Ablation of Breast Cancer Cells Using Trastuzumab‐Functionalized Multi‐Walled Carbon Nanotubes and Trastuzumab‐Diphtheria Toxin Conjugate

Trastuzumab (Herceptin^®) is a monoclonal antibody (mAb) for specific ablation of HER2‐overexpressing malignant breast cancer cells. Intensification of antiproliferative activity of trastuzumab through construction of immunotoxins and nano‐immunoconjugates is a promising approach for treatment of cancer. In this study, trastuzumab was directly conjugated to diphtheria toxin (DT). Also, conjugates of trastuzumab and multiwalled carbon nanotubes (MWCNT) were constructed by covalent immobilization of trastuzumab onto MWCNTs. Then, antiproliferative activity of the fusion constructs against HER2‐overexpressing SK‐BR‐3 and also HER2‐negative MCF‐7 cancer cell lines were examined. Cells treated with trastuzumab‐MWCNT conjugates were irradiated with near‐infrared (NIR) light. Efficient absorption of NIR radiation and its conversion to heat by MWCNTs can be resulted to thermal ablation of cancerous cells. Our results strongly showed that both trastuzumab‐MWCNT and trastuzumab‐DT conjugates were significantly efficient in the specific killing of SK‐BR‐3 cells. Targeting of MWCNTs to cancerous cells using trastuzumab followed by exposure of cells to NIR radiation was more efficient in repression of cell proliferation than treatment for cancer cells with trastuzumab‐DT. Our results also showed that conjugation linkers can significantly affect the cytotoxicity of MWCNT‐immunoconjugates. In conclusion, our data demonstrated that trastuzumab‐MWCNT is a promising nano‐immunoconjugate for killing of HER2‐overexpressing cancerous cells.     

骨碎补总黄酮联合纳米骨材料促进MC3T3-E1细胞的增殖分化

文题释义： 骨碎补总黄酮：是由水龙骨科植物槲蕨的干燥根茎中提取的有效成分,骨碎补总黄酮能够促进成骨细胞增殖,抑制破骨细胞成熟分化。 Wnt/β-catenin信号通路：是一类高度保守的信号通路,广泛存在于多细胞真核生物中,是皮肤发育过程中出现最早的分子信号,调控毛囊的生长发育和毛囊干细胞的迁移分化。β-catenin作为细胞内信号传导蛋白,是Wnt信号通路激活的一种重要的上皮细胞表面黏附分子,能够进入细胞核内传递Wnt信号,进一步激活靶基因开始转录,启动细胞增殖周期。 背景：前期研究发现,骨碎补总黄酮可促进纳米骨材料表面MC3T3-E1细胞的成骨分化,其作用机制有待进一步研究。 目的：探究骨碎补总黄酮联合纳米骨材料对MC3T3-E1细胞发挥作用的机制。 方法：将MC3T3-E1细胞与纳米骨材料共培养,选取100 mg/L和250 mg/L骨碎补总黄酮进行药物干预,以10 μg/L转化生长因子β刺激为阳性对照组。分组如下：①正常组;②DKK1组：Wnt通路抑制剂DKK1      (0.1 mg/L)阻断Wnt/β-catenin信号通路;③DKK1+转化生长因子β组;④DKK1+100 mg/L骨碎补总黄酮组;⑤DKK1+250 mg/L骨碎补总黄酮组;⑥DKK1+纳米骨+转化生长因子β组;⑦DKK1+纳米骨+100 mg/L骨碎补总黄酮组;⑧DKK1+纳米骨+250 mg/L骨碎补总黄酮组。在干预24,48 h后收获细胞,免疫荧光双染法观察Wnt/β-catenin通路中Wnt与LRP结合情况,Real-time PCR和Western blot检测β-catenin、LRP5、Gsk-3β、Cyclin D1、RUNX2的表达。 结果与结论：①激光共聚焦扫描显微镜下显示DKK1+转化生长因子β组、DKK1+250 mg/L骨碎补总黄酮组、DKK1+纳米骨+转化生长因子β组、DKK1+纳米骨+250 mg/L骨碎补总黄酮组棕黄色染色较明显,表明Wnt与LRP结合较其他组更好;②Real-time PCR和Western blot结果显示,骨碎补总黄酮可促进β-catenin、LRP5、RUNX2的表达,下调GSK-3β的表达,说明骨碎补总黄酮通过激活经典Wnt/β-catenin 信号通路促进成骨细胞增殖分化,且骨碎补总黄酮诱导的基因活化呈剂量依赖性。 ORCID: 0000-0002-2031-8644(李晋玉) 中国组织工程研究杂志出版内容重点：干细胞;骨髓干细胞;造血干细胞;脂肪干细胞;肿瘤干细胞;胚胎干细胞;脐带脐血干细胞;干细胞诱导;干细胞分化;组织工程     

Epicardial delivery of collagen patches with adipose-derived stem cells in rat and minipig models of chronic myocardial infarction

Although transplantation of adipose-derived stem cells (ADSC) in chronic myocardial infarction (MI) models is associated with functional improvement, its therapeutic value is limited due to poor long-term cell engraftment and survival. Thus, the objective of this study was to examine whether transplantation of collagen patches seeded with ADSC could enhance cell engraftment and improve cardiac function in models of chronic MI. With that purpose, chronically infarcted Sprague–Dawley rats (n = 58) were divided into four groups and transplanted with media, collagen scaffold (CS), rat ADSC, or CS seeded with rat ADSC (CS-rADSC). Cell engraftment, histological changes, and cardiac function were assessed 4 months after transplantation. In addition, Göttingen minipigs (n = 18) were subjected to MI and then transplanted 2 months later with CS or CS seeded with autologous minipig ADSC (CS-pADSC). Functional and histological assessments were performed 3 months post-transplantation. Transplantation of CS-rADSC was associated with increased cell engraftment, significant improvement in cardiac function, myocardial remodeling, and revascularization. Moreover, transplantation of CS-pADSC in the pre-clinical swine model improved cardiac function and was associated with decreased fibrosis and increased vasculogenesis. In summary, transplantation of CS-ADSC resulted in enhanced cell engraftment and was associated with a significant improvement in cardiac function and myocardial remodeling.     

Risk factors for carbapenem-resistant Klebsiella pneumoniae bloodstream infection among rectal carriers: a prospective observational multicentre study

Knowledge of carbapenem-resistant Klebsiella pneumoniae (CR-KP) colonization is important to prevent nosocomial spread but also to start prompt adequate antibiotic therapy in patients with suspicion of infection. However, few studies have examined the incidence and risk factors for CR-KP bloodstream infection (BSI) among rectal carriers. To identify risk factors for CR-KP BSI among carriers, we performed a multicentre prospective matched case–control study of all adult CR-KP rectal carriers hospitalized in five tertiary teaching hospitals in Italy over a 2-year period. Carriers who developed CR-KP BSI were compared with those who did not develop subsequent BSI. Overall, 143 CR-KP BSIs were compared with 572 controls without a documented infection during their hospitalization. Multivariate analysis revealed that admission to the Intensive Care Unit (ICU) (OR, 1.65; 95% CI, 1.05–2.59; p 0.03), abdominal invasive procedure (OR, 1.87; 95% CI, 1.16–3.04; p 0.01), chemotherapy/radiation therapy (OR, 3.07; 95% CI, 1.78–5.29; p <0.0001), and number of additional colonization sites (OR, 3.37 per site; 95% CI, 2.56–4.43; p <0.0001) were independent risk factors for CR-KP BSI development among CR-KP rectal carriers. A CR-KP BSI risk score ranging from 0 to 28 was developed based on these four independent variables. At a cut-off of ≥2 the model exhibited a sensitivity, specificity, positive predictive value and negative predictive value of 93%, 42%, 29% and 93%, respectively. Colonization at multiple sites with CR-KP was the strongest predictor of BSI development in our large cohort of CR-KP rectal carriers.     

Fecal carriage and molecular epidemiologic characteristics of carbapenemase-producing Enterobacterales in primary care hospital in a Japanese city

BackgroundThe worldwide spread of organisms with antimicrobial resistance is of concern, especially the trend of significantly increasing carbapenemase-producing Enterobacterales (CPE). In this study, we investigated the annual trend of intestinal CPE carriage rates in inpatients and healthy adults in a primary care hospital in Tenri, Japan.MethodsWe collected 551 samples of feces from inpatients in our institution and 936 samples from healthy people living in Tenri city from December 2012 to April 2015. All samples were cultured on MacConkey agar plates containing 4 μg/mL ceftazidime for screening test. The colonies grown on the screening medium were detected for carbapenemase genes (bla_IMP-1, bla_IMP-2, bla_VIM, bla_KPC, bla_GES, bla_NDM, and bla_OXA-48 groups) by multiplex PCR, and CPE were identified by MALDI-TOF MS. Plasmid replicon typing and pulsed-field gel electrophoresis (PFGE) were performed on PCR-positive strains.ResultsThe CPE carriage rate was 1.6% (9/551) in the inpatient group and 0% (0/936) in the healthy adults group. The numbers of strains positive for the carbapenemase gene were 4 for Enterobacter cloacae, 2 for Klebsiella pneumoniae, 1 for Citrobacter freundii, 1 for Raoultella ornithinolytica and 1 for Escherichia coli. In all CPE strains, the carbapenemase gene was bla _IMP-6 and the plasmid replicon type was IncN. The 4 E. cloacae strains showed a similar pattern in PFGE.ConclusionIn the same city in Japan, CPE intestinal carriers were detected only in the inpatient group in this study but not in a healthy adults, suggesting that the spread of asymptomatic CPE carriers was confined to inpatients.     

Sleep disturbances in asymptomatic BRCA1/2 mutation carriers: women at high risk for breast–ovarian cancer

This study investigated the association between positive genetic diagnosis for BRCA1/2 mutations and sleep quality in Ashkenazi asymptomatic women. Seventy‐three women, including 17 asymptomatic BRCA1/2 carriers and 20 non‐carriers from the oncogenetic clinic, and 36 community controls, participated in a cross‐sectional design. Women completed sociodemographic, clinical, general psychological distress, cancer‐related worry (CRW), fatigue and sleep questionnaires in their homes, and wore actigraphs for 5–7 nights. Impaired global subjective sleep quality was demonstrated in BRCA1/2 carriers compared to non‐carriers and controls [mean Pittsburgh sleep quality index (PSQI) total scores 7.29 ± 4.34; 3.94 ± 2.49; 4.21 ± 2.80, respectively, P = 0.021] and poor sleep quality (PSQI total score >5) was significantly higher in carriers (53%) compared to non‐carriers (20%) and controls (28%, P = 0.03). Based on actigraphic measures, sleep latency tended to be longer in carriers compared to counterparts, albeit not significantly. Increased sleep disturbance was related significantly to increased fatigue in the entire sample and in the control group; to psychological distress in the entire sample and in non‐carriers; and to CRW in the entire sample. In carriers, sleep disturbance was related strongly but non‐significantly to fatigue, psychological distress and CRW. Fatigue and carrier status were significant predictors of sleep quality, accounting for 15.7% of the variance. In conclusion, asymptomatic BRCA1/2 carriers experience poor sleep quality compared to non‐carriers and controls. Our study design is unique in that it offers insight regarding the nature of being an asymptomatic carrier, and affords the opportunity to examine factors that may contribute to the development of insomnia in women at risk for breast–ovarian cancer.     

西罗莫司纳米脂质载体固化制剂的制备

采用冷冻干燥法以微晶纤维素Avicel PH-101与聚乙烯吡咯烷酮(PVP)K30的混合物(4:1,w,%)为吸附性粉末固化西罗莫司纳米脂质载体分散液,并以再分散时间、平均粒径及分布、流动性和泄漏率等为指标,采用单因素试验优化固化处方。结果表明,3批按优化方法制备的西罗莫司纳米脂质载体固化制剂的休止角为(42.65±0.80)。,振实密度为(0.79±0.03)g/m1,且含量均匀度良好,再分散时间为(10.0±0.4)min,再分散液粒径(132.7+2.6)nm,分布系数0.297±0.01,ξ电位(-12.8±1.05)mV,冻干前后的泄漏率为(10.80±0.41)%。     

新型纳米结构脂质载体系统的研究进展

目的介绍新型的纳米结构脂质载体系统的研究进展,为其研究和应用提供参考。方法查阅相关文献33篇,进行整理和归纳。结果新型的纳米结构脂质载体能够克服固体脂质纳米粒的一些不足,并具有独特的结构特征,药物的包封机理和释放特征。结论纳米结构脂质载体作为药物传递系统的一种新剂型,具有广阔的发展前景。     

壳聚糖衍生物——N-三甲基壳聚糖的促吸收作用研究进展

目的:探讨壳聚糖衍生物——N-三甲基壳聚糖促吸收作用的研究进展。方法:查阅国内外有关N-三甲基壳聚糖促吸收作用的机制、影响因素及应用的文献,并进行分析、总结。结果:N-三甲基壳聚糖可增加细胞旁路途径的跨膜转运,具有促进药物吸收的作用。结论:N-三甲基壳聚糖有望作为一种有效促吸收剂应用于药物制剂。     

无症状乙肝病毒携带者心理健康状况调查与分析

目的:探讨慢性乙型肝炎病毒(HBV)携带者的心理健康状况及其影响因素. 方法:采用自编一般情况问卷和症状自评量表SCL-90式对300例传染科门诊就诊的携带乙肝病毒的患者进行调查.结果:①SCL-90结果显示:心理问题的总检出率为26%.AsC患者各因子均分明显高于全国常模(P<0.001).在各因子中,尤其以躯体化、焦虑、敌对和精神病为重.②不同性别、婚姻状况、医疗方式、受教育程度、病程之间各因子分均有差异(P<0.05),其中自费者、农民、已婚患者的心理问题较重.结论:无症状慢性HBV携带者心理健康状况较差.