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《Vaccine》2020,38(13):2859-2869
To examine the link between meningococcal C (MenC) vaccine size and immunogenic response, a panel of MenC glycoconjugate vaccines were prepared differing in chain length, molar mass and hydrodynamic volume. The preparations consisted of different lengths of MenC polysaccharide (PS) covalently linked to monomeric purified tetanus toxoid (TT) carrier protein using the coupling reagent ethylcarbodiimide hydrochloride (EDC). Size exclusion chromatography with multi-angle light scattering (SEC-MALS) and viscometry analysis confirmed that the panel of MenC-TT conjugates spanned masses of 191,500 to 2,348,000 g/mol, and hydrodynamic radii ranging from 12.1 to 47.9 nm. The two largest conjugates were elliptical in shape, whereas the two smallest conjugates were more spherical. The larger conjugates appeared to fit a model described by multiple TTs with cross-linked PS, typical of lattice-like networks described previously for TT conjugates, while the smaller conjugates were found to fit a monomeric or dimeric TT configuration. The effect of vaccine conjugate size on immune responses was determined using a two-dose murine immunization. The two larger panel vaccine conjugates produced higher anti-MenC IgG1 and IgG2b titres after the second dose. Larger vaccine conjugate size also stimulated greater T-cell proliferative responses in an in vitro recall assay, although cytokines indicative of a T-helper response were not measurable. In conclusion, larger MenC-TT conjugates up to 2,348,000 g/mol produced by EDC chemistry correlate with greater humoral and cellular murine immune responses. These observations suggest that conjugate size can be an important modulator of immune response. 相似文献
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目的:观察健脾疏肝降脂方治疗非酒精性脂肪肝(NAFLD)肥胖小鼠ALT、AST、FFA及光镜下病理组织学改变,并与壳脂胶囊治疗组比较,观察其疗效。方法:将72只小鼠随机分为模型组、健脾疏肝降脂方高、中、低剂量组、壳脂胶囊对照组和空白组。采用饲养高脂饲料及皮下注射5%CCl4复制NAFLD肥胖小鼠模型,分别以相应药物灌胃6周,检测血清中ALT、AST及FFA的含量,光镜下观察肝组织的脂肪变程度。结果:①各个用药组相比模型组,血清ALT、AST均降低有统计学意义(P<0.01),且中药各浓度组较壳脂胶囊组血清ALT、AST降低,差异有统计学意义(P<0.05); 中药高、中剂量组相比模型组FFA降低,比较有统计学意义(P<0.05); 但与壳脂胶囊组相比,中药各剂量组改善FFA,差异无明显统计学意义(P>0.05)。②光镜可见:各用药组光镜下病理组织改变均较模型组明显,以中、高剂量组较低剂量组小鼠肝细胞脂肪变程度减轻较明显。结论:健脾疏肝降脂方能有效降低NAFLD肥胖小鼠的肝功能、其与浓度无关; 可以降低FFA及改善光镜下肝脏的脂肪变,其有效程度与浓度有一定的关系。 相似文献
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《药学学报(英文版)》2020,10(8):1453-1475
Angiokinases, such as vascular endothelial-, fibroblast- and platelet-derived growth factor receptors (VEGFRs, FGFRs and PDGFRs) play crucial roles in tumor angiogenesis. Anti-angiogenesis therapy using multi-angiokinase inhibitor has achieved great success in recent years. In this study, we presented the design, synthesis, target identification, molecular mechanism, pharmacodynamics (PD) and pharmacokinetics (PK) research of a novel triple-angiokinase inhibitor WXFL-152. WXFL-152, identified from a series of 4-oxyquinoline derivatives based on a structure–activity relationship study, inhibited the proliferation of vascular endothelial cells (ECs) and pericytes by blocking the angiokinase signals VEGF/VEGFR2, FGF/FGFRs and PDGF/PDGFRβ simultaneously in vitro. Significant anticancer effects of WXFL-152 were confirmed in multiple preclinical tumor xenograft models, including a patient-derived tumor xenograft (PDX) model. Pharmacokinetic studies of WXFL-152 demonstrated high favourable bioavailability with single-dose and continuous multi-dose by oral administration in rats and beagles. In conclusion, WXFL-152, which is currently in phase Ib clinical trials, is a novel and effective triple-angiokinase inhibitor with clear PD and PK in tumor therapy. 相似文献
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Shahrzad Ghafary Roshanak Ghobadian Mohammad Mahdavi Hamid Nadri Alireza Moradi Tahmineh Akbarzadeh Zahra Najafi Mohammad Sharifzadeh Najmeh Edraki Farshad Homayouni Moghadam Mohsen Amini 《Daru : journal of Faculty of Pharmacy, Tehran University of Medical Sciences》2020,28(2):463
BackgroundAcetylcholine deficiencies in hippocampus and cortex, aggregation of β-amyloid, and β-secretase over activity have been introduced as main reasons in pathogenesis of Alzheimer’s disease.MethodsColorimetric Ellman’s method was used for determination of IC50 value in AChE and BChE inhibitory activity. The kinetic studies, neuroprotective and β-secretase inhibitory activities, evaluation of inhibitory potency on β-amyloid (Aβ) aggregations induced by AChE, and docking study were performed for prediction of the mechanism of action.Result and discussionA new series of cinnamic acids-tryptamine hybrid was designed, synthesized, and evaluated as dual cholinesterase inhibitors. These compounds demonstrated in-vitro inhibitory activities against acetyl cholinesterase (AChE) and butyryl cholinesterase (BChE). Among of these synthesized compounds, (E)-N-(2-(1H-indol-3-yl)ethyl)-3-(3,4-dimethoxyphenyl)acrylamide (5q) demonstrated the most potent AChE inhibitory activity (IC50 = 11.51 μM) and (E)-N-(2-(1H-indol-3-yl)ethyl)-3-(2-chlorophenyl)acrylamide (5b) were the best anti-BChE (IC50 = 1.95 μM) compounds. In addition, the molecular modeling and kinetic studies depicted 5q and 5b were mixed type inhibitor and bound with both the peripheral anionic site (PAS) and catalytic sites (CAS) of AChE and BChE. Moreover, compound 5q showed mild neuroprotective in PC12 cell line and weak β-secretase inhibitory activities. This compound also inhibited aggregation of β-amyloid (Aβ) in self-induced peptide aggregation test at concentration of 10 μM.ConclusionIt is worth noting that both the kinetic study and the molecular modeling of 5q and 5b depicted that these compounds simultaneously interacted with both the catalytic active site and the peripheral anionic site of AChE and BChE. These findings match with those resulted data from the enzyme inhibition assay. Graphical abstractOpen in a separate windowA new series of cinnamic-derived acids-tryptamine hybrid derivatives were designed, synthesized and evaluated as butyrylcholinesterase (BChE) and acetylcholinesterase (AChE) inhibitors and neuroprotective agents. Compound 5b and 5q, as the more potent compounds, interacted with both the peripheral site and the choline binding site having mixed type inhibition. Results suggested that derivatives have a therapeutic potential for the treatment of AD.Electronic supplementary materialThe online version of this article (10.1007/s40199-020-00346-9) contains supplementary material, which is available to authorized users. 相似文献
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Carmen Cuffari Steven L Ciciora Masakazu Ando Mena Boules Joseph M Croffie 《World journal of gastroenterology : WJG》2020,26(40):6260-6269
BACKGROUND Bowel preparation in children can be challenging.AIM To describe the efficacy, safety, and tolerability of sodium picosulfate, magnesium oxide, and citric acid(SPMC) bowel preparation in children.METHODS Phase 3, randomized, assessor-blinded, multicenter study of low-volume, divided dose SPMC enrolled children 9-16 years undergoing elective colonoscopy. Participants 9-12 years were randomized 1:1:1 to SPMC ? dose × 2, SPMC 1 dose × 2, or polyethylene glycol(PEG). Participants 13-16 years were randomized 1:1 to SPMC 1 dose × 2 or PEG. PEG-based bowel preparations were administered per local protocol. Primary efficacy endpoint for quality of bowel preparation was responders(rating of ‘excellent' or ‘good') by modified Aronchick Scale. Secondary efficacy endpoint was participant's tolerability and satisfaction from a 7-item questionnaire. Safety assessments included adverse events(AEs) and laboratory evaluations.RESULTS 78 participants were randomized, 48 were 9-12 years, 30 were 13-16 years. For the primary efficacy endpoint in 9-12 years, 50.0%, 87.5%, and 81.3% were responders for SPMC ? dose × 2, SPMC 1 dose × 2, and PEG groups, respectively. Responder rates for 13-16 years were 81.3% for SPMC 1 dose × 2 and 85.7% for PEG. Overall, 43.8% of participants receiving SPMC 1 dose × 2 reported it was ‘very easy' or ‘easy' to drink, compared with 20.0% receiving PEG. Treatment-emergent AEs were reported by 45.5% of participants receiving SPMC 1 dose × 2 and 63.0% receiving PEG.CONCLUSION SPMC was an efficacious and safe for bowel preparation in children 9-16 years, with comparable efficacy to PEG. Tolerability for SPMC was higher compared to PEG. 相似文献
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