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Enhanced π-π Interactions Between a C_(60) Fullerene and a Buckle Bend on a Double-Walled Carbon Nanotube

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Nano Research 2010年第2期3卷 92-97页

作者： Sandeep Gorantla Stanislav Avdoshenko Felix Börrnert Alicja Bachmatiuk Maria Dimitrakopoulou Franziska Schäffel Ronny Schönfelder Jürgen thomas thomas Gemming Jamie HWarner Gianaurelio Cuniberti Jürgen Eckert Bernd Büchner Mark H.Rümmeli IFW Dresden P.O.Box 270116D-01171 DresdenGermany Institute for Materials Science and Max Bergmann Center of Biomaterials Dresden University of TechnologyDresden 01062Germany Department of Materials University of OxfordParks Rd.Oxford OX13PHUnited Kingdom

In situ low-voltage aberration corrected transmission electron microscopy(TEM)observations of the dynamic entrapment of a C_(60) molecule in the saddle of a bent double-walled carbon nanotube is *** fullerene interaction is non-covalent,suggesting that enhancedπ-πinteractions(van der Waals forces)are *** molecular dynamics calculations confirm that the increased interaction area associated with a buckle is sufficient to trap a ***,they show hopping behavior in agreement with our experimental *** findings further our understanding of carbon nanostructure interactions,which are important in the rapidly developing field of low-voltage aberration corrected TEM and nano-carbon device fabrication.

关键词： Carbon nanotubes fullerenes low-voltage transmission electron microscopy molecule trap

The hypoxia-inducible factor-1α activates ectopic production of fibroblast growth factor 23 in tumor-induced osteomalacia

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Bone Research 2016年第2期4卷 85-90页

作者： Qian Zhang Michele Doucet Ryan E Tomlinson Xiaobin Han L Darryl Quarles Michael T Collins thomas L Clemens Department of Orthopaedic Surgery Johns Hopkins University Baltimore MD USA Department of Medicine University of Tennessee Health Science Center Memphis TN USA Skeletal Clinical Studies Unit craniofacial and Skeletal Diseases Branch National Institutes of HealthBethesda MD USA Baltimore Veterans Administration Medical Center Baltimore MD USA

Tumor-induced osteomalacia （TIO） is a rare paraneoplastic syndrome in which ectopic production of fibroblast growth factor 23 （FGF23） by non-malignant mesenchymal tumors causes phosphate wasting and bone fractures. Recent studies have implicated the hypoxia-inducible factor-la （HIF-la） in other phosphate wasting disorders caused by elevated FGF23, including X-linked hypophosphatemic rickets and autosomal dominant hypophosphatemia. Here we provide evidence that HIF-la mediates aberrant FGF23 in TIO by transcriptionally activating its promoter. Immunohistochemical studies in phosphaturic mesenchymal tumors resected from patients with documented TIO showed that HIF-la and FGF23 were co-localized in spindle- shaped cells adjacent to blood vessels. Cultured tumor tissue produced high levels of intact FGF23 and demonstrated increased expression of HIF-la protein. Transfection of mc3T3-E1 and Saos-2 cells with a HIF-la expression construct induced the activity of a FGF23 reporter construct. Prior treatment of tumor organ cultures with HIF-la inhibitors decreased HIF-la and FGF23 protein accumulation and inhibited HIF-la-induced luciferase reporter activity in transfected cells. Chromatin immunoprecipitation assays confirmed binding to a HIF-la consensus sequence within the proximal FGF23 promoter, which was eliminated by treatment with a HIF-la inhibitor. These results show for the first time that HIF-la is a direct transcriptional activator of FGF23 and suggest that upregulation of HIF-la activity in TIO contributes to the aberrant FGF23 production in these patients.

关键词： The hypoxia-inducible factor-1 activates ectopic production of fibroblast growth factor 23 in tumor-induced osteomalacia HIF

Resolving impact volatilization and condensation from target rock mixing and hydrothermal overprinting within the Chicxulub impact structure

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Geoscience Frontiers 2022年第5期13卷 16-31页

作者： thomas Déhais Stepan M.Chernonozhkin Pim Kaskes Sietze J.de Graaff Vinciane Debaille Frank Vanhaecke Philippe Claeys Steven Goderis Analytical Environmental and Geo-ChemistryVrije Universiteit BrusselBrusselsBelgium Laboratoire G-Time UniversitécLibre de BruxellesBrusselsBelgium Department of Chemistry Atomic&Mass SpectrometryGhent UniversityGhentBelgium

This work presents isotopic data for the non-traditional isotope systems Fe,Cu,and Zn on a set of Chicxulub impactites and target lithologies with the aim of better documenting the dynamic processes taking place during hypervelocity impact events,as well as those affecting impact structures during the post-impact *** focus lies on material from the recent IODP-ICDP Expedition 364 Hole M0077A drill core obtained from the offshore Chicxulub peak *** ejecta blanket samples from the UNAM 5 and 7 cores were used to compare the crater lithologies with those outside of the impact *** datasets of bulk Fe,Cu,and Zn isotope ratios are coupled with petrographic observations and bulk major and trace element compositions to disentangle equilibrium isotope fractionation effects from kinetic *** observed Fe and Cu isotopic signatures,with δ^(56/54)Fe ranging from0.95‰to 0.58‰and δ^(65/63)Cu from0.73‰to 0.14‰,mostly reflect felsic,mafic,and carbonate target lithology mixing and secondary sulfide mineral formation,the latter associated to the extensive and long-lived(>105 years)hydrothermal system within Chicxulub *** the other hand,the stable Zn isotope ratios provide evidence for volatility-governed isotopic *** heavier Zn isotopic compositions observed for the uppermost part of the impactite sequence and a metamorphic clast(δ^(66/64)Zn of up to 0.80‰and 0.87‰,respectively)relative to most basement lithologies and impact melt rock units indicate partial vaporization of Zn,comparable to what has been observed for Cretaceous-Paleogene boundary layer sediments around the world,as well as for tektites from various strewn *** contrast to previous work,our data indicate that an isotopically light Zn reservoir(δ^(66/64)Zn down to0.49‰),of which the existence has previously been suggested based on mass balance considerations,may reside within the upper impact melt rock(UIM)*** observation is restricted to a few UIM sampl

关键词： Chicxulub impact structure Non-traditional stable isotopes Impact volatilization Impact condensation Hydrothermal alteration Target lithology mixing

氢化物发生-多接收杯电感耦合等离子体质谱同位素稀释法测定硒同位素

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分析化学 2008年第10期36卷 1385-1390页

作者：朱建明 Johnson thomas M Clark Scott K 朱祥坤环境地球化学国家重点实验室中国科学院地球化学研究所 Department of Geology 245 NHBUniversity of Illinois at Urbana-Champaign 国土资源部同位素地质重点实验室中国地质科学院地质研究所

使用改进的巯基棉分离流程和74硒-77硒双稀释剂,在氢化物(HG)-多接收器电感耦合等离子体质谱仪(mc-ICP-MS)实现了高精度硒同位素组成的测定。巯基棉用于分离样品基质中的硒,随后使用HNO3+H2O2消除干扰的有机质,74硒-77硒双稀释剂校正样... 详细信息

使用改进的巯基棉分离流程和74硒-77硒双稀释剂,在氢化物(HG)-多接收器电感耦合等离子体质谱仪(mc-ICP-MS)实现了高精度硒同位素组成的测定。巯基棉用于分离样品基质中的硒,随后使用HNO3+H2O2消除干扰的有机质,74硒-77硒双稀释剂校正样品分离和质谱测定过程中的硒同位素质量分馏。硒标准溶液NISTSRM3149和MH495几个月的测定表明,该方法的外精度为0.1‰(2σ),样品的外精度为0.15‰～0.2‰(2σ)。以TCF分离硒的平均回收率85%计算,最小硒需要量为20ng。实验结果以相对于NISTSRM3149的δ82/76Se表达,δM82H/74965/SRM3149=-3.44±0.1‰(2σ),优于已发表的数据δ8M2H/74965/SRM3149=-3.04±0.5‰。测定样品的δ8S2R/M736149为-13.53‰～11.37‰,为硒同位素在环境、农业、生命和地球科学中的拓展应用与发展奠定了基础。

关键词：硒同位素同位素稀释剂巯基棉氢化物发生多接受杯电感耦合等离子体质谱仪

Interpatient heterogeneity in hepatic microvascular blood flow during vascular inflow occlusion (Pringle manoeuvre)

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Hepatobiliary Surgery and Nutrition 2020年第3期9卷 271-283页

作者： Lucinda Shen Zühre Uz Joanne Verheij Denise P.Veelo Yasin Ince Can Ince thomas M.van Gulik Department of Translational Physiology Amsterdam UMCLocation Academic Medical CenterUniversity of AmsterdamAmsterdamThe Netherlands Department of Intensive Care Laboratory of Translational Intensive CareErasmus MCUniversity Medical CenterRotterdamThe Netherlands Department of Surgery Amsterdam UMCLocation Academic Medical CenterUniversity of AmsterdamAmsterdamThe Netherlands Department of Pathology Amsterdam UMCLocation Academic Medical CenterUniversity of AmsterdamAmsterdamThe Netherlands Department of Anesthesiology Amsterdam UMCLocation Academic Medical CenterUniversity of AmsterdamAmsterdamThe Netherlands

Background:Vascular inflow occlusion(VIO)during liver resections(Pringle manoeuvre)can be applied to reduce blood loss,however may at the same time,give rise to ischemia-reperfusion injury(IRI).The aim of this study was to assess the characteristics of hepatic microvascular perfusion during VIO in patients undergoing major liver ***:Assessment of hepatic microcirculation was performed using a handheld vital microscope(HVM)at the beginning of surgery,end of VIO(20 minutes)and during reperfusion after the termination of *** microcirculatory parameters assessed were:functional capillary density(FCD),microvascular flow index(MFI)and sinusoidal diameter(SinD).Results:A total of 15 patients underwent VIO;8 patients showed hepatic microvascular perfusion despite VIO(partial responders)and 7 patients showed complete cessation of hepatic microvascular perfusion(full responders).Functional microvascular parameters and blood flow levels were significantly higher in the partial responders when compared to the full responders during VIO(FCD:0.84±0.88 vs.0.00±0.00 mm/mm2,P<0.03,respectively,and MFI:0.69–0.22 vs.0.00±0.00,P<0.01,respectively).Conclusions:An interpatient heterogeneous response in hepatic microvascular blood flow was observed upon *** may explain why clinical strategies to protect the liver against IRI lacked consistency.

关键词： Liver perfusion microcirculation

mcC1019,a selective inhibitor of the Polo-box domain of Polo-like kinase 1 as novel,potent anticancer candidate

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Acta Pharmaceutica Sinica B 2019年第5期9卷 1021-1034页

作者： Sara Abdelfatah Angela Berg Qi Huang Li Jun Yang Sami Hamdoun Anette Klinger Henry J.Greten Edmond Fleischer Thorsten Berg Vincent K.W.Wong thomas Efferth Department of Pharmaceutical Biology Institute of Pharmacy and BiochemistryJohannes Gutenberg UniversityMainz55128Germany Leipzig University Institute of Organic ChemistryLeipzig04103Germany State Key Laboratory of Quality Research in Chinese Medicine Macao University of Science and TechnologyMacaoChina MicroCombiChem GmbH Wiesbaden65203Germany Abel Salazar Institute of Biomedical Sciences University of PortoPorto4099-003Portugal

Polo-like kinase(PLK1) has been identified as a potential target for cancer *** a number of small molecules have been investigated as PLK1 inhibitors, many of which showed limited selectivity. PLK1 harbors a regulatory domain, the Polo box domain(PBD), which has a key regulatory function for kinase activity and substrate recognition. We report on 3-bromomethylbenzofuran-2-carboxylic acid ethyl ester(designated: mcC1019) as selective PLK1 inhibitor targeting PLK1 PBD. Cytotoxicity and fluorescence polarization-based screening were applied to a library of 1162 drug-like compounds to identify potential inhibitors of PLK1 PBD. The activity of compound mc1019 against the PLK1 PBD was confirmed using fluorescence polarization and microscale *** compound exerted specificity towards PLK1 over PLK2 and PLK3. mcC1019 showed cytotoxic activity in a panel of different cancer cell lines. Mechanistic investigations in A549 lung adenocarcinoma cells revealed that mcC1019 induced cell growth inhibition through inactivation of AKT signaling pathway, it also induced prolonged mitotic arrest—a phenomenon known as mitotic catastrophe, which is followed by immediate cell death via apoptosis and necroptosis. mcC1019 significantly inhibited tumor growth in vivo in a murine lung cancer model without affecting body weight or vital organ size, and reduced the growth of metastatic lesions in the lung. We propose mcC1019 as promising anti-cancer drug candidate.

关键词： Polo-like kinase PLK1 Polo box domain Mono-targeted therapy Cell cycle Necroptosis Spindle damage

Establishing a standard method for analysing case detection delay in leprosy using a Bayesian modelling approach

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Infectious Diseases of Poverty 2023年第1期12卷 71-81页

作者： thomas Hambridge Luc E.Coffeng Sake J.de Vlas Jan Hendrik Richardus Department of Public Health Erasmus MCUniversity Medical Center RotterdamRotterdamThe Netherlands

Background Leprosy is an infectious disease caused by Mycobacterium leprae and remains a source of preventable disability if left *** detection delay is an important epidemiological indicator for progress in interrupting transmission and preventing disability in a ***,no standard method exists to effectively analyse and interpret this type of *** this study,we aim to evaluate the characteristics of leprosy case detection delay data and select an appropriate model for the variability of detection delays based on the best fitting distribution *** Two sets of leprosy case detection delay data were evaluated:a cohort of 181 patients from the post exposure prophylaxis for leprosy(PEP4LEP)study in high endemic districts of Ethiopia,Mozambique,and Tanzania;and self-reported delays from 87 individuals in 8 low endemic countries collected as part of a systematic literature *** models were fit to each dataset to assess which probability distribution(log-normal,gamma or Weibull)best describes variation in observed case detection delays using leave-one-out cross-validation,and to estimate the effects of individual *** For both datasets,detection delays were best described with a log-normal distribution combined with covariates age,sex and leprosy subtype[expected log predictive density(ELPD)for the joint model:-1123.9].Patients with multibacillary(MB)leprosy experienced longer delays compared to paucibacillary(PB)leprosy,with a relative difference of 1.57[95%Bayesian credible interval(BCI):1.14-2.15].Those in the PEP4LEP cohort had 1.51(95%BCI:1.08-2.13)times longer case detection delay compared to the self-reported patient delays in the systematic *** The log-normal model presented here could be used to compare leprosy case detection delay datasets,including PEP4LEP where the primary outcome measure is reduction in case detection *** recommend the application of this modelling approach to test d

关键词： Leprosy Case detection delay Neglected tropical diseases Epidemiological methods Bayesian approach Statistical model

Evaluation of Thermal-Aware Design Techniques for Microprocessors

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Evaluation of Thermal-Aware Design Techniques for Microproce...

Pre-osteoblastic mc3T3-E1 cells promote breast cancer growth in bone in a murine xenograft model

2005 6th International Conference on ASIC

作者： thomas D.Richardson Yuan Xie Computer Science and Engineering Department The Pennsylvania State University USA

＜正＞As technology scales,temperature in modern highperformance VLSI circuits has increased *** affects not only the performance but also the power, reliability,and cost of the *** this paper,we examine two approaches to reduce the on-chip temperature:one is to reduce the power densities of hot functional units by allocating more die area（growing units）,and the other one is to use three different migrating computation（mc） techniques to migrate activities among duplicated functional *** the use of tools for architectural power and temperature estimation,the effectiveness of these two methods are evaluated for the Alpha 21264 microprocessor.

关键词： Microprocessors Temperature Thermal management Power system reliability Electronic packaging thermal management Microarchitecture Costs Modems Energy consumption Knowledge management

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Chinese Journal of Cancer 2011年第3期30卷 189-196页

作者： thomas M. Bodenstine Benjamin H. Beck Xuemei Cao Leah M. Cook Aimen Ismail J. Kent Powers Andrea M. Mastro Danny R. Welch Department of Pathology University of Alabama at Birmingham Birmingham AL 35294 USA National Foundation for Cancer Research-Center for Metastasis Research University of Alabama at Birmingham Birmingham AL 35294 USA Department of Biochemistry and Molecular Biology Pennsylvania State University University Park PA 16802 USA Department of Pharmacology/ Toxicology University of Alabama at Birmingham Birmingham AL 35294 USA Cell Biology University of Alabama at Birmingham Birmingham AL 35294 USA Comprehensive Cancer Center University of Alabama at Birmingham Birmingham AL 35294 USA Center for Metabolic Bone Disease University of Alabama at Birmingham Birmingham AL 35294 USA.

The bones are the most common sites of breast cancer metastasis. Upon arrival within the bone microenvironment, breast cancer cells coordinate the activities of stromal cells, resulting in an increase in osteoclast activity and bone matrix degradation. In late stages of bone metastasis, breast cancer cells induce apoptosis in osteoblasts, which further exacerbates bone loss. However, in early stages, breast cancer cells induce osteoblasts to secrete inflammatory cytokines purported to drive tumor progression. To more thoroughly evaluate the role of osteoblasts in early stages of breast cancer metastasis to the bones, we used green fluorescent protein-labeled human breast cancer cell lines MDA-MB-231 and MDA-MB-435, which both induce osteolysis after intra-femoral injection in athymic mice, and the murine pre-osteoblastic cell line mc3T3-E1 to modulate osteoblast populations at the sites of breast cancer metastasis. Breast cancer cells were injected directly into the femur with or without equal numbers of mc3T3-E1 cells. Tumors grew significantly larger when co-injected with breast cancer cells and mc3T3-E1 cells than injected with breast cancer cells alone. Osteolysis was induced in both groups, indicating that mc3T3-E1 cells did not block the ability of breast cancer cells to cause bone destruction. mc3T3-E1 cells promoted tumor growth out of the bone into the extraosseous stroma. These data suggest that breast cancer cells and osteoblasts communicate during early stages of bone metastasis and promote tumor growth.

关键词：乳腺癌细胞成骨细胞肿瘤生长小鼠绿色荧光蛋白标记模型移植早期阶段