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21.
AimWe conducted a study to validate the MDASI-HN based nomogram, which is used to predict the acute toxicities in head and neck cancer patients undergoing radiation therapy with or without chemotherapy.BackgroundTolerance to radiation varies from patient to patient and also depends on various other factors like tumor volume, dose of radiation, chemotherapy. Predicting the toxicities allow us to identify potential candidates who are likely to have a higher toxicity and, in addition, evaluates the nomogram when done on an independent group of patients.Materials and MethodsSixty biopsy confirmed head and neck cancer patients undergoing radiation were the subjects of the study. The patients completed patient reported outcome instrument (PRO) MDASI-HN questionnaire at the beginning and at the fifth week of radiation. The baseline score obtained was used to obtain the predicted score using nomogram. The nomogram was also externally validated as per the TRIPOD guidelines.ResultsThe mean baseline, predicted and score at the fifth week were 27.28 ± 11.04, 73.33 ± 15.51 and 82.62 ± 17.67, respectively, for all sub-sites. A positive, significant correlation (p < 0.01) between the predicted score and the score at the fifth week was seen across all sub sites such as Oral cavity (p = 0.05), Oropharynx (p = 0.02), Hypo pharynx (p = 0.02) and Larynx (p = 0.02).ConclusionThe MDASI-HN questionnaire based nomogram is simple, easily doable and takes into consideration the initial symptoms as well the treatment details; thereby, it is able to predict the toxicities accurately.  相似文献   
22.
摘要:膀胱癌是临床常见的发生在泌尿系统的恶性肿瘤,该病的发病率呈现逐年升高的趋势,其复发率也相对较高。早期诊断和定期随访是保证膀胱癌患者长期生存的关键。对于膀胱癌的诊断以及患者的随访通常凭借膀胱镜检查或尿脱落细胞学的测定。然而,前者的检查费用较为昂贵,且属于有创诊断;后者则具有检查敏感性相对较低的特点,还存在较大程度受病理科诊断医生主观因素影响的局限,目前还没有尿液生物标志物可以替代传统的诊断方法。膀胱肿瘤具有广泛的异质性,不同的疾病表型具有不同的分子差异。因此,引入尿液生物标志物来诊断疾病,评估疾病的侵袭性、进展的风险、复发的可能性和预后具有重要的临床价值。本文总结了目前尿液所含生物标志物诊断膀胱癌的研究现状,并对此领域的主要研究进展进行综述。  相似文献   
23.
摘要 目的:探讨切开与闭合复位空心钉内固定对移位股骨颈骨折患者骨折复位质量和髋关节功能的影响。方法:本研究为回顾性研究,选取98例移位股骨颈骨折患者的临床资料,根据手术方式的不同将患者分为A组(n=50,切开复位)和B组(n=48,闭合复位),比较两组患者优良率、骨折复位质量、髋关节功能、围术期指标、术后并发症发生率和二次手术发生率。结果:A组患者术后6个月的优良率为78.00%(39/50),高于B组的58.33%(28/48)(P<0.05)。两组术后负重下地时间、术中透视时间比较无差异(P>0.05);B组手术时间、住院时间短于A组,术中出血量少于A组(P<0.05)。两组患者术后1个月、术后3个月、术后6个月髋关节功能Harris评分均较术前升高,且A组高于B组(P<0.05)。两组二次手术及并发症发生率比较无差异(P>0.05)。A组Ⅰ型、Ⅱ型的例数均多于B组,Ⅲ型例数少于B组(P<0.05)。结论:与闭合复位空心钉内固定相比,切开复位空心钉内固定虽损伤较大,但其术后骨折复位质量和髋关节功能改善效果更佳,且不增加并发症发生率和二次手术发生率。  相似文献   
24.
BackgroundWe investigated the relationship between genetic alterations and 18F-FDG PET/CT findings in head and neck squamous cell carcinoma (HNSC).MethodsUsing mRNA-sequences of HNSC samples (480 patients) from the Cancer Genome Atlas (TCGA) portal, gene coexpression networks were constructed via a weighted correlation network analysis (WGCNA) algorithm, and their association with the tumor-to-blood signal ratio on 18F-FDG PET/CT data (21 patients) was explored. An elastic-net regression model was developed to estimate the PET tumor-to-blood ratio from the gene networks and to derive an FDG signature score (FDGSS). The FDGSS was evaluated with regard to clinical variables and general mutational profiles, as well as alterations to oncogenic signaling pathways.FindingsThe FDGSS values differed across clinical stages (p = 0.027), HPV-status (p< 0.001), and molecular subtypes of HNSC (p< 0.001). Multivariate Cox regression demonstrated that FDGSS was an independent predictor for overall (p = 0.019) and progression-free survival (p = 0.024). FDGSS positively correlated with total mutation rate (p = 0.016), aneuploidy (p < 0.001), and somatic copy number alteration scores (p < 0.001). CDKN2A in the cell cycle pathway (q = 0.014) and the TP53 gene in the TP53 pathway (q = 0.005) showed significant differences between high and low FDGSS patients.ConclusionFDGSS based on the gene coexpression network was associated with the mutational landscape of HNSC. 18F-FDG PET/CT is therefore a valuable tool for the in vivo imaging of these cancers, being able to visualize the glucose metabolism of the tumor and allow inferences to be made on the underlying genetic alterations in the tumor.  相似文献   
25.
Previous studies have demonstrated that experimental type 1 diabetes induced by streptozotocin causes alterations in the biochemical and functional properties of several receptor systems in the rat bladder. However, the exact mechanism involved in the pathophysiology of voiding dysfunction in type 2 diabetic patients is unknown. Because the GK rat is a widely accepted genetically determined rodent model for human type 2 diabetes, we investigated diabetes-induced changes in the bladder smooth muscle of the GK rats at several time points. Male GK rats and age-matched Wistar rats, as controls, were maintained for 4, 8, 16, and 32 weeks. Contractile responses to KCl, carbachol, ATP, and electrical field stimulation (EFS) were measured by using the isolated muscle bath techniques. Acetylcholine (ACh) release induced by EFS from bladder muscle strips was measured by using high-performance liquid chromatography coupled with a microdialysis procedure. Maximum contractile responses to carbachol and ATP, the release of ACh, and tissue sorbitol levels were similar in bladders from GK and control rats until 8 weeks of age. At 16 weeks of age, however, the contractile responses to carbachol and ATP, and tissue sorbitol levels were increased, and the EFS-induced ACh release was decreased in GK rats compared with controls. Although the maximum contractile responses to EFS were unchanged until 16 weeks of age, they were decreased in 32-week-old GK rats, compared with controls. Our data indicate the presence of age-related alterations in the biochemical and functional properties of the bladder in type 2 diabetic GK rats.  相似文献   
26.

Background

IMRT provides highly conformal dose distributions creating non uniform spatial intensity using different segments in the beam.

Material & Methods and Results

Different retrospective studies have shown a high capability of IMRT to treat tumours close to the base of skull. Prospective studies have shown a decrease in xerostomia compared with conventional 3D conformal treatment (3DCRT). Modulation of intensity is performed by the movement of the multileaf collimator (MLC) that can deliver the radiation in different ways, such as static field segments, dynamic field segments and rotational delivery (arc therapy and tomotherapy). There are slight differences among the different techniques in terms of homogeneity, dose conformity and treatment delivery time.

Conclusions

The best method to deliver IMRT will depend on multiple factors such as deliverability, practicality, user training and plan quality.  相似文献   
27.
28.
Head and neck squamous cell carcinoma (HNSCC) is the sixth leading cancer in the world; the main risk factors are alcohol and tobacco use. Advancements in therapies have yet to improve the prognosis of HNSCC. The connection between diabetes and cancer is being recognized, and metformin has been shown to decrease cancer incidence in diabetic patients. Accordingly, here, for the first time, we investigated metformin’s efficacy on the growth and viability of human HNSCC FaDU and Detroit cells. Our results show that metformin treatment (5–20 mM) dose-dependently inhibits the growth of both cell lines. In FaDU cells, metformin caused 18–57% and 35–81% growth inhibition after 48 and 72 h treatments, respectively. Similarly, in Detroit 562 cells, 48 and 72 h metformin treatment resulted in 20–57% and 33–82% inhibition, respectively. Mechanistically, metformin caused G1 arrest, which coincided with a decrease in the protein levels of CDKs (2, 4 and 6), cyclins (D1 and E) and CDK inhibitors (p15, p16, p18 and p27), but no change in p19 and p21. Metformin also decreased the levels of oncogenic proteins Skp2 and β-Trcp. In other studies, metformin decreased the phosphorylation of 4E-BP1 at Ser65, Thr37/46 and Thr70 sites, but drastically increased the phosphorylation of EF2 at Thr56 and AMPK at Thr172, which results in global translational inhibition. In summary, the observed wide spectrum of mechanistic effects of metformin on HNSCC cells provides support for the anticancer capability of the drug and its potential use in future therapies.  相似文献   
29.
目的:观察卡介苗(BCG)单独作用膀胱肿瘤细胞、正常膀胱移行上皮细胞及其代谢产物作用上述细胞后细胞生长情况及各自细胞培养液上清液中细胞因子(TNF-α.、IL-10、IFN-γ)浓度的变化,探讨其在卡介苗治疗膀胱肿瘤中可能的作用机制。方法:构建大鼠膀胱肿瘤模型,并原代培养大鼠膀胱肿瘤细胞及正常膀胱移行上皮细胞。分别用BCG,普通培养液和细胞培养的代谢产物作用上述细胞。酶联接免疫吸附剂测定法(ELISA法)检测各组细胞上清液中肿瘤坏死因子-α(TNF-α)、白细胞介素-10(IL-10)、干扰素-γ(IFN-γ)的浓度。结果:ELISA法检测各组细胞上清液中TNF-α、IL-10的浓度改变有显著差异,而IFN-γ的浓度无显著差异。结论:BCG可以直接刺激肿瘤细胞自身分泌细胞因子(TNF-α、IL-10)参与调节抑制肿瘤细胞的生长。  相似文献   
30.
薛庆  于垂恭  于磊  武国军  袁建林 《生物磁学》2013,(25):4829-4832,4850
目的:已经有研究证明肝再生磷酸酶3(PhosphataseofRegeneratingLiver-3,PRL-3)在消化道肿瘤的发生发展过程中起到重要作用,但其在膀胱癌中发挥何种作用尚不清楚,本次研究主要探寻PRL-3在膀胱癌细胞T24中作用,以求为膀胱癌的治疗提供新思路。方法:采用siRNA干涉的方法下调T24中PRL-3蛋白表达水平,通过westernblot方法检测干涉效果,绘制细胞生长曲线、构建裸鼠种植瘤模型,检测PRL-3下调对细胞体外及体内增殖的影响。结果:我们所设计的siRNA能够下调PRL-3在A498细胞中的表达(F=7.26,P〈0.05),细胞生长曲线显示下调PRL-3能够抑制细胞的增殖,这种作用从干涉后的第60h开始,随时间增加作用愈加明显(F≥8.35,P〈0.05);动物实验表明,siRNA下调PRL-3能够抑制T24细胞在活体内的增殖,从干涉后第21天开始这种作用开始体现出来(F≥10.46,P〈0.05),并且干涉组的肿瘤肿瘤明显低于两个对照组(F=13.63,P〈0.05)。结论:我们构建的siRNA能够在T24细胞中实现对PRL.3蛋白的下调,siRNA介导的PRL-3蛋白下调能够明显抑制T24细胞在活体外及活体内的增殖,这初步证明PRL-3在膀胱癌中发挥重要的作用。随着我们对PRL-3分子进一步深入的了解,揭示其发挥作用的具体机制,PRL-3很可能成为膀胱癌基因治疗的新靶点。  相似文献   
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