further long-term survival and intensity modulation studies are warranted, including direct comparisons of both dose modulation and treatment efficiency. 相似文献
29.
《The journal of sexual medicine》2020,17(8):1423-1433
BackgroundProstatic radiation therapy (RT) often causes erectile dysfunction (ED) and the mechanisms governing RT-induced ED are unclear with a lack of therapeutic strategies.AimTo determine the effects of ex vivo RT on major pelvic ganglion (MPG) neuron survival, and neurite growth in whole vs dissociated culture.MethodsMPGs were removed and irradiated (0 or 8 Gy) from male Sprague Dawley rats. For dissociated culture, MPG neurons were digested in collagenase/dispase and cultured on coverslips. Immunofluorescent staining for beta-tubulin III (TUBB3; neuron marker), neuronal nitric oxide synthase (nNOS; nitrergic marker), tyrosine hydroxylase (TH; sympathetic marker), and terminal deoxynucleotidyl transferase dUTP nick end labeling assessed neurite length, branching, autonomic neuron density, and apoptosis. For whole organ culture, MPGs were grown in Matrigel. Gene expression of apoptotic markers (caspase 1, 3), TUBB3, nNOS, TH, and Schwann cells (Sox10, Krox20, glial fibrillary acid protein) was measured in whole organ cultured MPGs by quantitative polymerase chain reaction.OutcomesAfter 72 hours, neurite length, branching, autonomic neuron density, and apoptosis were assessed, and gene expression was measured.ResultsRT increased apoptosis in dissociated neurons measured by terminal deoxynucleotidyl transferase dUTP nick end labeling (P < .001) and whole MPG culture via upregulation of caspase 3 gene expression (P < .05). Nitrergic neurons were markedly decreased in irradiated dissociated culture (P < .05), while nNOS gene expression was upregulated in irradiated whole organ culture (P < .05). The proportion of dissociated sympathetic neurons and whole organ TH gene expression remained unchanged after RT. Interestingly, RT dissociated neurites were 22% shorter than controls, while RT whole organ neurites were 15% longer than controls (P < .01). MPG Schwann cells markers (Sox10, Krox20) were elevated after RT in whole organ culture.Clinical TranslationProstatic RT leads to increased neuronal cell death and less erectogenic nitrergic neurons contributing to ED.Strengths & LimitationsThe advantages of dissociated neuron culture include distinct neurites which are easily measured for apoptosis, length/branching, and specific neuron types. In contrast, whole MPG culture is advantageous as it contains all the supporting cells present in vivo.ConclusionThe 2 different culture methods demonstrated opposing neurite growth after RT indicating the importance of supporting cell network to promote pelvic neuron neuritogenesis and survival following RT.Randolph JT, Pak ES, Koontz BF, et al. Ex Vivo Radiation Leads to Opposing Neurite Growth in Whole Ganglia vs Dissociated Cultured Pelvic Neurons. J Sex Med 2020;17:1423–1433. 相似文献
30.
目的 初步探讨应用艾尔巴韦/格拉瑞韦治疗慢性丙型肝炎(CHC)患者的疗效。方法 2017年3月~2018年3月仙桃市第一人民医院感染病科收治的CHC患者82例,被随机分为对照组41例和观察组41例,分别给予聚乙二醇干扰素-α联合利巴韦林治疗和艾尔巴韦/格拉瑞韦治疗,两组均连续治疗24周。采用RT- PCR法检测血清 HCV RNA,采用全基因序列测定法行病毒基因分型。比较两组早期病毒学应答(EVR)、治疗结束时病毒学应答(ETVR)和持续病毒学应答(SVR)。结果 在治疗结束时,观察组血清丙氨酸氨基转移酶(ALT)水平为(47.9±19.7)U/L,显著低于对照组【(63.5±21.2)U/L,P<0.05】,天冬氨酸氨基转移酶(AST)水平为(55.5±22.3)U/L,显著低于对照组【(81.3±25.8)U/L,P<0.05】;观察组EVR、ETVR和SVR分别为48.8%、63.4%和70.7%,与对照组的41.5%、53.7%和65.8%比,无统计学差异(P>0.05);18例观察组非HCV Ⅰ型感染者EVR、ETVR和SVR分别为88.9%、94.4%和88.9%,显著高于同组23例HCV Ⅰ型感染者(分别为52.2%、60.9%和52.2%, P<0.05),而与对照组15例非HCV Ⅰ型感染者比,无统计学差异(分别为86.7%、93.3%和73.3%, P>0.05);观察组SVR12为87.8%(36/41),显著高于对照组的73.2%(30/41,P<0.05)。结论 应用直接抗病毒(DAA)药物艾尔巴韦/格拉瑞韦治疗CHC患者近期疗效达到,但远期疗效似优于标准治疗方案, 值得临床进一步验证。 相似文献