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1.
《Revista brasileira de otorrinolaringologia (English ed.)》2020,86(3):321-326
IntroductionMany studies have been done on proteomics, genomics, epigenetic, immunogenetics in many body fluids. Among these, circulating cell-free DNA (ccfDNA) entered the literature in 1948, but it has not been studied for many years due to technological deficiencies. Following recent advances, geno-metastasis has been mentioned and new research is needed in this area. ccfDNA is known to be an important biomolecule in this regard.ObjectiveThe presence of cell-free DNA in the circulatory system may offer a tremendous opportunity to provide novel biomarkers for thyroid diseases. This experimental study was conducted to determine the amount of ccfDNA in different thyroid diseases, then to evaluate whether the ccfDNA concentration varied between the disease groups and control group.MethodsIn total, we included 121 individuals in the present study. We collected blood samples and then determined the ccfDNA concentration in plasma of collected blood samples from three groups: thyroiditis (n = 33), benign (n = 37), and malignant (n = 30) and from a control group (n = 21).ResultsThe median values of the ccfDNA groups were found as 1610, 1665, 1685 and 576 ng/mL for the thyroiditis, benign, malign, and control groups, respectively. Findings showed that the ccfDNA of the three groups was significantly higher than the control (p < 0.0001). Each group was compared in terms of ccfDNA and the p-values of benign-thyroiditis, benign-malign, and thyroiditis-malign were 0.09, 0.65, and 0.29, respectively.ConclusionsThe clear differences between thyroid diseases and controls suggest that ccfDNA is worthy of attention as a biomarker for further evaluation of different thyroid diseases. Likewise, it might indicate a clear tendency that ccfDNA can also be used to distinguish different thyroid diseases. 相似文献
2.
目的:探讨负压创面治疗技术(Vacuum assisted closure,VAC)结合游离植皮治疗儿童大面积皮肤缺损疗效及对患儿生活质量的影响。方法:选取2015年2月-2019年2月笔者医院收治的60例大面积皮肤缺损患儿作为研究对象,按照随机数表法分为干预组和对照组,每组30例。对照组采用游离植皮术治疗,干预组在对照组的基础上结合VAC治疗,以皮片成活时间、皮片成活率、换药次数及住院天数评估疗效,以长海痛尺分级法评估患儿疼痛等级,以抑郁自评量表(Self-rating depression scale,SDS)、焦虑自评量表(Self-rating anxiety scale,SAS)评估患儿心理状态,以术后不良反应发生率评估患儿预后情况,以自制生活质量表评估患儿生活质量水平。结果:干预组患儿皮片成活时间、换药次数与住院天数均小于对照组,差异有统计学意义(P<0.05)。干预组患儿皮片成活率为93.33%高于对照组的76.67%,差异有统计学意义(P<0.05)。干预组治疗后疼痛感、SDS与SAS评分低于治疗前,且低于对照组,差异有统计学意义(P<0.05)。干预组患儿术后不良反应发生率为6.67%显著低于对照组23.33%,差异有统计学意义(P<0.05)。两组治疗前活动能力、心理健康及社交能力均低于治疗后,干预组治疗后活动能力、心理健康及社交能力均高于对照组(P<0.05)。结论:VAC结合游离植皮治疗儿童大面积皮肤缺损疗效显著,能有效降低患儿生理疼痛与心理焦虑,减少伤口感染等不良反应的发生,提高患儿生活质量,具有推广价值。 相似文献
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目的 探究醛糖还原酶和晚期糖基化终末产物受体对糖尿病视网膜病变神经元凋亡的影响。方法 Wistar大鼠36只,随机分为对照组、模型组、转染组,后两组建立糖尿病大鼠模型。模型建立成功后,构建含有晚期糖基化终末产物受体siRNA的质粒并利用慢病毒转染入转染组大鼠体内。造模后4周、8周、12周,记录各组大鼠体质量及空腹血糖。造模后9周,禁食6 h,测定口服葡萄糖耐量。造模后12周,处死全部大鼠后,TUNEL法检测各组大鼠视网膜神经元凋亡情况,荧光分光光度计测定醛糖还原酶活性,Western blotting法测定晚期糖基化终末产物受体的表达,RT-PCR检测视网膜中Bcl-2和Bax mRNA相对表达量。结果 造模后4周、8周、12周,转染组和模型组的大鼠体质量均低于对照组(均为P<0.05);造模后12周,转染组大鼠体质量高于模型组(P<0.05)。造模后4周、8周、12周,各组内大鼠空腹血糖水平均无明显变化(均为P>0.05),转染组和模型组大鼠的空腹血糖水平均高于对照组(均为P<0.05)。模型组和转染组大鼠在口服葡萄糖后30 min时,血糖水平均高于对照组(均为P<0.05);在120 min时分别下降至最低,但仍高于对照组(均为P<0.05)。模型组和转染组的视网膜神经元凋亡指数、醛糖还原酶活性、晚期糖基化终末产物受体和Bax mRNA相对表达量均高于对照组(均为P<0.05),且转染组均高于模型组(均为P<0.05)。模型组和转染组的Bcl-2 mRNA相对表达量均低于对照组(均为P<0.05),转染组低于模型组(P<0.05)。结论 晚期糖基化终末产物结合受体后产生大量的氧自由基损伤,可能是导致糖尿病视网膜神经元凋亡,进而导致糖尿病视网膜病变发生的机制之一。 相似文献
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5.
Sentinel lymph node biopsy for 102 patients with primary cutaneous melanoma at a single Japanese institute 下载免费PDF全文
Masaki Otsuka Osamu Yamasaki Tatsuya Kaji Keiji Iwatsuki Kenji Asagoe 《The Journal of dermatology》2015,42(10):954-961
Sentinel lymph node biopsy (SLNB) is a widely accepted standard procedure for patients with clinically localized melanoma. Melanoma prevalence and Clark's subtype differ between Asians and Caucasians. Here, we evaluated our experience on SLNB for cutaneous melanoma in a Japanese population. SLNB was performed for patients with melanoma between July 2000 and June 2014. We retrospectively analyzed 102 patients regarding association of clinicopathological features with sentinel lymph node (SLN) status, melanoma‐specific survival (MSS) and disease‐free survival (DFS). A positive SLN was significantly associated with primary Breslow thickness. Compared with 43 patients with negative SLN, 59 patients with positive SLN had significantly shorter MSS (5‐year survival rate, 94.3% vs 63.2%; P = 0.0002) and DFS (5‐year survival rate, 92.7% vs 63.4%; P = 0.0004). According to our subgroup analyses, nine patients with positive non‐SLN had significantly shorter MSS compared with 32 patients with negative non‐SLN (5‐year survival rate, 32.4% vs 68.5%; P = 0.0273). The survival of 51 Japanese patients with acral lentiginous melanoma (ALM) was not inferior to the survival of patients with other Clark's subtype. Breslow thickness is an important factor for both MSS and DFS, and the status of SLN is the most predictive prognostic factor in Japanese patients with clinically localized melanomas, as in case of Caucasians. Features of ALM may be different between Asians and Caucasians. 相似文献
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7.
《Vaccine》2019,37(47):6987-6995
Vero cells are nowadays widely used in the production of human vaccines. They are considered as one of the most productive and flexible continuous cell lines available for vaccine manufacturing. However, these cells are anchorage dependent, which greatly complicates upstream processing and process scale-up. Moreover, there is a recognized need to reduce the costs of vaccine manufacturing to develop vaccines that are affordable worldwide. The use of cell lines adapted to suspension growth contributes to reach this objective.The current work describes the adaptation of Vero cells to suspension culture in different serum free media according to multiple protocols based on subsequent passages. The best one that relies on cell adaption to IPT-AFM an in-house developed animal component free medium was then chosen for further studies. Besides, as aggregates have been observed, the improvement of IPT-AFM composition and mechanical dissociation were also investigated.In addition to IPT-AFM, three chemically defined media (CD293, Hycell CHO and CD-U5) and two serum free media (293SFMII and SFM4CHO) were tested to set up a serum free culture of the suspension-adapted Vero cells (VeroS) in shake flasks. Cell density levels higher than 2 × 106 cells/mL were obtained in the assessed conditions. The results were comparable to those obtained in spinner culture of adherent Vero cells grown on Cytodex 1 microcarriers.Cell infection with LP-2061 rabies virus strain at an MOI (Multiplicity of Infection) of 0.1 and a cell density of 8 ± 0.5 × 105 cells/mL resulted in a virus titer higher than 107 FFU/mL in all media tested. Nevertheless, the highest titer equal to 5.2 ± 0.5 × 107 FFU/mL, was achieved in IPT-AFM containing a reduced amount of Ca++ and Mg++. Our results demonstrate the suitability of the obtained VeroS cells to produce rabies virus at a high titer, and pave the way to develop VeroS cells bioreactor process for rabies vaccine production. 相似文献
8.
Mengdie Jiang Bihan Wu Yongbing Sun Yanhuai Ding Yixi Xie 《Toxicology mechanisms and methods》2019,29(4):291-299
In a biological microenvironment, free fatty acids (FFA) as ubiquitous biological molecules might interact with nanoparticles (NPs) and consequently change the toxicological responses. However, whether the chemical structures of FFA could influence their interactions with NPs remain unknown. This study investigated the interactions between ZnO NPs and saturated or unsaturated FFA (complexed to BSA), namely stearic acid (SA, C18:0), oleic acid (OA, C18:1), and α-linolenic acid (ALA, C18:3). It was shown that BSA, SA, OA, and ALA increased the atomic force microscope (AFM) heights as well the polydispersity index (PDI) of ZnO NPs. BSA modestly protected THP-1 macrophages from ZnO NP exposure, whereas OA and ALA led to relatively less cyto-protective effects of BSA. Moreover, only co-exposure to ZnO NPs and SA significantly promoted the release of interleukin-8. BSA, SA, OA, and ALA equally changed intracellular ROS and Zn ions associated with ZnO exposure, but co-exposure to ZnO NPs and OA/ALA particularly activated the expression of endoplasmic reticulum stress-apoptosis genes. In combination, these results showed that FFA could influence the colloidal aspects and toxicological signaling pathway of ZnO NPs, which is dependent on the number of unsaturated bonds of FFA. 相似文献
9.
目的 探讨中性粒细胞与淋巴细胞比值(neutrophil to lymphocyte ratio,NLR)对三阴性乳腺癌的临床预后影响及与Ki - 67表达的关系。方法 回顾性分析2006年1月 - 2012年12月于我院乳腺外科住院治疗的134例三阴性乳腺癌患者。NLR最佳临床分界值采用ROC曲线确定,并依此分NLR<2.64组和NLR≥2.64组。临床独立预后因素采用单因素和多因素Cox回归模型分析。术后生存时间和生存曲线比较采用Kaplan - Meier和log - rank方法。Ki - 67的表达采用免疫组织化学方法检测。结果 NLR是三阴性乳腺癌的独立预后因素,最佳临界值为2.64。NLR<2.64组术后中位DFS为39.10月,中位OS为52.30月;NLR≥2.64组术后中位DFS为27.35月,中位OS为37.35月。2组术后DFS和OS比较,差异具有统计学意义(P<0.05)。NLR低组伴Ki - 67表达阴性的三阴性患者术后中位DFS和OS生存时间显著高于其他情况。结论 NLR是三阴性乳腺癌的关键影响预后因素,具有重复性强、非侵袭性、方便实用等特性,可用于预测三阴性乳腺癌临床预后。 相似文献
10.
化学药合成过程中水分残留不利于反应的进行,还影响药物及制剂的稳定性、理化性质、溶出及药理作用等,因此水分几乎是大多数药物合成中的必测项目,通过有效除水严格控制反应体系中水分的含量至关重要。本文综述了水分的存在形式,常见除水剂和脱水剂的种类、作用原理与除水能力,以及在药物合成的应用,为药物合成反应中水分的去除提供参考。 相似文献