Loss of epithelial markers and acquisition of vimentin expression in adriamycin- and vinblastine-resistant human breast cancer cell lines

We have previously observed that breast cancer cell lines could exhibit either epithelial or fibroblastic phenotypes as reflected by their morphologies and intermediate filament protein expression (C. L. Sommers, D. Walker-Jones, S. E. Heckford, P. Worland, E. Valverius, R. Clark, M. Stampfer, and E. P. Gelmann, Cancer Res., 49: 4258-4263, 1989). Fibroblastoid, vimentin-expressing breast cancer cell lines are more invasive in vitro and in vivo (E. W. Thompson, S. Paik, N. Brunner, C. L. Sommers, G. Zugmaier, R. Clarke, T. B. Shima, J. Torri, S. Donahue, M. E. Lippman, G. R. Martin, and R. B. Dickson, J. Cell. Physiol., 150: 534-544, 1992). We hypothesized that a breast cancer cell with an epithelial phenotype could undergo a transition to a fibroblastic phenotype, possibly resulting in more invasive capacity. We now show that two Adriamycin-resistant MCF-7 cell lines and a vinblastine-resistant ZR-75-B cell line have undergone such a transition. Adriamycin-resistant MCF-7 cells express vimentin, have diminished keratin 19 expression, have lost cell adhesion molecule uvomorulin expression, and have reduced formation of desmosomes and tight junctions as determined by reduced immunodetection of their components desmoplakins I and II and zonula occludens (ZO)-1. Other MCF-7 cell lines selected for resistance to vinblastine and to Adriamycin and verapamil did not have these characteristics, indicating that drug selection does not invariably cause these phenotypic changes. In addition, to determine if vimentin expression in MCF-7 cells alone could manifest a fibroblastic phenotype, we transfected the full-length human vimentin complementary DNA into MCF-7 cells. Although vimentin expression was achieved in MCF-7 cells, it did not affect the phenotype of the cells in terms of the distribution of keratins, desmoplakins I and II, ZO-1, or uvomorulin or in terms of in vitro invasiveness. We conclude that vimentin expression is a marker for a fibroblastic and invasive phenotype in breast cancer cells but does not by itself give rise to this phenotype.

A dynamic in vivo model of epithelial-to-mesenchymal transitions in circulating tumor cells and metastases of breast cancer

Epithelial-to-mesenchymal transition (EMT) processes endow epithelial cells with enhanced migratory/invasive properties and are therefore likely to contribute to tumor invasion and metastatic spread. Because of the difficulty in following EMT processes in human tumors, we have developed and characterized an animal model with transplantable human breast tumor cells (MDA-MB-468) uniquely showing spontaneous EMT events to occur. Using vimentin as a marker of EMT, heterogeneity was revealed in the primary MDA-MB-468 xenografts with vimentin-negative and vimentin-positive areas, as also observed on clinical human invasive breast tumor specimens. Reverse transcriptase-PCR after microdissection of these populations from the xenografts revealed EMT traits in the vimentin-positive zones characterized by enhanced 'mesenchymal gene' expression (Snail, Slug and fibroblast-specific protein-1) and diminished expression of epithelial molecules (E-cadherin, ZO-3 and JAM-A). Circulating tumor cells (CTCs) were detected in the blood as soon as 8 days after s.c. injection, and lung metastases developed in all animals injected as examined by in vivo imaging analyses and histology. High levels of vimentin RNA were detected in CTCs by reverse transcriptase-quantitative PCR as well as, to a lesser extent, Snail and Slug RNA. Von Willebrand Factor/vimentin double immunostainings further showed that tumor cells in vascular tumoral emboli all expressed vimentin. Tumoral emboli in the lungs also expressed vimentin whereas macrometastases displayed heterogenous vimentin expression, as seen in the primary xenografts. In conclusion, our data uniquely demonstrate in an in vivo context that EMT occurs in the primary tumors, and associates with an enhanced ability to intravasate and generate CTCs. They further suggest that mesenchymal-to-epithelial phenomena occur in secondary organs, facilitating the metastatic growth.

A Bruch’s membrane substitute fabricated from silk fibroin supports the function of retinal pigment epithelial cells in vitro

Silk fibroin provides a promising biomaterial for ocular tissue reconstruction including the damaged outer blood-retinal barrier of patients afflicted with age-related macular degeneration (AMD). The aim of the present study was to evaluate the function of retinal pigment epithelial (RPE) cells in vitro, when grown on fibroin membranes manufactured to a similar thickness as Bruch’s membrane (3 μm). Confluent cultures of RPE cells (ARPE-19) were established on fibroin membranes and maintained under conditions designed to promote maturation over 4 months. Control cultures were grown on polyester cell culture well inserts (Transwell). Cultures established on either material developed a cobblestoned morphology with partial pigmentation within 12 weeks. Immunocytochemistry at 16 weeks revealed a similar distribution pattern between cultures for F-actin, ZO-1, ezrin, cytokeratin pair 8/18, RPE-65 and Na+/K+-ATPase. Electron microscopy revealed that cultures grown on fibroin displayed a rounder apical surface with a more dense distribution of microvilli. Both cultures avidly ingested fluorescent microspheres coated with vitronectin and bovine serum albumin (BSA), but not controls coated with BSA alone. VEGF and PEDF were detected in the conditioned medium collected from above and below both membrane types. Levels of PEDF were significantly higher than for VEGF on both membranes and a trend was observed towards larger amounts of PEDF in apical compartments. These findings demonstrate that RPE cell functions on fibroin membranes are equivalent to those observed for standard test materials (polyester membranes). As such, these studies support advancement to studies of RPE cell implantation on fibroin membranes in a preclinical model.

Where and how to conserve: Extending the scope of spatial reserve network design

Ongoing habitat loss and fragmentation threaten much of the biodiversity that we know today. As such, conservation efforts are required if we want to protect biodiversity. Conservation budgets are typically tight, making the cost-effective selection of protected areas difficult. Therefore, reserve design methods have been developed to identify sets of sites, that together represent the species of conservation interest in a cost-effective manner. To be able to select reserve networks, data on species distributions is needed. Such data is often incomplete, but species habitat distribution models (SHDMs) can be used to link the occurrence of the species at the surveyed sites to the environmental conditions at these locations (e.g. climatic, vegetation and soil conditions). The probability of the species occurring at unvisited location is next predicted by the model, based on the environmental conditions of those sites. The spatial configuration of reserve networks is important, because habitat loss around reserves can influence the persistence of species inside the network. Since species differ in their requirements for network configuration, the spatial cohesion of networks needs to be species-specific. A way to account for species-specific requirements is to use spatial variables in SHDMs. Spatial SHDMs allow the evaluation of the effect of reserve network configuration on the probability of occurrence of the species inside the network. Even though reserves are important for conservation, they are not the only option available to conservation planners. To enhance or maintain habitat quality, restoration or maintenance measures are sometimes required. As a result, the number of conservation options per site increases. Currently available reserve selection tools do however not offer the ability to handle multiple, alternative options per site. This thesis extends the existing methodology for reserve design, by offering methods to identify cost-effective conservation planning solutions when multiple, alternative conservation options are available per site. Although restoration and maintenance measures are beneficial to certain species, they can be harmful to other species with different requirements. This introduces trade-offs between species when identifying which conservation action is best applied to which site. The thesis describes how the strength of such trade-offs can be identified, which is useful for assessing consequences of conservation decisions regarding species priorities and budget. Furthermore, the results of the thesis indicate that spatial SHDMs can be successfully used to account for species-specific requirements for spatial cohesion - in the reserve selection (single-option) context as well as in the multi-option context. Accounting for the spatial requirements of multiple species and allowing for several conservation options is however complicated, due to trade-offs in species requirements. It is also shown that spatial SHDMs can be successfully used for gaining information on factors that drive a species spatial distribution. Such information is valuable to conservation planning, as better knowledge on species requirements facilitates the design of networks for species persistence. This methods and results described in this thesis aim to improve species probabilities of persistence, by taking better account of species habitat and spatial requirements. Many real-world conservation planning problems are characterised by a variety of conservation options related to protection, restoration and maintenance of habitat. Planning tools therefore need to be able to incorporate multiple conservation options per site, in order to continue the search for cost-effective conservation planning solutions. Simultaneously, the spatial requirements of species need to be considered. The methods described in this thesis offer a starting point for combining these two relevant aspects of conservation planning.

Carrie the Musical

When Carrie the Musical first debuted in 1988 it (in)famously closed eight days later, earning the dubious title of being one of the biggest flops in the history of Broadway. This revived version of the work, the Queensland premiere of the production, presented at the Brisbane Powerhouse in January 2016, was a calculated experiment in the commercialisation of an historical flop into a contemporary success. Through collaboration between some of Brisbane's most promising young creatives, designers, choreographers musicians and performers, this production became one of the Brisbane Powerhouse's most successful shows and gained local, national and international recognition for its achievements. By pushing the boundaries of the most current trends in contemporary Australian directing and performance making, the creative team was able to draw on their innovative capacity as independent theatre makers to turn a once-maligned work into a modern-day financial and critical success.

Probiotics modify tight junction proteins in an animal model of non-alcoholic fatty liver disease

Objectives We have investigated the effects of a multi–species probiotic preparation containing a combination of probiotic bacterial genera that included Bifidobacteria, Lactobacilli and a Streptococcus in a mouse model of high fat diet/obesity induced liver steatosis. Methods Three groups of C57B1/6J mice were fed either a standard chow or a high fat diet for 20 weeks, while a third group was fed a high fat diet for 10 weeks and then concomitantly administered probiotics for a further 10 weeks. Serum, liver and large bowel samples were collected for analysis. Results The expression of the tight junction proteins ZO-1 and ZO-2 was reduced (p < 0.05) in high fat diet fed mice compared to chow fed mice. Probiotic supplementation helped to maintain tight ZO-1 and ZO-2 expression compared with the high fat diet group (p < 0.05), but did not restore ZO-1 or ZO-2 expression compared with chow fed mice. Mice fed a high fat diet ± probiotics had significant steatosis development compared to chow fed mice (p < 0.05); steatosis was less severe in the probiotics group compared to the high fat diet group. Hepatic triglycerides concentration was higher in mice fed a high fat diet ± probiotics compared to the chow group (p < 0.05), and was lower in the probiotics group compared to the high fat diet group (p < 0.05). Compared to chow fed mice, serum glucose and cholesterol concentrations, and the activity of alanine transaminase were higher (p < 0.05), whereas serum triglyceride concentration was lower (p < 0.05) in mice fed a high fat diet ± probiotics. Conclusions Supplementation with a multi-species probiotic formulation helped to maintain tight junction proteins ZO-1 and ZO-2, and reduced hepatic triglyceride concentrations compared with a HFD alone.

Syntheses and structural studies of new bicyclic 1,3-diphenyl-1,3,2.lambda.3,4.lambda.3-diazadiphosphetidines

Reactions of cis-[(C6H5N)PC1]z(1 ) with the difunctional reagents HO(CH2)20H,H (CH3)N(CHz)zN(CH3)HH, (CH3)N(CH& OH, and HO(CHz)30Hi n the presence of triethylamine yield the new bicyclic 1,3,2X3,4h3-diazadiphosphetidines[( C6H5- N)PIZ[-O(CHZ)Zo-l (2), [(C6H5N)PlZ[-(CH3)N(CHZ)ZN(CH3)-l (319 [(C6H~N)PlZ~-(CH3)N(cHZ)20 (4), and [(C6H5 N)P],[-Q(CH2),0-] (5), respectively. The products have been characterized by elemental analyses and IR and NMR spectroscopic data. The structures of 4 and 5 have been determined by single-crystal X-ray analysis. Crystal data for 4: monoclinic, P2,/c, a = 9.823 (2) A, b = 8.608 (1) A, c = 18.423 (3) A, i3 = 90.55 (1)O, Z = 4. Crystal data for 5 monoclinic, P2,/c, a = 9.727 (2) A, b = 8.064 (2) A, c = 19.702 (4) A, @ =I 91.31 (l)', 2 = 4. The structures have been solved by direct methods and refined to R = 0.028 for 4 and R = 0.050 for 5. Compound 4 is the first example of an aminoalkoxy-l,3,2X3,4X3-diazadiphosphetidine. The PzNz ring is slightly puckered in both 4 and 5 and the puckering occurs in a manner opposite to that observed for cis-[(RN)PX],structures.

径向收缩的等离子体的运动不稳定性

<正> 近几年来,人们详细地研究过等离子体某些运动状态的不稳定性,如Rayleigh-Taylor不稳定性和Kelvin-Helmholtz不稳定性等等。本文先根据雪铲模型讨论收缩效应的运动不稳定性,其次指出,在径向运动情形下,稳定性不只和加速度有关,而且也和速度等其它因素有关,因此,它并不相当于平面情形的Rayleig-Taylor不稳定性。 1.收缩效应的运动不稳定性在雪铲模型里,如果假定在某时刻t_1出现径向、周向和轴向的微扰动γ,θ,z,并以初始时刻to的位置θo、Zo以及时刻t为自变量,则在假定(γ,θ,z)的形式为(γ(t),-iθ(t),-iz(t))eimθo+ikzσ之后,就可得到线性化的扰动方程(采用高斯单位)为:

Corrosion inhibition of carbon steel in tetra-n-butylammonium bromide aqueous solution by benzotriazole and Na3PO4

The corrosion inhibition behavior of benzotriazole, Na3PO4 and their mixture on carbon steel in 20 wt.% (0.628 mol l(-1)) tetra-n-butylammonium bromide aerated aqueous solution was investigated by weight-loss test, potentiodynamic polarization measurement, electrochemical impedance spectroscopy and scanning electron microscope/energy dispersive X-ray techniques. The inhibition action of BTA or SP or inhibitors mixture on the corrosion of carbon steel is mainly due to the inhibition of anodic process of corrosion. The results revealed that inhibitors mixtures have shown synergistic effects at lower concentration of inhibitors. At 2 g l(-1) BTA and 2 g l(-1) SP showed optimum enhanced inhibition compared with their individual effects.

金属溶剂萃取的数学模拟研究

溶剂萃取三出口分离工艺是在分馏萃取流程基础上提出的一种新工艺方法，应用这种流程，每个工艺可根据各组分萃取能力的不同得到三个不同的产品，因此具有很大的优越性。本工作首先进行了皂化P507对Cu、Co、Ni三种金属元素萃取分离性能的研究，得到了工艺设计的一些主要参数及其变化规律。在此基础上，设计了两种方式的三出口工艺，应用P507－煤油体系，对组成为1:1:1的Cu、Co、Ni混合合成料液进行同时分离串级实验，实现了三种元素的同时分离，从而将三出口工艺推广应用于非稀土体系，并对两种不同的三出口流程设计方式进行了比较，得出了有意义的结果。对串级过程的数学模拟引入了稀疏矩阵方法，并对分馏萃取体系工艺参数的优化作了尝试。通过对串给模拟计算中矩阵解法的分析，发现计算过程中的所用的大型微分矩阵是一种零元占绝对优势的稀疏矩阵。本工作根据此微分矩阵的特点，采用稀疏矩阵所特有的存贮方法，将解大型稀疏线性方程组的方法引入串级模拟计算，编制了计算程序，使矩阵法的内存占用量大大减小，而计算速度却基本上没有变化，为矩阵方法应用于高级数及多组分体系的串级模拟计算提供了基础。我们还对分馏萃取工艺参数的优化作了尝试，分别应用复合形法和直接网格搜索法编制计算程序，在料液组成一定、进料量一定的条件下，建立了目标函数：Q = N*(VOE * Zo)/(VAE * XX(1,1)对(Sm-Gd)(No_3)_3-HNo_3-P507－煤油体系，分别以级数。进料级等六个或四个变量为搜索变量。应用上述以稀疏矩阵法改进后的串级模拟程序计算目标函数，进行优化计算，得到了合理的结果。两种优化方法比较后，认为复形方法所耗机时少，较为实用。为了对Cu、Co、Ni的萃取分离体系进行数学模拟，进行了单级分配实验，通过对实验结果的分析，利用线性回归方法。得到了适用于不同浓度范围的简单的单级分配模型。研究了三出口工艺中的平衡关系，提出了两种分别适用于不同方式三出口工艺串级计算的串级模型，并在分馏萃取的基础上将稀疏矩阵方法引入三出口串级计算，对工艺一，根据流程特点，假定串级过程中分离 数变化不大；对工艺二，利用所建立的单级分配模型，分别用FORTRAN语言编制程序，串级计算的结果与实验结果基本吻合。将溶液理论应用于萃取过程的计算是目前人们努力的一个方面。本工作对于P507－正庚烷萃取CuSo_4体系进行了溶液理论模型的研究，对于水相，应用适用范围广，计算精度高的Pitger理论计算平均离子活度，并将其部分为单离子活度系数，对有机相，应用Scatacherrd-Hilbrand的“溶度参数“理论模型进行关联，得到了模型的端值常数和热力学萃取常数。

数学模拟法优化设计氨化体系稀土分离工艺

应用数学模拟法对氨化环烷酸体系分离钇与镧系元素的萃到过程及氨化P_(507)体系分离稀土元素的萃取过程分别进行了优化工艺设计。采用复合形优化法，在进料浓度和进料量一定的情况下，选取 Q = (N · Zo · VOE)/(x(1, 1)·VAE)为目标函数。选取N、NF、Zo、VOE、Hw和VAW为六个优化参数，选取二出口产品的纯度和收率为约束条件。首先对氨化环烷酸体系分离Y与镧系元素（Nd）的串级萃取过程进行了优化工艺设计。优化设计中所用的串级计算采用了占计算机内存较小的求解稀疏矩阵的方法。在满足出口产品Y的纯度不小于99.98%的情况下，得到了一组优化工艺参数和该优化工艺条件下的各级二相数据。并与已有实验结果进行了对比，论证了其合理性。其次，将逐级计算法引入了优化设计过程，对氨化环烷酸体系分离Y与Nd的过程再次进行了计算，并与矩阵法结果作了对比，认为逐级计算法可以与优化方法结合设计工艺。用此方法对氨化环烷酸体系分离Y与Nd，Er的串级萃取过程进行了优化工艺设计，在满足出口产品Y纯度≥99.99%的情况下，得到了一组优化工艺参数，同时给出了优化工艺条件下的各级二相数据，对比已有实验，结果比较满意。利用所提出的方法对文献报道的从江西矿分离高纯Y的实际过程进行了计算，所得的结果与串级理论设计出的结果比较接近。由于文献已进行了实验验证，故可以认为本文所得的结果基本可靠。最后，在分析了氨化P_(507)体系萃取稀土元素的特点以后，提出了逐级计算法与复合优化法相结合来优化工艺参数。在水相出口级、进料级、有机相出口级建立单级分配模型，采用所建立的模型和方法对氨化P_(507)体系分离Nd, Sm的串级萃取过程进行了优化工艺设计，得到了一组优化参数及优化工艺下的二相各级各组分浓度，并在优化的工艺条件下做了验证实验，实验结果与计算结果基本吻合。

Creation of a complex butterfly attractor using a novel Lorenz-type system

A novel Lorenz-type system of nonlinear differential equations is proposed. Unlike the original Lorenz system, where the chaotic dynamics remain confined to the positive half-space with respect to the Z state variable due to a limiting threshold effect, the proposed system enables bipolar swing of this state variable. In addition, the classical set of parameters (a, b, c) controlling the behavior of the Lorenz system are reduced to a single parameter, namely a. Two possible modes of operation are admitted by the system; switching between these two modes results in the creation of a complex butterfly chaotic attractor. Numerical simulations and results from an experimental setup are presented

Electronic Techtonics: Thinking at the Interface

This volume originated in HASTAC’s first international conference, “Electronic Techtonics: Thinking at the Interface,” held at Duke University during April 19-21, 2007. “Electronic Techtonics” was the site of truly unforgettable conversations and encounters that traversed domains, disciplines, and media – conversations that explored the fluidity of technology both as interface as well as at the interface. This hardcopy version of the conference proceedings is published in conjunction with its electronic counterpart (found at www.hastac.org). Both versions exist as records of the range and depth of conversations that took place at the conference. Some of the papers in this volume are almost exact records of talks given at the conference, while others are versions that were revised and reworked some time after the conference. These papers are drawn from a variety of fields and we have not made an effort to homogenize them in any way, but have instead retained the individual format and style of each author.

Solution structure of the N-terminal transactivation domain of ERM modified by SUMO-1.

ERM is a member of the PEA3 group of the Ets transcription factor family that plays important roles in development and tumorigenesis. The PEA3s share an N-terminal transactivation domain (TADn) whose activity is inhibited by small ubiquitin-like modifier (SUMO). However, the consequences of sumoylation and its underlying molecular mechanism remain unclear. The domain structure of ERM TADn alone or modified by SUMO-1 was analyzed using small-angle X-ray scattering (SAXS). Low resolution shapes determined ab initio from the scattering data indicated an elongated shape and an unstructured conformation of TADn in solution. Covalent attachment of SUMO-1 does not perturb the structure of TADn as indicated by the linear arrangement of the SUMO moiety with respect to TADn. Thus, ERM belongs to the growing family of proteins that contain intrinsically unstructured regions. The flexible nature of TADn may be instrumental for ERM recognition and binding to diverse molecular partners.