Chloroquine interferes with dengue‐2 virus replication in U937 cells

The objective of this study was to investigate the use of chloroquine (CLQ) as an antiviral agent against dengue. Chloroquine, an amine acidotropic drug known to affect intracellular exocytic pathways by increasing endosomal pH, was used in the in vitro treatment of U937 cells infected with dengue virus type 2 (DENV‐2). Viral replication was assessed by quantification of virus produced through detection of copy numbers of DENV‐2 RNA, plaque assay and indirect immunofluorescence. qRT‐PCR and plaque assays were used to quantify the DENV‐2 load in infected U937 cells after CLQ treatment. It was found that a dose of 50 μg/mL of CLQ was not toxic to the cells and resulted in significantly less virus production in infected U937 cells than occurred in untreated cells. In the present work, CLQ was effective against DENV‐2 replication in U937 cells, and also caused a statistically significant reduction in expression of proinflammatory cytokines. The present study indicates that CLQ may be used to reduce viral yield in U937 cells.     

湿地植物根表铁膜研究进展

为了适应渍水环境,许多湿地植物都具有根系泌氧、形成铁膜的能力。因铁膜具有特殊的物理或化学结构,可以通过吸附和共沉淀作用影响元素在土壤中的化学行为和生物有效性,在植物吸收营养元素和重金属中起重要作用。综述了湿地植物根表铁膜的形成、影响因素以及根表铁膜对营养元素和重金属的生态环境效应,从表征技术方面阐述了根表铁膜的作用机制。对今后的研究方向给出如下建议:(1)扩大研究领域;(2)铁膜形成的动态变化过程;(3)铁膜对植物生理形态的影响;(4)利用先进的表征技术以确定铁膜的作用机制。     

比较两种测量方法获得的血压波动对老年颈动脉斑块的影响

目的:比较两种不同血压波动测定方法测定的血压波动与颈动脉斑块发生的关系。方法:以1456名患有动脉硬化老年男性患者为研究对象,监测患者24 h动态血压,根据有无颈动脉斑块将入选患者分为2组:颈动脉斑块组(n=1012)和无颈动脉斑块组(n=444),分别采用经典的标准差方法(SD法)和个体血压波动测定方法(个体法)分别测定每位患者的血压波动,回顾性分析这两种方法测定的血压波动与颈动脉斑块形成的关联性。结果:SD法测定颈动脉斑块组24 h收缩期血压波动(SBPV)、白天SBPV、夜间SBPV以及24 h舒张期血压波动(DBPV)水平均明显高于无颈动脉斑块组(P0.05);而白天和夜间DBPV差异无统计学意义。个体法测定颈动脉斑块组24 h SBPV、白天SBPV、24 h DBPV以及白天DBPV水平较无颈动脉斑块组均明显升高(P0.05);夜间SBPV和夜间DBPV差异无统计学意义(P0.05)。比较颈动脉斑块组SBPV值出现次数,SD法测定SBPV最多的是10-15 mmHg(n=541),其次是大于15 mmHg(n=399);个体法测定颈动脉斑块组SBPV值出现次数最多的是0-8 mmHg(n=490),其次是8-10 mmHg(n=350)。结论:在老年男性动脉硬化相关疾病患者中,血压波动与颈动脉斑块的形成有着密切的关系,两种方法均可测定血压波动,但以个体血压波动测定方法更加敏感。     

他克莫司和卡泊三醇软膏治疗四肢斑块状银屑病的疗效和安全性分析

目的:探讨他克莫司和卡泊三醇软膏治疗四肢斑块状银屑病的疗效和安全性。方法:选取2011年4月至2013年8月于我院诊治的84例四肢斑块状银屑病患者,将患者随机分为A组和B组,每组各42例,分别采用他克莫司和卡泊三醇软膏治疗。评定PASI以及疗效指数,并对用药过程中患者的不良事件进行观察记录。结果:A、B两组患者治疗后各时间点PASI评分与治疗前相比较均显著降低,差异有统计学意义(P0.05);但同一时间组间对比,差异并无统计学意义(P0.05)。A组银屑病患者的总有效率为64.29%,与B组的69.05%相比,差异无统计学意义(P0.05)。结论:他克莫司与卡泊三醇软膏治疗四肢斑块状银屑病均安全有效,且二药相比,疗效相当。     

Mechanical action of the blood onto atheromatous plaques: influence of the stenosis shape and morphology

The vulnerability of atheromatous plaques in the carotid artery may be related to several factors, the most important being the degree of severity of the endoluminal stenosis and the thickness of the fibrous cap. It has recently been shown that the plaque length can also affect the mechanical response significantly. However, in their study on the effect of the plaque length, the authors did not consider the variations of the plaque morphology and the shape irregularities that may exist independently of the plaque length. These aspects are developed in this paper. The mechanical interactions between the blood flow and an atheromatous plaque are studied through a numerical model considering fluid–structure interaction. The simulation is achieved using the arbitrary Lagrangian–Eulerian scheme in the COMSOL TM commercial finite element package. The stenosis severity and the plaque length are, respectively, set to 45% and 15 mm. Different shapes of the stenosis are modelled, considering irregularities made of several bumps over the plaque. The resulting flow patterns, wall shear stresses, plaque deformations and stresses in the fibrous cap reveal that the effects of the blood flow are amplified if the slope upstream stenosis is steep or if the plaque morphology is irregular with bumps. More specifically, the maximum stress in the fibrous cap is 50% larger for a steep slope than for a gentle slope. These results offer new perspectives for considering the shape of plaques in the evaluation of the vulnerability.     

A distinct subfraction of Aβ is responsible for the high‐affinity Pittsburgh compound B‐binding site in Alzheimer's disease brain

The positron emission tomography (PET) ligand ¹¹C‐labeled Pittsburgh compound B (PIB) is used to image β‐amyloid (Aβ) deposits in the brains of living subjects with the intent of detecting early stages of Alzheimer's disease (AD). However, deposits of human‐sequence Aβ in amyloid precursor protein transgenic mice and non‐human primates bind very little PIB. The high stoichiometry of PIB:Aβ binding in human AD suggests that the PIB‐binding site may represent a particularly pathogenic entity and/or report local pathologic conditions. In this study, ³H‐PIB was employed to track purification of the PIB‐binding site in > 90% yield from frontal cortical tissue of autopsy‐diagnosed AD subjects. The purified PIB‐binding site comprises a distinct, highly insoluble subfraction of the Aβ in AD brain with low buoyant density because of the sodium dodecyl sulfate‐resistant association with a limited subset of brain proteins and lipids with physical properties similar to lipid rafts and to a ganglioside:Aβ complex in AD and Down syndrome brain. Both the protein and lipid components are required for PIB binding. Elucidation of human‐specific biological components and pathways will be important in guiding improvement of the animal models for AD and in identifying new potential therapeutic avenues.

     

Clinical value of plasma pentraxin 3 levels for predicting cardiac troponin elevation after percutaneous coronary intervention

Aims

Post-procedural myocardial necrosis manifested by elevated cardiac troponin T (cTnT) often complicates percutaneous coronary intervention (PCI). Plasma pentraxin 3 (PTX3) levels are increased in patients with arterial inflammation and especially unstable angina pectoris (UAP). This study tested whether plasma PTX3 levels can predict post-PCI cTnT elevation.

Main methods

We evaluated 94 consecutive patients with AP and normal pre-PCI cTnT levels who underwent PCI. Pre-PCI virtual histology-intravascular ultrasound was performed to assess culprit plaque composition. Plasma PTX3 and serum hs-CRP levels were measured pre-PCI. Patients were divided into 2 groups according to presence (Group I, n = 34) or absence (Group II, n = 60) of post-PCI cTnT elevation > 3 × the upper limit of normal at 24 h after PCI.

Key findings

Plasma PTX3 (4.06 ± 2.05 ng/ml vs 2.17 ± 1.02 ng/ml, p < 0.001), serum hs-CRP levels (0.25 ± 0.03 vs 0.16 ± 0.03 mg/dl, p = 0.048), plaque burden (80.9 ± 5.3 vs 75.4 ± 10.6%, p = 0.047), presence of positive remodeling (59 vs 25%, p = 0.034), and percent necrotic core area (19.0 ± 7.4 vs 14.0 ± 5.9%, p = 0.046) were significantly higher in Group I than in Group II. Receiver-operating characteristic curve analysis showed that with a best cut-off value of 2.83 ng/ml, plasma PTX3 level (AUC 0.823) predicted post-PCI cardiac TnT elevation better than did serum hs-CRP level (AUC 0.618). Multiple logistic regression analysis showed that plasma PTX3 level was the most independent predictor of post-PCI cardiac cTnT elevation (OR: 2.65; 95% CI: 1.56–10.1; p = 0.003).

Significance

Plasma PTX3 level may be a useful marker for predicting post-PCI cardiac cTnT elevation, which is associated with inflammatory status of culprit lesions.     

High-dose of vitamin C supplementation reduces amyloid plaque burden and ameliorates pathological changes in the brain of 5XFAD mice

Blood–brain barrier (BBB) breakdown and mitochondrial dysfunction have been implicated in the pathogenesis of Alzheimer''s disease (AD), a neurodegenerative disease characterized by cognitive deficits and neuronal loss. Besides vitamin C being as one of the important antioxidants, recently, it has also been reported as a modulator of BBB integrity and mitochondria morphology. Plasma levels of vitamin C are decreased in AD patients, which can affect disease progression. However, investigation using animal models on the role of vitamin C in the AD pathogenesis has been hampered because rodents produce with no dependence on external supply. Therefore, to identify the pathogenic importance of vitamin C in an AD mouse model, we cross-bred 5 familial Alzheimer''s disease mutation (5XFAD) mice (AD mouse model) with ι-gulono-γ-lactone oxidase (Gulo) knockout (KO) mice, which are unable to synthesize their own vitamin C, and produced Gulo KO mice with 5XFAD mice background (KO-Tg). These mice were maintained on either low (0.66 g/l) or high (3.3 g/l) supplementation of vitamin C. We found that the higher supplementation of vitamin C had reduced amyloid plaque burden in the cortex and hippocampus in KO-Tg mice, resulting in amelioration of BBB disruption and mitochondrial alteration. These results suggest that intake of a larger amount of vitamin C could be protective against AD-like pathologies.     

不同栽培方式对籼、粳稻根表铁膜和根铁、镉含量的影响

在Cd污染土壤中研究淹水、覆膜、覆草和湿润栽培对籼、梗稻不同生育时期根表铁膜Fe、Cd含量和根Cd含量的影响．结果表明,在分蘖期,梗稻根表铁膜Fe含量和根Cd含量在4种栽培方式中平均为6．37和25．49mg．kg^-1。分别比籼稻的4．52和16．37mg·kg^-1增加1．85和9．12mg·kg^-1．在孕穗期,粳稻根表铁膜Fe、Cd含量和根Cd含量在4种栽培方式中平均为1．60、16．35和54．68mg·kg^-1,分别比籼稻的1．06、9．56kg和43．31mg·kg^-1增加0．54、6．79和11．37mg·kg^-1．在灌浆期,梗稻根表铁膜Fe含量覆草和湿润栽培为0．89和1．00mg·kg^-1,分别比籼稻的0．63和0．30mg·kg^-1增加0．26和0．70mg·kg^-1;梗稻根表铁膜Cd和根Cd含量在4种栽培方式中平均为15．23和73．68mg·kg^-1,分别比籼稻的3．46和52．38mg·kg^-1增加11．77和21．30mg·kg^-1收获时。根表铁膜Fe含量淹水栽培的籼稻为1．21mg·g^-1,比梗稻的0．65mg·g^-1增加0．56mg·g^-1,覆草栽培的梗稻为0．94mg·g^-1,比籼稻0．55mg·g^-1增加0．39mg·g^-1;根表铁膜Cd含量湿润栽培的梗稻为7．96mg·kg^-1,比籼稻的5．09mg·kg^-1增加2．87mg·kg^-1;根Cd含量梗稻在4种栽培方式中平均为54．53mg·kg^-1,比籼稻的35．91mg·kg^-1增加18．62mg·kg^-1。