Protein binding of salicylate in cutaneous hepatic porphyria

Summary (1) Plasma protein binding of salicylate was studied in 14 patients with cutaneous hepatic porphyria (CHP) and 11 normal subjects using ultrafiltration with centrifugation (membrane cones) and continuous ultrafiltration. (2) Albumin and haemoglobin levels were significantly reduced in patients with CHP, and salicylate binding by ultrafiltration/centrifugation was 65% compared with 84% in normal subjects. (3) Plasma porphyrin levels were raised, but did not correlate with salicylate binding, and protoporphyrin or uroporphyrin added to plasma did not alter the amount of drug bound. (4) Palmitate added to plasma reduced salicylate binding by 9 to 20% but a crossover of patient and normal plasma proteins and ultrafiltrates confirmed that no other ultrafiltrable metabolites present in patient plasma appeared to cause decreased binding. (5) Scatchard plots obtained by continuous ultrafiltration for normal and patient plasma showed a reduction in the number of primary and secondary binding sites and an increase in the intrinsic association constants for both these sites. (6) It was concluded that the decreased salicylate binding in CHP was due to a reduced albumin concentration and altered salicylate albumin interaction.     

蛋白质膳食管理对腹膜透析病人血浆蛋白的影响

目的:探讨蛋白质膳食管理对腹膜透析病人血浆蛋白的影响。方法:随机抽取在我院进行腹膜透析的社保病人40例,并将其随机分为实验组和对照组,实验组除进行口头宣教外,还根据病人体重、饮食习惯,制定具体的蛋白质摄入方案;对照组则只进行口头宣教。实施管理后每月复查血浆蛋白。结果:实施蛋白质膳食管理10个月后,实验组第1个月和第2个月病人的总蛋白值和白蛋白值与管理前相比较没有统计学意义(P>0.05),从第3个月起病人的总蛋白值和白蛋白值与管理前相比较有统计学意义(P<0.05),而其球蛋白值在管理前后的差异均没有统计学意义(P>0.05);对照组病人的总蛋白值、白蛋白值和球蛋白值在管理前后的差异均没有统计学意义(P>0.05)。结论:对腹膜透析病人实行长期的蛋白质膳食管理可有效提高病人的血浆蛋白。     

A fluorescent curcumin-based Zn(II)-complex reactivates mutant (R175H and R273H) p53 in cancer cells

Background

Mutations of the p53 oncosuppressor gene are amongst the most frequent aberration seen in human cancer. Some mutant (mt) p53 proteins are prone to loss of Zn(II) ion that is bound to the wild-type (wt) core, promoting protein aggregation and therefore unfolding. Misfolded p53 protein conformation impairs wtp53-DNA binding and transactivation activities, favouring tumor growth and resistance to antitumor therapies. Screening studies, devoted to identify small molecules that reactivate mtp53, represent therefore an attractive anti-cancer therapeutic strategy. Here we tested a novel fluorescent curcumin-based Zn(II)-complex (Zn-curc) to evaluate its effect on mtp53 reactivation in cancer cells.

Methods

P53 protein conformation was examined after Zn-curc treatment by immunoprecipitation and immunofluorescence assays, using conformation-specific antibodies. The mtp53 reactivation was evaluated by chromatin-immunoprecipitation (ChIP) and semi-quantitative RT-PCR analyses of wild-type p53 target genes. The intratumoral Zn-curc localization was evaluated by immunofluorescence analysis of glioblastoma tissues of an ortothopic mice model.

Results

The Zn-curc complex induced conformational change in p53-R175H and -R273H mutant proteins, two of the most common p53 mutations. Zn-curc treatment restored wtp53-DNA binding and transactivation functions and induced apoptotic cell death. In vivo studies showed that the Zn-curc complex reached glioblastoma tissues of an ortothopic mice model, highlighting its ability to crossed the blood-tumor barrier.

Conclusions

Our results demonstrate that Zn-curc complex may reactivate specific mtp53 proteins and that may cross the blood-tumor barrier, becoming a promising compound for the development of drugs to halt tumor growth.     

P38信号通路与糖尿病特有因素关系的探讨

目的：探讨P38信号通路(P38MAPK)在糖尿病大血管并发症中的作用。方法：分别以糖尿病特有因素：高葡萄糖、糖基化终产物(AGEs)、高胰岛素和过氧化氢刺激人脐静脉内皮细胞(HUVECs)，观察HUVECs P38MAPK磷酸化蛋白表达。结果：高葡萄糖、AGES、高胰岛素和过氧化氢均可做为独立因素激活P38MAPK，使其磷酸化表达量增加。结论：高葡萄糖、AGES生成增多、高胰岛素和氧化应激是糖尿病患者合并大血管并发症的易患因素；P38MAPK可能在糖尿病大血管并发症的发生、发展中起关键作用。     

双向电泳质谱法研究女性肺腺癌转移淋巴结的蛋白表达

目的:分析肺腺癌转移淋巴结与正常淋巴结组织蛋白质表达差异.方法:运用蛋白质组技术,对肺腺癌转移淋巴结与正常淋巴结组织蛋白质进行分离和比较分析,并在蛋白质和mRNA水平进行进一步验证.结果:获得了背景清晰、分辨率和重复性较好的双向凝胶电泳图谱,比较分析显示与正常淋巴结蛋白质表达水平相比,肺腺癌转移淋巴结有23个蛋白点的表达量存在明显差异.其中新增蛋白点4个,缺失1个,14个蛋白点表达水平明显上调,4个蛋白点表达水平明显下调.共鉴定了11个肺癌转移相关蛋白,其中,候选蛋白膜联蛋白1(ANX1)、细胞骨架蛋白(CK18)、Rho-GDP解离抑制剂1(GDIR)、原肌球蛋白3(TPMF)、蛋白谷氨酰胺γ-谷氨酰转移酶(TGLC)和白介素18(IL-18)在肺腺癌转移淋巴结显著低表达,而候选蛋白核氯离子通道蛋白1(CLI1)、蛋白质二硫键异构酶(ER60)、肌酸激酶、硫氧还蛋白过氧化物酶1(PDX1)和热休克蛋白60(CH60)在肺腺癌转移淋巴结表达水平比正常淋巴结明显提高.结论:肺腺癌转移淋巴结与正常淋巴结蛋白质表达存在明显差异,这11种蛋白质可能与肺腺癌淋巴结转移机制有关.     

蛋白激酶C亚型在血管外膜成纤维细胞中的表达

目的了解蛋白激酶C（PKC）亚型在血管外膜成纤维细胞中的表达情况。方法用β1-转化生长因子（TGF-1β）可将AF诱导为MF,用免疫组化法可以鉴定转化是否成功。根据文献报道,蛋白激酶C的许多亚型在AF与MF中的表达量往往差异有统计学意义。实验选取PKC-ε、PKC-δ、PKC-ζ作为研究对象用定量PCR的方法,比较它们在AF和MF中表达的差异。结果 PKC-ε、PKC-ζ的表达在MF中明显高于AF,而PKC-δ的表达差异无统计学意义。结论本实验为进一步研究PKC家族在血管外膜成纤维细胞表型转化中的作用打下基础。     

应用蛋白质芯片技术筛选直肠癌患者

目的应用表面增强激光解吸电离飞行时间质谱技术(SELDI-TOF-MS)从直肠癌患者血清中筛选标志蛋白,找出最佳的标志蛋白组合模式作为临床诊断指标。方法采用WCX2芯片及SELDI-TOF-MS技术对98例直肠癌患者及40例对照组血清进行蛋白质指纹图谱检测分析,所得到的结果采用Biomarker Wizard和Biomarker Patterns System软件分析。结果直肠癌组与对照组共有26个蛋白质差异有显著性(P<0.05);以其中4个蛋白质生物标志物(质/荷比9295、3730、3938和4095)组建筛选模型,经盲法验证,其敏感度为95.0%(57/60),特异性为93.4%(45/48);CEA敏感度为68.3%(41/60),特异性为77.1%(37/48);CA199敏感度为58.3%(35/60),特异性为75%(36/48)。结论SELDI-TOF-MS技术的敏感度和特异性远远高于目前所采用的某一单独的标志物的血清学诊断,其结果对进一步研究直肠癌的蛋白质组学改变及其临床应用可能具有重要意义。     

单核细胞趋化蛋白-1在系膜增生性肾小球肾炎中的表达

目的用免疫组化的方法来分析单核细胞趋化蛋白-1在系膜增生性肾小球肾炎中表达的变化规律,揭示单核细胞趋化蛋白-1是否可做为病理条件下系膜细胞增生程度评判的一项指标。方法应用链霉素抗卵白素一过氧化酶连接法（S—P法）检测正常肾组织、42例轻至重度系膜增生性肾小球肾炎肾组织标本肾小球区单核细胞趋化蛋白-1表达的相对面积的变化。利用HPIAS—1000采集的图像对肾小球区的阳性表达区域所占相对面积进行测算。结果在正常肾组织切片中,仅部分肾小球内系膜细胞、肾小管上皮细胞及灶件炎细胞浸润区域单核细胞趋化蛋白-1阳性表达,绝大多数没有表达,染色阴性。不同程度增生肾小球区单核细胞趋化蛋白-1表达的相对面积不同,单核细胞趋化蛋白-1阳性表达的相对面积随系膜增生病变程度加重而增加,存在统计学差异。结论单核细胞趋化蛋白-1在肾小球区的表达随系膜增生病变程度加重而增加。在不同病变程度系膜增生性肾小球肾炎的肾小管、间质存在强、弱不等的表达。正常肾组织中,仅有少量单核细胞趋化蛋白-1表达。     

Mutational Analysis of Triple-Negative Breast Cancer Using Targeted Kinome Sequencing

PurposeTriple-negative breast cancer (TNBC) does not have defined therapeutic targets and is currently treated with chemotherapy only. Kinase dysregulation triggers cancer cell proliferation and metastasis and is a crucial therapeutic target for cancer. In this study, targeted kinome sequencing of TNBC tumors was performed to assess the association between kinome gene alterations and disease outcomes in TNBC.MethodsA kinome gene panel consisting of 612 genes was used for the targeted sequencing of 166 TNBC samples and matched normal tissues. Analyses of the significantly mutated genes were performed. Genomic differences between Asian and non-Asian patients with TNBC were evaluated using two Asian TNBC datasets (from Seoul National University Hospital [SNUH] and Fudan University Shanghai Cancer Center [FUSCC]) and three non-Asian TNBC datasets (The Cancer Genome Atlas [TCGA], METABRIC, and Gustave Roussy). The prognostic value of kinome gene mutations was evaluated using tumor mutational burden (TMB) and oncogenic pathway analyses. Mutational profiles from the TCGA were used for validation.ResultsThe significantly mutated genes included TP53 (60% of patients), PIK3CA (21%), BRCA2 (8%), and ATM (8%). Compared with data from non-Asian public databases, the mutation rates of PIK3CA p.H1047R/Q were significantly higher in the SNUH cohort (p = 0.003, 0.048, and 0.032, respectively). This was verified using the FUSCC dataset (p = 0.003, 0.078, and 0.05, respectively). The TMB-high group showed a trend toward longer progression-free survival in our cohort and the TCGA TNBC cohort (p = 0.041 and 0.195, respectively). Kinome gene alterations in the Wnt pathway in patients with TNBC were associated with poor survival in both datasets (p = 0.002 and 0.003, respectively).ConclusionComprehensive analyses of kinome gene alterations in TNBC revealed genomic alterations that offer therapeutic targets and should help identify high-risk patients more precisely in future studies.     

PDX-1蛋白对棕榈酸诱导的大鼠胰岛凋亡的保护作用

目的探讨PDX-1蛋白对棕榈酸诱导的大鼠胰岛凋亡的保护作用。方法PDX-1基因克隆及表达质粒的构建,PDX-1蛋白的表达、纯化和鉴定,PDX-1蛋白保护棕榈酸引起的胰岛细胞凋亡的研究。结果PDX-1蛋白可以延缓胰岛细胞的自然凋亡过程,保护其三维形态;可以降低处理后的胰岛Caspase-3活性,同时可以增加葡萄糖刺激胰岛素释放,PDX-1蛋白干预后的棕榈酸组（1.560±0.074）uIU/mL,与对照组（1.426±0.056）uIU/mL相比有显著差异（P〈0.05）。结论表明PDX-1蛋白可以减少棕榈酸诱导的胰岛凋亡,保护β细胞功能。