Targeted Polymeric Micelle System for Delivery of Combretastatin A4 to Tumor Vasculature <Emphasis Type="Italic">In Vitro</Emphasis>

Purpose  

To develop an efficient tumor vasculature-targeted polymeric micelle delivery system for combretastatin A4 (CA4), a novel antivascular agent.     

17β-雌二醇-3位衍生物抗辐射活性研究

目的 研究新雌激素衍生物17β 雌二醇 3 烯丙基醚（ES 1）、17β 雌二醇 3 异戊烯基醚（ES 2）的抗辐射活性。方法以炔雌二醇和茜草双酯为阳性对照药,小鼠接受铯137（137Cs）γ 射线6.5 Gy一次性全身照射,观察各给药组白细胞数（WBC）、股骨有核细胞计数(BMNC)及DNA含量、脾结节数（CFU S）、脾指数、胸腺指数等相关指标变化。结果与对照组比较,ES 1和ES 2各给药剂量组小鼠在WBC、BMNC及DNA含量、CFU S、脾指数、胸腺指数均明显升高（P＜0.05或P＜0.01）,WBC变化非常明显,ES 1和ES 2两组均差异有极显著性（均P＜0.01）。结论ES 1、ES 2具有明显的抗辐射活性,有可能成为高效、低毒、口服的辐射防护药。     

Chimeric 5/35 adenovirus-mediated Dickkopf-1 overexpression suppressed tumorigenicity of CD44+ gastric cancer cells via attenuating Wnt signaling

Background

Gastric cancer stem cells (CSCs), which require activation of Wnt signaling to maintain their self-renewal and tumorigenicity, are proposed to be critical targets for effective therapy of gastric carcinomas. Gene therapies that are delivered by adenovirus of serotype 5 (Ad5) or chimeric 5/35(Ad5/35) adenovirus have shown promise for treating various cancers. Here we aimed to develop a gene therapy strategy that targeted gastric CSCs (CD44⁺ cells).

Methods

CD44⁺ cells were isolated by fluorescence activated cell sorting from both primary gastric cancer cells and cell lines. Expression of adenovirus receptors was examined in CD44⁺ and CD44^? cells. A potent Wnt antagonist Dickkopf-1 (DKK1) was delivered into CD44⁺ cells using Ad5/35 (Ad5/35-DKK1). The therapeutic outcomes were evaluated.

Results

Expression of Coxsakievirus adenovirus receptor for Ad5 was significantly reduced, while abundance of CD46, the receptor for Ad5/35, was slightly higher in CD44⁺ cells. Accordingly, CD44⁺ cells were sensitive to Ad5/35 infection, but not to Ad5. Ad5/35-DKK1 introduced DKK1 into CD44⁺ cells and deactivated endogenous Wnt/β-catenin signaling efficiently. Overexpression of DKK1 inhibited survival, anchorage-independent colony formation, and invasion of CD44⁺ cells, which were restored by a GSK-3 specific inhibitor BIO-acetoxime. More importantly, introduction of DKK1 abrogated the tumorigenicity of CD44⁺ cells in vivo. However, Ad5/35-DKK1 only showed minimal cytotoxicity to normal tissue-derived cells, L-02 and GES-1.

Conclusions

We developed, for the first time, a novel Ad5/35-DKK1-based approach to abrogate Wnt signaling in CSCs and demonstrated that gastric CSC-targeting gene therapy was effective in preclinical experiments.     

Effect of Phenylephrine on Alveolar Fluid Clearance in Ventilator-induced Lung Injury

Objective To investigate the effect of phenylephrine(an α-adrenergic agonist) on alveolar fluid clearance(AFC) in ventilator-induced lung injury and the possible mechanism involved.Methods A total of 170 male Wistar rats were randomly allocated into 17 groups(n=10) using random number tables.Short-term(40 minutes) mechanical ventilation with high tidal volume(HVT) was performed to induce lung injury,impair active Na + transport and lung liquid clearance in the rats.Unventilated rats served as controls.To demonstrate the effect of phenylephrine on AFC,phenylephrine at different concentrations(1×10-5,1×10-6,1×10-7,1×10-8,and 1×10-9 mol/L) was injected into the alveolar space of the HVT ventilated rats.To identify the influence of adrenergic antagonists,Na + channel,and microtubular system on the effect of phenylephrine,phenylephrine at 1×10-5 mol/L combined with prazosin(an α 1-adrenergic antagonist,1×10-4 mol/L),yohimbine(an α 2-adrenergic antagonist,1×10-4 mol/L),atenolol(a β 1 adrenergic antagonist,1×10-5 mol/L),ICI-118551(an β 2-adrenergic antagonist,1×10-5 mol/L),amiloride(a Na + channel blocker,5×10-4 mol/L),ouabain(a Na + /K +-ATPase blocker,5×10-4 mol/L),colchicine(a microtubular disrupting agent,0.25 mg/100 g body weight),or β-lumicolchicine(an isomer of colchicine,0.25 mg/100 g body weight) were perfused into the alveolar space of the rats ventilated with HVT for 40 minutes.AFC and total lung water content were measured.Results Basal AFC in control rats was(17.47±2.56)%/hour,which decreased to(9.64± 1.32)%/hour in HVT ventilated rats(P=0.003).The perfusion of phenylephrine at 1×10-8,1×10-7,1×10-6,and 1×10-5 mol/L significantly increased the AFC in HVT ventilated rats(all P<0.05).This effect of phenylephrine on AFC was suppressed by prazosin,atenolol,and ICI-118551 in HVT ventilated rats by 53%,31%,and 37%,respectively(all P<0.05).The AFC-stimulating effect of phenylephrine was lowered by 33% and 42% with amiloride and ouabain,respectively(both P<0.05).Colchicine significantly inhibited the effect of phenylephrine(P=0.031).Conclusion Phenylephrine could increase the AFC in HVT-ventilated rats and accelerate the absorption of pulmonary edema.     

正交试验优选制首乌水煎煮工艺

目的优选制首乌最佳水煎煮工艺。方法以制首乌的代表成分2,3,5,4′-四羟基-二苯乙烯-2-O-β-D-葡萄糖苷为评价指标,采用L9（34）正交试验设计、高效液相色谱法考察药材粒度、浸泡时间、煎煮时间、煎煮次数四个因素,对制首乌的水煎煮工艺进行优选。结果最佳水煎煮工艺：粒度为小块,浸泡30 min,煎煮时间70min,煎煮次数3次。结论优选所得的最佳煎煮工艺科学合理。     

Seroepidemiological Investigation of Lyme Disease and Human Granulocytic Anaplasmosis among People Living in Forest Areas of Eight Provinces in China

Objective Lyme disease and Human granulocytic anaplasmosis are tick‐borne diseases caused by Borrelia burgdorferi and Anaplasma phagocytophilum respectively. We have investigated infection and co-infection of the two diseases in the population of forest areas of eight provinces in China by measuring seroprevalence of antibodies against B. burgdorferi and A. phagocytophilum. Methods Forest areas in 8 provinces were chosen for investigation using whole sampling and questionnaire survey methods. 3 669 serum samples from people in the forest areas were tested for the presence of antibodies by indirect immunofluorescent assay (IFA). Results Seroprevalence against B. burgdorferi was 3% to 15% and against A. phagocytophilum was 2% to 18% in the study sites in the 8 provinces in China. We also found co-infection of B. burgdorferi and A. phagocytophilum in 7 of the 8 provinces (the exception being the Miyun area in Beijing). The seroprevalence for both B. burgdorferi and A. phagocytophilum was significantly higher among people exposed to ticks than among people who were not exposed to ticks. Conclusion We conclude that both pathogens are endemic in the forest areas in the eight provinces, but the prevalence of B. burgdorferi and A. phagocytophilum differs between the provinces.     

Emodin alleviates hypertrophic scar formation by suppressing macrophage polarization and inhibiting the Notch and TGF-β pathways in macrophages

Hypertrophic scar (HS) formation is a common complication that develops after skin injury; however, there are few effective and specific therapeutic approaches for HS. Emodin has previously been reported to inhibit mechanical stress-induced HS inflammation. Here, we investigated the molecular mechanisms underlying the inhibitory effects of emodin on HS formation. First, we conducted in vitro assays that revealed that emodin inhibited M1 and M2 polarization in rat macrophages. We subsequently established a combined rat model of tail HS and dorsal subcutaneous polyvinyl alcohol (PVA) sponge-induced wounds. Rats were treated with emodin or vehicle (DMEM). Tail scar specimens were harvested at 14, 28, and 42 days post-incision and subjected to H&E staining and Masson''s trichrome staining. Histopathological analyses confirmed that emodin attenuated HS formation and fibrosis. Macrophages were separated from wound cells collected from the PVA sponge at 3 and 7 days after implantation. Flow cytometry analysis demonstrated that emodin suppressed in vivo macrophage recruitment and polarization at the wound site. Finally, we explored the molecular mechanisms of emodin in modulating macrophage polarization by evaluating the expression levels of selected effectors of the Notch and TGF-β pathways in macrophages isolated from PVA sponges. Western blot and qPCR assays showed that Notch1, Notch4, Hes1, TGF-β, and Smad3 were downregulated in response to emodin treatment. Taken together, our findings suggested that emodin attenuated HS formation and fibrosis by suppressing macrophage polarization, which is associated with the inhibition of the Notch and TGF-β pathways in macrophages.     

降钙素原检测对脓毒症病情及预后判断的指导价值(附46例分析)

目的探讨血清降钙素原(PCT)检测对脓毒症病情及预后判断的指导价值。方法 46例脓毒症患者按病情轻重分早期脓毒症组、严重脓毒症组和脓毒症休克组,分别比较组间血清PCT、C反应蛋白(CRP)、WBC和急性生理与慢性健康状况评分(APACHEⅡ),并行PCT与APACHEⅡ评分相关性分析;同时按PCT水平,分为PCT<5.0、5.0～<10.0、PCT≥10.0ng/mL 3组,比较各组的病死率、抗生素使用时间、住院时间和外周血培养结果。结果脓毒症休克组与其他两组比较,PCT、CRP、WBC和APACHEⅡ评分差异均有统计学意义(P<0.05);严重脓毒症组与早期脓毒症组比较,PCT、CRP、APACHEⅡ差异有统计学意义(P<0.05),WBC差异无统计学意义(P>0.05),PCT与APACHEⅡ评分之间呈显著正相关(r=0.68,P<0.05);随着PCT水平升高,脓毒症患者病死率呈增高趋势,抗生素使用时间及住院时间延长(P<0.05),同时血培养阳性率升高。结论血PCT对脓毒症病情判断及评估预后有一定指导意义。     

对比评价紫檀芪和白藜芦醇的抗辐射活性

目的对比评价等摩尔当量紫檀芪和白藜芦醇对ICR小鼠的抗辐射作用。方法以6～8周龄ICR雄性小鼠为研究对象,给予6.5 Gyγ-射线一次性全身照射。空白照射组(给予0.5%羧甲基纤维素钠溶液),阳性对照组(给予茜草双酯100 mg.kg-1),白藜芦醇低、高剂量组(分别给予白藜芦醇50,150 mg.kg-1),紫檀芪低、高剂量组(分别给予紫檀芪56,168 mg.kg-1),均在照射前3 d内连续3次灌胃给药,照射后连续给予5 d,并在照射7 d后眼眶取血,解剖取胸腺、肝、脾、肺及两侧股骨。称重计算相关脏器系数,血清生化分析仪测白细胞计数(WBC)、血小板计数(PLT),以及股骨有核细胞(BMNC)和骨髓DNA,考察目标化合物紫檀芪和白藜芦醇的抗辐射损伤效应。结果与空白对照组比较,各实验组的各项指标均有所增加,且大部分差异有统计学意义(P<0.05),相同摩尔当量的紫檀芪实验组的抗辐射活性优于白藜芦醇组,尤其是紫檀芪低剂量组效果最佳,与白藜芦醇低剂量组比较差异有统计学意义(P<0.05)。结论紫檀芪对6.5Gy辐射损伤ICR小鼠的防护作用优于白藜芦醇,且紫檀芪低剂量组辐射防护效果最佳。     

RGD-modified polymeric micelles as potential carriers for targeted delivery to integrin-overexpressing tumor vasculature and tumor cells

Integrins αvβ3 and αvβ5 are overexpressed in angiogenic tumor endothelial cells and malignant tumor cells, making them attractive targets for cancer therapy. In this study, an integrin αvβ3 and αvβ5 binding tripeptide, RGD (Arg-Gly-Asp), was conjugated with the surface of poly(ethylene glycol)–block–poly(d,l-lactide) (PEG–PLA) micelles. A lipophilic fluorescent probe, DiI, was loaded into both the nontargeted methoxy PEG–PLA (mPEG–PLA) micelles and the targeted RGD-modified PEG–PLA micelles. The DiI-loaded targeted micelles had a size of 24.2?nm. The targeted micelles were stable in phosphate buffered saline and exhibited a negligible leakage in culture medium. Transmission electron microscopy analysis showed that targeted micelles were spherical in shape. Cell uptake of DiI-labeled targeted micelles by human umbilical vein endothelial cells and melanoma B16 cells was investigated by spectrophotofluorometry and confocal microscopy techniques. Results revealed that RGD-modified micelles significantly facilitated the intracellular delivery of the encapsulated agents via integrin-mediated endocytosis. This study suggests that RGD-modified PEG–PLA micelles are promising drug carriers for targeted delivery to both angiogenic tumor endothelial cells and tumor cells and that the targeted micelles may be attractive carriers for combination cancer therapy against both targets.